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v5.4
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * PCI Bus Services, see include/linux/pci.h for further explanation.
   4 *
   5 * Copyright 1993 -- 1997 Drew Eckhardt, Frederic Potter,
   6 * David Mosberger-Tang
   7 *
   8 * Copyright 1997 -- 2000 Martin Mares <mj@ucw.cz>
   9 */
  10
  11#include <linux/acpi.h>
  12#include <linux/kernel.h>
  13#include <linux/delay.h>
  14#include <linux/dmi.h>
  15#include <linux/init.h>
  16#include <linux/of.h>
  17#include <linux/of_pci.h>
  18#include <linux/pci.h>
  19#include <linux/pm.h>
  20#include <linux/slab.h>
  21#include <linux/module.h>
  22#include <linux/spinlock.h>
  23#include <linux/string.h>
  24#include <linux/log2.h>
  25#include <linux/logic_pio.h>
  26#include <linux/pm_wakeup.h>
  27#include <linux/interrupt.h>
  28#include <linux/device.h>
  29#include <linux/pm_runtime.h>
  30#include <linux/pci_hotplug.h>
  31#include <linux/vmalloc.h>
  32#include <linux/pci-ats.h>
  33#include <asm/setup.h>
  34#include <asm/dma.h>
  35#include <linux/aer.h>
  36#include "pci.h"
  37
  38DEFINE_MUTEX(pci_slot_mutex);
  39
  40const char *pci_power_names[] = {
  41	"error", "D0", "D1", "D2", "D3hot", "D3cold", "unknown",
  42};
  43EXPORT_SYMBOL_GPL(pci_power_names);
  44
  45int isa_dma_bridge_buggy;
  46EXPORT_SYMBOL(isa_dma_bridge_buggy);
  47
  48int pci_pci_problems;
  49EXPORT_SYMBOL(pci_pci_problems);
  50
  51unsigned int pci_pm_d3_delay;
  52
  53static void pci_pme_list_scan(struct work_struct *work);
  54
  55static LIST_HEAD(pci_pme_list);
  56static DEFINE_MUTEX(pci_pme_list_mutex);
  57static DECLARE_DELAYED_WORK(pci_pme_work, pci_pme_list_scan);
  58
  59struct pci_pme_device {
  60	struct list_head list;
  61	struct pci_dev *dev;
  62};
  63
  64#define PME_TIMEOUT 1000 /* How long between PME checks */
  65
  66static void pci_dev_d3_sleep(struct pci_dev *dev)
  67{
  68	unsigned int delay = dev->d3_delay;
  69
  70	if (delay < pci_pm_d3_delay)
  71		delay = pci_pm_d3_delay;
  72
  73	if (delay)
  74		msleep(delay);
  75}
  76
  77#ifdef CONFIG_PCI_DOMAINS
  78int pci_domains_supported = 1;
  79#endif
  80
  81#define DEFAULT_CARDBUS_IO_SIZE		(256)
  82#define DEFAULT_CARDBUS_MEM_SIZE	(64*1024*1024)
  83/* pci=cbmemsize=nnM,cbiosize=nn can override this */
  84unsigned long pci_cardbus_io_size = DEFAULT_CARDBUS_IO_SIZE;
  85unsigned long pci_cardbus_mem_size = DEFAULT_CARDBUS_MEM_SIZE;
  86
  87#define DEFAULT_HOTPLUG_IO_SIZE		(256)
  88#define DEFAULT_HOTPLUG_MEM_SIZE	(2*1024*1024)
  89/* pci=hpmemsize=nnM,hpiosize=nn can override this */
  90unsigned long pci_hotplug_io_size  = DEFAULT_HOTPLUG_IO_SIZE;
  91unsigned long pci_hotplug_mem_size = DEFAULT_HOTPLUG_MEM_SIZE;
  92
  93#define DEFAULT_HOTPLUG_BUS_SIZE	1
  94unsigned long pci_hotplug_bus_size = DEFAULT_HOTPLUG_BUS_SIZE;
  95
  96enum pcie_bus_config_types pcie_bus_config = PCIE_BUS_DEFAULT;
  97
  98/*
  99 * The default CLS is used if arch didn't set CLS explicitly and not
 100 * all pci devices agree on the same value.  Arch can override either
 101 * the dfl or actual value as it sees fit.  Don't forget this is
 102 * measured in 32-bit words, not bytes.
 103 */
 104u8 pci_dfl_cache_line_size = L1_CACHE_BYTES >> 2;
 105u8 pci_cache_line_size;
 106
 107/*
 108 * If we set up a device for bus mastering, we need to check the latency
 109 * timer as certain BIOSes forget to set it properly.
 110 */
 111unsigned int pcibios_max_latency = 255;
 112
 113/* If set, the PCIe ARI capability will not be used. */
 114static bool pcie_ari_disabled;
 115
 116/* If set, the PCIe ATS capability will not be used. */
 117static bool pcie_ats_disabled;
 118
 119/* If set, the PCI config space of each device is printed during boot. */
 120bool pci_early_dump;
 121
 122bool pci_ats_disabled(void)
 123{
 124	return pcie_ats_disabled;
 125}
 126
 127/* Disable bridge_d3 for all PCIe ports */
 128static bool pci_bridge_d3_disable;
 129/* Force bridge_d3 for all PCIe ports */
 130static bool pci_bridge_d3_force;
 131
 132static int __init pcie_port_pm_setup(char *str)
 133{
 134	if (!strcmp(str, "off"))
 135		pci_bridge_d3_disable = true;
 136	else if (!strcmp(str, "force"))
 137		pci_bridge_d3_force = true;
 138	return 1;
 139}
 140__setup("pcie_port_pm=", pcie_port_pm_setup);
 141
 142/* Time to wait after a reset for device to become responsive */
 143#define PCIE_RESET_READY_POLL_MS 60000
 144
 145/**
 146 * pci_bus_max_busnr - returns maximum PCI bus number of given bus' children
 147 * @bus: pointer to PCI bus structure to search
 148 *
 149 * Given a PCI bus, returns the highest PCI bus number present in the set
 150 * including the given PCI bus and its list of child PCI buses.
 151 */
 152unsigned char pci_bus_max_busnr(struct pci_bus *bus)
 153{
 154	struct pci_bus *tmp;
 155	unsigned char max, n;
 156
 157	max = bus->busn_res.end;
 158	list_for_each_entry(tmp, &bus->children, node) {
 159		n = pci_bus_max_busnr(tmp);
 160		if (n > max)
 161			max = n;
 162	}
 163	return max;
 164}
 165EXPORT_SYMBOL_GPL(pci_bus_max_busnr);
 166
 167#ifdef CONFIG_HAS_IOMEM
 168void __iomem *pci_ioremap_bar(struct pci_dev *pdev, int bar)
 169{
 170	struct resource *res = &pdev->resource[bar];
 171
 172	/*
 173	 * Make sure the BAR is actually a memory resource, not an IO resource
 174	 */
 175	if (res->flags & IORESOURCE_UNSET || !(res->flags & IORESOURCE_MEM)) {
 176		pci_warn(pdev, "can't ioremap BAR %d: %pR\n", bar, res);
 177		return NULL;
 178	}
 179	return ioremap_nocache(res->start, resource_size(res));
 180}
 181EXPORT_SYMBOL_GPL(pci_ioremap_bar);
 182
 183void __iomem *pci_ioremap_wc_bar(struct pci_dev *pdev, int bar)
 184{
 185	/*
 186	 * Make sure the BAR is actually a memory resource, not an IO resource
 187	 */
 188	if (!(pci_resource_flags(pdev, bar) & IORESOURCE_MEM)) {
 189		WARN_ON(1);
 190		return NULL;
 191	}
 192	return ioremap_wc(pci_resource_start(pdev, bar),
 193			  pci_resource_len(pdev, bar));
 194}
 195EXPORT_SYMBOL_GPL(pci_ioremap_wc_bar);
 196#endif
 197
 198/**
 199 * pci_dev_str_match_path - test if a path string matches a device
 200 * @dev: the PCI device to test
 201 * @path: string to match the device against
 202 * @endptr: pointer to the string after the match
 203 *
 204 * Test if a string (typically from a kernel parameter) formatted as a
 205 * path of device/function addresses matches a PCI device. The string must
 206 * be of the form:
 207 *
 208 *   [<domain>:]<bus>:<device>.<func>[/<device>.<func>]*
 209 *
 210 * A path for a device can be obtained using 'lspci -t'.  Using a path
 211 * is more robust against bus renumbering than using only a single bus,
 212 * device and function address.
 213 *
 214 * Returns 1 if the string matches the device, 0 if it does not and
 215 * a negative error code if it fails to parse the string.
 216 */
 217static int pci_dev_str_match_path(struct pci_dev *dev, const char *path,
 218				  const char **endptr)
 219{
 220	int ret;
 221	int seg, bus, slot, func;
 222	char *wpath, *p;
 223	char end;
 224
 225	*endptr = strchrnul(path, ';');
 226
 227	wpath = kmemdup_nul(path, *endptr - path, GFP_KERNEL);
 228	if (!wpath)
 229		return -ENOMEM;
 230
 231	while (1) {
 232		p = strrchr(wpath, '/');
 233		if (!p)
 234			break;
 235		ret = sscanf(p, "/%x.%x%c", &slot, &func, &end);
 236		if (ret != 2) {
 237			ret = -EINVAL;
 238			goto free_and_exit;
 239		}
 240
 241		if (dev->devfn != PCI_DEVFN(slot, func)) {
 242			ret = 0;
 243			goto free_and_exit;
 244		}
 245
 246		/*
 247		 * Note: we don't need to get a reference to the upstream
 248		 * bridge because we hold a reference to the top level
 249		 * device which should hold a reference to the bridge,
 250		 * and so on.
 251		 */
 252		dev = pci_upstream_bridge(dev);
 253		if (!dev) {
 254			ret = 0;
 255			goto free_and_exit;
 256		}
 257
 258		*p = 0;
 259	}
 260
 261	ret = sscanf(wpath, "%x:%x:%x.%x%c", &seg, &bus, &slot,
 262		     &func, &end);
 263	if (ret != 4) {
 264		seg = 0;
 265		ret = sscanf(wpath, "%x:%x.%x%c", &bus, &slot, &func, &end);
 266		if (ret != 3) {
 267			ret = -EINVAL;
 268			goto free_and_exit;
 269		}
 270	}
 271
 272	ret = (seg == pci_domain_nr(dev->bus) &&
 273	       bus == dev->bus->number &&
 274	       dev->devfn == PCI_DEVFN(slot, func));
 275
 276free_and_exit:
 277	kfree(wpath);
 278	return ret;
 279}
 280
 281/**
 282 * pci_dev_str_match - test if a string matches a device
 283 * @dev: the PCI device to test
 284 * @p: string to match the device against
 285 * @endptr: pointer to the string after the match
 286 *
 287 * Test if a string (typically from a kernel parameter) matches a specified
 288 * PCI device. The string may be of one of the following formats:
 289 *
 290 *   [<domain>:]<bus>:<device>.<func>[/<device>.<func>]*
 291 *   pci:<vendor>:<device>[:<subvendor>:<subdevice>]
 292 *
 293 * The first format specifies a PCI bus/device/function address which
 294 * may change if new hardware is inserted, if motherboard firmware changes,
 295 * or due to changes caused in kernel parameters. If the domain is
 296 * left unspecified, it is taken to be 0.  In order to be robust against
 297 * bus renumbering issues, a path of PCI device/function numbers may be used
 298 * to address the specific device.  The path for a device can be determined
 299 * through the use of 'lspci -t'.
 300 *
 301 * The second format matches devices using IDs in the configuration
 302 * space which may match multiple devices in the system. A value of 0
 303 * for any field will match all devices. (Note: this differs from
 304 * in-kernel code that uses PCI_ANY_ID which is ~0; this is for
 305 * legacy reasons and convenience so users don't have to specify
 306 * FFFFFFFFs on the command line.)
 307 *
 308 * Returns 1 if the string matches the device, 0 if it does not and
 309 * a negative error code if the string cannot be parsed.
 310 */
 311static int pci_dev_str_match(struct pci_dev *dev, const char *p,
 312			     const char **endptr)
 313{
 314	int ret;
 315	int count;
 316	unsigned short vendor, device, subsystem_vendor, subsystem_device;
 317
 318	if (strncmp(p, "pci:", 4) == 0) {
 319		/* PCI vendor/device (subvendor/subdevice) IDs are specified */
 320		p += 4;
 321		ret = sscanf(p, "%hx:%hx:%hx:%hx%n", &vendor, &device,
 322			     &subsystem_vendor, &subsystem_device, &count);
 323		if (ret != 4) {
 324			ret = sscanf(p, "%hx:%hx%n", &vendor, &device, &count);
 325			if (ret != 2)
 326				return -EINVAL;
 327
 328			subsystem_vendor = 0;
 329			subsystem_device = 0;
 330		}
 331
 332		p += count;
 333
 334		if ((!vendor || vendor == dev->vendor) &&
 335		    (!device || device == dev->device) &&
 336		    (!subsystem_vendor ||
 337			    subsystem_vendor == dev->subsystem_vendor) &&
 338		    (!subsystem_device ||
 339			    subsystem_device == dev->subsystem_device))
 340			goto found;
 341	} else {
 342		/*
 343		 * PCI Bus, Device, Function IDs are specified
 344		 * (optionally, may include a path of devfns following it)
 345		 */
 346		ret = pci_dev_str_match_path(dev, p, &p);
 347		if (ret < 0)
 348			return ret;
 349		else if (ret)
 350			goto found;
 351	}
 352
 353	*endptr = p;
 354	return 0;
 355
 356found:
 357	*endptr = p;
 358	return 1;
 359}
 360
 361static int __pci_find_next_cap_ttl(struct pci_bus *bus, unsigned int devfn,
 362				   u8 pos, int cap, int *ttl)
 363{
 364	u8 id;
 365	u16 ent;
 366
 367	pci_bus_read_config_byte(bus, devfn, pos, &pos);
 368
 369	while ((*ttl)--) {
 
 370		if (pos < 0x40)
 371			break;
 372		pos &= ~3;
 373		pci_bus_read_config_word(bus, devfn, pos, &ent);
 374
 375		id = ent & 0xff;
 376		if (id == 0xff)
 377			break;
 378		if (id == cap)
 379			return pos;
 380		pos = (ent >> 8);
 381	}
 382	return 0;
 383}
 384
 385static int __pci_find_next_cap(struct pci_bus *bus, unsigned int devfn,
 386			       u8 pos, int cap)
 387{
 388	int ttl = PCI_FIND_CAP_TTL;
 389
 390	return __pci_find_next_cap_ttl(bus, devfn, pos, cap, &ttl);
 391}
 392
 393int pci_find_next_capability(struct pci_dev *dev, u8 pos, int cap)
 394{
 395	return __pci_find_next_cap(dev->bus, dev->devfn,
 396				   pos + PCI_CAP_LIST_NEXT, cap);
 397}
 398EXPORT_SYMBOL_GPL(pci_find_next_capability);
 399
 400static int __pci_bus_find_cap_start(struct pci_bus *bus,
 401				    unsigned int devfn, u8 hdr_type)
 402{
 403	u16 status;
 404
 405	pci_bus_read_config_word(bus, devfn, PCI_STATUS, &status);
 406	if (!(status & PCI_STATUS_CAP_LIST))
 407		return 0;
 408
 409	switch (hdr_type) {
 410	case PCI_HEADER_TYPE_NORMAL:
 411	case PCI_HEADER_TYPE_BRIDGE:
 412		return PCI_CAPABILITY_LIST;
 413	case PCI_HEADER_TYPE_CARDBUS:
 414		return PCI_CB_CAPABILITY_LIST;
 
 
 415	}
 416
 417	return 0;
 418}
 419
 420/**
 421 * pci_find_capability - query for devices' capabilities
 422 * @dev: PCI device to query
 423 * @cap: capability code
 424 *
 425 * Tell if a device supports a given PCI capability.
 426 * Returns the address of the requested capability structure within the
 427 * device's PCI configuration space or 0 in case the device does not
 428 * support it.  Possible values for @cap include:
 429 *
 430 *  %PCI_CAP_ID_PM           Power Management
 431 *  %PCI_CAP_ID_AGP          Accelerated Graphics Port
 432 *  %PCI_CAP_ID_VPD          Vital Product Data
 433 *  %PCI_CAP_ID_SLOTID       Slot Identification
 434 *  %PCI_CAP_ID_MSI          Message Signalled Interrupts
 435 *  %PCI_CAP_ID_CHSWP        CompactPCI HotSwap
 436 *  %PCI_CAP_ID_PCIX         PCI-X
 437 *  %PCI_CAP_ID_EXP          PCI Express
 438 */
 439int pci_find_capability(struct pci_dev *dev, int cap)
 440{
 441	int pos;
 442
 443	pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
 444	if (pos)
 445		pos = __pci_find_next_cap(dev->bus, dev->devfn, pos, cap);
 446
 447	return pos;
 448}
 449EXPORT_SYMBOL(pci_find_capability);
 450
 451/**
 452 * pci_bus_find_capability - query for devices' capabilities
 453 * @bus: the PCI bus to query
 454 * @devfn: PCI device to query
 455 * @cap: capability code
 456 *
 457 * Like pci_find_capability() but works for PCI devices that do not have a
 458 * pci_dev structure set up yet.
 459 *
 460 * Returns the address of the requested capability structure within the
 461 * device's PCI configuration space or 0 in case the device does not
 462 * support it.
 463 */
 464int pci_bus_find_capability(struct pci_bus *bus, unsigned int devfn, int cap)
 465{
 466	int pos;
 467	u8 hdr_type;
 468
 469	pci_bus_read_config_byte(bus, devfn, PCI_HEADER_TYPE, &hdr_type);
 470
 471	pos = __pci_bus_find_cap_start(bus, devfn, hdr_type & 0x7f);
 472	if (pos)
 473		pos = __pci_find_next_cap(bus, devfn, pos, cap);
 474
 475	return pos;
 476}
 477EXPORT_SYMBOL(pci_bus_find_capability);
 478
 479/**
 480 * pci_find_next_ext_capability - Find an extended capability
 481 * @dev: PCI device to query
 482 * @start: address at which to start looking (0 to start at beginning of list)
 483 * @cap: capability code
 484 *
 485 * Returns the address of the next matching extended capability structure
 486 * within the device's PCI configuration space or 0 if the device does
 487 * not support it.  Some capabilities can occur several times, e.g., the
 488 * vendor-specific capability, and this provides a way to find them all.
 489 */
 490int pci_find_next_ext_capability(struct pci_dev *dev, int start, int cap)
 491{
 492	u32 header;
 493	int ttl;
 494	int pos = PCI_CFG_SPACE_SIZE;
 495
 496	/* minimum 8 bytes per capability */
 497	ttl = (PCI_CFG_SPACE_EXP_SIZE - PCI_CFG_SPACE_SIZE) / 8;
 498
 499	if (dev->cfg_size <= PCI_CFG_SPACE_SIZE)
 500		return 0;
 501
 502	if (start)
 503		pos = start;
 504
 505	if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
 506		return 0;
 507
 508	/*
 509	 * If we have no capabilities, this is indicated by cap ID,
 510	 * cap version and next pointer all being 0.
 511	 */
 512	if (header == 0)
 513		return 0;
 514
 515	while (ttl-- > 0) {
 516		if (PCI_EXT_CAP_ID(header) == cap && pos != start)
 517			return pos;
 518
 519		pos = PCI_EXT_CAP_NEXT(header);
 520		if (pos < PCI_CFG_SPACE_SIZE)
 521			break;
 522
 523		if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
 524			break;
 525	}
 526
 527	return 0;
 528}
 529EXPORT_SYMBOL_GPL(pci_find_next_ext_capability);
 530
 531/**
 532 * pci_find_ext_capability - Find an extended capability
 533 * @dev: PCI device to query
 534 * @cap: capability code
 535 *
 536 * Returns the address of the requested extended capability structure
 537 * within the device's PCI configuration space or 0 if the device does
 538 * not support it.  Possible values for @cap include:
 539 *
 540 *  %PCI_EXT_CAP_ID_ERR		Advanced Error Reporting
 541 *  %PCI_EXT_CAP_ID_VC		Virtual Channel
 542 *  %PCI_EXT_CAP_ID_DSN		Device Serial Number
 543 *  %PCI_EXT_CAP_ID_PWR		Power Budgeting
 544 */
 545int pci_find_ext_capability(struct pci_dev *dev, int cap)
 546{
 547	return pci_find_next_ext_capability(dev, 0, cap);
 548}
 549EXPORT_SYMBOL_GPL(pci_find_ext_capability);
 550
 551static int __pci_find_next_ht_cap(struct pci_dev *dev, int pos, int ht_cap)
 552{
 553	int rc, ttl = PCI_FIND_CAP_TTL;
 554	u8 cap, mask;
 555
 556	if (ht_cap == HT_CAPTYPE_SLAVE || ht_cap == HT_CAPTYPE_HOST)
 557		mask = HT_3BIT_CAP_MASK;
 558	else
 559		mask = HT_5BIT_CAP_MASK;
 560
 561	pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn, pos,
 562				      PCI_CAP_ID_HT, &ttl);
 563	while (pos) {
 564		rc = pci_read_config_byte(dev, pos + 3, &cap);
 565		if (rc != PCIBIOS_SUCCESSFUL)
 566			return 0;
 567
 568		if ((cap & mask) == ht_cap)
 569			return pos;
 570
 571		pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn,
 572					      pos + PCI_CAP_LIST_NEXT,
 573					      PCI_CAP_ID_HT, &ttl);
 574	}
 575
 576	return 0;
 577}
 578/**
 579 * pci_find_next_ht_capability - query a device's Hypertransport capabilities
 580 * @dev: PCI device to query
 581 * @pos: Position from which to continue searching
 582 * @ht_cap: Hypertransport capability code
 583 *
 584 * To be used in conjunction with pci_find_ht_capability() to search for
 585 * all capabilities matching @ht_cap. @pos should always be a value returned
 586 * from pci_find_ht_capability().
 587 *
 588 * NB. To be 100% safe against broken PCI devices, the caller should take
 589 * steps to avoid an infinite loop.
 590 */
 591int pci_find_next_ht_capability(struct pci_dev *dev, int pos, int ht_cap)
 592{
 593	return __pci_find_next_ht_cap(dev, pos + PCI_CAP_LIST_NEXT, ht_cap);
 594}
 595EXPORT_SYMBOL_GPL(pci_find_next_ht_capability);
 596
 597/**
 598 * pci_find_ht_capability - query a device's Hypertransport capabilities
 599 * @dev: PCI device to query
 600 * @ht_cap: Hypertransport capability code
 601 *
 602 * Tell if a device supports a given Hypertransport capability.
 603 * Returns an address within the device's PCI configuration space
 604 * or 0 in case the device does not support the request capability.
 605 * The address points to the PCI capability, of type PCI_CAP_ID_HT,
 606 * which has a Hypertransport capability matching @ht_cap.
 607 */
 608int pci_find_ht_capability(struct pci_dev *dev, int ht_cap)
 609{
 610	int pos;
 611
 612	pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
 613	if (pos)
 614		pos = __pci_find_next_ht_cap(dev, pos, ht_cap);
 615
 616	return pos;
 617}
 618EXPORT_SYMBOL_GPL(pci_find_ht_capability);
 619
 620/**
 621 * pci_find_parent_resource - return resource region of parent bus of given
 622 *			      region
 623 * @dev: PCI device structure contains resources to be searched
 624 * @res: child resource record for which parent is sought
 625 *
 626 * For given resource region of given device, return the resource region of
 627 * parent bus the given region is contained in.
 628 */
 629struct resource *pci_find_parent_resource(const struct pci_dev *dev,
 630					  struct resource *res)
 631{
 632	const struct pci_bus *bus = dev->bus;
 633	struct resource *r;
 634	int i;
 635
 636	pci_bus_for_each_resource(bus, r, i) {
 637		if (!r)
 638			continue;
 639		if (resource_contains(r, res)) {
 640
 641			/*
 642			 * If the window is prefetchable but the BAR is
 643			 * not, the allocator made a mistake.
 644			 */
 645			if (r->flags & IORESOURCE_PREFETCH &&
 646			    !(res->flags & IORESOURCE_PREFETCH))
 647				return NULL;
 648
 649			/*
 650			 * If we're below a transparent bridge, there may
 651			 * be both a positively-decoded aperture and a
 652			 * subtractively-decoded region that contain the BAR.
 653			 * We want the positively-decoded one, so this depends
 654			 * on pci_bus_for_each_resource() giving us those
 655			 * first.
 656			 */
 657			return r;
 658		}
 659	}
 660	return NULL;
 661}
 662EXPORT_SYMBOL(pci_find_parent_resource);
 663
 664/**
 665 * pci_find_resource - Return matching PCI device resource
 666 * @dev: PCI device to query
 667 * @res: Resource to look for
 668 *
 669 * Goes over standard PCI resources (BARs) and checks if the given resource
 670 * is partially or fully contained in any of them. In that case the
 671 * matching resource is returned, %NULL otherwise.
 672 */
 673struct resource *pci_find_resource(struct pci_dev *dev, struct resource *res)
 674{
 675	int i;
 676
 677	for (i = 0; i < PCI_ROM_RESOURCE; i++) {
 678		struct resource *r = &dev->resource[i];
 679
 680		if (r->start && resource_contains(r, res))
 681			return r;
 682	}
 683
 684	return NULL;
 685}
 686EXPORT_SYMBOL(pci_find_resource);
 687
 688/**
 689 * pci_find_pcie_root_port - return PCIe Root Port
 690 * @dev: PCI device to query
 691 *
 692 * Traverse up the parent chain and return the PCIe Root Port PCI Device
 693 * for a given PCI Device.
 694 */
 695struct pci_dev *pci_find_pcie_root_port(struct pci_dev *dev)
 696{
 697	struct pci_dev *bridge, *highest_pcie_bridge = dev;
 698
 699	bridge = pci_upstream_bridge(dev);
 700	while (bridge && pci_is_pcie(bridge)) {
 701		highest_pcie_bridge = bridge;
 702		bridge = pci_upstream_bridge(bridge);
 703	}
 704
 705	if (pci_pcie_type(highest_pcie_bridge) != PCI_EXP_TYPE_ROOT_PORT)
 706		return NULL;
 707
 708	return highest_pcie_bridge;
 709}
 710EXPORT_SYMBOL(pci_find_pcie_root_port);
 711
 712/**
 713 * pci_wait_for_pending - wait for @mask bit(s) to clear in status word @pos
 714 * @dev: the PCI device to operate on
 715 * @pos: config space offset of status word
 716 * @mask: mask of bit(s) to care about in status word
 717 *
 718 * Return 1 when mask bit(s) in status word clear, 0 otherwise.
 719 */
 720int pci_wait_for_pending(struct pci_dev *dev, int pos, u16 mask)
 721{
 722	int i;
 723
 724	/* Wait for Transaction Pending bit clean */
 725	for (i = 0; i < 4; i++) {
 726		u16 status;
 727		if (i)
 728			msleep((1 << (i - 1)) * 100);
 729
 730		pci_read_config_word(dev, pos, &status);
 731		if (!(status & mask))
 732			return 1;
 733	}
 734
 735	return 0;
 736}
 737
 738/**
 739 * pci_restore_bars - restore a device's BAR values (e.g. after wake-up)
 740 * @dev: PCI device to have its BARs restored
 741 *
 742 * Restore the BAR values for a given device, so as to make it
 743 * accessible by its driver.
 744 */
 745static void pci_restore_bars(struct pci_dev *dev)
 
 746{
 747	int i;
 748
 749	for (i = 0; i < PCI_BRIDGE_RESOURCES; i++)
 750		pci_update_resource(dev, i);
 751}
 752
 753static const struct pci_platform_pm_ops *pci_platform_pm;
 754
 755int pci_set_platform_pm(const struct pci_platform_pm_ops *ops)
 756{
 757	if (!ops->is_manageable || !ops->set_state  || !ops->get_state ||
 758	    !ops->choose_state  || !ops->set_wakeup || !ops->need_resume)
 759		return -EINVAL;
 760	pci_platform_pm = ops;
 761	return 0;
 762}
 763
 764static inline bool platform_pci_power_manageable(struct pci_dev *dev)
 765{
 766	return pci_platform_pm ? pci_platform_pm->is_manageable(dev) : false;
 767}
 768
 769static inline int platform_pci_set_power_state(struct pci_dev *dev,
 770					       pci_power_t t)
 771{
 772	return pci_platform_pm ? pci_platform_pm->set_state(dev, t) : -ENOSYS;
 773}
 774
 775static inline pci_power_t platform_pci_get_power_state(struct pci_dev *dev)
 776{
 777	return pci_platform_pm ? pci_platform_pm->get_state(dev) : PCI_UNKNOWN;
 778}
 779
 780static inline void platform_pci_refresh_power_state(struct pci_dev *dev)
 781{
 782	if (pci_platform_pm && pci_platform_pm->refresh_state)
 783		pci_platform_pm->refresh_state(dev);
 784}
 785
 786static inline pci_power_t platform_pci_choose_state(struct pci_dev *dev)
 787{
 788	return pci_platform_pm ?
 789			pci_platform_pm->choose_state(dev) : PCI_POWER_ERROR;
 790}
 791
 792static inline int platform_pci_set_wakeup(struct pci_dev *dev, bool enable)
 793{
 794	return pci_platform_pm ?
 795			pci_platform_pm->set_wakeup(dev, enable) : -ENODEV;
 796}
 797
 798static inline bool platform_pci_need_resume(struct pci_dev *dev)
 799{
 800	return pci_platform_pm ? pci_platform_pm->need_resume(dev) : false;
 801}
 802
 803static inline bool platform_pci_bridge_d3(struct pci_dev *dev)
 804{
 805	return pci_platform_pm ? pci_platform_pm->bridge_d3(dev) : false;
 806}
 807
 808/**
 809 * pci_raw_set_power_state - Use PCI PM registers to set the power state of
 810 *			     given PCI device
 811 * @dev: PCI device to handle.
 812 * @state: PCI power state (D0, D1, D2, D3hot) to put the device into.
 813 *
 814 * RETURN VALUE:
 815 * -EINVAL if the requested state is invalid.
 816 * -EIO if device does not support PCI PM or its PM capabilities register has a
 817 * wrong version, or device doesn't support the requested state.
 818 * 0 if device already is in the requested state.
 819 * 0 if device's power state has been successfully changed.
 820 */
 821static int pci_raw_set_power_state(struct pci_dev *dev, pci_power_t state)
 822{
 823	u16 pmcsr;
 824	bool need_restore = false;
 825
 826	/* Check if we're already there */
 827	if (dev->current_state == state)
 828		return 0;
 829
 830	if (!dev->pm_cap)
 831		return -EIO;
 832
 833	if (state < PCI_D0 || state > PCI_D3hot)
 834		return -EINVAL;
 835
 836	/*
 837	 * Validate current state:
 838	 * Can enter D0 from any state, but if we can only go deeper
 839	 * to sleep if we're already in a low power state
 840	 */
 841	if (state != PCI_D0 && dev->current_state <= PCI_D3cold
 842	    && dev->current_state > state) {
 843		pci_err(dev, "invalid power transition (from state %d to %d)\n",
 844			dev->current_state, state);
 845		return -EINVAL;
 846	}
 847
 848	/* Check if this device supports the desired state */
 849	if ((state == PCI_D1 && !dev->d1_support)
 850	   || (state == PCI_D2 && !dev->d2_support))
 851		return -EIO;
 852
 853	pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
 854
 855	/*
 856	 * If we're (effectively) in D3, force entire word to 0.
 857	 * This doesn't affect PME_Status, disables PME_En, and
 858	 * sets PowerState to 0.
 859	 */
 860	switch (dev->current_state) {
 861	case PCI_D0:
 862	case PCI_D1:
 863	case PCI_D2:
 864		pmcsr &= ~PCI_PM_CTRL_STATE_MASK;
 865		pmcsr |= state;
 866		break;
 867	case PCI_D3hot:
 868	case PCI_D3cold:
 869	case PCI_UNKNOWN: /* Boot-up */
 870		if ((pmcsr & PCI_PM_CTRL_STATE_MASK) == PCI_D3hot
 871		 && !(pmcsr & PCI_PM_CTRL_NO_SOFT_RESET))
 872			need_restore = true;
 873		/* Fall-through - force to D0 */
 874	default:
 875		pmcsr = 0;
 876		break;
 877	}
 878
 879	/* Enter specified state */
 880	pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr);
 881
 882	/*
 883	 * Mandatory power management transition delays; see PCI PM 1.1
 884	 * 5.6.1 table 18
 885	 */
 886	if (state == PCI_D3hot || dev->current_state == PCI_D3hot)
 887		pci_dev_d3_sleep(dev);
 888	else if (state == PCI_D2 || dev->current_state == PCI_D2)
 889		udelay(PCI_PM_D2_DELAY);
 890
 891	pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
 892	dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
 893	if (dev->current_state != state)
 894		pci_info_ratelimited(dev, "Refused to change power state, currently in D%d\n",
 895			 dev->current_state);
 896
 897	/*
 898	 * According to section 5.4.1 of the "PCI BUS POWER MANAGEMENT
 899	 * INTERFACE SPECIFICATION, REV. 1.2", a device transitioning
 900	 * from D3hot to D0 _may_ perform an internal reset, thereby
 901	 * going to "D0 Uninitialized" rather than "D0 Initialized".
 902	 * For example, at least some versions of the 3c905B and the
 903	 * 3c556B exhibit this behaviour.
 904	 *
 905	 * At least some laptop BIOSen (e.g. the Thinkpad T21) leave
 906	 * devices in a D3hot state at boot.  Consequently, we need to
 907	 * restore at least the BARs so that the device will be
 908	 * accessible to its driver.
 909	 */
 910	if (need_restore)
 911		pci_restore_bars(dev);
 912
 913	if (dev->bus->self)
 914		pcie_aspm_pm_state_change(dev->bus->self);
 915
 916	return 0;
 917}
 918
 919/**
 920 * pci_update_current_state - Read power state of given device and cache it
 
 921 * @dev: PCI device to handle.
 922 * @state: State to cache in case the device doesn't have the PM capability
 923 *
 924 * The power state is read from the PMCSR register, which however is
 925 * inaccessible in D3cold.  The platform firmware is therefore queried first
 926 * to detect accessibility of the register.  In case the platform firmware
 927 * reports an incorrect state or the device isn't power manageable by the
 928 * platform at all, we try to detect D3cold by testing accessibility of the
 929 * vendor ID in config space.
 930 */
 931void pci_update_current_state(struct pci_dev *dev, pci_power_t state)
 932{
 933	if (platform_pci_get_power_state(dev) == PCI_D3cold ||
 934	    !pci_device_is_present(dev)) {
 935		dev->current_state = PCI_D3cold;
 936	} else if (dev->pm_cap) {
 937		u16 pmcsr;
 938
 
 
 
 
 
 
 
 
 
 
 939		pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
 940		dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
 941	} else {
 942		dev->current_state = state;
 943	}
 944}
 945
 946/**
 947 * pci_refresh_power_state - Refresh the given device's power state data
 948 * @dev: Target PCI device.
 949 *
 950 * Ask the platform to refresh the devices power state information and invoke
 951 * pci_update_current_state() to update its current PCI power state.
 952 */
 953void pci_refresh_power_state(struct pci_dev *dev)
 954{
 955	if (platform_pci_power_manageable(dev))
 956		platform_pci_refresh_power_state(dev);
 957
 958	pci_update_current_state(dev, dev->current_state);
 
 959}
 960
 961/**
 962 * pci_platform_power_transition - Use platform to change device power state
 963 * @dev: PCI device to handle.
 964 * @state: State to put the device into.
 965 */
 966static int pci_platform_power_transition(struct pci_dev *dev, pci_power_t state)
 967{
 968	int error;
 969
 970	if (platform_pci_power_manageable(dev)) {
 971		error = platform_pci_set_power_state(dev, state);
 972		if (!error)
 973			pci_update_current_state(dev, state);
 974	} else
 975		error = -ENODEV;
 976
 977	if (error && !dev->pm_cap) /* Fall back to PCI_D0 */
 978		dev->current_state = PCI_D0;
 979
 980	return error;
 981}
 982
 983/**
 984 * pci_wakeup - Wake up a PCI device
 985 * @pci_dev: Device to handle.
 986 * @ign: ignored parameter
 987 */
 988static int pci_wakeup(struct pci_dev *pci_dev, void *ign)
 989{
 990	pci_wakeup_event(pci_dev);
 991	pm_request_resume(&pci_dev->dev);
 992	return 0;
 993}
 994
 995/**
 996 * pci_wakeup_bus - Walk given bus and wake up devices on it
 997 * @bus: Top bus of the subtree to walk.
 998 */
 999void pci_wakeup_bus(struct pci_bus *bus)
1000{
1001	if (bus)
1002		pci_walk_bus(bus, pci_wakeup, NULL);
1003}
1004
1005/**
1006 * __pci_start_power_transition - Start power transition of a PCI device
1007 * @dev: PCI device to handle.
1008 * @state: State to put the device into.
1009 */
1010static void __pci_start_power_transition(struct pci_dev *dev, pci_power_t state)
1011{
1012	if (state == PCI_D0) {
1013		pci_platform_power_transition(dev, PCI_D0);
1014		/*
1015		 * Mandatory power management transition delays, see
1016		 * PCI Express Base Specification Revision 2.0 Section
1017		 * 6.6.1: Conventional Reset.  Do not delay for
1018		 * devices powered on/off by corresponding bridge,
1019		 * because have already delayed for the bridge.
1020		 */
1021		if (dev->runtime_d3cold) {
1022			if (dev->d3cold_delay && !dev->imm_ready)
1023				msleep(dev->d3cold_delay);
1024			/*
1025			 * When powering on a bridge from D3cold, the
1026			 * whole hierarchy may be powered on into
1027			 * D0uninitialized state, resume them to give
1028			 * them a chance to suspend again
1029			 */
1030			pci_wakeup_bus(dev->subordinate);
1031		}
1032	}
1033}
1034
1035/**
1036 * __pci_dev_set_current_state - Set current state of a PCI device
1037 * @dev: Device to handle
1038 * @data: pointer to state to be set
1039 */
1040static int __pci_dev_set_current_state(struct pci_dev *dev, void *data)
1041{
1042	pci_power_t state = *(pci_power_t *)data;
1043
1044	dev->current_state = state;
1045	return 0;
1046}
1047
1048/**
1049 * pci_bus_set_current_state - Walk given bus and set current state of devices
1050 * @bus: Top bus of the subtree to walk.
1051 * @state: state to be set
1052 */
1053void pci_bus_set_current_state(struct pci_bus *bus, pci_power_t state)
1054{
1055	if (bus)
1056		pci_walk_bus(bus, __pci_dev_set_current_state, &state);
1057}
1058
1059/**
1060 * __pci_complete_power_transition - Complete power transition of a PCI device
1061 * @dev: PCI device to handle.
1062 * @state: State to put the device into.
1063 *
1064 * This function should not be called directly by device drivers.
1065 */
1066int __pci_complete_power_transition(struct pci_dev *dev, pci_power_t state)
1067{
1068	int ret;
1069
1070	if (state <= PCI_D0)
1071		return -EINVAL;
1072	ret = pci_platform_power_transition(dev, state);
1073	/* Power off the bridge may power off the whole hierarchy */
1074	if (!ret && state == PCI_D3cold)
1075		pci_bus_set_current_state(dev->subordinate, PCI_D3cold);
1076	return ret;
1077}
1078EXPORT_SYMBOL_GPL(__pci_complete_power_transition);
1079
1080/**
1081 * pci_set_power_state - Set the power state of a PCI device
1082 * @dev: PCI device to handle.
1083 * @state: PCI power state (D0, D1, D2, D3hot) to put the device into.
1084 *
1085 * Transition a device to a new power state, using the platform firmware and/or
1086 * the device's PCI PM registers.
1087 *
1088 * RETURN VALUE:
1089 * -EINVAL if the requested state is invalid.
1090 * -EIO if device does not support PCI PM or its PM capabilities register has a
1091 * wrong version, or device doesn't support the requested state.
1092 * 0 if the transition is to D1 or D2 but D1 and D2 are not supported.
1093 * 0 if device already is in the requested state.
1094 * 0 if the transition is to D3 but D3 is not supported.
1095 * 0 if device's power state has been successfully changed.
1096 */
1097int pci_set_power_state(struct pci_dev *dev, pci_power_t state)
1098{
1099	int error;
1100
1101	/* Bound the state we're entering */
1102	if (state > PCI_D3cold)
1103		state = PCI_D3cold;
1104	else if (state < PCI_D0)
1105		state = PCI_D0;
1106	else if ((state == PCI_D1 || state == PCI_D2) && pci_no_d1d2(dev))
1107
1108		/*
1109		 * If the device or the parent bridge do not support PCI
1110		 * PM, ignore the request if we're doing anything other
1111		 * than putting it into D0 (which would only happen on
1112		 * boot).
1113		 */
1114		return 0;
1115
1116	/* Check if we're already there */
1117	if (dev->current_state == state)
1118		return 0;
1119
1120	__pci_start_power_transition(dev, state);
1121
1122	/*
1123	 * This device is quirked not to be put into D3, so don't put it in
1124	 * D3
1125	 */
1126	if (state >= PCI_D3hot && (dev->dev_flags & PCI_DEV_FLAGS_NO_D3))
1127		return 0;
1128
1129	/*
1130	 * To put device in D3cold, we put device into D3hot in native
1131	 * way, then put device into D3cold with platform ops
1132	 */
1133	error = pci_raw_set_power_state(dev, state > PCI_D3hot ?
1134					PCI_D3hot : state);
1135
1136	if (!__pci_complete_power_transition(dev, state))
1137		error = 0;
 
 
 
 
 
 
1138
1139	return error;
1140}
1141EXPORT_SYMBOL(pci_set_power_state);
1142
1143/**
1144 * pci_power_up - Put the given device into D0 forcibly
1145 * @dev: PCI device to power up
1146 */
1147void pci_power_up(struct pci_dev *dev)
1148{
1149	__pci_start_power_transition(dev, PCI_D0);
1150	pci_raw_set_power_state(dev, PCI_D0);
1151	pci_update_current_state(dev, PCI_D0);
1152}
1153
1154/**
1155 * pci_choose_state - Choose the power state of a PCI device
1156 * @dev: PCI device to be suspended
1157 * @state: target sleep state for the whole system. This is the value
1158 *	   that is passed to suspend() function.
1159 *
1160 * Returns PCI power state suitable for given device and given system
1161 * message.
1162 */
 
1163pci_power_t pci_choose_state(struct pci_dev *dev, pm_message_t state)
1164{
1165	pci_power_t ret;
1166
1167	if (!dev->pm_cap)
1168		return PCI_D0;
1169
1170	ret = platform_pci_choose_state(dev);
1171	if (ret != PCI_POWER_ERROR)
1172		return ret;
1173
1174	switch (state.event) {
1175	case PM_EVENT_ON:
1176		return PCI_D0;
1177	case PM_EVENT_FREEZE:
1178	case PM_EVENT_PRETHAW:
1179		/* REVISIT both freeze and pre-thaw "should" use D0 */
1180	case PM_EVENT_SUSPEND:
1181	case PM_EVENT_HIBERNATE:
1182		return PCI_D3hot;
1183	default:
1184		pci_info(dev, "unrecognized suspend event %d\n",
1185			 state.event);
1186		BUG();
1187	}
1188	return PCI_D0;
1189}
 
1190EXPORT_SYMBOL(pci_choose_state);
1191
1192#define PCI_EXP_SAVE_REGS	7
1193
 
1194static struct pci_cap_saved_state *_pci_find_saved_cap(struct pci_dev *pci_dev,
1195						       u16 cap, bool extended)
1196{
1197	struct pci_cap_saved_state *tmp;
1198
1199	hlist_for_each_entry(tmp, &pci_dev->saved_cap_space, next) {
1200		if (tmp->cap.cap_extended == extended && tmp->cap.cap_nr == cap)
1201			return tmp;
1202	}
1203	return NULL;
1204}
1205
1206struct pci_cap_saved_state *pci_find_saved_cap(struct pci_dev *dev, char cap)
1207{
1208	return _pci_find_saved_cap(dev, cap, false);
1209}
1210
1211struct pci_cap_saved_state *pci_find_saved_ext_cap(struct pci_dev *dev, u16 cap)
1212{
1213	return _pci_find_saved_cap(dev, cap, true);
1214}
1215
1216static int pci_save_pcie_state(struct pci_dev *dev)
1217{
1218	int i = 0;
1219	struct pci_cap_saved_state *save_state;
1220	u16 *cap;
1221
1222	if (!pci_is_pcie(dev))
1223		return 0;
1224
1225	save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
1226	if (!save_state) {
1227		pci_err(dev, "buffer not found in %s\n", __func__);
1228		return -ENOMEM;
1229	}
1230
1231	cap = (u16 *)&save_state->cap.data[0];
1232	pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &cap[i++]);
1233	pcie_capability_read_word(dev, PCI_EXP_LNKCTL, &cap[i++]);
1234	pcie_capability_read_word(dev, PCI_EXP_SLTCTL, &cap[i++]);
1235	pcie_capability_read_word(dev, PCI_EXP_RTCTL,  &cap[i++]);
1236	pcie_capability_read_word(dev, PCI_EXP_DEVCTL2, &cap[i++]);
1237	pcie_capability_read_word(dev, PCI_EXP_LNKCTL2, &cap[i++]);
1238	pcie_capability_read_word(dev, PCI_EXP_SLTCTL2, &cap[i++]);
1239
1240	return 0;
1241}
1242
1243static void pci_restore_pcie_state(struct pci_dev *dev)
1244{
1245	int i = 0;
1246	struct pci_cap_saved_state *save_state;
1247	u16 *cap;
1248
1249	save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
1250	if (!save_state)
1251		return;
1252
1253	cap = (u16 *)&save_state->cap.data[0];
1254	pcie_capability_write_word(dev, PCI_EXP_DEVCTL, cap[i++]);
1255	pcie_capability_write_word(dev, PCI_EXP_LNKCTL, cap[i++]);
1256	pcie_capability_write_word(dev, PCI_EXP_SLTCTL, cap[i++]);
1257	pcie_capability_write_word(dev, PCI_EXP_RTCTL, cap[i++]);
1258	pcie_capability_write_word(dev, PCI_EXP_DEVCTL2, cap[i++]);
1259	pcie_capability_write_word(dev, PCI_EXP_LNKCTL2, cap[i++]);
1260	pcie_capability_write_word(dev, PCI_EXP_SLTCTL2, cap[i++]);
1261}
1262
 
1263static int pci_save_pcix_state(struct pci_dev *dev)
1264{
1265	int pos;
1266	struct pci_cap_saved_state *save_state;
1267
1268	pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1269	if (!pos)
1270		return 0;
1271
1272	save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX);
1273	if (!save_state) {
1274		pci_err(dev, "buffer not found in %s\n", __func__);
1275		return -ENOMEM;
1276	}
1277
1278	pci_read_config_word(dev, pos + PCI_X_CMD,
1279			     (u16 *)save_state->cap.data);
1280
1281	return 0;
1282}
1283
1284static void pci_restore_pcix_state(struct pci_dev *dev)
1285{
1286	int i = 0, pos;
1287	struct pci_cap_saved_state *save_state;
1288	u16 *cap;
1289
1290	save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX);
1291	pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1292	if (!save_state || !pos)
1293		return;
1294	cap = (u16 *)&save_state->cap.data[0];
1295
1296	pci_write_config_word(dev, pos + PCI_X_CMD, cap[i++]);
1297}
1298
1299static void pci_save_ltr_state(struct pci_dev *dev)
1300{
1301	int ltr;
1302	struct pci_cap_saved_state *save_state;
1303	u16 *cap;
1304
1305	if (!pci_is_pcie(dev))
1306		return;
1307
1308	ltr = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_LTR);
1309	if (!ltr)
1310		return;
1311
1312	save_state = pci_find_saved_ext_cap(dev, PCI_EXT_CAP_ID_LTR);
1313	if (!save_state) {
1314		pci_err(dev, "no suspend buffer for LTR; ASPM issues possible after resume\n");
1315		return;
1316	}
1317
1318	cap = (u16 *)&save_state->cap.data[0];
1319	pci_read_config_word(dev, ltr + PCI_LTR_MAX_SNOOP_LAT, cap++);
1320	pci_read_config_word(dev, ltr + PCI_LTR_MAX_NOSNOOP_LAT, cap++);
1321}
1322
1323static void pci_restore_ltr_state(struct pci_dev *dev)
1324{
1325	struct pci_cap_saved_state *save_state;
1326	int ltr;
1327	u16 *cap;
1328
1329	save_state = pci_find_saved_ext_cap(dev, PCI_EXT_CAP_ID_LTR);
1330	ltr = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_LTR);
1331	if (!save_state || !ltr)
1332		return;
1333
1334	cap = (u16 *)&save_state->cap.data[0];
1335	pci_write_config_word(dev, ltr + PCI_LTR_MAX_SNOOP_LAT, *cap++);
1336	pci_write_config_word(dev, ltr + PCI_LTR_MAX_NOSNOOP_LAT, *cap++);
1337}
1338
1339/**
1340 * pci_save_state - save the PCI configuration space of a device before
1341 *		    suspending
1342 * @dev: PCI device that we're dealing with
1343 */
1344int pci_save_state(struct pci_dev *dev)
 
