Linux Audio

Check our new training course

Loading...
v6.8
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * PCI detection and setup code
   4 */
   5
   6#include <linux/kernel.h>
   7#include <linux/delay.h>
   8#include <linux/init.h>
   9#include <linux/pci.h>
  10#include <linux/msi.h>
  11#include <linux/of_pci.h>
  12#include <linux/pci_hotplug.h>
  13#include <linux/slab.h>
  14#include <linux/module.h>
  15#include <linux/cpumask.h>
  16#include <linux/aer.h>
  17#include <linux/acpi.h>
  18#include <linux/hypervisor.h>
  19#include <linux/irqdomain.h>
  20#include <linux/pm_runtime.h>
  21#include <linux/bitfield.h>
  22#include "pci.h"
  23
  24#define CARDBUS_LATENCY_TIMER	176	/* secondary latency timer */
  25#define CARDBUS_RESERVE_BUSNR	3
  26
  27static struct resource busn_resource = {
  28	.name	= "PCI busn",
  29	.start	= 0,
  30	.end	= 255,
  31	.flags	= IORESOURCE_BUS,
  32};
  33
  34/* Ugh.  Need to stop exporting this to modules. */
  35LIST_HEAD(pci_root_buses);
  36EXPORT_SYMBOL(pci_root_buses);
  37
  38static LIST_HEAD(pci_domain_busn_res_list);
  39
  40struct pci_domain_busn_res {
  41	struct list_head list;
  42	struct resource res;
  43	int domain_nr;
  44};
  45
  46static struct resource *get_pci_domain_busn_res(int domain_nr)
  47{
  48	struct pci_domain_busn_res *r;
  49
  50	list_for_each_entry(r, &pci_domain_busn_res_list, list)
  51		if (r->domain_nr == domain_nr)
  52			return &r->res;
  53
  54	r = kzalloc(sizeof(*r), GFP_KERNEL);
  55	if (!r)
  56		return NULL;
  57
  58	r->domain_nr = domain_nr;
  59	r->res.start = 0;
  60	r->res.end = 0xff;
  61	r->res.flags = IORESOURCE_BUS | IORESOURCE_PCI_FIXED;
  62
  63	list_add_tail(&r->list, &pci_domain_busn_res_list);
  64
  65	return &r->res;
  66}
  67
 
 
 
 
 
  68/*
  69 * Some device drivers need know if PCI is initiated.
  70 * Basically, we think PCI is not initiated when there
  71 * is no device to be found on the pci_bus_type.
  72 */
  73int no_pci_devices(void)
  74{
  75	struct device *dev;
  76	int no_devices;
  77
  78	dev = bus_find_next_device(&pci_bus_type, NULL);
  79	no_devices = (dev == NULL);
  80	put_device(dev);
  81	return no_devices;
  82}
  83EXPORT_SYMBOL(no_pci_devices);
  84
  85/*
  86 * PCI Bus Class
  87 */
  88static void release_pcibus_dev(struct device *dev)
  89{
  90	struct pci_bus *pci_bus = to_pci_bus(dev);
  91
  92	put_device(pci_bus->bridge);
 
  93	pci_bus_remove_resources(pci_bus);
  94	pci_release_bus_of_node(pci_bus);
  95	kfree(pci_bus);
  96}
  97
  98static struct class pcibus_class = {
  99	.name		= "pci_bus",
 100	.dev_release	= &release_pcibus_dev,
 101	.dev_groups	= pcibus_groups,
 102};
 103
 104static int __init pcibus_class_init(void)
 105{
 106	return class_register(&pcibus_class);
 107}
 108postcore_initcall(pcibus_class_init);
 109
 110static u64 pci_size(u64 base, u64 maxbase, u64 mask)
 111{
 112	u64 size = mask & maxbase;	/* Find the significant bits */
 113	if (!size)
 114		return 0;
 115
 116	/*
 117	 * Get the lowest of them to find the decode size, and from that
 118	 * the extent.
 119	 */
 120	size = size & ~(size-1);
 121
 122	/*
 123	 * base == maxbase can be valid only if the BAR has already been
 124	 * programmed with all 1s.
 125	 */
 126	if (base == maxbase && ((base | (size - 1)) & mask) != mask)
 127		return 0;
 128
 129	return size;
 130}
 131
 132static inline unsigned long decode_bar(struct pci_dev *dev, u32 bar)
 133{
 134	u32 mem_type;
 135	unsigned long flags;
 136
 137	if ((bar & PCI_BASE_ADDRESS_SPACE) == PCI_BASE_ADDRESS_SPACE_IO) {
 138		flags = bar & ~PCI_BASE_ADDRESS_IO_MASK;
 139		flags |= IORESOURCE_IO;
 140		return flags;
 141	}
 142
 143	flags = bar & ~PCI_BASE_ADDRESS_MEM_MASK;
 144	flags |= IORESOURCE_MEM;
 145	if (flags & PCI_BASE_ADDRESS_MEM_PREFETCH)
 146		flags |= IORESOURCE_PREFETCH;
 147
 148	mem_type = bar & PCI_BASE_ADDRESS_MEM_TYPE_MASK;
 149	switch (mem_type) {
 150	case PCI_BASE_ADDRESS_MEM_TYPE_32:
 151		break;
 152	case PCI_BASE_ADDRESS_MEM_TYPE_1M:
 153		/* 1M mem BAR treated as 32-bit BAR */
 154		break;
 155	case PCI_BASE_ADDRESS_MEM_TYPE_64:
 156		flags |= IORESOURCE_MEM_64;
 157		break;
 158	default:
 159		/* mem unknown type treated as 32-bit BAR */
 160		break;
 161	}
 162	return flags;
 163}
 164
 165#define PCI_COMMAND_DECODE_ENABLE	(PCI_COMMAND_MEMORY | PCI_COMMAND_IO)
 166
 167/**
 168 * __pci_read_base - Read a PCI BAR
 169 * @dev: the PCI device
 170 * @type: type of the BAR
 171 * @res: resource buffer to be filled in
 172 * @pos: BAR position in the config space
 173 *
 174 * Returns 1 if the BAR is 64-bit, or 0 if 32-bit.
 175 */
 176int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type,
 177		    struct resource *res, unsigned int pos)
 178{
 179	u32 l = 0, sz = 0, mask;
 180	u64 l64, sz64, mask64;
 181	u16 orig_cmd;
 182	struct pci_bus_region region, inverted_region;
 183	const char *res_name = pci_resource_name(dev, res - dev->resource);
 184
 185	mask = type ? PCI_ROM_ADDRESS_MASK : ~0;
 186
 187	/* No printks while decoding is disabled! */
 188	if (!dev->mmio_always_on) {
 189		pci_read_config_word(dev, PCI_COMMAND, &orig_cmd);
 190		if (orig_cmd & PCI_COMMAND_DECODE_ENABLE) {
 191			pci_write_config_word(dev, PCI_COMMAND,
 192				orig_cmd & ~PCI_COMMAND_DECODE_ENABLE);
 193		}
 194	}
 195
 196	res->name = pci_name(dev);
 197
 198	pci_read_config_dword(dev, pos, &l);
 199	pci_write_config_dword(dev, pos, l | mask);
 200	pci_read_config_dword(dev, pos, &sz);
 201	pci_write_config_dword(dev, pos, l);
 202
 203	/*
 204	 * All bits set in sz means the device isn't working properly.
 205	 * If the BAR isn't implemented, all bits must be 0.  If it's a
 206	 * memory BAR or a ROM, bit 0 must be clear; if it's an io BAR, bit
 207	 * 1 must be clear.
 208	 */
 209	if (PCI_POSSIBLE_ERROR(sz))
 210		sz = 0;
 211
 212	/*
 213	 * I don't know how l can have all bits set.  Copied from old code.
 214	 * Maybe it fixes a bug on some ancient platform.
 215	 */
 216	if (PCI_POSSIBLE_ERROR(l))
 217		l = 0;
 218
 219	if (type == pci_bar_unknown) {
 220		res->flags = decode_bar(dev, l);
 221		res->flags |= IORESOURCE_SIZEALIGN;
 222		if (res->flags & IORESOURCE_IO) {
 223			l64 = l & PCI_BASE_ADDRESS_IO_MASK;
 224			sz64 = sz & PCI_BASE_ADDRESS_IO_MASK;
 225			mask64 = PCI_BASE_ADDRESS_IO_MASK & (u32)IO_SPACE_LIMIT;
 226		} else {
 227			l64 = l & PCI_BASE_ADDRESS_MEM_MASK;
 228			sz64 = sz & PCI_BASE_ADDRESS_MEM_MASK;
 229			mask64 = (u32)PCI_BASE_ADDRESS_MEM_MASK;
 230		}
 231	} else {
 232		if (l & PCI_ROM_ADDRESS_ENABLE)
 233			res->flags |= IORESOURCE_ROM_ENABLE;
 234		l64 = l & PCI_ROM_ADDRESS_MASK;
 235		sz64 = sz & PCI_ROM_ADDRESS_MASK;
 236		mask64 = PCI_ROM_ADDRESS_MASK;
 237	}
 238
 239	if (res->flags & IORESOURCE_MEM_64) {
 
 
 
 
 240		pci_read_config_dword(dev, pos + 4, &l);
 241		pci_write_config_dword(dev, pos + 4, ~0);
 242		pci_read_config_dword(dev, pos + 4, &sz);
 243		pci_write_config_dword(dev, pos + 4, l);
 244
 245		l64 |= ((u64)l << 32);
 246		sz64 |= ((u64)sz << 32);
 247		mask64 |= ((u64)~0 << 32);
 248	}
 249
 250	if (!dev->mmio_always_on && (orig_cmd & PCI_COMMAND_DECODE_ENABLE))
 251		pci_write_config_word(dev, PCI_COMMAND, orig_cmd);
 252
 253	if (!sz64)
 254		goto fail;
 255
 256	sz64 = pci_size(l64, sz64, mask64);
 257	if (!sz64) {
 258		pci_info(dev, FW_BUG "%s: invalid; can't size\n", res_name);
 259		goto fail;
 260	}
 261
 262	if (res->flags & IORESOURCE_MEM_64) {
 263		if ((sizeof(pci_bus_addr_t) < 8 || sizeof(resource_size_t) < 8)
 264		    && sz64 > 0x100000000ULL) {
 265			res->flags |= IORESOURCE_UNSET | IORESOURCE_DISABLED;
 266			res->start = 0;
 267			res->end = 0;
 268			pci_err(dev, "%s: can't handle BAR larger than 4GB (size %#010llx)\n",
 269				res_name, (unsigned long long)sz64);
 270			goto out;
 271		}
 272
 273		if ((sizeof(pci_bus_addr_t) < 8) && l) {
 274			/* Above 32-bit boundary; try to reallocate */
 
 
 275			res->flags |= IORESOURCE_UNSET;
 276			res->start = 0;
 277			res->end = sz64 - 1;
 278			pci_info(dev, "%s: can't handle BAR above 4GB (bus address %#010llx)\n",
 279				 res_name, (unsigned long long)l64);
 280			goto out;
 
 281		}
 282	}
 
 
 
 
 283
 284	region.start = l64;
 285	region.end = l64 + sz64 - 1;
 
 286
 287	pcibios_bus_to_resource(dev->bus, res, &region);
 288	pcibios_resource_to_bus(dev->bus, &inverted_region, res);
 289
 290	/*
 291	 * If "A" is a BAR value (a bus address), "bus_to_resource(A)" is
 292	 * the corresponding resource address (the physical address used by
 293	 * the CPU.  Converting that resource address back to a bus address
 294	 * should yield the original BAR value:
 295	 *
 296	 *     resource_to_bus(bus_to_resource(A)) == A
 297	 *
 298	 * If it doesn't, CPU accesses to "bus_to_resource(A)" will not
 299	 * be claimed by the device.
 300	 */
 301	if (inverted_region.start != region.start) {
 
 
 302		res->flags |= IORESOURCE_UNSET;
 
 303		res->start = 0;
 304		res->end = region.end - region.start;
 305		pci_info(dev, "%s: initial BAR value %#010llx invalid\n",
 306			 res_name, (unsigned long long)region.start);
 307	}
 308
 309	goto out;
 310
 311
 312fail:
 313	res->flags = 0;
 314out:
 315	if (res->flags)
 316		pci_info(dev, "%s %pR\n", res_name, res);
 
 
 
 
 
 
 317
 318	return (res->flags & IORESOURCE_MEM_64) ? 1 : 0;
 319}
 320
 321static void pci_read_bases(struct pci_dev *dev, unsigned int howmany, int rom)
 322{
 323	unsigned int pos, reg;
 324
 325	if (dev->non_compliant_bars)
 326		return;
 327
 328	/* Per PCIe r4.0, sec 9.3.4.1.11, the VF BARs are all RO Zero */
 329	if (dev->is_virtfn)
 330		return;
 331
 332	for (pos = 0; pos < howmany; pos++) {
 333		struct resource *res = &dev->resource[pos];
 334		reg = PCI_BASE_ADDRESS_0 + (pos << 2);
 335		pos += __pci_read_base(dev, pci_bar_unknown, res, reg);
 336	}
 337
 338	if (rom) {
 339		struct resource *res = &dev->resource[PCI_ROM_RESOURCE];
 340		dev->rom_base_reg = rom;
 341		res->flags = IORESOURCE_MEM | IORESOURCE_PREFETCH |
 342				IORESOURCE_READONLY | IORESOURCE_SIZEALIGN;
 
 343		__pci_read_base(dev, pci_bar_mem32, res, rom);
 344	}
 345}
 346
 347static void pci_read_bridge_io(struct pci_dev *dev, struct resource *res,
 348			       bool log)
 349{
 
 350	u8 io_base_lo, io_limit_lo;
 351	unsigned long io_mask, io_granularity, base, limit;
 352	struct pci_bus_region region;
 
 353
 354	io_mask = PCI_IO_RANGE_MASK;
 355	io_granularity = 0x1000;
 356	if (dev->io_window_1k) {
 357		/* Support 1K I/O space granularity */
 358		io_mask = PCI_IO_1K_RANGE_MASK;
 359		io_granularity = 0x400;
 360	}
 361
 
 362	pci_read_config_byte(dev, PCI_IO_BASE, &io_base_lo);
 363	pci_read_config_byte(dev, PCI_IO_LIMIT, &io_limit_lo);
 364	base = (io_base_lo & io_mask) << 8;
 365	limit = (io_limit_lo & io_mask) << 8;
 366
 367	if ((io_base_lo & PCI_IO_RANGE_TYPE_MASK) == PCI_IO_RANGE_TYPE_32) {
 368		u16 io_base_hi, io_limit_hi;
 369
 370		pci_read_config_word(dev, PCI_IO_BASE_UPPER16, &io_base_hi);
 371		pci_read_config_word(dev, PCI_IO_LIMIT_UPPER16, &io_limit_hi);
 372		base |= ((unsigned long) io_base_hi << 16);
 373		limit |= ((unsigned long) io_limit_hi << 16);
 374	}
 375
 376	if (base <= limit) {
 377		res->flags = (io_base_lo & PCI_IO_RANGE_TYPE_MASK) | IORESOURCE_IO;
 378		region.start = base;
 379		region.end = limit + io_granularity - 1;
 380		pcibios_bus_to_resource(dev->bus, res, &region);
 381		if (log)
 382			pci_info(dev, "  bridge window %pR\n", res);
 383	}
 384}
 385
 386static void pci_read_bridge_mmio(struct pci_dev *dev, struct resource *res,
 387				 bool log)
 388{
 
 389	u16 mem_base_lo, mem_limit_lo;
 390	unsigned long base, limit;
 391	struct pci_bus_region region;
 
 392
 
 393	pci_read_config_word(dev, PCI_MEMORY_BASE, &mem_base_lo);
 394	pci_read_config_word(dev, PCI_MEMORY_LIMIT, &mem_limit_lo);
 395	base = ((unsigned long) mem_base_lo & PCI_MEMORY_RANGE_MASK) << 16;
 396	limit = ((unsigned long) mem_limit_lo & PCI_MEMORY_RANGE_MASK) << 16;
 397	if (base <= limit) {
 398		res->flags = (mem_base_lo & PCI_MEMORY_RANGE_TYPE_MASK) | IORESOURCE_MEM;
 399		region.start = base;
 400		region.end = limit + 0xfffff;
 401		pcibios_bus_to_resource(dev->bus, res, &region);
 402		if (log)
 403			pci_info(dev, "  bridge window %pR\n", res);
 404	}
 405}
 406
 407static void pci_read_bridge_mmio_pref(struct pci_dev *dev, struct resource *res,
 408				      bool log)
 409{
 
 410	u16 mem_base_lo, mem_limit_lo;
 411	u64 base64, limit64;
 412	pci_bus_addr_t base, limit;
 413	struct pci_bus_region region;
 
 414
 
 415	pci_read_config_word(dev, PCI_PREF_MEMORY_BASE, &mem_base_lo);
 416	pci_read_config_word(dev, PCI_PREF_MEMORY_LIMIT, &mem_limit_lo);
 417	base64 = (mem_base_lo & PCI_PREF_RANGE_MASK) << 16;
 418	limit64 = (mem_limit_lo & PCI_PREF_RANGE_MASK) << 16;
 419
 420	if ((mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) == PCI_PREF_RANGE_TYPE_64) {
 421		u32 mem_base_hi, mem_limit_hi;
 422
 423		pci_read_config_dword(dev, PCI_PREF_BASE_UPPER32, &mem_base_hi);
 424		pci_read_config_dword(dev, PCI_PREF_LIMIT_UPPER32, &mem_limit_hi);
 425
 426		/*
 427		 * Some bridges set the base > limit by default, and some
 428		 * (broken) BIOSes do not initialize them.  If we find
 429		 * this, just assume they are not being used.
 430		 */
 431		if (mem_base_hi <= mem_limit_hi) {
 432			base64 |= (u64) mem_base_hi << 32;
 433			limit64 |= (u64) mem_limit_hi << 32;
 
 
 
 
 
 
 
 
 434		}
 435	}
 436
 437	base = (pci_bus_addr_t) base64;
 438	limit = (pci_bus_addr_t) limit64;
 439
 440	if (base != base64) {
 441		pci_err(dev, "can't handle bridge window above 4GB (bus address %#010llx)\n",
 442			(unsigned long long) base64);
 443		return;
 444	}
 445
 446	if (base <= limit) {
 447		res->flags = (mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) |
 448					 IORESOURCE_MEM | IORESOURCE_PREFETCH;
 449		if (res->flags & PCI_PREF_RANGE_TYPE_64)
 450			res->flags |= IORESOURCE_MEM_64;
 451		region.start = base;
 452		region.end = limit + 0xfffff;
 453		pcibios_bus_to_resource(dev->bus, res, &region);
 454		if (log)
 455			pci_info(dev, "  bridge window %pR\n", res);
 456	}
 457}
 458
 459static void pci_read_bridge_windows(struct pci_dev *bridge)
 460{
 461	u32 buses;
 462	u16 io;
 463	u32 pmem, tmp;
 464	struct resource res;
 465
 466	pci_read_config_dword(bridge, PCI_PRIMARY_BUS, &buses);
 467	res.flags = IORESOURCE_BUS;
 468	res.start = (buses >> 8) & 0xff;
 469	res.end = (buses >> 16) & 0xff;
 470	pci_info(bridge, "PCI bridge to %pR%s\n", &res,
 471		 bridge->transparent ? " (subtractive decode)" : "");
 472
 473	pci_read_config_word(bridge, PCI_IO_BASE, &io);
 474	if (!io) {
 475		pci_write_config_word(bridge, PCI_IO_BASE, 0xe0f0);
 476		pci_read_config_word(bridge, PCI_IO_BASE, &io);
 477		pci_write_config_word(bridge, PCI_IO_BASE, 0x0);
 478	}
 479	if (io) {
 480		bridge->io_window = 1;
 481		pci_read_bridge_io(bridge, &res, true);
 482	}
 483
 484	pci_read_bridge_mmio(bridge, &res, true);
 485
 486	/*
 487	 * DECchip 21050 pass 2 errata: the bridge may miss an address
 488	 * disconnect boundary by one PCI data phase.  Workaround: do not
 489	 * use prefetching on this device.
 490	 */
 491	if (bridge->vendor == PCI_VENDOR_ID_DEC && bridge->device == 0x0001)
 492		return;
 493
 494	pci_read_config_dword(bridge, PCI_PREF_MEMORY_BASE, &pmem);
 495	if (!pmem) {
 496		pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE,
 497					       0xffe0fff0);
 498		pci_read_config_dword(bridge, PCI_PREF_MEMORY_BASE, &pmem);
 499		pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE, 0x0);
 500	}
 501	if (!pmem)
 502		return;
 503
 504	bridge->pref_window = 1;
 505
 506	if ((pmem & PCI_PREF_RANGE_TYPE_MASK) == PCI_PREF_RANGE_TYPE_64) {
 507
 508		/*
 509		 * Bridge claims to have a 64-bit prefetchable memory
 510		 * window; verify that the upper bits are actually
 511		 * writable.
 512		 */
 513		pci_read_config_dword(bridge, PCI_PREF_BASE_UPPER32, &pmem);
 514		pci_write_config_dword(bridge, PCI_PREF_BASE_UPPER32,
 515				       0xffffffff);
 516		pci_read_config_dword(bridge, PCI_PREF_BASE_UPPER32, &tmp);
 517		pci_write_config_dword(bridge, PCI_PREF_BASE_UPPER32, pmem);
 518		if (tmp)
 519			bridge->pref_64_window = 1;
 520	}
 521
 522	pci_read_bridge_mmio_pref(bridge, &res, true);
 523}
 524
 525void pci_read_bridge_bases(struct pci_bus *child)
 526{
 527	struct pci_dev *dev = child->self;
 528	struct resource *res;
 529	int i;
 530
 531	if (pci_is_root_bus(child))	/* It's a host bus, nothing to read */
 532		return;
 533
 534	pci_info(dev, "PCI bridge to %pR%s\n",
 535		 &child->busn_res,
 536		 dev->transparent ? " (subtractive decode)" : "");
 537
 538	pci_bus_remove_resources(child);
 539	for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++)
 540		child->resource[i] = &dev->resource[PCI_BRIDGE_RESOURCES+i];
 541
 542	pci_read_bridge_io(child->self, child->resource[0], false);
 543	pci_read_bridge_mmio(child->self, child->resource[1], false);
 544	pci_read_bridge_mmio_pref(child->self, child->resource[2], false);
 545
 546	if (dev->transparent) {
 547		pci_bus_for_each_resource(child->parent, res) {
 548			if (res && res->flags) {
 549				pci_bus_add_resource(child, res,
 550						     PCI_SUBTRACTIVE_DECODE);
 551				pci_info(dev, "  bridge window %pR (subtractive decode)\n",
 
