Linux Audio

Check our new training course

Loading...
v6.13.7
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 *  pci_root.c - ACPI PCI Root Bridge Driver ($Revision: 40 $)
   4 *
   5 *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
   6 *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
   7 */
   8
   9#define pr_fmt(fmt) "ACPI: " fmt
  10
  11#include <linux/kernel.h>
  12#include <linux/module.h>
  13#include <linux/init.h>
  14#include <linux/types.h>
  15#include <linux/mutex.h>
  16#include <linux/pm.h>
  17#include <linux/pm_runtime.h>
  18#include <linux/pci.h>
  19#include <linux/pci-acpi.h>
  20#include <linux/dmar.h>
  21#include <linux/acpi.h>
  22#include <linux/slab.h>
  23#include <linux/dmi.h>
  24#include <linux/platform_data/x86/apple.h>
  25#include "internal.h"
  26
  27#define ACPI_PCI_ROOT_CLASS		"pci_bridge"
  28#define ACPI_PCI_ROOT_DEVICE_NAME	"PCI Root Bridge"
  29static int acpi_pci_root_add(struct acpi_device *device,
  30			     const struct acpi_device_id *not_used);
  31static void acpi_pci_root_remove(struct acpi_device *device);
  32
  33static int acpi_pci_root_scan_dependent(struct acpi_device *adev)
  34{
  35	acpiphp_check_host_bridge(adev);
  36	return 0;
  37}
  38
  39#define ACPI_PCIE_REQ_SUPPORT (OSC_PCI_EXT_CONFIG_SUPPORT \
  40				| OSC_PCI_ASPM_SUPPORT \
  41				| OSC_PCI_CLOCK_PM_SUPPORT \
  42				| OSC_PCI_MSI_SUPPORT)
  43
  44static const struct acpi_device_id root_device_ids[] = {
  45	{"PNP0A03", 0},
  46	{"", 0},
  47};
  48
  49static struct acpi_scan_handler pci_root_handler = {
  50	.ids = root_device_ids,
  51	.attach = acpi_pci_root_add,
  52	.detach = acpi_pci_root_remove,
  53	.hotplug = {
  54		.enabled = true,
  55		.scan_dependent = acpi_pci_root_scan_dependent,
  56	},
  57};
  58
  59/**
  60 * acpi_is_root_bridge - determine whether an ACPI CA node is a PCI root bridge
  61 * @handle:  the ACPI CA node in question.
  62 *
  63 * Note: we could make this API take a struct acpi_device * instead, but
  64 * for now, it's more convenient to operate on an acpi_handle.
  65 */
  66int acpi_is_root_bridge(acpi_handle handle)
  67{
  68	struct acpi_device *device = acpi_fetch_acpi_dev(handle);
  69	int ret;
  70
  71	if (!device)
  72		return 0;
  73
  74	ret = acpi_match_device_ids(device, root_device_ids);
  75	if (ret)
  76		return 0;
  77	else
  78		return 1;
  79}
  80EXPORT_SYMBOL_GPL(acpi_is_root_bridge);
  81
  82static acpi_status
  83get_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
  84{
  85	struct resource *res = data;
  86	struct acpi_resource_address64 address;
  87	acpi_status status;
  88
  89	status = acpi_resource_to_address64(resource, &address);
  90	if (ACPI_FAILURE(status))
  91		return AE_OK;
  92
  93	if ((address.address.address_length > 0) &&
  94	    (address.resource_type == ACPI_BUS_NUMBER_RANGE)) {
  95		res->start = address.address.minimum;
  96		res->end = address.address.minimum + address.address.address_length - 1;
  97	}
  98
  99	return AE_OK;
 100}
 101
 102static acpi_status try_get_root_bridge_busnr(acpi_handle handle,
 103					     struct resource *res)
 104{
 105	acpi_status status;
 106
 107	res->start = -1;
 108	status =
 109	    acpi_walk_resources(handle, METHOD_NAME__CRS,
 110				get_root_bridge_busnr_callback, res);
 111	if (ACPI_FAILURE(status))
 112		return status;
 113	if (res->start == -1)
 114		return AE_ERROR;
 115	return AE_OK;
 116}
 117
 118struct pci_osc_bit_struct {
 119	u32 bit;
 120	char *desc;
 121};
 122
 123static struct pci_osc_bit_struct pci_osc_support_bit[] = {
 124	{ OSC_PCI_EXT_CONFIG_SUPPORT, "ExtendedConfig" },
 125	{ OSC_PCI_ASPM_SUPPORT, "ASPM" },
 126	{ OSC_PCI_CLOCK_PM_SUPPORT, "ClockPM" },
 127	{ OSC_PCI_SEGMENT_GROUPS_SUPPORT, "Segments" },