1345{
1346	int i;
1347	/* XXX: 100% dword access ok here? */
1348	for (i = 0; i < 16; i++)
1349		pci_read_config_dword(dev, i * 4, &dev->saved_config_space[i]);
1350	dev->state_saved = true;
1351
1352	i = pci_save_pcie_state(dev);
1353	if (i != 0)
1354		return i;
1355
1356	i = pci_save_pcix_state(dev);
1357	if (i != 0)
1358		return i;
1359
1360	pci_save_ltr_state(dev);
1361	pci_save_dpc_state(dev);
1362	return pci_save_vc_state(dev);
1363}
1364EXPORT_SYMBOL(pci_save_state);
1365
1366static void pci_restore_config_dword(struct pci_dev *pdev, int offset,
1367				     u32 saved_val, int retry, bool force)
1368{
1369	u32 val;
1370
1371	pci_read_config_dword(pdev, offset, &val);
1372	if (!force && val == saved_val)
1373		return;
1374
1375	for (;;) {
1376		pci_dbg(pdev, "restoring config space at offset %#x (was %#x, writing %#x)\n",
1377			offset, val, saved_val);
1378		pci_write_config_dword(pdev, offset, saved_val);
1379		if (retry-- <= 0)
1380			return;
1381
1382		pci_read_config_dword(pdev, offset, &val);
1383		if (val == saved_val)
1384			return;
1385
1386		mdelay(1);
1387	}
1388}
1389
1390static void pci_restore_config_space_range(struct pci_dev *pdev,
1391					   int start, int end, int retry,
1392					   bool force)
1393{
1394	int index;
1395
1396	for (index = end; index >= start; index--)
1397		pci_restore_config_dword(pdev, 4 * index,
1398					 pdev->saved_config_space[index],
1399					 retry, force);
1400}
1401
1402static void pci_restore_config_space(struct pci_dev *pdev)
1403{
1404	if (pdev->hdr_type == PCI_HEADER_TYPE_NORMAL) {
1405		pci_restore_config_space_range(pdev, 10, 15, 0, false);
1406		/* Restore BARs before the command register. */
1407		pci_restore_config_space_range(pdev, 4, 9, 10, false);
1408		pci_restore_config_space_range(pdev, 0, 3, 0, false);
1409	} else if (pdev->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
1410		pci_restore_config_space_range(pdev, 12, 15, 0, false);
1411
1412		/*
1413		 * Force rewriting of prefetch registers to avoid S3 resume
1414		 * issues on Intel PCI bridges that occur when these
1415		 * registers are not explicitly written.
1416		 */
1417		pci_restore_config_space_range(pdev, 9, 11, 0, true);
1418		pci_restore_config_space_range(pdev, 0, 8, 0, false);
1419	} else {
1420		pci_restore_config_space_range(pdev, 0, 15, 0, false);
1421	}
1422}
1423
1424static void pci_restore_rebar_state(struct pci_dev *pdev)
1425{
1426	unsigned int pos, nbars, i;
1427	u32 ctrl;
1428
1429	pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_REBAR);
1430	if (!pos)
1431		return;
1432
1433	pci_read_config_dword(pdev, pos + PCI_REBAR_CTRL, &ctrl);
1434	nbars = (ctrl & PCI_REBAR_CTRL_NBAR_MASK) >>
1435		    PCI_REBAR_CTRL_NBAR_SHIFT;
1436
1437	for (i = 0; i < nbars; i++, pos += 8) {
1438		struct resource *res;
1439		int bar_idx, size;
1440
1441		pci_read_config_dword(pdev, pos + PCI_REBAR_CTRL, &ctrl);
1442		bar_idx = ctrl & PCI_REBAR_CTRL_BAR_IDX;
1443		res = pdev->resource + bar_idx;
1444		size = ilog2(resource_size(res)) - 20;
1445		ctrl &= ~PCI_REBAR_CTRL_BAR_SIZE;
1446		ctrl |= size << PCI_REBAR_CTRL_BAR_SHIFT;
1447		pci_write_config_dword(pdev, pos + PCI_REBAR_CTRL, ctrl);
1448	}
1449}
1450
1451/**
1452 * pci_restore_state - Restore the saved state of a PCI device
1453 * @dev: PCI device that we're dealing with
1454 */
1455void pci_restore_state(struct pci_dev *dev)
1456{
1457	if (!dev->state_saved)
1458		return;
1459
1460	/*
1461	 * Restore max latencies (in the LTR capability) before enabling
1462	 * LTR itself (in the PCIe capability).
1463	 */
1464	pci_restore_ltr_state(dev);
1465
1466	pci_restore_pcie_state(dev);
1467	pci_restore_pasid_state(dev);
1468	pci_restore_pri_state(dev);
1469	pci_restore_ats_state(dev);
1470	pci_restore_vc_state(dev);
1471	pci_restore_rebar_state(dev);
1472	pci_restore_dpc_state(dev);
1473
1474	pci_cleanup_aer_error_status_regs(dev);
1475
1476	pci_restore_config_space(dev);
1477
1478	pci_restore_pcix_state(dev);
1479	pci_restore_msi_state(dev);
1480
1481	/* Restore ACS and IOV configuration state */
1482	pci_enable_acs(dev);
1483	pci_restore_iov_state(dev);
1484
1485	dev->state_saved = false;
1486}
1487EXPORT_SYMBOL(pci_restore_state);
1488
1489struct pci_saved_state {
1490	u32 config_space[16];
1491	struct pci_cap_saved_data cap[0];
1492};
1493
1494/**
1495 * pci_store_saved_state - Allocate and return an opaque struct containing
1496 *			   the device saved state.
1497 * @dev: PCI device that we're dealing with
1498 *
1499 * Return NULL if no state or error.
1500 */
1501struct pci_saved_state *pci_store_saved_state(struct pci_dev *dev)
1502{
1503	struct pci_saved_state *state;
1504	struct pci_cap_saved_state *tmp;
1505	struct pci_cap_saved_data *cap;
1506	size_t size;
1507
1508	if (!dev->state_saved)
1509		return NULL;
1510
1511	size = sizeof(*state) + sizeof(struct pci_cap_saved_data);
1512
1513	hlist_for_each_entry(tmp, &dev->saved_cap_space, next)
1514		size += sizeof(struct pci_cap_saved_data) + tmp->cap.size;
1515
1516	state = kzalloc(size, GFP_KERNEL);
1517	if (!state)
1518		return NULL;
1519
1520	memcpy(state->config_space, dev->saved_config_space,
1521	       sizeof(state->config_space));
1522
1523	cap = state->cap;
1524	hlist_for_each_entry(tmp, &dev->saved_cap_space, next) {
1525		size_t len = sizeof(struct pci_cap_saved_data) + tmp->cap.size;
1526		memcpy(cap, &tmp->cap, len);
1527		cap = (struct pci_cap_saved_data *)((u8 *)cap + len);
1528	}
1529	/* Empty cap_save terminates list */
1530
1531	return state;
1532}
1533EXPORT_SYMBOL_GPL(pci_store_saved_state);
1534
1535/**
1536 * pci_load_saved_state - Reload the provided save state into struct pci_dev.
1537 * @dev: PCI device that we're dealing with
1538 * @state: Saved state returned from pci_store_saved_state()
1539 */
1540int pci_load_saved_state(struct pci_dev *dev,
1541			 struct pci_saved_state *state)
1542{
1543	struct pci_cap_saved_data *cap;
1544
1545	dev->state_saved = false;
1546
1547	if (!state)
1548		return 0;
1549
1550	memcpy(dev->saved_config_space, state->config_space,
1551	       sizeof(state->config_space));
1552
1553	cap = state->cap;
1554	while (cap->size) {
1555		struct pci_cap_saved_state *tmp;
1556
1557		tmp = _pci_find_saved_cap(dev, cap->cap_nr, cap->cap_extended);
1558		if (!tmp || tmp->cap.size != cap->size)
1559			return -EINVAL;
1560
1561		memcpy(tmp->cap.data, cap->data, tmp->cap.size);
1562		cap = (struct pci_cap_saved_data *)((u8 *)cap +
1563		       sizeof(struct pci_cap_saved_data) + cap->size);
1564	}
1565
1566	dev->state_saved = true;
1567	return 0;
1568}
1569EXPORT_SYMBOL_GPL(pci_load_saved_state);
1570
1571/**
1572 * pci_load_and_free_saved_state - Reload the save state pointed to by state,
1573 *				   and free the memory allocated for it.
1574 * @dev: PCI device that we're dealing with
1575 * @state: Pointer to saved state returned from pci_store_saved_state()
1576 */
1577int pci_load_and_free_saved_state(struct pci_dev *dev,
1578				  struct pci_saved_state **state)
1579{
1580	int ret = pci_load_saved_state(dev, *state);
1581	kfree(*state);
1582	*state = NULL;
1583	return ret;
1584}
1585EXPORT_SYMBOL_GPL(pci_load_and_free_saved_state);
1586
1587int __weak pcibios_enable_device(struct pci_dev *dev, int bars)
1588{
1589	return pci_enable_resources(dev, bars);
1590}
1591
1592static int do_pci_enable_device(struct pci_dev *dev, int bars)
1593{
1594	int err;
1595	struct pci_dev *bridge;
1596	u16 cmd;
1597	u8 pin;
1598
1599	err = pci_set_power_state(dev, PCI_D0);
1600	if (err < 0 && err != -EIO)
1601		return err;
1602
1603	bridge = pci_upstream_bridge(dev);
1604	if (bridge)
1605		pcie_aspm_powersave_config_link(bridge);
1606
1607	err = pcibios_enable_device(dev, bars);
1608	if (err < 0)
1609		return err;
1610	pci_fixup_device(pci_fixup_enable, dev);
1611
1612	if (dev->msi_enabled || dev->msix_enabled)
1613		return 0;
1614
1615	pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
1616	if (pin) {
1617		pci_read_config_word(dev, PCI_COMMAND, &cmd);
1618		if (cmd & PCI_COMMAND_INTX_DISABLE)
1619			pci_write_config_word(dev, PCI_COMMAND,
1620					      cmd & ~PCI_COMMAND_INTX_DISABLE);
1621	}
1622
1623	return 0;
1624}
1625
1626/**
1627 * pci_reenable_device - Resume abandoned device
1628 * @dev: PCI device to be resumed
1629 *
1630 * NOTE: This function is a backend of pci_default_resume() and is not supposed
1631 * to be called by normal code, write proper resume handler and use it instead.
1632 */
1633int pci_reenable_device(struct pci_dev *dev)
1634{
1635	if (pci_is_enabled(dev))
1636		return do_pci_enable_device(dev, (1 << PCI_NUM_RESOURCES) - 1);
1637	return 0;
1638}
1639EXPORT_SYMBOL(pci_reenable_device);
1640
1641static void pci_enable_bridge(struct pci_dev *dev)
1642{
1643	struct pci_dev *bridge;
1644	int retval;
1645
1646	bridge = pci_upstream_bridge(dev);
1647	if (bridge)
1648		pci_enable_bridge(bridge);
1649
1650	if (pci_is_enabled(dev)) {
1651		if (!dev->is_busmaster)
1652			pci_set_master(dev);
1653		return;
1654	}
1655
1656	retval = pci_enable_device(dev);
1657	if (retval)
1658		pci_err(dev, "Error enabling bridge (%d), continuing\n",
1659			retval);
1660	pci_set_master(dev);
1661}
1662
1663static int pci_enable_device_flags(struct pci_dev *dev, unsigned long flags)
1664{
1665	struct pci_dev *bridge;
1666	int err;
1667	int i, bars = 0;
1668
1669	/*
1670	 * Power state could be unknown at this point, either due to a fresh
1671	 * boot or a device removal call.  So get the current power state
1672	 * so that things like MSI message writing will behave as expected
1673	 * (e.g. if the device really is in D0 at enable time).
1674	 */
1675	if (dev->pm_cap) {
1676		u16 pmcsr;
1677		pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
1678		dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
1679	}
1680
1681	if (atomic_inc_return(&dev->enable_cnt) > 1)
1682		return 0;		/* already enabled */
1683
1684	bridge = pci_upstream_bridge(dev);
1685	if (bridge)
1686		pci_enable_bridge(bridge);
1687
1688	/* only skip sriov related */
1689	for (i = 0; i <= PCI_ROM_RESOURCE; i++)
1690		if (dev->resource[i].flags & flags)
1691			bars |= (1 << i);
1692	for (i = PCI_BRIDGE_RESOURCES; i < DEVICE_COUNT_RESOURCE; i++)
1693		if (dev->resource[i].flags & flags)
1694			bars |= (1 << i);
1695
1696	err = do_pci_enable_device(dev, bars);
1697	if (err < 0)
1698		atomic_dec(&dev->enable_cnt);
1699	return err;
1700}
1701
1702/**
1703 * pci_enable_device_io - Initialize a device for use with IO space
1704 * @dev: PCI device to be initialized
1705 *
1706 * Initialize device before it's used by a driver. Ask low-level code
1707 * to enable I/O resources. Wake up the device if it was suspended.
1708 * Beware, this function can fail.
1709 */
1710int pci_enable_device_io(struct pci_dev *dev)
1711{
1712	return pci_enable_device_flags(dev, IORESOURCE_IO);
1713}
1714EXPORT_SYMBOL(pci_enable_device_io);
1715
1716/**
1717 * pci_enable_device_mem - Initialize a device for use with Memory space
1718 * @dev: PCI device to be initialized
1719 *
1720 * Initialize device before it's used by a driver. Ask low-level code
1721 * to enable Memory resources. Wake up the device if it was suspended.
1722 * Beware, this function can fail.
1723 */
1724int pci_enable_device_mem(struct pci_dev *dev)
1725{
1726	return pci_enable_device_flags(dev, IORESOURCE_MEM);
1727}
1728EXPORT_SYMBOL(pci_enable_device_mem);
1729
1730/**
1731 * pci_enable_device - Initialize device before it's used by a driver.
1732 * @dev: PCI device to be initialized
1733 *
1734 * Initialize device before it's used by a driver. Ask low-level code
1735 * to enable I/O and memory. Wake up the device if it was suspended.
1736 * Beware, this function can fail.
1737 *
1738 * Note we don't actually enable the device many times if we call
1739 * this function repeatedly (we just increment the count).
1740 */
1741int pci_enable_device(struct pci_dev *dev)
1742{
1743	return pci_enable_device_flags(dev, IORESOURCE_MEM | IORESOURCE_IO);
1744}
1745EXPORT_SYMBOL(pci_enable_device);
1746
1747/*
1748 * Managed PCI resources.  This manages device on/off, INTx/MSI/MSI-X
1749 * on/off and BAR regions.  pci_dev itself records MSI/MSI-X status, so
1750 * there's no need to track it separately.  pci_devres is initialized
1751 * when a device is enabled using managed PCI device enable interface.
1752 */
1753struct pci_devres {
1754	unsigned int enabled:1;
1755	unsigned int pinned:1;
1756	unsigned int orig_intx:1;
1757	unsigned int restore_intx:1;
1758	unsigned int mwi:1;
1759	u32 region_mask;
1760};
1761
1762static void pcim_release(struct device *gendev, void *res)
1763{
1764	struct pci_dev *dev = to_pci_dev(gendev);
1765	struct pci_devres *this = res;
1766	int i;
1767
1768	if (dev->msi_enabled)
1769		pci_disable_msi(dev);
1770	if (dev->msix_enabled)
1771		pci_disable_msix(dev);
1772
1773	for (i = 0; i < DEVICE_COUNT_RESOURCE; i++)
1774		if (this->region_mask & (1 << i))
1775			pci_release_region(dev, i);
1776
1777	if (this->mwi)
1778		pci_clear_mwi(dev);
1779
1780	if (this->restore_intx)
1781		pci_intx(dev, this->orig_intx);
1782
1783	if (this->enabled && !this->pinned)
1784		pci_disable_device(dev);
1785}
1786
1787static struct pci_devres *get_pci_dr(struct pci_dev *pdev)
1788{
1789	struct pci_devres *dr, *new_dr;
1790
1791	dr = devres_find(&pdev->dev, pcim_release, NULL, NULL);
1792	if (dr)
1793		return dr;
1794
1795	new_dr = devres_alloc(pcim_release, sizeof(*new_dr), GFP_KERNEL);
1796	if (!new_dr)
1797		return NULL;
1798	return devres_get(&pdev->dev, new_dr, NULL, NULL);
1799}
1800
1801static struct pci_devres *find_pci_dr(struct pci_dev *pdev)
1802{
1803	if (pci_is_managed(pdev))
1804		return devres_find(&pdev->dev, pcim_release, NULL, NULL);
1805	return NULL;
1806}
1807
1808/**
1809 * pcim_enable_device - Managed pci_enable_device()
1810 * @pdev: PCI device to be initialized
1811 *
1812 * Managed pci_enable_device().
1813 */
1814int pcim_enable_device(struct pci_dev *pdev)
1815{
1816	struct pci_devres *dr;
1817	int rc;
1818
1819	dr = get_pci_dr(pdev);
1820	if (unlikely(!dr))
1821		return -ENOMEM;
1822	if (dr->enabled)
1823		return 0;
1824
1825	rc = pci_enable_device(pdev);
1826	if (!rc) {
1827		pdev->is_managed = 1;
1828		dr->enabled = 1;
1829	}
1830	return rc;
1831}
1832EXPORT_SYMBOL(pcim_enable_device);
1833
1834/**
1835 * pcim_pin_device - Pin managed PCI device
1836 * @pdev: PCI device to pin
1837 *
1838 * Pin managed PCI device @pdev.  Pinned device won't be disabled on
1839 * driver detach.  @pdev must have been enabled with
1840 * pcim_enable_device().
1841 */
1842void pcim_pin_device(struct pci_dev *pdev)
1843{
1844	struct pci_devres *dr;
1845
1846	dr = find_pci_dr(pdev);
1847	WARN_ON(!dr || !dr->enabled);
1848	if (dr)
1849		dr->pinned = 1;
1850}
1851EXPORT_SYMBOL(pcim_pin_device);
1852
1853/*
1854 * pcibios_add_device - provide arch specific hooks when adding device dev
1855 * @dev: the PCI device being added
1856 *
1857 * Permits the platform to provide architecture specific functionality when
1858 * devices are added. This is the default implementation. Architecture
1859 * implementations can override this.
1860 */
1861int __weak pcibios_add_device(struct pci_dev *dev)
1862{
1863	return 0;
1864}
1865
1866/**
1867 * pcibios_release_device - provide arch specific hooks when releasing
1868 *			    device dev
1869 * @dev: the PCI device being released
1870 *
1871 * Permits the platform to provide architecture specific functionality when
1872 * devices are released. This is the default implementation. Architecture
1873 * implementations can override this.
1874 */
1875void __weak pcibios_release_device(struct pci_dev *dev) {}
1876
1877/**
1878 * pcibios_disable_device - disable arch specific PCI resources for device dev
1879 * @dev: the PCI device to disable
1880 *
1881 * Disables architecture specific PCI resources for the device. This
1882 * is the default implementation. Architecture implementations can
1883 * override this.
1884 */
1885void __weak pcibios_disable_device(struct pci_dev *dev) {}
1886
1887/**
1888 * pcibios_penalize_isa_irq - penalize an ISA IRQ
1889 * @irq: ISA IRQ to penalize
1890 * @active: IRQ active or not
1891 *
1892 * Permits the platform to provide architecture-specific functionality when
1893 * penalizing ISA IRQs. This is the default implementation. Architecture
1894 * implementations can override this.
1895 */
1896void __weak pcibios_penalize_isa_irq(int irq, int active) {}
1897
1898static void do_pci_disable_device(struct pci_dev *dev)
1899{
1900	u16 pci_command;
1901
1902	pci_read_config_word(dev, PCI_COMMAND, &pci_command);
1903	if (pci_command & PCI_COMMAND_MASTER) {
1904		pci_command &= ~PCI_COMMAND_MASTER;
1905		pci_write_config_word(dev, PCI_COMMAND, pci_command);
1906	}
1907
1908	pcibios_disable_device(dev);
1909}
1910
1911/**
1912 * pci_disable_enabled_device - Disable device without updating enable_cnt
1913 * @dev: PCI device to disable
1914 *
1915 * NOTE: This function is a backend of PCI power management routines and is
1916 * not supposed to be called drivers.
1917 */
1918void pci_disable_enabled_device(struct pci_dev *dev)
1919{
1920	if (pci_is_enabled(dev))
1921		do_pci_disable_device(dev);
1922}
1923
1924/**
1925 * pci_disable_device - Disable PCI device after use
1926 * @dev: PCI device to be disabled
1927 *
1928 * Signal to the system that the PCI device is not in use by the system
1929 * anymore.  This only involves disabling PCI bus-mastering, if active.
1930 *
1931 * Note we don't actually disable the device until all callers of
1932 * pci_enable_device() have called pci_disable_device().
1933 */
1934void pci_disable_device(struct pci_dev *dev)
 
1935{
1936	struct pci_devres *dr;
1937
1938	dr = find_pci_dr(dev);
1939	if (dr)
1940		dr->enabled = 0;
1941
1942	dev_WARN_ONCE(&dev->dev, atomic_read(&dev->enable_cnt) <= 0,
1943		      "disabling already-disabled device");
1944
1945	if (atomic_dec_return(&dev->enable_cnt) != 0)
1946		return;
1947
1948	do_pci_disable_device(dev);
1949
1950	dev->is_busmaster = 0;
1951}
1952EXPORT_SYMBOL(pci_disable_device);
1953
1954/**
1955 * pcibios_set_pcie_reset_state - set reset state for device dev
1956 * @dev: the PCIe device reset
1957 * @state: Reset state to enter into
1958 *
1959 * Set the PCIe reset state for the device. This is the default
 
1960 * implementation. Architecture implementations can override this.
1961 */
1962int __weak pcibios_set_pcie_reset_state(struct pci_dev *dev,
1963					enum pcie_reset_state state)
1964{
1965	return -EINVAL;
1966}
1967
1968/**
1969 * pci_set_pcie_reset_state - set reset state for device dev
1970 * @dev: the PCIe device reset
1971 * @state: Reset state to enter into
1972 *
 
1973 * Sets the PCI reset state for the device.
1974 */
1975int pci_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state)
1976{
1977	return pcibios_set_pcie_reset_state(dev, state);
1978}
1979EXPORT_SYMBOL_GPL(pci_set_pcie_reset_state);
1980
1981/**
1982 * pcie_clear_root_pme_status - Clear root port PME interrupt status.
1983 * @dev: PCIe root port or event collector.
1984 */
1985void pcie_clear_root_pme_status(struct pci_dev *dev)
1986{
1987	pcie_capability_set_dword(dev, PCI_EXP_RTSTA, PCI_EXP_RTSTA_PME);
1988}
1989
1990/**
1991 * pci_check_pme_status - Check if given device has generated PME.
1992 * @dev: Device to check.
1993 *
1994 * Check the PME status of the device and if set, clear it and clear PME enable
1995 * (if set).  Return 'true' if PME status and PME enable were both set or
1996 * 'false' otherwise.
1997 */
1998bool pci_check_pme_status(struct pci_dev *dev)
1999{
2000	int pmcsr_pos;
2001	u16 pmcsr;
2002	bool ret = false;
2003
2004	if (!dev->pm_cap)
2005		return false;
2006
2007	pmcsr_pos = dev->pm_cap + PCI_PM_CTRL;
2008	pci_read_config_word(dev, pmcsr_pos, &pmcsr);
2009	if (!(pmcsr & PCI_PM_CTRL_PME_STATUS))
2010		return false;
2011
2012	/* Clear PME status. */
2013	pmcsr |= PCI_PM_CTRL_PME_STATUS;
2014	if (pmcsr & PCI_PM_CTRL_PME_ENABLE) {
2015		/* Disable PME to avoid interrupt flood. */
2016		pmcsr &= ~PCI_PM_CTRL_PME_ENABLE;
2017		ret = true;
2018	}
2019
2020	pci_write_config_word(dev, pmcsr_pos, pmcsr);
2021
2022	return ret;
2023}
2024
2025/**
2026 * pci_pme_wakeup - Wake up a PCI device if its PME Status bit is set.
2027 * @dev: Device to handle.
2028 * @pme_poll_reset: Whether or not to reset the device's pme_poll flag.
2029 *
2030 * Check if @dev has generated PME and queue a resume request for it in that
2031 * case.
2032 */
2033static int pci_pme_wakeup(struct pci_dev *dev, void *pme_poll_reset)
2034{
2035	if (pme_poll_reset && dev->pme_poll)
2036		dev->pme_poll = false;
2037
2038	if (pci_check_pme_status(dev)) {
2039		pci_wakeup_event(dev);
2040		pm_request_resume(&dev->dev);
2041	}
2042	return 0;
2043}
2044
2045/**
2046 * pci_pme_wakeup_bus - Walk given bus and wake up devices on it, if necessary.
2047 * @bus: Top bus of the subtree to walk.
2048 */
2049void pci_pme_wakeup_bus(struct pci_bus *bus)
2050{
2051	if (bus)
2052		pci_walk_bus(bus, pci_pme_wakeup, (void *)true);
2053}
2054
2055
2056/**
2057 * pci_pme_capable - check the capability of PCI device to generate PME#
2058 * @dev: PCI device to handle.
2059 * @state: PCI state from which device will issue PME#.
2060 */
2061bool pci_pme_capable(struct pci_dev *dev, pci_power_t state)
2062{
2063	if (!dev->pm_cap)
2064		return false;
2065
2066	return !!(dev->pme_support & (1 << state));
2067}
2068EXPORT_SYMBOL(pci_pme_capable);
2069
2070static void pci_pme_list_scan(struct work_struct *work)
2071{
2072	struct pci_pme_device *pme_dev, *n;
2073
2074	mutex_lock(&pci_pme_list_mutex);
2075	list_for_each_entry_safe(pme_dev, n, &pci_pme_list, list) {
2076		if (pme_dev->dev->pme_poll) {
2077			struct pci_dev *bridge;
2078
2079			bridge = pme_dev->dev->bus->self;
2080			/*
2081			 * If bridge is in low power state, the
2082			 * configuration space of subordinate devices
2083			 * may be not accessible
2084			 */
2085			if (bridge && bridge->current_state != PCI_D0)
2086				continue;
2087			/*
2088			 * If the device is in D3cold it should not be
2089			 * polled either.
2090			 */
2091			if (pme_dev->dev->current_state == PCI_D3cold)
2092				continue;
2093
2094			pci_pme_wakeup(pme_dev->dev, NULL);
2095		} else {
2096			list_del(&pme_dev->list);
2097			kfree(pme_dev);
2098		}
2099	}
2100	if (!list_empty(&pci_pme_list))
2101		queue_delayed_work(system_freezable_wq, &pci_pme_work,
2102				   msecs_to_jiffies(PME_TIMEOUT));
2103	mutex_unlock(&pci_pme_list_mutex);
2104}
2105
2106static void __pci_pme_active(struct pci_dev *dev, bool enable)
 
 
 
 
 
 
 
 
2107{
2108	u16 pmcsr;
2109
2110	if (!dev->pme_support)
2111		return;
2112
2113	pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
2114	/* Clear PME_Status by writing 1 to it and enable PME# */
2115	pmcsr |= PCI_PM_CTRL_PME_STATUS | PCI_PM_CTRL_PME_ENABLE;
2116	if (!enable)
2117		pmcsr &= ~PCI_PM_CTRL_PME_ENABLE;
2118
2119	pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr);
2120}
2121
2122/**
2123 * pci_pme_restore - Restore PME configuration after config space restore.
2124 * @dev: PCI device to update.
2125 */
2126void pci_pme_restore(struct pci_dev *dev)
2127{
2128	u16 pmcsr;
2129
2130	if (!dev->pme_support)
2131		return;
2132
2133	pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
2134	if (dev->wakeup_prepared) {
2135		pmcsr |= PCI_PM_CTRL_PME_ENABLE;
2136		pmcsr &= ~PCI_PM_CTRL_PME_STATUS;
2137	} else {
2138		pmcsr &= ~PCI_PM_CTRL_PME_ENABLE;
2139		pmcsr |= PCI_PM_CTRL_PME_STATUS;
2140	}
2141	pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr);
2142}
2143
2144/**
2145 * pci_pme_active - enable or disable PCI device's PME# function
2146 * @dev: PCI device to handle.
2147 * @enable: 'true' to enable PME# generation; 'false' to disable it.
2148 *
2149 * The caller must verify that the device is capable of generating PME# before
2150 * calling this function with @enable equal to 'true'.
2151 */
2152void pci_pme_active(struct pci_dev *dev, bool enable)
2153{
2154	__pci_pme_active(dev, enable);
2155
2156	/*
2157	 * PCI (as opposed to PCIe) PME requires that the device have
2158	 * its PME# line hooked up correctly. Not all hardware vendors
2159	 * do this, so the PME never gets delivered and the device
2160	 * remains asleep. The easiest way around this is to
2161	 * periodically walk the list of suspended devices and check
2162	 * whether any have their PME flag set. The assumption is that
2163	 * we'll wake up often enough anyway that this won't be a huge
2164	 * hit, and the power savings from the devices will still be a
2165	 * win.
2166	 *
2167	 * Although PCIe uses in-band PME message instead of PME# line
2168	 * to report PME, PME does not work for some PCIe devices in
2169	 * reality.  For example, there are devices that set their PME
2170	 * status bits, but don't really bother to send a PME message;
2171	 * there are PCI Express Root Ports that don't bother to
2172	 * trigger interrupts when they receive PME messages from the
2173	 * devices below.  So PME poll is used for PCIe devices too.
2174	 */
2175
2176	if (dev->pme_poll) {
2177		struct pci_pme_device *pme_dev;
2178		if (enable) {
2179			pme_dev = kmalloc(sizeof(struct pci_pme_device),
2180					  GFP_KERNEL);
2181			if (!pme_dev) {
2182				pci_warn(dev, "can't enable PME#\n");
2183				return;
2184			}
2185			pme_dev->dev = dev;
2186			mutex_lock(&pci_pme_list_mutex);
2187			list_add(&pme_dev->list, &pci_pme_list);
2188			if (list_is_singular(&pci_pme_list))
2189				queue_delayed_work(system_freezable_wq,
2190						   &pci_pme_work,
2191						   msecs_to_jiffies(PME_TIMEOUT));
2192			mutex_unlock(&pci_pme_list_mutex);
2193		} else {
2194			mutex_lock(&pci_pme_list_mutex);
2195			list_for_each_entry(pme_dev, &pci_pme_list, list) {
2196				if (pme_dev->dev == dev) {
2197					list_del(&pme_dev->list);
2198					kfree(pme_dev);
2199					break;
2200				}
2201			}
2202			mutex_unlock(&pci_pme_list_mutex);
2203		}
2204	}
2205
2206	pci_dbg(dev, "PME# %s\n", enable ? "enabled" : "disabled");
2207}
2208EXPORT_SYMBOL(pci_pme_active);
2209
2210/**
2211 * __pci_enable_wake - enable PCI device as wakeup event source
2212 * @dev: PCI device affected
2213 * @state: PCI state from which device will issue wakeup events
 
2214 * @enable: True to enable event generation; false to disable
2215 *
2216 * This enables the device as a wakeup event source, or disables it.
2217 * When such events involves platform-specific hooks, those hooks are
2218 * called automatically by this routine.
2219 *
2220 * Devices with legacy power management (no standard PCI PM capabilities)
2221 * always require such platform hooks.
2222 *
2223 * RETURN VALUE:
2224 * 0 is returned on success
2225 * -EINVAL is returned if device is not supposed to wake up the system
2226 * Error code depending on the platform is returned if both the platform and
2227 * the native mechanism fail to enable the generation of wake-up events
2228 */
2229static int __pci_enable_wake(struct pci_dev *dev, pci_power_t state, bool enable)
 
2230{
2231	int ret = 0;
2232
2233	/*
2234	 * Bridges that are not power-manageable directly only signal
2235	 * wakeup on behalf of subordinate devices which is set up
2236	 * elsewhere, so skip them. However, bridges that are
2237	 * power-manageable may signal wakeup for themselves (for example,
2238	 * on a hotplug event) and they need to be covered here.
2239	 */
2240	if (!pci_power_manageable(dev))
2241		return 0;
2242
2243	/* Don't do the same thing twice in a row for one device. */
2244	if (!!enable == !!dev->wakeup_prepared)
2245		return 0;
2246
2247	/*
2248	 * According to "PCI System Architecture" 4th ed. by Tom Shanley & Don
2249	 * Anderson we should be doing PME# wake enable followed by ACPI wake
2250	 * enable.  To disable wake-up we call the platform first, for symmetry.
2251	 */
2252
2253	if (enable) {
2254		int error;
2255
2256		if (pci_pme_capable(dev, state))
2257			pci_pme_active(dev, true);
2258		else
2259			ret = 1;
2260		error = platform_pci_set_wakeup(dev, true);
 
2261		if (ret)
2262			ret = error;
2263		if (!ret)
2264			dev->wakeup_prepared = true;
2265	} else {
2266		platform_pci_set_wakeup(dev, false);
 
 
 
2267		pci_pme_active(dev, false);
2268		dev->wakeup_prepared = false;
2269	}
2270
2271	return ret;
2272}
2273
2274/**
2275 * pci_enable_wake - change wakeup settings for a PCI device
2276 * @pci_dev: Target device
2277 * @state: PCI state from which device will issue wakeup events
2278 * @enable: Whether or not to enable event generation
2279 *
2280 * If @enable is set, check device_may_wakeup() for the device before calling
2281 * __pci_enable_wake() for it.
2282 */
2283int pci_enable_wake(struct pci_dev *pci_dev, pci_power_t state, bool enable)
2284{
2285	if (enable && !device_may_wakeup(&pci_dev->dev))
2286		return -EINVAL;
2287
2288	return __pci_enable_wake(pci_dev, state, enable);
2289}
2290EXPORT_SYMBOL(pci_enable_wake);
2291
2292/**
2293 * pci_wake_from_d3 - enable/disable device to wake up from D3_hot or D3_cold
2294 * @dev: PCI device to prepare
2295 * @enable: True to enable wake-up event generation; false to disable
2296 *
2297 * Many drivers want the device to wake up the system from D3_hot or D3_cold
2298 * and this function allows them to set that up cleanly - pci_enable_wake()
2299 * should not be called twice in a row to enable wake-up due to PCI PM vs ACPI
2300 * ordering constraints.
2301 *
2302 * This function only returns error code if the device is not allowed to wake
2303 * up the system from sleep or it is not capable of generating PME# from both
2304 * D3_hot and D3_cold and the platform is unable to enable wake-up power for it.
2305 */
2306int pci_wake_from_d3(struct pci_dev *dev, bool enable)
2307{
2308	return pci_pme_capable(dev, PCI_D3cold) ?
2309			pci_enable_wake(dev, PCI_D3cold, enable) :
2310			pci_enable_wake(dev, PCI_D3hot, enable);
2311}
2312EXPORT_SYMBOL(pci_wake_from_d3);
2313
2314/**
2315 * pci_target_state - find an appropriate low power state for a given PCI dev
2316 * @dev: PCI device
2317 * @wakeup: Whether or not wakeup functionality will be enabled for the device.
2318 *
2319 * Use underlying platform code to find a supported low power state for @dev.
2320 * If the platform can't manage @dev, return the deepest state from which it
2321 * can generate wake events, based on any available PME info.
2322 */
2323static pci_power_t pci_target_state(struct pci_dev *dev, bool wakeup)
2324{
2325	pci_power_t target_state = PCI_D3hot;
2326
2327	if (platform_pci_power_manageable(dev)) {
2328		/*
2329		 * Call the platform to find the target state for the device.
 
2330		 */
2331		pci_power_t state = platform_pci_choose_state(dev);
2332
2333		switch (state) {
2334		case PCI_POWER_ERROR:
2335		case PCI_UNKNOWN:
2336			break;
2337		case PCI_D1:
2338		case PCI_D2:
2339			if (pci_no_d1d2(dev))
2340				break;
2341			/* else, fall through */
2342		default:
2343			target_state = state;
2344		}
2345
2346		return target_state;
2347	}
2348
2349	if (!dev->pm_cap)
2350		target_state = PCI_D0;
2351
2352	/*
2353	 * If the device is in D3cold even though it's not power-manageable by
2354	 * the platform, it may have been powered down by non-standard means.
2355	 * Best to let it slumber.
2356	 */
2357	if (dev->current_state == PCI_D3cold)
2358		target_state = PCI_D3cold;
2359
2360	if (wakeup) {
2361		/*
2362		 * Find the deepest state from which the device can generate
2363		 * PME#.
 
2364		 */
2365		if (dev->pme_support) {
2366			while (target_state
2367			      && !(dev->pme_support & (1 << target_state)))
2368				target_state--;
2369		}
2370	}
2371
2372	return target_state;
2373}
2374
2375/**
2376 * pci_prepare_to_sleep - prepare PCI device for system-wide transition
2377 *			  into a sleep state
2378 * @dev: Device to handle.
2379 *
2380 * Choose the power state appropriate for the device depending on whether
2381 * it can wake up the system and/or is power manageable by the platform
2382 * (PCI_D3hot is the default) and put the device into that state.
2383 */
2384int pci_prepare_to_sleep(struct pci_dev *dev)
2385{
2386	bool wakeup = device_may_wakeup(&dev->dev);
2387	pci_power_t target_state = pci_target_state(dev, wakeup);
2388	int error;
2389
2390	if (target_state == PCI_POWER_ERROR)
2391		return -EIO;
2392
2393	pci_enable_wake(dev, target_state, wakeup);
 
 
 
 
2394
2395	error = pci_set_power_state(dev, target_state);
2396
2397	if (error)
2398		pci_enable_wake(dev, target_state, false);
2399
2400	return error;
2401}
2402EXPORT_SYMBOL(pci_prepare_to_sleep);
2403
2404/**
2405 * pci_back_from_sleep - turn PCI device on during system-wide transition
2406 *			 into working state
2407 * @dev: Device to handle.
2408 *
2409 * Disable device's system wake-up capability and put it into D0.
2410 */
2411int pci_back_from_sleep(struct pci_dev *dev)
2412{
2413	pci_enable_wake(dev, PCI_D0, false);
2414	return pci_set_power_state(dev, PCI_D0);
2415}
2416EXPORT_SYMBOL(pci_back_from_sleep);
2417
2418/**
2419 * pci_finish_runtime_suspend - Carry out PCI-specific part of runtime suspend.
2420 * @dev: PCI device being suspended.
2421 *
2422 * Prepare @dev to generate wake-up events at run time and put it into a low
2423 * power state.
2424 */
2425int pci_finish_runtime_suspend(struct pci_dev *dev)
2426{
2427	pci_power_t target_state;
2428	int error;
2429
2430	target_state = pci_target_state(dev, device_can_wakeup(&dev->dev));
2431	if (target_state == PCI_POWER_ERROR)
2432		return -EIO;
2433
2434	dev->runtime_d3cold = target_state == PCI_D3cold;
2435
2436	__pci_enable_wake(dev, target_state, pci_dev_run_wake(dev));
2437
2438	error = pci_set_power_state(dev, target_state);
2439
2440	if (error) {
2441		pci_enable_wake(dev, target_state, false);
2442		dev->runtime_d3cold = false;
2443	}
2444
2445	return error;
2446}
2447
2448/**
2449 * pci_dev_run_wake - Check if device can generate run-time wake-up events.
2450 * @dev: Device to check.
2451 *
2452 * Return true if the device itself is capable of generating wake-up events
2453 * (through the platform or using the native PCIe PME) or if the device supports
2454 * PME and one of its upstream bridges can generate wake-up events.
2455 */
2456bool pci_dev_run_wake(struct pci_dev *dev)
2457{
2458	struct pci_bus *bus = dev->bus;
2459
2460	if (!dev->pme_support)
2461		return false;
2462
2463	/* PME-capable in principle, but not from the target power state */
2464	if (!pci_pme_capable(dev, pci_target_state(dev, true)))
2465		return false;
2466
2467	if (device_can_wakeup(&dev->dev))
2468		return true;
2469
2470	while (bus->parent) {
2471		struct pci_dev *bridge = bus->self;
2472
2473		if (device_can_wakeup(&bridge->dev))
2474			return true;
2475
2476		bus = bus->parent;
2477	}
2478
2479	/* We have reached the root bus. */
2480	if (bus->bridge)
2481		return device_can_wakeup(bus->bridge);
2482
2483	return false;
2484}
2485EXPORT_SYMBOL_GPL(pci_dev_run_wake);
2486
2487/**
2488 * pci_dev_need_resume - Check if it is necessary to resume the device.
2489 * @pci_dev: Device to check.
2490 *
2491 * Return 'true' if the device is not runtime-suspended or it has to be
2492 * reconfigured due to wakeup settings difference between system and runtime
2493 * suspend, or the current power state of it is not suitable for the upcoming
2494 * (system-wide) transition.
2495 */
2496bool pci_dev_need_resume(struct pci_dev *pci_dev)
2497{
2498	struct device *dev = &pci_dev->dev;
2499	pci_power_t target_state;
2500
2501	if (!pm_runtime_suspended(dev) || platform_pci_need_resume(pci_dev))
2502		return true;
2503
2504	target_state = pci_target_state(pci_dev, device_may_wakeup(dev));
2505
2506	/*
2507	 * If the earlier platform check has not triggered, D3cold is just power
2508	 * removal on top of D3hot, so no need to resume the device in that
2509	 * case.
2510	 */
2511	return target_state != pci_dev->current_state &&
2512		target_state != PCI_D3cold &&
2513		pci_dev->current_state != PCI_D3hot;
2514}
2515
2516/**
2517 * pci_dev_adjust_pme - Adjust PME setting for a suspended device.
2518 * @pci_dev: Device to check.
2519 *
2520 * If the device is suspended and it is not configured for system wakeup,
2521 * disable PME for it to prevent it from waking up the system unnecessarily.
2522 *
2523 * Note that if the device's power state is D3cold and the platform check in
2524 * pci_dev_need_resume() has not triggered, the device's configuration need not
2525 * be changed.
2526 */
2527void pci_dev_adjust_pme(struct pci_dev *pci_dev)
2528{
2529	struct device *dev = &pci_dev->dev;
2530
2531	spin_lock_irq(&dev->power.lock);
2532
2533	if (pm_runtime_suspended(dev) && !device_may_wakeup(dev) &&
2534	    pci_dev->current_state < PCI_D3cold)
2535		__pci_pme_active(pci_dev, false);
2536
2537	spin_unlock_irq(&dev->power.lock);
2538}
2539
2540/**
2541 * pci_dev_complete_resume - Finalize resume from system sleep for a device.
2542 * @pci_dev: Device to handle.
2543 *
2544 * If the device is runtime suspended and wakeup-capable, enable PME for it as
2545 * it might have been disabled during the prepare phase of system suspend if
2546 * the device was not configured for system wakeup.
2547 */
2548void pci_dev_complete_resume(struct pci_dev *pci_dev)
2549{
2550	struct device *dev = &pci_dev->dev;
2551
2552	if (!pci_dev_run_wake(pci_dev))
2553		return;
2554
2555	spin_lock_irq(&dev->power.lock);
2556
2557	if (pm_runtime_suspended(dev) && pci_dev->current_state < PCI_D3cold)
2558		__pci_pme_active(pci_dev, true);
2559
2560	spin_unlock_irq(&dev->power.lock);
2561}
2562
2563void pci_config_pm_runtime_get(struct pci_dev *pdev)
2564{
2565	struct device *dev = &pdev->dev;
2566	struct device *parent = dev->parent;
2567
2568	if (parent)
2569		pm_runtime_get_sync(parent);
2570	pm_runtime_get_noresume(dev);
2571	/*
2572	 * pdev->current_state is set to PCI_D3cold during suspending,
2573	 * so wait until suspending completes
2574	 */
2575	pm_runtime_barrier(dev);
2576	/*
2577	 * Only need to resume devices in D3cold, because config
2578	 * registers are still accessible for devices suspended but
2579	 * not in D3cold.
2580	 */
2581	if (pdev->current_state == PCI_D3cold)
2582		pm_runtime_resume(dev);
2583}
2584
2585void pci_config_pm_runtime_put(struct pci_dev *pdev)
2586{
2587	struct device *dev = &pdev->dev;
2588	struct device *parent = dev->parent;
2589
2590	pm_runtime_put(dev);
2591	if (parent)
2592		pm_runtime_put_sync(parent);
2593}
2594
2595static const struct dmi_system_id bridge_d3_blacklist[] = {
2596#ifdef CONFIG_X86
2597	{
2598		/*
2599		 * Gigabyte X299 root port is not marked as hotplug capable
2600		 * which allows Linux to power manage it.  However, this
2601		 * confuses the BIOS SMI handler so don't power manage root
2602		 * ports on that system.
2603		 */
2604		.ident = "X299 DESIGNARE EX-CF",
2605		.matches = {
2606			DMI_MATCH(DMI_BOARD_VENDOR, "Gigabyte Technology Co., Ltd."),
2607			DMI_MATCH(DMI_BOARD_NAME, "X299 DESIGNARE EX-CF"),
2608		},
2609	},
2610#endif
2611	{ }
2612};
2613
2614/**
2615 * pci_bridge_d3_possible - Is it possible to put the bridge into D3
2616 * @bridge: Bridge to check
2617 *
2618 * This function checks if it is possible to move the bridge to D3.
2619 * Currently we only allow D3 for recent enough PCIe ports and Thunderbolt.
2620 */
2621bool pci_bridge_d3_possible(struct pci_dev *bridge)
2622{
2623	if (!pci_is_pcie(bridge))
2624		return false;
2625
2626	switch (pci_pcie_type(bridge)) {
2627	case PCI_EXP_TYPE_ROOT_PORT:
2628	case PCI_EXP_TYPE_UPSTREAM:
2629	case PCI_EXP_TYPE_DOWNSTREAM:
2630		if (pci_bridge_d3_disable)
2631			return false;
2632
2633		/*
2634		 * Hotplug ports handled by firmware in System Management Mode
2635		 * may not be put into D3 by the OS (Thunderbolt on non-Macs).
2636		 */
2637		if (bridge->is_hotplug_bridge && !pciehp_is_native(bridge))
2638			return false;
2639
2640		if (pci_bridge_d3_force)
2641			return true;
2642
2643		/* Even the oldest 2010 Thunderbolt controller supports D3. */
2644		if (bridge->is_thunderbolt)
2645			return true;
2646
2647		/* Platform might know better if the bridge supports D3 */
2648		if (platform_pci_bridge_d3(bridge))
2649			return true;
2650
2651		/*
2652		 * Hotplug ports handled natively by the OS were not validated
2653		 * by vendors for runtime D3 at least until 2018 because there
2654		 * was no OS support.
2655		 */
2656		if (bridge->is_hotplug_bridge)
2657			return false;
2658
2659		if (dmi_check_system(bridge_d3_blacklist))
2660			return false;
2661
2662		/*
2663		 * It should be safe to put PCIe ports from 2015 or newer
2664		 * to D3.
2665		 */
2666		if (dmi_get_bios_year() >= 2015)
2667			return true;
2668		break;
2669	}
2670
2671	return false;
2672}
2673
2674static int pci_dev_check_d3cold(struct pci_dev *dev, void *data)
2675{
2676	bool *d3cold_ok = data;
2677
2678	if (/* The device needs to be allowed to go D3cold ... */
2679	    dev->no_d3cold || !dev->d3cold_allowed ||
2680
2681	    /* ... and if it is wakeup capable to do so from D3cold. */
2682	    (device_may_wakeup(&dev->dev) &&
2683	     !pci_pme_capable(dev, PCI_D3cold)) ||
2684
2685	    /* If it is a bridge it must be allowed to go to D3. */
2686	    !pci_power_manageable(dev))
2687
2688		*d3cold_ok = false;
2689
2690	return !*d3cold_ok;
2691}
2692
2693/*
2694 * pci_bridge_d3_update - Update bridge D3 capabilities
2695 * @dev: PCI device which is changed
2696 *
2697 * Update upstream bridge PM capabilities accordingly depending on if the
2698 * device PM configuration was changed or the device is being removed.  The
2699 * change is also propagated upstream.
2700 */
2701void pci_bridge_d3_update(struct pci_dev *dev)
2702{
2703	bool remove = !device_is_registered(&dev->dev);
2704	struct pci_dev *bridge;
2705	bool d3cold_ok = true;
2706
2707	bridge = pci_upstream_bridge(dev);
2708	if (!bridge || !pci_bridge_d3_possible(bridge))
2709		return;
2710
2711	/*
2712	 * If D3 is currently allowed for the bridge, removing one of its
2713	 * children won't change that.
2714	 */
2715	if (remove && bridge->bridge_d3)
2716		return;
2717
2718	/*
2719	 * If D3 is currently allowed for the bridge and a child is added or
2720	 * changed, disallowance of D3 can only be caused by that child, so
2721	 * we only need to check that single device, not any of its siblings.
2722	 *
2723	 * If D3 is currently not allowed for the bridge, checking the device
2724	 * first may allow us to skip checking its siblings.
2725	 */
2726	if (!remove)
2727		pci_dev_check_d3cold(dev, &d3cold_ok);
2728
2729	/*
2730	 * If D3 is currently not allowed for the bridge, this may be caused
2731	 * either by the device being changed/removed or any of its siblings,
2732	 * so we need to go through all children to find out if one of them
2733	 * continues to block D3.
2734	 */
2735	if (d3cold_ok && !bridge->bridge_d3)
2736		pci_walk_bus(bridge->subordinate, pci_dev_check_d3cold,
2737			     &d3cold_ok);
2738
2739	if (bridge->bridge_d3 != d3cold_ok) {
2740		bridge->bridge_d3 = d3cold_ok;
2741		/* Propagate change to upstream bridges */
2742		pci_bridge_d3_update(bridge);
2743	}
2744}
2745
2746/**
2747 * pci_d3cold_enable - Enable D3cold for device
2748 * @dev: PCI device to handle
2749 *
2750 * This function can be used in drivers to enable D3cold from the device
2751 * they handle.  It also updates upstream PCI bridge PM capabilities
2752 * accordingly.
2753 */
2754void pci_d3cold_enable(struct pci_dev *dev)
2755{
2756	if (dev->no_d3cold) {
2757		dev->no_d3cold = false;
2758		pci_bridge_d3_update(dev);
2759	}
2760}
2761EXPORT_SYMBOL_GPL(pci_d3cold_enable);
2762
2763/**
2764 * pci_d3cold_disable - Disable D3cold for device
2765 * @dev: PCI device to handle
2766 *
2767 * This function can be used in drivers to disable D3cold from the device
2768 * they handle.  It also updates upstream PCI bridge PM capabilities
2769 * accordingly.
2770 */
2771void pci_d3cold_disable(struct pci_dev *dev)
2772{
2773	if (!dev->no_d3cold) {
2774		dev->no_d3cold = true;
2775		pci_bridge_d3_update(dev);
2776	}
2777}
2778EXPORT_SYMBOL_GPL(pci_d3cold_disable);
2779
2780/**
2781 * pci_pm_init - Initialize PM functions of given PCI device
2782 * @dev: PCI device to handle.
2783 */
2784void pci_pm_init(struct pci_dev *dev)
2785{
2786	int pm;
2787	u16 status;
2788	u16 pmc;
2789
2790	pm_runtime_forbid(&dev->dev);
2791	pm_runtime_set_active(&dev->dev);
2792	pm_runtime_enable(&dev->dev);
2793	device_enable_async_suspend(&dev->dev);
2794	dev->wakeup_prepared = false;
2795
2796	dev->pm_cap = 0;
2797	dev->pme_support = 0;
2798
2799	/* find PCI PM capability in list */
2800	pm = pci_find_capability(dev, PCI_CAP_ID_PM);
2801	if (!pm)
2802		return;
2803	/* Check device's ability to generate PME# */
2804	pci_read_config_word(dev, pm + PCI_PM_PMC, &pmc);
2805
2806	if ((pmc & PCI_PM_CAP_VER_MASK) > 3) {
2807		pci_err(dev, "unsupported PM cap regs version (%u)\n",
2808			pmc & PCI_PM_CAP_VER_MASK);
2809		return;
2810	}
2811
2812	dev->pm_cap = pm;
2813	dev->d3_delay = PCI_PM_D3_WAIT;
2814	dev->d3cold_delay = PCI_PM_D3COLD_WAIT;
2815	dev->bridge_d3 = pci_bridge_d3_possible(dev);
2816	dev->d3cold_allowed = true;
2817
2818	dev->d1_support = false;
2819	dev->d2_support = false;
2820	if (!pci_no_d1d2(dev)) {
2821		if (pmc & PCI_PM_CAP_D1)
2822			dev->d1_support = true;
2823		if (pmc & PCI_PM_CAP_D2)
2824			dev->d2_support = true;
2825
2826		if (dev->d1_support || dev->d2_support)
2827			pci_info(dev, "supports%s%s\n",
2828				   dev->d1_support ? " D1" : "",
2829				   dev->d2_support ? " D2" : "");
2830	}
2831
2832	pmc &= PCI_PM_CAP_PME_MASK;
2833	if (pmc) {
2834		pci_info(dev, "PME# supported from%s%s%s%s%s\n",
 