 552					   res);
 553			}
 554		}
 555	}
 556}
 557
 558static struct pci_bus *pci_alloc_bus(struct pci_bus *parent)
 559{
 560	struct pci_bus *b;
 561
 562	b = kzalloc(sizeof(*b), GFP_KERNEL);
 563	if (!b)
 564		return NULL;
 565
 566	INIT_LIST_HEAD(&b->node);
 567	INIT_LIST_HEAD(&b->children);
 568	INIT_LIST_HEAD(&b->devices);
 569	INIT_LIST_HEAD(&b->slots);
 570	INIT_LIST_HEAD(&b->resources);
 571	b->max_bus_speed = PCI_SPEED_UNKNOWN;
 572	b->cur_bus_speed = PCI_SPEED_UNKNOWN;
 573#ifdef CONFIG_PCI_DOMAINS_GENERIC
 574	if (parent)
 575		b->domain_nr = parent->domain_nr;
 576#endif
 577	return b;
 578}
 579
 580static void pci_release_host_bridge_dev(struct device *dev)
 581{
 582	struct pci_host_bridge *bridge = to_pci_host_bridge(dev);
 583
 584	if (bridge->release_fn)
 585		bridge->release_fn(bridge);
 586
 587	pci_free_resource_list(&bridge->windows);
 588	pci_free_resource_list(&bridge->dma_ranges);
 589	kfree(bridge);
 590}
 591
 592static void pci_init_host_bridge(struct pci_host_bridge *bridge)
 593{
 594	INIT_LIST_HEAD(&bridge->windows);
 595	INIT_LIST_HEAD(&bridge->dma_ranges);
 596
 597	/*
 598	 * We assume we can manage these PCIe features.  Some systems may
 599	 * reserve these for use by the platform itself, e.g., an ACPI BIOS
 600	 * may implement its own AER handling and use _OSC to prevent the
 601	 * OS from interfering.
 602	 */
 603	bridge->native_aer = 1;
 604	bridge->native_pcie_hotplug = 1;
 605	bridge->native_shpc_hotplug = 1;
 606	bridge->native_pme = 1;
 607	bridge->native_ltr = 1;
 608	bridge->native_dpc = 1;
 609	bridge->domain_nr = PCI_DOMAIN_NR_NOT_SET;
 610	bridge->native_cxl_error = 1;
 611
 612	device_initialize(&bridge->dev);
 613}
 614
 615struct pci_host_bridge *pci_alloc_host_bridge(size_t priv)
 616{
 617	struct pci_host_bridge *bridge;
 618
 619	bridge = kzalloc(sizeof(*bridge) + priv, GFP_KERNEL);
 620	if (!bridge)
 621		return NULL;
 622
 623	pci_init_host_bridge(bridge);
 624	bridge->dev.release = pci_release_host_bridge_dev;
 625
 626	return bridge;
 627}
 628EXPORT_SYMBOL(pci_alloc_host_bridge);
 629
 630static void devm_pci_alloc_host_bridge_release(void *data)
 631{
 632	pci_free_host_bridge(data);
 633}
 634
 635struct pci_host_bridge *devm_pci_alloc_host_bridge(struct device *dev,
 636						   size_t priv)
 637{
 638	int ret;
 639	struct pci_host_bridge *bridge;
 640
 641	bridge = pci_alloc_host_bridge(priv);
 642	if (!bridge)
 643		return NULL;
 644
 645	bridge->dev.parent = dev;
 646
 647	ret = devm_add_action_or_reset(dev, devm_pci_alloc_host_bridge_release,
 648				       bridge);
 649	if (ret)
 650		return NULL;
 651
 652	ret = devm_of_pci_bridge_init(dev, bridge);
 653	if (ret)
 654		return NULL;
 655
 656	return bridge;
 657}
 658EXPORT_SYMBOL(devm_pci_alloc_host_bridge);
 659
 660void pci_free_host_bridge(struct pci_host_bridge *bridge)
 661{
 662	put_device(&bridge->dev);
 663}
 664EXPORT_SYMBOL(pci_free_host_bridge);
 665
 666/* Indexed by PCI_X_SSTATUS_FREQ (secondary bus mode and frequency) */
 667static const unsigned char pcix_bus_speed[] = {
 668	PCI_SPEED_UNKNOWN,		/* 0 */
 669	PCI_SPEED_66MHz_PCIX,		/* 1 */
 670	PCI_SPEED_100MHz_PCIX,		/* 2 */
 671	PCI_SPEED_133MHz_PCIX,		/* 3 */
 672	PCI_SPEED_UNKNOWN,		/* 4 */
 673	PCI_SPEED_66MHz_PCIX_ECC,	/* 5 */
 674	PCI_SPEED_100MHz_PCIX_ECC,	/* 6 */
 675	PCI_SPEED_133MHz_PCIX_ECC,	/* 7 */
 676	PCI_SPEED_UNKNOWN,		/* 8 */
 677	PCI_SPEED_66MHz_PCIX_266,	/* 9 */
 678	PCI_SPEED_100MHz_PCIX_266,	/* A */
 679	PCI_SPEED_133MHz_PCIX_266,	/* B */
 680	PCI_SPEED_UNKNOWN,		/* C */
 681	PCI_SPEED_66MHz_PCIX_533,	/* D */
 682	PCI_SPEED_100MHz_PCIX_533,	/* E */
 683	PCI_SPEED_133MHz_PCIX_533	/* F */
 684};
 685
 686/* Indexed by PCI_EXP_LNKCAP_SLS, PCI_EXP_LNKSTA_CLS */
 687const unsigned char pcie_link_speed[] = {
 688	PCI_SPEED_UNKNOWN,		/* 0 */
 689	PCIE_SPEED_2_5GT,		/* 1 */
 690	PCIE_SPEED_5_0GT,		/* 2 */
 691	PCIE_SPEED_8_0GT,		/* 3 */
 692	PCIE_SPEED_16_0GT,		/* 4 */
 693	PCIE_SPEED_32_0GT,		/* 5 */
 694	PCIE_SPEED_64_0GT,		/* 6 */
 695	PCI_SPEED_UNKNOWN,		/* 7 */
 696	PCI_SPEED_UNKNOWN,		/* 8 */
 697	PCI_SPEED_UNKNOWN,		/* 9 */
 698	PCI_SPEED_UNKNOWN,		/* A */
 699	PCI_SPEED_UNKNOWN,		/* B */
 700	PCI_SPEED_UNKNOWN,		/* C */
 701	PCI_SPEED_UNKNOWN,		/* D */
 702	PCI_SPEED_UNKNOWN,		/* E */
 703	PCI_SPEED_UNKNOWN		/* F */
 704};
 705EXPORT_SYMBOL_GPL(pcie_link_speed);
 706
 707const char *pci_speed_string(enum pci_bus_speed speed)
 708{
 709	/* Indexed by the pci_bus_speed enum */
 710	static const char *speed_strings[] = {
 711	    "33 MHz PCI",		/* 0x00 */
 712	    "66 MHz PCI",		/* 0x01 */
 713	    "66 MHz PCI-X",		/* 0x02 */
 714	    "100 MHz PCI-X",		/* 0x03 */
 715	    "133 MHz PCI-X",		/* 0x04 */
 716	    NULL,			/* 0x05 */
 717	    NULL,			/* 0x06 */
 718	    NULL,			/* 0x07 */
 719	    NULL,			/* 0x08 */
 720	    "66 MHz PCI-X 266",		/* 0x09 */
 721	    "100 MHz PCI-X 266",	/* 0x0a */
 722	    "133 MHz PCI-X 266",	/* 0x0b */
 723	    "Unknown AGP",		/* 0x0c */
 724	    "1x AGP",			/* 0x0d */
 725	    "2x AGP",			/* 0x0e */
 726	    "4x AGP",			/* 0x0f */
 727	    "8x AGP",			/* 0x10 */
 728	    "66 MHz PCI-X 533",		/* 0x11 */
 729	    "100 MHz PCI-X 533",	/* 0x12 */
 730	    "133 MHz PCI-X 533",	/* 0x13 */
 731	    "2.5 GT/s PCIe",		/* 0x14 */
 732	    "5.0 GT/s PCIe",		/* 0x15 */
 733	    "8.0 GT/s PCIe",		/* 0x16 */
 734	    "16.0 GT/s PCIe",		/* 0x17 */
 735	    "32.0 GT/s PCIe",		/* 0x18 */
 736	    "64.0 GT/s PCIe",		/* 0x19 */
 737	};
 738
 739	if (speed < ARRAY_SIZE(speed_strings))
 740		return speed_strings[speed];
 741	return "Unknown";
 742}
 743EXPORT_SYMBOL_GPL(pci_speed_string);
 744
 745void pcie_update_link_speed(struct pci_bus *bus, u16 linksta)
 746{
 747	bus->cur_bus_speed = pcie_link_speed[linksta & PCI_EXP_LNKSTA_CLS];
 748}
 749EXPORT_SYMBOL_GPL(pcie_update_link_speed);
 750
 751static unsigned char agp_speeds[] = {
 752	AGP_UNKNOWN,
 753	AGP_1X,
 754	AGP_2X,
 755	AGP_4X,
 756	AGP_8X
 757};
 758
 759static enum pci_bus_speed agp_speed(int agp3, int agpstat)
 760{
 761	int index = 0;
 762
 763	if (agpstat & 4)
 764		index = 3;
 765	else if (agpstat & 2)
 766		index = 2;
 767	else if (agpstat & 1)
 768		index = 1;
 769	else
 770		goto out;
 771
 772	if (agp3) {
 773		index += 2;
 774		if (index == 5)
 775			index = 0;
 776	}
 777
 778 out:
 779	return agp_speeds[index];
 780}
 781
 
 782static void pci_set_bus_speed(struct pci_bus *bus)
 783{
 784	struct pci_dev *bridge = bus->self;
 785	int pos;
 786
 787	pos = pci_find_capability(bridge, PCI_CAP_ID_AGP);
 788	if (!pos)
 789		pos = pci_find_capability(bridge, PCI_CAP_ID_AGP3);
 790	if (pos) {
 791		u32 agpstat, agpcmd;
 792
 793		pci_read_config_dword(bridge, pos + PCI_AGP_STATUS, &agpstat);
 794		bus->max_bus_speed = agp_speed(agpstat & 8, agpstat & 7);
 795
 796		pci_read_config_dword(bridge, pos + PCI_AGP_COMMAND, &agpcmd);
 797		bus->cur_bus_speed = agp_speed(agpstat & 8, agpcmd & 7);
 798	}
 799
 800	pos = pci_find_capability(bridge, PCI_CAP_ID_PCIX);
 801	if (pos) {
 802		u16 status;
 803		enum pci_bus_speed max;
 804
 805		pci_read_config_word(bridge, pos + PCI_X_BRIDGE_SSTATUS,
 806				     &status);
 807
 808		if (status & PCI_X_SSTATUS_533MHZ) {
 809			max = PCI_SPEED_133MHz_PCIX_533;
 810		} else if (status & PCI_X_SSTATUS_266MHZ) {
 811			max = PCI_SPEED_133MHz_PCIX_266;
 812		} else if (status & PCI_X_SSTATUS_133MHZ) {
 813			if ((status & PCI_X_SSTATUS_VERS) == PCI_X_SSTATUS_V2)
 814				max = PCI_SPEED_133MHz_PCIX_ECC;
 815			else
 816				max = PCI_SPEED_133MHz_PCIX;
 
 817		} else {
 818			max = PCI_SPEED_66MHz_PCIX;
 819		}
 820
 821		bus->max_bus_speed = max;
 822		bus->cur_bus_speed =
 823			pcix_bus_speed[FIELD_GET(PCI_X_SSTATUS_FREQ, status)];
 824
 825		return;
 826	}
 827
 828	if (pci_is_pcie(bridge)) {
 829		u32 linkcap;
 830		u16 linksta;
 831
 832		pcie_capability_read_dword(bridge, PCI_EXP_LNKCAP, &linkcap);
 833		bus->max_bus_speed = pcie_link_speed[linkcap & PCI_EXP_LNKCAP_SLS];
 834
 835		pcie_capability_read_word(bridge, PCI_EXP_LNKSTA, &linksta);
 836		pcie_update_link_speed(bus, linksta);
 837	}
 838}
 839
 840static struct irq_domain *pci_host_bridge_msi_domain(struct pci_bus *bus)
 841{
 842	struct irq_domain *d;
 843
 844	/* If the host bridge driver sets a MSI domain of the bridge, use it */
 845	d = dev_get_msi_domain(bus->bridge);
 846
 847	/*
 848	 * Any firmware interface that can resolve the msi_domain
 849	 * should be called from here.
 850	 */
 851	if (!d)
 852		d = pci_host_bridge_of_msi_domain(bus);
 853	if (!d)
 854		d = pci_host_bridge_acpi_msi_domain(bus);
 855
 856	/*
 857	 * If no IRQ domain was found via the OF tree, try looking it up
 858	 * directly through the fwnode_handle.
 859	 */
 860	if (!d) {
 861		struct fwnode_handle *fwnode = pci_root_bus_fwnode(bus);
 862
 863		if (fwnode)
 864			d = irq_find_matching_fwnode(fwnode,
 865						     DOMAIN_BUS_PCI_MSI);
 866	}
 867
 868	return d;
 869}
 870
 871static void pci_set_bus_msi_domain(struct pci_bus *bus)
 872{
 873	struct irq_domain *d;
 874	struct pci_bus *b;
 875
 876	/*
 877	 * The bus can be a root bus, a subordinate bus, or a virtual bus
 878	 * created by an SR-IOV device.  Walk up to the first bridge device
 879	 * found or derive the domain from the host bridge.
 880	 */
 881	for (b = bus, d = NULL; !d && !pci_is_root_bus(b); b = b->parent) {
 882		if (b->self)
 883			d = dev_get_msi_domain(&b->self->dev);
 884	}
 885
 886	if (!d)
 887		d = pci_host_bridge_msi_domain(b);
 888
 889	dev_set_msi_domain(&bus->dev, d);
 890}
 891
 892static int pci_register_host_bridge(struct pci_host_bridge *bridge)
 893{
 894	struct device *parent = bridge->dev.parent;
 895	struct resource_entry *window, *next, *n;
 896	struct pci_bus *bus, *b;
 897	resource_size_t offset, next_offset;
 898	LIST_HEAD(resources);
 899	struct resource *res, *next_res;
 900	char addr[64], *fmt;
 901	const char *name;
 902	int err;
 903
 904	bus = pci_alloc_bus(NULL);
 905	if (!bus)
 906		return -ENOMEM;
 907
 908	bridge->bus = bus;
 909
 910	bus->sysdata = bridge->sysdata;
 911	bus->ops = bridge->ops;
 912	bus->number = bus->busn_res.start = bridge->busnr;
 913#ifdef CONFIG_PCI_DOMAINS_GENERIC
 914	if (bridge->domain_nr == PCI_DOMAIN_NR_NOT_SET)
 915		bus->domain_nr = pci_bus_find_domain_nr(bus, parent);
 916	else
 917		bus->domain_nr = bridge->domain_nr;
 918	if (bus->domain_nr < 0) {
 919		err = bus->domain_nr;
 920		goto free;
 921	}
 922#endif
 923
 924	b = pci_find_bus(pci_domain_nr(bus), bridge->busnr);
 925	if (b) {
 926		/* Ignore it if we already got here via a different bridge */
 927		dev_dbg(&b->dev, "bus already known\n");
 928		err = -EEXIST;
 929		goto free;
 930	}
 931
 932	dev_set_name(&bridge->dev, "pci%04x:%02x", pci_domain_nr(bus),
 933		     bridge->busnr);
 934
 935	err = pcibios_root_bridge_prepare(bridge);
 936	if (err)
 937		goto free;
 938
 939	/* Temporarily move resources off the list */
 940	list_splice_init(&bridge->windows, &resources);
 941	err = device_add(&bridge->dev);
 942	if (err) {
 943		put_device(&bridge->dev);
 944		goto free;
 945	}
 946	bus->bridge = get_device(&bridge->dev);
 947	device_enable_async_suspend(bus->bridge);
 948	pci_set_bus_of_node(bus);
 949	pci_set_bus_msi_domain(bus);
 950	if (bridge->msi_domain && !dev_get_msi_domain(&bus->dev) &&
 951	    !pci_host_of_has_msi_map(parent))
 952		bus->bus_flags |= PCI_BUS_FLAGS_NO_MSI;
 953
 954	if (!parent)
 955		set_dev_node(bus->bridge, pcibus_to_node(bus));
 956
 957	bus->dev.class = &pcibus_class;
 958	bus->dev.parent = bus->bridge;
 959
 960	dev_set_name(&bus->dev, "%04x:%02x", pci_domain_nr(bus), bus->number);
 961	name = dev_name(&bus->dev);
 962
 963	err = device_register(&bus->dev);
 964	if (err)
 965		goto unregister;
 966
 967	pcibios_add_bus(bus);
 968
 969	if (bus->ops->add_bus) {
 970		err = bus->ops->add_bus(bus);
 971		if (WARN_ON(err < 0))
 972			dev_err(&bus->dev, "failed to add bus: %d\n", err);
 973	}
 974
 975	/* Create legacy_io and legacy_mem files for this bus */
 976	pci_create_legacy_files(bus);
 977
 978	if (parent)
 979		dev_info(parent, "PCI host bridge to bus %s\n", name);
 980	else
 981		pr_info("PCI host bridge to bus %s\n", name);
 982
 983	if (nr_node_ids > 1 && pcibus_to_node(bus) == NUMA_NO_NODE)
 984		dev_warn(&bus->dev, "Unknown NUMA node; performance will be reduced\n");
 985
 986	/* Coalesce contiguous windows */
 987	resource_list_for_each_entry_safe(window, n, &resources) {
 988		if (list_is_last(&window->node, &resources))
 989			break;
 990
 991		next = list_next_entry(window, node);
 992		offset = window->offset;
 993		res = window->res;
 994		next_offset = next->offset;
 995		next_res = next->res;
 996
 997		if (res->flags != next_res->flags || offset != next_offset)
 998			continue;
 999
1000		if (res->end + 1 == next_res->start) {
1001			next_res->start = res->start;
1002			res->flags = res->start = res->end = 0;
1003		}
1004	}
1005
1006	/* Add initial resources to the bus */
1007	resource_list_for_each_entry_safe(window, n, &resources) {
1008		offset = window->offset;
1009		res = window->res;
1010		if (!res->flags && !res->start && !res->end) {
1011			release_resource(res);
1012			resource_list_destroy_entry(window);
1013			continue;
1014		}
1015
1016		list_move_tail(&window->node, &bridge->windows);
1017
1018		if (res->flags & IORESOURCE_BUS)
1019			pci_bus_insert_busn_res(bus, bus->number, res->end);
1020		else
1021			pci_bus_add_resource(bus, res, 0);
1022
1023		if (offset) {
1024			if (resource_type(res) == IORESOURCE_IO)
1025				fmt = " (bus address [%#06llx-%#06llx])";
1026			else
1027				fmt = " (bus address [%#010llx-%#010llx])";
1028
1029			snprintf(addr, sizeof(addr), fmt,
1030				 (unsigned long long)(res->start - offset),
1031				 (unsigned long long)(res->end - offset));
1032		} else
1033			addr[0] = '\0';
1034
1035		dev_info(&bus->dev, "root bus resource %pR%s\n", res, addr);
1036	}
1037
1038	down_write(&pci_bus_sem);
1039	list_add_tail(&bus->node, &pci_root_buses);
1040	up_write(&pci_bus_sem);
1041
1042	return 0;
1043
1044unregister:
1045	put_device(&bridge->dev);
1046	device_del(&bridge->dev);
1047
1048free:
1049#ifdef CONFIG_PCI_DOMAINS_GENERIC
1050	pci_bus_release_domain_nr(bus, parent);
1051#endif
1052	kfree(bus);
1053	return err;
1054}
1055
1056static bool pci_bridge_child_ext_cfg_accessible(struct pci_dev *bridge)
1057{
1058	int pos;
1059	u32 status;
1060
1061	/*
1062	 * If extended config space isn't accessible on a bridge's primary
1063	 * bus, we certainly can't access it on the secondary bus.
1064	 */
1065	if (bridge->bus->bus_flags & PCI_BUS_FLAGS_NO_EXTCFG)
1066		return false;
1067
1068	/*
1069	 * PCIe Root Ports and switch ports are PCIe on both sides, so if
1070	 * extended config space is accessible on the primary, it's also
1071	 * accessible on the secondary.
1072	 */
1073	if (pci_is_pcie(bridge) &&
1074	    (pci_pcie_type(bridge) == PCI_EXP_TYPE_ROOT_PORT ||
1075	     pci_pcie_type(bridge) == PCI_EXP_TYPE_UPSTREAM ||
1076	     pci_pcie_type(bridge) == PCI_EXP_TYPE_DOWNSTREAM))
1077		return true;
1078
1079	/*
1080	 * For the other bridge types:
1081	 *   - PCI-to-PCI bridges
1082	 *   - PCIe-to-PCI/PCI-X forward bridges
1083	 *   - PCI/PCI-X-to-PCIe reverse bridges
1084	 * extended config space on the secondary side is only accessible
1085	 * if the bridge supports PCI-X Mode 2.
1086	 */
1087	pos = pci_find_capability(bridge, PCI_CAP_ID_PCIX);
1088	if (!pos)
1089		return false;
1090
1091	pci_read_config_dword(bridge, pos + PCI_X_STATUS, &status);
1092	return status & (PCI_X_STATUS_266MHZ | PCI_X_STATUS_533MHZ);
1093}
1094
1095static struct pci_bus *pci_alloc_child_bus(struct pci_bus *parent,
1096					   struct pci_dev *bridge, int busnr)
1097{
1098	struct pci_bus *child;
1099	struct pci_host_bridge *host;
1100	int i;
1101	int ret;
1102
1103	/* Allocate a new bus and inherit stuff from the parent */
1104	child = pci_alloc_bus(parent);
 
 
1105	if (!child)
1106		return NULL;
1107
1108	child->parent = parent;
 
 
1109	child->sysdata = parent->sysdata;
1110	child->bus_flags = parent->bus_flags;
1111
1112	host = pci_find_host_bridge(parent);
1113	if (host->child_ops)
1114		child->ops = host->child_ops;
1115	else
1116		child->ops = parent->ops;
1117
1118	/*
1119	 * Initialize some portions of the bus device, but don't register
1120	 * it now as the parent is not properly set up yet.
1121	 */
1122	child->dev.class = &pcibus_class;
1123	dev_set_name(&child->dev, "%04x:%02x", pci_domain_nr(child), busnr);
1124
1125	/* Set up the primary, secondary and subordinate bus numbers */
 
 
 
1126	child->number = child->busn_res.start = busnr;
1127	child->primary = parent->busn_res.start;
1128	child->busn_res.end = 0xff;
1129
1130	if (!bridge) {
1131		child->dev.parent = parent->bridge;
1132		goto add_dev;
1133	}
1134
1135	child->self = bridge;
1136	child->bridge = get_device(&bridge->dev);
1137	child->dev.parent = child->bridge;
1138	pci_set_bus_of_node(child);
1139	pci_set_bus_speed(child);
1140
1141	/*
1142	 * Check whether extended config space is accessible on the child
1143	 * bus.  Note that we currently assume it is always accessible on
1144	 * the root bus.
1145	 */
1146	if (!pci_bridge_child_ext_cfg_accessible(bridge)) {
1147		child->bus_flags |= PCI_BUS_FLAGS_NO_EXTCFG;
1148		pci_info(child, "extended config space not accessible\n");
1149	}
1150
1151	/* Set up default resource pointers and names */
1152	for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++) {
1153		child->resource[i] = &bridge->resource[PCI_BRIDGE_RESOURCES+i];
1154		child->resource[i]->name = child->name;
1155	}
1156	bridge->subordinate = child;
1157
1158add_dev:
1159	pci_set_bus_msi_domain(child);
1160	ret = device_register(&child->dev);
1161	WARN_ON(ret < 0);
1162
1163	pcibios_add_bus(child);
1164
1165	if (child->ops->add_bus) {
1166		ret = child->ops->add_bus(child);
1167		if (WARN_ON(ret < 0))
1168			dev_err(&child->dev, "failed to add bus: %d\n", ret);
1169	}
1170
1171	/* Create legacy_io and legacy_mem files for this bus */
1172	pci_create_legacy_files(child);
1173
1174	return child;
1175}
1176
1177struct pci_bus *pci_add_new_bus(struct pci_bus *parent, struct pci_dev *dev,
1178				int busnr)
1179{
1180	struct pci_bus *child;
1181
1182	child = pci_alloc_child_bus(parent, dev, busnr);
1183	if (child) {
1184		down_write(&pci_bus_sem);
1185		list_add_tail(&child->node, &parent->children);
1186		up_write(&pci_bus_sem);
1187	}
1188	return child;
1189}
1190EXPORT_SYMBOL(pci_add_new_bus);
1191
1192static void pci_enable_crs(struct pci_dev *pdev)
1193{
1194	u16 root_cap = 0;
1195
1196	/* Enable CRS Software Visibility if supported */
1197	pcie_capability_read_word(pdev, PCI_EXP_RTCAP, &root_cap);
1198	if (root_cap & PCI_EXP_RTCAP_CRSVIS)
1199		pcie_capability_set_word(pdev, PCI_EXP_RTCTL,
1200					 PCI_EXP_RTCTL_CRSSVE);
1201}
1202
1203static unsigned int pci_scan_child_bus_extend(struct pci_bus *bus,
1204					      unsigned int available_buses);
1205/**
1206 * pci_ea_fixed_busnrs() - Read fixed Secondary and Subordinate bus
1207 * numbers from EA capability.
1208 * @dev: Bridge
1209 * @sec: updated with secondary bus number from EA
1210 * @sub: updated with subordinate bus number from EA
1211 *
1212 * If @dev is a bridge with EA capability that specifies valid secondary
1213 * and subordinate bus numbers, return true with the bus numbers in @sec
1214 * and @sub.  Otherwise return false.
1215 */
1216static bool pci_ea_fixed_busnrs(struct pci_dev *dev, u8 *sec, u8 *sub)
1217{
1218	int ea, offset;
1219	u32 dw;
1220	u8 ea_sec, ea_sub;
1221
1222	if (dev->hdr_type != PCI_HEADER_TYPE_BRIDGE)
1223		return false;
1224
1225	/* find PCI EA capability in list */
1226	ea = pci_find_capability(dev, PCI_CAP_ID_EA);
1227	if (!ea)
1228		return false;
1229
1230	offset = ea + PCI_EA_FIRST_ENT;
1231	pci_read_config_dword(dev, offset, &dw);
1232	ea_sec = FIELD_GET(PCI_EA_SEC_BUS_MASK, dw);
1233	ea_sub = FIELD_GET(PCI_EA_SUB_BUS_MASK, dw);
1234	if (ea_sec  == 0 || ea_sub < ea_sec)
1235		return false;
1236
1237	*sec = ea_sec;
1238	*sub = ea_sub;
1239	return true;
1240}
1241
1242/*
1243 * pci_scan_bridge_extend() - Scan buses behind a bridge
1244 * @bus: Parent bus the bridge is on
1245 * @dev: Bridge itself
1246 * @max: Starting subordinate number of buses behind this bridge
1247 * @available_buses: Total number of buses available for this bridge and
1248 *		     the devices below. After the minimal bus space has
1249 *		     been allocated the remaining buses will be
1250 *		     distributed equally between hotplug-capable bridges.
1251 * @pass: Either %0 (scan already configured bridges) or %1 (scan bridges
1252 *        that need to be reconfigured.
1253 *
1254 * If it's a bridge, configure it and scan the bus behind it.
1255 * For CardBus bridges, we don't scan behind as the devices will
1256 * be handled by the bridge driver itself.
1257 *
1258 * We need to process bridges in two passes -- first we scan those
1259 * already configured by the BIOS and after we are done with all of
1260 * them, we proceed to assigning numbers to the remaining buses in
1261 * order to avoid overlaps between old and new bus numbers.
1262 *
1263 * Return: New subordinate number covering all buses behind this bridge.
1264 */
1265static int pci_scan_bridge_extend(struct pci_bus *bus, struct pci_dev *dev,
1266				  int max, unsigned int available_buses,
1267				  int pass)
1268{
1269	struct pci_bus *child;
1270	int is_cardbus = (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS);
1271	u32 buses, i, j = 0;
1272	u16 bctl;
1273	u8 primary, secondary, subordinate;
1274	int broken = 0;
1275	bool fixed_buses;
1276	u8 fixed_sec, fixed_sub;
1277	int next_busnr;
1278
1279	/*
1280	 * Make sure the bridge is powered on to be able to access config
1281	 * space of devices below it.
1282	 */
1283	pm_runtime_get_sync(&dev->dev);
1284
1285	pci_read_config_dword(dev, PCI_PRIMARY_BUS, &buses);
1286	primary = buses & 0xFF;
1287	secondary = (buses >> 8) & 0xFF;
1288	subordinate = (buses >> 16) & 0xFF;
1289
1290	pci_dbg(dev, "scanning [bus %02x-%02x] behind bridge, pass %d\n",
1291		secondary, subordinate, pass);
1292
1293	if (!primary && (primary != bus->number) && secondary && subordinate) {
1294		pci_warn(dev, "Primary bus is hard wired to 0\n");
1295		primary = bus->number;
1296	}
1297
1298	/* Check if setup is sensible at all */
1299	if (!pass &&
1300	    (primary != bus->number || secondary <= bus->number ||
1301	     secondary > subordinate)) {
1302		pci_info(dev, "bridge configuration invalid ([bus %02x-%02x]), reconfiguring\n",
1303			 secondary, subordinate);
1304		broken = 1;
1305	}
1306
1307	/*
1308	 * Disable Master-Abort Mode during probing to avoid reporting of
1309	 * bus errors in some architectures.
1310	 */
1311	pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &bctl);
1312	pci_write_config_word(dev, PCI_BRIDGE_CONTROL,
1313			      bctl & ~PCI_BRIDGE_CTL_MASTER_ABORT);
1314
1315	pci_enable_crs(dev);
1316
1317	if ((secondary || subordinate) && !pcibios_assign_all_busses() &&
1318	    !is_cardbus && !broken) {
1319		unsigned int cmax, buses;
1320
1321		/*
1322		 * Bus already configured by firmware, process it in the
1323		 * first pass and just note the configuration.
1324		 */
1325		if (pass)
1326			goto out;
1327
1328		/*
1329		 * The bus might already exist for two reasons: Either we
1330		 * are rescanning the bus or the bus is reachable through
1331		 * more than one bridge. The second case can happen with
1332		 * the i450NX chipset.
1333		 */
1334		child = pci_find_bus(pci_domain_nr(bus), secondary);
1335		if (!child) {
1336			child = pci_add_new_bus(bus, dev, secondary);
1337			if (!child)
1338				goto out;
1339			child->primary = primary;
1340			pci_bus_insert_busn_res(child, secondary, subordinate);
1341			child->bridge_ctl = bctl;
1342		}
1343
1344		buses = subordinate - secondary;
1345		cmax = pci_scan_child_bus_extend(child, buses);
1346		if (cmax > subordinate)
1347			pci_warn(dev, "bridge has subordinate %02x but max busn %02x\n",
1348				 subordinate, cmax);
1349
1350		/* Subordinate should equal child->busn_res.end */
1351		if (subordinate > max)
1352			max = subordinate;
1353	} else {
1354
1355		/*
1356		 * We need to assign a number to this bus which we always
1357		 * do in the second pass.
1358		 */
1359		if (!pass) {
1360			if (pcibios_assign_all_busses() || broken || is_cardbus)
1361
1362				/*
1363				 * Temporarily disable forwarding of the
1364				 * configuration cycles on all bridges in
1365				 * this bus segment to avoid possible
1366				 * conflicts in the second pass between two
1367				 * bridges programmed with overlapping bus
1368				 * ranges.
1369				 */
1370				pci_write_config_dword(dev, PCI_PRIMARY_BUS,
1371						       buses & ~0xffffff);
1372			goto out;
1373		}
1374
 