 128	{ OSC_PCI_MSI_SUPPORT, "MSI" },
 129	{ OSC_PCI_EDR_SUPPORT, "EDR" },
 130	{ OSC_PCI_HPX_TYPE_3_SUPPORT, "HPX-Type3" },
 131};
 132
 133static struct pci_osc_bit_struct pci_osc_control_bit[] = {
 134	{ OSC_PCI_EXPRESS_NATIVE_HP_CONTROL, "PCIeHotplug" },
 135	{ OSC_PCI_SHPC_NATIVE_HP_CONTROL, "SHPCHotplug" },
 136	{ OSC_PCI_EXPRESS_PME_CONTROL, "PME" },
 137	{ OSC_PCI_EXPRESS_AER_CONTROL, "AER" },
 138	{ OSC_PCI_EXPRESS_CAPABILITY_CONTROL, "PCIeCapability" },
 139	{ OSC_PCI_EXPRESS_LTR_CONTROL, "LTR" },
 140	{ OSC_PCI_EXPRESS_DPC_CONTROL, "DPC" },
 141};
 142
 143static struct pci_osc_bit_struct cxl_osc_support_bit[] = {
 144	{ OSC_CXL_1_1_PORT_REG_ACCESS_SUPPORT, "CXL11PortRegAccess" },
 145	{ OSC_CXL_2_0_PORT_DEV_REG_ACCESS_SUPPORT, "CXL20PortDevRegAccess" },
 146	{ OSC_CXL_PROTOCOL_ERR_REPORTING_SUPPORT, "CXLProtocolErrorReporting" },
 147	{ OSC_CXL_NATIVE_HP_SUPPORT, "CXLNativeHotPlug" },
 148};
 149
 150static struct pci_osc_bit_struct cxl_osc_control_bit[] = {
 151	{ OSC_CXL_ERROR_REPORTING_CONTROL, "CXLMemErrorReporting" },
 152};
 153
 154static void decode_osc_bits(struct acpi_pci_root *root, char *msg, u32 word,
 155			    struct pci_osc_bit_struct *table, int size)
 156{
 157	char buf[80];
 158	int i, len = 0;
 159	struct pci_osc_bit_struct *entry;
 160
 161	buf[0] = '\0';
 162	for (i = 0, entry = table; i < size; i++, entry++)
 163		if (word & entry->bit)
 164			len += scnprintf(buf + len, sizeof(buf) - len, "%s%s",
 165					len ? " " : "", entry->desc);
 166
 167	dev_info(&root->device->dev, "_OSC: %s [%s]\n", msg, buf);
 168}
 169
 170static void decode_osc_support(struct acpi_pci_root *root, char *msg, u32 word)
 171{
 172	decode_osc_bits(root, msg, word, pci_osc_support_bit,
 173			ARRAY_SIZE(pci_osc_support_bit));
 174}
 175
 176static void decode_osc_control(struct acpi_pci_root *root, char *msg, u32 word)
 177{
 178	decode_osc_bits(root, msg, word, pci_osc_control_bit,
 179			ARRAY_SIZE(pci_osc_control_bit));
 180}
 181
 182static void decode_cxl_osc_support(struct acpi_pci_root *root, char *msg, u32 word)
 183{
 184	decode_osc_bits(root, msg, word, cxl_osc_support_bit,
 185			ARRAY_SIZE(cxl_osc_support_bit));
 186}
 187
 188static void decode_cxl_osc_control(struct acpi_pci_root *root, char *msg, u32 word)
 189{
 190	decode_osc_bits(root, msg, word, cxl_osc_control_bit,
 191			ARRAY_SIZE(cxl_osc_control_bit));
 192}
 193
 194static inline bool is_pcie(struct acpi_pci_root *root)
 195{
 196	return root->bridge_type == ACPI_BRIDGE_TYPE_PCIE;
 197}
 198
 199static inline bool is_cxl(struct acpi_pci_root *root)
 200{
 201	return root->bridge_type == ACPI_BRIDGE_TYPE_CXL;
 202}
 203
 204static u8 pci_osc_uuid_str[] = "33DB4D5B-1FF7-401C-9657-7441C03DD766";
 205static u8 cxl_osc_uuid_str[] = "68F2D50B-C469-4d8A-BD3D-941A103FD3FC";
 206
 207static char *to_uuid(struct acpi_pci_root *root)
 208{
 209	if (is_cxl(root))
 210		return cxl_osc_uuid_str;
 211	return pci_osc_uuid_str;
 212}
 213
 214static int cap_length(struct acpi_pci_root *root)
 215{
 216	if (is_cxl(root))
 217		return sizeof(u32) * OSC_CXL_CAPABILITY_DWORDS;
 218	return sizeof(u32) * OSC_PCI_CAPABILITY_DWORDS;
 219}
 220
 221static acpi_status acpi_pci_run_osc(struct acpi_pci_root *root,
 222				    const u32 *capbuf, u32 *pci_control,
 223				    u32 *cxl_control)
 224{
 225	struct acpi_osc_context context = {
 226		.uuid_str = to_uuid(root),
 227		.rev = 1,
 228		.cap.length = cap_length(root),
 229		.cap.pointer = (void *)capbuf,
 230	};
 231	acpi_status status;
 232
 233	status = acpi_run_osc(root->device->handle, &context);
 234	if (ACPI_SUCCESS(status)) {
 235		*pci_control = acpi_osc_ctx_get_pci_control(&context);
 236		if (is_cxl(root))
 237			*cxl_control = acpi_osc_ctx_get_cxl_control(&context);