2835			 (pmc & PCI_PM_CAP_PME_D0) ? " D0" : "",
2836			 (pmc & PCI_PM_CAP_PME_D1) ? " D1" : "",
2837			 (pmc & PCI_PM_CAP_PME_D2) ? " D2" : "",
2838			 (pmc & PCI_PM_CAP_PME_D3) ? " D3hot" : "",
2839			 (pmc & PCI_PM_CAP_PME_D3cold) ? " D3cold" : "");
2840		dev->pme_support = pmc >> PCI_PM_CAP_PME_SHIFT;
2841		dev->pme_poll = true;
2842		/*
2843		 * Make device's PM flags reflect the wake-up capability, but
2844		 * let the user space enable it to wake up the system as needed.
2845		 */
2846		device_set_wakeup_capable(&dev->dev, true);
2847		/* Disable the PME# generation functionality */
2848		pci_pme_active(dev, false);
2849	}
2850
2851	pci_read_config_word(dev, PCI_STATUS, &status);
2852	if (status & PCI_STATUS_IMM_READY)
2853		dev->imm_ready = 1;
2854}
2855
2856static unsigned long pci_ea_flags(struct pci_dev *dev, u8 prop)
2857{
2858	unsigned long flags = IORESOURCE_PCI_FIXED | IORESOURCE_PCI_EA_BEI;
2859
2860	switch (prop) {
2861	case PCI_EA_P_MEM:
2862	case PCI_EA_P_VF_MEM:
2863		flags |= IORESOURCE_MEM;
2864		break;
2865	case PCI_EA_P_MEM_PREFETCH:
2866	case PCI_EA_P_VF_MEM_PREFETCH:
2867		flags |= IORESOURCE_MEM | IORESOURCE_PREFETCH;
2868		break;
2869	case PCI_EA_P_IO:
2870		flags |= IORESOURCE_IO;
2871		break;
2872	default:
2873		return 0;
2874	}
2875
2876	return flags;
2877}
2878
2879static struct resource *pci_ea_get_resource(struct pci_dev *dev, u8 bei,
2880					    u8 prop)
2881{
2882	if (bei <= PCI_EA_BEI_BAR5 && prop <= PCI_EA_P_IO)
2883		return &dev->resource[bei];
2884#ifdef CONFIG_PCI_IOV
2885	else if (bei >= PCI_EA_BEI_VF_BAR0 && bei <= PCI_EA_BEI_VF_BAR5 &&
2886		 (prop == PCI_EA_P_VF_MEM || prop == PCI_EA_P_VF_MEM_PREFETCH))
2887		return &dev->resource[PCI_IOV_RESOURCES +
2888				      bei - PCI_EA_BEI_VF_BAR0];
2889#endif
2890	else if (bei == PCI_EA_BEI_ROM)
2891		return &dev->resource[PCI_ROM_RESOURCE];
2892	else
2893		return NULL;
2894}
2895
2896/* Read an Enhanced Allocation (EA) entry */
2897static int pci_ea_read(struct pci_dev *dev, int offset)
2898{
2899	struct resource *res;
2900	int ent_size, ent_offset = offset;
2901	resource_size_t start, end;
2902	unsigned long flags;
2903	u32 dw0, bei, base, max_offset;
2904	u8 prop;
2905	bool support_64 = (sizeof(resource_size_t) >= 8);
2906
2907	pci_read_config_dword(dev, ent_offset, &dw0);
2908	ent_offset += 4;
2909
2910	/* Entry size field indicates DWORDs after 1st */
2911	ent_size = ((dw0 & PCI_EA_ES) + 1) << 2;
2912
2913	if (!(dw0 & PCI_EA_ENABLE)) /* Entry not enabled */
2914		goto out;
2915
2916	bei = (dw0 & PCI_EA_BEI) >> 4;
2917	prop = (dw0 & PCI_EA_PP) >> 8;
2918
2919	/*
2920	 * If the Property is in the reserved range, try the Secondary
2921	 * Property instead.
2922	 */
2923	if (prop > PCI_EA_P_BRIDGE_IO && prop < PCI_EA_P_MEM_RESERVED)
2924		prop = (dw0 & PCI_EA_SP) >> 16;
2925	if (prop > PCI_EA_P_BRIDGE_IO)
2926		goto out;
2927
2928	res = pci_ea_get_resource(dev, bei, prop);
2929	if (!res) {
2930		pci_err(dev, "Unsupported EA entry BEI: %u\n", bei);
2931		goto out;
2932	}
2933
2934	flags = pci_ea_flags(dev, prop);
2935	if (!flags) {
2936		pci_err(dev, "Unsupported EA properties: %#x\n", prop);
2937		goto out;
2938	}
2939
2940	/* Read Base */
2941	pci_read_config_dword(dev, ent_offset, &base);
2942	start = (base & PCI_EA_FIELD_MASK);
2943	ent_offset += 4;
2944
2945	/* Read MaxOffset */
2946	pci_read_config_dword(dev, ent_offset, &max_offset);
2947	ent_offset += 4;
2948
2949	/* Read Base MSBs (if 64-bit entry) */
2950	if (base & PCI_EA_IS_64) {
2951		u32 base_upper;
2952
2953		pci_read_config_dword(dev, ent_offset, &base_upper);
2954		ent_offset += 4;
2955
2956		flags |= IORESOURCE_MEM_64;
2957
2958		/* entry starts above 32-bit boundary, can't use */
2959		if (!support_64 && base_upper)
2960			goto out;
2961
2962		if (support_64)
2963			start |= ((u64)base_upper << 32);
2964	}
2965
2966	end = start + (max_offset | 0x03);
2967
2968	/* Read MaxOffset MSBs (if 64-bit entry) */
2969	if (max_offset & PCI_EA_IS_64) {
2970		u32 max_offset_upper;
2971
2972		pci_read_config_dword(dev, ent_offset, &max_offset_upper);
2973		ent_offset += 4;
2974
2975		flags |= IORESOURCE_MEM_64;
2976
2977		/* entry too big, can't use */
2978		if (!support_64 && max_offset_upper)
2979			goto out;
2980
2981		if (support_64)
2982			end += ((u64)max_offset_upper << 32);
2983	}
2984
2985	if (end < start) {
2986		pci_err(dev, "EA Entry crosses address boundary\n");
2987		goto out;
2988	}
2989
2990	if (ent_size != ent_offset - offset) {
2991		pci_err(dev, "EA Entry Size (%d) does not match length read (%d)\n",
2992			ent_size, ent_offset - offset);
2993		goto out;
2994	}
2995
2996	res->name = pci_name(dev);
2997	res->start = start;
2998	res->end = end;
2999	res->flags = flags;
3000
3001	if (bei <= PCI_EA_BEI_BAR5)
3002		pci_info(dev, "BAR %d: %pR (from Enhanced Allocation, properties %#02x)\n",
3003			   bei, res, prop);
3004	else if (bei == PCI_EA_BEI_ROM)
3005		pci_info(dev, "ROM: %pR (from Enhanced Allocation, properties %#02x)\n",
3006			   res, prop);
3007	else if (bei >= PCI_EA_BEI_VF_BAR0 && bei <= PCI_EA_BEI_VF_BAR5)
3008		pci_info(dev, "VF BAR %d: %pR (from Enhanced Allocation, properties %#02x)\n",
3009			   bei - PCI_EA_BEI_VF_BAR0, res, prop);
3010	else
3011		pci_info(dev, "BEI %d res: %pR (from Enhanced Allocation, properties %#02x)\n",
3012			   bei, res, prop);
3013
3014out:
3015	return offset + ent_size;
3016}
3017
3018/* Enhanced Allocation Initialization */
3019void pci_ea_init(struct pci_dev *dev)
3020{
3021	int ea;
3022	u8 num_ent;
3023	int offset;
3024	int i;
3025
3026	/* find PCI EA capability in list */
3027	ea = pci_find_capability(dev, PCI_CAP_ID_EA);
3028	if (!ea)
3029		return;
3030
3031	/* determine the number of entries */
3032	pci_bus_read_config_byte(dev->bus, dev->devfn, ea + PCI_EA_NUM_ENT,
3033					&num_ent);
3034	num_ent &= PCI_EA_NUM_ENT_MASK;
3035
3036	offset = ea + PCI_EA_FIRST_ENT;
3037
3038	/* Skip DWORD 2 for type 1 functions */
3039	if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE)
3040		offset += 4;
3041
3042	/* parse each EA entry */
3043	for (i = 0; i < num_ent; ++i)
3044		offset = pci_ea_read(dev, offset);
3045}
3046
3047static void pci_add_saved_cap(struct pci_dev *pci_dev,
3048	struct pci_cap_saved_state *new_cap)
3049{
3050	hlist_add_head(&new_cap->next, &pci_dev->saved_cap_space);
3051}
3052
3053/**
3054 * _pci_add_cap_save_buffer - allocate buffer for saving given
3055 *			      capability registers
3056 * @dev: the PCI device
3057 * @cap: the capability to allocate the buffer for
3058 * @extended: Standard or Extended capability ID
3059 * @size: requested size of the buffer
3060 */
3061static int _pci_add_cap_save_buffer(struct pci_dev *dev, u16 cap,
3062				    bool extended, unsigned int size)
3063{
3064	int pos;
3065	struct pci_cap_saved_state *save_state;
3066
3067	if (extended)
3068		pos = pci_find_ext_capability(dev, cap);
3069	else
3070		pos = pci_find_capability(dev, cap);
3071
3072	if (!pos)
3073		return 0;
3074
3075	save_state = kzalloc(sizeof(*save_state) + size, GFP_KERNEL);
3076	if (!save_state)
3077		return -ENOMEM;
3078
3079	save_state->cap.cap_nr = cap;
3080	save_state->cap.cap_extended = extended;
3081	save_state->cap.size = size;
3082	pci_add_saved_cap(dev, save_state);
3083
3084	return 0;
3085}
3086
3087int pci_add_cap_save_buffer(struct pci_dev *dev, char cap, unsigned int size)
3088{
3089	return _pci_add_cap_save_buffer(dev, cap, false, size);
3090}
3091
3092int pci_add_ext_cap_save_buffer(struct pci_dev *dev, u16 cap, unsigned int size)
3093{
3094	return _pci_add_cap_save_buffer(dev, cap, true, size);
3095}
3096
3097/**
3098 * pci_allocate_cap_save_buffers - allocate buffers for saving capabilities
3099 * @dev: the PCI device
3100 */
3101void pci_allocate_cap_save_buffers(struct pci_dev *dev)
3102{
3103	int error;
3104
3105	error = pci_add_cap_save_buffer(dev, PCI_CAP_ID_EXP,
3106					PCI_EXP_SAVE_REGS * sizeof(u16));
3107	if (error)
3108		pci_err(dev, "unable to preallocate PCI Express save buffer\n");
 
3109
3110	error = pci_add_cap_save_buffer(dev, PCI_CAP_ID_PCIX, sizeof(u16));
3111	if (error)
3112		pci_err(dev, "unable to preallocate PCI-X save buffer\n");
3113
3114	error = pci_add_ext_cap_save_buffer(dev, PCI_EXT_CAP_ID_LTR,
3115					    2 * sizeof(u16));
3116	if (error)
3117		pci_err(dev, "unable to allocate suspend buffer for LTR\n");
3118
3119	pci_allocate_vc_save_buffers(dev);
3120}
3121
3122void pci_free_cap_save_buffers(struct pci_dev *dev)
3123{
3124	struct pci_cap_saved_state *tmp;
3125	struct hlist_node *n;
3126
3127	hlist_for_each_entry_safe(tmp, n, &dev->saved_cap_space, next)
3128		kfree(tmp);
3129}
3130
3131/**
3132 * pci_configure_ari - enable or disable ARI forwarding
3133 * @dev: the PCI device
3134 *
3135 * If @dev and its upstream bridge both support ARI, enable ARI in the
3136 * bridge.  Otherwise, disable ARI in the bridge.
3137 */
3138void pci_configure_ari(struct pci_dev *dev)
3139{
3140	u32 cap;
3141	struct pci_dev *bridge;
3142
3143	if (pcie_ari_disabled || !pci_is_pcie(dev) || dev->devfn)
3144		return;
3145
3146	bridge = dev->bus->self;
3147	if (!bridge)
3148		return;
3149
3150	pcie_capability_read_dword(bridge, PCI_EXP_DEVCAP2, &cap);
3151	if (!(cap & PCI_EXP_DEVCAP2_ARI))
3152		return;
3153
3154	if (pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI)) {
3155		pcie_capability_set_word(bridge, PCI_EXP_DEVCTL2,
3156					 PCI_EXP_DEVCTL2_ARI);
3157		bridge->ari_enabled = 1;
3158	} else {
3159		pcie_capability_clear_word(bridge, PCI_EXP_DEVCTL2,
3160					   PCI_EXP_DEVCTL2_ARI);
3161		bridge->ari_enabled = 0;
3162	}
3163}
3164
3165static int pci_acs_enable;
3166
3167/**
3168 * pci_request_acs - ask for ACS to be enabled if supported
3169 */
3170void pci_request_acs(void)
3171{
3172	pci_acs_enable = 1;
3173}
3174
3175static const char *disable_acs_redir_param;
3176
3177/**
3178 * pci_disable_acs_redir - disable ACS redirect capabilities
3179 * @dev: the PCI device
3180 *
3181 * For only devices specified in the disable_acs_redir parameter.
3182 */
3183static void pci_disable_acs_redir(struct pci_dev *dev)
3184{
3185	int ret = 0;
3186	const char *p;
3187	int pos;
3188	u16 ctrl;
3189
3190	if (!disable_acs_redir_param)
3191		return;
3192
3193	p = disable_acs_redir_param;
3194	while (*p) {
3195		ret = pci_dev_str_match(dev, p, &p);
3196		if (ret < 0) {
3197			pr_info_once("PCI: Can't parse disable_acs_redir parameter: %s\n",
3198				     disable_acs_redir_param);
3199
3200			break;
3201		} else if (ret == 1) {
3202			/* Found a match */
3203			break;
3204		}
3205
3206		if (*p != ';' && *p != ',') {
3207			/* End of param or invalid format */
3208			break;
3209		}
3210		p++;
3211	}
3212
3213	if (ret != 1)
3214		return;
3215
3216	if (!pci_dev_specific_disable_acs_redir(dev))
3217		return;
3218
3219	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ACS);
3220	if (!pos) {
3221		pci_warn(dev, "cannot disable ACS redirect for this hardware as it does not have ACS capabilities\n");
3222		return;
3223	}
3224
3225	pci_read_config_word(dev, pos + PCI_ACS_CTRL, &ctrl);
3226
3227	/* P2P Request & Completion Redirect */
3228	ctrl &= ~(PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_EC);
3229
3230	pci_write_config_word(dev, pos + PCI_ACS_CTRL, ctrl);
3231
3232	pci_info(dev, "disabled ACS redirect\n");
3233}
3234
3235/**
3236 * pci_std_enable_acs - enable ACS on devices using standard ACS capabilities
3237 * @dev: the PCI device
3238 */
3239static void pci_std_enable_acs(struct pci_dev *dev)
3240{
3241	int pos;
3242	u16 cap;
3243	u16 ctrl;
3244
3245	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ACS);
3246	if (!pos)
3247		return;
3248
3249	pci_read_config_word(dev, pos + PCI_ACS_CAP, &cap);
3250	pci_read_config_word(dev, pos + PCI_ACS_CTRL, &ctrl);
3251
3252	/* Source Validation */
3253	ctrl |= (cap & PCI_ACS_SV);
3254
3255	/* P2P Request Redirect */
3256	ctrl |= (cap & PCI_ACS_RR);
3257
3258	/* P2P Completion Redirect */
3259	ctrl |= (cap & PCI_ACS_CR);
3260
3261	/* Upstream Forwarding */
3262	ctrl |= (cap & PCI_ACS_UF);
3263
3264	pci_write_config_word(dev, pos + PCI_ACS_CTRL, ctrl);
 
 
3265}
3266
3267/**
3268 * pci_enable_acs - enable ACS if hardware support it
3269 * @dev: the PCI device
3270 */
3271void pci_enable_acs(struct pci_dev *dev)
3272{
3273	if (!pci_acs_enable)
3274		goto disable_acs_redir;
3275
3276	if (!pci_dev_specific_enable_acs(dev))
3277		goto disable_acs_redir;
3278
3279	pci_std_enable_acs(dev);
 
3280
3281disable_acs_redir:
3282	/*
3283	 * Note: pci_disable_acs_redir() must be called even if ACS was not
3284	 * enabled by the kernel because it may have been enabled by
3285	 * platform firmware.  So if we are told to disable it, we should
3286	 * always disable it after setting the kernel's default
3287	 * preferences.
3288	 */
3289	pci_disable_acs_redir(dev);
3290}
3291
3292static bool pci_acs_flags_enabled(struct pci_dev *pdev, u16 acs_flags)
3293{
3294	int pos;
3295	u16 cap, ctrl;
3296
3297	pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_ACS);
3298	if (!pos)
3299		return false;
3300
3301	/*
3302	 * Except for egress control, capabilities are either required
3303	 * or only required if controllable.  Features missing from the
3304	 * capability field can therefore be assumed as hard-wired enabled.
3305	 */
3306	pci_read_config_word(pdev, pos + PCI_ACS_CAP, &cap);
3307	acs_flags &= (cap | PCI_ACS_EC);
3308
3309	pci_read_config_word(pdev, pos + PCI_ACS_CTRL, &ctrl);
3310	return (ctrl & acs_flags) == acs_flags;
3311}
3312
3313/**
3314 * pci_acs_enabled - test ACS against required flags for a given device
3315 * @pdev: device to test
3316 * @acs_flags: required PCI ACS flags
3317 *
3318 * Return true if the device supports the provided flags.  Automatically
3319 * filters out flags that are not implemented on multifunction devices.
3320 *
3321 * Note that this interface checks the effective ACS capabilities of the
3322 * device rather than the actual capabilities.  For instance, most single
3323 * function endpoints are not required to support ACS because they have no
3324 * opportunity for peer-to-peer access.  We therefore return 'true'
3325 * regardless of whether the device exposes an ACS capability.  This makes
3326 * it much easier for callers of this function to ignore the actual type
3327 * or topology of the device when testing ACS support.
3328 */
3329bool pci_acs_enabled(struct pci_dev *pdev, u16 acs_flags)
3330{
3331	int ret;
3332
3333	ret = pci_dev_specific_acs_enabled(pdev, acs_flags);
3334	if (ret >= 0)
3335		return ret > 0;
3336
3337	/*
3338	 * Conventional PCI and PCI-X devices never support ACS, either
3339	 * effectively or actually.  The shared bus topology implies that
3340	 * any device on the bus can receive or snoop DMA.
3341	 */
3342	if (!pci_is_pcie(pdev))
3343		return false;
3344
3345	switch (pci_pcie_type(pdev)) {
3346	/*
3347	 * PCI/X-to-PCIe bridges are not specifically mentioned by the spec,
3348	 * but since their primary interface is PCI/X, we conservatively
3349	 * handle them as we would a non-PCIe device.
3350	 */
3351	case PCI_EXP_TYPE_PCIE_BRIDGE:
3352	/*
3353	 * PCIe 3.0, 6.12.1 excludes ACS on these devices.  "ACS is never
3354	 * applicable... must never implement an ACS Extended Capability...".
3355	 * This seems arbitrary, but we take a conservative interpretation
3356	 * of this statement.
3357	 */
3358	case PCI_EXP_TYPE_PCI_BRIDGE:
3359	case PCI_EXP_TYPE_RC_EC:
3360		return false;
3361	/*
3362	 * PCIe 3.0, 6.12.1.1 specifies that downstream and root ports should
3363	 * implement ACS in order to indicate their peer-to-peer capabilities,
3364	 * regardless of whether they are single- or multi-function devices.
3365	 */
3366	case PCI_EXP_TYPE_DOWNSTREAM:
3367	case PCI_EXP_TYPE_ROOT_PORT:
3368		return pci_acs_flags_enabled(pdev, acs_flags);
3369	/*
3370	 * PCIe 3.0, 6.12.1.2 specifies ACS capabilities that should be
3371	 * implemented by the remaining PCIe types to indicate peer-to-peer
3372	 * capabilities, but only when they are part of a multifunction
3373	 * device.  The footnote for section 6.12 indicates the specific
3374	 * PCIe types included here.
3375	 */
3376	case PCI_EXP_TYPE_ENDPOINT:
3377	case PCI_EXP_TYPE_UPSTREAM:
3378	case PCI_EXP_TYPE_LEG_END:
3379	case PCI_EXP_TYPE_RC_END:
3380		if (!pdev->multifunction)
3381			break;
3382
3383		return pci_acs_flags_enabled(pdev, acs_flags);
3384	}
3385
3386	/*
3387	 * PCIe 3.0, 6.12.1.3 specifies no ACS capabilities are applicable
3388	 * to single function devices with the exception of downstream ports.
3389	 */
3390	return true;
3391}
3392
3393/**
3394 * pci_acs_path_enable - test ACS flags from start to end in a hierarchy
3395 * @start: starting downstream device
3396 * @end: ending upstream device or NULL to search to the root bus
3397 * @acs_flags: required flags
3398 *
3399 * Walk up a device tree from start to end testing PCI ACS support.  If
3400 * any step along the way does not support the required flags, return false.
3401 */
3402bool pci_acs_path_enabled(struct pci_dev *start,
3403			  struct pci_dev *end, u16 acs_flags)
3404{
3405	struct pci_dev *pdev, *parent = start;
3406
3407	do {
3408		pdev = parent;
3409
3410		if (!pci_acs_enabled(pdev, acs_flags))
3411			return false;
3412
3413		if (pci_is_root_bus(pdev->bus))
3414			return (end == NULL);
3415
3416		parent = pdev->bus->self;
3417	} while (pdev != end);
3418
3419	return true;
3420}
3421
3422/**
3423 * pci_rebar_find_pos - find position of resize ctrl reg for BAR
3424 * @pdev: PCI device
3425 * @bar: BAR to find
3426 *
3427 * Helper to find the position of the ctrl register for a BAR.
3428 * Returns -ENOTSUPP if resizable BARs are not supported at all.
3429 * Returns -ENOENT if no ctrl register for the BAR could be found.
3430 */
3431static int pci_rebar_find_pos(struct pci_dev *pdev, int bar)
3432{
3433	unsigned int pos, nbars, i;
3434	u32 ctrl;
3435
3436	pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_REBAR);
3437	if (!pos)
3438		return -ENOTSUPP;
3439
3440	pci_read_config_dword(pdev, pos + PCI_REBAR_CTRL, &ctrl);
3441	nbars = (ctrl & PCI_REBAR_CTRL_NBAR_MASK) >>
3442		    PCI_REBAR_CTRL_NBAR_SHIFT;
3443
3444	for (i = 0; i < nbars; i++, pos += 8) {
3445		int bar_idx;
3446
3447		pci_read_config_dword(pdev, pos + PCI_REBAR_CTRL, &ctrl);
3448		bar_idx = ctrl & PCI_REBAR_CTRL_BAR_IDX;
3449		if (bar_idx == bar)
3450			return pos;
3451	}
3452
3453	return -ENOENT;
3454}
3455
3456/**
3457 * pci_rebar_get_possible_sizes - get possible sizes for BAR
3458 * @pdev: PCI device
3459 * @bar: BAR to query
3460 *
3461 * Get the possible sizes of a resizable BAR as bitmask defined in the spec
3462 * (bit 0=1MB, bit 19=512GB). Returns 0 if BAR isn't resizable.
3463 */
3464u32 pci_rebar_get_possible_sizes(struct pci_dev *pdev, int bar)
3465{
3466	int pos;
3467	u32 cap;
3468
3469	pos = pci_rebar_find_pos(pdev, bar);
3470	if (pos < 0)
3471		return 0;
3472
3473	pci_read_config_dword(pdev, pos + PCI_REBAR_CAP, &cap);
3474	return (cap & PCI_REBAR_CAP_SIZES) >> 4;
3475}
3476
3477/**
3478 * pci_rebar_get_current_size - get the current size of a BAR
3479 * @pdev: PCI device
3480 * @bar: BAR to set size to
3481 *
3482 * Read the size of a BAR from the resizable BAR config.
3483 * Returns size if found or negative error code.
3484 */
3485int pci_rebar_get_current_size(struct pci_dev *pdev, int bar)
3486{
3487	int pos;
3488	u32 ctrl;
3489
3490	pos = pci_rebar_find_pos(pdev, bar);
3491	if (pos < 0)
3492		return pos;
3493
3494	pci_read_config_dword(pdev, pos + PCI_REBAR_CTRL, &ctrl);
3495	return (ctrl & PCI_REBAR_CTRL_BAR_SIZE) >> PCI_REBAR_CTRL_BAR_SHIFT;
3496}
3497
3498/**
3499 * pci_rebar_set_size - set a new size for a BAR
3500 * @pdev: PCI device
3501 * @bar: BAR to set size to
3502 * @size: new size as defined in the spec (0=1MB, 19=512GB)
3503 *
3504 * Set the new size of a BAR as defined in the spec.
3505 * Returns zero if resizing was successful, error code otherwise.
3506 */
3507int pci_rebar_set_size(struct pci_dev *pdev, int bar, int size)
3508{
3509	int pos;
3510	u32 ctrl;
3511
3512	pos = pci_rebar_find_pos(pdev, bar);
3513	if (pos < 0)
3514		return pos;
3515
3516	pci_read_config_dword(pdev, pos + PCI_REBAR_CTRL, &ctrl);
3517	ctrl &= ~PCI_REBAR_CTRL_BAR_SIZE;
3518	ctrl |= size << PCI_REBAR_CTRL_BAR_SHIFT;
3519	pci_write_config_dword(pdev, pos + PCI_REBAR_CTRL, ctrl);
3520	return 0;
3521}
3522
3523/**
3524 * pci_enable_atomic_ops_to_root - enable AtomicOp requests to root port
3525 * @dev: the PCI device
3526 * @cap_mask: mask of desired AtomicOp sizes, including one or more of:
3527 *	PCI_EXP_DEVCAP2_ATOMIC_COMP32
3528 *	PCI_EXP_DEVCAP2_ATOMIC_COMP64
3529 *	PCI_EXP_DEVCAP2_ATOMIC_COMP128
3530 *
3531 * Return 0 if all upstream bridges support AtomicOp routing, egress
3532 * blocking is disabled on all upstream ports, and the root port supports
3533 * the requested completion capabilities (32-bit, 64-bit and/or 128-bit
3534 * AtomicOp completion), or negative otherwise.
3535 */
3536int pci_enable_atomic_ops_to_root(struct pci_dev *dev, u32 cap_mask)
3537{
3538	struct pci_bus *bus = dev->bus;
3539	struct pci_dev *bridge;
3540	u32 cap, ctl2;
3541
3542	if (!pci_is_pcie(dev))
3543		return -EINVAL;
3544
3545	/*
3546	 * Per PCIe r4.0, sec 6.15, endpoints and root ports may be
3547	 * AtomicOp requesters.  For now, we only support endpoints as
3548	 * requesters and root ports as completers.  No endpoints as
3549	 * completers, and no peer-to-peer.
3550	 */
3551
3552	switch (pci_pcie_type(dev)) {
3553	case PCI_EXP_TYPE_ENDPOINT:
3554	case PCI_EXP_TYPE_LEG_END:
3555	case PCI_EXP_TYPE_RC_END:
3556		break;
3557	default:
3558		return -EINVAL;
3559	}
3560
3561	while (bus->parent) {
3562		bridge = bus->self;
3563
3564		pcie_capability_read_dword(bridge, PCI_EXP_DEVCAP2, &cap);
3565
3566		switch (pci_pcie_type(bridge)) {
3567		/* Ensure switch ports support AtomicOp routing */
3568		case PCI_EXP_TYPE_UPSTREAM:
3569		case PCI_EXP_TYPE_DOWNSTREAM:
3570			if (!(cap & PCI_EXP_DEVCAP2_ATOMIC_ROUTE))
3571				return -EINVAL;
3572			break;
3573
3574		/* Ensure root port supports all the sizes we care about */
3575		case PCI_EXP_TYPE_ROOT_PORT:
3576			if ((cap & cap_mask) != cap_mask)
3577				return -EINVAL;
3578			break;
3579		}
3580
3581		/* Ensure upstream ports don't block AtomicOps on egress */
3582		if (pci_pcie_type(bridge) == PCI_EXP_TYPE_UPSTREAM) {
3583			pcie_capability_read_dword(bridge, PCI_EXP_DEVCTL2,
3584						   &ctl2);
3585			if (ctl2 & PCI_EXP_DEVCTL2_ATOMIC_EGRESS_BLOCK)
3586				return -EINVAL;
3587		}
3588
3589		bus = bus->parent;
3590	}
3591
3592	pcie_capability_set_word(dev, PCI_EXP_DEVCTL2,
3593				 PCI_EXP_DEVCTL2_ATOMIC_REQ);
3594	return 0;
3595}
3596EXPORT_SYMBOL(pci_enable_atomic_ops_to_root);
3597
3598/**
3599 * pci_swizzle_interrupt_pin - swizzle INTx for device behind bridge
3600 * @dev: the PCI device
3601 * @pin: the INTx pin (1=INTA, 2=INTB, 3=INTC, 4=INTD)
3602 *
3603 * Perform INTx swizzling for a device behind one level of bridge.  This is
3604 * required by section 9.1 of the PCI-to-PCI bridge specification for devices
3605 * behind bridges on add-in cards.  For devices with ARI enabled, the slot
3606 * number is always 0 (see the Implementation Note in section 2.2.8.1 of
3607 * the PCI Express Base Specification, Revision 2.1)
3608 */
3609u8 pci_swizzle_interrupt_pin(const struct pci_dev *dev, u8 pin)
3610{
3611	int slot;
3612
3613	if (pci_ari_enabled(dev->bus))
3614		slot = 0;
3615	else
3616		slot = PCI_SLOT(dev->devfn);
3617
3618	return (((pin - 1) + slot) % 4) + 1;
3619}
3620
3621int pci_get_interrupt_pin(struct pci_dev *dev, struct pci_dev **bridge)
 
3622{
3623	u8 pin;
3624
3625	pin = dev->pin;
3626	if (!pin)
3627		return -1;
3628
3629	while (!pci_is_root_bus(dev->bus)) {
3630		pin = pci_swizzle_interrupt_pin(dev, pin);
3631		dev = dev->bus->self;
3632	}
3633	*bridge = dev;
3634	return pin;
3635}
3636
3637/**
3638 * pci_common_swizzle - swizzle INTx all the way to root bridge
3639 * @dev: the PCI device
3640 * @pinp: pointer to the INTx pin value (1=INTA, 2=INTB, 3=INTD, 4=INTD)
3641 *
3642 * Perform INTx swizzling for a device.  This traverses through all PCI-to-PCI
3643 * bridges all the way up to a PCI root bus.
3644 */
3645u8 pci_common_swizzle(struct pci_dev *dev, u8 *pinp)
3646{
3647	u8 pin = *pinp;
3648
3649	while (!pci_is_root_bus(dev->bus)) {
3650		pin = pci_swizzle_interrupt_pin(dev, pin);
3651		dev = dev->bus->self;
3652	}
3653	*pinp = pin;
3654	return PCI_SLOT(dev->devfn);
3655}
3656EXPORT_SYMBOL_GPL(pci_common_swizzle);
3657
3658/**
3659 * pci_release_region - Release a PCI bar
3660 * @pdev: PCI device whose resources were previously reserved by
3661 *	  pci_request_region()
3662 * @bar: BAR to release
3663 *
3664 * Releases the PCI I/O and memory resources previously reserved by a
3665 * successful call to pci_request_region().  Call this function only
3666 * after all use of the PCI regions has ceased.
3667 */
3668void pci_release_region(struct pci_dev *pdev, int bar)
3669{
3670	struct pci_devres *dr;
3671
3672	if (pci_resource_len(pdev, bar) == 0)
3673		return;
3674	if (pci_resource_flags(pdev, bar) & IORESOURCE_IO)
3675		release_region(pci_resource_start(pdev, bar),
3676				pci_resource_len(pdev, bar));
3677	else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM)
3678		release_mem_region(pci_resource_start(pdev, bar),
3679				pci_resource_len(pdev, bar));
3680
3681	dr = find_pci_dr(pdev);
3682	if (dr)
3683		dr->region_mask &= ~(1 << bar);
3684}
3685EXPORT_SYMBOL(pci_release_region);
3686
3687/**
3688 * __pci_request_region - Reserved PCI I/O and memory resource
3689 * @pdev: PCI device whose resources are to be reserved
3690 * @bar: BAR to be reserved
3691 * @res_name: Name to be associated with resource.
3692 * @exclusive: whether the region access is exclusive or not
3693 *
3694 * Mark the PCI region associated with PCI device @pdev BAR @bar as
3695 * being reserved by owner @res_name.  Do not access any
3696 * address inside the PCI regions unless this call returns
3697 * successfully.
3698 *
3699 * If @exclusive is set, then the region is marked so that userspace
3700 * is explicitly not allowed to map the resource via /dev/mem or
3701 * sysfs MMIO access.
3702 *
3703 * Returns 0 on success, or %EBUSY on error.  A warning
3704 * message is also printed on failure.
3705 */
3706static int __pci_request_region(struct pci_dev *pdev, int bar,
3707				const char *res_name, int exclusive)
3708{
3709	struct pci_devres *dr;
3710
3711	if (pci_resource_len(pdev, bar) == 0)
3712		return 0;
3713
3714	if (pci_resource_flags(pdev, bar) & IORESOURCE_IO) {
3715		if (!request_region(pci_resource_start(pdev, bar),
3716			    pci_resource_len(pdev, bar), res_name))
3717			goto err_out;
3718	} else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM) {
 
3719		if (!__request_mem_region(pci_resource_start(pdev, bar),
3720					pci_resource_len(pdev, bar), res_name,
3721					exclusive))
3722			goto err_out;
3723	}
3724
3725	dr = find_pci_dr(pdev);
3726	if (dr)
3727		dr->region_mask |= 1 << bar;
3728
3729	return 0;
3730
3731err_out:
3732	pci_warn(pdev, "BAR %d: can't reserve %pR\n", bar,
3733		 &pdev->resource[bar]);
3734	return -EBUSY;
3735}
3736
3737/**
3738 * pci_request_region - Reserve PCI I/O and memory resource
3739 * @pdev: PCI device whose resources are to be reserved
3740 * @bar: BAR to be reserved
3741 * @res_name: Name to be associated with resource
3742 *
3743 * Mark the PCI region associated with PCI device @pdev BAR @bar as
3744 * being reserved by owner @res_name.  Do not access any
3745 * address inside the PCI regions unless this call returns
3746 * successfully.
3747 *
3748 * Returns 0 on success, or %EBUSY on error.  A warning
3749 * message is also printed on failure.
3750 */
3751int pci_request_region(struct pci_dev *pdev, int bar, const char *res_name)
3752{
3753	return __pci_request_region(pdev, bar, res_name, 0);
3754}
3755EXPORT_SYMBOL(pci_request_region);
3756
3757/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3758 * pci_release_selected_regions - Release selected PCI I/O and memory resources
3759 * @pdev: PCI device whose resources were previously reserved
3760 * @bars: Bitmask of BARs to be released
3761 *
3762 * Release selected PCI I/O and memory resources previously reserved.
3763 * Call this function only after all use of the PCI regions has ceased.
3764 */
3765void pci_release_selected_regions(struct pci_dev *pdev, int bars)
3766{
3767	int i;
3768
3769	for (i = 0; i < 6; i++)
3770		if (bars & (1 << i))
3771			pci_release_region(pdev, i);
3772}
3773EXPORT_SYMBOL(pci_release_selected_regions);
3774
3775static int __pci_request_selected_regions(struct pci_dev *pdev, int bars,
3776					  const char *res_name, int excl)
3777{
3778	int i;
3779
3780	for (i = 0; i < 6; i++)
3781		if (bars & (1 << i))
3782			if (__pci_request_region(pdev, i, res_name, excl))
3783				goto err_out;
3784	return 0;
3785
3786err_out:
3787	while (--i >= 0)
3788		if (bars & (1 << i))
3789			pci_release_region(pdev, i);
3790
3791	return -EBUSY;
3792}
3793
3794
3795/**
3796 * pci_request_selected_regions - Reserve selected PCI I/O and memory resources
3797 * @pdev: PCI device whose resources are to be reserved
3798 * @bars: Bitmask of BARs to be requested
3799 * @res_name: Name to be associated with resource
3800 */
3801int pci_request_selected_regions(struct pci_dev *pdev, int bars,
3802				 const char *res_name)
3803{
3804	return __pci_request_selected_regions(pdev, bars, res_name, 0);
3805}
3806EXPORT_SYMBOL(pci_request_selected_regions);
3807
3808int pci_request_selected_regions_exclusive(struct pci_dev *pdev, int bars,
3809					   const char *res_name)
3810{
3811	return __pci_request_selected_regions(pdev, bars, res_name,
3812			IORESOURCE_EXCLUSIVE);
3813}
3814EXPORT_SYMBOL(pci_request_selected_regions_exclusive);
3815
3816/**
3817 * pci_release_regions - Release reserved PCI I/O and memory resources
3818 * @pdev: PCI device whose resources were previously reserved by
3819 *	  pci_request_regions()
3820 *
3821 * Releases all PCI I/O and memory resources previously reserved by a
3822 * successful call to pci_request_regions().  Call this function only
3823 * after all use of the PCI regions has ceased.
3824 */
3825
3826void pci_release_regions(struct pci_dev *pdev)
3827{
3828	pci_release_selected_regions(pdev, (1 << 6) - 1);
3829}
3830EXPORT_SYMBOL(pci_release_regions);
3831
3832/**
3833 * pci_request_regions - Reserve PCI I/O and memory resources
3834 * @pdev: PCI device whose resources are to be reserved
3835 * @res_name: Name to be associated with resource.
 
 
 
 
 
3836 *
3837 * Mark all PCI regions associated with PCI device @pdev as
3838 * being reserved by owner @res_name.  Do not access any
3839 * address inside the PCI regions unless this call returns
3840 * successfully.
3841 *
3842 * Returns 0 on success, or %EBUSY on error.  A warning
3843 * message is also printed on failure.
3844 */
3845int pci_request_regions(struct pci_dev *pdev, const char *res_name)
3846{
3847	return pci_request_selected_regions(pdev, ((1 << 6) - 1), res_name);
3848}
3849EXPORT_SYMBOL(pci_request_regions);
3850
3851/**
3852 * pci_request_regions_exclusive - Reserve PCI I/O and memory resources
3853 * @pdev: PCI device whose resources are to be reserved
3854 * @res_name: Name to be associated with resource.
 