 
 
 
 
 
1375		/* Clear errors */
1376		pci_write_config_word(dev, PCI_STATUS, 0xffff);
1377
1378		/* Read bus numbers from EA Capability (if present) */
1379		fixed_buses = pci_ea_fixed_busnrs(dev, &fixed_sec, &fixed_sub);
1380		if (fixed_buses)
1381			next_busnr = fixed_sec;
1382		else
1383			next_busnr = max + 1;
1384
1385		/*
1386		 * Prevent assigning a bus number that already exists.
1387		 * This can happen when a bridge is hot-plugged, so in this
1388		 * case we only re-scan this bus.
1389		 */
1390		child = pci_find_bus(pci_domain_nr(bus), next_busnr);
1391		if (!child) {
1392			child = pci_add_new_bus(bus, dev, next_busnr);
1393			if (!child)
1394				goto out;
1395			pci_bus_insert_busn_res(child, next_busnr,
1396						bus->busn_res.end);
1397		}
1398		max++;
1399		if (available_buses)
1400			available_buses--;
1401
1402		buses = (buses & 0xff000000)
1403		      | ((unsigned int)(child->primary)     <<  0)
1404		      | ((unsigned int)(child->busn_res.start)   <<  8)
1405		      | ((unsigned int)(child->busn_res.end) << 16);
1406
1407		/*
1408		 * yenta.c forces a secondary latency timer of 176.
1409		 * Copy that behaviour here.
1410		 */
1411		if (is_cardbus) {
1412			buses &= ~0xff000000;
1413			buses |= CARDBUS_LATENCY_TIMER << 24;
1414		}
1415
1416		/* We need to blast all three values with a single write */
 
 
1417		pci_write_config_dword(dev, PCI_PRIMARY_BUS, buses);
1418
1419		if (!is_cardbus) {
1420			child->bridge_ctl = bctl;
1421			max = pci_scan_child_bus_extend(child, available_buses);
1422		} else {
1423
1424			/*
1425			 * For CardBus bridges, we leave 4 bus numbers as
1426			 * cards with a PCI-to-PCI bridge can be inserted
1427			 * later.
1428			 */
1429			for (i = 0; i < CARDBUS_RESERVE_BUSNR; i++) {
1430				struct pci_bus *parent = bus;
1431				if (pci_find_bus(pci_domain_nr(bus),
1432							max+i+1))
1433					break;
1434				while (parent->parent) {
1435					if ((!pcibios_assign_all_busses()) &&
1436					    (parent->busn_res.end > max) &&
1437					    (parent->busn_res.end <= max+i)) {
1438						j = 1;
1439					}
1440					parent = parent->parent;
1441				}
1442				if (j) {
1443
1444					/*
1445					 * Often, there are two CardBus
1446					 * bridges -- try to leave one
1447					 * valid bus number for each one.
1448					 */
1449					i /= 2;
1450					break;
1451				}
1452			}
1453			max += i;
1454		}
1455
1456		/*
1457		 * Set subordinate bus number to its real value.
1458		 * If fixed subordinate bus number exists from EA
1459		 * capability then use it.
1460		 */
1461		if (fixed_buses)
1462			max = fixed_sub;
 
 
 
1463		pci_bus_update_busn_res_end(child, max);
1464		pci_write_config_byte(dev, PCI_SUBORDINATE_BUS, max);
1465	}
1466
1467	sprintf(child->name,
1468		(is_cardbus ? "PCI CardBus %04x:%02x" : "PCI Bus %04x:%02x"),
1469		pci_domain_nr(bus), child->number);
1470
1471	/* Check that all devices are accessible */
1472	while (bus->parent) {
1473		if ((child->busn_res.end > bus->busn_res.end) ||
1474		    (child->number > bus->busn_res.end) ||
1475		    (child->number < bus->number) ||
1476		    (child->busn_res.end < bus->number)) {
1477			dev_info(&dev->dev, "devices behind bridge are unusable because %pR cannot be assigned for them\n",
1478				 &child->busn_res);
1479			break;
 
 
 
 
 
 
1480		}
1481		bus = bus->parent;
1482	}
1483
1484out:
1485	pci_write_config_word(dev, PCI_BRIDGE_CONTROL, bctl);
1486
1487	pm_runtime_put(&dev->dev);
1488
1489	return max;
1490}
1491
1492/*
1493 * pci_scan_bridge() - Scan buses behind a bridge
1494 * @bus: Parent bus the bridge is on
1495 * @dev: Bridge itself
1496 * @max: Starting subordinate number of buses behind this bridge
1497 * @pass: Either %0 (scan already configured bridges) or %1 (scan bridges
1498 *        that need to be reconfigured.
1499 *
1500 * If it's a bridge, configure it and scan the bus behind it.
1501 * For CardBus bridges, we don't scan behind as the devices will
1502 * be handled by the bridge driver itself.
1503 *
1504 * We need to process bridges in two passes -- first we scan those
1505 * already configured by the BIOS and after we are done with all of
1506 * them, we proceed to assigning numbers to the remaining buses in
1507 * order to avoid overlaps between old and new bus numbers.
1508 *
1509 * Return: New subordinate number covering all buses behind this bridge.
1510 */
1511int pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass)
1512{
1513	return pci_scan_bridge_extend(bus, dev, max, 0, pass);
1514}
1515EXPORT_SYMBOL(pci_scan_bridge);
1516
1517/*
1518 * Read interrupt line and base address registers.
1519 * The architecture-dependent code can tweak these, of course.
1520 */
1521static void pci_read_irq(struct pci_dev *dev)
1522{
1523	unsigned char irq;
1524
1525	/* VFs are not allowed to use INTx, so skip the config reads */
1526	if (dev->is_virtfn) {
1527		dev->pin = 0;
1528		dev->irq = 0;
1529		return;
1530	}
1531
1532	pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &irq);
1533	dev->pin = irq;
1534	if (irq)
1535		pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &irq);
1536	dev->irq = irq;
1537}
1538
1539void set_pcie_port_type(struct pci_dev *pdev)
1540{
1541	int pos;
1542	u16 reg16;
1543	u32 reg32;
1544	int type;
1545	struct pci_dev *parent;
1546
1547	pos = pci_find_capability(pdev, PCI_CAP_ID_EXP);
1548	if (!pos)
1549		return;
1550
1551	pdev->pcie_cap = pos;
1552	pci_read_config_word(pdev, pos + PCI_EXP_FLAGS, &reg16);
1553	pdev->pcie_flags_reg = reg16;
1554	pci_read_config_dword(pdev, pos + PCI_EXP_DEVCAP, &pdev->devcap);
1555	pdev->pcie_mpss = FIELD_GET(PCI_EXP_DEVCAP_PAYLOAD, pdev->devcap);
1556
1557	pcie_capability_read_dword(pdev, PCI_EXP_LNKCAP, &reg32);
1558	if (reg32 & PCI_EXP_LNKCAP_DLLLARC)
1559		pdev->link_active_reporting = 1;
1560
1561	parent = pci_upstream_bridge(pdev);
1562	if (!parent)
1563		return;
1564
1565	/*
1566	 * Some systems do not identify their upstream/downstream ports
1567	 * correctly so detect impossible configurations here and correct
1568	 * the port type accordingly.
1569	 */
1570	type = pci_pcie_type(pdev);
1571	if (type == PCI_EXP_TYPE_DOWNSTREAM) {
1572		/*
1573		 * If pdev claims to be downstream port but the parent
1574		 * device is also downstream port assume pdev is actually
1575		 * upstream port.
1576		 */
1577		if (pcie_downstream_port(parent)) {
1578			pci_info(pdev, "claims to be downstream port but is acting as upstream port, correcting type\n");
1579			pdev->pcie_flags_reg &= ~PCI_EXP_FLAGS_TYPE;
1580			pdev->pcie_flags_reg |= PCI_EXP_TYPE_UPSTREAM;
1581		}
1582	} else if (type == PCI_EXP_TYPE_UPSTREAM) {
1583		/*
1584		 * If pdev claims to be upstream port but the parent
1585		 * device is also upstream port assume pdev is actually
1586		 * downstream port.
1587		 */
1588		if (pci_pcie_type(parent) == PCI_EXP_TYPE_UPSTREAM) {
1589			pci_info(pdev, "claims to be upstream port but is acting as downstream port, correcting type\n");
1590			pdev->pcie_flags_reg &= ~PCI_EXP_FLAGS_TYPE;
1591			pdev->pcie_flags_reg |= PCI_EXP_TYPE_DOWNSTREAM;
1592		}
1593	}
1594}
1595
1596void set_pcie_hotplug_bridge(struct pci_dev *pdev)
1597{
1598	u32 reg32;
1599
1600	pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP, &reg32);
1601	if (reg32 & PCI_EXP_SLTCAP_HPC)
1602		pdev->is_hotplug_bridge = 1;
1603}
1604
1605static void set_pcie_thunderbolt(struct pci_dev *dev)
1606{
1607	u16 vsec;
1608
1609	/* Is the device part of a Thunderbolt controller? */
1610	vsec = pci_find_vsec_capability(dev, PCI_VENDOR_ID_INTEL, PCI_VSEC_ID_INTEL_TBT);
1611	if (vsec)
1612		dev->is_thunderbolt = 1;
1613}
1614
1615static void set_pcie_untrusted(struct pci_dev *dev)
1616{
1617	struct pci_dev *parent;
1618
1619	/*
1620	 * If the upstream bridge is untrusted we treat this device
1621	 * untrusted as well.
1622	 */
1623	parent = pci_upstream_bridge(dev);
1624	if (parent && (parent->untrusted || parent->external_facing))
1625		dev->untrusted = true;
1626}
1627
1628static void pci_set_removable(struct pci_dev *dev)
1629{
1630	struct pci_dev *parent = pci_upstream_bridge(dev);
1631
1632	/*
1633	 * We (only) consider everything downstream from an external_facing
1634	 * device to be removable by the user. We're mainly concerned with
1635	 * consumer platforms with user accessible thunderbolt ports that are
1636	 * vulnerable to DMA attacks, and we expect those ports to be marked by
1637	 * the firmware as external_facing. Devices in traditional hotplug
1638	 * slots can technically be removed, but the expectation is that unless
1639	 * the port is marked with external_facing, such devices are less
1640	 * accessible to user / may not be removed by end user, and thus not
1641	 * exposed as "removable" to userspace.
1642	 */
1643	if (parent &&
1644	    (parent->external_facing || dev_is_removable(&parent->dev)))
1645		dev_set_removable(&dev->dev, DEVICE_REMOVABLE);
1646}
1647
1648/**
1649 * pci_ext_cfg_is_aliased - Is ext config space just an alias of std config?
1650 * @dev: PCI device
1651 *
1652 * PCI Express to PCI/PCI-X Bridge Specification, rev 1.0, 4.1.4 says that
1653 * when forwarding a type1 configuration request the bridge must check that
1654 * the extended register address field is zero.  The bridge is not permitted
1655 * to forward the transactions and must handle it as an Unsupported Request.
1656 * Some bridges do not follow this rule and simply drop the extended register
1657 * bits, resulting in the standard config space being aliased, every 256
1658 * bytes across the entire configuration space.  Test for this condition by
1659 * comparing the first dword of each potential alias to the vendor/device ID.
1660 * Known offenders:
1661 *   ASM1083/1085 PCIe-to-PCI Reversible Bridge (1b21:1080, rev 01 & 03)
1662 *   AMD/ATI SBx00 PCI to PCI Bridge (1002:4384, rev 40)
1663 */
1664static bool pci_ext_cfg_is_aliased(struct pci_dev *dev)
1665{
1666#ifdef CONFIG_PCI_QUIRKS
1667	int pos, ret;
1668	u32 header, tmp;
1669
1670	pci_read_config_dword(dev, PCI_VENDOR_ID, &header);
1671
1672	for (pos = PCI_CFG_SPACE_SIZE;
1673	     pos < PCI_CFG_SPACE_EXP_SIZE; pos += PCI_CFG_SPACE_SIZE) {
1674		ret = pci_read_config_dword(dev, pos, &tmp);
1675		if ((ret != PCIBIOS_SUCCESSFUL) || (header != tmp))
1676			return false;
1677	}
1678
1679	return true;
1680#else
1681	return false;
1682#endif
1683}
1684
1685/**
1686 * pci_cfg_space_size_ext - Get the configuration space size of the PCI device
1687 * @dev: PCI device
1688 *
1689 * Regular PCI devices have 256 bytes, but PCI-X 2 and PCI Express devices
1690 * have 4096 bytes.  Even if the device is capable, that doesn't mean we can
1691 * access it.  Maybe we don't have a way to generate extended config space
1692 * accesses, or the device is behind a reverse Express bridge.  So we try
1693 * reading the dword at 0x100 which must either be 0 or a valid extended
1694 * capability header.
1695 */
1696static int pci_cfg_space_size_ext(struct pci_dev *dev)
1697{
1698	u32 status;
1699	int pos = PCI_CFG_SPACE_SIZE;
1700
1701	if (pci_read_config_dword(dev, pos, &status) != PCIBIOS_SUCCESSFUL)
1702		return PCI_CFG_SPACE_SIZE;
1703	if (PCI_POSSIBLE_ERROR(status) || pci_ext_cfg_is_aliased(dev))
1704		return PCI_CFG_SPACE_SIZE;
1705
1706	return PCI_CFG_SPACE_EXP_SIZE;
 
 
 
1707}
1708
1709int pci_cfg_space_size(struct pci_dev *dev)
1710{
1711	int pos;
1712	u32 status;
1713	u16 class;
1714
1715#ifdef CONFIG_PCI_IOV
1716	/*
1717	 * Per the SR-IOV specification (rev 1.1, sec 3.5), VFs are required to
1718	 * implement a PCIe capability and therefore must implement extended
1719	 * config space.  We can skip the NO_EXTCFG test below and the
1720	 * reachability/aliasing test in pci_cfg_space_size_ext() by virtue of
1721	 * the fact that the SR-IOV capability on the PF resides in extended
1722	 * config space and must be accessible and non-aliased to have enabled
1723	 * support for this VF.  This is a micro performance optimization for
1724	 * systems supporting many VFs.
1725	 */
1726	if (dev->is_virtfn)
1727		return PCI_CFG_SPACE_EXP_SIZE;
1728#endif
1729
1730	if (dev->bus->bus_flags & PCI_BUS_FLAGS_NO_EXTCFG)
1731		return PCI_CFG_SPACE_SIZE;
1732
1733	class = dev->class >> 8;
1734	if (class == PCI_CLASS_BRIDGE_HOST)
1735		return pci_cfg_space_size_ext(dev);
1736
1737	if (pci_is_pcie(dev))
1738		return pci_cfg_space_size_ext(dev);
1739
1740	pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1741	if (!pos)
1742		return PCI_CFG_SPACE_SIZE;
1743
1744	pci_read_config_dword(dev, pos + PCI_X_STATUS, &status);
1745	if (status & (PCI_X_STATUS_266MHZ | PCI_X_STATUS_533MHZ))
1746		return pci_cfg_space_size_ext(dev);
1747
1748	return PCI_CFG_SPACE_SIZE;
1749}
1750
1751static u32 pci_class(struct pci_dev *dev)
1752{
1753	u32 class;
1754
1755#ifdef CONFIG_PCI_IOV
1756	if (dev->is_virtfn)
1757		return dev->physfn->sriov->class;
1758#endif
1759	pci_read_config_dword(dev, PCI_CLASS_REVISION, &class);
1760	return class;
1761}
1762
1763static void pci_subsystem_ids(struct pci_dev *dev, u16 *vendor, u16 *device)
1764{
1765#ifdef CONFIG_PCI_IOV
1766	if (dev->is_virtfn) {
1767		*vendor = dev->physfn->sriov->subsystem_vendor;
1768		*device = dev->physfn->sriov->subsystem_device;
1769		return;
1770	}
1771#endif
1772	pci_read_config_word(dev, PCI_SUBSYSTEM_VENDOR_ID, vendor);
1773	pci_read_config_word(dev, PCI_SUBSYSTEM_ID, device);
1774}
1775
1776static u8 pci_hdr_type(struct pci_dev *dev)
1777{
1778	u8 hdr_type;
1779
1780#ifdef CONFIG_PCI_IOV
1781	if (dev->is_virtfn)
1782		return dev->physfn->sriov->hdr_type;
1783#endif
1784	pci_read_config_byte(dev, PCI_HEADER_TYPE, &hdr_type);
1785	return hdr_type;
1786}
1787
1788#define LEGACY_IO_RESOURCE	(IORESOURCE_IO | IORESOURCE_PCI_FIXED)
1789
1790/**
1791 * pci_intx_mask_broken - Test PCI_COMMAND_INTX_DISABLE writability
1792 * @dev: PCI device
1793 *
1794 * Test whether PCI_COMMAND_INTX_DISABLE is writable for @dev.  Check this
1795 * at enumeration-time to avoid modifying PCI_COMMAND at run-time.
1796 */
1797static int pci_intx_mask_broken(struct pci_dev *dev)
1798{
1799	u16 orig, toggle, new;
1800
1801	pci_read_config_word(dev, PCI_COMMAND, &orig);
1802	toggle = orig ^ PCI_COMMAND_INTX_DISABLE;
1803	pci_write_config_word(dev, PCI_COMMAND, toggle);
1804	pci_read_config_word(dev, PCI_COMMAND, &new);
1805
1806	pci_write_config_word(dev, PCI_COMMAND, orig);
1807
1808	/*
1809	 * PCI_COMMAND_INTX_DISABLE was reserved and read-only prior to PCI
1810	 * r2.3, so strictly speaking, a device is not *broken* if it's not
1811	 * writable.  But we'll live with the misnomer for now.
1812	 */
1813	if (new != toggle)
1814		return 1;
1815	return 0;
1816}
1817
1818static void early_dump_pci_device(struct pci_dev *pdev)
1819{
1820	u32 value[256 / 4];
1821	int i;
1822
1823	pci_info(pdev, "config space:\n");
1824
1825	for (i = 0; i < 256; i += 4)
1826		pci_read_config_dword(pdev, i, &value[i / 4]);
1827
1828	print_hex_dump(KERN_INFO, "", DUMP_PREFIX_OFFSET, 16, 1,
1829		       value, 256, false);
1830}
1831
1832static const char *pci_type_str(struct pci_dev *dev)
1833{
1834	static const char * const str[] = {
1835		"PCIe Endpoint",
1836		"PCIe Legacy Endpoint",
1837		"PCIe unknown",
1838		"PCIe unknown",
1839		"PCIe Root Port",
1840		"PCIe Switch Upstream Port",
1841		"PCIe Switch Downstream Port",
1842		"PCIe to PCI/PCI-X bridge",
1843		"PCI/PCI-X to PCIe bridge",
1844		"PCIe Root Complex Integrated Endpoint",
1845		"PCIe Root Complex Event Collector",
1846	};
1847	int type;
1848
1849	if (pci_is_pcie(dev)) {
1850		type = pci_pcie_type(dev);
1851		if (type < ARRAY_SIZE(str))
1852			return str[type];
1853
1854		return "PCIe unknown";
1855	}
1856
1857	switch (dev->hdr_type) {
1858	case PCI_HEADER_TYPE_NORMAL:
1859		return "conventional PCI endpoint";
1860	case PCI_HEADER_TYPE_BRIDGE:
1861		return "conventional PCI bridge";
1862	case PCI_HEADER_TYPE_CARDBUS:
1863		return "CardBus bridge";
1864	default:
1865		return "conventional PCI";
1866	}
1867}
1868
1869/**
1870 * pci_setup_device - Fill in class and map information of a device
1871 * @dev: the device structure to fill
1872 *
1873 * Initialize the device structure with information about the device's
1874 * vendor,class,memory and IO-space addresses, IRQ lines etc.
1875 * Called at initialisation of the PCI subsystem and by CardBus services.
1876 * Returns 0 on success and negative if unknown type of device (not normal,
1877 * bridge or CardBus).
1878 */
1879int pci_setup_device(struct pci_dev *dev)
1880{
1881	u32 class;
1882	u16 cmd;
1883	u8 hdr_type;
1884	int err, pos = 0;
 
1885	struct pci_bus_region region;
1886	struct resource *res;
1887
1888	hdr_type = pci_hdr_type(dev);
 