 238		kfree(context.ret.pointer);
 239	}
 240	return status;
 241}
 242
 243static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root, u32 support,
 244				      u32 *control, u32 cxl_support,
 245				      u32 *cxl_control)
 246{
 247	acpi_status status;
 248	u32 pci_result, cxl_result, capbuf[OSC_CXL_CAPABILITY_DWORDS];
 249
 250	support |= root->osc_support_set;
 251
 252	capbuf[OSC_QUERY_DWORD] = OSC_QUERY_ENABLE;
 253	capbuf[OSC_SUPPORT_DWORD] = support;
 254	capbuf[OSC_CONTROL_DWORD] = *control | root->osc_control_set;
 255
 256	if (is_cxl(root)) {
 257		cxl_support |= root->osc_ext_support_set;
 258		capbuf[OSC_EXT_SUPPORT_DWORD] = cxl_support;
 259		capbuf[OSC_EXT_CONTROL_DWORD] = *cxl_control | root->osc_ext_control_set;
 260	}
 261
 262retry:
 263	status = acpi_pci_run_osc(root, capbuf, &pci_result, &cxl_result);
 264	if (ACPI_SUCCESS(status)) {
 265		root->osc_support_set = support;
 266		*control = pci_result;
 267		if (is_cxl(root)) {
 268			root->osc_ext_support_set = cxl_support;
 269			*cxl_control = cxl_result;
 270		}
 271	} else if (is_cxl(root)) {
 272		/*
 273		 * CXL _OSC is optional on CXL 1.1 hosts. Fall back to PCIe _OSC
 274		 * upon any failure using CXL _OSC.
 275		 */
 276		root->bridge_type = ACPI_BRIDGE_TYPE_PCIE;
 277		goto retry;
 278	}
 279	return status;
 280}
 281
 282struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle)
 283{
 284	struct acpi_device *device = acpi_fetch_acpi_dev(handle);
 285	struct acpi_pci_root *root;
 286
 287	if (!device || acpi_match_device_ids(device, root_device_ids))
 288		return NULL;
 289
 290	root = acpi_driver_data(device);
 291
 292	return root;
 293}
 294EXPORT_SYMBOL_GPL(acpi_pci_find_root);
 295
 
 
 
 
 
 296/**
 297 * acpi_get_pci_dev - convert ACPI CA handle to struct pci_dev
 298 * @handle: the handle in question
 299 *
 300 * Given an ACPI CA handle, the desired PCI device is located in the
 301 * list of PCI devices.
 302 *
 303 * If the device is found, its reference count is increased and this
 304 * function returns a pointer to its data structure.  The caller must
 305 * decrement the reference count by calling pci_dev_put().
 306 * If no device is found, %NULL is returned.
 307 */
 308struct pci_dev *acpi_get_pci_dev(acpi_handle handle)
 309{
 310	struct acpi_device *adev = acpi_fetch_acpi_dev(handle);
 311	struct acpi_device_physical_node *pn;
 312	struct pci_dev *pci_dev = NULL;
 313
 314	if (!adev)
 315		return NULL;
 316
 317	mutex_lock(&adev->physical_node_lock);
 318
 319	list_for_each_entry(pn, &adev->physical_node_list, node) {
 320		if (dev_is_pci(pn->dev)) {
 321			get_device(pn->dev);
 322			pci_dev = to_pci_dev(pn->dev);
 323			break;
 324		}
 325	}
 326
 327	mutex_unlock(&adev->physical_node_lock);
 328
 329	return pci_dev;
 330}
 331EXPORT_SYMBOL_GPL(acpi_get_pci_dev);
 332
 333/**
 334 * acpi_pci_osc_control_set - Request control of PCI root _OSC features.
 335 * @handle: ACPI handle of a PCI root bridge (or PCIe Root Complex).
 336 * @mask: Mask of _OSC bits to request control of, place to store control mask.
 337 * @support: _OSC supported capability.
 338 * @cxl_mask: Mask of CXL _OSC control bits, place to store control mask.
 339 * @cxl_support: CXL _OSC supported capability.
 340 *
 341 * Run _OSC query for @mask and if that is successful, compare the returned
 342 * mask of control bits with @req.  If all of the @req bits are set in the
 343 * returned mask, run _OSC request for it.
 344 *
 345 * The variable at the @mask address may be modified regardless of whether or
 346 * not the function returns success.  On success it will contain the mask of
 347 * _OSC bits the BIOS has granted control of, but its contents are meaningless
 348 * on failure.