 
 
 
 
3855 *
3856 * Mark all PCI regions associated with PCI device @pdev as being reserved
3857 * by owner @res_name.  Do not access any address inside the PCI regions
3858 * unless this call returns successfully.
3859 *
3860 * pci_request_regions_exclusive() will mark the region so that /dev/mem
3861 * and the sysfs MMIO access will not be allowed.
3862 *
3863 * Returns 0 on success, or %EBUSY on error.  A warning message is also
3864 * printed on failure.
3865 */
3866int pci_request_regions_exclusive(struct pci_dev *pdev, const char *res_name)
3867{
3868	return pci_request_selected_regions_exclusive(pdev,
3869					((1 << 6) - 1), res_name);
3870}
3871EXPORT_SYMBOL(pci_request_regions_exclusive);
3872
3873/*
3874 * Record the PCI IO range (expressed as CPU physical address + size).
3875 * Return a negative value if an error has occurred, zero otherwise
3876 */
3877int pci_register_io_range(struct fwnode_handle *fwnode, phys_addr_t addr,
3878			resource_size_t	size)
3879{
3880	int ret = 0;
3881#ifdef PCI_IOBASE
3882	struct logic_pio_hwaddr *range;
3883
3884	if (!size || addr + size < addr)
3885		return -EINVAL;
3886
3887	range = kzalloc(sizeof(*range), GFP_ATOMIC);
3888	if (!range)
3889		return -ENOMEM;
3890
3891	range->fwnode = fwnode;
3892	range->size = size;
3893	range->hw_start = addr;
3894	range->flags = LOGIC_PIO_CPU_MMIO;
3895
3896	ret = logic_pio_register_range(range);
3897	if (ret)
3898		kfree(range);
3899#endif
3900
3901	return ret;
3902}
3903
3904phys_addr_t pci_pio_to_address(unsigned long pio)
3905{
3906	phys_addr_t address = (phys_addr_t)OF_BAD_ADDR;
3907
3908#ifdef PCI_IOBASE
3909	if (pio >= MMIO_UPPER_LIMIT)
3910		return address;
3911
3912	address = logic_pio_to_hwaddr(pio);
3913#endif
3914
3915	return address;
3916}
3917
3918unsigned long __weak pci_address_to_pio(phys_addr_t address)
3919{
3920#ifdef PCI_IOBASE
3921	return logic_pio_trans_cpuaddr(address);
3922#else
3923	if (address > IO_SPACE_LIMIT)
3924		return (unsigned long)-1;
3925
3926	return (unsigned long) address;
3927#endif
3928}
3929
3930/**
3931 * pci_remap_iospace - Remap the memory mapped I/O space
3932 * @res: Resource describing the I/O space
3933 * @phys_addr: physical address of range to be mapped
3934 *
3935 * Remap the memory mapped I/O space described by the @res and the CPU
3936 * physical address @phys_addr into virtual address space.  Only
3937 * architectures that have memory mapped IO functions defined (and the
3938 * PCI_IOBASE value defined) should call this function.
3939 */
3940int pci_remap_iospace(const struct resource *res, phys_addr_t phys_addr)
3941{
3942#if defined(PCI_IOBASE) && defined(CONFIG_MMU)
3943	unsigned long vaddr = (unsigned long)PCI_IOBASE + res->start;
3944
3945	if (!(res->flags & IORESOURCE_IO))
3946		return -EINVAL;
3947
3948	if (res->end > IO_SPACE_LIMIT)
3949		return -EINVAL;
3950
3951	return ioremap_page_range(vaddr, vaddr + resource_size(res), phys_addr,
3952				  pgprot_device(PAGE_KERNEL));
3953#else
3954	/*
3955	 * This architecture does not have memory mapped I/O space,
3956	 * so this function should never be called
3957	 */
3958	WARN_ONCE(1, "This architecture does not support memory mapped I/O\n");
3959	return -ENODEV;
3960#endif
3961}
3962EXPORT_SYMBOL(pci_remap_iospace);
3963
3964/**
3965 * pci_unmap_iospace - Unmap the memory mapped I/O space
3966 * @res: resource to be unmapped
3967 *
3968 * Unmap the CPU virtual address @res from virtual address space.  Only
3969 * architectures that have memory mapped IO functions defined (and the
3970 * PCI_IOBASE value defined) should call this function.
3971 */
3972void pci_unmap_iospace(struct resource *res)
3973{
3974#if defined(PCI_IOBASE) && defined(CONFIG_MMU)
3975	unsigned long vaddr = (unsigned long)PCI_IOBASE + res->start;
3976
3977	unmap_kernel_range(vaddr, resource_size(res));
3978#endif
3979}
3980EXPORT_SYMBOL(pci_unmap_iospace);
3981
3982static void devm_pci_unmap_iospace(struct device *dev, void *ptr)
3983{
3984	struct resource **res = ptr;
3985
3986	pci_unmap_iospace(*res);
3987}
3988
3989/**
3990 * devm_pci_remap_iospace - Managed pci_remap_iospace()
3991 * @dev: Generic device to remap IO address for
3992 * @res: Resource describing the I/O space
3993 * @phys_addr: physical address of range to be mapped
3994 *
3995 * Managed pci_remap_iospace().  Map is automatically unmapped on driver
3996 * detach.
3997 */
3998int devm_pci_remap_iospace(struct device *dev, const struct resource *res,
3999			   phys_addr_t phys_addr)
4000{
4001	const struct resource **ptr;
4002	int error;
4003
4004	ptr = devres_alloc(devm_pci_unmap_iospace, sizeof(*ptr), GFP_KERNEL);
4005	if (!ptr)
4006		return -ENOMEM;
4007
4008	error = pci_remap_iospace(res, phys_addr);
4009	if (error) {
4010		devres_free(ptr);
4011	} else	{
4012		*ptr = res;
4013		devres_add(dev, ptr);
4014	}
4015
4016	return error;
4017}
4018EXPORT_SYMBOL(devm_pci_remap_iospace);
4019
4020/**
4021 * devm_pci_remap_cfgspace - Managed pci_remap_cfgspace()
4022 * @dev: Generic device to remap IO address for
4023 * @offset: Resource address to map
4024 * @size: Size of map
4025 *
4026 * Managed pci_remap_cfgspace().  Map is automatically unmapped on driver
4027 * detach.
4028 */
4029void __iomem *devm_pci_remap_cfgspace(struct device *dev,
4030				      resource_size_t offset,
4031				      resource_size_t size)
4032{
4033	void __iomem **ptr, *addr;
4034
4035	ptr = devres_alloc(devm_ioremap_release, sizeof(*ptr), GFP_KERNEL);
4036	if (!ptr)
4037		return NULL;
4038
4039	addr = pci_remap_cfgspace(offset, size);
4040	if (addr) {
4041		*ptr = addr;
4042		devres_add(dev, ptr);
4043	} else
4044		devres_free(ptr);
4045
4046	return addr;
4047}
4048EXPORT_SYMBOL(devm_pci_remap_cfgspace);
4049
4050/**
4051 * devm_pci_remap_cfg_resource - check, request region and ioremap cfg resource
4052 * @dev: generic device to handle the resource for
4053 * @res: configuration space resource to be handled
4054 *
4055 * Checks that a resource is a valid memory region, requests the memory
4056 * region and ioremaps with pci_remap_cfgspace() API that ensures the
4057 * proper PCI configuration space memory attributes are guaranteed.
4058 *
4059 * All operations are managed and will be undone on driver detach.
4060 *
4061 * Returns a pointer to the remapped memory or an ERR_PTR() encoded error code
4062 * on failure. Usage example::
4063 *
4064 *	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
4065 *	base = devm_pci_remap_cfg_resource(&pdev->dev, res);
4066 *	if (IS_ERR(base))
4067 *		return PTR_ERR(base);
4068 */
4069void __iomem *devm_pci_remap_cfg_resource(struct device *dev,
4070					  struct resource *res)
4071{
4072	resource_size_t size;
4073	const char *name;
4074	void __iomem *dest_ptr;
4075
4076	BUG_ON(!dev);
4077
4078	if (!res || resource_type(res) != IORESOURCE_MEM) {
4079		dev_err(dev, "invalid resource\n");
4080		return IOMEM_ERR_PTR(-EINVAL);
4081	}
4082
4083	size = resource_size(res);
4084	name = res->name ?: dev_name(dev);
4085
4086	if (!devm_request_mem_region(dev, res->start, size, name)) {
4087		dev_err(dev, "can't request region for resource %pR\n", res);
4088		return IOMEM_ERR_PTR(-EBUSY);
4089	}
4090
4091	dest_ptr = devm_pci_remap_cfgspace(dev, res->start, size);
4092	if (!dest_ptr) {
4093		dev_err(dev, "ioremap failed for resource %pR\n", res);
4094		devm_release_mem_region(dev, res->start, size);
4095		dest_ptr = IOMEM_ERR_PTR(-ENOMEM);
4096	}
4097
4098	return dest_ptr;
4099}
4100EXPORT_SYMBOL(devm_pci_remap_cfg_resource);
4101
4102static void __pci_set_master(struct pci_dev *dev, bool enable)
4103{
4104	u16 old_cmd, cmd;
4105
4106	pci_read_config_word(dev, PCI_COMMAND, &old_cmd);
4107	if (enable)
4108		cmd = old_cmd | PCI_COMMAND_MASTER;
4109	else
4110		cmd = old_cmd & ~PCI_COMMAND_MASTER;
4111	if (cmd != old_cmd) {
4112		pci_dbg(dev, "%s bus mastering\n",
4113			enable ? "enabling" : "disabling");
4114		pci_write_config_word(dev, PCI_COMMAND, cmd);
4115	}
4116	dev->is_busmaster = enable;
4117}
4118
4119/**
4120 * pcibios_setup - process "pci=" kernel boot arguments
4121 * @str: string used to pass in "pci=" kernel boot arguments
4122 *
4123 * Process kernel boot arguments.  This is the default implementation.
4124 * Architecture specific implementations can override this as necessary.
4125 */
4126char * __weak __init pcibios_setup(char *str)
4127{
4128	return str;
4129}
4130
4131/**
4132 * pcibios_set_master - enable PCI bus-mastering for device dev
4133 * @dev: the PCI device to enable
4134 *
4135 * Enables PCI bus-mastering for the device.  This is the default
4136 * implementation.  Architecture specific implementations can override
4137 * this if necessary.
4138 */
4139void __weak pcibios_set_master(struct pci_dev *dev)
4140{
4141	u8 lat;
4142
4143	/* The latency timer doesn't apply to PCIe (either Type 0 or Type 1) */
4144	if (pci_is_pcie(dev))
4145		return;
4146
4147	pci_read_config_byte(dev, PCI_LATENCY_TIMER, &lat);
4148	if (lat < 16)
4149		lat = (64 <= pcibios_max_latency) ? 64 : pcibios_max_latency;
4150	else if (lat > pcibios_max_latency)
4151		lat = pcibios_max_latency;
4152	else
4153		return;
4154
4155	pci_write_config_byte(dev, PCI_LATENCY_TIMER, lat);
4156}
4157
4158/**
4159 * pci_set_master - enables bus-mastering for device dev
4160 * @dev: the PCI device to enable
4161 *
4162 * Enables bus-mastering on the device and calls pcibios_set_master()
4163 * to do the needed arch specific settings.
4164 */
4165void pci_set_master(struct pci_dev *dev)
4166{
4167	__pci_set_master(dev, true);
4168	pcibios_set_master(dev);
4169}
4170EXPORT_SYMBOL(pci_set_master);
4171
4172/**
4173 * pci_clear_master - disables bus-mastering for device dev
4174 * @dev: the PCI device to disable
4175 */
4176void pci_clear_master(struct pci_dev *dev)
4177{
4178	__pci_set_master(dev, false);
4179}
4180EXPORT_SYMBOL(pci_clear_master);
4181
4182/**
4183 * pci_set_cacheline_size - ensure the CACHE_LINE_SIZE register is programmed
4184 * @dev: the PCI device for which MWI is to be enabled
4185 *
4186 * Helper function for pci_set_mwi.
4187 * Originally copied from drivers/net/acenic.c.
4188 * Copyright 1998-2001 by Jes Sorensen, <jes@trained-monkey.org>.
4189 *
4190 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
4191 */
4192int pci_set_cacheline_size(struct pci_dev *dev)
4193{
4194	u8 cacheline_size;
4195
4196	if (!pci_cache_line_size)
4197		return -EINVAL;
4198
4199	/* Validate current setting: the PCI_CACHE_LINE_SIZE must be
4200	   equal to or multiple of the right value. */
4201	pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
4202	if (cacheline_size >= pci_cache_line_size &&
4203	    (cacheline_size % pci_cache_line_size) == 0)
4204		return 0;
4205
4206	/* Write the correct value. */
4207	pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, pci_cache_line_size);
4208	/* Read it back. */
4209	pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
4210	if (cacheline_size == pci_cache_line_size)
4211		return 0;
4212
4213	pci_info(dev, "cache line size of %d is not supported\n",
4214		   pci_cache_line_size << 2);
4215
4216	return -EINVAL;
4217}
4218EXPORT_SYMBOL_GPL(pci_set_cacheline_size);
4219
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4220/**
4221 * pci_set_mwi - enables memory-write-invalidate PCI transaction
4222 * @dev: the PCI device for which MWI is enabled
4223 *
4224 * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND.
4225 *
4226 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
4227 */
4228int pci_set_mwi(struct pci_dev *dev)
 
4229{
4230#ifdef PCI_DISABLE_MWI
4231	return 0;
4232#else
4233	int rc;
4234	u16 cmd;
4235
4236	rc = pci_set_cacheline_size(dev);
4237	if (rc)
4238		return rc;
4239
4240	pci_read_config_word(dev, PCI_COMMAND, &cmd);
4241	if (!(cmd & PCI_COMMAND_INVALIDATE)) {
4242		pci_dbg(dev, "enabling Mem-Wr-Inval\n");
4243		cmd |= PCI_COMMAND_INVALIDATE;
4244		pci_write_config_word(dev, PCI_COMMAND, cmd);
4245	}
4246	return 0;
4247#endif
4248}
4249EXPORT_SYMBOL(pci_set_mwi);
4250
4251/**
4252 * pcim_set_mwi - a device-managed pci_set_mwi()
4253 * @dev: the PCI device for which MWI is enabled
4254 *
4255 * Managed pci_set_mwi().
4256 *
4257 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
4258 */
4259int pcim_set_mwi(struct pci_dev *dev)
4260{
4261	struct pci_devres *dr;
4262
4263	dr = find_pci_dr(dev);
4264	if (!dr)
4265		return -ENOMEM;
4266
4267	dr->mwi = 1;
4268	return pci_set_mwi(dev);
4269}
4270EXPORT_SYMBOL(pcim_set_mwi);
4271
4272/**
4273 * pci_try_set_mwi - enables memory-write-invalidate PCI transaction
4274 * @dev: the PCI device for which MWI is enabled
4275 *
4276 * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND.
4277 * Callers are not required to check the return value.
4278 *
4279 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
4280 */
4281int pci_try_set_mwi(struct pci_dev *dev)
4282{
4283#ifdef PCI_DISABLE_MWI
4284	return 0;
4285#else
4286	return pci_set_mwi(dev);
4287#endif
4288}
4289EXPORT_SYMBOL(pci_try_set_mwi);
4290
4291/**
4292 * pci_clear_mwi - disables Memory-Write-Invalidate for device dev
4293 * @dev: the PCI device to disable
4294 *
4295 * Disables PCI Memory-Write-Invalidate transaction on the device
4296 */
4297void pci_clear_mwi(struct pci_dev *dev)
 
4298{
4299#ifndef PCI_DISABLE_MWI
4300	u16 cmd;
4301
4302	pci_read_config_word(dev, PCI_COMMAND, &cmd);
4303	if (cmd & PCI_COMMAND_INVALIDATE) {
4304		cmd &= ~PCI_COMMAND_INVALIDATE;
4305		pci_write_config_word(dev, PCI_COMMAND, cmd);
4306	}
4307#endif
4308}
4309EXPORT_SYMBOL(pci_clear_mwi);
4310
4311/**
4312 * pci_intx - enables/disables PCI INTx for device dev
4313 * @pdev: the PCI device to operate on
4314 * @enable: boolean: whether to enable or disable PCI INTx
4315 *
4316 * Enables/disables PCI INTx for device @pdev
4317 */
4318void pci_intx(struct pci_dev *pdev, int enable)
 
4319{
4320	u16 pci_command, new;
4321
4322	pci_read_config_word(pdev, PCI_COMMAND, &pci_command);
4323
4324	if (enable)
4325		new = pci_command & ~PCI_COMMAND_INTX_DISABLE;
4326	else
4327		new = pci_command | PCI_COMMAND_INTX_DISABLE;
 
4328
4329	if (new != pci_command) {
4330		struct pci_devres *dr;
4331
4332		pci_write_config_word(pdev, PCI_COMMAND, new);
4333
4334		dr = find_pci_dr(pdev);
4335		if (dr && !dr->restore_intx) {
4336			dr->restore_intx = 1;
4337			dr->orig_intx = !enable;
4338		}
4339	}
4340}
4341EXPORT_SYMBOL_GPL(pci_intx);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4342
4343static bool pci_check_and_set_intx_mask(struct pci_dev *dev, bool mask)
4344{
4345	struct pci_bus *bus = dev->bus;
4346	bool mask_updated = true;
4347	u32 cmd_status_dword;
4348	u16 origcmd, newcmd;
4349	unsigned long flags;
4350	bool irq_pending;
4351
4352	/*
4353	 * We do a single dword read to retrieve both command and status.
4354	 * Document assumptions that make this possible.
4355	 */
4356	BUILD_BUG_ON(PCI_COMMAND % 4);
4357	BUILD_BUG_ON(PCI_COMMAND + 2 != PCI_STATUS);
4358
4359	raw_spin_lock_irqsave(&pci_lock, flags);
4360
4361	bus->ops->read(bus, dev->devfn, PCI_COMMAND, 4, &cmd_status_dword);
4362
4363	irq_pending = (cmd_status_dword >> 16) & PCI_STATUS_INTERRUPT;
4364
4365	/*
4366	 * Check interrupt status register to see whether our device
4367	 * triggered the interrupt (when masking) or the next IRQ is
4368	 * already pending (when unmasking).
4369	 */
4370	if (mask != irq_pending) {
4371		mask_updated = false;
4372		goto done;
4373	}
4374
4375	origcmd = cmd_status_dword;
4376	newcmd = origcmd & ~PCI_COMMAND_INTX_DISABLE;
4377	if (mask)
4378		newcmd |= PCI_COMMAND_INTX_DISABLE;
4379	if (newcmd != origcmd)
4380		bus->ops->write(bus, dev->devfn, PCI_COMMAND, 2, newcmd);
4381
4382done:
4383	raw_spin_unlock_irqrestore(&pci_lock, flags);
4384
4385	return mask_updated;
4386}
4387
4388/**
4389 * pci_check_and_mask_intx - mask INTx on pending interrupt
4390 * @dev: the PCI device to operate on
4391 *
4392 * Check if the device dev has its INTx line asserted, mask it and return
4393 * true in that case. False is returned if no interrupt was pending.
 
4394 */
4395bool pci_check_and_mask_intx(struct pci_dev *dev)
4396{
4397	return pci_check_and_set_intx_mask(dev, true);
4398}
4399EXPORT_SYMBOL_GPL(pci_check_and_mask_intx);
4400
4401/**
4402 * pci_check_and_unmask_intx - unmask INTx if no interrupt is pending
4403 * @dev: the PCI device to operate on
4404 *
4405 * Check if the device dev has its INTx line asserted, unmask it if not and
4406 * return true. False is returned and the mask remains active if there was
4407 * still an interrupt pending.
4408 */
4409bool pci_check_and_unmask_intx(struct pci_dev *dev)
4410{
4411	return pci_check_and_set_intx_mask(dev, false);
4412}
4413EXPORT_SYMBOL_GPL(pci_check_and_unmask_intx);
4414
4415/**
4416 * pci_wait_for_pending_transaction - wait for pending transaction
4417 * @dev: the PCI device to operate on
4418 *
4419 * Return 0 if transaction is pending 1 otherwise.
 
 
4420 */
4421int pci_wait_for_pending_transaction(struct pci_dev *dev)
4422{
4423	if (!pci_is_pcie(dev))
4424		return 1;
4425
4426	return pci_wait_for_pending(dev, pci_pcie_cap(dev) + PCI_EXP_DEVSTA,
4427				    PCI_EXP_DEVSTA_TRPND);
4428}
4429EXPORT_SYMBOL(pci_wait_for_pending_transaction);
4430
4431static int pci_dev_wait(struct pci_dev *dev, char *reset_type, int timeout)
4432{
4433	int delay = 1;
4434	u32 id;
4435
4436	/*
4437	 * After reset, the device should not silently discard config
4438	 * requests, but it may still indicate that it needs more time by
4439	 * responding to them with CRS completions.  The Root Port will
4440	 * generally synthesize ~0 data to complete the read (except when
4441	 * CRS SV is enabled and the read was for the Vendor ID; in that
4442	 * case it synthesizes 0x0001 data).
4443	 *
4444	 * Wait for the device to return a non-CRS completion.  Read the
4445	 * Command register instead of Vendor ID so we don't have to
4446	 * contend with the CRS SV value.
4447	 */
4448	pci_read_config_dword(dev, PCI_COMMAND, &id);
4449	while (id == ~0) {
4450		if (delay > timeout) {
4451			pci_warn(dev, "not ready %dms after %s; giving up\n",
4452				 delay - 1, reset_type);
4453			return -ENOTTY;
4454		}
4455
4456		if (delay > 1000)
4457			pci_info(dev, "not ready %dms after %s; waiting\n",
4458				 delay - 1, reset_type);
4459
4460		msleep(delay);
4461		delay *= 2;
4462		pci_read_config_dword(dev, PCI_COMMAND, &id);
4463	}
 
 
4464
4465	if (delay > 1000)
4466		pci_info(dev, "ready %dms after %s\n", delay - 1,
4467			 reset_type);
 
 
4468
4469	return 0;
 
 
4470}
 
4471
4472/**
4473 * pcie_has_flr - check if a device supports function level resets
4474 * @dev: device to check
4475 *
4476 * Returns true if the device advertises support for PCIe function level
4477 * resets.
4478 */
4479bool pcie_has_flr(struct pci_dev *dev)
4480{
4481	u32 cap;
4482
4483	if (dev->dev_flags & PCI_DEV_FLAGS_NO_FLR_RESET)
4484		return false;
4485
4486	pcie_capability_read_dword(dev, PCI_EXP_DEVCAP, &cap);
4487	return cap & PCI_EXP_DEVCAP_FLR;
4488}
4489EXPORT_SYMBOL_GPL(pcie_has_flr);
4490
4491/**
4492 * pcie_flr - initiate a PCIe function level reset
4493 * @dev: device to reset
4494 *
4495 * Initiate a function level reset on @dev.  The caller should ensure the
4496 * device supports FLR before calling this function, e.g. by using the
4497 * pcie_has_flr() helper.
4498 */
4499int pcie_flr(struct pci_dev *dev)
4500{
4501	if (!pci_wait_for_pending_transaction(dev))
4502		pci_err(dev, "timed out waiting for pending transaction; performing function level reset anyway\n");
4503
4504	pcie_capability_set_word(dev, PCI_EXP_DEVCTL, PCI_EXP_DEVCTL_BCR_FLR);
 
 
4505
4506	if (dev->imm_ready)
4507		return 0;
4508
4509	/*
4510	 * Per PCIe r4.0, sec 6.6.2, a device must complete an FLR within
4511	 * 100ms, but may silently discard requests while the FLR is in
4512	 * progress.  Wait 100ms before trying to access the device.
4513	 */
4514	msleep(100);
4515
4516	return pci_dev_wait(dev, "FLR", PCIE_RESET_READY_POLL_MS);
4517}
4518EXPORT_SYMBOL_GPL(pcie_flr);
4519
4520static int pci_af_flr(struct pci_dev *dev, int probe)
4521{
4522	int pos;
4523	u8 cap;
4524
4525	pos = pci_find_capability(dev, PCI_CAP_ID_AF);
4526	if (!pos)
4527		return -ENOTTY;
4528
4529	if (dev->dev_flags & PCI_DEV_FLAGS_NO_FLR_RESET)
4530		return -ENOTTY;
4531
4532	pci_read_config_byte(dev, pos + PCI_AF_CAP, &cap);
4533	if (!(cap & PCI_AF_CAP_TP) || !(cap & PCI_AF_CAP_FLR))
4534		return -ENOTTY;
4535
4536	if (probe)
4537		return 0;
4538
4539	/*
4540	 * Wait for Transaction Pending bit to clear.  A word-aligned test
4541	 * is used, so we use the control offset rather than status and shift
4542	 * the test bit to match.
4543	 */
4544	if (!pci_wait_for_pending(dev, pos + PCI_AF_CTRL,
4545				 PCI_AF_STATUS_TP << 8))
4546		pci_err(dev, "timed out waiting for pending transaction; performing AF function level reset anyway\n");
4547
4548	pci_write_config_byte(dev, pos + PCI_AF_CTRL, PCI_AF_CTRL_FLR);
4549
4550	if (dev->imm_ready)
4551		return 0;
4552
4553	/*
4554	 * Per Advanced Capabilities for Conventional PCI ECN, 13 April 2006,
4555	 * updated 27 July 2006; a device must complete an FLR within
4556	 * 100ms, but may silently discard requests while the FLR is in
4557	 * progress.  Wait 100ms before trying to access the device.
4558	 */
4559	msleep(100);
4560
4561	return pci_dev_wait(dev, "AF_FLR", PCIE_RESET_READY_POLL_MS);
4562}
4563
4564/**
4565 * pci_pm_reset - Put device into PCI_D3 and back into PCI_D0.
4566 * @dev: Device to reset.
4567 * @probe: If set, only check if the device can be reset this way.
4568 *
4569 * If @dev supports native PCI PM and its PCI_PM_CTRL_NO_SOFT_RESET flag is
4570 * unset, it will be reinitialized internally when going from PCI_D3hot to
4571 * PCI_D0.  If that's the case and the device is not in a low-power state
4572 * already, force it into PCI_D3hot and back to PCI_D0, causing it to be reset.
4573 *
4574 * NOTE: This causes the caller to sleep for twice the device power transition
4575 * cooldown period, which for the D0->D3hot and D3hot->D0 transitions is 10 ms
4576 * by default (i.e. unless the @dev's d3_delay field has a different value).
4577 * Moreover, only devices in D0 can be reset by this function.
4578 */
4579static int pci_pm_reset(struct pci_dev *dev, int probe)
4580{
4581	u16 csr;
4582
4583	if (!dev->pm_cap || dev->dev_flags & PCI_DEV_FLAGS_NO_PM_RESET)
4584		return -ENOTTY;
4585
4586	pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &csr);
4587	if (csr & PCI_PM_CTRL_NO_SOFT_RESET)
4588		return -ENOTTY;
4589
4590	if (probe)
4591		return 0;
4592
4593	if (dev->current_state != PCI_D0)
4594		return -EINVAL;
4595
4596	csr &= ~PCI_PM_CTRL_STATE_MASK;
4597	csr |= PCI_D3hot;
4598	pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, csr);
4599	pci_dev_d3_sleep(dev);
4600
4601	csr &= ~PCI_PM_CTRL_STATE_MASK;
4602	csr |= PCI_D0;
4603	pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, csr);
4604	pci_dev_d3_sleep(dev);
4605
4606	return pci_dev_wait(dev, "PM D3->D0", PCIE_RESET_READY_POLL_MS);
4607}
 
4608/**
4609 * pcie_wait_for_link - Wait until link is active or inactive
4610 * @pdev: Bridge device
4611 * @active: waiting for active or inactive?
4612 *
4613 * Use this to wait till link becomes active or inactive.
 
4614 */
4615bool pcie_wait_for_link(struct pci_dev *pdev, bool active)
4616{
4617	int timeout = 1000;
4618	bool ret;
4619	u16 lnk_status;
4620
4621	/*
4622	 * Some controllers might not implement link active reporting. In this
4623	 * case, we wait for 1000 + 100 ms.
4624	 */
4625	if (!pdev->link_active_reporting) {
4626		msleep(1100);
4627		return true;
4628	}
4629
4630	/*
4631	 * PCIe r4.0 sec 6.6.1, a component must enter LTSSM Detect within 20ms,
4632	 * after which we should expect an link active if the reset was
4633	 * successful. If so, software must wait a minimum 100ms before sending
4634	 * configuration requests to devices downstream this port.
4635	 *
4636	 * If the link fails to activate, either the device was physically
4637	 * removed or the link is permanently failed.
4638	 */
4639	if (active)
4640		msleep(20);
4641	for (;;) {
4642		pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &lnk_status);
4643		ret = !!(lnk_status & PCI_EXP_LNKSTA_DLLLA);
4644		if (ret == active)
4645			break;
4646		if (timeout <= 0)
4647			break;
4648		msleep(10);
4649		timeout -= 10;
4650	}
4651	if (active && ret)
4652		msleep(100);
4653	else if (ret != active)
4654		pci_info(pdev, "Data Link Layer Link Active not %s in 1000 msec\n",
4655			active ? "set" : "cleared");
4656	return ret == active;
4657}
4658
4659void pci_reset_secondary_bus(struct pci_dev *dev)
4660{
4661	u16 ctrl;
4662
4663	pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &ctrl);
4664	ctrl |= PCI_BRIDGE_CTL_BUS_RESET;
4665	pci_write_config_word(dev, PCI_BRIDGE_CONTROL, ctrl);
4666
4667	/*
4668	 * PCI spec v3.0 7.6.4.2 requires minimum Trst of 1ms.  Double
4669	 * this to 2ms to ensure that we meet the minimum requirement.
4670	 */
4671	msleep(2);
4672
4673	ctrl &= ~PCI_BRIDGE_CTL_BUS_RESET;
4674	pci_write_config_word(dev, PCI_BRIDGE_CONTROL, ctrl);
4675
4676	/*
4677	 * Trhfa for conventional PCI is 2^25 clock cycles.
4678	 * Assuming a minimum 33MHz clock this results in a 1s
4679	 * delay before we can consider subordinate devices to
4680	 * be re-initialized.  PCIe has some ways to shorten this,
4681	 * but we don't make use of them yet.
4682	 */
4683	ssleep(1);
4684}
4685
4686void __weak pcibios_reset_secondary_bus(struct pci_dev *dev)
4687{
4688	pci_reset_secondary_bus(dev);
4689}
4690
4691/**
4692 * pci_bridge_secondary_bus_reset - Reset the secondary bus on a PCI bridge.
4693 * @dev: Bridge device
4694 *
4695 * Use the bridge control register to assert reset on the secondary bus.
4696 * Devices on the secondary bus are left in power-on state.
4697 */
4698int pci_bridge_secondary_bus_reset(struct pci_dev *dev)
4699{
4700	pcibios_reset_secondary_bus(dev);
4701
4702	return pci_dev_wait(dev, "bus reset", PCIE_RESET_READY_POLL_MS);
4703}
4704EXPORT_SYMBOL_GPL(pci_bridge_secondary_bus_reset);
4705
4706static int pci_parent_bus_reset(struct pci_dev *dev, int probe)
4707{
4708	struct pci_dev *pdev;
4709
4710	if (pci_is_root_bus(dev->bus) || dev->subordinate ||
4711	    !dev->bus->self || dev->dev_flags & PCI_DEV_FLAGS_NO_BUS_RESET)
4712		return -ENOTTY;
4713
4714	list_for_each_entry(pdev, &dev->bus->devices, bus_list)
4715		if (pdev != dev)
4716			return -ENOTTY;
4717
4718	if (probe)
4719		return 0;
4720
4721	return pci_bridge_secondary_bus_reset(dev->bus->self);
 
 
4722}
4723
4724static int pci_reset_hotplug_slot(struct hotplug_slot *hotplug, int probe)
4725{
4726	int rc = -ENOTTY;
4727
4728	if (!hotplug || !try_module_get(hotplug->owner))
4729		return rc;
4730
4731	if (hotplug->ops->reset_slot)
4732		rc = hotplug->ops->reset_slot(hotplug, probe);
4733
4734	module_put(hotplug->owner);
4735
4736	return rc;
4737}
4738
4739static int pci_dev_reset_slot_function(struct pci_dev *dev, int probe)
4740{
4741	struct pci_dev *pdev;
4742
4743	if (dev->subordinate || !dev->slot ||
4744	    dev->dev_flags & PCI_DEV_FLAGS_NO_BUS_RESET)
4745		return -ENOTTY;
4746
4747	list_for_each_entry(pdev, &dev->bus->devices, bus_list)
4748		if (pdev != dev && pdev->slot == dev->slot)
4749			return -ENOTTY;
4750
4751	return pci_reset_hotplug_slot(dev->slot->hotplug, probe);
4752}
4753
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4754static void pci_dev_lock(struct pci_dev *dev)
4755{
4756	pci_cfg_access_lock(dev);
4757	/* block PM suspend, driver probe, etc. */
4758	device_lock(&dev->dev);
4759}
4760
4761/* Return 1 on successful lock, 0 on contention */
4762static int pci_dev_trylock(struct pci_dev *dev)
4763{
4764	if (pci_cfg_access_trylock(dev)) {
4765		if (device_trylock(&dev->dev))
4766			return 1;
4767		pci_cfg_access_unlock(dev);
4768	}
4769
4770	return 0;
4771}
4772
4773static void pci_dev_unlock(struct pci_dev *dev)
4774{
4775	device_unlock(&dev->dev);
4776	pci_cfg_access_unlock(dev);
4777}
4778
4779static void pci_dev_save_and_disable(struct pci_dev *dev)
4780{
4781	const struct pci_error_handlers *err_handler =
4782			dev->driver ? dev->driver->err_handler : NULL;
4783
4784	/*
4785	 * dev->driver->err_handler->reset_prepare() is protected against
4786	 * races with ->remove() by the device lock, which must be held by
4787	 * the caller.
4788	 */
4789	if (err_handler && err_handler->reset_prepare)
4790		err_handler->reset_prepare(dev);
4791
4792	/*
4793	 * Wake-up device prior to save.  PM registers default to D0 after
4794	 * reset and a simple register restore doesn't reliably return
4795	 * to a non-D0 state anyway.
4796	 */
4797	pci_set_power_state(dev, PCI_D0);
4798
4799	pci_save_state(dev);
4800	/*
4801	 * Disable the device by clearing the Command register, except for
4802	 * INTx-disable which is set.  This not only disables MMIO and I/O port
4803	 * BARs, but also prevents the device from being Bus Master, preventing
4804	 * DMA from the device including MSI/MSI-X interrupts.  For PCI 2.3
4805	 * compliant devices, INTx-disable prevents legacy interrupts.
4806	 */
4807	pci_write_config_word(dev, PCI_COMMAND, PCI_COMMAND_INTX_DISABLE);
4808}
4809
4810static void pci_dev_restore(struct pci_dev *dev)
4811{
4812	const struct pci_error_handlers *err_handler =
4813			dev->driver ? dev->driver->err_handler : NULL;
4814
4815	pci_restore_state(dev);
 
4816
4817	/*
4818	 * dev->driver->err_handler->reset_done() is protected against
4819	 * races with ->remove() by the device lock, which must be held by
4820	 * the caller.
4821	 */
4822	if (err_handler && err_handler->reset_done)
4823		err_handler->reset_done(dev);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4824}
 
4825
4826/**
4827 * __pci_reset_function_locked - reset a PCI device function while holding
4828 * the @dev mutex lock.
4829 * @dev: PCI device to reset
4830 *
4831 * Some devices allow an individual function to be reset without affecting
4832 * other functions in the same device.  The PCI device must be responsive
4833 * to PCI config space in order to use this function.
4834 *
4835 * The device function is presumed to be unused and the caller is holding
4836 * the device mutex lock when this function is called.
4837 *
4838 * Resetting the device will make the contents of PCI configuration space
4839 * random, so any caller of this must be prepared to reinitialise the
4840 * device including MSI, bus mastering, BARs, decoding IO and memory spaces,
4841 * etc.
4842 *
4843 * Returns 0 if the device function was successfully reset or negative if the
4844 * device doesn't support resetting a single function.
4845 */
4846int __pci_reset_function_locked(struct pci_dev *dev)
4847{
4848	int rc;
4849
4850	might_sleep();
4851
4852	/*
4853	 * A reset method returns -ENOTTY if it doesn't support this device
4854	 * and we should try the next method.
4855	 *
4856	 * If it returns 0 (success), we're finished.  If it returns any
4857	 * other error, we're also finished: this indicates that further
4858	 * reset mechanisms might be broken on the device.
4859	 */
4860	rc = pci_dev_specific_reset(dev, 0);
4861	if (rc != -ENOTTY)
4862		return rc;
4863	if (pcie_has_flr(dev)) {
4864		rc = pcie_flr(dev);
4865		if (rc != -ENOTTY)
4866			return rc;
4867	}
4868	rc = pci_af_flr(dev, 0);
4869	if (rc != -ENOTTY)
4870		return rc;
4871	rc = pci_pm_reset(dev, 0);
4872	if (rc != -ENOTTY)
4873		return rc;
4874	rc = pci_dev_reset_slot_function(dev, 0);
4875	if (rc != -ENOTTY)
4876		return rc;
4877	return pci_parent_bus_reset(dev, 0);
4878}
4879EXPORT_SYMBOL_GPL(__pci_reset_function_locked);
4880
4881/**
4882 * pci_probe_reset_function - check whether the device can be safely reset
4883 * @dev: PCI device to reset
4884 *
4885 * Some devices allow an individual function to be reset without affecting
4886 * other functions in the same device.  The PCI device must be responsive
4887 * to PCI config space in order to use this function.
4888 *
4889 * Returns 0 if the device function can be reset or negative if the
4890 * device doesn't support resetting a single function.
4891 */
4892int pci_probe_reset_function(struct pci_dev *dev)
4893{
4894	int rc;
4895
4896	might_sleep();
4897
4898	rc = pci_dev_specific_reset(dev, 1);
4899	if (rc != -ENOTTY)
4900		return rc;
4901	if (pcie_has_flr(dev))
4902		return 0;
4903	rc = pci_af_flr(dev, 1);
4904	if (rc != -ENOTTY)
4905		return rc;
4906	rc = pci_pm_reset(dev, 1);
4907	if (rc != -ENOTTY)
4908		return rc;
4909	rc = pci_dev_reset_slot_function(dev, 1);
4910	if (rc != -ENOTTY)
4911		return rc;
4912
4913	return pci_parent_bus_reset(dev, 1);
4914}
4915
4916/**
4917 * pci_reset_function - quiesce and reset a PCI device function
4918 * @dev: PCI device to reset
4919 *
4920 * Some devices allow an individual function to be reset without affecting
4921 * other functions in the same device.  The PCI device must be responsive
4922 * to PCI config space in order to use this function.
4923 *
4924 * This function does not just reset the PCI portion of a device, but
4925 * clears all the state associated with the device.  This function differs
4926 * from __pci_reset_function_locked() in that it saves and restores device state
4927 * over the reset and takes the PCI device lock.
4928 *
4929 * Returns 0 if the device function was successfully reset or negative if the
4930 * device doesn't support resetting a single function.
4931 */
4932int pci_reset_function(struct pci_dev *dev)
4933{
4934	int rc;
4935
4936	if (!dev->reset_fn)
4937		return -ENOTTY;
 
4938
4939	pci_dev_lock(dev);
4940	pci_dev_save_and_disable(dev);
4941
4942	rc = __pci_reset_function_locked(dev);
4943
4944	pci_dev_restore(dev);
4945	pci_dev_unlock(dev);
4946
4947	return rc;
4948}
4949EXPORT_SYMBOL_GPL(pci_reset_function);
4950
4951/**
4952 * pci_reset_function_locked - quiesce and reset a PCI device function
4953 * @dev: PCI device to reset
4954 *
4955 * Some devices allow an individual function to be reset without affecting
4956 * other functions in the same device.  The PCI device must be responsive
4957 * to PCI config space in order to use this function.
4958 *
4959 * This function does not just reset the PCI portion of a device, but
4960 * clears all the state associated with the device.  This function differs
4961 * from __pci_reset_function_locked() in that it saves and restores device state
4962 * over the reset.  It also differs from pci_reset_function() in that it
4963 * requires the PCI device lock to be held.
4964 *
4965 * Returns 0 if the device function was successfully reset or negative if the
4966 * device doesn't support resetting a single function.
4967 */
4968int pci_reset_function_locked(struct pci_dev *dev)
4969{
4970	int rc;
4971
4972	if (!dev->reset_fn)
4973		return -ENOTTY;
4974
4975	pci_dev_save_and_disable(dev);
4976
4977	rc = __pci_reset_function_locked(dev);
4978
4979	pci_dev_restore(dev);
4980
4981	return rc;
4982}
4983EXPORT_SYMBOL_GPL(pci_reset_function_locked);
4984
4985/**
4986 * pci_try_reset_function - quiesce and reset a PCI device function
4987 * @dev: PCI device to reset
4988 *
4989 * Same as above, except return -EAGAIN if unable to lock device.
4990 */
4991int pci_try_reset_function(struct pci_dev *dev)
4992{
4993	int rc;
4994
4995	if (!dev->reset_fn)
4996		return -ENOTTY;
4997
4998	if (!pci_dev_trylock(dev))
4999		return -EAGAIN;
5000
5001	pci_dev_save_and_disable(dev);
5002	rc = __pci_reset_function_locked(dev);
 
 
 
 
 
 
5003	pci_dev_restore(dev);
5004	pci_dev_unlock(dev);
5005
5006	return rc;
5007}
5008EXPORT_SYMBOL_GPL(pci_try_reset_function);
5009
5010/* Do any devices on or below this bus prevent a bus reset? */
5011static bool pci_bus_resetable(struct pci_bus *bus)
5012{
5013	struct pci_dev *dev;
5014
5015
5016	if (bus->self && (bus->self->dev_flags & PCI_DEV_FLAGS_NO_BUS_RESET))
5017		return false;
5018
5019	list_for_each_entry(dev, &bus->devices, bus_list) {
5020		if (dev->dev_flags & PCI_DEV_FLAGS_NO_BUS_RESET ||
5021		    (dev->subordinate && !pci_bus_resetable(dev->subordinate)))
5022			return false;
5023	}
5024
5025	return true;
5026}
5027
5028/* Lock devices from the top of the tree down */
5029static void pci_bus_lock(struct pci_bus *bus)
5030{
5031	struct pci_dev *dev;
5032
5033	list_for_each_entry(dev, &bus->devices, bus_list) {
5034		pci_dev_lock(dev);
5035		if (dev->subordinate)
5036			pci_bus_lock(dev->subordinate);
5037	}
5038}
5039
5040/* Unlock devices from the bottom of the tree up */
5041static void pci_bus_unlock(struct pci_bus *bus)
5042{
5043	struct pci_dev *dev;
5044
5045	list_for_each_entry(dev, &bus->devices, bus_list) {
5046		if (dev->subordinate)
5047			pci_bus_unlock(dev->subordinate);
5048		pci_dev_unlock(dev);
5049	}
5050}
5051
5052/* Return 1 on successful lock, 0 on contention */
5053static int pci_bus_trylock(struct pci_bus *bus)
5054{
5055	struct pci_dev *dev;
5056
5057	list_for_each_entry(dev, &bus->devices, bus_list) {
5058		if (!pci_dev_trylock(dev))
5059			goto unlock;
5060		if (dev->subordinate) {
5061			if (!pci_bus_trylock(dev->subordinate)) {
5062				pci_dev_unlock(dev);
5063				goto unlock;
5064			}
5065		}
5066	}
5067	return 1;
5068
5069unlock:
5070	list_for_each_entry_continue_reverse(dev, &bus->devices, bus_list) {
5071		if (dev->subordinate)
5072			pci_bus_unlock(dev->subordinate);
5073		pci_dev_unlock(dev);
5074	}
5075	return 0;
5076}
5077
5078/* Do any devices on or below this slot prevent a bus reset? */
5079static bool pci_slot_resetable(struct pci_slot *slot)
5080{
5081	struct pci_dev *dev;
5082
5083	if (slot->bus->self &&
5084	    (slot->bus->self->dev_flags & PCI_DEV_FLAGS_NO_BUS_RESET))
5085		return false;
5086
5087	list_for_each_entry(dev, &slot->bus->devices, bus_list) {
5088		if (!dev->slot || dev->slot != slot)
5089			continue;
5090		if (dev->dev_flags & PCI_DEV_FLAGS_NO_BUS_RESET ||
5091		    (dev->subordinate && !pci_bus_resetable(dev->subordinate)))
5092			return false;
5093	}
5094
5095	return true;
5096}
5097
5098/* Lock devices from the top of the tree down */
5099static void pci_slot_lock(struct pci_slot *slot)
5100{
5101	struct pci_dev *dev;
5102
5103	list_for_each_entry(dev, &slot->bus->devices, bus_list) {
5104		if (!dev->slot || dev->slot != slot)
5105			continue;
5106		pci_dev_lock(dev);
5107		if (dev->subordinate)
5108			pci_bus_lock(dev->subordinate);
5109	}
5110}
5111
5112/* Unlock devices from the bottom of the tree up */
5113static void pci_slot_unlock(struct pci_slot *slot)
5114{
5115	struct pci_dev *dev;
5116
5117	list_for_each_entry(dev, &slot->bus->devices, bus_list) {
5118		if (!dev->slot || dev->slot != slot)
5119			continue;
5120		if (dev->subordinate)
5121			pci_bus_unlock(dev->subordinate);
5122		pci_dev_unlock(dev);
5123	}
5124}
5125
5126/* Return 1 on successful lock, 0 on contention */
5127static int pci_slot_trylock(struct pci_slot *slot)
5128{
5129	struct pci_dev *dev;
5130
5131	list_for_each_entry(dev, &slot->bus->devices, bus_list) {
5132		if (!dev->slot || dev->slot != slot)
5133			continue;
5134		if (!pci_dev_trylock(dev))
5135			goto unlock;
5136		if (dev->subordinate) {
5137			if (!pci_bus_trylock(dev->subordinate)) {
5138				pci_dev_unlock(dev);
5139				goto unlock;
5140			}
5141		}
5142	}
5143	return 1;
5144
5145unlock:
5146	list_for_each_entry_continue_reverse(dev,
5147					     &slot->bus->devices, bus_list) {
5148		if (!dev->slot || dev->slot != slot)
5149			continue;
5150		if (dev->subordinate)
5151			pci_bus_unlock(dev->subordinate);
5152		pci_dev_unlock(dev);
5153	}
5154	return 0;
5155}
5156
5157/*
5158 * Save and disable devices from the top of the tree down while holding
5159 * the @dev mutex lock for the entire tree.
5160 */
5161static void pci_bus_save_and_disable_locked(struct pci_bus *bus)
5162{
5163	struct pci_dev *dev;
5164
5165	list_for_each_entry(dev, &bus->devices, bus_list) {
5166		pci_dev_save_and_disable(dev);
5167		if (dev->subordinate)
5168			pci_bus_save_and_disable_locked(dev->subordinate);
5169	}
5170}
5171
5172/*
5173 * Restore devices from top of the tree down while holding @dev mutex lock
5174 * for the entire tree.  Parent bridges need to be restored before we can
5175 * get to subordinate devices.
5176 */
5177static void pci_bus_restore_locked(struct pci_bus *bus)
5178{
5179	struct pci_dev *dev;
5180
5181	list_for_each_entry(dev, &bus->devices, bus_list) {
5182		pci_dev_restore(dev);
5183		if (dev->subordinate)
5184			pci_bus_restore_locked(dev->subordinate);
5185	}
5186}
5187
5188/*
5189 * Save and disable devices from the top of the tree down while holding
5190 * the @dev mutex lock for the entire tree.
5191 */
5192static void pci_slot_save_and_disable_locked(struct pci_slot *slot)
5193{
5194	struct pci_dev *dev;
5195
5196	list_for_each_entry(dev, &slot->bus->devices, bus_list) {
5197		if (!dev->slot || dev->slot != slot)
5198			continue;
5199		pci_dev_save_and_disable(dev);
5200		if (dev->subordinate)
5201			pci_bus_save_and_disable_locked(dev->subordinate);
5202	}
5203}
5204
5205/*
5206 * Restore devices from top of the tree down while holding @dev mutex lock
5207 * for the entire tree.  Parent bridges need to be restored before we can
5208 * get to subordinate devices.
5209 */
5210static void pci_slot_restore_locked(struct pci_slot *slot)
5211{
5212	struct pci_dev *dev;
5213
5214	list_for_each_entry(dev, &slot->bus->devices, bus_list) {
5215		if (!dev->slot || dev->slot != slot)
5216			continue;
5217		pci_dev_restore(dev);
5218		if (dev->subordinate)
5219			pci_bus_restore_locked(dev->subordinate);
5220	}
5221}
5222
5223static int pci_slot_reset(struct pci_slot *slot, int probe)
5224{
5225	int rc;
5226
5227	if (!slot || !pci_slot_resetable(slot))
5228		return -ENOTTY;
5229
5230	if (!probe)
5231		pci_slot_lock(slot);
5232
5233	might_sleep();
5234
5235	rc = pci_reset_hotplug_slot(slot->hotplug, probe);
5236
5237	if (!probe)
5238		pci_slot_unlock(slot);
5239
5240	return rc;
5241}
5242
5243/**
5244 * pci_probe_reset_slot - probe whether a PCI slot can be reset
5245 * @slot: PCI slot to probe
5246 *
5247 * Return 0 if slot can be reset, negative if a slot reset is not supported.
5248 */
5249int pci_probe_reset_slot(struct pci_slot *slot)
5250{
5251	return pci_slot_reset(slot, 1);
5252}
5253EXPORT_SYMBOL_GPL(pci_probe_reset_slot);
5254
5255/**
5256 * __pci_reset_slot - Try to reset a PCI slot
5257 * @slot: PCI slot to reset
5258 *
5259 * A PCI bus may host multiple slots, each slot may support a reset mechanism
5260 * independent of other slots.  For instance, some slots may support slot power
5261 * control.  In the case of a 1:1 bus to slot architecture, this function may
5262 * wrap the bus reset to avoid spurious slot related events such as hotplug.
5263 * Generally a slot reset should be attempted before a bus reset.  All of the
5264 * function of the slot and any subordinate buses behind the slot are reset
5265 * through this function.  PCI config space of all devices in the slot and
5266 * behind the slot is saved before and restored after reset.
5267 *
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5268 * Same as above except return -EAGAIN if the slot cannot be locked
5269 */
5270static int __pci_reset_slot(struct pci_slot *slot)
5271{
5272	int rc;
5273
5274	rc = pci_slot_reset(slot, 1);
5275	if (rc)
5276		return rc;
5277
 
 
5278	if (pci_slot_trylock(slot)) {
5279		pci_slot_save_and_disable_locked(slot);
5280		might_sleep();
5281		rc = pci_reset_hotplug_slot(slot->hotplug, 0);
5282		pci_slot_restore_locked(slot);
5283		pci_slot_unlock(slot);
5284	} else
5285		rc = -EAGAIN;
5286
 
 
5287	return rc;
5288}
 
5289
5290static int pci_bus_reset(struct pci_bus *bus, int probe)
5291{
5292	int ret;
5293
5294	if (!bus->self || !pci_bus_resetable(bus))
5295		return -ENOTTY;
5296
5297	if (probe)
5298		return 0;
5299
5300	pci_bus_lock(bus);
5301
5302	might_sleep();
5303
5304	ret = pci_bridge_secondary_bus_reset(bus->self);
5305
5306	pci_bus_unlock(bus);
5307
5308	return ret;
5309}
5310
5311/**
5312 * pci_bus_error_reset - reset the bridge's subordinate bus
5313 * @bridge: The parent device that connects to the bus to reset
5314 *
5315 * This function will first try to reset the slots on this bus if the method is
5316 * available. If slot reset fails or is not available, this will fall back to a
5317 * secondary bus reset.
5318 */
5319int pci_bus_error_reset(struct pci_dev *bridge)
5320{
5321	struct pci_bus *bus = bridge->subordinate;
5322	struct pci_slot *slot;
5323
5324	if (!bus)
5325		return -ENOTTY;
5326
5327	mutex_lock(&pci_slot_mutex);
5328	if (list_empty(&bus->slots))
5329		goto bus_reset;
5330
5331	list_for_each_entry(slot, &bus->slots, list)
5332		if (pci_probe_reset_slot(slot))
5333			goto bus_reset;
5334
5335	list_for_each_entry(slot, &bus->slots, list)
5336		if (pci_slot_reset(slot, 0))
5337			goto bus_reset;
5338
5339	mutex_unlock(&pci_slot_mutex);
5340	return 0;
5341bus_reset:
5342	mutex_unlock(&pci_slot_mutex);
5343	return pci_bus_reset(bridge->subordinate, 0);
5344}
5345
5346/**
5347 * pci_probe_reset_bus - probe whether a PCI bus can be reset
5348 * @bus: PCI bus to probe
5349 *
5350 * Return 0 if bus can be reset, negative if a bus reset is not supported.
5351 */
5352int pci_probe_reset_bus(struct pci_bus *bus)
5353{
5354	return pci_bus_reset(bus, 1);
5355}
5356EXPORT_SYMBOL_GPL(pci_probe_reset_bus);
5357
5358/**
5359 * __pci_reset_bus - Try to reset a PCI bus
5360 * @bus: top level PCI bus to reset
5361 *
5362 * Same as above except return -EAGAIN if the bus cannot be locked
 
 
 
5363 */
5364static int __pci_reset_bus(struct pci_bus *bus)
5365{
5366	int rc;
5367
5368	rc = pci_bus_reset(bus, 1);
5369	if (rc)
5370		return rc;
5371
5372	if (pci_bus_trylock(bus)) {
5373		pci_bus_save_and_disable_locked(bus);
5374		might_sleep();
5375		rc = pci_bridge_secondary_bus_reset(bus->self);
5376		pci_bus_restore_locked(bus);
5377		pci_bus_unlock(bus);
5378	} else
5379		rc = -EAGAIN;
5380
5381	return rc;
5382}
 
5383
5384/**
5385 * pci_reset_bus - Try to reset a PCI bus
5386 * @pdev: top level PCI device to reset via slot/bus
5387 *
5388 * Same as above except return -EAGAIN if the bus cannot be locked
5389 */
5390int pci_reset_bus(struct pci_dev *pdev)
5391{
5392	return (!pci_probe_reset_slot(pdev->slot)) ?
5393	    __pci_reset_slot(pdev->slot) : __pci_reset_bus(pdev->bus);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5394}
5395EXPORT_SYMBOL_GPL(pci_reset_bus);
5396
5397/**
5398 * pcix_get_max_mmrbc - get PCI-X maximum designed memory read byte count
5399 * @dev: PCI device to query
5400 *
5401 * Returns mmrbc: maximum designed memory read count in bytes or
5402 * appropriate error value.
5403 */
5404int pcix_get_max_mmrbc(struct pci_dev *dev)
5405{
5406	int cap;
5407	u32 stat;
5408
5409	cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
5410	if (!cap)
5411		return -EINVAL;
5412
5413	if (pci_read_config_dword(dev, cap + PCI_X_STATUS, &stat))
5414		return -EINVAL;
5415
5416	return 512 << ((stat & PCI_X_STATUS_MAX_READ) >> 21);
5417}
5418EXPORT_SYMBOL(pcix_get_max_mmrbc);
5419
5420/**
5421 * pcix_get_mmrbc - get PCI-X maximum memory read byte count
5422 * @dev: PCI device to query
5423 *
5424 * Returns mmrbc: maximum memory read count in bytes or appropriate error
5425 * value.
5426 */
5427int pcix_get_mmrbc(struct pci_dev *dev)
5428{
5429	int cap;
5430	u16 cmd;
5431
5432	cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
5433	if (!cap)
5434		return -EINVAL;
5435
5436	if (pci_read_config_word(dev, cap + PCI_X_CMD, &cmd))
5437		return -EINVAL;
5438
5439	return 512 << ((cmd & PCI_X_CMD_MAX_READ) >> 2);
5440}
5441EXPORT_SYMBOL(pcix_get_mmrbc);
5442
5443/**
5444 * pcix_set_mmrbc - set PCI-X maximum memory read byte count
5445 * @dev: PCI device to query
5446 * @mmrbc: maximum memory read count in bytes
5447 *    valid values are 512, 1024, 2048, 4096
5448 *
5449 * If possible sets maximum memory read byte count, some bridges have errata
5450 * that prevent this.
5451 */
5452int pcix_set_mmrbc(struct pci_dev *dev, int mmrbc)
5453{
5454	int cap;
5455	u32 stat, v, o;
5456	u16 cmd;
5457
5458	if (mmrbc < 512 || mmrbc > 4096 || !is_power_of_2(mmrbc))
5459		return -EINVAL;
5460
5461	v = ffs(mmrbc) - 10;
5462
5463	cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
5464	if (!cap)
5465		return -EINVAL;
5466
5467	if (pci_read_config_dword(dev, cap + PCI_X_STATUS, &stat))
5468		return -EINVAL;
5469
5470	if (v > (stat & PCI_X_STATUS_MAX_READ) >> 21)
5471		return -E2BIG;
5472
5473	if (pci_read_config_word(dev, cap + PCI_X_CMD, &cmd))
5474		return -EINVAL;
5475
5476	o = (cmd & PCI_X_CMD_MAX_READ) >> 2;
5477	if (o != v) {
5478		if (v > o && (dev->bus->bus_flags & PCI_BUS_FLAGS_NO_MMRBC))
5479			return -EIO;
5480
5481		cmd &= ~PCI_X_CMD_MAX_READ;
5482		cmd |= v << 2;
5483		if (pci_write_config_word(dev, cap + PCI_X_CMD, cmd))
5484			return -EIO;
5485	}
5486	return 0;
5487}
5488EXPORT_SYMBOL(pcix_set_mmrbc);
5489
5490/**
5491 * pcie_get_readrq - get PCI Express read request size
5492 * @dev: PCI device to query
5493 *
5494 * Returns maximum memory read request in bytes or appropriate error value.
 