1889
1890	dev->sysdata = dev->bus->sysdata;
1891	dev->dev.parent = dev->bus->bridge;
1892	dev->dev.bus = &pci_bus_type;
1893	dev->hdr_type = hdr_type & 0x7f;
1894	dev->multifunction = !!(hdr_type & 0x80);
1895	dev->error_state = pci_channel_io_normal;
1896	set_pcie_port_type(dev);
1897
1898	err = pci_set_of_node(dev);
1899	if (err)
1900		return err;
1901	pci_set_acpi_fwnode(dev);
1902
1903	pci_dev_assign_slot(dev);
1904
1905	/*
1906	 * Assume 32-bit PCI; let 64-bit PCI cards (which are far rarer)
1907	 * set this higher, assuming the system even supports it.
1908	 */
1909	dev->dma_mask = 0xffffffff;
1910
1911	dev_set_name(&dev->dev, "%04x:%02x:%02x.%d", pci_domain_nr(dev->bus),
1912		     dev->bus->number, PCI_SLOT(dev->devfn),
1913		     PCI_FUNC(dev->devfn));
1914
1915	class = pci_class(dev);
1916
1917	dev->revision = class & 0xff;
1918	dev->class = class >> 8;		    /* upper 3 bytes */
1919
1920	if (pci_early_dump)
1921		early_dump_pci_device(dev);
1922
1923	/* Need to have dev->class ready */
1924	dev->cfg_size = pci_cfg_space_size(dev);
1925
1926	/* Need to have dev->cfg_size ready */
1927	set_pcie_thunderbolt(dev);
1928
1929	set_pcie_untrusted(dev);
1930
1931	/* "Unknown power state" */
1932	dev->current_state = PCI_UNKNOWN;
1933
1934	/* Early fixups, before probing the BARs */
1935	pci_fixup_device(pci_fixup_early, dev);
1936
1937	pci_set_removable(dev);
1938
1939	pci_info(dev, "[%04x:%04x] type %02x class %#08x %s\n",
1940		 dev->vendor, dev->device, dev->hdr_type, dev->class,
1941		 pci_type_str(dev));
1942
1943	/* Device class may be changed after fixup */
1944	class = dev->class >> 8;
1945
1946	if (dev->non_compliant_bars && !dev->mmio_always_on) {
1947		pci_read_config_word(dev, PCI_COMMAND, &cmd);
1948		if (cmd & (PCI_COMMAND_IO | PCI_COMMAND_MEMORY)) {
1949			pci_info(dev, "device has non-compliant BARs; disabling IO/MEM decoding\n");
1950			cmd &= ~PCI_COMMAND_IO;
1951			cmd &= ~PCI_COMMAND_MEMORY;
1952			pci_write_config_word(dev, PCI_COMMAND, cmd);
1953		}
1954	}
1955
1956	dev->broken_intx_masking = pci_intx_mask_broken(dev);
1957
1958	switch (dev->hdr_type) {		    /* header type */
1959	case PCI_HEADER_TYPE_NORMAL:		    /* standard header */
1960		if (class == PCI_CLASS_BRIDGE_PCI)
1961			goto bad;
1962		pci_read_irq(dev);
1963		pci_read_bases(dev, 6, PCI_ROM_ADDRESS);
1964
1965		pci_subsystem_ids(dev, &dev->subsystem_vendor, &dev->subsystem_device);
1966
1967		/*
1968		 * Do the ugly legacy mode stuff here rather than broken chip
1969		 * quirk code. Legacy mode ATA controllers have fixed
1970		 * addresses. These are not always echoed in BAR0-3, and
1971		 * BAR0-3 in a few cases contain junk!
1972		 */
1973		if (class == PCI_CLASS_STORAGE_IDE) {
1974			u8 progif;
1975			pci_read_config_byte(dev, PCI_CLASS_PROG, &progif);
1976			if ((progif & 1) == 0) {
1977				region.start = 0x1F0;
1978				region.end = 0x1F7;
1979				res = &dev->resource[0];
1980				res->flags = LEGACY_IO_RESOURCE;
1981				pcibios_bus_to_resource(dev->bus, res, &region);
1982				pci_info(dev, "BAR 0 %pR: legacy IDE quirk\n",
1983					 res);
1984				region.start = 0x3F6;
1985				region.end = 0x3F6;
1986				res = &dev->resource[1];
1987				res->flags = LEGACY_IO_RESOURCE;
1988				pcibios_bus_to_resource(dev->bus, res, &region);
1989				pci_info(dev, "BAR 1 %pR: legacy IDE quirk\n",
1990					 res);
1991			}
1992			if ((progif & 4) == 0) {
1993				region.start = 0x170;
1994				region.end = 0x177;
1995				res = &dev->resource[2];
1996				res->flags = LEGACY_IO_RESOURCE;
1997				pcibios_bus_to_resource(dev->bus, res, &region);
1998				pci_info(dev, "BAR 2 %pR: legacy IDE quirk\n",
1999					 res);
2000				region.start = 0x376;
2001				region.end = 0x376;
2002				res = &dev->resource[3];
2003				res->flags = LEGACY_IO_RESOURCE;
2004				pcibios_bus_to_resource(dev->bus, res, &region);
2005				pci_info(dev, "BAR 3 %pR: legacy IDE quirk\n",
2006					 res);
2007			}
2008		}
2009		break;
2010
2011	case PCI_HEADER_TYPE_BRIDGE:		    /* bridge header */
2012		/*
2013		 * The PCI-to-PCI bridge spec requires that subtractive
2014		 * decoding (i.e. transparent) bridge must have programming
2015		 * interface code of 0x01.
2016		 */
2017		pci_read_irq(dev);
2018		dev->transparent = ((dev->class & 0xff) == 1);
2019		pci_read_bases(dev, 2, PCI_ROM_ADDRESS1);
2020		pci_read_bridge_windows(dev);
2021		set_pcie_hotplug_bridge(dev);
2022		pos = pci_find_capability(dev, PCI_CAP_ID_SSVID);
2023		if (pos) {
2024			pci_read_config_word(dev, pos + PCI_SSVID_VENDOR_ID, &dev->subsystem_vendor);
2025			pci_read_config_word(dev, pos + PCI_SSVID_DEVICE_ID, &dev->subsystem_device);
2026		}
2027		break;
2028
2029	case PCI_HEADER_TYPE_CARDBUS:		    /* CardBus bridge header */
2030		if (class != PCI_CLASS_BRIDGE_CARDBUS)
2031			goto bad;
2032		pci_read_irq(dev);
2033		pci_read_bases(dev, 1, 0);
2034		pci_read_config_word(dev, PCI_CB_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor);
2035		pci_read_config_word(dev, PCI_CB_SUBSYSTEM_ID, &dev->subsystem_device);
2036		break;
2037
2038	default:				    /* unknown header */
2039		pci_err(dev, "unknown header type %02x, ignoring device\n",
2040			dev->hdr_type);
2041		pci_release_of_node(dev);
2042		return -EIO;
2043
2044	bad:
2045		pci_err(dev, "ignoring class %#08x (doesn't match header type %02x)\n",
2046			dev->class, dev->hdr_type);
2047		dev->class = PCI_CLASS_NOT_DEFINED << 8;
2048	}
2049
2050	/* We found a fine healthy device, go go go... */
2051	return 0;
2052}
2053
2054static void pci_configure_mps(struct pci_dev *dev)
2055{
2056	struct pci_dev *bridge = pci_upstream_bridge(dev);
2057	int mps, mpss, p_mps, rc;
2058
2059	if (!pci_is_pcie(dev))
2060		return;
2061
2062	/* MPS and MRRS fields are of type 'RsvdP' for VFs, short-circuit out */
2063	if (dev->is_virtfn)
2064		return;
2065
2066	/*
2067	 * For Root Complex Integrated Endpoints, program the maximum
2068	 * supported value unless limited by the PCIE_BUS_PEER2PEER case.
2069	 */
2070	if (pci_pcie_type(dev) == PCI_EXP_TYPE_RC_END) {
2071		if (pcie_bus_config == PCIE_BUS_PEER2PEER)
2072			mps = 128;
2073		else
2074			mps = 128 << dev->pcie_mpss;
2075		rc = pcie_set_mps(dev, mps);
2076		if (rc) {
2077			pci_warn(dev, "can't set Max Payload Size to %d; if necessary, use \"pci=pcie_bus_safe\" and report a bug\n",
2078				 mps);
2079		}
2080		return;
2081	}
2082
2083	if (!bridge || !pci_is_pcie(bridge))
2084		return;
2085
2086	mps = pcie_get_mps(dev);
2087	p_mps = pcie_get_mps(bridge);
2088
2089	if (mps == p_mps)
2090		return;
2091
2092	if (pcie_bus_config == PCIE_BUS_TUNE_OFF) {
2093		pci_warn(dev, "Max Payload Size %d, but upstream %s set to %d; if necessary, use \"pci=pcie_bus_safe\" and report a bug\n",
2094			 mps, pci_name(bridge), p_mps);
2095		return;
2096	}
2097
2098	/*
2099	 * Fancier MPS configuration is done later by
2100	 * pcie_bus_configure_settings()
2101	 */
2102	if (pcie_bus_config != PCIE_BUS_DEFAULT)
2103		return;
2104
2105	mpss = 128 << dev->pcie_mpss;
2106	if (mpss < p_mps && pci_pcie_type(bridge) == PCI_EXP_TYPE_ROOT_PORT) {
2107		pcie_set_mps(bridge, mpss);
2108		pci_info(dev, "Upstream bridge's Max Payload Size set to %d (was %d, max %d)\n",
2109			 mpss, p_mps, 128 << bridge->pcie_mpss);
2110		p_mps = pcie_get_mps(bridge);
2111	}
2112
2113	rc = pcie_set_mps(dev, p_mps);
2114	if (rc) {
2115		pci_warn(dev, "can't set Max Payload Size to %d; if necessary, use \"pci=pcie_bus_safe\" and report a bug\n",
2116			 p_mps);
2117		return;
2118	}
2119
2120	pci_info(dev, "Max Payload Size set to %d (was %d, max %d)\n",
2121		 p_mps, mps, mpss);
2122}
2123
2124int pci_configure_extended_tags(struct pci_dev *dev, void *ign)
2125{
2126	struct pci_host_bridge *host;
2127	u32 cap;
2128	u16 ctl;
2129	int ret;
2130
2131	if (!pci_is_pcie(dev))
2132		return 0;
2133
2134	ret = pcie_capability_read_dword(dev, PCI_EXP_DEVCAP, &cap);
2135	if (ret)
2136		return 0;
2137
2138	if (!(cap & PCI_EXP_DEVCAP_EXT_TAG))
2139		return 0;
2140
2141	ret = pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &ctl);
2142	if (ret)
2143		return 0;
2144
2145	host = pci_find_host_bridge(dev->bus);
2146	if (!host)
2147		return 0;
2148
2149	/*
2150	 * If some device in the hierarchy doesn't handle Extended Tags
2151	 * correctly, make sure they're disabled.
2152	 */
2153	if (host->no_ext_tags) {
2154		if (ctl & PCI_EXP_DEVCTL_EXT_TAG) {
2155			pci_info(dev, "disabling Extended Tags\n");
2156			pcie_capability_clear_word(dev, PCI_EXP_DEVCTL,
2157						   PCI_EXP_DEVCTL_EXT_TAG);
2158		}
2159		return 0;
2160	}
2161
2162	if (!(ctl & PCI_EXP_DEVCTL_EXT_TAG)) {
2163		pci_info(dev, "enabling Extended Tags\n");
2164		pcie_capability_set_word(dev, PCI_EXP_DEVCTL,
2165					 PCI_EXP_DEVCTL_EXT_TAG);
2166	}
2167	return 0;
2168}
2169
2170/**
2171 * pcie_relaxed_ordering_enabled - Probe for PCIe relaxed ordering enable
2172 * @dev: PCI device to query
2173 *
2174 * Returns true if the device has enabled relaxed ordering attribute.
2175 */
2176bool pcie_relaxed_ordering_enabled(struct pci_dev *dev)
2177{
2178	u16 v;
2179
2180	pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &v);
2181
2182	return !!(v & PCI_EXP_DEVCTL_RELAX_EN);
2183}
2184EXPORT_SYMBOL(pcie_relaxed_ordering_enabled);
2185
2186static void pci_configure_relaxed_ordering(struct pci_dev *dev)
2187{
2188	struct pci_dev *root;
2189
2190	/* PCI_EXP_DEVCTL_RELAX_EN is RsvdP in VFs */
2191	if (dev->is_virtfn)
2192		return;
2193
2194	if (!pcie_relaxed_ordering_enabled(dev))
2195		return;
2196
2197	/*
2198	 * For now, we only deal with Relaxed Ordering issues with Root
2199	 * Ports. Peer-to-Peer DMA is another can of worms.
2200	 */
2201	root = pcie_find_root_port(dev);
2202	if (!root)
2203		return;
2204
2205	if (root->dev_flags & PCI_DEV_FLAGS_NO_RELAXED_ORDERING) {
2206		pcie_capability_clear_word(dev, PCI_EXP_DEVCTL,
2207					   PCI_EXP_DEVCTL_RELAX_EN);
2208		pci_info(dev, "Relaxed Ordering disabled because the Root Port didn't support it\n");
2209	}
2210}
2211
2212static void pci_configure_ltr(struct pci_dev *dev)
2213{
2214#ifdef CONFIG_PCIEASPM
2215	struct pci_host_bridge *host = pci_find_host_bridge(dev->bus);
2216	struct pci_dev *bridge;
2217	u32 cap, ctl;
2218
2219	if (!pci_is_pcie(dev))
2220		return;
2221
2222	/* Read L1 PM substate capabilities */
2223	dev->l1ss = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_L1SS);
2224
2225	pcie_capability_read_dword(dev, PCI_EXP_DEVCAP2, &cap);
2226	if (!(cap & PCI_EXP_DEVCAP2_LTR))
2227		return;
2228
2229	pcie_capability_read_dword(dev, PCI_EXP_DEVCTL2, &ctl);
2230	if (ctl & PCI_EXP_DEVCTL2_LTR_EN) {
2231		if (pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT) {
2232			dev->ltr_path = 1;
2233			return;
2234		}
2235
2236		bridge = pci_upstream_bridge(dev);
2237		if (bridge && bridge->ltr_path)
2238			dev->ltr_path = 1;
2239
2240		return;
2241	}
2242
2243	if (!host->native_ltr)
2244		return;
2245
2246	/*
2247	 * Software must not enable LTR in an Endpoint unless the Root
2248	 * Complex and all intermediate Switches indicate support for LTR.
2249	 * PCIe r4.0, sec 6.18.
2250	 */
2251	if (pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT) {
2252		pcie_capability_set_word(dev, PCI_EXP_DEVCTL2,
2253					 PCI_EXP_DEVCTL2_LTR_EN);
2254		dev->ltr_path = 1;
2255		return;
2256	}
2257
2258	/*
2259	 * If we're configuring a hot-added device, LTR was likely
2260	 * disabled in the upstream bridge, so re-enable it before enabling
2261	 * it in the new device.
2262	 */
2263	bridge = pci_upstream_bridge(dev);
2264	if (bridge && bridge->ltr_path) {
2265		pci_bridge_reconfigure_ltr(dev);
2266		pcie_capability_set_word(dev, PCI_EXP_DEVCTL2,
2267					 PCI_EXP_DEVCTL2_LTR_EN);
2268		dev->ltr_path = 1;
2269	}
2270#endif
2271}
2272
2273static void pci_configure_eetlp_prefix(struct pci_dev *dev)
2274{
2275#ifdef CONFIG_PCI_PASID
2276	struct pci_dev *bridge;
2277	int pcie_type;
2278	u32 cap;
2279
2280	if (!pci_is_pcie(dev))
2281		return;
2282
2283	pcie_capability_read_dword(dev, PCI_EXP_DEVCAP2, &cap);
2284	if (!(cap & PCI_EXP_DEVCAP2_EE_PREFIX))
2285		return;
2286
2287	pcie_type = pci_pcie_type(dev);
2288	if (pcie_type == PCI_EXP_TYPE_ROOT_PORT ||
2289	    pcie_type == PCI_EXP_TYPE_RC_END)
2290		dev->eetlp_prefix_path = 1;
2291	else {
2292		bridge = pci_upstream_bridge(dev);
2293		if (bridge && bridge->eetlp_prefix_path)
2294			dev->eetlp_prefix_path = 1;
2295	}
2296#endif
2297}
2298
2299static void pci_configure_serr(struct pci_dev *dev)
2300{
2301	u16 control;
2302
2303	if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
2304
2305		/*
2306		 * A bridge will not forward ERR_ messages coming from an
2307		 * endpoint unless SERR# forwarding is enabled.
2308		 */
2309		pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &control);
2310		if (!(control & PCI_BRIDGE_CTL_SERR)) {
2311			control |= PCI_BRIDGE_CTL_SERR;
2312			pci_write_config_word(dev, PCI_BRIDGE_CONTROL, control);
2313		}
2314	}
2315}
2316
2317static void pci_configure_device(struct pci_dev *dev)
2318{
2319	pci_configure_mps(dev);
2320	pci_configure_extended_tags(dev, NULL);
2321	pci_configure_relaxed_ordering(dev);
2322	pci_configure_ltr(dev);
2323	pci_configure_eetlp_prefix(dev);
2324	pci_configure_serr(dev);
2325
2326	pci_acpi_program_hp_params(dev);
2327}
2328
2329static void pci_release_capabilities(struct pci_dev *dev)
2330{
2331	pci_aer_exit(dev);
2332	pci_rcec_exit(dev);
2333	pci_iov_release(dev);
2334	pci_free_cap_save_buffers(dev);
2335}
2336
2337/**
2338 * pci_release_dev - Free a PCI device structure when all users of it are
2339 *		     finished
2340 * @dev: device that's been disconnected
2341 *
2342 * Will be called only by the device core when all users of this PCI device are
2343 * done.
2344 */
2345static void pci_release_dev(struct device *dev)
2346{
2347	struct pci_dev *pci_dev;
2348
2349	pci_dev = to_pci_dev(dev);
2350	pci_release_capabilities(pci_dev);
2351	pci_release_of_node(pci_dev);
2352	pcibios_release_device(pci_dev);
2353	pci_bus_put(pci_dev->bus);
2354	kfree(pci_dev->driver_override);
2355	bitmap_free(pci_dev->dma_alias_mask);
2356	dev_dbg(dev, "device released\n");
2357	kfree(pci_dev);
2358}
2359
2360struct pci_dev *pci_alloc_dev(struct pci_bus *bus)
2361{
2362	struct pci_dev *dev;
2363
2364	dev = kzalloc(sizeof(struct pci_dev), GFP_KERNEL);
2365	if (!dev)
2366		return NULL;
2367
2368	INIT_LIST_HEAD(&dev->bus_list);
2369	dev->dev.type = &pci_dev_type;
2370	dev->bus = pci_bus_get(bus);
2371	dev->driver_exclusive_resource = (struct resource) {
2372		.name = "PCI Exclusive",
2373		.start = 0,
2374		.end = -1,
2375	};
2376
2377	spin_lock_init(&dev->pcie_cap_lock);
2378#ifdef CONFIG_PCI_MSI
2379	raw_spin_lock_init(&dev->msi_lock);
2380#endif
2381	return dev;
2382}
2383EXPORT_SYMBOL(pci_alloc_dev);
2384
2385static bool pci_bus_crs_vendor_id(u32 l)
2386{
2387	return (l & 0xffff) == PCI_VENDOR_ID_PCI_SIG;
2388}
2389
2390static bool pci_bus_wait_crs(struct pci_bus *bus, int devfn, u32 *l,
2391			     int timeout)
2392{
2393	int delay = 1;
2394
2395	if (!pci_bus_crs_vendor_id(*l))
2396		return true;	/* not a CRS completion */
2397
2398	if (!timeout)
2399		return false;	/* CRS, but caller doesn't want to wait */
2400
2401	/*
2402	 * We got the reserved Vendor ID that indicates a completion with
2403	 * Configuration Request Retry Status (CRS).  Retry until we get a
2404	 * valid Vendor ID or we time out.
2405	 */
2406	while (pci_bus_crs_vendor_id(*l)) {
2407		if (delay > timeout) {
2408			pr_warn("pci %04x:%02x:%02x.%d: not ready after %dms; giving up\n",
2409				pci_domain_nr(bus), bus->number,
2410				PCI_SLOT(devfn), PCI_FUNC(devfn), delay - 1);
2411
 
 
 
2412			return false;
2413		}
2414		if (delay >= 1000)
2415			pr_info("pci %04x:%02x:%02x.%d: not ready after %dms; waiting\n",
2416				pci_domain_nr(bus), bus->number,
2417				PCI_SLOT(devfn), PCI_FUNC(devfn), delay - 1);
2418
2419		msleep(delay);
2420		delay *= 2;
2421
2422		if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
2423			return false;
 
 
 
 
 
 
 
 
2424	}
2425
2426	if (delay >= 1000)
2427		pr_info("pci %04x:%02x:%02x.%d: ready after %dms\n",
2428			pci_domain_nr(bus), bus->number,
2429			PCI_SLOT(devfn), PCI_FUNC(devfn), delay - 1);
2430
2431	return true;
2432}
2433
2434bool pci_bus_generic_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l,
2435					int timeout)
2436{
2437	if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
2438		return false;
2439
2440	/* Some broken boards return 0 or ~0 (PCI_ERROR_RESPONSE) if a slot is empty: */
2441	if (PCI_POSSIBLE_ERROR(*l) || *l == 0x00000000 ||
2442	    *l == 0x0000ffff || *l == 0xffff0000)
2443		return false;
2444
2445	if (pci_bus_crs_vendor_id(*l))
2446		return pci_bus_wait_crs(bus, devfn, l, timeout);
2447
2448	return true;
2449}
2450
2451bool pci_bus_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l,
2452				int timeout)
2453{
2454#ifdef CONFIG_PCI_QUIRKS
2455	struct pci_dev *bridge = bus->self;
2456
2457	/*
2458	 * Certain IDT switches have an issue where they improperly trigger
2459	 * ACS Source Validation errors on completions for config reads.
2460	 */
2461	if (bridge && bridge->vendor == PCI_VENDOR_ID_IDT &&
2462	    bridge->device == 0x80b5)
2463		return pci_idt_bus_quirk(bus, devfn, l, timeout);
2464#endif
2465
2466	return pci_bus_generic_read_dev_vendor_id(bus, devfn, l, timeout);
2467}
2468EXPORT_SYMBOL(pci_bus_read_dev_vendor_id);
2469
2470/*
2471 * Read the config data for a PCI device, sanity-check it,
2472 * and fill in the dev structure.
2473 */
2474static struct pci_dev *pci_scan_device(struct pci_bus *bus, int devfn)
2475{
2476	struct pci_dev *dev;
2477	u32 l;
2478
2479	if (!pci_bus_read_dev_vendor_id(bus, devfn, &l, 60*1000))
2480		return NULL;
2481
2482	dev = pci_alloc_dev(bus);
2483	if (!dev)
2484		return NULL;
2485
2486	dev->devfn = devfn;
2487	dev->vendor = l & 0xffff;
2488	dev->device = (l >> 16) & 0xffff;
2489
 
 
2490	if (pci_setup_device(dev)) {
2491		pci_bus_put(dev->bus);
2492		kfree(dev);
2493		return NULL;
2494	}
2495
2496	return dev;
2497}
2498
2499void pcie_report_downtraining(struct pci_dev *dev)
2500{
2501	if (!pci_is_pcie(dev))
2502		return;
2503
2504	/* Look from the device up to avoid downstream ports with no devices */
2505	if ((pci_pcie_type(dev) != PCI_EXP_TYPE_ENDPOINT) &&
2506	    (pci_pcie_type(dev) != PCI_EXP_TYPE_LEG_END) &&
2507	    (pci_pcie_type(dev) != PCI_EXP_TYPE_UPSTREAM))
2508		return;
2509
2510	/* Multi-function PCIe devices share the same link/status */
2511	if (PCI_FUNC(dev->devfn) != 0 || dev->is_virtfn)
2512		return;
2513
2514	/* Print link status only if the device is constrained by the fabric */
2515	__pcie_print_link_status(dev, false);
2516}
2517
2518static void pci_init_capabilities(struct pci_dev *dev)
2519{
2520	pci_ea_init(dev);		/* Enhanced Allocation */
2521	pci_msi_init(dev);		/* Disable MSI */
2522	pci_msix_init(dev);		/* Disable MSI-X */
2523
2524	/* Buffers for saving PCIe and PCI-X capabilities */
2525	pci_allocate_cap_save_buffers(dev);
2526
2527	pci_pm_init(dev);		/* Power Management */
2528	pci_vpd_init(dev);		/* Vital Product Data */
2529	pci_configure_ari(dev);		/* Alternative Routing-ID Forwarding */
2530	pci_iov_init(dev);		/* Single Root I/O Virtualization */
2531	pci_ats_init(dev);		/* Address Translation Services */
2532	pci_pri_init(dev);		/* Page Request Interface */
2533	pci_pasid_init(dev);		/* Process Address Space ID */
2534	pci_acs_init(dev);		/* Access Control Services */
2535	pci_ptm_init(dev);		/* Precision Time Measurement */
2536	pci_aer_init(dev);		/* Advanced Error Reporting */
2537	pci_dpc_init(dev);		/* Downstream Port Containment */
2538	pci_rcec_init(dev);		/* Root Complex Event Collector */
2539	pci_doe_init(dev);		/* Data Object Exchange */
2540
2541	pcie_report_downtraining(dev);
2542	pci_init_reset_methods(dev);
2543}
2544
2545/*
2546 * This is the equivalent of pci_host_bridge_msi_domain() that acts on
2547 * devices. Firmware interfaces that can select the MSI domain on a
2548 * per-device basis should be called from here.
2549 */
2550static struct irq_domain *pci_dev_msi_domain(struct pci_dev *dev)
2551{
2552	struct irq_domain *d;
2553
2554	/*
2555	 * If a domain has been set through the pcibios_device_add()
2556	 * callback, then this is the one (platform code knows best).
2557	 */
2558	d = dev_get_msi_domain(&dev->dev);
2559	if (d)
2560		return d;
2561
2562	/*
2563	 * Let's see if we have a firmware interface able to provide
2564	 * the domain.
2565	 */
2566	d = pci_msi_get_device_domain(dev);
2567	if (d)
2568		return d;
2569
2570	return NULL;
2571}
2572
2573static void pci_set_msi_domain(struct pci_dev *dev)
2574{
2575	struct irq_domain *d;
2576
2577	/*
2578	 * If the platform or firmware interfaces cannot supply a
2579	 * device-specific MSI domain, then inherit the default domain
2580	 * from the host bridge itself.
2581	 */
2582	d = pci_dev_msi_domain(dev);
2583	if (!d)
2584		d = dev_get_msi_domain(&dev->bus->dev);
2585
2586	dev_set_msi_domain(&dev->dev, d);
 
2587}
2588
2589void pci_device_add(struct pci_dev *dev, struct pci_bus *bus)
2590{
2591	int ret;
2592
2593	pci_configure_device(dev);
2594
2595	device_initialize(&dev->dev);
2596	dev->dev.release = pci_release_dev;
2597
2598	set_dev_node(&dev->dev, pcibus_to_node(bus));
2599	dev->dev.dma_mask = &dev->dma_mask;
2600	dev->dev.dma_parms = &dev->dma_parms;
2601	dev->dev.coherent_dma_mask = 0xffffffffull;
2602
2603	dma_set_max_seg_size(&dev->dev, 65536);
2604	dma_set_seg_boundary(&dev->dev, 0xffffffff);
2605
2606	pcie_failed_link_retrain(dev);
2607
2608	/* Fix up broken headers */
2609	pci_fixup_device(pci_fixup_header, dev);
2610
 
2611	pci_reassigndev_resource_alignment(dev);
2612
 
2613	dev->state_saved = false;
2614
 
2615	pci_init_capabilities(dev);
2616
2617	/*
2618	 * Add the device to our list of discovered devices
2619	 * and the bus list for fixup functions, etc.
2620	 */
2621	down_write(&pci_bus_sem);
2622	list_add_tail(&dev->bus_list, &bus->devices);
2623	up_write(&pci_bus_sem);
2624
2625	ret = pcibios_device_add(dev);
2626	WARN_ON(ret < 0);
2627
2628	/* Set up MSI IRQ domain */
2629	pci_set_msi_domain(dev);
2630
2631	/* Notifier could use PCI capabilities */
2632	dev->match_driver = false;
2633	ret = device_add(&dev->dev);
2634	WARN_ON(ret < 0);
2635}
2636
2637struct pci_dev *pci_scan_single_device(struct pci_bus *bus, int devfn)
2638{
2639	struct pci_dev *dev;
2640
2641	dev = pci_get_slot(bus, devfn);
2642	if (dev) {
2643		pci_dev_put(dev);
2644		return dev;
2645	}
2646
2647	dev = pci_scan_device(bus, devfn);
2648	if (!dev)
2649		return NULL;
2650
2651	pci_device_add(dev, bus);
2652
2653	return dev;
2654}
2655EXPORT_SYMBOL(pci_scan_single_device);
2656
2657static int next_ari_fn(struct pci_bus *bus, struct pci_dev *dev, int fn)
2658{
2659	int pos;
2660	u16 cap = 0;
2661	unsigned int next_fn;
2662
2663	if (!dev)
2664		return -ENODEV;
2665
2666	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI);
2667	if (!pos)
2668		return -ENODEV;
2669
2670	pci_read_config_word(dev, pos + PCI_ARI_CAP, &cap);
2671	next_fn = PCI_ARI_CAP_NFN(cap);
2672	if (next_fn <= fn)
2673		return -ENODEV;	/* protect against malformed list */
2674
2675	return next_fn;
2676}
2677
2678static int next_fn(struct pci_bus *bus, struct pci_dev *dev, int fn)
2679{
2680	if (pci_ari_enabled(bus))
2681		return next_ari_fn(bus, dev, fn);
2682
2683	if (fn >= 7)
2684		return -ENODEV;
2685	/* only multifunction devices may have more functions */
2686	if (dev && !dev->multifunction)
2687		return -ENODEV;
 