 349 **/
 350static acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 *mask,
 351					    u32 support, u32 *cxl_mask,
 352					    u32 cxl_support)
 353{
 354	u32 req = OSC_PCI_EXPRESS_CAPABILITY_CONTROL;
 355	struct acpi_pci_root *root;
 356	acpi_status status;
 357	u32 ctrl, cxl_ctrl = 0, capbuf[OSC_CXL_CAPABILITY_DWORDS];
 358
 359	if (!mask)
 360		return AE_BAD_PARAMETER;
 361
 362	root = acpi_pci_find_root(handle);
 363	if (!root)
 364		return AE_NOT_EXIST;
 365
 366	ctrl   = *mask;
 367	*mask |= root->osc_control_set;
 368
 369	if (is_cxl(root)) {
 370		cxl_ctrl = *cxl_mask;
 371		*cxl_mask |= root->osc_ext_control_set;
 372	}
 373
 374	/* Need to check the available controls bits before requesting them. */
 375	do {
 376		u32 pci_missing = 0, cxl_missing = 0;
 377
 378		status = acpi_pci_query_osc(root, support, mask, cxl_support,
 379					    cxl_mask);
 380		if (ACPI_FAILURE(status))
 381			return status;
 382		if (is_cxl(root)) {
 383			if (ctrl == *mask && cxl_ctrl == *cxl_mask)
 384				break;
 385			pci_missing = ctrl & ~(*mask);
 386			cxl_missing = cxl_ctrl & ~(*cxl_mask);
 387		} else {
 388			if (ctrl == *mask)
 389				break;
 390			pci_missing = ctrl & ~(*mask);
 391		}
 392		if (pci_missing)
 393			decode_osc_control(root, "platform does not support",
 394					   pci_missing);
 395		if (cxl_missing)
 396			decode_cxl_osc_control(root, "CXL platform does not support",
 397					   cxl_missing);
 398		ctrl = *mask;
 399		cxl_ctrl = *cxl_mask;
 400	} while (*mask || *cxl_mask);
 401
 402	/* No need to request _OSC if the control was already granted. */
 403	if ((root->osc_control_set & ctrl) == ctrl &&
 404	    (root->osc_ext_control_set & cxl_ctrl) == cxl_ctrl)
 405		return AE_OK;
 406
 407	if ((ctrl & req) != req) {
 408		decode_osc_control(root, "not requesting control; platform does not support",
 409				   req & ~(ctrl));
 410		return AE_SUPPORT;
 411	}
 412
 413	capbuf[OSC_QUERY_DWORD] = 0;
 414	capbuf[OSC_SUPPORT_DWORD] = root->osc_support_set;
 415	capbuf[OSC_CONTROL_DWORD] = ctrl;
 416	if (is_cxl(root)) {
 417		capbuf[OSC_EXT_SUPPORT_DWORD] = root->osc_ext_support_set;
 418		capbuf[OSC_EXT_CONTROL_DWORD] = cxl_ctrl;
 419	}
 420
 421	status = acpi_pci_run_osc(root, capbuf, mask, cxl_mask);
 422	if (ACPI_FAILURE(status))
 423		return status;
 424
 425	root->osc_control_set = *mask;
 426	root->osc_ext_control_set = *cxl_mask;
 427	return AE_OK;
 428}
 429
 430static u32 calculate_support(void)
 431{
 432	u32 support;
 433
 434	/*
 435	 * All supported architectures that use ACPI have support for
 436	 * PCI domains, so we indicate this in _OSC support capabilities.
 437	 */
 438	support = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
 439	support |= OSC_PCI_HPX_TYPE_3_SUPPORT;
 440	if (pci_ext_cfg_avail())
 441		support |= OSC_PCI_EXT_CONFIG_SUPPORT;
 442	if (pcie_aspm_support_enabled())
 443		support |= OSC_PCI_ASPM_SUPPORT | OSC_PCI_CLOCK_PM_SUPPORT;
 444	if (pci_msi_enabled())
 445		support |= OSC_PCI_MSI_SUPPORT;
 446	if (IS_ENABLED(CONFIG_PCIE_EDR))
 447		support |= OSC_PCI_EDR_SUPPORT;
 448
 449	return support;
 450}
 451
 452/*
 453 * Background on hotplug support, and making it depend on only
 454 * CONFIG_HOTPLUG_PCI_PCIE vs. also considering CONFIG_MEMORY_HOTPLUG:
 455 *
 456 * CONFIG_ACPI_HOTPLUG_MEMORY does depend on CONFIG_MEMORY_HOTPLUG, but
 457 * there is no existing _OSC for memory hotplug support. The reason is that
 458 * ACPI memory hotplug requires the OS to acknowledge / coordinate with
 459 * memory plug events via a scan handler. On the CXL side the equivalent
 460 * would be if Linux supported the Mechanical Retention Lock [1], or
 461 * otherwise had some coordination for the driver of a PCI device
 462 * undergoing hotplug to be consulted on whether the hotplug should
 463 * proceed or not.
 464 *
 465 * The concern is that if Linux says no to supporting CXL hotplug then
 466 * the BIOS may say no to giving the OS hotplug control of any other PCIe
 467 * device. So the question here is not whether hotplug is enabled, it's
 468 * whether it is handled natively by the at all OS, and if
 469 * CONFIG_HOTPLUG_PCI_PCIE is enabled then the answer is "yes".