5495 */
5496int pcie_get_readrq(struct pci_dev *dev)
5497{
5498	u16 ctl;
5499
5500	pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &ctl);
5501
5502	return 128 << ((ctl & PCI_EXP_DEVCTL_READRQ) >> 12);
5503}
5504EXPORT_SYMBOL(pcie_get_readrq);
5505
5506/**
5507 * pcie_set_readrq - set PCI Express maximum memory read request
5508 * @dev: PCI device to query
5509 * @rq: maximum memory read count in bytes
5510 *    valid values are 128, 256, 512, 1024, 2048, 4096
5511 *
5512 * If possible sets maximum memory read request in bytes
5513 */
5514int pcie_set_readrq(struct pci_dev *dev, int rq)
5515{
5516	u16 v;
5517
5518	if (rq < 128 || rq > 4096 || !is_power_of_2(rq))
5519		return -EINVAL;
5520
5521	/*
5522	 * If using the "performance" PCIe config, we clamp the read rq
5523	 * size to the max packet size to keep the host bridge from
5524	 * generating requests larger than we can cope with.
 
5525	 */
5526	if (pcie_bus_config == PCIE_BUS_PERFORMANCE) {
5527		int mps = pcie_get_mps(dev);
5528
5529		if (mps < rq)
5530			rq = mps;
5531	}
5532
5533	v = (ffs(rq) - 8) << 12;
5534
5535	return pcie_capability_clear_and_set_word(dev, PCI_EXP_DEVCTL,
5536						  PCI_EXP_DEVCTL_READRQ, v);
5537}
5538EXPORT_SYMBOL(pcie_set_readrq);
5539
5540/**
5541 * pcie_get_mps - get PCI Express maximum payload size
5542 * @dev: PCI device to query
5543 *
5544 * Returns maximum payload size in bytes
5545 */
5546int pcie_get_mps(struct pci_dev *dev)
5547{
5548	u16 ctl;
5549
5550	pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &ctl);
5551
5552	return 128 << ((ctl & PCI_EXP_DEVCTL_PAYLOAD) >> 5);
5553}
5554EXPORT_SYMBOL(pcie_get_mps);
5555
5556/**
5557 * pcie_set_mps - set PCI Express maximum payload size
5558 * @dev: PCI device to query
5559 * @mps: maximum payload size in bytes
5560 *    valid values are 128, 256, 512, 1024, 2048, 4096
5561 *
5562 * If possible sets maximum payload size
5563 */
5564int pcie_set_mps(struct pci_dev *dev, int mps)
5565{
5566	u16 v;
5567
5568	if (mps < 128 || mps > 4096 || !is_power_of_2(mps))
5569		return -EINVAL;
5570
5571	v = ffs(mps) - 8;
5572	if (v > dev->pcie_mpss)
5573		return -EINVAL;
5574	v <<= 5;
5575
5576	return pcie_capability_clear_and_set_word(dev, PCI_EXP_DEVCTL,
5577						  PCI_EXP_DEVCTL_PAYLOAD, v);
5578}
5579EXPORT_SYMBOL(pcie_set_mps);
5580
5581/**
5582 * pcie_bandwidth_available - determine minimum link settings of a PCIe
5583 *			      device and its bandwidth limitation
5584 * @dev: PCI device to query
5585 * @limiting_dev: storage for device causing the bandwidth limitation
5586 * @speed: storage for speed of limiting device
5587 * @width: storage for width of limiting device
5588 *
5589 * Walk up the PCI device chain and find the point where the minimum
5590 * bandwidth is available.  Return the bandwidth available there and (if
5591 * limiting_dev, speed, and width pointers are supplied) information about
5592 * that point.  The bandwidth returned is in Mb/s, i.e., megabits/second of
5593 * raw bandwidth.
5594 */
5595u32 pcie_bandwidth_available(struct pci_dev *dev, struct pci_dev **limiting_dev,
5596			     enum pci_bus_speed *speed,
5597			     enum pcie_link_width *width)
5598{
5599	u16 lnksta;
5600	enum pci_bus_speed next_speed;
5601	enum pcie_link_width next_width;
5602	u32 bw, next_bw;
5603
5604	if (speed)
5605		*speed = PCI_SPEED_UNKNOWN;
5606	if (width)
5607		*width = PCIE_LNK_WIDTH_UNKNOWN;
5608
5609	bw = 0;
 
5610
5611	while (dev) {
5612		pcie_capability_read_word(dev, PCI_EXP_LNKSTA, &lnksta);
 
 
 
 
 
 
5613
5614		next_speed = pcie_link_speed[lnksta & PCI_EXP_LNKSTA_CLS];
5615		next_width = (lnksta & PCI_EXP_LNKSTA_NLW) >>
5616			PCI_EXP_LNKSTA_NLW_SHIFT;
5617
5618		next_bw = next_width * PCIE_SPEED2MBS_ENC(next_speed);
 
5619
5620		/* Check if current device limits the total bandwidth */
5621		if (!bw || next_bw <= bw) {
5622			bw = next_bw;
5623
5624			if (limiting_dev)
5625				*limiting_dev = dev;
5626			if (speed)
5627				*speed = next_speed;
5628			if (width)
5629				*width = next_width;
5630		}
5631
5632		dev = pci_upstream_bridge(dev);
5633	}
5634
5635	return bw;
5636}
5637EXPORT_SYMBOL(pcie_bandwidth_available);
5638
5639/**
5640 * pcie_get_speed_cap - query for the PCI device's link speed capability
5641 * @dev: PCI device to query
5642 *
5643 * Query the PCI device speed capability.  Return the maximum link speed
5644 * supported by the device.
5645 */
5646enum pci_bus_speed pcie_get_speed_cap(struct pci_dev *dev)
5647{
5648	u32 lnkcap2, lnkcap;
5649
5650	/*
5651	 * Link Capabilities 2 was added in PCIe r3.0, sec 7.8.18.  The
5652	 * implementation note there recommends using the Supported Link
5653	 * Speeds Vector in Link Capabilities 2 when supported.
5654	 *
5655	 * Without Link Capabilities 2, i.e., prior to PCIe r3.0, software
5656	 * should use the Supported Link Speeds field in Link Capabilities,
5657	 * where only 2.5 GT/s and 5.0 GT/s speeds were defined.
5658	 */
5659	pcie_capability_read_dword(dev, PCI_EXP_LNKCAP2, &lnkcap2);
5660	if (lnkcap2) { /* PCIe r3.0-compliant */
5661		if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_32_0GB)
5662			return PCIE_SPEED_32_0GT;
5663		else if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_16_0GB)
5664			return PCIE_SPEED_16_0GT;
5665		else if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_8_0GB)
5666			return PCIE_SPEED_8_0GT;
5667		else if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_5_0GB)
5668			return PCIE_SPEED_5_0GT;
5669		else if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_2_5GB)
5670			return PCIE_SPEED_2_5GT;
5671		return PCI_SPEED_UNKNOWN;
5672	}
5673
5674	pcie_capability_read_dword(dev, PCI_EXP_LNKCAP, &lnkcap);
5675	if ((lnkcap & PCI_EXP_LNKCAP_SLS) == PCI_EXP_LNKCAP_SLS_5_0GB)
5676		return PCIE_SPEED_5_0GT;
5677	else if ((lnkcap & PCI_EXP_LNKCAP_SLS) == PCI_EXP_LNKCAP_SLS_2_5GB)
5678		return PCIE_SPEED_2_5GT;
5679
5680	return PCI_SPEED_UNKNOWN;
5681}
5682EXPORT_SYMBOL(pcie_get_speed_cap);
5683
5684/**
5685 * pcie_get_width_cap - query for the PCI device's link width capability
5686 * @dev: PCI device to query
5687 *
5688 * Query the PCI device width capability.  Return the maximum link width
5689 * supported by the device.
5690 */
5691enum pcie_link_width pcie_get_width_cap(struct pci_dev *dev)
5692{
5693	u32 lnkcap;
5694
5695	pcie_capability_read_dword(dev, PCI_EXP_LNKCAP, &lnkcap);
5696	if (lnkcap)
5697		return (lnkcap & PCI_EXP_LNKCAP_MLW) >> 4;
5698
5699	return PCIE_LNK_WIDTH_UNKNOWN;
5700}
5701EXPORT_SYMBOL(pcie_get_width_cap);
5702
5703/**
5704 * pcie_bandwidth_capable - calculate a PCI device's link bandwidth capability
5705 * @dev: PCI device
5706 * @speed: storage for link speed
5707 * @width: storage for link width
5708 *
5709 * Calculate a PCI device's link bandwidth by querying for its link speed
5710 * and width, multiplying them, and applying encoding overhead.  The result
5711 * is in Mb/s, i.e., megabits/second of raw bandwidth.
5712 */
5713u32 pcie_bandwidth_capable(struct pci_dev *dev, enum pci_bus_speed *speed,
5714			   enum pcie_link_width *width)
5715{
5716	*speed = pcie_get_speed_cap(dev);
5717	*width = pcie_get_width_cap(dev);
5718
5719	if (*speed == PCI_SPEED_UNKNOWN || *width == PCIE_LNK_WIDTH_UNKNOWN)
5720		return 0;
5721
5722	return *width * PCIE_SPEED2MBS_ENC(*speed);
5723}
5724
5725/**
5726 * __pcie_print_link_status - Report the PCI device's link speed and width
5727 * @dev: PCI device to query
5728 * @verbose: Print info even when enough bandwidth is available
5729 *
5730 * If the available bandwidth at the device is less than the device is
5731 * capable of, report the device's maximum possible bandwidth and the
5732 * upstream link that limits its performance.  If @verbose, always print
5733 * the available bandwidth, even if the device isn't constrained.
5734 */
5735void __pcie_print_link_status(struct pci_dev *dev, bool verbose)
5736{
5737	enum pcie_link_width width, width_cap;
5738	enum pci_bus_speed speed, speed_cap;
5739	struct pci_dev *limiting_dev = NULL;
5740	u32 bw_avail, bw_cap;
5741
5742	bw_cap = pcie_bandwidth_capable(dev, &speed_cap, &width_cap);
5743	bw_avail = pcie_bandwidth_available(dev, &limiting_dev, &speed, &width);
5744
5745	if (bw_avail >= bw_cap && verbose)
5746		pci_info(dev, "%u.%03u Gb/s available PCIe bandwidth (%s x%d link)\n",
5747			 bw_cap / 1000, bw_cap % 1000,
5748			 PCIE_SPEED2STR(speed_cap), width_cap);
5749	else if (bw_avail < bw_cap)
5750		pci_info(dev, "%u.%03u Gb/s available PCIe bandwidth, limited by %s x%d link at %s (capable of %u.%03u Gb/s with %s x%d link)\n",
5751			 bw_avail / 1000, bw_avail % 1000,
5752			 PCIE_SPEED2STR(speed), width,
5753			 limiting_dev ? pci_name(limiting_dev) : "<unknown>",
5754			 bw_cap / 1000, bw_cap % 1000,
5755			 PCIE_SPEED2STR(speed_cap), width_cap);
5756}
5757
5758/**
5759 * pcie_print_link_status - Report the PCI device's link speed and width
5760 * @dev: PCI device to query
5761 *
5762 * Report the available bandwidth at the device.
5763 */
5764void pcie_print_link_status(struct pci_dev *dev)
5765{
5766	__pcie_print_link_status(dev, true);
5767}
5768EXPORT_SYMBOL(pcie_print_link_status);
5769
5770/**
5771 * pci_select_bars - Make BAR mask from the type of resource
5772 * @dev: the PCI device for which BAR mask is made
5773 * @flags: resource type mask to be selected
5774 *
5775 * This helper routine makes bar mask from the type of resource.
5776 */
5777int pci_select_bars(struct pci_dev *dev, unsigned long flags)
5778{
5779	int i, bars = 0;
5780	for (i = 0; i < PCI_NUM_RESOURCES; i++)
5781		if (pci_resource_flags(dev, i) & flags)
5782			bars |= (1 << i);
5783	return bars;
5784}
5785EXPORT_SYMBOL(pci_select_bars);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5786
5787/* Some architectures require additional programming to enable VGA */
5788static arch_set_vga_state_t arch_set_vga_state;
5789
5790void __init pci_register_set_vga_state(arch_set_vga_state_t func)
5791{
5792	arch_set_vga_state = func;	/* NULL disables */
5793}
5794
5795static int pci_set_vga_state_arch(struct pci_dev *dev, bool decode,
5796				  unsigned int command_bits, u32 flags)
5797{
5798	if (arch_set_vga_state)
5799		return arch_set_vga_state(dev, decode, command_bits,
5800						flags);
5801	return 0;
5802}
5803
5804/**
5805 * pci_set_vga_state - set VGA decode state on device and parents if requested
5806 * @dev: the PCI device
5807 * @decode: true = enable decoding, false = disable decoding
5808 * @command_bits: PCI_COMMAND_IO and/or PCI_COMMAND_MEMORY
5809 * @flags: traverse ancestors and change bridges
5810 * CHANGE_BRIDGE_ONLY / CHANGE_BRIDGE
5811 */
5812int pci_set_vga_state(struct pci_dev *dev, bool decode,
5813		      unsigned int command_bits, u32 flags)
5814{
5815	struct pci_bus *bus;
5816	struct pci_dev *bridge;
5817	u16 cmd;
5818	int rc;
5819
5820	WARN_ON((flags & PCI_VGA_STATE_CHANGE_DECODES) && (command_bits & ~(PCI_COMMAND_IO|PCI_COMMAND_MEMORY)));
5821
5822	/* ARCH specific VGA enables */
5823	rc = pci_set_vga_state_arch(dev, decode, command_bits, flags);
5824	if (rc)
5825		return rc;
5826
5827	if (flags & PCI_VGA_STATE_CHANGE_DECODES) {
5828		pci_read_config_word(dev, PCI_COMMAND, &cmd);
5829		if (decode == true)
5830			cmd |= command_bits;
5831		else
5832			cmd &= ~command_bits;
5833		pci_write_config_word(dev, PCI_COMMAND, cmd);
5834	}
5835
5836	if (!(flags & PCI_VGA_STATE_CHANGE_BRIDGE))
5837		return 0;
5838
5839	bus = dev->bus;
5840	while (bus) {
5841		bridge = bus->self;
5842		if (bridge) {
5843			pci_read_config_word(bridge, PCI_BRIDGE_CONTROL,
5844					     &cmd);
5845			if (decode == true)
5846				cmd |= PCI_BRIDGE_CTL_VGA;
5847			else
5848				cmd &= ~PCI_BRIDGE_CTL_VGA;
5849			pci_write_config_word(bridge, PCI_BRIDGE_CONTROL,
5850					      cmd);
5851		}
5852		bus = bus->parent;
5853	}
5854	return 0;
5855}
5856
5857/**
5858 * pci_add_dma_alias - Add a DMA devfn alias for a device
5859 * @dev: the PCI device for which alias is added
5860 * @devfn: alias slot and function
5861 *
5862 * This helper encodes an 8-bit devfn as a bit number in dma_alias_mask
5863 * which is used to program permissible bus-devfn source addresses for DMA
5864 * requests in an IOMMU.  These aliases factor into IOMMU group creation
5865 * and are useful for devices generating DMA requests beyond or different
5866 * from their logical bus-devfn.  Examples include device quirks where the
5867 * device simply uses the wrong devfn, as well as non-transparent bridges
5868 * where the alias may be a proxy for devices in another domain.
5869 *
5870 * IOMMU group creation is performed during device discovery or addition,
5871 * prior to any potential DMA mapping and therefore prior to driver probing
5872 * (especially for userspace assigned devices where IOMMU group definition
5873 * cannot be left as a userspace activity).  DMA aliases should therefore
5874 * be configured via quirks, such as the PCI fixup header quirk.
5875 */
5876void pci_add_dma_alias(struct pci_dev *dev, u8 devfn)
5877{
5878	if (!dev->dma_alias_mask)
5879		dev->dma_alias_mask = bitmap_zalloc(U8_MAX, GFP_KERNEL);
5880	if (!dev->dma_alias_mask) {
5881		pci_warn(dev, "Unable to allocate DMA alias mask\n");
5882		return;
5883	}
5884
5885	set_bit(devfn, dev->dma_alias_mask);
5886	pci_info(dev, "Enabling fixed DMA alias to %02x.%d\n",
5887		 PCI_SLOT(devfn), PCI_FUNC(devfn));
5888}
5889
5890bool pci_devs_are_dma_aliases(struct pci_dev *dev1, struct pci_dev *dev2)
5891{
5892	return (dev1->dma_alias_mask &&
5893		test_bit(dev2->devfn, dev1->dma_alias_mask)) ||
5894	       (dev2->dma_alias_mask &&
5895		test_bit(dev1->devfn, dev2->dma_alias_mask));
5896}
5897
5898bool pci_device_is_present(struct pci_dev *pdev)
5899{
5900	u32 v;
5901
5902	if (pci_dev_is_disconnected(pdev))
5903		return false;
5904	return pci_bus_read_dev_vendor_id(pdev->bus, pdev->devfn, &v, 0);
5905}
5906EXPORT_SYMBOL_GPL(pci_device_is_present);
5907
5908void pci_ignore_hotplug(struct pci_dev *dev)
5909{
5910	struct pci_dev *bridge = dev->bus->self;
5911
5912	dev->ignore_hotplug = 1;
5913	/* Propagate the "ignore hotplug" setting to the parent bridge. */
5914	if (bridge)
5915		bridge->ignore_hotplug = 1;
5916}
5917EXPORT_SYMBOL_GPL(pci_ignore_hotplug);
5918
5919resource_size_t __weak pcibios_default_alignment(void)
5920{
5921	return 0;
5922}
5923
5924/*
5925 * Arches that don't want to expose struct resource to userland as-is in
5926 * sysfs and /proc can implement their own pci_resource_to_user().
5927 */
5928void __weak pci_resource_to_user(const struct pci_dev *dev, int bar,
5929				 const struct resource *rsrc,
5930				 resource_size_t *start, resource_size_t *end)
5931{
5932	*start = rsrc->start;
5933	*end = rsrc->end;
5934}
5935
5936static char *resource_alignment_param;
5937static DEFINE_SPINLOCK(resource_alignment_lock);
5938
5939/**
5940 * pci_specified_resource_alignment - get resource alignment specified by user.
5941 * @dev: the PCI device to get
5942 * @resize: whether or not to change resources' size when reassigning alignment
5943 *
5944 * RETURNS: Resource alignment if it is specified.
5945 *          Zero if it is not specified.
5946 */
5947static resource_size_t pci_specified_resource_alignment(struct pci_dev *dev,
5948							bool *resize)
5949{
5950	int align_order, count;
5951	resource_size_t align = pcibios_default_alignment();
5952	const char *p;
5953	int ret;
5954
5955	spin_lock(&resource_alignment_lock);
5956	p = resource_alignment_param;
5957	if (!p || !*p)
5958		goto out;
5959	if (pci_has_flag(PCI_PROBE_ONLY)) {
5960		align = 0;
5961		pr_info_once("PCI: Ignoring requested alignments (PCI_PROBE_ONLY)\n");
5962		goto out;
5963	}
5964
5965	while (*p) {
5966		count = 0;
5967		if (sscanf(p, "%d%n", &align_order, &count) == 1 &&
5968							p[count] == '@') {
5969			p += count + 1;
5970		} else {
5971			align_order = -1;
5972		}
5973
5974		ret = pci_dev_str_match(dev, p, &p);
5975		if (ret == 1) {
5976			*resize = true;
5977			if (align_order == -1)
 
 
 
 
 
 
 
 
 
 
 
 
5978				align = PAGE_SIZE;
5979			else
5980				align = 1 << align_order;
5981			break;
5982		} else if (ret < 0) {
5983			pr_err("PCI: Can't parse resource_alignment parameter: %s\n",
5984			       p);
5985			break;
5986		}
5987
5988		if (*p != ';' && *p != ',') {
5989			/* End of param or invalid format */
5990			break;
5991		}
5992		p++;
5993	}
5994out:
5995	spin_unlock(&resource_alignment_lock);
5996	return align;
5997}
5998
5999static void pci_request_resource_alignment(struct pci_dev *dev, int bar,
6000					   resource_size_t align, bool resize)
6001{
6002	struct resource *r = &dev->resource[bar];
6003	resource_size_t size;
6004
6005	if (!(r->flags & IORESOURCE_MEM))
6006		return;
6007
6008	if (r->flags & IORESOURCE_PCI_FIXED) {
6009		pci_info(dev, "BAR%d %pR: ignoring requested alignment %#llx\n",
6010			 bar, r, (unsigned long long)align);
6011		return;
6012	}
6013
6014	size = resource_size(r);
6015	if (size >= align)
6016		return;
6017
6018	/*
6019	 * Increase the alignment of the resource.  There are two ways we
6020	 * can do this:
6021	 *
6022	 * 1) Increase the size of the resource.  BARs are aligned on their
6023	 *    size, so when we reallocate space for this resource, we'll
6024	 *    allocate it with the larger alignment.  This also prevents
6025	 *    assignment of any other BARs inside the alignment region, so
6026	 *    if we're requesting page alignment, this means no other BARs
6027	 *    will share the page.
6028	 *
6029	 *    The disadvantage is that this makes the resource larger than
6030	 *    the hardware BAR, which may break drivers that compute things
6031	 *    based on the resource size, e.g., to find registers at a
6032	 *    fixed offset before the end of the BAR.
6033	 *
6034	 * 2) Retain the resource size, but use IORESOURCE_STARTALIGN and
6035	 *    set r->start to the desired alignment.  By itself this
6036	 *    doesn't prevent other BARs being put inside the alignment
6037	 *    region, but if we realign *every* resource of every device in
6038	 *    the system, none of them will share an alignment region.
6039	 *
6040	 * When the user has requested alignment for only some devices via
6041	 * the "pci=resource_alignment" argument, "resize" is true and we
6042	 * use the first method.  Otherwise we assume we're aligning all
6043	 * devices and we use the second.
6044	 */
6045
6046	pci_info(dev, "BAR%d %pR: requesting alignment to %#llx\n",
6047		 bar, r, (unsigned long long)align);
6048
6049	if (resize) {
6050		r->start = 0;
6051		r->end = align - 1;
6052	} else {
6053		r->flags &= ~IORESOURCE_SIZEALIGN;
6054		r->flags |= IORESOURCE_STARTALIGN;
6055		r->start = align;
6056		r->end = r->start + size - 1;
6057	}
6058	r->flags |= IORESOURCE_UNSET;
6059}
6060
6061/*
6062 * This function disables memory decoding and releases memory resources
6063 * of the device specified by kernel's boot parameter 'pci=resource_alignment='.
6064 * It also rounds up size to specified alignment.
6065 * Later on, the kernel will assign page-aligned memory resource back
6066 * to the device.
6067 */
6068void pci_reassigndev_resource_alignment(struct pci_dev *dev)
6069{
6070	int i;
6071	struct resource *r;
6072	resource_size_t align;
6073	u16 command;
6074	bool resize = false;
6075
6076	/*
6077	 * VF BARs are read-only zero according to SR-IOV spec r1.1, sec
6078	 * 3.4.1.11.  Their resources are allocated from the space
6079	 * described by the VF BARx register in the PF's SR-IOV capability.
6080	 * We can't influence their alignment here.
6081	 */
6082	if (dev->is_virtfn)
6083		return;
6084
6085	/* check if specified PCI is target device to reassign */
6086	align = pci_specified_resource_alignment(dev, &resize);
6087	if (!align)
6088		return;
6089
6090	if (dev->hdr_type == PCI_HEADER_TYPE_NORMAL &&
6091	    (dev->class >> 8) == PCI_CLASS_BRIDGE_HOST) {
6092		pci_warn(dev, "Can't reassign resources to host bridge\n");
 
6093		return;
6094	}
6095
 
 
6096	pci_read_config_word(dev, PCI_COMMAND, &command);
6097	command &= ~PCI_COMMAND_MEMORY;
6098	pci_write_config_word(dev, PCI_COMMAND, command);
6099
6100	for (i = 0; i <= PCI_ROM_RESOURCE; i++)
6101		pci_request_resource_alignment(dev, i, align, resize);
6102
6103	/*
6104	 * Need to disable bridge's resource window,
 
 
 
 
 
 
 
 
 
 
 
6105	 * to enable the kernel to reassign new resource
6106	 * window later on.
6107	 */
6108	if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
 
6109		for (i = PCI_BRIDGE_RESOURCES; i < PCI_NUM_RESOURCES; i++) {
6110			r = &dev->resource[i];
6111			if (!(r->flags & IORESOURCE_MEM))
6112				continue;
6113			r->flags |= IORESOURCE_UNSET;
6114			r->end = resource_size(r) - 1;
6115			r->start = 0;
6116		}
6117		pci_disable_bridge_window(dev);
6118	}
6119}
6120
6121static ssize_t resource_alignment_show(struct bus_type *bus, char *buf)
6122{
6123	size_t count = 0;
6124
6125	spin_lock(&resource_alignment_lock);
6126	if (resource_alignment_param)
6127		count = snprintf(buf, PAGE_SIZE, "%s", resource_alignment_param);
6128	spin_unlock(&resource_alignment_lock);
6129
6130	/*
6131	 * When set by the command line, resource_alignment_param will not
6132	 * have a trailing line feed, which is ugly. So conditionally add
6133	 * it here.
6134	 */
6135	if (count >= 2 && buf[count - 2] != '\n' && count < PAGE_SIZE - 1) {
6136		buf[count - 1] = '\n';
6137		buf[count++] = 0;
6138	}
6139
6140	return count;
6141}
6142
6143static ssize_t resource_alignment_store(struct bus_type *bus,
6144					const char *buf, size_t count)
6145{
6146	char *param = kstrndup(buf, count, GFP_KERNEL);
6147
6148	if (!param)
6149		return -ENOMEM;
6150
6151	spin_lock(&resource_alignment_lock);
6152	kfree(resource_alignment_param);
6153	resource_alignment_param = param;
6154	spin_unlock(&resource_alignment_lock);
6155	return count;
6156}
6157
6158static BUS_ATTR_RW(resource_alignment);
 
 
 
 
 
 
 
 
 
 
 
 
6159
6160static int __init pci_resource_alignment_sysfs_init(void)
6161{
6162	return bus_create_file(&pci_bus_type,
6163					&bus_attr_resource_alignment);
6164}
 
6165late_initcall(pci_resource_alignment_sysfs_init);
6166
6167static void pci_no_domains(void)
6168{
6169#ifdef CONFIG_PCI_DOMAINS
6170	pci_domains_supported = 0;
6171#endif
6172}
6173
6174#ifdef CONFIG_PCI_DOMAINS_GENERIC
6175static atomic_t __domain_nr = ATOMIC_INIT(-1);
6176
6177static int pci_get_new_domain_nr(void)
6178{
6179	return atomic_inc_return(&__domain_nr);
6180}
6181
6182static int of_pci_bus_find_domain_nr(struct device *parent)
6183{
6184	static int use_dt_domains = -1;
6185	int domain = -1;
6186
6187	if (parent)
6188		domain = of_get_pci_domain_nr(parent->of_node);
6189
6190	/*
6191	 * Check DT domain and use_dt_domains values.
6192	 *
6193	 * If DT domain property is valid (domain >= 0) and
6194	 * use_dt_domains != 0, the DT assignment is valid since this means
6195	 * we have not previously allocated a domain number by using
6196	 * pci_get_new_domain_nr(); we should also update use_dt_domains to
6197	 * 1, to indicate that we have just assigned a domain number from
6198	 * DT.
6199	 *
6200	 * If DT domain property value is not valid (ie domain < 0), and we
6201	 * have not previously assigned a domain number from DT
6202	 * (use_dt_domains != 1) we should assign a domain number by
6203	 * using the:
6204	 *
6205	 * pci_get_new_domain_nr()
6206	 *
6207	 * API and update the use_dt_domains value to keep track of method we
6208	 * are using to assign domain numbers (use_dt_domains = 0).
6209	 *
6210	 * All other combinations imply we have a platform that is trying
6211	 * to mix domain numbers obtained from DT and pci_get_new_domain_nr(),
6212	 * which is a recipe for domain mishandling and it is prevented by
6213	 * invalidating the domain value (domain = -1) and printing a
6214	 * corresponding error.
6215	 */
6216	if (domain >= 0 && use_dt_domains) {
6217		use_dt_domains = 1;
6218	} else if (domain < 0 && use_dt_domains != 1) {
6219		use_dt_domains = 0;
6220		domain = pci_get_new_domain_nr();
6221	} else {
6222		if (parent)
6223			pr_err("Node %pOF has ", parent->of_node);
6224		pr_err("Inconsistent \"linux,pci-domain\" property in DT\n");
6225		domain = -1;
6226	}
6227
6228	return domain;
6229}
6230
6231int pci_bus_find_domain_nr(struct pci_bus *bus, struct device *parent)
6232{
6233	return acpi_disabled ? of_pci_bus_find_domain_nr(parent) :
6234			       acpi_pci_bus_find_domain_nr(bus);
6235}
6236#endif
6237
6238/**
6239 * pci_ext_cfg_avail - can we access extended PCI config space?
6240 *
6241 * Returns 1 if we can access PCI extended config space (offsets
6242 * greater than 0xff). This is the default implementation. Architecture
6243 * implementations can override this.
6244 */
6245int __weak pci_ext_cfg_avail(void)
6246{
6247	return 1;
6248}
6249
6250void __weak pci_fixup_cardbus(struct pci_bus *bus)
6251{
6252}
6253EXPORT_SYMBOL(pci_fixup_cardbus);
6254
6255static int __init pci_setup(char *str)
6256{
6257	while (str) {
6258		char *k = strchr(str, ',');
6259		if (k)
6260			*k++ = 0;
6261		if (*str && (str = pcibios_setup(str)) && *str) {
6262			if (!strcmp(str, "nomsi")) {
6263				pci_no_msi();
6264			} else if (!strncmp(str, "noats", 5)) {
6265				pr_info("PCIe: ATS is disabled\n");
6266				pcie_ats_disabled = true;
6267			} else if (!strcmp(str, "noaer")) {
6268				pci_no_aer();
6269			} else if (!strcmp(str, "earlydump")) {
6270				pci_early_dump = true;
6271			} else if (!strncmp(str, "realloc=", 8)) {
6272				pci_realloc_get_opt(str + 8);
6273			} else if (!strncmp(str, "realloc", 7)) {
6274				pci_realloc_get_opt("on");
6275			} else if (!strcmp(str, "nodomains")) {
6276				pci_no_domains();
6277			} else if (!strncmp(str, "noari", 5)) {
6278				pcie_ari_disabled = true;
6279			} else if (!strncmp(str, "cbiosize=", 9)) {
6280				pci_cardbus_io_size = memparse(str + 9, &str);
6281			} else if (!strncmp(str, "cbmemsize=", 10)) {
6282				pci_cardbus_mem_size = memparse(str + 10, &str);
6283			} else if (!strncmp(str, "resource_alignment=", 19)) {
6284				resource_alignment_param = str + 19;
 
6285			} else if (!strncmp(str, "ecrc=", 5)) {
6286				pcie_ecrc_get_policy(str + 5);
6287			} else if (!strncmp(str, "hpiosize=", 9)) {
6288				pci_hotplug_io_size = memparse(str + 9, &str);
6289			} else if (!strncmp(str, "hpmemsize=", 10)) {
6290				pci_hotplug_mem_size = memparse(str + 10, &str);
6291			} else if (!strncmp(str, "hpbussize=", 10)) {
6292				pci_hotplug_bus_size =
6293					simple_strtoul(str + 10, &str, 0);
6294				if (pci_hotplug_bus_size > 0xff)
6295					pci_hotplug_bus_size = DEFAULT_HOTPLUG_BUS_SIZE;
6296			} else if (!strncmp(str, "pcie_bus_tune_off", 17)) {
6297				pcie_bus_config = PCIE_BUS_TUNE_OFF;
6298			} else if (!strncmp(str, "pcie_bus_safe", 13)) {
6299				pcie_bus_config = PCIE_BUS_SAFE;
6300			} else if (!strncmp(str, "pcie_bus_perf", 13)) {
6301				pcie_bus_config = PCIE_BUS_PERFORMANCE;
6302			} else if (!strncmp(str, "pcie_bus_peer2peer", 18)) {
6303				pcie_bus_config = PCIE_BUS_PEER2PEER;
6304			} else if (!strncmp(str, "pcie_scan_all", 13)) {
6305				pci_add_flags(PCI_SCAN_ALL_PCIE_DEVS);
6306			} else if (!strncmp(str, "disable_acs_redir=", 18)) {
6307				disable_acs_redir_param = str + 18;
6308			} else {
6309				pr_err("PCI: Unknown option `%s'\n", str);
 
6310			}
6311		}
6312		str = k;
6313	}
6314	return 0;
6315}
6316early_param("pci", pci_setup);
6317
6318/*
6319 * 'resource_alignment_param' and 'disable_acs_redir_param' are initialized
6320 * in pci_setup(), above, to point to data in the __initdata section which
6321 * will be freed after the init sequence is complete. We can't allocate memory
6322 * in pci_setup() because some architectures do not have any memory allocation
6323 * service available during an early_param() call. So we allocate memory and
6324 * copy the variable here before the init section is freed.
6325 *
6326 */
6327static int __init pci_realloc_setup_params(void)
6328{
6329	resource_alignment_param = kstrdup(resource_alignment_param,
6330					   GFP_KERNEL);
6331	disable_acs_redir_param = kstrdup(disable_acs_redir_param, GFP_KERNEL);
 
 
 
 
 
 
 
 
 
 
 
 
 
6332
6333	return 0;
6334}
6335pure_initcall(pci_realloc_setup_params);
 
 
 
 
 
 
v3.15
 
   1/*
   2 *	PCI Bus Services, see include/linux/pci.h for further explanation.
   3 *
   4 *	Copyright 1993 -- 1997 Drew Eckhardt, Frederic Potter,
   5 *	David Mosberger-Tang
   6 *
   7 *	Copyright 1997 -- 2000 Martin Mares <mj@ucw.cz>
   8 */
   9
 
  10#include <linux/kernel.h>
  11#include <linux/delay.h>
 
  12#include <linux/init.h>
 
 
  13#include <linux/pci.h>
  14#include <linux/pm.h>
  15#include <linux/slab.h>
  16#include <linux/module.h>
  17#include <linux/spinlock.h>
  18#include <linux/string.h>
  19#include <linux/log2.h>
  20#include <linux/pci-aspm.h>
  21#include <linux/pm_wakeup.h>
  22#include <linux/interrupt.h>
  23#include <linux/device.h>
  24#include <linux/pm_runtime.h>
  25#include <linux/pci_hotplug.h>
  26#include <asm-generic/pci-bridge.h>
 
  27#include <asm/setup.h>
 
 
  28#include "pci.h"
  29
 
 
  30const char *pci_power_names[] = {
  31	"error", "D0", "D1", "D2", "D3hot", "D3cold", "unknown",
  32};
  33EXPORT_SYMBOL_GPL(pci_power_names);
  34
  35int isa_dma_bridge_buggy;
  36EXPORT_SYMBOL(isa_dma_bridge_buggy);
  37
  38int pci_pci_problems;
  39EXPORT_SYMBOL(pci_pci_problems);
  40
  41unsigned int pci_pm_d3_delay;
  42
  43static void pci_pme_list_scan(struct work_struct *work);
  44
  45static LIST_HEAD(pci_pme_list);
  46static DEFINE_MUTEX(pci_pme_list_mutex);
  47static DECLARE_DELAYED_WORK(pci_pme_work, pci_pme_list_scan);
  48
  49struct pci_pme_device {
  50	struct list_head list;
  51	struct pci_dev *dev;
  52};
  53
  54#define PME_TIMEOUT 1000 /* How long between PME checks */
  55
  56static void pci_dev_d3_sleep(struct pci_dev *dev)
  57{
  58	unsigned int delay = dev->d3_delay;
  59
  60	if (delay < pci_pm_d3_delay)
  61		delay = pci_pm_d3_delay;
  62
  63	msleep(delay);
 
  64}
  65
  66#ifdef CONFIG_PCI_DOMAINS
  67int pci_domains_supported = 1;
  68#endif
  69
  70#define DEFAULT_CARDBUS_IO_SIZE		(256)
  71#define DEFAULT_CARDBUS_MEM_SIZE	(64*1024*1024)
  72/* pci=cbmemsize=nnM,cbiosize=nn can override this */
  73unsigned long pci_cardbus_io_size = DEFAULT_CARDBUS_IO_SIZE;
  74unsigned long pci_cardbus_mem_size = DEFAULT_CARDBUS_MEM_SIZE;
  75
  76#define DEFAULT_HOTPLUG_IO_SIZE		(256)
  77#define DEFAULT_HOTPLUG_MEM_SIZE	(2*1024*1024)
  78/* pci=hpmemsize=nnM,hpiosize=nn can override this */
  79unsigned long pci_hotplug_io_size  = DEFAULT_HOTPLUG_IO_SIZE;
  80unsigned long pci_hotplug_mem_size = DEFAULT_HOTPLUG_MEM_SIZE;
  81
  82enum pcie_bus_config_types pcie_bus_config = PCIE_BUS_TUNE_OFF;
 
 
 
  83
  84/*
  85 * The default CLS is used if arch didn't set CLS explicitly and not
  86 * all pci devices agree on the same value.  Arch can override either
  87 * the dfl or actual value as it sees fit.  Don't forget this is
  88 * measured in 32-bit words, not bytes.
  89 */
  90u8 pci_dfl_cache_line_size = L1_CACHE_BYTES >> 2;
  91u8 pci_cache_line_size;
  92
  93/*
  94 * If we set up a device for bus mastering, we need to check the latency
  95 * timer as certain BIOSes forget to set it properly.
  96 */
  97unsigned int pcibios_max_latency = 255;
  98
  99/* If set, the PCIe ARI capability will not be used. */
 100static bool pcie_ari_disabled;
 101
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 102/**
 103 * pci_bus_max_busnr - returns maximum PCI bus number of given bus' children
 104 * @bus: pointer to PCI bus structure to search
 105 *
 106 * Given a PCI bus, returns the highest PCI bus number present in the set
 107 * including the given PCI bus and its list of child PCI buses.
 108 */
 109unsigned char pci_bus_max_busnr(struct pci_bus* bus)
 110{
 111	struct pci_bus *tmp;
 112	unsigned char max, n;
 113
 114	max = bus->busn_res.end;
 115	list_for_each_entry(tmp, &bus->children, node) {
 116		n = pci_bus_max_busnr(tmp);
 117		if(n > max)
 118			max = n;
 119	}
 120	return max;
 121}
 122EXPORT_SYMBOL_GPL(pci_bus_max_busnr);
 123
 124#ifdef CONFIG_HAS_IOMEM
 125void __iomem *pci_ioremap_bar(struct pci_dev *pdev, int bar)
 126{
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 127	/*
 128	 * Make sure the BAR is actually a memory resource, not an IO resource
 129	 */
 130	if (!(pci_resource_flags(pdev, bar) & IORESOURCE_MEM)) {
 131		WARN_ON(1);
 132		return NULL;
 133	}
 134	return ioremap_nocache(pci_resource_start(pdev, bar),
 135				     pci_resource_len(pdev, bar));
 136}
 137EXPORT_SYMBOL_GPL(pci_ioremap_bar);
 138#endif
 139
 140#define PCI_FIND_CAP_TTL	48
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 141
 142static int __pci_find_next_cap_ttl(struct pci_bus *bus, unsigned int devfn,
 143				   u8 pos, int cap, int *ttl)
 144{
 145	u8 id;
 
 
 
 146
 147	while ((*ttl)--) {
 148		pci_bus_read_config_byte(bus, devfn, pos, &pos);
 149		if (pos < 0x40)
 150			break;
 151		pos &= ~3;
 152		pci_bus_read_config_byte(bus, devfn, pos + PCI_CAP_LIST_ID,
 153					 &id);
 
 154		if (id == 0xff)
 155			break;
 156		if (id == cap)
 157			return pos;
 158		pos += PCI_CAP_LIST_NEXT;
 159	}
 160	return 0;
 161}
 162
 163static int __pci_find_next_cap(struct pci_bus *bus, unsigned int devfn,
 164			       u8 pos, int cap)
 165{
 166	int ttl = PCI_FIND_CAP_TTL;
 167
 168	return __pci_find_next_cap_ttl(bus, devfn, pos, cap, &ttl);
 169}
 170
 171int pci_find_next_capability(struct pci_dev *dev, u8 pos, int cap)
 172{
 173	return __pci_find_next_cap(dev->bus, dev->devfn,
 174				   pos + PCI_CAP_LIST_NEXT, cap);
 175}
 176EXPORT_SYMBOL_GPL(pci_find_next_capability);
 177
 178static int __pci_bus_find_cap_start(struct pci_bus *bus,
 179				    unsigned int devfn, u8 hdr_type)
 180{
 181	u16 status;
 182
 183	pci_bus_read_config_word(bus, devfn, PCI_STATUS, &status);
 184	if (!(status & PCI_STATUS_CAP_LIST))
 185		return 0;
 186
 187	switch (hdr_type) {
 188	case PCI_HEADER_TYPE_NORMAL:
 189	case PCI_HEADER_TYPE_BRIDGE:
 190		return PCI_CAPABILITY_LIST;
 191	case PCI_HEADER_TYPE_CARDBUS:
 192		return PCI_CB_CAPABILITY_LIST;
 193	default:
 194		return 0;
 195	}
 196
 197	return 0;
 198}
 199
 200/**
 201 * pci_find_capability - query for devices' capabilities
 202 * @dev: PCI device to query
 203 * @cap: capability code
 204 *
 205 * Tell if a device supports a given PCI capability.
 206 * Returns the address of the requested capability structure within the
 207 * device's PCI configuration space or 0 in case the device does not
 208 * support it.  Possible values for @cap:
 209 *
 210 *  %PCI_CAP_ID_PM           Power Management
 211 *  %PCI_CAP_ID_AGP          Accelerated Graphics Port
 212 *  %PCI_CAP_ID_VPD          Vital Product Data
 213 *  %PCI_CAP_ID_SLOTID       Slot Identification
 214 *  %PCI_CAP_ID_MSI          Message Signalled Interrupts
 215 *  %PCI_CAP_ID_CHSWP        CompactPCI HotSwap
 216 *  %PCI_CAP_ID_PCIX         PCI-X
 217 *  %PCI_CAP_ID_EXP          PCI Express
 218 */
 219int pci_find_capability(struct pci_dev *dev, int cap)
 220{
 221	int pos;
 222
 223	pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
 224	if (pos)
 225		pos = __pci_find_next_cap(dev->bus, dev->devfn, pos, cap);
 226
 227	return pos;
 228}
 
 229
 230/**
 231 * pci_bus_find_capability - query for devices' capabilities
 232 * @bus:   the PCI bus to query
 233 * @devfn: PCI device to query
 234 * @cap:   capability code
 235 *
 236 * Like pci_find_capability() but works for pci devices that do not have a
 237 * pci_dev structure set up yet.
 238 *
 239 * Returns the address of the requested capability structure within the
 240 * device's PCI configuration space or 0 in case the device does not
 241 * support it.
 242 */
 243int pci_bus_find_capability(struct pci_bus *bus, unsigned int devfn, int cap)
 244{
 245	int pos;
 246	u8 hdr_type;
 247
 248	pci_bus_read_config_byte(bus, devfn, PCI_HEADER_TYPE, &hdr_type);
 249
 250	pos = __pci_bus_find_cap_start(bus, devfn, hdr_type & 0x7f);
 251	if (pos)
 252		pos = __pci_find_next_cap(bus, devfn, pos, cap);
 253
 254	return pos;
 255}
 
 256
 257/**
 258 * pci_find_next_ext_capability - Find an extended capability
 259 * @dev: PCI device to query
 260 * @start: address at which to start looking (0 to start at beginning of list)
 261 * @cap: capability code
 262 *
 263 * Returns the address of the next matching extended capability structure
 264 * within the device's PCI configuration space or 0 if the device does
 265 * not support it.  Some capabilities can occur several times, e.g., the
 266 * vendor-specific capability, and this provides a way to find them all.
 267 */
 268int pci_find_next_ext_capability(struct pci_dev *dev, int start, int cap)
 269{
 270	u32 header;
 271	int ttl;
 272	int pos = PCI_CFG_SPACE_SIZE;
 273
 274	/* minimum 8 bytes per capability */
 275	ttl = (PCI_CFG_SPACE_EXP_SIZE - PCI_CFG_SPACE_SIZE) / 8;
 276
 277	if (dev->cfg_size <= PCI_CFG_SPACE_SIZE)
 278		return 0;
 279
 280	if (start)
 281		pos = start;
 282
 283	if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
 284		return 0;
 285
 286	/*
 287	 * If we have no capabilities, this is indicated by cap ID,
 288	 * cap version and next pointer all being 0.
 289	 */
 290	if (header == 0)
 291		return 0;
 292
 293	while (ttl-- > 0) {
 294		if (PCI_EXT_CAP_ID(header) == cap && pos != start)
 295			return pos;
 296
 297		pos = PCI_EXT_CAP_NEXT(header);
 298		if (pos < PCI_CFG_SPACE_SIZE)
 299			break;
 300
 301		if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
 302			break;
 303	}
 304
 305	return 0;
 306}
 307EXPORT_SYMBOL_GPL(pci_find_next_ext_capability);
 308
 309/**
 310 * pci_find_ext_capability - Find an extended capability
 311 * @dev: PCI device to query
 312 * @cap: capability code
 313 *
 314 * Returns the address of the requested extended capability structure
 315 * within the device's PCI configuration space or 0 if the device does
 316 * not support it.  Possible values for @cap:
 317 *
 318 *  %PCI_EXT_CAP_ID_ERR		Advanced Error Reporting
 319 *  %PCI_EXT_CAP_ID_VC		Virtual Channel
 320 *  %PCI_EXT_CAP_ID_DSN		Device Serial Number
 321 *  %PCI_EXT_CAP_ID_PWR		Power Budgeting
 322 */
 323int pci_find_ext_capability(struct pci_dev *dev, int cap)
 324{
 325	return pci_find_next_ext_capability(dev, 0, cap);
 326}
 327EXPORT_SYMBOL_GPL(pci_find_ext_capability);
 328
 329static int __pci_find_next_ht_cap(struct pci_dev *dev, int pos, int ht_cap)
 330{
 331	int rc, ttl = PCI_FIND_CAP_TTL;
 332	u8 cap, mask;
 333
 334	if (ht_cap == HT_CAPTYPE_SLAVE || ht_cap == HT_CAPTYPE_HOST)
 335		mask = HT_3BIT_CAP_MASK;
 336	else
 337		mask = HT_5BIT_CAP_MASK;
 338
 339	pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn, pos,
 340				      PCI_CAP_ID_HT, &ttl);
 341	while (pos) {
 342		rc = pci_read_config_byte(dev, pos + 3, &cap);
 343		if (rc != PCIBIOS_SUCCESSFUL)
 344			return 0;
 345
 346		if ((cap & mask) == ht_cap)
 347			return pos;
 348
 349		pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn,
 350					      pos + PCI_CAP_LIST_NEXT,
 351					      PCI_CAP_ID_HT, &ttl);
 352	}
 353
 354	return 0;
 355}
 356/**
 357 * pci_find_next_ht_capability - query a device's Hypertransport capabilities
 358 * @dev: PCI device to query
 359 * @pos: Position from which to continue searching
 360 * @ht_cap: Hypertransport capability code
 361 *
 362 * To be used in conjunction with pci_find_ht_capability() to search for
 363 * all capabilities matching @ht_cap. @pos should always be a value returned
 364 * from pci_find_ht_capability().
 365 *
 366 * NB. To be 100% safe against broken PCI devices, the caller should take
 367 * steps to avoid an infinite loop.
 368 */
 369int pci_find_next_ht_capability(struct pci_dev *dev, int pos, int ht_cap)
 370{
 371	return __pci_find_next_ht_cap(dev, pos + PCI_CAP_LIST_NEXT, ht_cap);
 372}
 373EXPORT_SYMBOL_GPL(pci_find_next_ht_capability);
 374
 375/**
 376 * pci_find_ht_capability - query a device's Hypertransport capabilities
 377 * @dev: PCI device to query
 378 * @ht_cap: Hypertransport capability code
 379 *
 380 * Tell if a device supports a given Hypertransport capability.
 381 * Returns an address within the device's PCI configuration space
 382 * or 0 in case the device does not support the request capability.
 383 * The address points to the PCI capability, of type PCI_CAP_ID_HT,
 384 * which has a Hypertransport capability matching @ht_cap.
 385 */
 386int pci_find_ht_capability(struct pci_dev *dev, int ht_cap)
 387{
 388	int pos;
 389
 390	pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
 391	if (pos)
 392		pos = __pci_find_next_ht_cap(dev, pos, ht_cap);
 393
 394	return pos;
 395}
 396EXPORT_SYMBOL_GPL(pci_find_ht_capability);
 397
 398/**
 399 * pci_find_parent_resource - return resource region of parent bus of given region
 