 
 
 
 
 
 
 
 
 
 
 
 
2688
2689	return fn + 1;
2690}
2691
2692static int only_one_child(struct pci_bus *bus)
2693{
2694	struct pci_dev *bridge = bus->self;
2695
2696	/*
2697	 * Systems with unusual topologies set PCI_SCAN_ALL_PCIE_DEVS so
2698	 * we scan for all possible devices, not just Device 0.
2699	 */
2700	if (pci_has_flag(PCI_SCAN_ALL_PCIE_DEVS))
2701		return 0;
2702
2703	/*
2704	 * A PCIe Downstream Port normally leads to a Link with only Device
2705	 * 0 on it (PCIe spec r3.1, sec 7.3.1).  As an optimization, scan
2706	 * only for Device 0 in that situation.
2707	 */
2708	if (bridge && pci_is_pcie(bridge) && pcie_downstream_port(bridge))
2709		return 1;
2710
2711	return 0;
2712}
2713
2714/**
2715 * pci_scan_slot - Scan a PCI slot on a bus for devices
2716 * @bus: PCI bus to scan
2717 * @devfn: slot number to scan (must have zero function)
2718 *
2719 * Scan a PCI slot on the specified PCI bus for devices, adding
2720 * discovered devices to the @bus->devices list.  New devices
2721 * will not have is_added set.
2722 *
2723 * Returns the number of new devices found.
2724 */
2725int pci_scan_slot(struct pci_bus *bus, int devfn)
2726{
 
2727	struct pci_dev *dev;
2728	int fn = 0, nr = 0;
2729
2730	if (only_one_child(bus) && (devfn > 0))
2731		return 0; /* Already scanned the entire slot */
2732
2733	do {
 
 
 
 
 
 
2734		dev = pci_scan_single_device(bus, devfn + fn);
2735		if (dev) {
2736			if (!pci_dev_is_added(dev))
2737				nr++;
2738			if (fn > 0)
2739				dev->multifunction = 1;
2740		} else if (fn == 0) {
2741			/*
2742			 * Function 0 is required unless we are running on
2743			 * a hypervisor that passes through individual PCI
2744			 * functions.
2745			 */
2746			if (!hypervisor_isolated_pci_functions())
2747				break;
2748		}
2749		fn = next_fn(bus, dev, fn);
2750	} while (fn >= 0);
2751
2752	/* Only one slot has PCIe device */
2753	if (bus->self && nr)
2754		pcie_aspm_init_link_state(bus->self);
2755
2756	return nr;
2757}
2758EXPORT_SYMBOL(pci_scan_slot);
2759
2760static int pcie_find_smpss(struct pci_dev *dev, void *data)
2761{
2762	u8 *smpss = data;
2763
2764	if (!pci_is_pcie(dev))
2765		return 0;
2766
2767	/*
2768	 * We don't have a way to change MPS settings on devices that have
2769	 * drivers attached.  A hot-added device might support only the minimum
2770	 * MPS setting (MPS=128).  Therefore, if the fabric contains a bridge
2771	 * where devices may be hot-added, we limit the fabric MPS to 128 so
2772	 * hot-added devices will work correctly.
2773	 *
2774	 * However, if we hot-add a device to a slot directly below a Root
2775	 * Port, it's impossible for there to be other existing devices below
2776	 * the port.  We don't limit the MPS in this case because we can
2777	 * reconfigure MPS on both the Root Port and the hot-added device,
2778	 * and there are no other devices involved.
2779	 *
2780	 * Note that this PCIE_BUS_SAFE path assumes no peer-to-peer DMA.
2781	 */
2782	if (dev->is_hotplug_bridge &&
2783	    pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT)
2784		*smpss = 0;
2785
2786	if (*smpss > dev->pcie_mpss)
2787		*smpss = dev->pcie_mpss;
2788
2789	return 0;
2790}
2791
2792static void pcie_write_mps(struct pci_dev *dev, int mps)
2793{
2794	int rc;
2795
2796	if (pcie_bus_config == PCIE_BUS_PERFORMANCE) {
2797		mps = 128 << dev->pcie_mpss;
2798
2799		if (pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT &&
2800		    dev->bus->self)
2801
2802			/*
2803			 * For "Performance", the assumption is made that
2804			 * downstream communication will never be larger than
2805			 * the MRRS.  So, the MPS only needs to be configured
2806			 * for the upstream communication.  This being the case,
2807			 * walk from the top down and set the MPS of the child
2808			 * to that of the parent bus.
2809			 *
2810			 * Configure the device MPS with the smaller of the
2811			 * device MPSS or the bridge MPS (which is assumed to be
2812			 * properly configured at this point to the largest
2813			 * allowable MPS based on its parent bus).
2814			 */
2815			mps = min(mps, pcie_get_mps(dev->bus->self));
2816	}
2817
2818	rc = pcie_set_mps(dev, mps);
2819	if (rc)
2820		pci_err(dev, "Failed attempting to set the MPS\n");
2821}
2822
2823static void pcie_write_mrrs(struct pci_dev *dev)
2824{
2825	int rc, mrrs;
2826
2827	/*
2828	 * In the "safe" case, do not configure the MRRS.  There appear to be
2829	 * issues with setting MRRS to 0 on a number of devices.
2830	 */
2831	if (pcie_bus_config != PCIE_BUS_PERFORMANCE)
2832		return;
2833
2834	/*
2835	 * For max performance, the MRRS must be set to the largest supported
2836	 * value.  However, it cannot be configured larger than the MPS the
2837	 * device or the bus can support.  This should already be properly
2838	 * configured by a prior call to pcie_write_mps().
2839	 */
2840	mrrs = pcie_get_mps(dev);
2841
2842	/*
2843	 * MRRS is a R/W register.  Invalid values can be written, but a
2844	 * subsequent read will verify if the value is acceptable or not.
2845	 * If the MRRS value provided is not acceptable (e.g., too large),
2846	 * shrink the value until it is acceptable to the HW.
2847	 */
2848	while (mrrs != pcie_get_readrq(dev) && mrrs >= 128) {
2849		rc = pcie_set_readrq(dev, mrrs);
2850		if (!rc)
2851			break;
2852
2853		pci_warn(dev, "Failed attempting to set the MRRS\n");
2854		mrrs /= 2;
2855	}
2856
2857	if (mrrs < 128)
2858		pci_err(dev, "MRRS was unable to be configured with a safe value.  If problems are experienced, try running with pci=pcie_bus_safe\n");
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2859}
2860
2861static int pcie_bus_configure_set(struct pci_dev *dev, void *data)
2862{
2863	int mps, orig_mps;
2864
2865	if (!pci_is_pcie(dev))
2866		return 0;
2867
2868	if (pcie_bus_config == PCIE_BUS_TUNE_OFF ||
2869	    pcie_bus_config == PCIE_BUS_DEFAULT)
2870		return 0;
 
2871
2872	mps = 128 << *(u8 *)data;
2873	orig_mps = pcie_get_mps(dev);
2874
2875	pcie_write_mps(dev, mps);
2876	pcie_write_mrrs(dev);
2877
2878	pci_info(dev, "Max Payload Size set to %4d/%4d (was %4d), Max Read Rq %4d\n",
2879		 pcie_get_mps(dev), 128 << dev->pcie_mpss,
2880		 orig_mps, pcie_get_readrq(dev));
2881
2882	return 0;
2883}
2884
2885/*
2886 * pcie_bus_configure_settings() requires that pci_walk_bus work in a top-down,
2887 * parents then children fashion.  If this changes, then this code will not
2888 * work as designed.
2889 */
2890void pcie_bus_configure_settings(struct pci_bus *bus)
2891{
2892	u8 smpss = 0;
2893
2894	if (!bus->self)
2895		return;
2896
2897	if (!pci_is_pcie(bus->self))
2898		return;
2899
2900	/*
2901	 * FIXME - Peer to peer DMA is possible, though the endpoint would need
2902	 * to be aware of the MPS of the destination.  To work around this,
2903	 * simply force the MPS of the entire system to the smallest possible.
2904	 */
2905	if (pcie_bus_config == PCIE_BUS_PEER2PEER)
2906		smpss = 0;
2907
2908	if (pcie_bus_config == PCIE_BUS_SAFE) {
2909		smpss = bus->self->pcie_mpss;
2910
2911		pcie_find_smpss(bus->self, &smpss);
2912		pci_walk_bus(bus, pcie_find_smpss, &smpss);
2913	}
2914
2915	pcie_bus_configure_set(bus->self, &smpss);
2916	pci_walk_bus(bus, pcie_bus_configure_set, &smpss);
2917}
2918EXPORT_SYMBOL_GPL(pcie_bus_configure_settings);
2919
2920/*
2921 * Called after each bus is probed, but before its children are examined.  This
2922 * is marked as __weak because multiple architectures define it.
2923 */
2924void __weak pcibios_fixup_bus(struct pci_bus *bus)
2925{
2926       /* nothing to do, expected to be removed in the future */
2927}
2928
2929/**
2930 * pci_scan_child_bus_extend() - Scan devices below a bus
2931 * @bus: Bus to scan for devices
2932 * @available_buses: Total number of buses available (%0 does not try to
2933 *		     extend beyond the minimal)
2934 *
2935 * Scans devices below @bus including subordinate buses. Returns new
2936 * subordinate number including all the found devices. Passing
2937 * @available_buses causes the remaining bus space to be distributed
2938 * equally between hotplug-capable bridges to allow future extension of the
2939 * hierarchy.
2940 */
2941static unsigned int pci_scan_child_bus_extend(struct pci_bus *bus,
2942					      unsigned int available_buses)
2943{
2944	unsigned int used_buses, normal_bridges = 0, hotplug_bridges = 0;
2945	unsigned int start = bus->busn_res.start;
2946	unsigned int devfn, cmax, max = start;
2947	struct pci_dev *dev;
2948
2949	dev_dbg(&bus->dev, "scanning bus\n");
2950
2951	/* Go find them, Rover! */
2952	for (devfn = 0; devfn < 256; devfn += 8)
2953		pci_scan_slot(bus, devfn);
2954
2955	/* Reserve buses for SR-IOV capability */
2956	used_buses = pci_iov_bus_range(bus);
2957	max += used_buses;
2958
2959	/*
2960	 * After performing arch-dependent fixup of the bus, look behind
2961	 * all PCI-to-PCI bridges on this bus.
2962	 */
2963	if (!bus->is_added) {
2964		dev_dbg(&bus->dev, "fixups for bus\n");
2965		pcibios_fixup_bus(bus);
2966		bus->is_added = 1;
2967	}
2968
2969	/*
2970	 * Calculate how many hotplug bridges and normal bridges there
2971	 * are on this bus. We will distribute the additional available
2972	 * buses between hotplug bridges.
2973	 */
2974	for_each_pci_bridge(dev, bus) {
2975		if (dev->is_hotplug_bridge)
2976			hotplug_bridges++;
2977		else
2978			normal_bridges++;
2979	}
2980
2981	/*
2982	 * Scan bridges that are already configured. We don't touch them
2983	 * unless they are misconfigured (which will be done in the second
2984	 * scan below).
2985	 */
2986	for_each_pci_bridge(dev, bus) {
2987		cmax = max;
2988		max = pci_scan_bridge_extend(bus, dev, max, 0, 0);
2989
2990		/*
2991		 * Reserve one bus for each bridge now to avoid extending
2992		 * hotplug bridges too much during the second scan below.
2993		 */
2994		used_buses++;
2995		if (max - cmax > 1)
2996			used_buses += max - cmax - 1;
2997	}
2998
2999	/* Scan bridges that need to be reconfigured */
3000	for_each_pci_bridge(dev, bus) {
3001		unsigned int buses = 0;
3002
3003		if (!hotplug_bridges && normal_bridges == 1) {
3004			/*
3005			 * There is only one bridge on the bus (upstream
3006			 * port) so it gets all available buses which it
3007			 * can then distribute to the possible hotplug
3008			 * bridges below.
3009			 */
3010			buses = available_buses;
3011		} else if (dev->is_hotplug_bridge) {
3012			/*
3013			 * Distribute the extra buses between hotplug
3014			 * bridges if any.
3015			 */
3016			buses = available_buses / hotplug_bridges;
3017			buses = min(buses, available_buses - used_buses + 1);
3018		}
3019
3020		cmax = max;
3021		max = pci_scan_bridge_extend(bus, dev, cmax, buses, 1);
3022		/* One bus is already accounted so don't add it again */
3023		if (max - cmax > 1)
3024			used_buses += max - cmax - 1;
3025	}
3026
3027	/*
3028	 * Make sure a hotplug bridge has at least the minimum requested
3029	 * number of buses but allow it to grow up to the maximum available
3030	 * bus number if there is room.
3031	 */
3032	if (bus->self && bus->self->is_hotplug_bridge) {
3033		used_buses = max_t(unsigned int, available_buses,
3034				   pci_hotplug_bus_size - 1);
3035		if (max - start < used_buses) {
3036			max = start + used_buses;
3037
3038			/* Do not allocate more buses than we have room left */
3039			if (max > bus->busn_res.end)
3040				max = bus->busn_res.end;
3041
3042			dev_dbg(&bus->dev, "%pR extended by %#02x\n",
3043				&bus->busn_res, max - start);
3044		}
3045	}
3046
3047	/*
3048	 * We've scanned the bus and so we know all about what's on
3049	 * the other side of any bridges that may be on this bus plus
3050	 * any devices.
3051	 *
3052	 * Return how far we've got finding sub-buses.
3053	 */
3054	dev_dbg(&bus->dev, "bus scan returning with max=%02x\n", max);
3055	return max;
3056}
3057
3058/**
3059 * pci_scan_child_bus() - Scan devices below a bus
3060 * @bus: Bus to scan for devices
3061 *
3062 * Scans devices below @bus including subordinate buses. Returns new
3063 * subordinate number including all the found devices.
3064 */
3065unsigned int pci_scan_child_bus(struct pci_bus *bus)
3066{
3067	return pci_scan_child_bus_extend(bus, 0);
3068}
3069EXPORT_SYMBOL_GPL(pci_scan_child_bus);
3070
3071/**
3072 * pcibios_root_bridge_prepare - Platform-specific host bridge setup
3073 * @bridge: Host bridge to set up
3074 *
3075 * Default empty implementation.  Replace with an architecture-specific setup
3076 * routine, if necessary.
3077 */
3078int __weak pcibios_root_bridge_prepare(struct pci_host_bridge *bridge)
3079{
3080	return 0;
3081}
3082
3083void __weak pcibios_add_bus(struct pci_bus *bus)
3084{
3085}
3086
3087void __weak pcibios_remove_bus(struct pci_bus *bus)
3088{
3089}
3090
3091struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
3092		struct pci_ops *ops, void *sysdata, struct list_head *resources)
3093{
3094	int error;
3095	struct pci_host_bridge *bridge;
 
 
 
 
 
 
3096
3097	bridge = pci_alloc_host_bridge(0);
3098	if (!bridge)
3099		return NULL;
3100
3101	bridge->dev.parent = parent;
 
 
 
 
 
 
 
 
3102
3103	list_splice_init(resources, &bridge->windows);
3104	bridge->sysdata = sysdata;
3105	bridge->busnr = bus;
3106	bridge->ops = ops;
3107
3108	error = pci_register_host_bridge(bridge);
3109	if (error < 0)
 
 
 
 
3110		goto err_out;
 
3111
3112	return bridge->bus;
 
 
 
 
 
 
 
3113
3114err_out:
3115	put_device(&bridge->dev);
3116	return NULL;
3117}
3118EXPORT_SYMBOL_GPL(pci_create_root_bus);
3119
3120int pci_host_probe(struct pci_host_bridge *bridge)
3121{
3122	struct pci_bus *bus, *child;
3123	int ret;
 
 
3124
3125	ret = pci_scan_root_bus_bridge(bridge);
3126	if (ret < 0) {
3127		dev_err(bridge->dev.parent, "Scanning root bridge failed");
3128		return ret;
3129	}
3130
3131	bus = bridge->bus;
 
3132
3133	/*
3134	 * We insert PCI resources into the iomem_resource and
3135	 * ioport_resource trees in either pci_bus_claim_resources()
3136	 * or pci_bus_assign_resources().
3137	 */
3138	if (pci_has_flag(PCI_PROBE_ONLY)) {
3139		pci_bus_claim_resources(bus);
3140	} else {
3141		pci_bus_size_bridges(bus);
3142		pci_bus_assign_resources(bus);
3143
3144		list_for_each_entry(child, &bus->children, node)
3145			pcie_bus_configure_settings(child);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3146	}
3147
3148	pci_bus_add_devices(bus);
3149	return 0;
 
 
 
 
 
 
 
 
 
 
3150}
3151EXPORT_SYMBOL_GPL(pci_host_probe);
3152
3153int pci_bus_insert_busn_res(struct pci_bus *b, int bus, int bus_max)
3154{
3155	struct resource *res = &b->busn_res;
3156	struct resource *parent_res, *conflict;
3157
3158	res->start = bus;
3159	res->end = bus_max;
3160	res->flags = IORESOURCE_BUS;
3161
3162	if (!pci_is_root_bus(b))
3163		parent_res = &b->parent->busn_res;
3164	else {
3165		parent_res = get_pci_domain_busn_res(pci_domain_nr(b));
3166		res->flags |= IORESOURCE_PCI_FIXED;
3167	}
3168
3169	conflict = request_resource_conflict(parent_res, res);
3170
3171	if (conflict)
3172		dev_info(&b->dev,
3173			   "busn_res: can not insert %pR under %s%pR (conflicts with %s %pR)\n",
3174			    res, pci_is_root_bus(b) ? "domain " : "",
3175			    parent_res, conflict->name, conflict);
3176
3177	return conflict == NULL;
3178}
3179
3180int pci_bus_update_busn_res_end(struct pci_bus *b, int bus_max)
3181{
3182	struct resource *res = &b->busn_res;
3183	struct resource old_res = *res;
3184	resource_size_t size;
3185	int ret;
3186
3187	if (res->start > bus_max)
3188		return -EINVAL;
3189
3190	size = bus_max - res->start + 1;
3191	ret = adjust_resource(res, res->start, size);
3192	dev_info(&b->dev, "busn_res: %pR end %s updated to %02x\n",
 
3193			&old_res, ret ? "can not be" : "is", bus_max);
3194
3195	if (!ret && !res->parent)
3196		pci_bus_insert_busn_res(b, res->start, res->end);
3197
3198	return ret;
3199}
3200
3201void pci_bus_release_busn_res(struct pci_bus *b)
3202{
3203	struct resource *res = &b->busn_res;
3204	int ret;
3205
3206	if (!res->flags || !res->parent)
3207		return;
3208
3209	ret = release_resource(res);
3210	dev_info(&b->dev, "busn_res: %pR %s released\n",
 
3211			res, ret ? "can not be" : "is");
3212}
3213
3214int pci_scan_root_bus_bridge(struct pci_host_bridge *bridge)
3215{
3216	struct resource_entry *window;
3217	bool found = false;
3218	struct pci_bus *b;
3219	int max, bus, ret;
3220
3221	if (!bridge)
3222		return -EINVAL;
3223
3224	resource_list_for_each_entry(window, &bridge->windows)
3225		if (window->res->flags & IORESOURCE_BUS) {
3226			bridge->busnr = window->res->start;
3227			found = true;
3228			break;
3229		}
3230
3231	ret = pci_register_host_bridge(bridge);
3232	if (ret < 0)
3233		return ret;
3234
3235	b = bridge->bus;
3236	bus = bridge->busnr;
3237
3238	if (!found) {
3239		dev_info(&b->dev,
3240		 "No busn resource found for root bus, will use [bus %02x-ff]\n",
3241			bus);
3242		pci_bus_insert_busn_res(b, bus, 255);
3243	}
3244
3245	max = pci_scan_child_bus(b);
3246
3247	if (!found)
3248		pci_bus_update_busn_res_end(b, max);
3249
3250	return 0;
3251}
3252EXPORT_SYMBOL(pci_scan_root_bus_bridge);
3253
3254struct pci_bus *pci_scan_root_bus(struct device *parent, int bus,
3255		struct pci_ops *ops, void *sysdata, struct list_head *resources)
3256{
3257	struct resource_entry *window;
3258	bool found = false;
3259	struct pci_bus *b;
3260	int max;
3261
3262	resource_list_for_each_entry(window, resources)
3263		if (window->res->flags & IORESOURCE_BUS) {
3264			found = true;
3265			break;
3266		}
3267
3268	b = pci_create_root_bus(parent, bus, ops, sysdata, resources);
3269	if (!b)
3270		return NULL;
3271
3272	if (!found) {
3273		dev_info(&b->dev,
3274		 "No busn resource found for root bus, will use [bus %02x-ff]\n",
3275			bus);
3276		pci_bus_insert_busn_res(b, bus, 255);
3277	}
3278
3279	max = pci_scan_child_bus(b);
3280
3281	if (!found)
3282		pci_bus_update_busn_res_end(b, max);
3283
 
3284	return b;
3285}
3286EXPORT_SYMBOL(pci_scan_root_bus);
3287
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3288struct pci_bus *pci_scan_bus(int bus, struct pci_ops *ops,
3289					void *sysdata)
3290{
3291	LIST_HEAD(resources);
3292	struct pci_bus *b;
3293
3294	pci_add_resource(&resources, &ioport_resource);
3295	pci_add_resource(&resources, &iomem_resource);
3296	pci_add_resource(&resources, &busn_resource);
3297	b = pci_create_root_bus(NULL, bus, ops, sysdata, &resources);
3298	if (b) {
3299		pci_scan_child_bus(b);
 
3300	} else {
3301		pci_free_resource_list(&resources);
3302	}
3303	return b;
3304}
3305EXPORT_SYMBOL(pci_scan_bus);
3306
3307/**
3308 * pci_rescan_bus_bridge_resize - Scan a PCI bus for devices
3309 * @bridge: PCI bridge for the bus to scan
3310 *
3311 * Scan a PCI bus and child buses for new devices, add them,
3312 * and enable them, resizing bridge mmio/io resource if necessary
3313 * and possible.  The caller must ensure the child devices are already
3314 * removed for resizing to occur.
3315 *
3316 * Returns the max number of subordinate bus discovered.
3317 */
3318unsigned int pci_rescan_bus_bridge_resize(struct pci_dev *bridge)
3319{
3320	unsigned int max;
3321	struct pci_bus *bus = bridge->subordinate;
3322
3323	max = pci_scan_child_bus(bus);
3324
3325	pci_assign_unassigned_bridge_resources(bridge);
3326
3327	pci_bus_add_devices(bus);
3328
3329	return max;
3330}
3331
3332/**
3333 * pci_rescan_bus - Scan a PCI bus for devices
3334 * @bus: PCI bus to scan
3335 *
3336 * Scan a PCI bus and child buses for new devices, add them,
3337 * and enable them.
3338 *
3339 * Returns the max number of subordinate bus discovered.
3340 */
3341unsigned int pci_rescan_bus(struct pci_bus *bus)
3342{
3343	unsigned int max;
3344
3345	max = pci_scan_child_bus(bus);
3346	pci_assign_unassigned_bus_resources(bus);
3347	pci_bus_add_devices(bus);
3348
3349	return max;
3350}
3351EXPORT_SYMBOL_GPL(pci_rescan_bus);
3352
 
 
 
 
 
3353/*
3354 * pci_rescan_bus(), pci_rescan_bus_bridge_resize() and PCI device removal
3355 * routines should always be executed under this mutex.
3356 */
3357static DEFINE_MUTEX(pci_rescan_remove_lock);
3358
3359void pci_lock_rescan_remove(void)
3360{
3361	mutex_lock(&pci_rescan_remove_lock);
3362}
3363EXPORT_SYMBOL_GPL(pci_lock_rescan_remove);
3364
3365void pci_unlock_rescan_remove(void)
3366{
3367	mutex_unlock(&pci_rescan_remove_lock);
3368}
3369EXPORT_SYMBOL_GPL(pci_unlock_rescan_remove);
3370
3371static int __init pci_sort_bf_cmp(const struct device *d_a,
3372				  const struct device *d_b)
3373{
3374	const struct pci_dev *a = to_pci_dev(d_a);
3375	const struct pci_dev *b = to_pci_dev(d_b);
3376
3377	if      (pci_domain_nr(a->bus) < pci_domain_nr(b->bus)) return -1;
3378	else if (pci_domain_nr(a->bus) > pci_domain_nr(b->bus)) return  1;
3379
3380	if      (a->bus->number < b->bus->number) return -1;
3381	else if (a->bus->number > b->bus->number) return  1;
3382
3383	if      (a->devfn < b->devfn) return -1;
3384	else if (a->devfn > b->devfn) return  1;
3385
3386	return 0;
3387}
3388
3389void __init pci_sort_breadthfirst(void)
3390{
3391	bus_sort_breadthfirst(&pci_bus_type, &pci_sort_bf_cmp);
3392}
3393
3394int pci_hp_add_bridge(struct pci_dev *dev)
3395{
3396	struct pci_bus *parent = dev->bus;
3397	int busnr, start = parent->busn_res.start;
3398	unsigned int available_buses = 0;
3399	int end = parent->busn_res.end;
3400
3401	for (busnr = start; busnr <= end; busnr++) {
3402		if (!pci_find_bus(pci_domain_nr(parent), busnr))
3403			break;
3404	}
3405	if (busnr-- > end) {
3406		pci_err(dev, "No bus number available for hot-added bridge\n");
3407		return -1;
3408	}
3409
3410	/* Scan bridges that are already configured */
3411	busnr = pci_scan_bridge(parent, dev, busnr, 0);
3412
3413	/*
3414	 * Distribute the available bus numbers between hotplug-capable
3415	 * bridges to make extending the chain later possible.
3416	 */
3417	available_buses = end - busnr;
3418
3419	/* Scan bridges that need to be reconfigured */
3420	pci_scan_bridge_extend(parent, dev, busnr, available_buses, 1);
3421
3422	if (!dev->subordinate)
3423		return -1;
3424
3425	return 0;
3426}
3427EXPORT_SYMBOL_GPL(pci_hp_add_bridge);
v3.15
 