 470 *
 471 * Otherwise, the plan for CXL coordinated remove, since the kernel does
 472 * not support blocking hotplug, is to require the memory device to be
 473 * disabled before hotplug is attempted. When CONFIG_MEMORY_HOTPLUG is
 474 * disabled that step will fail and the remove attempt cancelled by the
 475 * user. If that is not honored and the card is removed anyway then it
 476 * does not matter if CONFIG_MEMORY_HOTPLUG is enabled or not, it will
 477 * cause a crash and other badness.
 478 *
 479 * Therefore, just say yes to CXL hotplug and require removal to
 480 * be coordinated by userspace unless and until the kernel grows better
 481 * mechanisms for doing "managed" removal of devices in consultation with
 482 * the driver.
 483 *
 484 * [1]: https://lore.kernel.org/all/20201122014203.4706-1-ashok.raj@intel.com/
 485 */
 486static u32 calculate_cxl_support(void)
 487{
 488	u32 support;
 489
 490	support = OSC_CXL_2_0_PORT_DEV_REG_ACCESS_SUPPORT;
 491	support |= OSC_CXL_1_1_PORT_REG_ACCESS_SUPPORT;
 492	if (pci_aer_available())
 493		support |= OSC_CXL_PROTOCOL_ERR_REPORTING_SUPPORT;
 494	if (IS_ENABLED(CONFIG_HOTPLUG_PCI_PCIE))
 495		support |= OSC_CXL_NATIVE_HP_SUPPORT;
 496
 497	return support;
 498}
 499
 500static u32 calculate_control(void)
 501{
 502	u32 control;
 503
 504	control = OSC_PCI_EXPRESS_CAPABILITY_CONTROL
 505		| OSC_PCI_EXPRESS_PME_CONTROL;
 506
 507	if (IS_ENABLED(CONFIG_PCIEASPM))
 508		control |= OSC_PCI_EXPRESS_LTR_CONTROL;
 509
 510	if (IS_ENABLED(CONFIG_HOTPLUG_PCI_PCIE))
 511		control |= OSC_PCI_EXPRESS_NATIVE_HP_CONTROL;
 512
 513	if (IS_ENABLED(CONFIG_HOTPLUG_PCI_SHPC))
 514		control |= OSC_PCI_SHPC_NATIVE_HP_CONTROL;
 515
 516	if (pci_aer_available())
 517		control |= OSC_PCI_EXPRESS_AER_CONTROL;
 518
 519	/*
 520	 * Per the Downstream Port Containment Related Enhancements ECN to
 521	 * the PCI Firmware Spec, r3.2, sec 4.5.1, table 4-5,
 522	 * OSC_PCI_EXPRESS_DPC_CONTROL indicates the OS supports both DPC
 523	 * and EDR.
 524	 */
 525	if (IS_ENABLED(CONFIG_PCIE_DPC) && IS_ENABLED(CONFIG_PCIE_EDR))
 526		control |= OSC_PCI_EXPRESS_DPC_CONTROL;
 527
 528	return control;
 529}
 530
 531static u32 calculate_cxl_control(void)
 532{
 533	u32 control = 0;
 534
 535	if (IS_ENABLED(CONFIG_MEMORY_FAILURE))
 536		control |= OSC_CXL_ERROR_REPORTING_CONTROL;
 537
 538	return control;
 539}
 540
 541static bool os_control_query_checks(struct acpi_pci_root *root, u32 support)
 542{
 543	struct acpi_device *device = root->device;
 544
 545	if (pcie_ports_disabled) {
 546		dev_info(&device->dev, "PCIe port services disabled; not requesting _OSC control\n");
 547		return false;
 548	}
 549
 550	if ((support & ACPI_PCIE_REQ_SUPPORT) != ACPI_PCIE_REQ_SUPPORT) {
 551		decode_osc_support(root, "not requesting OS control; OS requires",
 552				   ACPI_PCIE_REQ_SUPPORT);
 553		return false;
 554	}
 555
 556	return true;
 557}
 558
 559static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm)
 560{
 561	u32 support, control = 0, requested = 0;
 562	u32 cxl_support = 0, cxl_control = 0, cxl_requested = 0;
 563	acpi_status status;
 564	struct acpi_device *device = root->device;
 565	acpi_handle handle = device->handle;
 566
 567	/*
 568	 * Apple always return failure on _OSC calls when _OSI("Darwin") has
 569	 * been called successfully. We know the feature set supported by the
 570	 * platform, so avoid calling _OSC at all
 571	 */
 572	if (x86_apple_machine) {
 573		root->osc_control_set = ~OSC_PCI_EXPRESS_PME_CONTROL;
 574		decode_osc_control(root, "OS assumes control of",
 575				   root->osc_control_set);
 576		return;
 577	}
 578
 579	support = calculate_support();
 580
 581	decode_osc_support(root, "OS supports", support);
 582
 583	if (os_control_query_checks(root, support))
 584		requested = control = calculate_control();
 585
 586	if (is_cxl(root)) {
 587		cxl_support = calculate_cxl_support();
 588		decode_cxl_osc_support(root, "OS supports", cxl_support);
 589		cxl_requested = cxl_control = calculate_cxl_control();
 590	}
 591
 592	status = acpi_pci_osc_control_set(handle, &control, support,
 593					  &cxl_control, cxl_support);
 594	if (ACPI_SUCCESS(status)) {
 595		if (control)
 596			decode_osc_control(root, "OS now controls", control);
 597		if (cxl_control)
 598			decode_cxl_osc_control(root, "OS now controls",
 599					   cxl_control);
 600
 601		if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) {
 602			/*
 603			 * We have ASPM control, but the FADT indicates that
 604			 * it's unsupported. Leave existing configuration
 605			 * intact and prevent the OS from touching it.