 400 * @dev: PCI device structure contains resources to be searched
 401 * @res: child resource record for which parent is sought
 402 *
 403 *  For given resource region of given device, return the resource
 404 *  region of parent bus the given region is contained in.
 405 */
 406struct resource *
 407pci_find_parent_resource(const struct pci_dev *dev, struct resource *res)
 408{
 409	const struct pci_bus *bus = dev->bus;
 410	struct resource *r;
 411	int i;
 412
 413	pci_bus_for_each_resource(bus, r, i) {
 414		if (!r)
 415			continue;
 416		if (res->start && resource_contains(r, res)) {
 417
 418			/*
 419			 * If the window is prefetchable but the BAR is
 420			 * not, the allocator made a mistake.
 421			 */
 422			if (r->flags & IORESOURCE_PREFETCH &&
 423			    !(res->flags & IORESOURCE_PREFETCH))
 424				return NULL;
 425
 426			/*
 427			 * If we're below a transparent bridge, there may
 428			 * be both a positively-decoded aperture and a
 429			 * subtractively-decoded region that contain the BAR.
 430			 * We want the positively-decoded one, so this depends
 431			 * on pci_bus_for_each_resource() giving us those
 432			 * first.
 433			 */
 434			return r;
 435		}
 436	}
 437	return NULL;
 438}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 439
 440/**
 441 * pci_wait_for_pending - wait for @mask bit(s) to clear in status word @pos
 442 * @dev: the PCI device to operate on
 443 * @pos: config space offset of status word
 444 * @mask: mask of bit(s) to care about in status word
 445 *
 446 * Return 1 when mask bit(s) in status word clear, 0 otherwise.
 447 */
 448int pci_wait_for_pending(struct pci_dev *dev, int pos, u16 mask)
 449{
 450	int i;
 451
 452	/* Wait for Transaction Pending bit clean */
 453	for (i = 0; i < 4; i++) {
 454		u16 status;
 455		if (i)
 456			msleep((1 << (i - 1)) * 100);
 457
 458		pci_read_config_word(dev, pos, &status);
 459		if (!(status & mask))
 460			return 1;
 461	}
 462
 463	return 0;
 464}
 465
 466/**
 467 * pci_restore_bars - restore a devices BAR values (e.g. after wake-up)
 468 * @dev: PCI device to have its BARs restored
 469 *
 470 * Restore the BAR values for a given device, so as to make it
 471 * accessible by its driver.
 472 */
 473static void
 474pci_restore_bars(struct pci_dev *dev)
 475{
 476	int i;
 477
 478	for (i = 0; i < PCI_BRIDGE_RESOURCES; i++)
 479		pci_update_resource(dev, i);
 480}
 481
 482static struct pci_platform_pm_ops *pci_platform_pm;
 483
 484int pci_set_platform_pm(struct pci_platform_pm_ops *ops)
 485{
 486	if (!ops->is_manageable || !ops->set_state || !ops->choose_state
 487	    || !ops->sleep_wake)
 488		return -EINVAL;
 489	pci_platform_pm = ops;
 490	return 0;
 491}
 492
 493static inline bool platform_pci_power_manageable(struct pci_dev *dev)
 494{
 495	return pci_platform_pm ? pci_platform_pm->is_manageable(dev) : false;
 496}
 497
 498static inline int platform_pci_set_power_state(struct pci_dev *dev,
 499                                                pci_power_t t)
 500{
 501	return pci_platform_pm ? pci_platform_pm->set_state(dev, t) : -ENOSYS;
 502}
 503
 
 
 
 
 
 
 
 
 
 
 
 504static inline pci_power_t platform_pci_choose_state(struct pci_dev *dev)
 505{
 506	return pci_platform_pm ?
 507			pci_platform_pm->choose_state(dev) : PCI_POWER_ERROR;
 508}
 509
 510static inline int platform_pci_sleep_wake(struct pci_dev *dev, bool enable)
 511{
 512	return pci_platform_pm ?
 513			pci_platform_pm->sleep_wake(dev, enable) : -ENODEV;
 514}
 515
 516static inline int platform_pci_run_wake(struct pci_dev *dev, bool enable)
 517{
 518	return pci_platform_pm ?
 519			pci_platform_pm->run_wake(dev, enable) : -ENODEV;
 
 
 
 
 520}
 521
 522/**
 523 * pci_raw_set_power_state - Use PCI PM registers to set the power state of
 524 *                           given PCI device
 525 * @dev: PCI device to handle.
 526 * @state: PCI power state (D0, D1, D2, D3hot) to put the device into.
 527 *
 528 * RETURN VALUE:
 529 * -EINVAL if the requested state is invalid.
 530 * -EIO if device does not support PCI PM or its PM capabilities register has a
 531 * wrong version, or device doesn't support the requested state.
 532 * 0 if device already is in the requested state.
 533 * 0 if device's power state has been successfully changed.
 534 */
 535static int pci_raw_set_power_state(struct pci_dev *dev, pci_power_t state)
 536{
 537	u16 pmcsr;
 538	bool need_restore = false;
 539
 540	/* Check if we're already there */
 541	if (dev->current_state == state)
 542		return 0;
 543
 544	if (!dev->pm_cap)
 545		return -EIO;
 546
 547	if (state < PCI_D0 || state > PCI_D3hot)
 548		return -EINVAL;
 549
 550	/* Validate current state:
 
 551	 * Can enter D0 from any state, but if we can only go deeper
 552	 * to sleep if we're already in a low power state
 553	 */
 554	if (state != PCI_D0 && dev->current_state <= PCI_D3cold
 555	    && dev->current_state > state) {
 556		dev_err(&dev->dev, "invalid power transition "
 557			"(from state %d to %d)\n", dev->current_state, state);
 558		return -EINVAL;
 559	}
 560
 561	/* check if this device supports the desired state */
 562	if ((state == PCI_D1 && !dev->d1_support)
 563	   || (state == PCI_D2 && !dev->d2_support))
 564		return -EIO;
 565
 566	pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
 567
 568	/* If we're (effectively) in D3, force entire word to 0.
 
 569	 * This doesn't affect PME_Status, disables PME_En, and
 570	 * sets PowerState to 0.
 571	 */
 572	switch (dev->current_state) {
 573	case PCI_D0:
 574	case PCI_D1:
 575	case PCI_D2:
 576		pmcsr &= ~PCI_PM_CTRL_STATE_MASK;
 577		pmcsr |= state;
 578		break;
 579	case PCI_D3hot:
 580	case PCI_D3cold:
 581	case PCI_UNKNOWN: /* Boot-up */
 582		if ((pmcsr & PCI_PM_CTRL_STATE_MASK) == PCI_D3hot
 583		 && !(pmcsr & PCI_PM_CTRL_NO_SOFT_RESET))
 584			need_restore = true;
 585		/* Fall-through: force to D0 */
 586	default:
 587		pmcsr = 0;
 588		break;
 589	}
 590
 591	/* enter specified state */
 592	pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr);
 593
 594	/* Mandatory power management transition delays */
 595	/* see PCI PM 1.1 5.6.1 table 18 */
 
 
 596	if (state == PCI_D3hot || dev->current_state == PCI_D3hot)
 597		pci_dev_d3_sleep(dev);
 598	else if (state == PCI_D2 || dev->current_state == PCI_D2)
 599		udelay(PCI_PM_D2_DELAY);
 600
 601	pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
 602	dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
 603	if (dev->current_state != state && printk_ratelimit())
 604		dev_info(&dev->dev, "Refused to change power state, "
 605			"currently in D%d\n", dev->current_state);
 606
 607	/*
 608	 * According to section 5.4.1 of the "PCI BUS POWER MANAGEMENT
 609	 * INTERFACE SPECIFICATION, REV. 1.2", a device transitioning
 610	 * from D3hot to D0 _may_ perform an internal reset, thereby
 611	 * going to "D0 Uninitialized" rather than "D0 Initialized".
 612	 * For example, at least some versions of the 3c905B and the
 613	 * 3c556B exhibit this behaviour.
 614	 *
 615	 * At least some laptop BIOSen (e.g. the Thinkpad T21) leave
 616	 * devices in a D3hot state at boot.  Consequently, we need to
 617	 * restore at least the BARs so that the device will be
 618	 * accessible to its driver.
 619	 */
 620	if (need_restore)
 621		pci_restore_bars(dev);
 622
 623	if (dev->bus->self)
 624		pcie_aspm_pm_state_change(dev->bus->self);
 625
 626	return 0;
 627}
 628
 629/**
 630 * pci_update_current_state - Read PCI power state of given device from its
 631 *                            PCI PM registers and cache it
 632 * @dev: PCI device to handle.
 633 * @state: State to cache in case the device doesn't have the PM capability
 
 
 
 
 
 
 
 634 */
 635void pci_update_current_state(struct pci_dev *dev, pci_power_t state)
 636{
 637	if (dev->pm_cap) {
 
 
 
 638		u16 pmcsr;
 639
 640		/*
 641		 * Configuration space is not accessible for device in
 642		 * D3cold, so just keep or set D3cold for safety
 643		 */
 644		if (dev->current_state == PCI_D3cold)
 645			return;
 646		if (state == PCI_D3cold) {
 647			dev->current_state = PCI_D3cold;
 648			return;
 649		}
 650		pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
 651		dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
 652	} else {
 653		dev->current_state = state;
 654	}
 655}
 656
 657/**
 658 * pci_power_up - Put the given device into D0 forcibly
 659 * @dev: PCI device to power up
 
 
 
 660 */
 661void pci_power_up(struct pci_dev *dev)
 662{
 663	if (platform_pci_power_manageable(dev))
 664		platform_pci_set_power_state(dev, PCI_D0);
 665
 666	pci_raw_set_power_state(dev, PCI_D0);
 667	pci_update_current_state(dev, PCI_D0);
 668}
 669
 670/**
 671 * pci_platform_power_transition - Use platform to change device power state
 672 * @dev: PCI device to handle.
 673 * @state: State to put the device into.
 674 */
 675static int pci_platform_power_transition(struct pci_dev *dev, pci_power_t state)
 676{
 677	int error;
 678
 679	if (platform_pci_power_manageable(dev)) {
 680		error = platform_pci_set_power_state(dev, state);
 681		if (!error)
 682			pci_update_current_state(dev, state);
 683	} else
 684		error = -ENODEV;
 685
 686	if (error && !dev->pm_cap) /* Fall back to PCI_D0 */
 687		dev->current_state = PCI_D0;
 688
 689	return error;
 690}
 691
 692/**
 693 * pci_wakeup - Wake up a PCI device
 694 * @pci_dev: Device to handle.
 695 * @ign: ignored parameter
 696 */
 697static int pci_wakeup(struct pci_dev *pci_dev, void *ign)
 698{
 699	pci_wakeup_event(pci_dev);
 700	pm_request_resume(&pci_dev->dev);
 701	return 0;
 702}
 703
 704/**
 705 * pci_wakeup_bus - Walk given bus and wake up devices on it
 706 * @bus: Top bus of the subtree to walk.
 707 */
 708static void pci_wakeup_bus(struct pci_bus *bus)
 709{
 710	if (bus)
 711		pci_walk_bus(bus, pci_wakeup, NULL);
 712}
 713
 714/**
 715 * __pci_start_power_transition - Start power transition of a PCI device
 716 * @dev: PCI device to handle.
 717 * @state: State to put the device into.
 718 */
 719static void __pci_start_power_transition(struct pci_dev *dev, pci_power_t state)
 720{
 721	if (state == PCI_D0) {
 722		pci_platform_power_transition(dev, PCI_D0);
 723		/*
 724		 * Mandatory power management transition delays, see
 725		 * PCI Express Base Specification Revision 2.0 Section
 726		 * 6.6.1: Conventional Reset.  Do not delay for
 727		 * devices powered on/off by corresponding bridge,
 728		 * because have already delayed for the bridge.
 729		 */
 730		if (dev->runtime_d3cold) {
 731			msleep(dev->d3cold_delay);
 
 732			/*
 733			 * When powering on a bridge from D3cold, the
 734			 * whole hierarchy may be powered on into
 735			 * D0uninitialized state, resume them to give
 736			 * them a chance to suspend again
 737			 */
 738			pci_wakeup_bus(dev->subordinate);
 739		}
 740	}
 741}
 742
 743/**
 744 * __pci_dev_set_current_state - Set current state of a PCI device
 745 * @dev: Device to handle
 746 * @data: pointer to state to be set
 747 */
 748static int __pci_dev_set_current_state(struct pci_dev *dev, void *data)
 749{
 750	pci_power_t state = *(pci_power_t *)data;
 751
 752	dev->current_state = state;
 753	return 0;
 754}
 755
 756/**
 757 * __pci_bus_set_current_state - Walk given bus and set current state of devices
 758 * @bus: Top bus of the subtree to walk.
 759 * @state: state to be set
 760 */
 761static void __pci_bus_set_current_state(struct pci_bus *bus, pci_power_t state)
 762{
 763	if (bus)
 764		pci_walk_bus(bus, __pci_dev_set_current_state, &state);
 765}
 766
 767/**
 768 * __pci_complete_power_transition - Complete power transition of a PCI device
 769 * @dev: PCI device to handle.
 770 * @state: State to put the device into.
 771 *
 772 * This function should not be called directly by device drivers.
 773 */
 774int __pci_complete_power_transition(struct pci_dev *dev, pci_power_t state)
 775{
 776	int ret;
 777
 778	if (state <= PCI_D0)
 779		return -EINVAL;
 780	ret = pci_platform_power_transition(dev, state);
 781	/* Power off the bridge may power off the whole hierarchy */
 782	if (!ret && state == PCI_D3cold)
 783		__pci_bus_set_current_state(dev->subordinate, PCI_D3cold);
 784	return ret;
 785}
 786EXPORT_SYMBOL_GPL(__pci_complete_power_transition);
 787
 788/**
 789 * pci_set_power_state - Set the power state of a PCI device
 790 * @dev: PCI device to handle.
 791 * @state: PCI power state (D0, D1, D2, D3hot) to put the device into.
 792 *
 793 * Transition a device to a new power state, using the platform firmware and/or
 794 * the device's PCI PM registers.
 795 *
 796 * RETURN VALUE:
 797 * -EINVAL if the requested state is invalid.
 798 * -EIO if device does not support PCI PM or its PM capabilities register has a
 799 * wrong version, or device doesn't support the requested state.
 
 800 * 0 if device already is in the requested state.
 
 801 * 0 if device's power state has been successfully changed.
 802 */
 803int pci_set_power_state(struct pci_dev *dev, pci_power_t state)
 804{
 805	int error;
 806
 807	/* bound the state we're entering */
 808	if (state > PCI_D3cold)
 809		state = PCI_D3cold;
 810	else if (state < PCI_D0)
 811		state = PCI_D0;
 812	else if ((state == PCI_D1 || state == PCI_D2) && pci_no_d1d2(dev))
 
 813		/*
 814		 * If the device or the parent bridge do not support PCI PM,
 815		 * ignore the request if we're doing anything other than putting
 816		 * it into D0 (which would only happen on boot).
 
 817		 */
 818		return 0;
 819
 820	/* Check if we're already there */
 821	if (dev->current_state == state)
 822		return 0;
 823
 824	__pci_start_power_transition(dev, state);
 825
 826	/* This device is quirked not to be put into D3, so
 827	   don't put it in D3 */
 
 
 828	if (state >= PCI_D3hot && (dev->dev_flags & PCI_DEV_FLAGS_NO_D3))
 829		return 0;
 830
 831	/*
 832	 * To put device in D3cold, we put device into D3hot in native
 833	 * way, then put device into D3cold with platform ops
 834	 */
 835	error = pci_raw_set_power_state(dev, state > PCI_D3hot ?
 836					PCI_D3hot : state);
 837
 838	if (!__pci_complete_power_transition(dev, state))
 839		error = 0;
 840	/*
 841	 * When aspm_policy is "powersave" this call ensures
 842	 * that ASPM is configured.
 843	 */
 844	if (!error && dev->bus->self)
 845		pcie_aspm_powersave_config_link(dev->bus->self);
 846
 847	return error;
 848}
 
 
 
 
 
 
 
 
 
 
 
 
 849
 850/**
 851 * pci_choose_state - Choose the power state of a PCI device
 852 * @dev: PCI device to be suspended
 853 * @state: target sleep state for the whole system. This is the value
 854 *	that is passed to suspend() function.
 855 *
 856 * Returns PCI power state suitable for given device and given system
 857 * message.
 858 */
 859
 860pci_power_t pci_choose_state(struct pci_dev *dev, pm_message_t state)
 861{
 862	pci_power_t ret;
 863
 864	if (!dev->pm_cap)
 865		return PCI_D0;
 866
 867	ret = platform_pci_choose_state(dev);
 868	if (ret != PCI_POWER_ERROR)
 869		return ret;
 870
 871	switch (state.event) {
 872	case PM_EVENT_ON:
 873		return PCI_D0;
 874	case PM_EVENT_FREEZE:
 875	case PM_EVENT_PRETHAW:
 876		/* REVISIT both freeze and pre-thaw "should" use D0 */
 877	case PM_EVENT_SUSPEND:
 878	case PM_EVENT_HIBERNATE:
 879		return PCI_D3hot;
 880	default:
 881		dev_info(&dev->dev, "unrecognized suspend event %d\n",
 882			 state.event);
 883		BUG();
 884	}
 885	return PCI_D0;
 886}
 887
 888EXPORT_SYMBOL(pci_choose_state);
 889
 890#define PCI_EXP_SAVE_REGS	7
 891
 892
 893static struct pci_cap_saved_state *_pci_find_saved_cap(struct pci_dev *pci_dev,
 894						       u16 cap, bool extended)
 895{
 896	struct pci_cap_saved_state *tmp;
 897
 898	hlist_for_each_entry(tmp, &pci_dev->saved_cap_space, next) {
 899		if (tmp->cap.cap_extended == extended && tmp->cap.cap_nr == cap)
 900			return tmp;
 901	}
 902	return NULL;
 903}
 904
 905struct pci_cap_saved_state *pci_find_saved_cap(struct pci_dev *dev, char cap)
 906{
 907	return _pci_find_saved_cap(dev, cap, false);
 908}
 909
 910struct pci_cap_saved_state *pci_find_saved_ext_cap(struct pci_dev *dev, u16 cap)
 911{
 912	return _pci_find_saved_cap(dev, cap, true);
 913}
 914
 915static int pci_save_pcie_state(struct pci_dev *dev)
 916{
 917	int i = 0;
 918	struct pci_cap_saved_state *save_state;
 919	u16 *cap;
 920
 921	if (!pci_is_pcie(dev))
 922		return 0;
 923
 924	save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
 925	if (!save_state) {
 926		dev_err(&dev->dev, "buffer not found in %s\n", __func__);
 927		return -ENOMEM;
 928	}
 929
 930	cap = (u16 *)&save_state->cap.data[0];
 931	pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &cap[i++]);
 932	pcie_capability_read_word(dev, PCI_EXP_LNKCTL, &cap[i++]);
 933	pcie_capability_read_word(dev, PCI_EXP_SLTCTL, &cap[i++]);
 934	pcie_capability_read_word(dev, PCI_EXP_RTCTL,  &cap[i++]);
 935	pcie_capability_read_word(dev, PCI_EXP_DEVCTL2, &cap[i++]);
 936	pcie_capability_read_word(dev, PCI_EXP_LNKCTL2, &cap[i++]);
 937	pcie_capability_read_word(dev, PCI_EXP_SLTCTL2, &cap[i++]);
 938
 939	return 0;
 940}
 941
 942static void pci_restore_pcie_state(struct pci_dev *dev)
 943{
 944	int i = 0;
 945	struct pci_cap_saved_state *save_state;
 946	u16 *cap;
 947
 948	save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
 949	if (!save_state)
 950		return;
 951
 952	cap = (u16 *)&save_state->cap.data[0];
 953	pcie_capability_write_word(dev, PCI_EXP_DEVCTL, cap[i++]);
 954	pcie_capability_write_word(dev, PCI_EXP_LNKCTL, cap[i++]);
 955	pcie_capability_write_word(dev, PCI_EXP_SLTCTL, cap[i++]);
 956	pcie_capability_write_word(dev, PCI_EXP_RTCTL, cap[i++]);
 957	pcie_capability_write_word(dev, PCI_EXP_DEVCTL2, cap[i++]);
 958	pcie_capability_write_word(dev, PCI_EXP_LNKCTL2, cap[i++]);
 959	pcie_capability_write_word(dev, PCI_EXP_SLTCTL2, cap[i++]);
 960}
 961
 962
 963static int pci_save_pcix_state(struct pci_dev *dev)
 964{
 965	int pos;
 966	struct pci_cap_saved_state *save_state;
 967
 968	pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
 969	if (pos <= 0)
 970		return 0;
 971
 972	save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX);
 973	if (!save_state) {
 974		dev_err(&dev->dev, "buffer not found in %s\n", __func__);
 975		return -ENOMEM;
 976	}
 977
 978	pci_read_config_word(dev, pos + PCI_X_CMD,
 979			     (u16 *)save_state->cap.data);
 980
 981	return 0;
 982}
 983
 984static void pci_restore_pcix_state(struct pci_dev *dev)
 985{
 986	int i = 0, pos;
 987	struct pci_cap_saved_state *save_state;
 988	u16 *cap;
 989
 990	save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX);
 991	pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
 992	if (!save_state || pos <= 0)
 993		return;
 994	cap = (u16 *)&save_state->cap.data[0];
 995
 996	pci_write_config_word(dev, pos + PCI_X_CMD, cap[i++]);
 997}
 998
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 999
1000/**
1001 * pci_save_state - save the PCI configuration space of a device before suspending
1002 * @dev: - PCI device that we're dealing with
 
1003 */
1004int
1005pci_save_state(struct pci_dev *dev)
1006{
1007	int i;
1008	/* XXX: 100% dword access ok here? */
1009	for (i = 0; i < 16; i++)
1010		pci_read_config_dword(dev, i * 4, &dev->saved_config_space[i]);
1011	dev->state_saved = true;
1012	if ((i = pci_save_pcie_state(dev)) != 0)
 
 
1013		return i;
1014	if ((i = pci_save_pcix_state(dev)) != 0)
 
 
1015		return i;
1016	if ((i = pci_save_vc_state(dev)) != 0)
1017		return i;
1018	return 0;
 
1019}
 
1020
1021static void pci_restore_config_dword(struct pci_dev *pdev, int offset,
1022				     u32 saved_val, int retry)
1023{
1024	u32 val;
1025
1026	pci_read_config_dword(pdev, offset, &val);
1027	if (val == saved_val)
1028		return;
1029
1030	for (;;) {
1031		dev_dbg(&pdev->dev, "restoring config space at offset "
1032			"%#x (was %#x, writing %#x)\n", offset, val, saved_val);
1033		pci_write_config_dword(pdev, offset, saved_val);
1034		if (retry-- <= 0)
1035			return;
1036
1037		pci_read_config_dword(pdev, offset, &val);
1038		if (val == saved_val)
1039			return;
1040
1041		mdelay(1);
1042	}
1043}
1044
1045static void pci_restore_config_space_range(struct pci_dev *pdev,
1046					   int start, int end, int retry)
 
1047{
1048	int index;
1049
1050	for (index = end; index >= start; index--)
1051		pci_restore_config_dword(pdev, 4 * index,
1052					 pdev->saved_config_space[index],
1053					 retry);
1054}
1055
1056static void pci_restore_config_space(struct pci_dev *pdev)
1057{
1058	if (pdev->hdr_type == PCI_HEADER_TYPE_NORMAL) {
1059		pci_restore_config_space_range(pdev, 10, 15, 0);
1060		/* Restore BARs before the command register. */
1061		pci_restore_config_space_range(pdev, 4, 9, 10);
1062		pci_restore_config_space_range(pdev, 0, 3, 0);
 
 
 
 
 
 
 
 
 
 
1063	} else {
1064		pci_restore_config_space_range(pdev, 0, 15, 0);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1065	}
1066}
1067
1068/**
1069 * pci_restore_state - Restore the saved state of a PCI device
1070 * @dev: - PCI device that we're dealing with
1071 */
1072void pci_restore_state(struct pci_dev *dev)
1073{
1074	if (!dev->state_saved)
1075		return;
1076
1077	/* PCI Express register must be restored first */
 
 
 
 
 
1078	pci_restore_pcie_state(dev);
 
 
1079	pci_restore_ats_state(dev);
1080	pci_restore_vc_state(dev);
 
 
 
 
1081
1082	pci_restore_config_space(dev);
1083
1084	pci_restore_pcix_state(dev);
1085	pci_restore_msi_state(dev);
 
 
 
1086	pci_restore_iov_state(dev);
1087
1088	dev->state_saved = false;
1089}
 
1090
1091struct pci_saved_state {
1092	u32 config_space[16];
1093	struct pci_cap_saved_data cap[0];
1094};
1095
1096/**
1097 * pci_store_saved_state - Allocate and return an opaque struct containing
1098 *			   the device saved state.
1099 * @dev: PCI device that we're dealing with
1100 *
1101 * Return NULL if no state or error.
1102 */
1103struct pci_saved_state *pci_store_saved_state(struct pci_dev *dev)
1104{
1105	struct pci_saved_state *state;
1106	struct pci_cap_saved_state *tmp;
1107	struct pci_cap_saved_data *cap;
1108	size_t size;
1109
1110	if (!dev->state_saved)
1111		return NULL;
1112
1113	size = sizeof(*state) + sizeof(struct pci_cap_saved_data);
1114
1115	hlist_for_each_entry(tmp, &dev->saved_cap_space, next)
1116		size += sizeof(struct pci_cap_saved_data) + tmp->cap.size;
1117
1118	state = kzalloc(size, GFP_KERNEL);
1119	if (!state)
1120		return NULL;
1121
1122	memcpy(state->config_space, dev->saved_config_space,
1123	       sizeof(state->config_space));
1124
1125	cap = state->cap;
1126	hlist_for_each_entry(tmp, &dev->saved_cap_space, next) {
1127		size_t len = sizeof(struct pci_cap_saved_data) + tmp->cap.size;
1128		memcpy(cap, &tmp->cap, len);
1129		cap = (struct pci_cap_saved_data *)((u8 *)cap + len);
1130	}
1131	/* Empty cap_save terminates list */
1132
1133	return state;
1134}
1135EXPORT_SYMBOL_GPL(pci_store_saved_state);
1136
1137/**
1138 * pci_load_saved_state - Reload the provided save state into struct pci_dev.
1139 * @dev: PCI device that we're dealing with
1140 * @state: Saved state returned from pci_store_saved_state()
1141 */
1142static int pci_load_saved_state(struct pci_dev *dev,
1143				struct pci_saved_state *state)
1144{
1145	struct pci_cap_saved_data *cap;
1146
1147	dev->state_saved = false;
1148
1149	if (!state)
1150		return 0;
1151
1152	memcpy(dev->saved_config_space, state->config_space,
1153	       sizeof(state->config_space));
1154
1155	cap = state->cap;
1156	while (cap->size) {
1157		struct pci_cap_saved_state *tmp;
1158
1159		tmp = _pci_find_saved_cap(dev, cap->cap_nr, cap->cap_extended);
1160		if (!tmp || tmp->cap.size != cap->size)
1161			return -EINVAL;
1162
1163		memcpy(tmp->cap.data, cap->data, tmp->cap.size);
1164		cap = (struct pci_cap_saved_data *)((u8 *)cap +
1165		       sizeof(struct pci_cap_saved_data) + cap->size);
1166	}
1167
1168	dev->state_saved = true;
1169	return 0;
1170}
 
1171
1172/**
1173 * pci_load_and_free_saved_state - Reload the save state pointed to by state,
1174 *				   and free the memory allocated for it.
1175 * @dev: PCI device that we're dealing with
1176 * @state: Pointer to saved state returned from pci_store_saved_state()
1177 */
1178int pci_load_and_free_saved_state(struct pci_dev *dev,
1179				  struct pci_saved_state **state)
1180{
1181	int ret = pci_load_saved_state(dev, *state);
1182	kfree(*state);
1183	*state = NULL;
1184	return ret;
1185}
1186EXPORT_SYMBOL_GPL(pci_load_and_free_saved_state);
1187
1188int __weak pcibios_enable_device(struct pci_dev *dev, int bars)
1189{
1190	return pci_enable_resources(dev, bars);
1191}
1192
1193static int do_pci_enable_device(struct pci_dev *dev, int bars)
1194{
1195	int err;
 
1196	u16 cmd;
1197	u8 pin;
1198
1199	err = pci_set_power_state(dev, PCI_D0);
1200	if (err < 0 && err != -EIO)
1201		return err;
 
 
 
 
 
1202	err = pcibios_enable_device(dev, bars);
1203	if (err < 0)
1204		return err;
1205	pci_fixup_device(pci_fixup_enable, dev);
1206
1207	if (dev->msi_enabled || dev->msix_enabled)
1208		return 0;
1209
1210	pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
1211	if (pin) {
1212		pci_read_config_word(dev, PCI_COMMAND, &cmd);
1213		if (cmd & PCI_COMMAND_INTX_DISABLE)
1214			pci_write_config_word(dev, PCI_COMMAND,
1215					      cmd & ~PCI_COMMAND_INTX_DISABLE);
1216	}
1217
1218	return 0;
1219}
1220
1221/**
1222 * pci_reenable_device - Resume abandoned device
1223 * @dev: PCI device to be resumed
1224 *
1225 *  Note this function is a backend of pci_default_resume and is not supposed
1226 *  to be called by normal code, write proper resume handler and use it instead.
1227 */
1228int pci_reenable_device(struct pci_dev *dev)
1229{
1230	if (pci_is_enabled(dev))
1231		return do_pci_enable_device(dev, (1 << PCI_NUM_RESOURCES) - 1);
1232	return 0;
1233}
 
1234
1235static void pci_enable_bridge(struct pci_dev *dev)
1236{
1237	struct pci_dev *bridge;
1238	int retval;
1239
1240	bridge = pci_upstream_bridge(dev);
1241	if (bridge)
1242		pci_enable_bridge(bridge);
1243
1244	if (pci_is_enabled(dev)) {
1245		if (!dev->is_busmaster)
1246			pci_set_master(dev);
1247		return;
1248	}
1249
1250	retval = pci_enable_device(dev);
1251	if (retval)
1252		dev_err(&dev->dev, "Error enabling bridge (%d), continuing\n",
1253			retval);
1254	pci_set_master(dev);
1255}
1256
1257static int pci_enable_device_flags(struct pci_dev *dev, unsigned long flags)
1258{
1259	struct pci_dev *bridge;
1260	int err;
1261	int i, bars = 0;
1262
1263	/*
1264	 * Power state could be unknown at this point, either due to a fresh
1265	 * boot or a device removal call.  So get the current power state
1266	 * so that things like MSI message writing will behave as expected
1267	 * (e.g. if the device really is in D0 at enable time).
1268	 */
1269	if (dev->pm_cap) {
1270		u16 pmcsr;
1271		pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
1272		dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
1273	}
1274
1275	if (atomic_inc_return(&dev->enable_cnt) > 1)
1276		return 0;		/* already enabled */
1277
1278	bridge = pci_upstream_bridge(dev);
1279	if (bridge)
1280		pci_enable_bridge(bridge);
1281
1282	/* only skip sriov related */
1283	for (i = 0; i <= PCI_ROM_RESOURCE; i++)
1284		if (dev->resource[i].flags & flags)
1285			bars |= (1 << i);
1286	for (i = PCI_BRIDGE_RESOURCES; i < DEVICE_COUNT_RESOURCE; i++)
1287		if (dev->resource[i].flags & flags)
1288			bars |= (1 << i);
1289
1290	err = do_pci_enable_device(dev, bars);
1291	if (err < 0)
1292		atomic_dec(&dev->enable_cnt);
1293	return err;
1294}
1295
1296/**
1297 * pci_enable_device_io - Initialize a device for use with IO space
1298 * @dev: PCI device to be initialized
1299 *
1300 *  Initialize device before it's used by a driver. Ask low-level code
1301 *  to enable I/O resources. Wake up the device if it was suspended.
1302 *  Beware, this function can fail.
1303 */
1304int pci_enable_device_io(struct pci_dev *dev)
1305{
1306	return pci_enable_device_flags(dev, IORESOURCE_IO);
1307}
 
1308
1309/**
1310 * pci_enable_device_mem - Initialize a device for use with Memory space
1311 * @dev: PCI device to be initialized
1312 *
1313 *  Initialize device before it's used by a driver. Ask low-level code
1314 *  to enable Memory resources. Wake up the device if it was suspended.
1315 *  Beware, this function can fail.
1316 */
1317int pci_enable_device_mem(struct pci_dev *dev)
1318{
1319	return pci_enable_device_flags(dev, IORESOURCE_MEM);
1320}
 
1321
1322/**
1323 * pci_enable_device - Initialize device before it's used by a driver.
1324 * @dev: PCI device to be initialized
1325 *
1326 *  Initialize device before it's used by a driver. Ask low-level code
1327 *  to enable I/O and memory. Wake up the device if it was suspended.
1328 *  Beware, this function can fail.
1329 *
1330 *  Note we don't actually enable the device many times if we call
1331 *  this function repeatedly (we just increment the count).
1332 */
1333int pci_enable_device(struct pci_dev *dev)
1334{
1335	return pci_enable_device_flags(dev, IORESOURCE_MEM | IORESOURCE_IO);
1336}
 
1337
1338/*
1339 * Managed PCI resources.  This manages device on/off, intx/msi/msix
1340 * on/off and BAR regions.  pci_dev itself records msi/msix status, so
1341 * there's no need to track it separately.  pci_devres is initialized
1342 * when a device is enabled using managed PCI device enable interface.
1343 */
1344struct pci_devres {
1345	unsigned int enabled:1;
1346	unsigned int pinned:1;
1347	unsigned int orig_intx:1;
1348	unsigned int restore_intx:1;
 
1349	u32 region_mask;
1350};
1351
1352static void pcim_release(struct device *gendev, void *res)
1353{
1354	struct pci_dev *dev = container_of(gendev, struct pci_dev, dev);
1355	struct pci_devres *this = res;
1356	int i;
1357
1358	if (dev->msi_enabled)
1359		pci_disable_msi(dev);
1360	if (dev->msix_enabled)
1361		pci_disable_msix(dev);
1362
1363	for (i = 0; i < DEVICE_COUNT_RESOURCE; i++)
1364		if (this->region_mask & (1 << i))
1365			pci_release_region(dev, i);
1366
 
 
 
1367	if (this->restore_intx)
1368		pci_intx(dev, this->orig_intx);
1369
1370	if (this->enabled && !this->pinned)
1371		pci_disable_device(dev);
1372}
1373
1374static struct pci_devres * get_pci_dr(struct pci_dev *pdev)
1375{
1376	struct pci_devres *dr, *new_dr;
1377
1378	dr = devres_find(&pdev->dev, pcim_release, NULL, NULL);
1379	if (dr)
1380		return dr;
1381
1382	new_dr = devres_alloc(pcim_release, sizeof(*new_dr), GFP_KERNEL);
1383	if (!new_dr)
1384		return NULL;
1385	return devres_get(&pdev->dev, new_dr, NULL, NULL);
1386}
1387
1388static struct pci_devres * find_pci_dr(struct pci_dev *pdev)
1389{
1390	if (pci_is_managed(pdev))
1391		return devres_find(&pdev->dev, pcim_release, NULL, NULL);
1392	return NULL;
1393}
1394
1395/**
1396 * pcim_enable_device - Managed pci_enable_device()
1397 * @pdev: PCI device to be initialized
1398 *
1399 * Managed pci_enable_device().
1400 */
1401int pcim_enable_device(struct pci_dev *pdev)
1402{
1403	struct pci_devres *dr;
1404	int rc;
1405
1406	dr = get_pci_dr(pdev);
1407	if (unlikely(!dr))
1408		return -ENOMEM;
1409	if (dr->enabled)
1410		return 0;
1411
1412	rc = pci_enable_device(pdev);
1413	if (!rc) {
1414		pdev->is_managed = 1;
1415		dr->enabled = 1;
1416	}
1417	return rc;
1418}
 
1419
1420/**
1421 * pcim_pin_device - Pin managed PCI device
1422 * @pdev: PCI device to pin
1423 *
1424 * Pin managed PCI device @pdev.  Pinned device won't be disabled on
1425 * driver detach.  @pdev must have been enabled with
1426 * pcim_enable_device().
1427 */
1428void pcim_pin_device(struct pci_dev *pdev)
1429{
1430	struct pci_devres *dr;
1431
1432	dr = find_pci_dr(pdev);
1433	WARN_ON(!dr || !dr->enabled);
1434	if (dr)
1435		dr->pinned = 1;
1436}
 
1437
1438/*
1439 * pcibios_add_device - provide arch specific hooks when adding device dev
1440 * @dev: the PCI device being added
1441 *
1442 * Permits the platform to provide architecture specific functionality when
1443 * devices are added. This is the default implementation. Architecture
1444 * implementations can override this.
1445 */
1446int __weak pcibios_add_device (struct pci_dev *dev)
1447{
1448	return 0;
1449}
1450
1451/**
1452 * pcibios_release_device - provide arch specific hooks when releasing device dev
 
1453 * @dev: the PCI device being released
1454 *
1455 * Permits the platform to provide architecture specific functionality when
1456 * devices are released. This is the default implementation. Architecture
1457 * implementations can override this.
1458 */
1459void __weak pcibios_release_device(struct pci_dev *dev) {}
1460
1461/**
1462 * pcibios_disable_device - disable arch specific PCI resources for device dev
1463 * @dev: the PCI device to disable
1464 *
1465 * Disables architecture specific PCI resources for the device. This
1466 * is the default implementation. Architecture implementations can
1467 * override this.
1468 */
1469void __weak pcibios_disable_device (struct pci_dev *dev) {}
 
 
 
 
 
 
 
 
 
 
 
1470
1471static void do_pci_disable_device(struct pci_dev *dev)
1472{
1473	u16 pci_command;
1474
1475	pci_read_config_word(dev, PCI_COMMAND, &pci_command);
1476	if (pci_command & PCI_COMMAND_MASTER) {
1477		pci_command &= ~PCI_COMMAND_MASTER;
1478		pci_write_config_word(dev, PCI_COMMAND, pci_command);
1479	}
1480
1481	pcibios_disable_device(dev);
1482}
1483
1484/**
1485 * pci_disable_enabled_device - Disable device without updating enable_cnt
1486 * @dev: PCI device to disable
1487 *
1488 * NOTE: This function is a backend of PCI power management routines and is
1489 * not supposed to be called drivers.
1490 */
1491void pci_disable_enabled_device(struct pci_dev *dev)
1492{
1493	if (pci_is_enabled(dev))
1494		do_pci_disable_device(dev);
1495}
1496
1497/**
1498 * pci_disable_device - Disable PCI device after use
1499 * @dev: PCI device to be disabled
1500 *
1501 * Signal to the system that the PCI device is not in use by the system
1502 * anymore.  This only involves disabling PCI bus-mastering, if active.
1503 *
1504 * Note we don't actually disable the device until all callers of
1505 * pci_enable_device() have called pci_disable_device().
1506 */
1507void
1508pci_disable_device(struct pci_dev *dev)
1509{
1510	struct pci_devres *dr;
1511
1512	dr = find_pci_dr(dev);
1513	if (dr)
1514		dr->enabled = 0;
1515
1516	dev_WARN_ONCE(&dev->dev, atomic_read(&dev->enable_cnt) <= 0,
1517		      "disabling already-disabled device");
1518
1519	if (atomic_dec_return(&dev->enable_cnt) != 0)
1520		return;
1521
1522	do_pci_disable_device(dev);
1523
1524	dev->is_busmaster = 0;
1525}
 
1526
1527/**
1528 * pcibios_set_pcie_reset_state - set reset state for device dev
1529 * @dev: the PCIe device reset
1530 * @state: Reset state to enter into
1531 *
1532 *
1533 * Sets the PCIe reset state for the device. This is the default
1534 * implementation. Architecture implementations can override this.
1535 */
1536int __weak pcibios_set_pcie_reset_state(struct pci_dev *dev,
1537					enum pcie_reset_state state)
1538{
1539	return -EINVAL;
1540}
1541
1542/**
1543 * pci_set_pcie_reset_state - set reset state for device dev
1544 * @dev: the PCIe device reset
1545 * @state: Reset state to enter into
1546 *
1547 *
1548 * Sets the PCI reset state for the device.
1549 */
1550int pci_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state)
1551{
1552	return pcibios_set_pcie_reset_state(dev, state);
1553}
 
 
 
 
 
 
 
 
 
 
1554
1555/**
1556 * pci_check_pme_status - Check if given device has generated PME.
1557 * @dev: Device to check.
1558 *
1559 * Check the PME status of the device and if set, clear it and clear PME enable
1560 * (if set).  Return 'true' if PME status and PME enable were both set or
1561 * 'false' otherwise.
1562 */
1563bool pci_check_pme_status(struct pci_dev *dev)
1564{
1565	int pmcsr_pos;
1566	u16 pmcsr;
1567	bool ret = false;
1568
1569	if (!dev->pm_cap)
1570		return false;
1571
1572	pmcsr_pos = dev->pm_cap + PCI_PM_CTRL;
1573	pci_read_config_word(dev, pmcsr_pos, &pmcsr);
1574	if (!(pmcsr & PCI_PM_CTRL_PME_STATUS))
1575		return false;
1576
1577	/* Clear PME status. */
1578	pmcsr |= PCI_PM_CTRL_PME_STATUS;
1579	if (pmcsr & PCI_PM_CTRL_PME_ENABLE) {
1580		/* Disable PME to avoid interrupt flood. */
1581		pmcsr &= ~PCI_PM_CTRL_PME_ENABLE;
1582		ret = true;
1583	}
1584
1585	pci_write_config_word(dev, pmcsr_pos, pmcsr);
1586
1587	return ret;
1588}
1589
1590/**
1591 * pci_pme_wakeup - Wake up a PCI device if its PME Status bit is set.
1592 * @dev: Device to handle.
1593 * @pme_poll_reset: Whether or not to reset the device's pme_poll flag.
1594 *
1595 * Check if @dev has generated PME and queue a resume request for it in that
1596 * case.
1597 */
1598static int pci_pme_wakeup(struct pci_dev *dev, void *pme_poll_reset)
1599{
1600	if (pme_poll_reset && dev->pme_poll)
1601		dev->pme_poll = false;
1602
1603	if (pci_check_pme_status(dev)) {
1604		pci_wakeup_event(dev);
1605		pm_request_resume(&dev->dev);
1606	}
1607	return 0;
1608}
1609
1610/**
1611 * pci_pme_wakeup_bus - Walk given bus and wake up devices on it, if necessary.
1612 * @bus: Top bus of the subtree to walk.
1613 */
1614void pci_pme_wakeup_bus(struct pci_bus *bus)
1615{
1616	if (bus)
1617		pci_walk_bus(bus, pci_pme_wakeup, (void *)true);
1618}
1619
1620
1621/**
1622 * pci_pme_capable - check the capability of PCI device to generate PME#
1623 * @dev: PCI device to handle.
1624 * @state: PCI state from which device will issue PME#.
1625 */
1626bool pci_pme_capable(struct pci_dev *dev, pci_power_t state)
1627{
1628	if (!dev->pm_cap)
1629		return false;
1630
1631	return !!(dev->pme_support & (1 << state));
1632}
 
1633
1634static void pci_pme_list_scan(struct work_struct *work)
1635{
1636	struct pci_pme_device *pme_dev, *n;
1637
1638	mutex_lock(&pci_pme_list_mutex);
1639	list_for_each_entry_safe(pme_dev, n, &pci_pme_list, list) {
1640		if (pme_dev->dev->pme_poll) {
1641			struct pci_dev *bridge;
1642
1643			bridge = pme_dev->dev->bus->self;
1644			/*
1645			 * If bridge is in low power state, the
1646			 * configuration space of subordinate devices
1647			 * may be not accessible
1648			 */
1649			if (bridge && bridge->current_state != PCI_D0)
1650				continue;
 
 
 
 
 
 
 
1651			pci_pme_wakeup(pme_dev->dev, NULL);
1652		} else {
1653			list_del(&pme_dev->list);
1654			kfree(pme_dev);
1655		}
1656	}
1657	if (!list_empty(&pci_pme_list))
1658		schedule_delayed_work(&pci_pme_work,
1659				      msecs_to_jiffies(PME_TIMEOUT));
1660	mutex_unlock(&pci_pme_list_mutex);
1661}
1662
1663/**
1664 * pci_pme_active - enable or disable PCI device's PME# function
1665 * @dev: PCI device to handle.
1666 * @enable: 'true' to enable PME# generation; 'false' to disable it.
1667 *
1668 * The caller must verify that the device is capable of generating PME# before
1669 * calling this function with @enable equal to 'true'.
1670 */
1671void pci_pme_active(struct pci_dev *dev, bool enable)
1672{
1673	u16 pmcsr;
1674
1675	if (!dev->pme_support)
1676		return;
1677
1678	pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
1679	/* Clear PME_Status by writing 1 to it and enable PME# */
1680	pmcsr |= PCI_PM_CTRL_PME_STATUS | PCI_PM_CTRL_PME_ENABLE;
1681	if (!enable)
1682		pmcsr &= ~PCI_PM_CTRL_PME_ENABLE;
1683
1684	pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1685
1686	/*
1687	 * PCI (as opposed to PCIe) PME requires that the device have
1688	 * its PME# line hooked up correctly. Not all hardware vendors
1689	 * do this, so the PME never gets delivered and the device
1690	 * remains asleep. The easiest way around this is to
1691	 * periodically walk the list of suspended devices and check
1692	 * whether any have their PME flag set. The assumption is that
1693	 * we'll wake up often enough anyway that this won't be a huge
1694	 * hit, and the power savings from the devices will still be a
1695	 * win.
1696	 *
1697	 * Although PCIe uses in-band PME message instead of PME# line
1698	 * to report PME, PME does not work for some PCIe devices in
1699	 * reality.  For example, there are devices that set their PME
1700	 * status bits, but don't really bother to send a PME message;
1701	 * there are PCI Express Root Ports that don't bother to
1702	 * trigger interrupts when they receive PME messages from the
1703	 * devices below.  So PME poll is used for PCIe devices too.
1704	 */
1705
1706	if (dev->pme_poll) {
1707		struct pci_pme_device *pme_dev;
1708		if (enable) {
1709			pme_dev = kmalloc(sizeof(struct pci_pme_device),
1710					  GFP_KERNEL);
1711			if (!pme_dev) {
1712				dev_warn(&dev->dev, "can't enable PME#\n");
1713				return;
1714			}
1715			pme_dev->dev = dev;
1716			mutex_lock(&pci_pme_list_mutex);
1717			list_add(&pme_dev->list, &pci_pme_list);
1718			if (list_is_singular(&pci_pme_list))
1719				schedule_delayed_work(&pci_pme_work,
1720						      msecs_to_jiffies(PME_TIMEOUT));
 
1721			mutex_unlock(&pci_pme_list_mutex);
1722		} else {
1723			mutex_lock(&pci_pme_list_mutex);
1724			list_for_each_entry(pme_dev, &pci_pme_list, list) {
1725				if (pme_dev->dev == dev) {
1726					list_del(&pme_dev->list);
1727					kfree(pme_dev);
1728					break;
1729				}
1730			}
1731			mutex_unlock(&pci_pme_list_mutex);
1732		}
1733	}
1734
1735	dev_dbg(&dev->dev, "PME# %s\n", enable ? "enabled" : "disabled");
1736}
 