   1/*
   2 * probe.c - PCI detection and setup code
   3 */
   4
   5#include <linux/kernel.h>
   6#include <linux/delay.h>
   7#include <linux/init.h>
   8#include <linux/pci.h>
 
 
 
   9#include <linux/slab.h>
  10#include <linux/module.h>
  11#include <linux/cpumask.h>
  12#include <linux/pci-aspm.h>
  13#include <asm-generic/pci-bridge.h>
 
 
 
 
  14#include "pci.h"
  15
  16#define CARDBUS_LATENCY_TIMER	176	/* secondary latency timer */
  17#define CARDBUS_RESERVE_BUSNR	3
  18
  19static struct resource busn_resource = {
  20	.name	= "PCI busn",
  21	.start	= 0,
  22	.end	= 255,
  23	.flags	= IORESOURCE_BUS,
  24};
  25
  26/* Ugh.  Need to stop exporting this to modules. */
  27LIST_HEAD(pci_root_buses);
  28EXPORT_SYMBOL(pci_root_buses);
  29
  30static LIST_HEAD(pci_domain_busn_res_list);
  31
  32struct pci_domain_busn_res {
  33	struct list_head list;
  34	struct resource res;
  35	int domain_nr;
  36};
  37
  38static struct resource *get_pci_domain_busn_res(int domain_nr)
  39{
  40	struct pci_domain_busn_res *r;
  41
  42	list_for_each_entry(r, &pci_domain_busn_res_list, list)
  43		if (r->domain_nr == domain_nr)
  44			return &r->res;
  45
  46	r = kzalloc(sizeof(*r), GFP_KERNEL);
  47	if (!r)
  48		return NULL;
  49
  50	r->domain_nr = domain_nr;
  51	r->res.start = 0;
  52	r->res.end = 0xff;
  53	r->res.flags = IORESOURCE_BUS | IORESOURCE_PCI_FIXED;
  54
  55	list_add_tail(&r->list, &pci_domain_busn_res_list);
  56
  57	return &r->res;
  58}
  59
  60static int find_anything(struct device *dev, void *data)
  61{
  62	return 1;
  63}
  64
  65/*
  66 * Some device drivers need know if pci is initiated.
  67 * Basically, we think pci is not initiated when there
  68 * is no device to be found on the pci_bus_type.
  69 */
  70int no_pci_devices(void)
  71{
  72	struct device *dev;
  73	int no_devices;
  74
  75	dev = bus_find_device(&pci_bus_type, NULL, NULL, find_anything);
  76	no_devices = (dev == NULL);
  77	put_device(dev);
  78	return no_devices;
  79}
  80EXPORT_SYMBOL(no_pci_devices);
  81
  82/*
  83 * PCI Bus Class
  84 */
  85static void release_pcibus_dev(struct device *dev)
  86{
  87	struct pci_bus *pci_bus = to_pci_bus(dev);
  88
  89	if (pci_bus->bridge)
  90		put_device(pci_bus->bridge);
  91	pci_bus_remove_resources(pci_bus);
  92	pci_release_bus_of_node(pci_bus);
  93	kfree(pci_bus);
  94}
  95
  96static struct class pcibus_class = {
  97	.name		= "pci_bus",
  98	.dev_release	= &release_pcibus_dev,
  99	.dev_groups	= pcibus_groups,
 100};
 101
 102static int __init pcibus_class_init(void)
 103{
 104	return class_register(&pcibus_class);
 105}
 106postcore_initcall(pcibus_class_init);
 107
 108static u64 pci_size(u64 base, u64 maxbase, u64 mask)
 109{
 110	u64 size = mask & maxbase;	/* Find the significant bits */
 111	if (!size)
 112		return 0;
 113
 114	/* Get the lowest of them to find the decode size, and
 115	   from that the extent.  */
 116	size = (size & ~(size-1)) - 1;
 117
 118	/* base == maxbase can be valid only if the BAR has
 119	   already been programmed with all 1s.  */
 120	if (base == maxbase && ((base | size) & mask) != mask)
 
 
 
 
 121		return 0;
 122
 123	return size;
 124}
 125
 126static inline unsigned long decode_bar(struct pci_dev *dev, u32 bar)
 127{
 128	u32 mem_type;
 129	unsigned long flags;
 130
 131	if ((bar & PCI_BASE_ADDRESS_SPACE) == PCI_BASE_ADDRESS_SPACE_IO) {
 132		flags = bar & ~PCI_BASE_ADDRESS_IO_MASK;
 133		flags |= IORESOURCE_IO;
 134		return flags;
 135	}
 136
 137	flags = bar & ~PCI_BASE_ADDRESS_MEM_MASK;
 138	flags |= IORESOURCE_MEM;
 139	if (flags & PCI_BASE_ADDRESS_MEM_PREFETCH)
 140		flags |= IORESOURCE_PREFETCH;
 141
 142	mem_type = bar & PCI_BASE_ADDRESS_MEM_TYPE_MASK;
 143	switch (mem_type) {
 144	case PCI_BASE_ADDRESS_MEM_TYPE_32:
 145		break;
 146	case PCI_BASE_ADDRESS_MEM_TYPE_1M:
 147		/* 1M mem BAR treated as 32-bit BAR */
 148		break;
 149	case PCI_BASE_ADDRESS_MEM_TYPE_64:
 150		flags |= IORESOURCE_MEM_64;
 151		break;
 152	default:
 153		/* mem unknown type treated as 32-bit BAR */
 154		break;
 155	}
 156	return flags;
 157}
 158
 159#define PCI_COMMAND_DECODE_ENABLE	(PCI_COMMAND_MEMORY | PCI_COMMAND_IO)
 160
 161/**
 162 * pci_read_base - read a PCI BAR
 163 * @dev: the PCI device
 164 * @type: type of the BAR
 165 * @res: resource buffer to be filled in
 166 * @pos: BAR position in the config space
 167 *
 168 * Returns 1 if the BAR is 64-bit, or 0 if 32-bit.
 169 */
 170int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type,
 171			struct resource *res, unsigned int pos)
 172{
 173	u32 l, sz, mask;
 
 174	u16 orig_cmd;
 175	struct pci_bus_region region, inverted_region;
 176	bool bar_too_big = false, bar_disabled = false;
 177
 178	mask = type ? PCI_ROM_ADDRESS_MASK : ~0;
 179
 180	/* No printks while decoding is disabled! */
 181	if (!dev->mmio_always_on) {
 182		pci_read_config_word(dev, PCI_COMMAND, &orig_cmd);
 183		if (orig_cmd & PCI_COMMAND_DECODE_ENABLE) {
 184			pci_write_config_word(dev, PCI_COMMAND,
 185				orig_cmd & ~PCI_COMMAND_DECODE_ENABLE);
 186		}
 187	}
 188
 189	res->name = pci_name(dev);
 190
 191	pci_read_config_dword(dev, pos, &l);
 192	pci_write_config_dword(dev, pos, l | mask);
 193	pci_read_config_dword(dev, pos, &sz);
 194	pci_write_config_dword(dev, pos, l);
 195
 196	/*
 197	 * All bits set in sz means the device isn't working properly.
 198	 * If the BAR isn't implemented, all bits must be 0.  If it's a
 199	 * memory BAR or a ROM, bit 0 must be clear; if it's an io BAR, bit
 200	 * 1 must be clear.
 201	 */
 202	if (!sz || sz == 0xffffffff)
 203		goto fail;
 204
 205	/*
 206	 * I don't know how l can have all bits set.  Copied from old code.
 207	 * Maybe it fixes a bug on some ancient platform.
 208	 */
 209	if (l == 0xffffffff)
 210		l = 0;
 211
 212	if (type == pci_bar_unknown) {
 213		res->flags = decode_bar(dev, l);
 214		res->flags |= IORESOURCE_SIZEALIGN;
 215		if (res->flags & IORESOURCE_IO) {
 216			l &= PCI_BASE_ADDRESS_IO_MASK;
 217			mask = PCI_BASE_ADDRESS_IO_MASK & (u32) IO_SPACE_LIMIT;
 
 218		} else {
 219			l &= PCI_BASE_ADDRESS_MEM_MASK;
 220			mask = (u32)PCI_BASE_ADDRESS_MEM_MASK;
 
 221		}
 222	} else {
 223		res->flags |= (l & IORESOURCE_ROM_ENABLE);
 224		l &= PCI_ROM_ADDRESS_MASK;
 225		mask = (u32)PCI_ROM_ADDRESS_MASK;
 
 
 226	}
 227
 228	if (res->flags & IORESOURCE_MEM_64) {
 229		u64 l64 = l;
 230		u64 sz64 = sz;
 231		u64 mask64 = mask | (u64)~0 << 32;
 232
 233		pci_read_config_dword(dev, pos + 4, &l);
 234		pci_write_config_dword(dev, pos + 4, ~0);
 235		pci_read_config_dword(dev, pos + 4, &sz);
 236		pci_write_config_dword(dev, pos + 4, l);
 237
 238		l64 |= ((u64)l << 32);
 239		sz64 |= ((u64)sz << 32);
 
 
 
 
 
 240
 241		sz64 = pci_size(l64, sz64, mask64);
 
 242
 243		if (!sz64)
 244			goto fail;
 
 
 
 245
 246		if ((sizeof(resource_size_t) < 8) && (sz64 > 0x100000000ULL)) {
 247			bar_too_big = true;
 248			goto fail;
 
 
 
 
 
 
 249		}
 250
 251		if ((sizeof(resource_size_t) < 8) && l) {
 252			/* Address above 32-bit boundary; disable the BAR */
 253			pci_write_config_dword(dev, pos, 0);
 254			pci_write_config_dword(dev, pos + 4, 0);
 255			res->flags |= IORESOURCE_UNSET;
 256			region.start = 0;
 257			region.end = sz64;
 258			bar_disabled = true;
 259		} else {
 260			region.start = l64;
 261			region.end = l64 + sz64;
 262		}
 263	} else {
 264		sz = pci_size(l, sz, mask);
 265
 266		if (!sz)
 267			goto fail;
 268
 269		region.start = l;
 270		region.end = l + sz;
 271	}
 272
 273	pcibios_bus_to_resource(dev->bus, res, &region);
 274	pcibios_resource_to_bus(dev->bus, &inverted_region, res);
 275
 276	/*
 277	 * If "A" is a BAR value (a bus address), "bus_to_resource(A)" is
 278	 * the corresponding resource address (the physical address used by
 279	 * the CPU.  Converting that resource address back to a bus address
 280	 * should yield the original BAR value:
 281	 *
 282	 *     resource_to_bus(bus_to_resource(A)) == A
 283	 *
 284	 * If it doesn't, CPU accesses to "bus_to_resource(A)" will not
 285	 * be claimed by the device.
 286	 */
 287	if (inverted_region.start != region.start) {
 288		dev_info(&dev->dev, "reg 0x%x: initial BAR value %pa invalid; forcing reassignment\n",
 289			 pos, &region.start);
 290		res->flags |= IORESOURCE_UNSET;
 291		res->end -= res->start;
 292		res->start = 0;
 
 
 
 293	}
 294
 295	goto out;
 296
 297
 298fail:
 299	res->flags = 0;
 300out:
 301	if (!dev->mmio_always_on &&
 302	    (orig_cmd & PCI_COMMAND_DECODE_ENABLE))
 303		pci_write_config_word(dev, PCI_COMMAND, orig_cmd);
 304
 305	if (bar_too_big)
 306		dev_err(&dev->dev, "reg 0x%x: can't handle 64-bit BAR\n", pos);
 307	if (res->flags && !bar_disabled)
 308		dev_printk(KERN_DEBUG, &dev->dev, "reg 0x%x: %pR\n", pos, res);
 309
 310	return (res->flags & IORESOURCE_MEM_64) ? 1 : 0;
 311}
 312
 313static void pci_read_bases(struct pci_dev *dev, unsigned int howmany, int rom)
 314{
 315	unsigned int pos, reg;
 316
 
 
 
 
 
 
 
 317	for (pos = 0; pos < howmany; pos++) {
 318		struct resource *res = &dev->resource[pos];
 319		reg = PCI_BASE_ADDRESS_0 + (pos << 2);
 320		pos += __pci_read_base(dev, pci_bar_unknown, res, reg);
 321	}
 322
 323	if (rom) {
 324		struct resource *res = &dev->resource[PCI_ROM_RESOURCE];
 325		dev->rom_base_reg = rom;
 326		res->flags = IORESOURCE_MEM | IORESOURCE_PREFETCH |
 327				IORESOURCE_READONLY | IORESOURCE_CACHEABLE |
 328				IORESOURCE_SIZEALIGN;
 329		__pci_read_base(dev, pci_bar_mem32, res, rom);
 330	}
 331}
 332
 333static void pci_read_bridge_io(struct pci_bus *child)
 
 334{
 335	struct pci_dev *dev = child->self;
 336	u8 io_base_lo, io_limit_lo;
 337	unsigned long io_mask, io_granularity, base, limit;
 338	struct pci_bus_region region;
 339	struct resource *res;
 340
 341	io_mask = PCI_IO_RANGE_MASK;
 342	io_granularity = 0x1000;
 343	if (dev->io_window_1k) {
 344		/* Support 1K I/O space granularity */
 345		io_mask = PCI_IO_1K_RANGE_MASK;
 346		io_granularity = 0x400;
 347	}
 348
 349	res = child->resource[0];
 350	pci_read_config_byte(dev, PCI_IO_BASE, &io_base_lo);
 351	pci_read_config_byte(dev, PCI_IO_LIMIT, &io_limit_lo);
 352	base = (io_base_lo & io_mask) << 8;
 353	limit = (io_limit_lo & io_mask) << 8;
 354
 355	if ((io_base_lo & PCI_IO_RANGE_TYPE_MASK) == PCI_IO_RANGE_TYPE_32) {
 356		u16 io_base_hi, io_limit_hi;
 357
 358		pci_read_config_word(dev, PCI_IO_BASE_UPPER16, &io_base_hi);
 359		pci_read_config_word(dev, PCI_IO_LIMIT_UPPER16, &io_limit_hi);
 360		base |= ((unsigned long) io_base_hi << 16);
 361		limit |= ((unsigned long) io_limit_hi << 16);
 362	}
 363
 364	if (base <= limit) {
 365		res->flags = (io_base_lo & PCI_IO_RANGE_TYPE_MASK) | IORESOURCE_IO;
 366		region.start = base;
 367		region.end = limit + io_granularity - 1;
 368		pcibios_bus_to_resource(dev->bus, res, &region);
 369		dev_printk(KERN_DEBUG, &dev->dev, "  bridge window %pR\n", res);
 
 370	}
 371}
 372
 373static void pci_read_bridge_mmio(struct pci_bus *child)
 
 374{
 375	struct pci_dev *dev = child->self;
 376	u16 mem_base_lo, mem_limit_lo;
 377	unsigned long base, limit;
 378	struct pci_bus_region region;
 379	struct resource *res;
 380
 381	res = child->resource[1];
 382	pci_read_config_word(dev, PCI_MEMORY_BASE, &mem_base_lo);
 383	pci_read_config_word(dev, PCI_MEMORY_LIMIT, &mem_limit_lo);
 384	base = ((unsigned long) mem_base_lo & PCI_MEMORY_RANGE_MASK) << 16;
 385	limit = ((unsigned long) mem_limit_lo & PCI_MEMORY_RANGE_MASK) << 16;
 386	if (base <= limit) {
 387		res->flags = (mem_base_lo & PCI_MEMORY_RANGE_TYPE_MASK) | IORESOURCE_MEM;
 388		region.start = base;
 389		region.end = limit + 0xfffff;
 390		pcibios_bus_to_resource(dev->bus, res, &region);
 391		dev_printk(KERN_DEBUG, &dev->dev, "  bridge window %pR\n", res);
 
 392	}
 393}
 394
 395static void pci_read_bridge_mmio_pref(struct pci_bus *child)
 
 396{
 397	struct pci_dev *dev = child->self;
 398	u16 mem_base_lo, mem_limit_lo;
 399	unsigned long base, limit;
 
 400	struct pci_bus_region region;
 401	struct resource *res;
 402
 403	res = child->resource[2];
 404	pci_read_config_word(dev, PCI_PREF_MEMORY_BASE, &mem_base_lo);
 405	pci_read_config_word(dev, PCI_PREF_MEMORY_LIMIT, &mem_limit_lo);
 406	base = ((unsigned long) mem_base_lo & PCI_PREF_RANGE_MASK) << 16;
 407	limit = ((unsigned long) mem_limit_lo & PCI_PREF_RANGE_MASK) << 16;
 408
 409	if ((mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) == PCI_PREF_RANGE_TYPE_64) {
 410		u32 mem_base_hi, mem_limit_hi;
 411
 412		pci_read_config_dword(dev, PCI_PREF_BASE_UPPER32, &mem_base_hi);
 413		pci_read_config_dword(dev, PCI_PREF_LIMIT_UPPER32, &mem_limit_hi);
 414
 415		/*
 416		 * Some bridges set the base > limit by default, and some
 417		 * (broken) BIOSes do not initialize them.  If we find
 418		 * this, just assume they are not being used.
 419		 */
 420		if (mem_base_hi <= mem_limit_hi) {
 421#if BITS_PER_LONG == 64
 422			base |= ((unsigned long) mem_base_hi) << 32;
 423			limit |= ((unsigned long) mem_limit_hi) << 32;
 424#else
 425			if (mem_base_hi || mem_limit_hi) {
 426				dev_err(&dev->dev, "can't handle 64-bit "
 427					"address space for bridge\n");
 428				return;
 429			}
 430#endif
 431		}
 432	}
 
 
 
 
 
 
 
 
 
 
 433	if (base <= limit) {
 434		res->flags = (mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) |
 435					 IORESOURCE_MEM | IORESOURCE_PREFETCH;
 436		if (res->flags & PCI_PREF_RANGE_TYPE_64)
 437			res->flags |= IORESOURCE_MEM_64;
 438		region.start = base;
 439		region.end = limit + 0xfffff;
 440		pcibios_bus_to_resource(dev->bus, res, &region);
 441		dev_printk(KERN_DEBUG, &dev->dev, "  bridge window %pR\n", res);
 
 442	}
 443}
 444
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 445void pci_read_bridge_bases(struct pci_bus *child)
 446{
 447	struct pci_dev *dev = child->self;
 448	struct resource *res;
 449	int i;
 450
 451	if (pci_is_root_bus(child))	/* It's a host bus, nothing to read */
 452		return;
 453
 454	dev_info(&dev->dev, "PCI bridge to %pR%s\n",
 455		 &child->busn_res,
 456		 dev->transparent ? " (subtractive decode)" : "");
 457
 458	pci_bus_remove_resources(child);
 459	for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++)
 460		child->resource[i] = &dev->resource[PCI_BRIDGE_RESOURCES+i];
 461
 462	pci_read_bridge_io(child);
 463	pci_read_bridge_mmio(child);
 464	pci_read_bridge_mmio_pref(child);
 465
 466	if (dev->transparent) {
 467		pci_bus_for_each_resource(child->parent, res, i) {
 468			if (res) {
 469				pci_bus_add_resource(child, res,
 470						     PCI_SUBTRACTIVE_DECODE);
 471				dev_printk(KERN_DEBUG, &dev->dev,
 472					   "  bridge window %pR (subtractive decode)\n",
 473					   res);
 474			}
 475		}
 476	}
 477}
 478
 479static struct pci_bus *pci_alloc_bus(void)
 480{
 481	struct pci_bus *b;
 482
 483	b = kzalloc(sizeof(*b), GFP_KERNEL);
 484	if (!b)
 485		return NULL;
 486
 487	INIT_LIST_HEAD(&b->node);
 488	INIT_LIST_HEAD(&b->children);
 489	INIT_LIST_HEAD(&b->devices);
 490	INIT_LIST_HEAD(&b->slots);
 491	INIT_LIST_HEAD(&b->resources);
 492	b->max_bus_speed = PCI_SPEED_UNKNOWN;
 493	b->cur_bus_speed = PCI_SPEED_UNKNOWN;
 
 
 
 
 494	return b;
 495}
 496
 497static void pci_release_host_bridge_dev(struct device *dev)
 498{
 499	struct pci_host_bridge *bridge = to_pci_host_bridge(dev);
 500
 501	if (bridge->release_fn)
 502		bridge->release_fn(bridge);
 503
 504	pci_free_resource_list(&bridge->windows);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 505
 506	kfree(bridge);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 507}
 508
 509static struct pci_host_bridge *pci_alloc_host_bridge(struct pci_bus *b)
 
 510{
 
 511	struct pci_host_bridge *bridge;
 512
 513	bridge = kzalloc(sizeof(*bridge), GFP_KERNEL);
 514	if (!bridge)
 515		return NULL;
 516
 517	INIT_LIST_HEAD(&bridge->windows);
 518	bridge->bus = b;
 
 
 
 
 
 
 
 
 
 519	return bridge;
 520}
 
 
 
 
 
 
 
 521
 
 522static const unsigned char pcix_bus_speed[] = {
 523	PCI_SPEED_UNKNOWN,		/* 0 */
 524	PCI_SPEED_66MHz_PCIX,		/* 1 */
 525	PCI_SPEED_100MHz_PCIX,		/* 2 */
 526	PCI_SPEED_133MHz_PCIX,		/* 3 */
 527	PCI_SPEED_UNKNOWN,		/* 4 */
 528	PCI_SPEED_66MHz_PCIX_ECC,	/* 5 */
 529	PCI_SPEED_100MHz_PCIX_ECC,	/* 6 */
 530	PCI_SPEED_133MHz_PCIX_ECC,	/* 7 */
 531	PCI_SPEED_UNKNOWN,		/* 8 */
 532	PCI_SPEED_66MHz_PCIX_266,	/* 9 */
 533	PCI_SPEED_100MHz_PCIX_266,	/* A */
 534	PCI_SPEED_133MHz_PCIX_266,	/* B */
 535	PCI_SPEED_UNKNOWN,		/* C */
 536	PCI_SPEED_66MHz_PCIX_533,	/* D */
 537	PCI_SPEED_100MHz_PCIX_533,	/* E */
 538	PCI_SPEED_133MHz_PCIX_533	/* F */
 539};
 540
 
 541const unsigned char pcie_link_speed[] = {
 542	PCI_SPEED_UNKNOWN,		/* 0 */
 543	PCIE_SPEED_2_5GT,		/* 1 */
 544	PCIE_SPEED_5_0GT,		/* 2 */
 545	PCIE_SPEED_8_0GT,		/* 3 */
 546	PCI_SPEED_UNKNOWN,		/* 4 */
 547	PCI_SPEED_UNKNOWN,		/* 5 */
 548	PCI_SPEED_UNKNOWN,		/* 6 */
 549	PCI_SPEED_UNKNOWN,		/* 7 */
 550	PCI_SPEED_UNKNOWN,		/* 8 */
 551	PCI_SPEED_UNKNOWN,		/* 9 */
 552	PCI_SPEED_UNKNOWN,		/* A */
 553	PCI_SPEED_UNKNOWN,		/* B */
 554	PCI_SPEED_UNKNOWN,		/* C */
 555	PCI_SPEED_UNKNOWN,		/* D */
 556	PCI_SPEED_UNKNOWN,		/* E */
 557	PCI_SPEED_UNKNOWN		/* F */
 558};
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 559
 560void pcie_update_link_speed(struct pci_bus *bus, u16 linksta)
 561{
 562	bus->cur_bus_speed = pcie_link_speed[linksta & PCI_EXP_LNKSTA_CLS];
 563}
 564EXPORT_SYMBOL_GPL(pcie_update_link_speed);
 565
 566static unsigned char agp_speeds[] = {
 567	AGP_UNKNOWN,
 568	AGP_1X,
 569	AGP_2X,
 570	AGP_4X,
 571	AGP_8X
 572};
 573
 574static enum pci_bus_speed agp_speed(int agp3, int agpstat)
 575{
 576	int index = 0;
 577
 578	if (agpstat & 4)
 579		index = 3;
 580	else if (agpstat & 2)
 581		index = 2;
 582	else if (agpstat & 1)
 583		index = 1;
 584	else
 585		goto out;
 586
 587	if (agp3) {
 588		index += 2;
 589		if (index == 5)
 590			index = 0;
 591	}
 592
 593 out:
 594	return agp_speeds[index];
 595}
 596
 597
 598static void pci_set_bus_speed(struct pci_bus *bus)
 599{
 600	struct pci_dev *bridge = bus->self;
 601	int pos;
 602
 603	pos = pci_find_capability(bridge, PCI_CAP_ID_AGP);
 604	if (!pos)
 605		pos = pci_find_capability(bridge, PCI_CAP_ID_AGP3);
 606	if (pos) {
 607		u32 agpstat, agpcmd;
 608
 609		pci_read_config_dword(bridge, pos + PCI_AGP_STATUS, &agpstat);
 610		bus->max_bus_speed = agp_speed(agpstat & 8, agpstat & 7);
 611
 612		pci_read_config_dword(bridge, pos + PCI_AGP_COMMAND, &agpcmd);
 613		bus->cur_bus_speed = agp_speed(agpstat & 8, agpcmd & 7);
 614	}
 615
 616	pos = pci_find_capability(bridge, PCI_CAP_ID_PCIX);
 617	if (pos) {
 618		u16 status;
 619		enum pci_bus_speed max;
 620
 621		pci_read_config_word(bridge, pos + PCI_X_BRIDGE_SSTATUS,
 622				     &status);
 623
 624		if (status & PCI_X_SSTATUS_533MHZ) {
 625			max = PCI_SPEED_133MHz_PCIX_533;
 626		} else if (status & PCI_X_SSTATUS_266MHZ) {
 627			max = PCI_SPEED_133MHz_PCIX_266;
 628		} else if (status & PCI_X_SSTATUS_133MHZ) {
 629			if ((status & PCI_X_SSTATUS_VERS) == PCI_X_SSTATUS_V2) {
 630				max = PCI_SPEED_133MHz_PCIX_ECC;
 631			} else {
 632				max = PCI_SPEED_133MHz_PCIX;
 633			}
 634		} else {
 635			max = PCI_SPEED_66MHz_PCIX;
 636		}
 637
 638		bus->max_bus_speed = max;
 639		bus->cur_bus_speed = pcix_bus_speed[
 640			(status & PCI_X_SSTATUS_FREQ) >> 6];
 641
 642		return;
 643	}
 644
 645	if (pci_is_pcie(bridge)) {
 646		u32 linkcap;
 647		u16 linksta;
 648
 649		pcie_capability_read_dword(bridge, PCI_EXP_LNKCAP, &linkcap);
 650		bus->max_bus_speed = pcie_link_speed[linkcap & PCI_EXP_LNKCAP_SLS];
 651
 652		pcie_capability_read_word(bridge, PCI_EXP_LNKSTA, &linksta);
 653		pcie_update_link_speed(bus, linksta);
 654	}
 655}
 656
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 657
 658static struct pci_bus *pci_alloc_child_bus(struct pci_bus *parent,
 659					   struct pci_dev *bridge, int busnr)
 660{
 661	struct pci_bus *child;
 
 662	int i;
 663	int ret;
 664
 665	/*
 666	 * Allocate a new bus, and inherit stuff from the parent..
 667	 */
 668	child = pci_alloc_bus();
 669	if (!child)
 670		return NULL;
 671
 672	child->parent = parent;
 673	child->ops = parent->ops;
 674	child->msi = parent->msi;
 675	child->sysdata = parent->sysdata;
 676	child->bus_flags = parent->bus_flags;
 677
 678	/* initialize some portions of the bus device, but don't register it
 679	 * now as the parent is not properly set up yet.
 