 606			 */
 607			dev_info(&device->dev, "FADT indicates ASPM is unsupported, using BIOS configuration\n");
 608			*no_aspm = 1;
 609		}
 610	} else {
 611		/*
 612		 * We want to disable ASPM here, but aspm_disabled
 613		 * needs to remain in its state from boot so that we
 614		 * properly handle PCIe 1.1 devices.  So we set this
 615		 * flag here, to defer the action until after the ACPI
 616		 * root scan.
 617		 */
 618		*no_aspm = 1;
 619
 620		/* _OSC is optional for PCI host bridges */
 621		if (status == AE_NOT_FOUND && !is_pcie(root))
 622			return;
 623
 624		if (control) {
 625			decode_osc_control(root, "OS requested", requested);
 626			decode_osc_control(root, "platform willing to grant", control);
 627		}
 628		if (cxl_control) {
 629			decode_cxl_osc_control(root, "OS requested", cxl_requested);
 630			decode_cxl_osc_control(root, "platform willing to grant",
 631					   cxl_control);
 632		}
 633
 634		dev_info(&device->dev, "_OSC: platform retains control of PCIe features (%s)\n",
 635			 acpi_format_exception(status));
 636	}
 637}
 638
 639static int acpi_pci_root_add(struct acpi_device *device,
 640			     const struct acpi_device_id *not_used)
 641{
 642	unsigned long long segment, bus;
 643	acpi_status status;
 644	int result;
 645	struct acpi_pci_root *root;
 646	acpi_handle handle = device->handle;
 647	int no_aspm = 0;
 648	bool hotadd = system_state == SYSTEM_RUNNING;
 649	const char *acpi_hid;
 650
 651	root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
 652	if (!root)
 653		return -ENOMEM;
 654
 655	segment = 0;
 656	status = acpi_evaluate_integer(handle, METHOD_NAME__SEG, NULL,
 657				       &segment);
 658	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 659		dev_err(&device->dev,  "can't evaluate _SEG\n");
 660		result = -ENODEV;
 661		goto end;
 662	}
 663
 664	/* Check _CRS first, then _BBN.  If no _BBN, default to zero. */
 665	root->secondary.flags = IORESOURCE_BUS;
 666	status = try_get_root_bridge_busnr(handle, &root->secondary);
 667	if (ACPI_FAILURE(status)) {
 668		/*
 669		 * We need both the start and end of the downstream bus range
 670		 * to interpret _CBA (MMCONFIG base address), so it really is
 671		 * supposed to be in _CRS.  If we don't find it there, all we
 672		 * can do is assume [_BBN-0xFF] or [0-0xFF].
 673		 */
 674		root->secondary.end = 0xFF;
 675		dev_warn(&device->dev,
 676			 FW_BUG "no secondary bus range in _CRS\n");
 677		status = acpi_evaluate_integer(handle, METHOD_NAME__BBN,
 678					       NULL, &bus);
 679		if (ACPI_SUCCESS(status))
 680			root->secondary.start = bus;
 681		else if (status == AE_NOT_FOUND)
 682			root->secondary.start = 0;
 683		else {
 684			dev_err(&device->dev, "can't evaluate _BBN\n");
 685			result = -ENODEV;
 686			goto end;
 687		}
 688	}
 689
 690	root->device = device;
 691	root->segment = segment & 0xFFFF;
 692	strscpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
 693	strscpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
 694	device->driver_data = root;
 695
 696	if (hotadd && dmar_device_add(handle)) {
 697		result = -ENXIO;
 698		goto end;
 699	}
 700
 701	pr_info("%s [%s] (domain %04x %pR)\n",
 702	       acpi_device_name(device), acpi_device_bid(device),
 703	       root->segment, &root->secondary);
 704
 705	root->mcfg_addr = acpi_pci_root_get_mcfg_addr(handle);
 706
 707	acpi_hid = acpi_device_hid(root->device);
 708	if (strcmp(acpi_hid, "PNP0A08") == 0)
 709		root->bridge_type = ACPI_BRIDGE_TYPE_PCIE;
 710	else if (strcmp(acpi_hid, "ACPI0016") == 0)
 711		root->bridge_type = ACPI_BRIDGE_TYPE_CXL;
 712	else
 713		dev_dbg(&device->dev, "Assuming non-PCIe host bridge\n");
 714
 715	negotiate_os_control(root, &no_aspm);
 716
 717	/*
 718	 * TBD: Need PCI interface for enumeration/configuration of roots.