1737
1738/**
1739 * __pci_enable_wake - enable PCI device as wakeup event source
1740 * @dev: PCI device affected
1741 * @state: PCI state from which device will issue wakeup events
1742 * @runtime: True if the events are to be generated at run time
1743 * @enable: True to enable event generation; false to disable
1744 *
1745 * This enables the device as a wakeup event source, or disables it.
1746 * When such events involves platform-specific hooks, those hooks are
1747 * called automatically by this routine.
1748 *
1749 * Devices with legacy power management (no standard PCI PM capabilities)
1750 * always require such platform hooks.
1751 *
1752 * RETURN VALUE:
1753 * 0 is returned on success
1754 * -EINVAL is returned if device is not supposed to wake up the system
1755 * Error code depending on the platform is returned if both the platform and
1756 * the native mechanism fail to enable the generation of wake-up events
1757 */
1758int __pci_enable_wake(struct pci_dev *dev, pci_power_t state,
1759		      bool runtime, bool enable)
1760{
1761	int ret = 0;
1762
1763	if (enable && !runtime && !device_may_wakeup(&dev->dev))
1764		return -EINVAL;
 
 
 
 
 
 
 
1765
1766	/* Don't do the same thing twice in a row for one device. */
1767	if (!!enable == !!dev->wakeup_prepared)
1768		return 0;
1769
1770	/*
1771	 * According to "PCI System Architecture" 4th ed. by Tom Shanley & Don
1772	 * Anderson we should be doing PME# wake enable followed by ACPI wake
1773	 * enable.  To disable wake-up we call the platform first, for symmetry.
1774	 */
1775
1776	if (enable) {
1777		int error;
1778
1779		if (pci_pme_capable(dev, state))
1780			pci_pme_active(dev, true);
1781		else
1782			ret = 1;
1783		error = runtime ? platform_pci_run_wake(dev, true) :
1784					platform_pci_sleep_wake(dev, true);
1785		if (ret)
1786			ret = error;
1787		if (!ret)
1788			dev->wakeup_prepared = true;
1789	} else {
1790		if (runtime)
1791			platform_pci_run_wake(dev, false);
1792		else
1793			platform_pci_sleep_wake(dev, false);
1794		pci_pme_active(dev, false);
1795		dev->wakeup_prepared = false;
1796	}
1797
1798	return ret;
1799}
1800EXPORT_SYMBOL(__pci_enable_wake);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1801
1802/**
1803 * pci_wake_from_d3 - enable/disable device to wake up from D3_hot or D3_cold
1804 * @dev: PCI device to prepare
1805 * @enable: True to enable wake-up event generation; false to disable
1806 *
1807 * Many drivers want the device to wake up the system from D3_hot or D3_cold
1808 * and this function allows them to set that up cleanly - pci_enable_wake()
1809 * should not be called twice in a row to enable wake-up due to PCI PM vs ACPI
1810 * ordering constraints.
1811 *
1812 * This function only returns error code if the device is not capable of
1813 * generating PME# from both D3_hot and D3_cold, and the platform is unable to
1814 * enable wake-up power for it.
1815 */
1816int pci_wake_from_d3(struct pci_dev *dev, bool enable)
1817{
1818	return pci_pme_capable(dev, PCI_D3cold) ?
1819			pci_enable_wake(dev, PCI_D3cold, enable) :
1820			pci_enable_wake(dev, PCI_D3hot, enable);
1821}
 
1822
1823/**
1824 * pci_target_state - find an appropriate low power state for a given PCI dev
1825 * @dev: PCI device
 
1826 *
1827 * Use underlying platform code to find a supported low power state for @dev.
1828 * If the platform can't manage @dev, return the deepest state from which it
1829 * can generate wake events, based on any available PME info.
1830 */
1831static pci_power_t pci_target_state(struct pci_dev *dev)
1832{
1833	pci_power_t target_state = PCI_D3hot;
1834
1835	if (platform_pci_power_manageable(dev)) {
1836		/*
1837		 * Call the platform to choose the target state of the device
1838		 * and enable wake-up from this state if supported.
1839		 */
1840		pci_power_t state = platform_pci_choose_state(dev);
1841
1842		switch (state) {
1843		case PCI_POWER_ERROR:
1844		case PCI_UNKNOWN:
1845			break;
1846		case PCI_D1:
1847		case PCI_D2:
1848			if (pci_no_d1d2(dev))
1849				break;
 
1850		default:
1851			target_state = state;
1852		}
1853	} else if (!dev->pm_cap) {
 
 
 
 
1854		target_state = PCI_D0;
1855	} else if (device_may_wakeup(&dev->dev)) {
 
 
 
 
 
 
 
 
 
1856		/*
1857		 * Find the deepest state from which the device can generate
1858		 * wake-up events, make it the target state and enable device
1859		 * to generate PME#.
1860		 */
1861		if (dev->pme_support) {
1862			while (target_state
1863			      && !(dev->pme_support & (1 << target_state)))
1864				target_state--;
1865		}
1866	}
1867
1868	return target_state;
1869}
1870
1871/**
1872 * pci_prepare_to_sleep - prepare PCI device for system-wide transition into a sleep state
 
1873 * @dev: Device to handle.
1874 *
1875 * Choose the power state appropriate for the device depending on whether
1876 * it can wake up the system and/or is power manageable by the platform
1877 * (PCI_D3hot is the default) and put the device into that state.
1878 */
1879int pci_prepare_to_sleep(struct pci_dev *dev)
1880{
1881	pci_power_t target_state = pci_target_state(dev);
 
1882	int error;
1883
1884	if (target_state == PCI_POWER_ERROR)
1885		return -EIO;
1886
1887	/* D3cold during system suspend/hibernate is not supported */
1888	if (target_state > PCI_D3hot)
1889		target_state = PCI_D3hot;
1890
1891	pci_enable_wake(dev, target_state, device_may_wakeup(&dev->dev));
1892
1893	error = pci_set_power_state(dev, target_state);
1894
1895	if (error)
1896		pci_enable_wake(dev, target_state, false);
1897
1898	return error;
1899}
 
1900
1901/**
1902 * pci_back_from_sleep - turn PCI device on during system-wide transition into working state
 
1903 * @dev: Device to handle.
1904 *
1905 * Disable device's system wake-up capability and put it into D0.
1906 */
1907int pci_back_from_sleep(struct pci_dev *dev)
1908{
1909	pci_enable_wake(dev, PCI_D0, false);
1910	return pci_set_power_state(dev, PCI_D0);
1911}
 
1912
1913/**
1914 * pci_finish_runtime_suspend - Carry out PCI-specific part of runtime suspend.
1915 * @dev: PCI device being suspended.
1916 *
1917 * Prepare @dev to generate wake-up events at run time and put it into a low
1918 * power state.
1919 */
1920int pci_finish_runtime_suspend(struct pci_dev *dev)
1921{
1922	pci_power_t target_state = pci_target_state(dev);
1923	int error;
1924
 
1925	if (target_state == PCI_POWER_ERROR)
1926		return -EIO;
1927
1928	dev->runtime_d3cold = target_state == PCI_D3cold;
1929
1930	__pci_enable_wake(dev, target_state, true, pci_dev_run_wake(dev));
1931
1932	error = pci_set_power_state(dev, target_state);
1933
1934	if (error) {
1935		__pci_enable_wake(dev, target_state, true, false);
1936		dev->runtime_d3cold = false;
1937	}
1938
1939	return error;
1940}
1941
1942/**
1943 * pci_dev_run_wake - Check if device can generate run-time wake-up events.
1944 * @dev: Device to check.
1945 *
1946 * Return true if the device itself is capable of generating wake-up events
1947 * (through the platform or using the native PCIe PME) or if the device supports
1948 * PME and one of its upstream bridges can generate wake-up events.
1949 */
1950bool pci_dev_run_wake(struct pci_dev *dev)
1951{
1952	struct pci_bus *bus = dev->bus;
1953
1954	if (device_run_wake(&dev->dev))
1955		return true;
1956
1957	if (!dev->pme_support)
 
1958		return false;
1959
 
 
 
1960	while (bus->parent) {
1961		struct pci_dev *bridge = bus->self;
1962
1963		if (device_run_wake(&bridge->dev))
1964			return true;
1965
1966		bus = bus->parent;
1967	}
1968
1969	/* We have reached the root bus. */
1970	if (bus->bridge)
1971		return device_run_wake(bus->bridge);
1972
1973	return false;
1974}
1975EXPORT_SYMBOL_GPL(pci_dev_run_wake);
1976
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1977void pci_config_pm_runtime_get(struct pci_dev *pdev)
1978{
1979	struct device *dev = &pdev->dev;
1980	struct device *parent = dev->parent;
1981
1982	if (parent)
1983		pm_runtime_get_sync(parent);
1984	pm_runtime_get_noresume(dev);
1985	/*
1986	 * pdev->current_state is set to PCI_D3cold during suspending,
1987	 * so wait until suspending completes
1988	 */
1989	pm_runtime_barrier(dev);
1990	/*
1991	 * Only need to resume devices in D3cold, because config
1992	 * registers are still accessible for devices suspended but
1993	 * not in D3cold.
1994	 */
1995	if (pdev->current_state == PCI_D3cold)
1996		pm_runtime_resume(dev);
1997}
1998
1999void pci_config_pm_runtime_put(struct pci_dev *pdev)
2000{
2001	struct device *dev = &pdev->dev;
2002	struct device *parent = dev->parent;
2003
2004	pm_runtime_put(dev);
2005	if (parent)
2006		pm_runtime_put_sync(parent);
2007}
2008
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2009/**
2010 * pci_pm_init - Initialize PM functions of given PCI device
2011 * @dev: PCI device to handle.
2012 */
2013void pci_pm_init(struct pci_dev *dev)
2014{
2015	int pm;
 
2016	u16 pmc;
2017
2018	pm_runtime_forbid(&dev->dev);
2019	pm_runtime_set_active(&dev->dev);
2020	pm_runtime_enable(&dev->dev);
2021	device_enable_async_suspend(&dev->dev);
2022	dev->wakeup_prepared = false;
2023
2024	dev->pm_cap = 0;
2025	dev->pme_support = 0;
2026
2027	/* find PCI PM capability in list */
2028	pm = pci_find_capability(dev, PCI_CAP_ID_PM);
2029	if (!pm)
2030		return;
2031	/* Check device's ability to generate PME# */
2032	pci_read_config_word(dev, pm + PCI_PM_PMC, &pmc);
2033
2034	if ((pmc & PCI_PM_CAP_VER_MASK) > 3) {
2035		dev_err(&dev->dev, "unsupported PM cap regs version (%u)\n",
2036			pmc & PCI_PM_CAP_VER_MASK);
2037		return;
2038	}
2039
2040	dev->pm_cap = pm;
2041	dev->d3_delay = PCI_PM_D3_WAIT;
2042	dev->d3cold_delay = PCI_PM_D3COLD_WAIT;
 
2043	dev->d3cold_allowed = true;
2044
2045	dev->d1_support = false;
2046	dev->d2_support = false;
2047	if (!pci_no_d1d2(dev)) {
2048		if (pmc & PCI_PM_CAP_D1)
2049			dev->d1_support = true;
2050		if (pmc & PCI_PM_CAP_D2)
2051			dev->d2_support = true;
2052
2053		if (dev->d1_support || dev->d2_support)
2054			dev_printk(KERN_DEBUG, &dev->dev, "supports%s%s\n",
2055				   dev->d1_support ? " D1" : "",
2056				   dev->d2_support ? " D2" : "");
2057	}
2058
2059	pmc &= PCI_PM_CAP_PME_MASK;
2060	if (pmc) {
2061		dev_printk(KERN_DEBUG, &dev->dev,
2062			 "PME# supported from%s%s%s%s%s\n",
2063			 (pmc & PCI_PM_CAP_PME_D0) ? " D0" : "",
2064			 (pmc & PCI_PM_CAP_PME_D1) ? " D1" : "",
2065			 (pmc & PCI_PM_CAP_PME_D2) ? " D2" : "",
2066			 (pmc & PCI_PM_CAP_PME_D3) ? " D3hot" : "",
2067			 (pmc & PCI_PM_CAP_PME_D3cold) ? " D3cold" : "");
2068		dev->pme_support = pmc >> PCI_PM_CAP_PME_SHIFT;
2069		dev->pme_poll = true;
2070		/*
2071		 * Make device's PM flags reflect the wake-up capability, but
2072		 * let the user space enable it to wake up the system as needed.
2073		 */
2074		device_set_wakeup_capable(&dev->dev, true);
2075		/* Disable the PME# generation functionality */
2076		pci_pme_active(dev, false);
2077	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2078}
2079
2080static void pci_add_saved_cap(struct pci_dev *pci_dev,
2081	struct pci_cap_saved_state *new_cap)
2082{
2083	hlist_add_head(&new_cap->next, &pci_dev->saved_cap_space);
2084}
2085
2086/**
2087 * _pci_add_cap_save_buffer - allocate buffer for saving given
2088 *                            capability registers
2089 * @dev: the PCI device
2090 * @cap: the capability to allocate the buffer for
2091 * @extended: Standard or Extended capability ID
2092 * @size: requested size of the buffer
2093 */
2094static int _pci_add_cap_save_buffer(struct pci_dev *dev, u16 cap,
2095				    bool extended, unsigned int size)
2096{
2097	int pos;
2098	struct pci_cap_saved_state *save_state;
2099
2100	if (extended)
2101		pos = pci_find_ext_capability(dev, cap);
2102	else
2103		pos = pci_find_capability(dev, cap);
2104
2105	if (pos <= 0)
2106		return 0;
2107
2108	save_state = kzalloc(sizeof(*save_state) + size, GFP_KERNEL);
2109	if (!save_state)
2110		return -ENOMEM;
2111
2112	save_state->cap.cap_nr = cap;
2113	save_state->cap.cap_extended = extended;
2114	save_state->cap.size = size;
2115	pci_add_saved_cap(dev, save_state);
2116
2117	return 0;
2118}
2119
2120int pci_add_cap_save_buffer(struct pci_dev *dev, char cap, unsigned int size)
2121{
2122	return _pci_add_cap_save_buffer(dev, cap, false, size);
2123}
2124
2125int pci_add_ext_cap_save_buffer(struct pci_dev *dev, u16 cap, unsigned int size)
2126{
2127	return _pci_add_cap_save_buffer(dev, cap, true, size);
2128}
2129
2130/**
2131 * pci_allocate_cap_save_buffers - allocate buffers for saving capabilities
2132 * @dev: the PCI device
2133 */
2134void pci_allocate_cap_save_buffers(struct pci_dev *dev)
2135{
2136	int error;
2137
2138	error = pci_add_cap_save_buffer(dev, PCI_CAP_ID_EXP,
2139					PCI_EXP_SAVE_REGS * sizeof(u16));
2140	if (error)
2141		dev_err(&dev->dev,
2142			"unable to preallocate PCI Express save buffer\n");
2143
2144	error = pci_add_cap_save_buffer(dev, PCI_CAP_ID_PCIX, sizeof(u16));
2145	if (error)
2146		dev_err(&dev->dev,
2147			"unable to preallocate PCI-X save buffer\n");
 
 
 
 
2148
2149	pci_allocate_vc_save_buffers(dev);
2150}
2151
2152void pci_free_cap_save_buffers(struct pci_dev *dev)
2153{
2154	struct pci_cap_saved_state *tmp;
2155	struct hlist_node *n;
2156
2157	hlist_for_each_entry_safe(tmp, n, &dev->saved_cap_space, next)
2158		kfree(tmp);
2159}
2160
2161/**
2162 * pci_configure_ari - enable or disable ARI forwarding
2163 * @dev: the PCI device
2164 *
2165 * If @dev and its upstream bridge both support ARI, enable ARI in the
2166 * bridge.  Otherwise, disable ARI in the bridge.
2167 */
2168void pci_configure_ari(struct pci_dev *dev)
2169{
2170	u32 cap;
2171	struct pci_dev *bridge;
2172
2173	if (pcie_ari_disabled || !pci_is_pcie(dev) || dev->devfn)
2174		return;
2175
2176	bridge = dev->bus->self;
2177	if (!bridge)
2178		return;
2179
2180	pcie_capability_read_dword(bridge, PCI_EXP_DEVCAP2, &cap);
2181	if (!(cap & PCI_EXP_DEVCAP2_ARI))
2182		return;
2183
2184	if (pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI)) {
2185		pcie_capability_set_word(bridge, PCI_EXP_DEVCTL2,
2186					 PCI_EXP_DEVCTL2_ARI);
2187		bridge->ari_enabled = 1;
2188	} else {
2189		pcie_capability_clear_word(bridge, PCI_EXP_DEVCTL2,
2190					   PCI_EXP_DEVCTL2_ARI);
2191		bridge->ari_enabled = 0;
2192	}
2193}
2194
2195static int pci_acs_enable;
2196
2197/**
2198 * pci_request_acs - ask for ACS to be enabled if supported
2199 */
2200void pci_request_acs(void)
2201{
2202	pci_acs_enable = 1;
2203}
2204
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2205/**
2206 * pci_std_enable_acs - enable ACS on devices using standard ACS capabilites
2207 * @dev: the PCI device
2208 */
2209static int pci_std_enable_acs(struct pci_dev *dev)
2210{
2211	int pos;
2212	u16 cap;
2213	u16 ctrl;
2214
2215	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ACS);
2216	if (!pos)
2217		return -ENODEV;
2218
2219	pci_read_config_word(dev, pos + PCI_ACS_CAP, &cap);
2220	pci_read_config_word(dev, pos + PCI_ACS_CTRL, &ctrl);
2221
2222	/* Source Validation */
2223	ctrl |= (cap & PCI_ACS_SV);
2224
2225	/* P2P Request Redirect */
2226	ctrl |= (cap & PCI_ACS_RR);
2227
2228	/* P2P Completion Redirect */
2229	ctrl |= (cap & PCI_ACS_CR);
2230
2231	/* Upstream Forwarding */
2232	ctrl |= (cap & PCI_ACS_UF);
2233
2234	pci_write_config_word(dev, pos + PCI_ACS_CTRL, ctrl);
2235
2236	return 0;
2237}
2238
2239/**
2240 * pci_enable_acs - enable ACS if hardware support it
2241 * @dev: the PCI device
2242 */
2243void pci_enable_acs(struct pci_dev *dev)
2244{
2245	if (!pci_acs_enable)
2246		return;
 
 
 
2247
2248	if (!pci_std_enable_acs(dev))
2249		return;
2250
2251	pci_dev_specific_enable_acs(dev);
 
 
 
 
 
 
 
 
2252}
2253
2254static bool pci_acs_flags_enabled(struct pci_dev *pdev, u16 acs_flags)
2255{
2256	int pos;
2257	u16 cap, ctrl;
2258
2259	pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_ACS);
2260	if (!pos)
2261		return false;
2262
2263	/*
2264	 * Except for egress control, capabilities are either required
2265	 * or only required if controllable.  Features missing from the
2266	 * capability field can therefore be assumed as hard-wired enabled.
2267	 */
2268	pci_read_config_word(pdev, pos + PCI_ACS_CAP, &cap);
2269	acs_flags &= (cap | PCI_ACS_EC);
2270
2271	pci_read_config_word(pdev, pos + PCI_ACS_CTRL, &ctrl);
2272	return (ctrl & acs_flags) == acs_flags;
2273}
2274
2275/**
2276 * pci_acs_enabled - test ACS against required flags for a given device
2277 * @pdev: device to test
2278 * @acs_flags: required PCI ACS flags
2279 *
2280 * Return true if the device supports the provided flags.  Automatically
2281 * filters out flags that are not implemented on multifunction devices.
2282 *
2283 * Note that this interface checks the effective ACS capabilities of the
2284 * device rather than the actual capabilities.  For instance, most single
2285 * function endpoints are not required to support ACS because they have no
2286 * opportunity for peer-to-peer access.  We therefore return 'true'
2287 * regardless of whether the device exposes an ACS capability.  This makes
2288 * it much easier for callers of this function to ignore the actual type
2289 * or topology of the device when testing ACS support.
2290 */
2291bool pci_acs_enabled(struct pci_dev *pdev, u16 acs_flags)
2292{
2293	int ret;
2294
2295	ret = pci_dev_specific_acs_enabled(pdev, acs_flags);
2296	if (ret >= 0)
2297		return ret > 0;
2298
2299	/*
2300	 * Conventional PCI and PCI-X devices never support ACS, either
2301	 * effectively or actually.  The shared bus topology implies that
2302	 * any device on the bus can receive or snoop DMA.
2303	 */
2304	if (!pci_is_pcie(pdev))
2305		return false;
2306
2307	switch (pci_pcie_type(pdev)) {
2308	/*
2309	 * PCI/X-to-PCIe bridges are not specifically mentioned by the spec,
2310	 * but since their primary interface is PCI/X, we conservatively
2311	 * handle them as we would a non-PCIe device.
2312	 */
2313	case PCI_EXP_TYPE_PCIE_BRIDGE:
2314	/*
2315	 * PCIe 3.0, 6.12.1 excludes ACS on these devices.  "ACS is never
2316	 * applicable... must never implement an ACS Extended Capability...".
2317	 * This seems arbitrary, but we take a conservative interpretation
2318	 * of this statement.
2319	 */
2320	case PCI_EXP_TYPE_PCI_BRIDGE:
2321	case PCI_EXP_TYPE_RC_EC:
2322		return false;
2323	/*
2324	 * PCIe 3.0, 6.12.1.1 specifies that downstream and root ports should
2325	 * implement ACS in order to indicate their peer-to-peer capabilities,
2326	 * regardless of whether they are single- or multi-function devices.
2327	 */
2328	case PCI_EXP_TYPE_DOWNSTREAM:
2329	case PCI_EXP_TYPE_ROOT_PORT:
2330		return pci_acs_flags_enabled(pdev, acs_flags);
2331	/*
2332	 * PCIe 3.0, 6.12.1.2 specifies ACS capabilities that should be
2333	 * implemented by the remaining PCIe types to indicate peer-to-peer
2334	 * capabilities, but only when they are part of a multifunction
2335	 * device.  The footnote for section 6.12 indicates the specific
2336	 * PCIe types included here.
2337	 */
2338	case PCI_EXP_TYPE_ENDPOINT:
2339	case PCI_EXP_TYPE_UPSTREAM:
2340	case PCI_EXP_TYPE_LEG_END:
2341	case PCI_EXP_TYPE_RC_END:
2342		if (!pdev->multifunction)
2343			break;
2344
2345		return pci_acs_flags_enabled(pdev, acs_flags);
2346	}
2347
2348	/*
2349	 * PCIe 3.0, 6.12.1.3 specifies no ACS capabilities are applicable
2350	 * to single function devices with the exception of downstream ports.
2351	 */
2352	return true;
2353}
2354
2355/**
2356 * pci_acs_path_enable - test ACS flags from start to end in a hierarchy
2357 * @start: starting downstream device
2358 * @end: ending upstream device or NULL to search to the root bus
2359 * @acs_flags: required flags
2360 *
2361 * Walk up a device tree from start to end testing PCI ACS support.  If
2362 * any step along the way does not support the required flags, return false.
2363 */
2364bool pci_acs_path_enabled(struct pci_dev *start,
2365			  struct pci_dev *end, u16 acs_flags)
2366{
2367	struct pci_dev *pdev, *parent = start;
2368
2369	do {
2370		pdev = parent;
2371
2372		if (!pci_acs_enabled(pdev, acs_flags))
2373			return false;
2374
2375		if (pci_is_root_bus(pdev->bus))
2376			return (end == NULL);
2377
2378		parent = pdev->bus->self;
2379	} while (pdev != end);
2380
2381	return true;
2382}
2383
2384/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2385 * pci_swizzle_interrupt_pin - swizzle INTx for device behind bridge
2386 * @dev: the PCI device
2387 * @pin: the INTx pin (1=INTA, 2=INTB, 3=INTC, 4=INTD)
2388 *
2389 * Perform INTx swizzling for a device behind one level of bridge.  This is
2390 * required by section 9.1 of the PCI-to-PCI bridge specification for devices
2391 * behind bridges on add-in cards.  For devices with ARI enabled, the slot
2392 * number is always 0 (see the Implementation Note in section 2.2.8.1 of
2393 * the PCI Express Base Specification, Revision 2.1)
2394 */
2395u8 pci_swizzle_interrupt_pin(const struct pci_dev *dev, u8 pin)
2396{
2397	int slot;
2398
2399	if (pci_ari_enabled(dev->bus))
2400		slot = 0;
2401	else
2402		slot = PCI_SLOT(dev->devfn);
2403
2404	return (((pin - 1) + slot) % 4) + 1;
2405}
2406
2407int
2408pci_get_interrupt_pin(struct pci_dev *dev, struct pci_dev **bridge)
2409{
2410	u8 pin;
2411
2412	pin = dev->pin;
2413	if (!pin)
2414		return -1;
2415
2416	while (!pci_is_root_bus(dev->bus)) {
2417		pin = pci_swizzle_interrupt_pin(dev, pin);
2418		dev = dev->bus->self;
2419	}
2420	*bridge = dev;
2421	return pin;
2422}
2423
2424/**
2425 * pci_common_swizzle - swizzle INTx all the way to root bridge
2426 * @dev: the PCI device
2427 * @pinp: pointer to the INTx pin value (1=INTA, 2=INTB, 3=INTD, 4=INTD)
2428 *
2429 * Perform INTx swizzling for a device.  This traverses through all PCI-to-PCI
2430 * bridges all the way up to a PCI root bus.
2431 */
2432u8 pci_common_swizzle(struct pci_dev *dev, u8 *pinp)
2433{
2434	u8 pin = *pinp;
2435
2436	while (!pci_is_root_bus(dev->bus)) {
2437		pin = pci_swizzle_interrupt_pin(dev, pin);
2438		dev = dev->bus->self;
2439	}
2440	*pinp = pin;
2441	return PCI_SLOT(dev->devfn);
2442}
 
2443
2444/**
2445 *	pci_release_region - Release a PCI bar
2446 *	@pdev: PCI device whose resources were previously reserved by pci_request_region
2447 *	@bar: BAR to release
2448 *
2449 *	Releases the PCI I/O and memory resources previously reserved by a
2450 *	successful call to pci_request_region.  Call this function only
2451 *	after all use of the PCI regions has ceased.
 
2452 */
2453void pci_release_region(struct pci_dev *pdev, int bar)
2454{
2455	struct pci_devres *dr;
2456
2457	if (pci_resource_len(pdev, bar) == 0)
2458		return;
2459	if (pci_resource_flags(pdev, bar) & IORESOURCE_IO)
2460		release_region(pci_resource_start(pdev, bar),
2461				pci_resource_len(pdev, bar));
2462	else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM)
2463		release_mem_region(pci_resource_start(pdev, bar),
2464				pci_resource_len(pdev, bar));
2465
2466	dr = find_pci_dr(pdev);
2467	if (dr)
2468		dr->region_mask &= ~(1 << bar);
2469}
 
2470
2471/**
2472 *	__pci_request_region - Reserved PCI I/O and memory resource
2473 *	@pdev: PCI device whose resources are to be reserved
2474 *	@bar: BAR to be reserved
2475 *	@res_name: Name to be associated with resource.
2476 *	@exclusive: whether the region access is exclusive or not
2477 *
2478 *	Mark the PCI region associated with PCI device @pdev BR @bar as
2479 *	being reserved by owner @res_name.  Do not access any
2480 *	address inside the PCI regions unless this call returns
2481 *	successfully.
2482 *
2483 *	If @exclusive is set, then the region is marked so that userspace
2484 *	is explicitly not allowed to map the resource via /dev/mem or
2485 *	sysfs MMIO access.
2486 *
2487 *	Returns 0 on success, or %EBUSY on error.  A warning
2488 *	message is also printed on failure.
2489 */
2490static int __pci_request_region(struct pci_dev *pdev, int bar, const char *res_name,
2491									int exclusive)
2492{
2493	struct pci_devres *dr;
2494
2495	if (pci_resource_len(pdev, bar) == 0)
2496		return 0;
2497
2498	if (pci_resource_flags(pdev, bar) & IORESOURCE_IO) {
2499		if (!request_region(pci_resource_start(pdev, bar),
2500			    pci_resource_len(pdev, bar), res_name))
2501			goto err_out;
2502	}
2503	else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM) {
2504		if (!__request_mem_region(pci_resource_start(pdev, bar),
2505					pci_resource_len(pdev, bar), res_name,
2506					exclusive))
2507			goto err_out;
2508	}
2509
2510	dr = find_pci_dr(pdev);
2511	if (dr)
2512		dr->region_mask |= 1 << bar;
2513
2514	return 0;
2515
2516err_out:
2517	dev_warn(&pdev->dev, "BAR %d: can't reserve %pR\n", bar,
2518		 &pdev->resource[bar]);
2519	return -EBUSY;
2520}
2521
2522/**
2523 *	pci_request_region - Reserve PCI I/O and memory resource
2524 *	@pdev: PCI device whose resources are to be reserved
2525 *	@bar: BAR to be reserved
2526 *	@res_name: Name to be associated with resource
2527 *
2528 *	Mark the PCI region associated with PCI device @pdev BAR @bar as
2529 *	being reserved by owner @res_name.  Do not access any
2530 *	address inside the PCI regions unless this call returns
2531 *	successfully.
2532 *
2533 *	Returns 0 on success, or %EBUSY on error.  A warning
2534 *	message is also printed on failure.
2535 */
2536int pci_request_region(struct pci_dev *pdev, int bar, const char *res_name)
2537{
2538	return __pci_request_region(pdev, bar, res_name, 0);
2539}
 
2540
2541/**
2542 *	pci_request_region_exclusive - Reserved PCI I/O and memory resource
2543 *	@pdev: PCI device whose resources are to be reserved
2544 *	@bar: BAR to be reserved
2545 *	@res_name: Name to be associated with resource.
2546 *
2547 *	Mark the PCI region associated with PCI device @pdev BR @bar as
2548 *	being reserved by owner @res_name.  Do not access any
2549 *	address inside the PCI regions unless this call returns
2550 *	successfully.
2551 *
2552 *	Returns 0 on success, or %EBUSY on error.  A warning
2553 *	message is also printed on failure.
2554 *
2555 *	The key difference that _exclusive makes it that userspace is
2556 *	explicitly not allowed to map the resource via /dev/mem or
2557 *	sysfs.
2558 */
2559int pci_request_region_exclusive(struct pci_dev *pdev, int bar, const char *res_name)
2560{
2561	return __pci_request_region(pdev, bar, res_name, IORESOURCE_EXCLUSIVE);
2562}
2563/**
2564 * pci_release_selected_regions - Release selected PCI I/O and memory resources
2565 * @pdev: PCI device whose resources were previously reserved
2566 * @bars: Bitmask of BARs to be released
2567 *
2568 * Release selected PCI I/O and memory resources previously reserved.
2569 * Call this function only after all use of the PCI regions has ceased.
2570 */
2571void pci_release_selected_regions(struct pci_dev *pdev, int bars)
2572{
2573	int i;
2574
2575	for (i = 0; i < 6; i++)
2576		if (bars & (1 << i))
2577			pci_release_region(pdev, i);
2578}
 
2579
2580static int __pci_request_selected_regions(struct pci_dev *pdev, int bars,
2581				 const char *res_name, int excl)
2582{
2583	int i;
2584
2585	for (i = 0; i < 6; i++)
2586		if (bars & (1 << i))
2587			if (__pci_request_region(pdev, i, res_name, excl))
2588				goto err_out;
2589	return 0;
2590
2591err_out:
2592	while(--i >= 0)
2593		if (bars & (1 << i))
2594			pci_release_region(pdev, i);
2595
2596	return -EBUSY;
2597}
2598
2599
2600/**
2601 * pci_request_selected_regions - Reserve selected PCI I/O and memory resources
2602 * @pdev: PCI device whose resources are to be reserved
2603 * @bars: Bitmask of BARs to be requested
2604 * @res_name: Name to be associated with resource
2605 */
2606int pci_request_selected_regions(struct pci_dev *pdev, int bars,
2607				 const char *res_name)
2608{
2609	return __pci_request_selected_regions(pdev, bars, res_name, 0);
2610}
 
2611
2612int pci_request_selected_regions_exclusive(struct pci_dev *pdev,
2613				 int bars, const char *res_name)
2614{
2615	return __pci_request_selected_regions(pdev, bars, res_name,
2616			IORESOURCE_EXCLUSIVE);
2617}
 
2618
2619/**
2620 *	pci_release_regions - Release reserved PCI I/O and memory resources
2621 *	@pdev: PCI device whose resources were previously reserved by pci_request_regions
2622 *
2623 *	Releases all PCI I/O and memory resources previously reserved by a
2624 *	successful call to pci_request_regions.  Call this function only
2625 *	after all use of the PCI regions has ceased.
 
2626 */
2627
2628void pci_release_regions(struct pci_dev *pdev)
2629{
2630	pci_release_selected_regions(pdev, (1 << 6) - 1);
2631}
 
2632
2633/**
2634 *	pci_request_regions - Reserved PCI I/O and memory resources
2635 *	@pdev: PCI device whose resources are to be reserved
2636 *	@res_name: Name to be associated with resource.
2637 *
2638 *	Mark all PCI regions associated with PCI device @pdev as
2639 *	being reserved by owner @res_name.  Do not access any
2640 *	address inside the PCI regions unless this call returns
2641 *	successfully.
2642 *
2643 *	Returns 0 on success, or %EBUSY on error.  A warning
2644 *	message is also printed on failure.
 
 
 
 
 
2645 */
2646int pci_request_regions(struct pci_dev *pdev, const char *res_name)
2647{
2648	return pci_request_selected_regions(pdev, ((1 << 6) - 1), res_name);
2649}
 
2650
2651/**
2652 *	pci_request_regions_exclusive - Reserved PCI I/O and memory resources
2653 *	@pdev: PCI device whose resources are to be reserved
2654 *	@res_name: Name to be associated with resource.
2655 *
2656 *	Mark all PCI regions associated with PCI device @pdev as
2657 *	being reserved by owner @res_name.  Do not access any
2658 *	address inside the PCI regions unless this call returns
2659 *	successfully.
2660 *
2661 *	pci_request_regions_exclusive() will mark the region so that
2662 *	/dev/mem and the sysfs MMIO access will not be allowed.
 
2663 *
2664 *	Returns 0 on success, or %EBUSY on error.  A warning
2665 *	message is also printed on failure.
 
 
 
2666 */
2667int pci_request_regions_exclusive(struct pci_dev *pdev, const char *res_name)
2668{
2669	return pci_request_selected_regions_exclusive(pdev,
2670					((1 << 6) - 1), res_name);
2671}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2672
2673static void __pci_set_master(struct pci_dev *dev, bool enable)
2674{
2675	u16 old_cmd, cmd;
2676
2677	pci_read_config_word(dev, PCI_COMMAND, &old_cmd);
2678	if (enable)
2679		cmd = old_cmd | PCI_COMMAND_MASTER;
2680	else
2681		cmd = old_cmd & ~PCI_COMMAND_MASTER;
2682	if (cmd != old_cmd) {
2683		dev_dbg(&dev->dev, "%s bus mastering\n",
2684			enable ? "enabling" : "disabling");
2685		pci_write_config_word(dev, PCI_COMMAND, cmd);
2686	}
2687	dev->is_busmaster = enable;
2688}
2689
2690/**
2691 * pcibios_setup - process "pci=" kernel boot arguments
2692 * @str: string used to pass in "pci=" kernel boot arguments
2693 *
2694 * Process kernel boot arguments.  This is the default implementation.
2695 * Architecture specific implementations can override this as necessary.
2696 */
2697char * __weak __init pcibios_setup(char *str)
2698{
2699	return str;
2700}
2701
2702/**
2703 * pcibios_set_master - enable PCI bus-mastering for device dev
2704 * @dev: the PCI device to enable
2705 *
2706 * Enables PCI bus-mastering for the device.  This is the default
2707 * implementation.  Architecture specific implementations can override
2708 * this if necessary.
2709 */
2710void __weak pcibios_set_master(struct pci_dev *dev)
2711{
2712	u8 lat;
2713
2714	/* The latency timer doesn't apply to PCIe (either Type 0 or Type 1) */
2715	if (pci_is_pcie(dev))
2716		return;
2717
2718	pci_read_config_byte(dev, PCI_LATENCY_TIMER, &lat);
2719	if (lat < 16)
2720		lat = (64 <= pcibios_max_latency) ? 64 : pcibios_max_latency;
2721	else if (lat > pcibios_max_latency)
2722		lat = pcibios_max_latency;
2723	else
2724		return;
2725
2726	pci_write_config_byte(dev, PCI_LATENCY_TIMER, lat);
2727}
2728
2729/**
2730 * pci_set_master - enables bus-mastering for device dev
2731 * @dev: the PCI device to enable
2732 *
2733 * Enables bus-mastering on the device and calls pcibios_set_master()
2734 * to do the needed arch specific settings.
2735 */
2736void pci_set_master(struct pci_dev *dev)
2737{
2738	__pci_set_master(dev, true);
2739	pcibios_set_master(dev);
2740}
 
2741
2742/**
2743 * pci_clear_master - disables bus-mastering for device dev
2744 * @dev: the PCI device to disable
2745 */
2746void pci_clear_master(struct pci_dev *dev)
2747{
2748	__pci_set_master(dev, false);
2749}
 
2750
2751/**
2752 * pci_set_cacheline_size - ensure the CACHE_LINE_SIZE register is programmed
2753 * @dev: the PCI device for which MWI is to be enabled
2754 *
2755 * Helper function for pci_set_mwi.
2756 * Originally copied from drivers/net/acenic.c.
2757 * Copyright 1998-2001 by Jes Sorensen, <jes@trained-monkey.org>.
2758 *
2759 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
2760 */
2761int pci_set_cacheline_size(struct pci_dev *dev)
2762{
2763	u8 cacheline_size;
2764
2765	if (!pci_cache_line_size)
2766		return -EINVAL;
2767
2768	/* Validate current setting: the PCI_CACHE_LINE_SIZE must be
2769	   equal to or multiple of the right value. */
2770	pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
2771	if (cacheline_size >= pci_cache_line_size &&
2772	    (cacheline_size % pci_cache_line_size) == 0)
2773		return 0;
2774
2775	/* Write the correct value. */
2776	pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, pci_cache_line_size);
2777	/* Read it back. */
2778	pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
2779	if (cacheline_size == pci_cache_line_size)
2780		return 0;
2781
2782	dev_printk(KERN_DEBUG, &dev->dev, "cache line size of %d is not "
2783		   "supported\n", pci_cache_line_size << 2);
2784
2785	return -EINVAL;
2786}
2787EXPORT_SYMBOL_GPL(pci_set_cacheline_size);
2788
2789#ifdef PCI_DISABLE_MWI
2790int pci_set_mwi(struct pci_dev *dev)
2791{
2792	return 0;
2793}
2794
2795int pci_try_set_mwi(struct pci_dev *dev)
2796{
2797	return 0;
2798}
2799
2800void pci_clear_mwi(struct pci_dev *dev)
2801{
2802}
2803
2804#else
2805
2806/**
2807 * pci_set_mwi - enables memory-write-invalidate PCI transaction
2808 * @dev: the PCI device for which MWI is enabled
2809 *
2810 * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND.
2811 *
2812 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
2813 */
2814int
2815pci_set_mwi(struct pci_dev *dev)
2816{
 
 
 
2817	int rc;
2818	u16 cmd;
2819
2820	rc = pci_set_cacheline_size(dev);
2821	if (rc)
2822		return rc;
2823
2824	pci_read_config_word(dev, PCI_COMMAND, &cmd);
2825	if (! (cmd & PCI_COMMAND_INVALIDATE)) {
2826		dev_dbg(&dev->dev, "enabling Mem-Wr-Inval\n");
2827		cmd |= PCI_COMMAND_INVALIDATE;
2828		pci_write_config_word(dev, PCI_COMMAND, cmd);
2829	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2830
2831	return 0;
 
2832}
 
2833
2834/**
2835 * pci_try_set_mwi - enables memory-write-invalidate PCI transaction
2836 * @dev: the PCI device for which MWI is enabled
2837 *
2838 * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND.
2839 * Callers are not required to check the return value.
2840 *
2841 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
2842 */
2843int pci_try_set_mwi(struct pci_dev *dev)
2844{
2845	int rc = pci_set_mwi(dev);
2846	return rc;
 
 
 
2847}
 
2848
2849/**
2850 * pci_clear_mwi - disables Memory-Write-Invalidate for device dev
2851 * @dev: the PCI device to disable
2852 *
2853 * Disables PCI Memory-Write-Invalidate transaction on the device
2854 */
2855void
2856pci_clear_mwi(struct pci_dev *dev)
2857{
 
2858	u16 cmd;
2859
2860	pci_read_config_word(dev, PCI_COMMAND, &cmd);
2861	if (cmd & PCI_COMMAND_INVALIDATE) {
2862		cmd &= ~PCI_COMMAND_INVALIDATE;
2863		pci_write_config_word(dev, PCI_COMMAND, cmd);
2864	}
 
2865}
2866#endif /* ! PCI_DISABLE_MWI */
2867
2868/**
2869 * pci_intx - enables/disables PCI INTx for device dev
2870 * @pdev: the PCI device to operate on
2871 * @enable: boolean: whether to enable or disable PCI INTx
2872 *
2873 * Enables/disables PCI INTx for device dev
2874 */
2875void
2876pci_intx(struct pci_dev *pdev, int enable)
2877{
2878	u16 pci_command, new;
2879
2880	pci_read_config_word(pdev, PCI_COMMAND, &pci_command);
2881
2882	if (enable) {
2883		new = pci_command & ~PCI_COMMAND_INTX_DISABLE;
2884	} else {
2885		new = pci_command | PCI_COMMAND_INTX_DISABLE;
2886	}
2887
2888	if (new != pci_command) {
2889		struct pci_devres *dr;
2890
2891		pci_write_config_word(pdev, PCI_COMMAND, new);
2892
2893		dr = find_pci_dr(pdev);
2894		if (dr && !dr->restore_intx) {
2895			dr->restore_intx = 1;
2896			dr->orig_intx = !enable;
2897		}
2898	}
2899}
2900
2901/**
2902 * pci_intx_mask_supported - probe for INTx masking support
2903 * @dev: the PCI device to operate on
2904 *
2905 * Check if the device dev support INTx masking via the config space
2906 * command word.
2907 */
2908bool pci_intx_mask_supported(struct pci_dev *dev)
2909{
2910	bool mask_supported = false;
2911	u16 orig, new;
2912
2913	if (dev->broken_intx_masking)
2914		return false;
2915
2916	pci_cfg_access_lock(dev);
2917
2918	pci_read_config_word(dev, PCI_COMMAND, &orig);
2919	pci_write_config_word(dev, PCI_COMMAND,
2920			      orig ^ PCI_COMMAND_INTX_DISABLE);
2921	pci_read_config_word(dev, PCI_COMMAND, &new);
2922
2923	/*
2924	 * There's no way to protect against hardware bugs or detect them
2925	 * reliably, but as long as we know what the value should be, let's
2926	 * go ahead and check it.
2927	 */
2928	if ((new ^ orig) & ~PCI_COMMAND_INTX_DISABLE) {
2929		dev_err(&dev->dev, "Command register changed from "
2930			"0x%x to 0x%x: driver or hardware bug?\n", orig, new);
2931	} else if ((new ^ orig) & PCI_COMMAND_INTX_DISABLE) {
2932		mask_supported = true;
2933		pci_write_config_word(dev, PCI_COMMAND, orig);
2934	}
2935
2936	pci_cfg_access_unlock(dev);
2937	return mask_supported;
2938}
2939EXPORT_SYMBOL_GPL(pci_intx_mask_supported);
2940
2941static bool pci_check_and_set_intx_mask(struct pci_dev *dev, bool mask)
2942{
2943	struct pci_bus *bus = dev->bus;
2944	bool mask_updated = true;
2945	u32 cmd_status_dword;
2946	u16 origcmd, newcmd;
2947	unsigned long flags;
2948	bool irq_pending;
2949
2950	/*
2951	 * We do a single dword read to retrieve both command and status.
2952	 * Document assumptions that make this possible.
2953	 */
2954	BUILD_BUG_ON(PCI_COMMAND % 4);
2955	BUILD_BUG_ON(PCI_COMMAND + 2 != PCI_STATUS);
2956
2957	raw_spin_lock_irqsave(&pci_lock, flags);
2958
2959	bus->ops->read(bus, dev->devfn, PCI_COMMAND, 4, &cmd_status_dword);
2960
2961	irq_pending = (cmd_status_dword >> 16) & PCI_STATUS_INTERRUPT;
2962
2963	/*
2964	 * Check interrupt status register to see whether our device
2965	 * triggered the interrupt (when masking) or the next IRQ is
2966	 * already pending (when unmasking).
2967	 */
2968	if (mask != irq_pending) {
2969		mask_updated = false;
2970		goto done;
2971	}
2972
2973	origcmd = cmd_status_dword;
2974	newcmd = origcmd & ~PCI_COMMAND_INTX_DISABLE;
2975	if (mask)
2976		newcmd |= PCI_COMMAND_INTX_DISABLE;
2977	if (newcmd != origcmd)
2978		bus->ops->write(bus, dev->devfn, PCI_COMMAND, 2, newcmd);
2979
2980done:
2981	raw_spin_unlock_irqrestore(&pci_lock, flags);
2982
2983	return mask_updated;
2984}
2985
2986/**
2987 * pci_check_and_mask_intx - mask INTx on pending interrupt
2988 * @dev: the PCI device to operate on
2989 *
2990 * Check if the device dev has its INTx line asserted, mask it and
2991 * return true in that case. False is returned if not interrupt was
2992 * pending.
2993 */
2994bool pci_check_and_mask_intx(struct pci_dev *dev)
2995{
2996	return pci_check_and_set_intx_mask(dev, true);
2997}
2998EXPORT_SYMBOL_GPL(pci_check_and_mask_intx);
2999
3000/**
3001 * pci_check_and_unmask_intx - unmask INTx if no interrupt is pending
3002 * @dev: the PCI device to operate on
3003 *
3004 * Check if the device dev has its INTx line asserted, unmask it if not
3005 * and return true. False is returned and the mask remains active if
3006 * there was still an interrupt pending.
3007 */
3008bool pci_check_and_unmask_intx(struct pci_dev *dev)
3009{
3010	return pci_check_and_set_intx_mask(dev, false);
3011}
3012EXPORT_SYMBOL_GPL(pci_check_and_unmask_intx);
3013
3014/**
3015 * pci_msi_off - disables any MSI or MSI-X capabilities
3016 * @dev: the PCI device to operate on
3017 *
3018 * If you want to use MSI, see pci_enable_msi() and friends.
3019 * This is a lower-level primitive that allows us to disable
3020 * MSI operation at the device level.
3021 */
3022void pci_msi_off(struct pci_dev *dev)
 
 
 
 
 
 
 
 
 
 
3023{
3024	int pos;
3025	u16 control;
3026
3027	/*
3028	 * This looks like it could go in msi.c, but we need it even when
3029	 * CONFIG_PCI_MSI=n.  For the same reason, we can't use
3030	 * dev->msi_cap or dev->msix_cap here.
 
 
 
 
 
 
 
3031	 */
3032	pos = pci_find_capability(dev, PCI_CAP_ID_MSI);
3033	if (pos) {
3034		pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &control);
3035		control &= ~PCI_MSI_FLAGS_ENABLE;
3036		pci_write_config_word(dev, pos + PCI_MSI_FLAGS, control);
3037	}
3038	pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);
3039	if (pos) {
3040		pci_read_config_word(dev, pos + PCI_MSIX_FLAGS, &control);
3041		control &= ~PCI_MSIX_FLAGS_ENABLE;
3042		pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control);
 
 
 
 
3043	}
3044}
3045EXPORT_SYMBOL_GPL(pci_msi_off);
3046
3047int pci_set_dma_max_seg_size(struct pci_dev *dev, unsigned int size)
3048{
3049	return dma_set_max_seg_size(&dev->dev, size);
3050}
3051EXPORT_SYMBOL(pci_set_dma_max_seg_size);
3052
3053int pci_set_dma_seg_boundary(struct pci_dev *dev, unsigned long mask)
3054{
3055	return dma_set_seg_boundary(&dev->dev, mask);
3056}
3057EXPORT_SYMBOL(pci_set_dma_seg_boundary);
3058
3059/**
3060 * pci_wait_for_pending_transaction - waits for pending transaction
3061 * @dev: the PCI device to operate on
3062 *
3063 * Return 0 if transaction is pending 1 otherwise.
 