 
 
 
 
 
 
 680	 */
 681	child->dev.class = &pcibus_class;
 682	dev_set_name(&child->dev, "%04x:%02x", pci_domain_nr(child), busnr);
 683
 684	/*
 685	 * Set up the primary, secondary and subordinate
 686	 * bus numbers.
 687	 */
 688	child->number = child->busn_res.start = busnr;
 689	child->primary = parent->busn_res.start;
 690	child->busn_res.end = 0xff;
 691
 692	if (!bridge) {
 693		child->dev.parent = parent->bridge;
 694		goto add_dev;
 695	}
 696
 697	child->self = bridge;
 698	child->bridge = get_device(&bridge->dev);
 699	child->dev.parent = child->bridge;
 700	pci_set_bus_of_node(child);
 701	pci_set_bus_speed(child);
 702
 703	/* Set up default resource pointers and names.. */
 
 
 
 
 
 
 
 
 
 
 704	for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++) {
 705		child->resource[i] = &bridge->resource[PCI_BRIDGE_RESOURCES+i];
 706		child->resource[i]->name = child->name;
 707	}
 708	bridge->subordinate = child;
 709
 710add_dev:
 
 711	ret = device_register(&child->dev);
 712	WARN_ON(ret < 0);
 713
 714	pcibios_add_bus(child);
 715
 
 
 
 
 
 
 716	/* Create legacy_io and legacy_mem files for this bus */
 717	pci_create_legacy_files(child);
 718
 719	return child;
 720}
 721
 722struct pci_bus *__ref pci_add_new_bus(struct pci_bus *parent, struct pci_dev *dev, int busnr)
 
 723{
 724	struct pci_bus *child;
 725
 726	child = pci_alloc_child_bus(parent, dev, busnr);
 727	if (child) {
 728		down_write(&pci_bus_sem);
 729		list_add_tail(&child->node, &parent->children);
 730		up_write(&pci_bus_sem);
 731	}
 732	return child;
 733}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 734
 735/*
 
 
 
 
 
 
 
 
 
 
 
 736 * If it's a bridge, configure it and scan the bus behind it.
 737 * For CardBus bridges, we don't scan behind as the devices will
 738 * be handled by the bridge driver itself.
 739 *
 740 * We need to process bridges in two passes -- first we scan those
 741 * already configured by the BIOS and after we are done with all of
 742 * them, we proceed to assigning numbers to the remaining buses in
 743 * order to avoid overlaps between old and new bus numbers.
 
 
 744 */
 745int pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass)
 
 
 746{
 747	struct pci_bus *child;
 748	int is_cardbus = (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS);
 749	u32 buses, i, j = 0;
 750	u16 bctl;
 751	u8 primary, secondary, subordinate;
 752	int broken = 0;
 
 
 
 
 
 
 
 
 
 753
 754	pci_read_config_dword(dev, PCI_PRIMARY_BUS, &buses);
 755	primary = buses & 0xFF;
 756	secondary = (buses >> 8) & 0xFF;
 757	subordinate = (buses >> 16) & 0xFF;
 758
 759	dev_dbg(&dev->dev, "scanning [bus %02x-%02x] behind bridge, pass %d\n",
 760		secondary, subordinate, pass);
 761
 762	if (!primary && (primary != bus->number) && secondary && subordinate) {
 763		dev_warn(&dev->dev, "Primary bus is hard wired to 0\n");
 764		primary = bus->number;
 765	}
 766
 767	/* Check if setup is sensible at all */
 768	if (!pass &&
 769	    (primary != bus->number || secondary <= bus->number ||
 770	     secondary > subordinate || subordinate > bus->busn_res.end)) {
 771		dev_info(&dev->dev, "bridge configuration invalid ([bus %02x-%02x]), reconfiguring\n",
 772			 secondary, subordinate);
 773		broken = 1;
 774	}
 775
 776	/* Disable MasterAbortMode during probing to avoid reporting
 777	   of bus errors (in some architectures) */
 
 
 778	pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &bctl);
 779	pci_write_config_word(dev, PCI_BRIDGE_CONTROL,
 780			      bctl & ~PCI_BRIDGE_CTL_MASTER_ABORT);
 781
 
 
 782	if ((secondary || subordinate) && !pcibios_assign_all_busses() &&
 783	    !is_cardbus && !broken) {
 784		unsigned int cmax;
 
 785		/*
 786		 * Bus already configured by firmware, process it in the first
 787		 * pass and just note the configuration.
 788		 */
 789		if (pass)
 790			goto out;
 791
 792		/*
 793		 * The bus might already exist for two reasons: Either we are
 794		 * rescanning the bus or the bus is reachable through more than
 795		 * one bridge. The second case can happen with the i450NX
 796		 * chipset.
 797		 */
 798		child = pci_find_bus(pci_domain_nr(bus), secondary);
 799		if (!child) {
 800			child = pci_add_new_bus(bus, dev, secondary);
 801			if (!child)
 802				goto out;
 803			child->primary = primary;
 804			pci_bus_insert_busn_res(child, secondary, subordinate);
 805			child->bridge_ctl = bctl;
 806		}
 807
 808		cmax = pci_scan_child_bus(child);
 
 809		if (cmax > subordinate)
 810			dev_warn(&dev->dev, "bridge has subordinate %02x but max busn %02x\n",
 811				 subordinate, cmax);
 812		/* subordinate should equal child->busn_res.end */
 
 813		if (subordinate > max)
 814			max = subordinate;
 815	} else {
 
 816		/*
 817		 * We need to assign a number to this bus which we always
 818		 * do in the second pass.
 819		 */
 820		if (!pass) {
 821			if (pcibios_assign_all_busses() || broken || is_cardbus)
 822				/* Temporarily disable forwarding of the
 823				   configuration cycles on all bridges in
 824				   this bus segment to avoid possible
 825				   conflicts in the second pass between two
 826				   bridges programmed with overlapping
 827				   bus ranges. */
 
 
 
 828				pci_write_config_dword(dev, PCI_PRIMARY_BUS,
 829						       buses & ~0xffffff);
 830			goto out;
 831		}
 832
 833		if (max >= bus->busn_res.end) {
 834			dev_warn(&dev->dev, "can't allocate child bus %02x from %pR\n",
 835				 max, &bus->busn_res);
 836			goto out;
 837		}
 838
 839		/* Clear errors */
 840		pci_write_config_word(dev, PCI_STATUS, 0xffff);
 841
 842		/* The bus will already exist if we are rescanning */
 843		child = pci_find_bus(pci_domain_nr(bus), max+1);
 
 
 
 
 
 
 
 
 
 
 
 844		if (!child) {
 845			child = pci_add_new_bus(bus, dev, max+1);
 846			if (!child)
 847				goto out;
 848			pci_bus_insert_busn_res(child, max+1,
 849						bus->busn_res.end);
 850		}
 851		max++;
 
 
 
 852		buses = (buses & 0xff000000)
 853		      | ((unsigned int)(child->primary)     <<  0)
 854		      | ((unsigned int)(child->busn_res.start)   <<  8)
 855		      | ((unsigned int)(child->busn_res.end) << 16);
 856
 857		/*
 858		 * yenta.c forces a secondary latency timer of 176.
 859		 * Copy that behaviour here.
 860		 */
 861		if (is_cardbus) {
 862			buses &= ~0xff000000;
 863			buses |= CARDBUS_LATENCY_TIMER << 24;
 864		}
 865
 866		/*
 867		 * We need to blast all three values with a single write.
 868		 */
 869		pci_write_config_dword(dev, PCI_PRIMARY_BUS, buses);
 870
 871		if (!is_cardbus) {
 872			child->bridge_ctl = bctl;
 873			max = pci_scan_child_bus(child);
 874		} else {
 
 875			/*
 876			 * For CardBus bridges, we leave 4 bus numbers
 877			 * as cards with a PCI-to-PCI bridge can be
 878			 * inserted later.
 879			 */
 880			for (i=0; i<CARDBUS_RESERVE_BUSNR; i++) {
 881				struct pci_bus *parent = bus;
 882				if (pci_find_bus(pci_domain_nr(bus),
 883							max+i+1))
 884					break;
 885				while (parent->parent) {
 886					if ((!pcibios_assign_all_busses()) &&
 887					    (parent->busn_res.end > max) &&
 888					    (parent->busn_res.end <= max+i)) {
 889						j = 1;
 890					}
 891					parent = parent->parent;
 892				}
 893				if (j) {
 
 894					/*
 895					 * Often, there are two cardbus bridges
 896					 * -- try to leave one valid bus number
 897					 * for each one.
 898					 */
 899					i /= 2;
 900					break;
 901				}
 902			}
 903			max += i;
 904		}
 
 905		/*
 906		 * Set the subordinate bus number to its real value.
 
 
 907		 */
 908		if (max > bus->busn_res.end) {
 909			dev_warn(&dev->dev, "max busn %02x is outside %pR\n",
 910				 max, &bus->busn_res);
 911			max = bus->busn_res.end;
 912		}
 913		pci_bus_update_busn_res_end(child, max);
 914		pci_write_config_byte(dev, PCI_SUBORDINATE_BUS, max);
 915	}
 916
 917	sprintf(child->name,
 918		(is_cardbus ? "PCI CardBus %04x:%02x" : "PCI Bus %04x:%02x"),
 919		pci_domain_nr(bus), child->number);
 920
 921	/* Has only triggered on CardBus, fixup is in yenta_socket */
 922	while (bus->parent) {
 923		if ((child->busn_res.end > bus->busn_res.end) ||
 924		    (child->number > bus->busn_res.end) ||
 925		    (child->number < bus->number) ||
 926		    (child->busn_res.end < bus->number)) {
 927			dev_info(&child->dev, "%pR %s "
 928				"hidden behind%s bridge %s %pR\n",
 929				&child->busn_res,
 930				(bus->number > child->busn_res.end &&
 931				 bus->busn_res.end < child->number) ?
 932					"wholly" : "partially",
 933				bus->self->transparent ? " transparent" : "",
 934				dev_name(&bus->dev),
 935				&bus->busn_res);
 936		}
 937		bus = bus->parent;
 938	}
 939
 940out:
 941	pci_write_config_word(dev, PCI_BRIDGE_CONTROL, bctl);
 942
 
 
 943	return max;
 944}
 945
 946/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 947 * Read interrupt line and base address registers.
 948 * The architecture-dependent code can tweak these, of course.
 949 */
 950static void pci_read_irq(struct pci_dev *dev)
 951{
 952	unsigned char irq;
 953
 
 
 
 
 
 
 
 954	pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &irq);
 955	dev->pin = irq;
 956	if (irq)
 957		pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &irq);
 958	dev->irq = irq;
 959}
 960
 961void set_pcie_port_type(struct pci_dev *pdev)
 962{
 963	int pos;
 964	u16 reg16;
 
 
 
 965
 966	pos = pci_find_capability(pdev, PCI_CAP_ID_EXP);
 967	if (!pos)
 968		return;
 
 969	pdev->pcie_cap = pos;
 970	pci_read_config_word(pdev, pos + PCI_EXP_FLAGS, &reg16);
 971	pdev->pcie_flags_reg = reg16;
 972	pci_read_config_word(pdev, pos + PCI_EXP_DEVCAP, &reg16);
 973	pdev->pcie_mpss = reg16 & PCI_EXP_DEVCAP_PAYLOAD;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 974}
 975
 976void set_pcie_hotplug_bridge(struct pci_dev *pdev)
 977{
 978	u32 reg32;
 979
 980	pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP, &reg32);
 981	if (reg32 & PCI_EXP_SLTCAP_HPC)
 982		pdev->is_hotplug_bridge = 1;
 983}
 984
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 985
 986/**
 987 * pci_cfg_space_size - get the configuration space size of the PCI device.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 988 * @dev: PCI device
 989 *
 990 * Regular PCI devices have 256 bytes, but PCI-X 2 and PCI Express devices
 991 * have 4096 bytes.  Even if the device is capable, that doesn't mean we can
 992 * access it.  Maybe we don't have a way to generate extended config space
 993 * accesses, or the device is behind a reverse Express bridge.  So we try
 994 * reading the dword at 0x100 which must either be 0 or a valid extended
 995 * capability header.
 996 */
 997static int pci_cfg_space_size_ext(struct pci_dev *dev)
 998{
 999	u32 status;
1000	int pos = PCI_CFG_SPACE_SIZE;
1001
1002	if (pci_read_config_dword(dev, pos, &status) != PCIBIOS_SUCCESSFUL)
1003		goto fail;
1004	if (status == 0xffffffff)
1005		goto fail;
1006
1007	return PCI_CFG_SPACE_EXP_SIZE;
1008
1009 fail:
1010	return PCI_CFG_SPACE_SIZE;
1011}
1012
1013int pci_cfg_space_size(struct pci_dev *dev)
1014{
1015	int pos;
1016	u32 status;
1017	u16 class;
1018
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1019	class = dev->class >> 8;
1020	if (class == PCI_CLASS_BRIDGE_HOST)
1021		return pci_cfg_space_size_ext(dev);
1022
1023	if (!pci_is_pcie(dev)) {
1024		pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1025		if (!pos)
1026			goto fail;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1027
1028		pci_read_config_dword(dev, pos + PCI_X_STATUS, &status);
1029		if (!(status & (PCI_X_STATUS_266MHZ | PCI_X_STATUS_533MHZ)))
1030			goto fail;
 
 
 
 
1031	}
 
 
 
 
1032
1033	return pci_cfg_space_size_ext(dev);
 
 
1034
1035 fail:
1036	return PCI_CFG_SPACE_SIZE;
 
 
 
 
1037}
1038
1039#define LEGACY_IO_RESOURCE	(IORESOURCE_IO | IORESOURCE_PCI_FIXED)
1040
1041/**
1042 * pci_setup_device - fill in class and map information of a device
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1043 * @dev: the device structure to fill
1044 *
1045 * Initialize the device structure with information about the device's
1046 * vendor,class,memory and IO-space addresses,IRQ lines etc.
1047 * Called at initialisation of the PCI subsystem and by CardBus services.
1048 * Returns 0 on success and negative if unknown type of device (not normal,
1049 * bridge or CardBus).
1050 */
1051int pci_setup_device(struct pci_dev *dev)
1052{
1053	u32 class;
 
1054	u8 hdr_type;
1055	struct pci_slot *slot;
1056	int pos = 0;
1057	struct pci_bus_region region;
1058	struct resource *res;
1059
1060	if (pci_read_config_byte(dev, PCI_HEADER_TYPE, &hdr_type))
1061		return -EIO;
1062
1063	dev->sysdata = dev->bus->sysdata;
1064	dev->dev.parent = dev->bus->bridge;
1065	dev->dev.bus = &pci_bus_type;
1066	dev->hdr_type = hdr_type & 0x7f;
1067	dev->multifunction = !!(hdr_type & 0x80);
1068	dev->error_state = pci_channel_io_normal;
1069	set_pcie_port_type(dev);
1070
1071	list_for_each_entry(slot, &dev->bus->slots, list)
1072		if (PCI_SLOT(dev->devfn) == slot->number)
1073			dev->slot = slot;
 
 
 
1074
1075	/* Assume 32-bit PCI; let 64-bit PCI cards (which are far rarer)
1076	   set this higher, assuming the system even supports it.  */
 
 
1077	dev->dma_mask = 0xffffffff;
1078
1079	dev_set_name(&dev->dev, "%04x:%02x:%02x.%d", pci_domain_nr(dev->bus),
1080		     dev->bus->number, PCI_SLOT(dev->devfn),
1081		     PCI_FUNC(dev->devfn));
1082
1083	pci_read_config_dword(dev, PCI_CLASS_REVISION, &class);
 
1084	dev->revision = class & 0xff;
1085	dev->class = class >> 8;		    /* upper 3 bytes */
1086
1087	dev_printk(KERN_DEBUG, &dev->dev, "[%04x:%04x] type %02x class %#08x\n",
1088		   dev->vendor, dev->device, dev->hdr_type, dev->class);
1089
1090	/* need to have dev->class ready */
1091	dev->cfg_size = pci_cfg_space_size(dev);
1092
 
 
 
 
 
1093	/* "Unknown power state" */
1094	dev->current_state = PCI_UNKNOWN;
1095
1096	/* Early fixups, before probing the BARs */
1097	pci_fixup_device(pci_fixup_early, dev);
1098	/* device class may be changed after fixup */
 
 
 
 
 
 
 
1099	class = dev->class >> 8;
1100
 
 
 
 
 
 
 
 
 
 
 
 
1101	switch (dev->hdr_type) {		    /* header type */
1102	case PCI_HEADER_TYPE_NORMAL:		    /* standard header */
1103		if (class == PCI_CLASS_BRIDGE_PCI)
1104			goto bad;
1105		pci_read_irq(dev);
1106		pci_read_bases(dev, 6, PCI_ROM_ADDRESS);
1107		pci_read_config_word(dev, PCI_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor);
1108		pci_read_config_word(dev, PCI_SUBSYSTEM_ID, &dev->subsystem_device);
1109
1110		/*
1111		 * Do the ugly legacy mode stuff here rather than broken chip
1112		 * quirk code. Legacy mode ATA controllers have fixed
1113		 * addresses. These are not always echoed in BAR0-3, and
1114		 * BAR0-3 in a few cases contain junk!
1115		 */
1116		if (class == PCI_CLASS_STORAGE_IDE) {
1117			u8 progif;
1118			pci_read_config_byte(dev, PCI_CLASS_PROG, &progif);
1119			if ((progif & 1) == 0) {
1120				region.start = 0x1F0;
1121				region.end = 0x1F7;
1122				res = &dev->resource[0];
1123				res->flags = LEGACY_IO_RESOURCE;
1124				pcibios_bus_to_resource(dev->bus, res, &region);
1125				dev_info(&dev->dev, "legacy IDE quirk: reg 0x10: %pR\n",
1126					 res);
1127				region.start = 0x3F6;
1128				region.end = 0x3F6;
1129				res = &dev->resource[1];
1130				res->flags = LEGACY_IO_RESOURCE;
1131				pcibios_bus_to_resource(dev->bus, res, &region);
1132				dev_info(&dev->dev, "legacy IDE quirk: reg 0x14: %pR\n",
1133					 res);
1134			}
1135			if ((progif & 4) == 0) {
1136				region.start = 0x170;
1137				region.end = 0x177;
1138				res = &dev->resource[2];
1139				res->flags = LEGACY_IO_RESOURCE;
1140				pcibios_bus_to_resource(dev->bus, res, &region);
1141				dev_info(&dev->dev, "legacy IDE quirk: reg 0x18: %pR\n",
1142					 res);
1143				region.start = 0x376;
1144				region.end = 0x376;
1145				res = &dev->resource[3];
1146				res->flags = LEGACY_IO_RESOURCE;
1147				pcibios_bus_to_resource(dev->bus, res, &region);
1148				dev_info(&dev->dev, "legacy IDE quirk: reg 0x1c: %pR\n",
1149					 res);
1150			}
1151		}
1152		break;
1153
1154	case PCI_HEADER_TYPE_BRIDGE:		    /* bridge header */
1155		if (class != PCI_CLASS_BRIDGE_PCI)
1156			goto bad;
1157		/* The PCI-to-PCI bridge spec requires that subtractive
1158		   decoding (i.e. transparent) bridge must have programming
1159		   interface code of 0x01. */
1160		pci_read_irq(dev);
1161		dev->transparent = ((dev->class & 0xff) == 1);
1162		pci_read_bases(dev, 2, PCI_ROM_ADDRESS1);
 
1163		set_pcie_hotplug_bridge(dev);
1164		pos = pci_find_capability(dev, PCI_CAP_ID_SSVID);
1165		if (pos) {
1166			pci_read_config_word(dev, pos + PCI_SSVID_VENDOR_ID, &dev->subsystem_vendor);
1167			pci_read_config_word(dev, pos + PCI_SSVID_DEVICE_ID, &dev->subsystem_device);
1168		}
1169		break;
1170
1171	case PCI_HEADER_TYPE_CARDBUS:		    /* CardBus bridge header */
1172		if (class != PCI_CLASS_BRIDGE_CARDBUS)
1173			goto bad;
1174		pci_read_irq(dev);
1175		pci_read_bases(dev, 1, 0);
1176		pci_read_config_word(dev, PCI_CB_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor);
1177		pci_read_config_word(dev, PCI_CB_SUBSYSTEM_ID, &dev->subsystem_device);
1178		break;
1179
1180	default:				    /* unknown header */
1181		dev_err(&dev->dev, "unknown header type %02x, "
1182			"ignoring device\n", dev->hdr_type);
 
1183		return -EIO;
1184
1185	bad:
1186		dev_err(&dev->dev, "ignoring class %#08x (doesn't match header "
1187			"type %02x)\n", dev->class, dev->hdr_type);
1188		dev->class = PCI_CLASS_NOT_DEFINED;
1189	}
1190
1191	/* We found a fine healthy device, go go go... */
1192	return 0;
1193}
1194
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1195static void pci_release_capabilities(struct pci_dev *dev)
1196{
1197	pci_vpd_release(dev);
 
1198	pci_iov_release(dev);
1199	pci_free_cap_save_buffers(dev);
1200}
1201
1202/**
1203 * pci_release_dev - free a pci device structure when all users of it are finished.
 