 719	 */
 720
 721	/*
 722	 * Scan the Root Bridge
 723	 * --------------------
 724	 * Must do this prior to any attempt to bind the root device, as the
 725	 * PCI namespace does not get created until this call is made (and
 726	 * thus the root bridge's pci_dev does not exist).
 727	 */
 728	root->bus = pci_acpi_scan_root(root);
 729	if (!root->bus) {
 730		dev_err(&device->dev,
 731			"Bus %04x:%02x not present in PCI namespace\n",
 732			root->segment, (unsigned int)root->secondary.start);
 733		device->driver_data = NULL;
 734		result = -ENODEV;
 735		goto remove_dmar;
 736	}
 737
 738	if (no_aspm)
 739		pcie_no_aspm();
 740
 741	pci_acpi_add_bus_pm_notifier(device);
 742	device_set_wakeup_capable(root->bus->bridge, device->wakeup.flags.valid);
 743
 744	if (hotadd) {
 745		pcibios_resource_survey_bus(root->bus);
 746		pci_assign_unassigned_root_bus_resources(root->bus);
 747		/*
 748		 * This is only called for the hotadd case. For the boot-time
 749		 * case, we need to wait until after PCI initialization in
 750		 * order to deal with IOAPICs mapped in on a PCI BAR.
 751		 *
 752		 * This is currently x86-specific, because acpi_ioapic_add()
 753		 * is an empty function without CONFIG_ACPI_HOTPLUG_IOAPIC.
 754		 * And CONFIG_ACPI_HOTPLUG_IOAPIC depends on CONFIG_X86_IO_APIC
 755		 * (see drivers/acpi/Kconfig).
 756		 */
 757		acpi_ioapic_add(root->device->handle);
 758	}
 759
 760	pci_lock_rescan_remove();
 761	pci_bus_add_devices(root->bus);
 762	pci_unlock_rescan_remove();
 763	return 1;
 764
 765remove_dmar:
 766	if (hotadd)
 767		dmar_device_remove(handle);
 768end:
 769	kfree(root);
 770	return result;
 771}
 772
 773static void acpi_pci_root_remove(struct acpi_device *device)
 774{
 775	struct acpi_pci_root *root = acpi_driver_data(device);
 776
 777	pci_lock_rescan_remove();
 778
 779	pci_stop_root_bus(root->bus);
 780
 781	pci_ioapic_remove(root);
 782	device_set_wakeup_capable(root->bus->bridge, false);
 783	pci_acpi_remove_bus_pm_notifier(device);
 784
 785	pci_remove_root_bus(root->bus);
 786	WARN_ON(acpi_ioapic_remove(root));
 787
 788	dmar_device_remove(device->handle);
 789
 790	pci_unlock_rescan_remove();
 791
 792	kfree(root);
 793}
 794
 795/*
 796 * Following code to support acpi_pci_root_create() is copied from
 797 * arch/x86/pci/acpi.c and modified so it could be reused by x86, IA64
 798 * and ARM64.
 799 */
 800static void acpi_pci_root_validate_resources(struct device *dev,
 801					     struct list_head *resources,
 802					     unsigned long type)
 803{
 804	LIST_HEAD(list);
 805	struct resource *res1, *res2, *root = NULL;
 806	struct resource_entry *tmp, *entry, *entry2;
 807
 808	BUG_ON((type & (IORESOURCE_MEM | IORESOURCE_IO)) == 0);
 809	root = (type & IORESOURCE_MEM) ? &iomem_resource : &ioport_resource;
 810
 811	list_splice_init(resources, &list);
 812	resource_list_for_each_entry_safe(entry, tmp, &list) {
 813		bool free = false;
 814		resource_size_t end;
 815
 816		res1 = entry->res;
 817		if (!(res1->flags & type))
 818			goto next;
 819
 820		/* Exclude non-addressable range or non-addressable portion */
 821		end = min(res1->end, root->end);
 822		if (end <= res1->start) {
 823			dev_info(dev, "host bridge window %pR (ignored, not CPU addressable)\n",
 824				 res1);
 825			free = true;
 826			goto next;
 827		} else if (res1->end != end) {
 828			dev_info(dev, "host bridge window %pR ([%#llx-%#llx] ignored, not CPU addressable)\n",
 829				 res1, (unsigned long long)end + 1,
 830				 (unsigned long long)res1->end);
 831			res1->end = end;
 832		}
 833
 834		resource_list_for_each_entry(entry2, resources) {
 835			res2 = entry2->res;
 836			if (!(res2->flags & type))
 837				continue;
 838
 839			/*
 840			 * I don't like throwing away windows because then
 841			 * our resources no longer match the ACPI _CRS, but
 842			 * the kernel resource tree doesn't allow overlaps.