3064 */
3065int pci_wait_for_pending_transaction(struct pci_dev *dev)
3066{
3067	if (!pci_is_pcie(dev))
3068		return 1;
 
 
3069
3070	return pci_wait_for_pending(dev, pci_pcie_cap(dev) + PCI_EXP_DEVSTA,
3071				    PCI_EXP_DEVSTA_TRPND);
3072}
3073EXPORT_SYMBOL(pci_wait_for_pending_transaction);
3074
3075static int pcie_flr(struct pci_dev *dev, int probe)
 
 
 
 
 
 
 
 
3076{
3077	u32 cap;
 
3078
3079	pcie_capability_read_dword(dev, PCI_EXP_DEVCAP, &cap);
3080	if (!(cap & PCI_EXP_DEVCAP_FLR))
3081		return -ENOTTY;
3082
3083	if (probe)
3084		return 0;
3085
3086	if (!pci_wait_for_pending_transaction(dev))
3087		dev_err(&dev->dev, "transaction is not cleared; proceeding with reset anyway\n");
3088
3089	pcie_capability_set_word(dev, PCI_EXP_DEVCTL, PCI_EXP_DEVCTL_BCR_FLR);
3090
3091	msleep(100);
3092
3093	return 0;
3094}
 
3095
3096static int pci_af_flr(struct pci_dev *dev, int probe)
3097{
3098	int pos;
3099	u8 cap;
3100
3101	pos = pci_find_capability(dev, PCI_CAP_ID_AF);
3102	if (!pos)
3103		return -ENOTTY;
3104
 
 
 
3105	pci_read_config_byte(dev, pos + PCI_AF_CAP, &cap);
3106	if (!(cap & PCI_AF_CAP_TP) || !(cap & PCI_AF_CAP_FLR))
3107		return -ENOTTY;
3108
3109	if (probe)
3110		return 0;
3111
3112	/* Wait for Transaction Pending bit clean */
3113	if (pci_wait_for_pending(dev, pos + PCI_AF_STATUS, PCI_AF_STATUS_TP))
3114		goto clear;
 
 
 
 
 
 
 
3115
3116	dev_err(&dev->dev, "transaction is not cleared; "
3117			"proceeding with reset anyway\n");
3118
3119clear:
3120	pci_write_config_byte(dev, pos + PCI_AF_CTRL, PCI_AF_CTRL_FLR);
 
 
 
 
3121	msleep(100);
3122
3123	return 0;
3124}
3125
3126/**
3127 * pci_pm_reset - Put device into PCI_D3 and back into PCI_D0.
3128 * @dev: Device to reset.
3129 * @probe: If set, only check if the device can be reset this way.
3130 *
3131 * If @dev supports native PCI PM and its PCI_PM_CTRL_NO_SOFT_RESET flag is
3132 * unset, it will be reinitialized internally when going from PCI_D3hot to
3133 * PCI_D0.  If that's the case and the device is not in a low-power state
3134 * already, force it into PCI_D3hot and back to PCI_D0, causing it to be reset.
3135 *
3136 * NOTE: This causes the caller to sleep for twice the device power transition
3137 * cooldown period, which for the D0->D3hot and D3hot->D0 transitions is 10 ms
3138 * by default (i.e. unless the @dev's d3_delay field has a different value).
3139 * Moreover, only devices in D0 can be reset by this function.
3140 */
3141static int pci_pm_reset(struct pci_dev *dev, int probe)
3142{
3143	u16 csr;
3144
3145	if (!dev->pm_cap)
3146		return -ENOTTY;
3147
3148	pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &csr);
3149	if (csr & PCI_PM_CTRL_NO_SOFT_RESET)
3150		return -ENOTTY;
3151
3152	if (probe)
3153		return 0;
3154
3155	if (dev->current_state != PCI_D0)
3156		return -EINVAL;
3157
3158	csr &= ~PCI_PM_CTRL_STATE_MASK;
3159	csr |= PCI_D3hot;
3160	pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, csr);
3161	pci_dev_d3_sleep(dev);
3162
3163	csr &= ~PCI_PM_CTRL_STATE_MASK;
3164	csr |= PCI_D0;
3165	pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, csr);
3166	pci_dev_d3_sleep(dev);
3167
3168	return 0;
3169}
3170
3171/**
3172 * pci_reset_bridge_secondary_bus - Reset the secondary bus on a PCI bridge.
3173 * @dev: Bridge device
 
3174 *
3175 * Use the bridge control register to assert reset on the secondary bus.
3176 * Devices on the secondary bus are left in power-on state.
3177 */
3178void pci_reset_bridge_secondary_bus(struct pci_dev *dev)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3179{
3180	u16 ctrl;
3181
3182	pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &ctrl);
3183	ctrl |= PCI_BRIDGE_CTL_BUS_RESET;
3184	pci_write_config_word(dev, PCI_BRIDGE_CONTROL, ctrl);
 
3185	/*
3186	 * PCI spec v3.0 7.6.4.2 requires minimum Trst of 1ms.  Double
3187	 * this to 2ms to ensure that we meet the minimum requirement.
3188	 */
3189	msleep(2);
3190
3191	ctrl &= ~PCI_BRIDGE_CTL_BUS_RESET;
3192	pci_write_config_word(dev, PCI_BRIDGE_CONTROL, ctrl);
3193
3194	/*
3195	 * Trhfa for conventional PCI is 2^25 clock cycles.
3196	 * Assuming a minimum 33MHz clock this results in a 1s
3197	 * delay before we can consider subordinate devices to
3198	 * be re-initialized.  PCIe has some ways to shorten this,
3199	 * but we don't make use of them yet.
3200	 */
3201	ssleep(1);
3202}
3203EXPORT_SYMBOL_GPL(pci_reset_bridge_secondary_bus);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3204
3205static int pci_parent_bus_reset(struct pci_dev *dev, int probe)
3206{
3207	struct pci_dev *pdev;
3208
3209	if (pci_is_root_bus(dev->bus) || dev->subordinate || !dev->bus->self)
 
3210		return -ENOTTY;
3211
3212	list_for_each_entry(pdev, &dev->bus->devices, bus_list)
3213		if (pdev != dev)
3214			return -ENOTTY;
3215
3216	if (probe)
3217		return 0;
3218
3219	pci_reset_bridge_secondary_bus(dev->bus->self);
3220
3221	return 0;
3222}
3223
3224static int pci_reset_hotplug_slot(struct hotplug_slot *hotplug, int probe)
3225{
3226	int rc = -ENOTTY;
3227
3228	if (!hotplug || !try_module_get(hotplug->ops->owner))
3229		return rc;
3230
3231	if (hotplug->ops->reset_slot)
3232		rc = hotplug->ops->reset_slot(hotplug, probe);
3233
3234	module_put(hotplug->ops->owner);
3235
3236	return rc;
3237}
3238
3239static int pci_dev_reset_slot_function(struct pci_dev *dev, int probe)
3240{
3241	struct pci_dev *pdev;
3242
3243	if (dev->subordinate || !dev->slot)
 
3244		return -ENOTTY;
3245
3246	list_for_each_entry(pdev, &dev->bus->devices, bus_list)
3247		if (pdev != dev && pdev->slot == dev->slot)
3248			return -ENOTTY;
3249
3250	return pci_reset_hotplug_slot(dev->slot->hotplug, probe);
3251}
3252
3253static int __pci_dev_reset(struct pci_dev *dev, int probe)
3254{
3255	int rc;
3256
3257	might_sleep();
3258
3259	rc = pci_dev_specific_reset(dev, probe);
3260	if (rc != -ENOTTY)
3261		goto done;
3262
3263	rc = pcie_flr(dev, probe);
3264	if (rc != -ENOTTY)
3265		goto done;
3266
3267	rc = pci_af_flr(dev, probe);
3268	if (rc != -ENOTTY)
3269		goto done;
3270
3271	rc = pci_pm_reset(dev, probe);
3272	if (rc != -ENOTTY)
3273		goto done;
3274
3275	rc = pci_dev_reset_slot_function(dev, probe);
3276	if (rc != -ENOTTY)
3277		goto done;
3278
3279	rc = pci_parent_bus_reset(dev, probe);
3280done:
3281	return rc;
3282}
3283
3284static void pci_dev_lock(struct pci_dev *dev)
3285{
3286	pci_cfg_access_lock(dev);
3287	/* block PM suspend, driver probe, etc. */
3288	device_lock(&dev->dev);
3289}
3290
3291/* Return 1 on successful lock, 0 on contention */
3292static int pci_dev_trylock(struct pci_dev *dev)
3293{
3294	if (pci_cfg_access_trylock(dev)) {
3295		if (device_trylock(&dev->dev))
3296			return 1;
3297		pci_cfg_access_unlock(dev);
3298	}
3299
3300	return 0;
3301}
3302
3303static void pci_dev_unlock(struct pci_dev *dev)
3304{
3305	device_unlock(&dev->dev);
3306	pci_cfg_access_unlock(dev);
3307}
3308
3309static void pci_dev_save_and_disable(struct pci_dev *dev)
3310{
 
 
 
 
 
 
 
 
 
 
 
3311	/*
3312	 * Wake-up device prior to save.  PM registers default to D0 after
3313	 * reset and a simple register restore doesn't reliably return
3314	 * to a non-D0 state anyway.
3315	 */
3316	pci_set_power_state(dev, PCI_D0);
3317
3318	pci_save_state(dev);
3319	/*
3320	 * Disable the device by clearing the Command register, except for
3321	 * INTx-disable which is set.  This not only disables MMIO and I/O port
3322	 * BARs, but also prevents the device from being Bus Master, preventing
3323	 * DMA from the device including MSI/MSI-X interrupts.  For PCI 2.3
3324	 * compliant devices, INTx-disable prevents legacy interrupts.
3325	 */
3326	pci_write_config_word(dev, PCI_COMMAND, PCI_COMMAND_INTX_DISABLE);
3327}
3328
3329static void pci_dev_restore(struct pci_dev *dev)
3330{
 
 
 
3331	pci_restore_state(dev);
3332}
3333
3334static int pci_dev_reset(struct pci_dev *dev, int probe)
3335{
3336	int rc;
3337
3338	if (!probe)
3339		pci_dev_lock(dev);
3340
3341	rc = __pci_dev_reset(dev, probe);
3342
3343	if (!probe)
3344		pci_dev_unlock(dev);
3345
3346	return rc;
3347}
3348/**
3349 * __pci_reset_function - reset a PCI device function
3350 * @dev: PCI device to reset
3351 *
3352 * Some devices allow an individual function to be reset without affecting
3353 * other functions in the same device.  The PCI device must be responsive
3354 * to PCI config space in order to use this function.
3355 *
3356 * The device function is presumed to be unused when this function is called.
3357 * Resetting the device will make the contents of PCI configuration space
3358 * random, so any caller of this must be prepared to reinitialise the
3359 * device including MSI, bus mastering, BARs, decoding IO and memory spaces,
3360 * etc.
3361 *
3362 * Returns 0 if the device function was successfully reset or negative if the
3363 * device doesn't support resetting a single function.
3364 */
3365int __pci_reset_function(struct pci_dev *dev)
3366{
3367	return pci_dev_reset(dev, 0);
3368}
3369EXPORT_SYMBOL_GPL(__pci_reset_function);
3370
3371/**
3372 * __pci_reset_function_locked - reset a PCI device function while holding
3373 * the @dev mutex lock.
3374 * @dev: PCI device to reset
3375 *
3376 * Some devices allow an individual function to be reset without affecting
3377 * other functions in the same device.  The PCI device must be responsive
3378 * to PCI config space in order to use this function.
3379 *
3380 * The device function is presumed to be unused and the caller is holding
3381 * the device mutex lock when this function is called.
 
3382 * Resetting the device will make the contents of PCI configuration space
3383 * random, so any caller of this must be prepared to reinitialise the
3384 * device including MSI, bus mastering, BARs, decoding IO and memory spaces,
3385 * etc.
3386 *
3387 * Returns 0 if the device function was successfully reset or negative if the
3388 * device doesn't support resetting a single function.
3389 */
3390int __pci_reset_function_locked(struct pci_dev *dev)
3391{
3392	return __pci_dev_reset(dev, 0);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3393}
3394EXPORT_SYMBOL_GPL(__pci_reset_function_locked);
3395
3396/**
3397 * pci_probe_reset_function - check whether the device can be safely reset
3398 * @dev: PCI device to reset
3399 *
3400 * Some devices allow an individual function to be reset without affecting
3401 * other functions in the same device.  The PCI device must be responsive
3402 * to PCI config space in order to use this function.
3403 *
3404 * Returns 0 if the device function can be reset or negative if the
3405 * device doesn't support resetting a single function.
3406 */
3407int pci_probe_reset_function(struct pci_dev *dev)
3408{
3409	return pci_dev_reset(dev, 1);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3410}
3411
3412/**
3413 * pci_reset_function - quiesce and reset a PCI device function
3414 * @dev: PCI device to reset
3415 *
3416 * Some devices allow an individual function to be reset without affecting
3417 * other functions in the same device.  The PCI device must be responsive
3418 * to PCI config space in order to use this function.
3419 *
3420 * This function does not just reset the PCI portion of a device, but
3421 * clears all the state associated with the device.  This function differs
3422 * from __pci_reset_function in that it saves and restores device state
3423 * over the reset.
3424 *
3425 * Returns 0 if the device function was successfully reset or negative if the
3426 * device doesn't support resetting a single function.
3427 */
3428int pci_reset_function(struct pci_dev *dev)
3429{
3430	int rc;
3431
3432	rc = pci_dev_reset(dev, 1);
3433	if (rc)
3434		return rc;
3435
 
3436	pci_dev_save_and_disable(dev);
3437
3438	rc = pci_dev_reset(dev, 0);
3439
3440	pci_dev_restore(dev);
 
3441
3442	return rc;
3443}
3444EXPORT_SYMBOL_GPL(pci_reset_function);
3445
3446/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3447 * pci_try_reset_function - quiesce and reset a PCI device function
3448 * @dev: PCI device to reset
3449 *
3450 * Same as above, except return -EAGAIN if unable to lock device.
3451 */
3452int pci_try_reset_function(struct pci_dev *dev)
3453{
3454	int rc;
3455
3456	rc = pci_dev_reset(dev, 1);
3457	if (rc)
3458		return rc;
 
 
3459
3460	pci_dev_save_and_disable(dev);
3461
3462	if (pci_dev_trylock(dev)) {
3463		rc = __pci_dev_reset(dev, 0);
3464		pci_dev_unlock(dev);
3465	} else
3466		rc = -EAGAIN;
3467
3468	pci_dev_restore(dev);
 
3469
3470	return rc;
3471}
3472EXPORT_SYMBOL_GPL(pci_try_reset_function);
3473
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3474/* Lock devices from the top of the tree down */
3475static void pci_bus_lock(struct pci_bus *bus)
3476{
3477	struct pci_dev *dev;
3478
3479	list_for_each_entry(dev, &bus->devices, bus_list) {
3480		pci_dev_lock(dev);
3481		if (dev->subordinate)
3482			pci_bus_lock(dev->subordinate);
3483	}
3484}
3485
3486/* Unlock devices from the bottom of the tree up */
3487static void pci_bus_unlock(struct pci_bus *bus)
3488{
3489	struct pci_dev *dev;
3490
3491	list_for_each_entry(dev, &bus->devices, bus_list) {
3492		if (dev->subordinate)
3493			pci_bus_unlock(dev->subordinate);
3494		pci_dev_unlock(dev);
3495	}
3496}
3497
3498/* Return 1 on successful lock, 0 on contention */
3499static int pci_bus_trylock(struct pci_bus *bus)
3500{
3501	struct pci_dev *dev;
3502
3503	list_for_each_entry(dev, &bus->devices, bus_list) {
3504		if (!pci_dev_trylock(dev))
3505			goto unlock;
3506		if (dev->subordinate) {
3507			if (!pci_bus_trylock(dev->subordinate)) {
3508				pci_dev_unlock(dev);
3509				goto unlock;
3510			}
3511		}
3512	}
3513	return 1;
3514
3515unlock:
3516	list_for_each_entry_continue_reverse(dev, &bus->devices, bus_list) {
3517		if (dev->subordinate)
3518			pci_bus_unlock(dev->subordinate);
3519		pci_dev_unlock(dev);
3520	}
3521	return 0;
3522}
3523
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3524/* Lock devices from the top of the tree down */
3525static void pci_slot_lock(struct pci_slot *slot)
3526{
3527	struct pci_dev *dev;
3528
3529	list_for_each_entry(dev, &slot->bus->devices, bus_list) {
3530		if (!dev->slot || dev->slot != slot)
3531			continue;
3532		pci_dev_lock(dev);
3533		if (dev->subordinate)
3534			pci_bus_lock(dev->subordinate);
3535	}
3536}
3537
3538/* Unlock devices from the bottom of the tree up */
3539static void pci_slot_unlock(struct pci_slot *slot)
3540{
3541	struct pci_dev *dev;
3542
3543	list_for_each_entry(dev, &slot->bus->devices, bus_list) {
3544		if (!dev->slot || dev->slot != slot)
3545			continue;
3546		if (dev->subordinate)
3547			pci_bus_unlock(dev->subordinate);
3548		pci_dev_unlock(dev);
3549	}
3550}
3551
3552/* Return 1 on successful lock, 0 on contention */
3553static int pci_slot_trylock(struct pci_slot *slot)
3554{
3555	struct pci_dev *dev;
3556
3557	list_for_each_entry(dev, &slot->bus->devices, bus_list) {
3558		if (!dev->slot || dev->slot != slot)
3559			continue;
3560		if (!pci_dev_trylock(dev))
3561			goto unlock;
3562		if (dev->subordinate) {
3563			if (!pci_bus_trylock(dev->subordinate)) {
3564				pci_dev_unlock(dev);
3565				goto unlock;
3566			}
3567		}
3568	}
3569	return 1;
3570
3571unlock:
3572	list_for_each_entry_continue_reverse(dev,
3573					     &slot->bus->devices, bus_list) {
3574		if (!dev->slot || dev->slot != slot)
3575			continue;
3576		if (dev->subordinate)
3577			pci_bus_unlock(dev->subordinate);
3578		pci_dev_unlock(dev);
3579	}
3580	return 0;
3581}
3582
3583/* Save and disable devices from the top of the tree down */
3584static void pci_bus_save_and_disable(struct pci_bus *bus)
 
 
 
3585{
3586	struct pci_dev *dev;
3587
3588	list_for_each_entry(dev, &bus->devices, bus_list) {
3589		pci_dev_save_and_disable(dev);
3590		if (dev->subordinate)
3591			pci_bus_save_and_disable(dev->subordinate);
3592	}
3593}
3594
3595/*
3596 * Restore devices from top of the tree down - parent bridges need to be
3597 * restored before we can get to subordinate devices.
 
3598 */
3599static void pci_bus_restore(struct pci_bus *bus)
3600{
3601	struct pci_dev *dev;
3602
3603	list_for_each_entry(dev, &bus->devices, bus_list) {
3604		pci_dev_restore(dev);
3605		if (dev->subordinate)
3606			pci_bus_restore(dev->subordinate);
3607	}
3608}
3609
3610/* Save and disable devices from the top of the tree down */
3611static void pci_slot_save_and_disable(struct pci_slot *slot)
 
 
 
3612{
3613	struct pci_dev *dev;
3614
3615	list_for_each_entry(dev, &slot->bus->devices, bus_list) {
3616		if (!dev->slot || dev->slot != slot)
3617			continue;
3618		pci_dev_save_and_disable(dev);
3619		if (dev->subordinate)
3620			pci_bus_save_and_disable(dev->subordinate);
3621	}
3622}
3623
3624/*
3625 * Restore devices from top of the tree down - parent bridges need to be
3626 * restored before we can get to subordinate devices.
 
3627 */
3628static void pci_slot_restore(struct pci_slot *slot)
3629{
3630	struct pci_dev *dev;
3631
3632	list_for_each_entry(dev, &slot->bus->devices, bus_list) {
3633		if (!dev->slot || dev->slot != slot)
3634			continue;
3635		pci_dev_restore(dev);
3636		if (dev->subordinate)
3637			pci_bus_restore(dev->subordinate);
3638	}
3639}
3640
3641static int pci_slot_reset(struct pci_slot *slot, int probe)
3642{
3643	int rc;
3644
3645	if (!slot)
3646		return -ENOTTY;
3647
3648	if (!probe)
3649		pci_slot_lock(slot);
3650
3651	might_sleep();
3652
3653	rc = pci_reset_hotplug_slot(slot->hotplug, probe);
3654
3655	if (!probe)
3656		pci_slot_unlock(slot);
3657
3658	return rc;
3659}
3660
3661/**
3662 * pci_probe_reset_slot - probe whether a PCI slot can be reset
3663 * @slot: PCI slot to probe
3664 *
3665 * Return 0 if slot can be reset, negative if a slot reset is not supported.
3666 */
3667int pci_probe_reset_slot(struct pci_slot *slot)
3668{
3669	return pci_slot_reset(slot, 1);
3670}
3671EXPORT_SYMBOL_GPL(pci_probe_reset_slot);
3672
3673/**
3674 * pci_reset_slot - reset a PCI slot
3675 * @slot: PCI slot to reset
3676 *
3677 * A PCI bus may host multiple slots, each slot may support a reset mechanism
3678 * independent of other slots.  For instance, some slots may support slot power
3679 * control.  In the case of a 1:1 bus to slot architecture, this function may
3680 * wrap the bus reset to avoid spurious slot related events such as hotplug.
3681 * Generally a slot reset should be attempted before a bus reset.  All of the
3682 * function of the slot and any subordinate buses behind the slot are reset
3683 * through this function.  PCI config space of all devices in the slot and
3684 * behind the slot is saved before and restored after reset.
3685 *
3686 * Return 0 on success, non-zero on error.
3687 */
3688int pci_reset_slot(struct pci_slot *slot)
3689{
3690	int rc;
3691
3692	rc = pci_slot_reset(slot, 1);
3693	if (rc)
3694		return rc;
3695
3696	pci_slot_save_and_disable(slot);
3697
3698	rc = pci_slot_reset(slot, 0);
3699
3700	pci_slot_restore(slot);
3701
3702	return rc;
3703}
3704EXPORT_SYMBOL_GPL(pci_reset_slot);
3705
3706/**
3707 * pci_try_reset_slot - Try to reset a PCI slot
3708 * @slot: PCI slot to reset
3709 *
3710 * Same as above except return -EAGAIN if the slot cannot be locked
3711 */
3712int pci_try_reset_slot(struct pci_slot *slot)
3713{
3714	int rc;
3715
3716	rc = pci_slot_reset(slot, 1);
3717	if (rc)
3718		return rc;
3719
3720	pci_slot_save_and_disable(slot);
3721
3722	if (pci_slot_trylock(slot)) {
 
3723		might_sleep();
3724		rc = pci_reset_hotplug_slot(slot->hotplug, 0);
 
3725		pci_slot_unlock(slot);
3726	} else
3727		rc = -EAGAIN;
3728
3729	pci_slot_restore(slot);
3730
3731	return rc;
3732}
3733EXPORT_SYMBOL_GPL(pci_try_reset_slot);
3734
3735static int pci_bus_reset(struct pci_bus *bus, int probe)
3736{
3737	if (!bus->self)
 
 
3738		return -ENOTTY;
3739
3740	if (probe)
3741		return 0;
3742
3743	pci_bus_lock(bus);
3744
3745	might_sleep();
3746
3747	pci_reset_bridge_secondary_bus(bus->self);
3748
3749	pci_bus_unlock(bus);
3750
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3751	return 0;
 
 
 
3752}
3753
3754/**
3755 * pci_probe_reset_bus - probe whether a PCI bus can be reset
3756 * @bus: PCI bus to probe
3757 *
3758 * Return 0 if bus can be reset, negative if a bus reset is not supported.
3759 */
3760int pci_probe_reset_bus(struct pci_bus *bus)
3761{
3762	return pci_bus_reset(bus, 1);
3763}
3764EXPORT_SYMBOL_GPL(pci_probe_reset_bus);
3765
3766/**
3767 * pci_reset_bus - reset a PCI bus
3768 * @bus: top level PCI bus to reset
3769 *
3770 * Do a bus reset on the given bus and any subordinate buses, saving
3771 * and restoring state of all devices.
3772 *
3773 * Return 0 on success, non-zero on error.
3774 */
3775int pci_reset_bus(struct pci_bus *bus)
3776{
3777	int rc;
3778
3779	rc = pci_bus_reset(bus, 1);
3780	if (rc)
3781		return rc;
3782
3783	pci_bus_save_and_disable(bus);
3784
3785	rc = pci_bus_reset(bus, 0);
3786
3787	pci_bus_restore(bus);
 
 
 
3788
3789	return rc;
3790}
3791EXPORT_SYMBOL_GPL(pci_reset_bus);
3792
3793/**
3794 * pci_try_reset_bus - Try to reset a PCI bus
3795 * @bus: top level PCI bus to reset
3796 *
3797 * Same as above except return -EAGAIN if the bus cannot be locked
3798 */
3799int pci_try_reset_bus(struct pci_bus *bus)
3800{
3801	int rc;
3802
3803	rc = pci_bus_reset(bus, 1);
3804	if (rc)
3805		return rc;
3806
3807	pci_bus_save_and_disable(bus);
3808
3809	if (pci_bus_trylock(bus)) {
3810		might_sleep();
3811		pci_reset_bridge_secondary_bus(bus->self);
3812		pci_bus_unlock(bus);
3813	} else
3814		rc = -EAGAIN;
3815
3816	pci_bus_restore(bus);
3817
3818	return rc;
3819}
3820EXPORT_SYMBOL_GPL(pci_try_reset_bus);
3821
3822/**
3823 * pcix_get_max_mmrbc - get PCI-X maximum designed memory read byte count
3824 * @dev: PCI device to query
3825 *
3826 * Returns mmrbc: maximum designed memory read count in bytes
3827 *    or appropriate error value.
3828 */
3829int pcix_get_max_mmrbc(struct pci_dev *dev)
3830{
3831	int cap;
3832	u32 stat;
3833
3834	cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
3835	if (!cap)
3836		return -EINVAL;
3837
3838	if (pci_read_config_dword(dev, cap + PCI_X_STATUS, &stat))
3839		return -EINVAL;
3840
3841	return 512 << ((stat & PCI_X_STATUS_MAX_READ) >> 21);
3842}
3843EXPORT_SYMBOL(pcix_get_max_mmrbc);
3844
3845/**
3846 * pcix_get_mmrbc - get PCI-X maximum memory read byte count
3847 * @dev: PCI device to query
3848 *
3849 * Returns mmrbc: maximum memory read count in bytes
3850 *    or appropriate error value.
3851 */
3852int pcix_get_mmrbc(struct pci_dev *dev)
3853{
3854	int cap;
3855	u16 cmd;
3856
3857	cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
3858	if (!cap)
3859		return -EINVAL;
3860
3861	if (pci_read_config_word(dev, cap + PCI_X_CMD, &cmd))
3862		return -EINVAL;
3863
3864	return 512 << ((cmd & PCI_X_CMD_MAX_READ) >> 2);
3865}
3866EXPORT_SYMBOL(pcix_get_mmrbc);
3867
3868/**
3869 * pcix_set_mmrbc - set PCI-X maximum memory read byte count
3870 * @dev: PCI device to query
3871 * @mmrbc: maximum memory read count in bytes
3872 *    valid values are 512, 1024, 2048, 4096
3873 *
3874 * If possible sets maximum memory read byte count, some bridges have erratas
3875 * that prevent this.
3876 */
3877int pcix_set_mmrbc(struct pci_dev *dev, int mmrbc)
3878{
3879	int cap;
3880	u32 stat, v, o;
3881	u16 cmd;
3882
3883	if (mmrbc < 512 || mmrbc > 4096 || !is_power_of_2(mmrbc))
3884		return -EINVAL;
3885
3886	v = ffs(mmrbc) - 10;
3887
3888	cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
3889	if (!cap)
3890		return -EINVAL;
3891
3892	if (pci_read_config_dword(dev, cap + PCI_X_STATUS, &stat))
3893		return -EINVAL;
3894
3895	if (v > (stat & PCI_X_STATUS_MAX_READ) >> 21)
3896		return -E2BIG;
3897
3898	if (pci_read_config_word(dev, cap + PCI_X_CMD, &cmd))
3899		return -EINVAL;
3900
3901	o = (cmd & PCI_X_CMD_MAX_READ) >> 2;
3902	if (o != v) {
3903		if (v > o && (dev->bus->bus_flags & PCI_BUS_FLAGS_NO_MMRBC))
3904			return -EIO;
3905
3906		cmd &= ~PCI_X_CMD_MAX_READ;
3907		cmd |= v << 2;
3908		if (pci_write_config_word(dev, cap + PCI_X_CMD, cmd))
3909			return -EIO;
3910	}
3911	return 0;
3912}
3913EXPORT_SYMBOL(pcix_set_mmrbc);
3914
3915/**
3916 * pcie_get_readrq - get PCI Express read request size
3917 * @dev: PCI device to query
3918 *
3919 * Returns maximum memory read request in bytes
3920 *    or appropriate error value.
3921 */
3922int pcie_get_readrq(struct pci_dev *dev)
3923{
3924	u16 ctl;
3925
3926	pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &ctl);
3927
3928	return 128 << ((ctl & PCI_EXP_DEVCTL_READRQ) >> 12);
3929}
3930EXPORT_SYMBOL(pcie_get_readrq);
3931
3932/**
3933 * pcie_set_readrq - set PCI Express maximum memory read request
3934 * @dev: PCI device to query
3935 * @rq: maximum memory read count in bytes
3936 *    valid values are 128, 256, 512, 1024, 2048, 4096
3937 *
3938 * If possible sets maximum memory read request in bytes
3939 */
3940int pcie_set_readrq(struct pci_dev *dev, int rq)
3941{
3942	u16 v;
3943
3944	if (rq < 128 || rq > 4096 || !is_power_of_2(rq))
3945		return -EINVAL;
3946
3947	/*
3948	 * If using the "performance" PCIe config, we clamp the
3949	 * read rq size to the max packet size to prevent the
3950	 * host bridge generating requests larger than we can
3951	 * cope with
3952	 */
3953	if (pcie_bus_config == PCIE_BUS_PERFORMANCE) {
3954		int mps = pcie_get_mps(dev);
3955
3956		if (mps < rq)
3957			rq = mps;
3958	}
3959
3960	v = (ffs(rq) - 8) << 12;
3961
3962	return pcie_capability_clear_and_set_word(dev, PCI_EXP_DEVCTL,
3963						  PCI_EXP_DEVCTL_READRQ, v);
3964}
3965EXPORT_SYMBOL(pcie_set_readrq);
3966
3967/**
3968 * pcie_get_mps - get PCI Express maximum payload size
3969 * @dev: PCI device to query
3970 *
3971 * Returns maximum payload size in bytes
3972 */
3973int pcie_get_mps(struct pci_dev *dev)
3974{
3975	u16 ctl;
3976
3977	pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &ctl);
3978
3979	return 128 << ((ctl & PCI_EXP_DEVCTL_PAYLOAD) >> 5);
3980}
3981EXPORT_SYMBOL(pcie_get_mps);
3982
3983/**
3984 * pcie_set_mps - set PCI Express maximum payload size
3985 * @dev: PCI device to query
3986 * @mps: maximum payload size in bytes
3987 *    valid values are 128, 256, 512, 1024, 2048, 4096
3988 *
3989 * If possible sets maximum payload size
3990 */
3991int pcie_set_mps(struct pci_dev *dev, int mps)
3992{
3993	u16 v;
3994
3995	if (mps < 128 || mps > 4096 || !is_power_of_2(mps))
3996		return -EINVAL;
3997
3998	v = ffs(mps) - 8;
3999	if (v > dev->pcie_mpss)
4000		return -EINVAL;
4001	v <<= 5;
4002
4003	return pcie_capability_clear_and_set_word(dev, PCI_EXP_DEVCTL,
4004						  PCI_EXP_DEVCTL_PAYLOAD, v);
4005}
4006EXPORT_SYMBOL(pcie_set_mps);
4007
4008/**
4009 * pcie_get_minimum_link - determine minimum link settings of a PCI device
 
4010 * @dev: PCI device to query
4011 * @speed: storage for minimum speed
4012 * @width: storage for minimum width
4013 *
4014 * This function will walk up the PCI device chain and determine the minimum
4015 * link width and speed of the device.
4016 */
4017int pcie_get_minimum_link(struct pci_dev *dev, enum pci_bus_speed *speed,
4018			  enum pcie_link_width *width)
4019{
4020	int ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
4021
4022	*speed = PCI_SPEED_UNKNOWN;
4023	*width = PCIE_LNK_WIDTH_UNKNOWN;
4024
4025	while (dev) {
4026		u16 lnksta;
4027		enum pci_bus_speed next_speed;
4028		enum pcie_link_width next_width;
4029
4030		ret = pcie_capability_read_word(dev, PCI_EXP_LNKSTA, &lnksta);
4031		if (ret)
4032			return ret;
4033
4034		next_speed = pcie_link_speed[lnksta & PCI_EXP_LNKSTA_CLS];
4035		next_width = (lnksta & PCI_EXP_LNKSTA_NLW) >>
4036			PCI_EXP_LNKSTA_NLW_SHIFT;
4037
4038		if (next_speed < *speed)
4039			*speed = next_speed;
4040
4041		if (next_width < *width)
4042			*width = next_width;
 
 
 
 
 
 
 
 
 
4043
4044		dev = dev->bus->self;
4045	}
4046
4047	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4048}
4049EXPORT_SYMBOL(pcie_get_minimum_link);
4050
4051/**
4052 * pci_select_bars - Make BAR mask from the type of resource
4053 * @dev: the PCI device for which BAR mask is made
4054 * @flags: resource type mask to be selected
4055 *
4056 * This helper routine makes bar mask from the type of resource.
4057 */
4058int pci_select_bars(struct pci_dev *dev, unsigned long flags)
4059{
4060	int i, bars = 0;
4061	for (i = 0; i < PCI_NUM_RESOURCES; i++)
4062		if (pci_resource_flags(dev, i) & flags)
4063			bars |= (1 << i);
4064	return bars;
4065}
4066
4067/**
4068 * pci_resource_bar - get position of the BAR associated with a resource
4069 * @dev: the PCI device
4070 * @resno: the resource number
4071 * @type: the BAR type to be filled in
4072 *
4073 * Returns BAR position in config space, or 0 if the BAR is invalid.
4074 */
4075int pci_resource_bar(struct pci_dev *dev, int resno, enum pci_bar_type *type)
4076{
4077	int reg;
4078
4079	if (resno < PCI_ROM_RESOURCE) {
4080		*type = pci_bar_unknown;
4081		return PCI_BASE_ADDRESS_0 + 4 * resno;
4082	} else if (resno == PCI_ROM_RESOURCE) {
4083		*type = pci_bar_mem32;
4084		return dev->rom_base_reg;
4085	} else if (resno < PCI_BRIDGE_RESOURCES) {
4086		/* device specific resource */
4087		reg = pci_iov_resource_bar(dev, resno, type);
4088		if (reg)
4089			return reg;
4090	}
4091
4092	dev_err(&dev->dev, "BAR %d: invalid resource\n", resno);
4093	return 0;
4094}
4095
4096/* Some architectures require additional programming to enable VGA */
4097static arch_set_vga_state_t arch_set_vga_state;
4098
4099void __init pci_register_set_vga_state(arch_set_vga_state_t func)
4100{
4101	arch_set_vga_state = func;	/* NULL disables */
4102}
4103
4104static int pci_set_vga_state_arch(struct pci_dev *dev, bool decode,
4105		      unsigned int command_bits, u32 flags)
4106{
4107	if (arch_set_vga_state)
4108		return arch_set_vga_state(dev, decode, command_bits,
4109						flags);
4110	return 0;
4111}
4112
4113/**
4114 * pci_set_vga_state - set VGA decode state on device and parents if requested
4115 * @dev: the PCI device
4116 * @decode: true = enable decoding, false = disable decoding
4117 * @command_bits: PCI_COMMAND_IO and/or PCI_COMMAND_MEMORY
4118 * @flags: traverse ancestors and change bridges
4119 * CHANGE_BRIDGE_ONLY / CHANGE_BRIDGE
4120 */
4121int pci_set_vga_state(struct pci_dev *dev, bool decode,
4122		      unsigned int command_bits, u32 flags)
4123{
4124	struct pci_bus *bus;
4125	struct pci_dev *bridge;
4126	u16 cmd;
4127	int rc;
4128
4129	WARN_ON((flags & PCI_VGA_STATE_CHANGE_DECODES) & (command_bits & ~(PCI_COMMAND_IO|PCI_COMMAND_MEMORY)));
4130
4131	/* ARCH specific VGA enables */
4132	rc = pci_set_vga_state_arch(dev, decode, command_bits, flags);
4133	if (rc)
4134		return rc;
4135
4136	if (flags & PCI_VGA_STATE_CHANGE_DECODES) {
4137		pci_read_config_word(dev, PCI_COMMAND, &cmd);
4138		if (decode == true)
4139			cmd |= command_bits;
4140		else
4141			cmd &= ~command_bits;
4142		pci_write_config_word(dev, PCI_COMMAND, cmd);
4143	}
4144
4145	if (!(flags & PCI_VGA_STATE_CHANGE_BRIDGE))
4146		return 0;
4147
4148	bus = dev->bus;
4149	while (bus) {
4150		bridge = bus->self;
4151		if (bridge) {
4152			pci_read_config_word(bridge, PCI_BRIDGE_CONTROL,
4153					     &cmd);
4154			if (decode == true)
4155				cmd |= PCI_BRIDGE_CTL_VGA;
4156			else
4157				cmd &= ~PCI_BRIDGE_CTL_VGA;
4158			pci_write_config_word(bridge, PCI_BRIDGE_CONTROL,
4159					      cmd);
4160		}
4161		bus = bus->parent;
4162	}
4163	return 0;
4164}
4165
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4166bool pci_device_is_present(struct pci_dev *pdev)
4167{
4168	u32 v;
4169
 
 
4170	return pci_bus_read_dev_vendor_id(pdev->bus, pdev->devfn, &v, 0);
4171}
4172EXPORT_SYMBOL_GPL(pci_device_is_present);
4173
4174#define RESOURCE_ALIGNMENT_PARAM_SIZE COMMAND_LINE_SIZE
4175static char resource_alignment_param[RESOURCE_ALIGNMENT_PARAM_SIZE] = {0};
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4176static DEFINE_SPINLOCK(resource_alignment_lock);
4177
4178/**
4179 * pci_specified_resource_alignment - get resource alignment specified by user.
4180 * @dev: the PCI device to get
 
4181 *
4182 * RETURNS: Resource alignment if it is specified.
4183 *          Zero if it is not specified.
4184 */
4185static resource_size_t pci_specified_resource_alignment(struct pci_dev *dev)
 
4186{
4187	int seg, bus, slot, func, align_order, count;
4188	resource_size_t align = 0;
4189	char *p;
 
4190
4191	spin_lock(&resource_alignment_lock);
4192	p = resource_alignment_param;
 
 
 
 
 
 
 
 
4193	while (*p) {
4194		count = 0;
4195		if (sscanf(p, "%d%n", &align_order, &count) == 1 &&
4196							p[count] == '@') {
4197			p += count + 1;
4198		} else {
4199			align_order = -1;
4200		}
4201		if (sscanf(p, "%x:%x:%x.%x%n",
4202			&seg, &bus, &slot, &func, &count) != 4) {
4203			seg = 0;
4204			if (sscanf(p, "%x:%x.%x%n",
4205					&bus, &slot, &func, &count) != 3) {
4206				/* Invalid format */
4207				printk(KERN_ERR "PCI: Can't parse resource_alignment parameter: %s\n",
4208					p);
4209				break;
4210			}
4211		}
4212		p += count;
4213		if (seg == pci_domain_nr(dev->bus) &&
4214			bus == dev->bus->number &&
4215			slot == PCI_SLOT(dev->devfn) &&
4216			func == PCI_FUNC(dev->devfn)) {
4217			if (align_order == -1) {
4218				align = PAGE_SIZE;
4219			} else {
4220				align = 1 << align_order;
4221			}
4222			/* Found */
 
 
4223			break;
4224		}
 
4225		if (*p != ';' && *p != ',') {
4226			/* End of param or invalid format */
4227			break;
4228		}
4229		p++;
4230	}
 
4231	spin_unlock(&resource_alignment_lock);
4232	return align;
4233}
4234
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4235/*
4236 * This function disables memory decoding and releases memory resources
4237 * of the device specified by kernel's boot parameter 'pci=resource_alignment='.
4238 * It also rounds up size to specified alignment.
4239 * Later on, the kernel will assign page-aligned memory resource back
4240 * to the device.
4241 */
4242void pci_reassigndev_resource_alignment(struct pci_dev *dev)
4243{
4244	int i;
4245	struct resource *r;
4246	resource_size_t align, size;
4247	u16 command;
 
 
 
 
 
 
 
 
 
 
4248
4249	/* check if specified PCI is target device to reassign */
4250	align = pci_specified_resource_alignment(dev);
4251	if (!align)
4252		return;
4253
4254	if (dev->hdr_type == PCI_HEADER_TYPE_NORMAL &&
4255	    (dev->class >> 8) == PCI_CLASS_BRIDGE_HOST) {
4256		dev_warn(&dev->dev,
4257			"Can't reassign resources to host bridge.\n");
4258		return;
4259	}
4260
4261	dev_info(&dev->dev,
4262		"Disabling memory decoding and releasing memory resources.\n");
4263	pci_read_config_word(dev, PCI_COMMAND, &command);
4264	command &= ~PCI_COMMAND_MEMORY;
4265	pci_write_config_word(dev, PCI_COMMAND, command);
4266
4267	for (i = 0; i < PCI_BRIDGE_RESOURCES; i++) {
4268		r = &dev->resource[i];
4269		if (!(r->flags & IORESOURCE_MEM))
4270			continue;
4271		size = resource_size(r);
4272		if (size < align) {
4273			size = align;
4274			dev_info(&dev->dev,
4275				"Rounding up size of resource #%d to %#llx.\n",
4276				i, (unsigned long long)size);
4277		}
4278		r->flags |= IORESOURCE_UNSET;
4279		r->end = size - 1;
4280		r->start = 0;
4281	}
4282	/* Need to disable bridge's resource window,
4283	 * to enable the kernel to reassign new resource
4284	 * window later on.
4285	 */
4286	if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE &&
4287	    (dev->class >> 8) == PCI_CLASS_BRIDGE_PCI) {
4288		for (i = PCI_BRIDGE_RESOURCES; i < PCI_NUM_RESOURCES; i++) {
4289			r = &dev->resource[i];
4290			if (!(r->flags & IORESOURCE_MEM))
4291				continue;
4292			r->flags |= IORESOURCE_UNSET;
4293			r->end = resource_size(r) - 1;
4294			r->start = 0;
4295		}
4296		pci_disable_bridge_window(dev);
4297	}
4298}
4299
4300static ssize_t pci_set_resource_alignment_param(const char *buf, size_t count)
4301{
4302	if (count > RESOURCE_ALIGNMENT_PARAM_SIZE - 1)
4303		count = RESOURCE_ALIGNMENT_PARAM_SIZE - 1;
4304	spin_lock(&resource_alignment_lock);
4305	strncpy(resource_alignment_param, buf, count);
4306	resource_alignment_param[count] = '\0';
4307	spin_unlock(&resource_alignment_lock);
 
 
 
 
 
 
 
 
 
 
 
4308	return count;
4309}
4310
4311static ssize_t pci_get_resource_alignment_param(char *buf, size_t size)
 
4312{
4313	size_t count;
 
 
 
 
4314	spin_lock(&resource_alignment_lock);
4315	count = snprintf(buf, size, "%s", resource_alignment_param);
 
4316	spin_unlock(&resource_alignment_lock);
4317	return count;
4318}
4319
4320static ssize_t pci_resource_alignment_show(struct bus_type *bus, char *buf)
4321{
4322	return pci_get_resource_alignment_param(buf, PAGE_SIZE);
4323}
4324
4325static ssize_t pci_resource_alignment_store(struct bus_type *bus,
4326					const char *buf, size_t count)
4327{
4328	return pci_set_resource_alignment_param(buf, count);
4329}
4330
4331BUS_ATTR(resource_alignment, 0644, pci_resource_alignment_show,
4332					pci_resource_alignment_store);
4333
4334static int __init pci_resource_alignment_sysfs_init(void)
4335{
4336	return bus_create_file(&pci_bus_type,
4337					&bus_attr_resource_alignment);
4338}
4339
4340late_initcall(pci_resource_alignment_sysfs_init);
4341
4342static void pci_no_domains(void)
4343{
4344#ifdef CONFIG_PCI_DOMAINS
4345	pci_domains_supported = 0;
4346#endif
4347}
4348
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4349/**
4350 * pci_ext_cfg_avail - can we access extended PCI config space?
4351 *
4352 * Returns 1 if we can access PCI extended config space (offsets
4353 * greater than 0xff). This is the default implementation. Architecture
4354 * implementations can override this.
4355 */
4356int __weak pci_ext_cfg_avail(void)
4357{
4358	return 1;
4359}
4360
4361void __weak pci_fixup_cardbus(struct pci_bus *bus)
4362{
4363}
4364EXPORT_SYMBOL(pci_fixup_cardbus);
4365
4366static int __init pci_setup(char *str)
4367{
4368	while (str) {
4369		char *k = strchr(str, ',');
4370		if (k)
4371			*k++ = 0;
4372		if (*str && (str = pcibios_setup(str)) && *str) {
4373			if (!strcmp(str, "nomsi")) {
4374				pci_no_msi();
 
 
 
4375			} else if (!strcmp(str, "noaer")) {
4376				pci_no_aer();
 
 
4377			} else if (!strncmp(str, "realloc=", 8)) {
4378				pci_realloc_get_opt(str + 8);
4379			} else if (!strncmp(str, "realloc", 7)) {
4380				pci_realloc_get_opt("on");
4381			} else if (!strcmp(str, "nodomains")) {
4382				pci_no_domains();
4383			} else if (!strncmp(str, "noari", 5)) {
4384				pcie_ari_disabled = true;
4385			} else if (!strncmp(str, "cbiosize=", 9)) {
4386				pci_cardbus_io_size = memparse(str + 9, &str);
4387			} else if (!strncmp(str, "cbmemsize=", 10)) {
4388				pci_cardbus_mem_size = memparse(str + 10, &str);
4389			} else if (!strncmp(str, "resource_alignment=", 19)) {
4390				pci_set_resource_alignment_param(str + 19,
4391							strlen(str + 19));
4392			} else if (!strncmp(str, "ecrc=", 5)) {
4393				pcie_ecrc_get_policy(str + 5);
4394			} else if (!strncmp(str, "hpiosize=", 9)) {
4395				pci_hotplug_io_size = memparse(str + 9, &str);
4396			} else if (!strncmp(str, "hpmemsize=", 10)) {
4397				pci_hotplug_mem_size = memparse(str + 10, &str);
 
 
 
 
 
4398			} else if (!strncmp(str, "pcie_bus_tune_off", 17)) {
4399				pcie_bus_config = PCIE_BUS_TUNE_OFF;
4400			} else if (!strncmp(str, "pcie_bus_safe", 13)) {
4401				pcie_bus_config = PCIE_BUS_SAFE;
4402			} else if (!strncmp(str, "pcie_bus_perf", 13)) {
4403				pcie_bus_config = PCIE_BUS_PERFORMANCE;
4404			} else if (!strncmp(str, "pcie_bus_peer2peer", 18)) {
4405				pcie_bus_config = PCIE_BUS_PEER2PEER;
4406			} else if (!strncmp(str, "pcie_scan_all", 13)) {
4407				pci_add_flags(PCI_SCAN_ALL_PCIE_DEVS);
 
 
4408			} else {
4409				printk(KERN_ERR "PCI: Unknown option `%s'\n",
4410						str);
4411			}
4412		}
4413		str = k;
4414	}
4415	return 0;
4416}
4417early_param("pci", pci_setup);
4418
4419EXPORT_SYMBOL(pci_reenable_device);
4420EXPORT_SYMBOL(pci_enable_device_io);
4421EXPORT_SYMBOL(pci_enable_device_mem);
4422EXPORT_SYMBOL(pci_enable_device);
4423EXPORT_SYMBOL(pcim_enable_device);
4424EXPORT_SYMBOL(pcim_pin_device);
4425EXPORT_SYMBOL(pci_disable_device);
4426EXPORT_SYMBOL(pci_find_capability);
4427EXPORT_SYMBOL(pci_bus_find_capability);
4428EXPORT_SYMBOL(pci_release_regions);
4429EXPORT_SYMBOL(pci_request_regions);
4430EXPORT_SYMBOL(pci_request_regions_exclusive);
4431EXPORT_SYMBOL(pci_release_region);
4432EXPORT_SYMBOL(pci_request_region);
4433EXPORT_SYMBOL(pci_request_region_exclusive);
4434EXPORT_SYMBOL(pci_release_selected_regions);
4435EXPORT_SYMBOL(pci_request_selected_regions);
4436EXPORT_SYMBOL(pci_request_selected_regions_exclusive);
4437EXPORT_SYMBOL(pci_set_master);
4438EXPORT_SYMBOL(pci_clear_master);
4439EXPORT_SYMBOL(pci_set_mwi);
4440EXPORT_SYMBOL(pci_try_set_mwi);
4441EXPORT_SYMBOL(pci_clear_mwi);
4442EXPORT_SYMBOL_GPL(pci_intx);
4443EXPORT_SYMBOL(pci_assign_resource);
4444EXPORT_SYMBOL(pci_find_parent_resource);
4445EXPORT_SYMBOL(pci_select_bars);
4446
4447EXPORT_SYMBOL(pci_set_power_state);
4448EXPORT_SYMBOL(pci_save_state);
4449EXPORT_SYMBOL(pci_restore_state);
4450EXPORT_SYMBOL(pci_pme_capable);
4451EXPORT_SYMBOL(pci_pme_active);
4452EXPORT_SYMBOL(pci_wake_from_d3);
4453EXPORT_SYMBOL(pci_prepare_to_sleep);
4454EXPORT_SYMBOL(pci_back_from_sleep);
4455EXPORT_SYMBOL_GPL(pci_set_pcie_reset_state);