1204 * @dev: device that's been disconnected
1205 *
1206 * Will be called only by the device core when all users of this pci device are
1207 * done.
1208 */
1209static void pci_release_dev(struct device *dev)
1210{
1211	struct pci_dev *pci_dev;
1212
1213	pci_dev = to_pci_dev(dev);
1214	pci_release_capabilities(pci_dev);
1215	pci_release_of_node(pci_dev);
1216	pcibios_release_device(pci_dev);
1217	pci_bus_put(pci_dev->bus);
 
 
 
1218	kfree(pci_dev);
1219}
1220
1221struct pci_dev *pci_alloc_dev(struct pci_bus *bus)
1222{
1223	struct pci_dev *dev;
1224
1225	dev = kzalloc(sizeof(struct pci_dev), GFP_KERNEL);
1226	if (!dev)
1227		return NULL;
1228
1229	INIT_LIST_HEAD(&dev->bus_list);
1230	dev->dev.type = &pci_dev_type;
1231	dev->bus = pci_bus_get(bus);
1232
 
 
 
 
 
 
 
 
 
1233	return dev;
1234}
1235EXPORT_SYMBOL(pci_alloc_dev);
1236
1237bool pci_bus_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l,
1238				 int crs_timeout)
 
 
 
 
 
1239{
1240	int delay = 1;
1241
1242	if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
1243		return false;
 
 
 
1244
1245	/* some broken boards return 0 or ~0 if a slot is empty: */
1246	if (*l == 0xffffffff || *l == 0x00000000 ||
1247	    *l == 0x0000ffff || *l == 0xffff0000)
1248		return false;
 
 
 
 
 
 
1249
1250	/* Configuration request Retry Status */
1251	while (*l == 0xffff0001) {
1252		if (!crs_timeout)
1253			return false;
 
 
 
 
 
1254
1255		msleep(delay);
1256		delay *= 2;
 
1257		if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
1258			return false;
1259		/* Card hasn't responded in 60 seconds?  Must be stuck. */
1260		if (delay > crs_timeout) {
1261			printk(KERN_WARNING "pci %04x:%02x:%02x.%d: not "
1262					"responding\n", pci_domain_nr(bus),
1263					bus->number, PCI_SLOT(devfn),
1264					PCI_FUNC(devfn));
1265			return false;
1266		}
1267	}
1268
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1269	return true;
1270}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1271EXPORT_SYMBOL(pci_bus_read_dev_vendor_id);
1272
1273/*
1274 * Read the config data for a PCI device, sanity-check it
1275 * and fill in the dev structure...
1276 */
1277static struct pci_dev *pci_scan_device(struct pci_bus *bus, int devfn)
1278{
1279	struct pci_dev *dev;
1280	u32 l;
1281
1282	if (!pci_bus_read_dev_vendor_id(bus, devfn, &l, 60*1000))
1283		return NULL;
1284
1285	dev = pci_alloc_dev(bus);
1286	if (!dev)
1287		return NULL;
1288
1289	dev->devfn = devfn;
1290	dev->vendor = l & 0xffff;
1291	dev->device = (l >> 16) & 0xffff;
1292
1293	pci_set_of_node(dev);
1294
1295	if (pci_setup_device(dev)) {
1296		pci_bus_put(dev->bus);
1297		kfree(dev);
1298		return NULL;
1299	}
1300
1301	return dev;
1302}
1303
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1304static void pci_init_capabilities(struct pci_dev *dev)
1305{
1306	/* MSI/MSI-X list */
1307	pci_msi_init_pci_dev(dev);
 
1308
1309	/* Buffers for saving PCIe and PCI-X capabilities */
1310	pci_allocate_cap_save_buffers(dev);
1311
1312	/* Power Management */
1313	pci_pm_init(dev);
 
 
 
 
 
 
 
 
 
 
 
1314
1315	/* Vital Product Data */
1316	pci_vpd_pci22_init(dev);
 
1317
1318	/* Alternative Routing-ID Forwarding */
1319	pci_configure_ari(dev);
 
 
 
 
 
 
1320
1321	/* Single Root I/O Virtualization */
1322	pci_iov_init(dev);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1323
1324	/* Enable ACS P2P upstream forwarding */
1325	pci_enable_acs(dev);
1326}
1327
1328void pci_device_add(struct pci_dev *dev, struct pci_bus *bus)
1329{
1330	int ret;
1331
 
 
1332	device_initialize(&dev->dev);
1333	dev->dev.release = pci_release_dev;
1334
1335	set_dev_node(&dev->dev, pcibus_to_node(bus));
1336	dev->dev.dma_mask = &dev->dma_mask;
1337	dev->dev.dma_parms = &dev->dma_parms;
1338	dev->dev.coherent_dma_mask = 0xffffffffull;
1339
1340	pci_set_dma_max_seg_size(dev, 65536);
1341	pci_set_dma_seg_boundary(dev, 0xffffffff);
 
 
1342
1343	/* Fix up broken headers */
1344	pci_fixup_device(pci_fixup_header, dev);
1345
1346	/* moved out from quirk header fixup code */
1347	pci_reassigndev_resource_alignment(dev);
1348
1349	/* Clear the state_saved flag. */
1350	dev->state_saved = false;
1351
1352	/* Initialize various capabilities */
1353	pci_init_capabilities(dev);
1354
1355	/*
1356	 * Add the device to our list of discovered devices
1357	 * and the bus list for fixup functions, etc.
1358	 */
1359	down_write(&pci_bus_sem);
1360	list_add_tail(&dev->bus_list, &bus->devices);
1361	up_write(&pci_bus_sem);
1362
1363	ret = pcibios_add_device(dev);
1364	WARN_ON(ret < 0);
1365
 
 
 
1366	/* Notifier could use PCI capabilities */
1367	dev->match_driver = false;
1368	ret = device_add(&dev->dev);
1369	WARN_ON(ret < 0);
1370}
1371
1372struct pci_dev *__ref pci_scan_single_device(struct pci_bus *bus, int devfn)
1373{
1374	struct pci_dev *dev;
1375
1376	dev = pci_get_slot(bus, devfn);
1377	if (dev) {
1378		pci_dev_put(dev);
1379		return dev;
1380	}
1381
1382	dev = pci_scan_device(bus, devfn);
1383	if (!dev)
1384		return NULL;
1385
1386	pci_device_add(dev, bus);
1387
1388	return dev;
1389}
1390EXPORT_SYMBOL(pci_scan_single_device);
1391
1392static unsigned next_fn(struct pci_bus *bus, struct pci_dev *dev, unsigned fn)
1393{
1394	int pos;
1395	u16 cap = 0;
1396	unsigned next_fn;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1397
1398	if (pci_ari_enabled(bus)) {
1399		if (!dev)
1400			return 0;
1401		pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI);
1402		if (!pos)
1403			return 0;
1404
1405		pci_read_config_word(dev, pos + PCI_ARI_CAP, &cap);
1406		next_fn = PCI_ARI_CAP_NFN(cap);
1407		if (next_fn <= fn)
1408			return 0;	/* protect against malformed list */
1409
1410		return next_fn;
1411	}
1412
1413	/* dev may be NULL for non-contiguous multifunction devices */
1414	if (!dev || dev->multifunction)
1415		return (fn + 1) % 8;
1416
1417	return 0;
1418}
1419
1420static int only_one_child(struct pci_bus *bus)
1421{
1422	struct pci_dev *parent = bus->self;
1423
1424	if (!parent || !pci_is_pcie(parent))
 
 
 
 
1425		return 0;
1426	if (pci_pcie_type(parent) == PCI_EXP_TYPE_ROOT_PORT)
1427		return 1;
1428	if (pci_pcie_type(parent) == PCI_EXP_TYPE_DOWNSTREAM &&
1429	    !pci_has_flag(PCI_SCAN_ALL_PCIE_DEVS))
 
 
 
1430		return 1;
 
1431	return 0;
1432}
1433
1434/**
1435 * pci_scan_slot - scan a PCI slot on a bus for devices.
1436 * @bus: PCI bus to scan
1437 * @devfn: slot number to scan (must have zero function.)
1438 *
1439 * Scan a PCI slot on the specified PCI bus for devices, adding
1440 * discovered devices to the @bus->devices list.  New devices
1441 * will not have is_added set.
1442 *
1443 * Returns the number of new devices found.
1444 */
1445int pci_scan_slot(struct pci_bus *bus, int devfn)
1446{
1447	unsigned fn, nr = 0;
1448	struct pci_dev *dev;
 
1449
1450	if (only_one_child(bus) && (devfn > 0))
1451		return 0; /* Already scanned the entire slot */
1452
1453	dev = pci_scan_single_device(bus, devfn);
1454	if (!dev)
1455		return 0;
1456	if (!dev->is_added)
1457		nr++;
1458
1459	for (fn = next_fn(bus, dev, 0); fn > 0; fn = next_fn(bus, dev, fn)) {
1460		dev = pci_scan_single_device(bus, devfn + fn);
1461		if (dev) {
1462			if (!dev->is_added)
1463				nr++;
1464			dev->multifunction = 1;
 
 
 
 
 
 
 
 
 
1465		}
1466	}
 
1467
1468	/* only one slot has pcie device */
1469	if (bus->self && nr)
1470		pcie_aspm_init_link_state(bus->self);
1471
1472	return nr;
1473}
 
1474
1475static int pcie_find_smpss(struct pci_dev *dev, void *data)
1476{
1477	u8 *smpss = data;
1478
1479	if (!pci_is_pcie(dev))
1480		return 0;
1481
1482	/*
1483	 * We don't have a way to change MPS settings on devices that have
1484	 * drivers attached.  A hot-added device might support only the minimum
1485	 * MPS setting (MPS=128).  Therefore, if the fabric contains a bridge
1486	 * where devices may be hot-added, we limit the fabric MPS to 128 so
1487	 * hot-added devices will work correctly.
1488	 *
1489	 * However, if we hot-add a device to a slot directly below a Root
1490	 * Port, it's impossible for there to be other existing devices below
1491	 * the port.  We don't limit the MPS in this case because we can
1492	 * reconfigure MPS on both the Root Port and the hot-added device,
1493	 * and there are no other devices involved.
1494	 *
1495	 * Note that this PCIE_BUS_SAFE path assumes no peer-to-peer DMA.
1496	 */
1497	if (dev->is_hotplug_bridge &&
1498	    pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT)
1499		*smpss = 0;
1500
1501	if (*smpss > dev->pcie_mpss)
1502		*smpss = dev->pcie_mpss;
1503
1504	return 0;
1505}
1506
1507static void pcie_write_mps(struct pci_dev *dev, int mps)
1508{
1509	int rc;
1510
1511	if (pcie_bus_config == PCIE_BUS_PERFORMANCE) {
1512		mps = 128 << dev->pcie_mpss;
1513
1514		if (pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT &&
1515		    dev->bus->self)
1516			/* For "Performance", the assumption is made that
 
 
1517			 * downstream communication will never be larger than
1518			 * the MRRS.  So, the MPS only needs to be configured
1519			 * for the upstream communication.  This being the case,
1520			 * walk from the top down and set the MPS of the child
1521			 * to that of the parent bus.
1522			 *
1523			 * Configure the device MPS with the smaller of the
1524			 * device MPSS or the bridge MPS (which is assumed to be
1525			 * properly configured at this point to the largest
1526			 * allowable MPS based on its parent bus).
1527			 */
1528			mps = min(mps, pcie_get_mps(dev->bus->self));
1529	}
1530
1531	rc = pcie_set_mps(dev, mps);
1532	if (rc)
1533		dev_err(&dev->dev, "Failed attempting to set the MPS\n");
1534}
1535
1536static void pcie_write_mrrs(struct pci_dev *dev)
1537{
1538	int rc, mrrs;
1539
1540	/* In the "safe" case, do not configure the MRRS.  There appear to be
 
1541	 * issues with setting MRRS to 0 on a number of devices.
1542	 */
1543	if (pcie_bus_config != PCIE_BUS_PERFORMANCE)
1544		return;
1545
1546	/* For Max performance, the MRRS must be set to the largest supported
 
1547	 * value.  However, it cannot be configured larger than the MPS the
1548	 * device or the bus can support.  This should already be properly
1549	 * configured by a prior call to pcie_write_mps.
1550	 */
1551	mrrs = pcie_get_mps(dev);
1552
1553	/* MRRS is a R/W register.  Invalid values can be written, but a
 
1554	 * subsequent read will verify if the value is acceptable or not.
1555	 * If the MRRS value provided is not acceptable (e.g., too large),
1556	 * shrink the value until it is acceptable to the HW.
1557	 */
1558	while (mrrs != pcie_get_readrq(dev) && mrrs >= 128) {
1559		rc = pcie_set_readrq(dev, mrrs);
1560		if (!rc)
1561			break;
1562
1563		dev_warn(&dev->dev, "Failed attempting to set the MRRS\n");
1564		mrrs /= 2;
1565	}
1566
1567	if (mrrs < 128)
1568		dev_err(&dev->dev, "MRRS was unable to be configured with a "
1569			"safe value.  If problems are experienced, try running "
1570			"with pci=pcie_bus_safe.\n");
1571}
1572
1573static void pcie_bus_detect_mps(struct pci_dev *dev)
1574{
1575	struct pci_dev *bridge = dev->bus->self;
1576	int mps, p_mps;
1577
1578	if (!bridge)
1579		return;
1580
1581	mps = pcie_get_mps(dev);
1582	p_mps = pcie_get_mps(bridge);
1583
1584	if (mps != p_mps)
1585		dev_warn(&dev->dev, "Max Payload Size %d, but upstream %s set to %d; if necessary, use \"pci=pcie_bus_safe\" and report a bug\n",
1586			 mps, pci_name(bridge), p_mps);
1587}
1588
1589static int pcie_bus_configure_set(struct pci_dev *dev, void *data)
1590{
1591	int mps, orig_mps;
1592
1593	if (!pci_is_pcie(dev))
1594		return 0;
1595
1596	if (pcie_bus_config == PCIE_BUS_TUNE_OFF) {
1597		pcie_bus_detect_mps(dev);
1598		return 0;
1599	}
1600
1601	mps = 128 << *(u8 *)data;
1602	orig_mps = pcie_get_mps(dev);
1603
1604	pcie_write_mps(dev, mps);
1605	pcie_write_mrrs(dev);
1606
1607	dev_info(&dev->dev, "Max Payload Size set to %4d/%4d (was %4d), "
1608		 "Max Read Rq %4d\n", pcie_get_mps(dev), 128 << dev->pcie_mpss,
1609		 orig_mps, pcie_get_readrq(dev));
1610
1611	return 0;
1612}
1613
1614/* pcie_bus_configure_settings requires that pci_walk_bus work in a top-down,
 
1615 * parents then children fashion.  If this changes, then this code will not
1616 * work as designed.
1617 */
1618void pcie_bus_configure_settings(struct pci_bus *bus)
1619{
1620	u8 smpss;
1621
1622	if (!bus->self)
1623		return;
1624
1625	if (!pci_is_pcie(bus->self))
1626		return;
1627
1628	/* FIXME - Peer to peer DMA is possible, though the endpoint would need
 
1629	 * to be aware of the MPS of the destination.  To work around this,
1630	 * simply force the MPS of the entire system to the smallest possible.
1631	 */
1632	if (pcie_bus_config == PCIE_BUS_PEER2PEER)
1633		smpss = 0;
1634
1635	if (pcie_bus_config == PCIE_BUS_SAFE) {
1636		smpss = bus->self->pcie_mpss;
1637
1638		pcie_find_smpss(bus->self, &smpss);
1639		pci_walk_bus(bus, pcie_find_smpss, &smpss);
1640	}
1641
1642	pcie_bus_configure_set(bus->self, &smpss);
1643	pci_walk_bus(bus, pcie_bus_configure_set, &smpss);
1644}
1645EXPORT_SYMBOL_GPL(pcie_bus_configure_settings);
1646
1647unsigned int pci_scan_child_bus(struct pci_bus *bus)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1648{
1649	unsigned int devfn, pass, max = bus->busn_res.start;
 
 
1650	struct pci_dev *dev;
1651
1652	dev_dbg(&bus->dev, "scanning bus\n");
1653
1654	/* Go find them, Rover! */
1655	for (devfn = 0; devfn < 0x100; devfn += 8)
1656		pci_scan_slot(bus, devfn);
1657
1658	/* Reserve buses for SR-IOV capability. */
1659	max += pci_iov_bus_range(bus);
 
1660
1661	/*
1662	 * After performing arch-dependent fixup of the bus, look behind
1663	 * all PCI-to-PCI bridges on this bus.
1664	 */
1665	if (!bus->is_added) {
1666		dev_dbg(&bus->dev, "fixups for bus\n");
1667		pcibios_fixup_bus(bus);
1668		bus->is_added = 1;
1669	}
1670
1671	for (pass=0; pass < 2; pass++)
1672		list_for_each_entry(dev, &bus->devices, bus_list) {
1673			if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
1674			    dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
1675				max = pci_scan_bridge(bus, dev, max, pass);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1676		}
1677
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1678	/*
1679	 * We've scanned the bus and so we know all about what's on
1680	 * the other side of any bridges that may be on this bus plus
1681	 * any devices.
1682	 *
1683	 * Return how far we've got finding sub-buses.
1684	 */
1685	dev_dbg(&bus->dev, "bus scan returning with max=%02x\n", max);
1686	return max;
1687}
1688
1689/**
1690 * pcibios_root_bridge_prepare - Platform-specific host bridge setup.
1691 * @bridge: Host bridge to set up.
 
 
 
 
 
 
 
 
 
 
 
 
 
1692 *
1693 * Default empty implementation.  Replace with an architecture-specific setup
1694 * routine, if necessary.
1695 */
1696int __weak pcibios_root_bridge_prepare(struct pci_host_bridge *bridge)
1697{
1698	return 0;
1699}
1700
1701void __weak pcibios_add_bus(struct pci_bus *bus)
1702{
1703}
1704
1705void __weak pcibios_remove_bus(struct pci_bus *bus)
1706{
1707}
1708
1709struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
1710		struct pci_ops *ops, void *sysdata, struct list_head *resources)
1711{
1712	int error;
1713	struct pci_host_bridge *bridge;
1714	struct pci_bus *b, *b2;
1715	struct pci_host_bridge_window *window, *n;
1716	struct resource *res;
1717	resource_size_t offset;
1718	char bus_addr[64];
1719	char *fmt;
1720
1721	b = pci_alloc_bus();
1722	if (!b)
1723		return NULL;
1724
1725	b->sysdata = sysdata;
1726	b->ops = ops;
1727	b->number = b->busn_res.start = bus;
1728	b2 = pci_find_bus(pci_domain_nr(b), bus);
1729	if (b2) {
1730		/* If we already got to this bus through a different bridge, ignore it */
1731		dev_dbg(&b2->dev, "bus already known\n");
1732		goto err_out;
1733	}
1734
1735	bridge = pci_alloc_host_bridge(b);
1736	if (!bridge)
1737		goto err_out;
 
1738
1739	bridge->dev.parent = parent;
1740	bridge->dev.release = pci_release_host_bridge_dev;
1741	dev_set_name(&bridge->dev, "pci%04x:%02x", pci_domain_nr(b), bus);
1742	error = pcibios_root_bridge_prepare(bridge);
1743	if (error) {
1744		kfree(bridge);
1745		goto err_out;
1746	}
1747
1748	error = device_register(&bridge->dev);
1749	if (error) {
1750		put_device(&bridge->dev);
1751		goto err_out;
1752	}
1753	b->bridge = get_device(&bridge->dev);
1754	device_enable_async_suspend(b->bridge);
1755	pci_set_bus_of_node(b);
1756
1757	if (!parent)
1758		set_dev_node(b->bridge, pcibus_to_node(b));
 
 
 
1759
1760	b->dev.class = &pcibus_class;
1761	b->dev.parent = b->bridge;
1762	dev_set_name(&b->dev, "%04x:%02x", pci_domain_nr(b), bus);
1763	error = device_register(&b->dev);
1764	if (error)
1765		goto class_dev_reg_err;
1766
1767	pcibios_add_bus(b);
 
 
 
 
1768
1769	/* Create legacy_io and legacy_mem files for this bus */
1770	pci_create_legacy_files(b);
1771
1772	if (parent)
1773		dev_info(parent, "PCI host bridge to bus %s\n", dev_name(&b->dev));
1774	else
1775		printk(KERN_INFO "PCI host bridge to bus %s\n", dev_name(&b->dev));
 
 
 
 
 
 
1776
1777	/* Add initial resources to the bus */
1778	list_for_each_entry_safe(window, n, resources, list) {
1779		list_move_tail(&window->list, &bridge->windows);
1780		res = window->res;
1781		offset = window->offset;
1782		if (res->flags & IORESOURCE_BUS)
1783			pci_bus_insert_busn_res(b, bus, res->end);
1784		else
1785			pci_bus_add_resource(b, res, 0);
1786		if (offset) {
1787			if (resource_type(res) == IORESOURCE_IO)
1788				fmt = " (bus address [%#06llx-%#06llx])";
1789			else
1790				fmt = " (bus address [%#010llx-%#010llx])";
1791			snprintf(bus_addr, sizeof(bus_addr), fmt,
1792				 (unsigned long long) (res->start - offset),
1793				 (unsigned long long) (res->end - offset));
1794		} else
1795			bus_addr[0] = '\0';
1796		dev_info(&b->dev, "root bus resource %pR%s\n", res, bus_addr);
1797	}
1798
1799	down_write(&pci_bus_sem);
1800	list_add_tail(&b->node, &pci_root_buses);
1801	up_write(&pci_bus_sem);
1802
1803	return b;
1804
1805class_dev_reg_err:
1806	put_device(&bridge->dev);
1807	device_unregister(&bridge->dev);
1808err_out:
1809	kfree(b);
1810	return NULL;
1811}
 
1812
1813int pci_bus_insert_busn_res(struct pci_bus *b, int bus, int bus_max)
1814{
1815	struct resource *res = &b->busn_res;
1816	struct resource *parent_res, *conflict;
1817
1818	res->start = bus;
1819	res->end = bus_max;
1820	res->flags = IORESOURCE_BUS;
1821
1822	if (!pci_is_root_bus(b))
1823		parent_res = &b->parent->busn_res;
1824	else {
1825		parent_res = get_pci_domain_busn_res(pci_domain_nr(b));
1826		res->flags |= IORESOURCE_PCI_FIXED;
1827	}
1828
1829	conflict = request_resource_conflict(parent_res, res);
1830
1831	if (conflict)
1832		dev_printk(KERN_DEBUG, &b->dev,
1833			   "busn_res: can not insert %pR under %s%pR (conflicts with %s %pR)\n",
1834			    res, pci_is_root_bus(b) ? "domain " : "",
1835			    parent_res, conflict->name, conflict);
1836
1837	return conflict == NULL;
1838}
1839
1840int pci_bus_update_busn_res_end(struct pci_bus *b, int bus_max)
1841{
1842	struct resource *res = &b->busn_res;
1843	struct resource old_res = *res;
1844	resource_size_t size;
1845	int ret;
1846
1847	if (res->start > bus_max)
1848		return -EINVAL;
1849
1850	size = bus_max - res->start + 1;
1851	ret = adjust_resource(res, res->start, size);
1852	dev_printk(KERN_DEBUG, &b->dev,
1853			"busn_res: %pR end %s updated to %02x\n",
1854			&old_res, ret ? "can not be" : "is", bus_max);
1855
1856	if (!ret && !res->parent)
1857		pci_bus_insert_busn_res(b, res->start, res->end);
1858
1859	return ret;
1860}
1861
1862void pci_bus_release_busn_res(struct pci_bus *b)
1863{
1864	struct resource *res = &b->busn_res;
1865	int ret;
1866
1867	if (!res->flags || !res->parent)
1868		return;
1869
1870	ret = release_resource(res);
1871	dev_printk(KERN_DEBUG, &b->dev,
1872			"busn_res: %pR %s released\n",
1873			res, ret ? "can not be" : "is");
1874}
1875
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1876struct pci_bus *pci_scan_root_bus(struct device *parent, int bus,
1877		struct pci_ops *ops, void *sysdata, struct list_head *resources)
1878{
1879	struct pci_host_bridge_window *window;
1880	bool found = false;
1881	struct pci_bus *b;
1882	int max;
1883
1884	list_for_each_entry(window, resources, list)
1885		if (window->res->flags & IORESOURCE_BUS) {
1886			found = true;
1887			break;
1888		}
1889
1890	b = pci_create_root_bus(parent, bus, ops, sysdata, resources);
1891	if (!b)
1892		return NULL;
1893
1894	if (!found) {
1895		dev_info(&b->dev,
1896		 "No busn resource found for root bus, will use [bus %02x-ff]\n",
1897			bus);
1898		pci_bus_insert_busn_res(b, bus, 255);
1899	}
1900
1901	max = pci_scan_child_bus(b);
1902
1903	if (!found)
1904		pci_bus_update_busn_res_end(b, max);
1905
1906	pci_bus_add_devices(b);
1907	return b;
1908}
1909EXPORT_SYMBOL(pci_scan_root_bus);
1910
1911/* Deprecated; use pci_scan_root_bus() instead */
1912struct pci_bus *pci_scan_bus_parented(struct device *parent,
1913		int bus, struct pci_ops *ops, void *sysdata)
1914{
1915	LIST_HEAD(resources);
1916	struct pci_bus *b;
1917
1918	pci_add_resource(&resources, &ioport_resource);
1919	pci_add_resource(&resources, &iomem_resource);
1920	pci_add_resource(&resources, &busn_resource);
1921	b = pci_create_root_bus(parent, bus, ops, sysdata, &resources);
1922	if (b)
1923		pci_scan_child_bus(b);
1924	else
1925		pci_free_resource_list(&resources);
1926	return b;
1927}
1928EXPORT_SYMBOL(pci_scan_bus_parented);
1929
1930struct pci_bus *pci_scan_bus(int bus, struct pci_ops *ops,
1931					void *sysdata)
1932{
1933	LIST_HEAD(resources);
1934	struct pci_bus *b;
1935
1936	pci_add_resource(&resources, &ioport_resource);
1937	pci_add_resource(&resources, &iomem_resource);
1938	pci_add_resource(&resources, &busn_resource);
1939	b = pci_create_root_bus(NULL, bus, ops, sysdata, &resources);
1940	if (b) {
1941		pci_scan_child_bus(b);
1942		pci_bus_add_devices(b);
1943	} else {
1944		pci_free_resource_list(&resources);
1945	}
1946	return b;
1947}
1948EXPORT_SYMBOL(pci_scan_bus);
1949
1950/**
1951 * pci_rescan_bus_bridge_resize - scan a PCI bus for devices.
1952 * @bridge: PCI bridge for the bus to scan
1953 *
1954 * Scan a PCI bus and child buses for new devices, add them,
1955 * and enable them, resizing bridge mmio/io resource if necessary
1956 * and possible.  The caller must ensure the child devices are already
1957 * removed for resizing to occur.
1958 *
1959 * Returns the max number of subordinate bus discovered.
1960 */
1961unsigned int __ref pci_rescan_bus_bridge_resize(struct pci_dev *bridge)
1962{
1963	unsigned int max;
1964	struct pci_bus *bus = bridge->subordinate;
1965
1966	max = pci_scan_child_bus(bus);
1967
1968	pci_assign_unassigned_bridge_resources(bridge);
1969
1970	pci_bus_add_devices(bus);
1971
1972	return max;
1973}
1974
1975/**
1976 * pci_rescan_bus - scan a PCI bus for devices.
1977 * @bus: PCI bus to scan
1978 *
1979 * Scan a PCI bus and child buses for new devices, adds them,
1980 * and enables them.
1981 *
1982 * Returns the max number of subordinate bus discovered.
1983 */
1984unsigned int __ref pci_rescan_bus(struct pci_bus *bus)
1985{
1986	unsigned int max;
1987
1988	max = pci_scan_child_bus(bus);
1989	pci_assign_unassigned_bus_resources(bus);
1990	pci_bus_add_devices(bus);
1991
1992	return max;
1993}
1994EXPORT_SYMBOL_GPL(pci_rescan_bus);
1995
1996EXPORT_SYMBOL(pci_add_new_bus);
1997EXPORT_SYMBOL(pci_scan_slot);
1998EXPORT_SYMBOL(pci_scan_bridge);
1999EXPORT_SYMBOL_GPL(pci_scan_child_bus);
2000
2001/*
2002 * pci_rescan_bus(), pci_rescan_bus_bridge_resize() and PCI device removal
2003 * routines should always be executed under this mutex.
2004 */
2005static DEFINE_MUTEX(pci_rescan_remove_lock);
2006
2007void pci_lock_rescan_remove(void)
2008{
2009	mutex_lock(&pci_rescan_remove_lock);
2010}
2011EXPORT_SYMBOL_GPL(pci_lock_rescan_remove);
2012
2013void pci_unlock_rescan_remove(void)
2014{
2015	mutex_unlock(&pci_rescan_remove_lock);
2016}
2017EXPORT_SYMBOL_GPL(pci_unlock_rescan_remove);
2018
2019static int __init pci_sort_bf_cmp(const struct device *d_a, const struct device *d_b)
 
2020{
2021	const struct pci_dev *a = to_pci_dev(d_a);
2022	const struct pci_dev *b = to_pci_dev(d_b);
2023
2024	if      (pci_domain_nr(a->bus) < pci_domain_nr(b->bus)) return -1;
2025	else if (pci_domain_nr(a->bus) > pci_domain_nr(b->bus)) return  1;
2026
2027	if      (a->bus->number < b->bus->number) return -1;
2028	else if (a->bus->number > b->bus->number) return  1;
2029
2030	if      (a->devfn < b->devfn) return -1;
2031	else if (a->devfn > b->devfn) return  1;
2032
2033	return 0;
2034}
2035
2036void __init pci_sort_breadthfirst(void)
2037{
2038	bus_sort_breadthfirst(&pci_bus_type, &pci_sort_bf_cmp);
2039}