 843			 */
 844			if (resource_union(res1, res2, res2)) {
 845				dev_info(dev, "host bridge window expanded to %pR; %pR ignored\n",
 846					 res2, res1);
 847				free = true;
 848				goto next;
 849			}
 850		}
 851
 852next:
 853		resource_list_del(entry);
 854		if (free)
 855			resource_list_free_entry(entry);
 856		else
 857			resource_list_add_tail(entry, resources);
 858	}
 859}
 860
 861static void acpi_pci_root_remap_iospace(struct fwnode_handle *fwnode,
 862			struct resource_entry *entry)
 863{
 864#ifdef PCI_IOBASE
 865	struct resource *res = entry->res;
 866	resource_size_t cpu_addr = res->start;
 867	resource_size_t pci_addr = cpu_addr - entry->offset;
 868	resource_size_t length = resource_size(res);
 869	unsigned long port;
 870
 871	if (pci_register_io_range(fwnode, cpu_addr, length))
 872		goto err;
 873
 874	port = pci_address_to_pio(cpu_addr);
 875	if (port == (unsigned long)-1)
 876		goto err;
 877
 878	res->start = port;
 879	res->end = port + length - 1;
 880	entry->offset = port - pci_addr;
 881
 882	if (pci_remap_iospace(res, cpu_addr) < 0)
 883		goto err;
 884
 885	pr_info("Remapped I/O %pa to %pR\n", &cpu_addr, res);
 886	return;
 887err:
 888	res->flags |= IORESOURCE_DISABLED;
 889#endif
 890}
 891
 892int acpi_pci_probe_root_resources(struct acpi_pci_root_info *info)
 893{
 894	int ret;
 895	struct list_head *list = &info->resources;
 896	struct acpi_device *device = info->bridge;
 897	struct resource_entry *entry, *tmp;
 898	unsigned long flags;
 899
 900	flags = IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_MEM_8AND16BIT;
 901	ret = acpi_dev_get_resources(device, list,
 902				     acpi_dev_filter_resource_type_cb,
 903				     (void *)flags);
 904	if (ret < 0)
 905		dev_warn(&device->dev,
 906			 "failed to parse _CRS method, error code %d\n", ret);
 907	else if (ret == 0)
 908		dev_dbg(&device->dev,
 909			"no IO and memory resources present in _CRS\n");
 910	else {
 911		resource_list_for_each_entry_safe(entry, tmp, list) {
 912			if (entry->res->flags & IORESOURCE_IO)
 913				acpi_pci_root_remap_iospace(&device->fwnode,
 914						entry);
 915
 916			if (entry->res->flags & IORESOURCE_DISABLED)
 917				resource_list_destroy_entry(entry);
 918			else
 919				entry->res->name = info->name;
 920		}
 921		acpi_pci_root_validate_resources(&device->dev, list,
 922						 IORESOURCE_MEM);
 923		acpi_pci_root_validate_resources(&device->dev, list,
 924						 IORESOURCE_IO);
 925	}
 926
 927	return ret;
 928}
 929
 930static void pci_acpi_root_add_resources(struct acpi_pci_root_info *info)
 931{
 932	struct resource_entry *entry, *tmp;
 933	struct resource *res, *conflict, *root = NULL;
 934
 935	resource_list_for_each_entry_safe(entry, tmp, &info->resources) {
 936		res = entry->res;
 937		if (res->flags & IORESOURCE_MEM)
 938			root = &iomem_resource;
 939		else if (res->flags & IORESOURCE_IO)
 940			root = &ioport_resource;
 941		else
 942			continue;
 943
 944		/*
 945		 * Some legacy x86 host bridge drivers use iomem_resource and
 946		 * ioport_resource as default resource pool, skip it.
 947		 */
 948		if (res == root)
 949			continue;
 950
 951		conflict = insert_resource_conflict(root, res);
 952		if (conflict) {
 953			dev_info(&info->bridge->dev,
 954				 "ignoring host bridge window %pR (conflicts with %s %pR)\n",
 955				 res, conflict->name, conflict);
 956			resource_list_destroy_entry(entry);
 957		}
 958	}
 959}
 960
 961static void __acpi_pci_root_release_info(struct acpi_pci_root_info *info)
 962{
 963	struct resource *res;
 964	struct resource_entry *entry, *tmp;
 965
 966	if (!info)
 967		return;
 968
 969	resource_list_for_each_entry_safe(entry, tmp, &info->resources) {
 970		res = entry->res;
 971		if (res->parent &&
 972		    (res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
 973			release_resource(res);
 974		resource_list_destroy_entry(entry);
 975	}
 976
 977	info->ops->release_info(info);
 978}
 979
 980static void acpi_pci_root_release_info(struct pci_host_bridge *bridge)
 981{
 982	struct resource *res;
 983	struct resource_entry *entry;
 984
 985	resource_list_for_each_entry(entry, &bridge->windows) {
 986		res = entry->res;
 987		if (res->flags & IORESOURCE_IO)
 988			pci_unmap_iospace(res);
 989		if (res->parent &&
 990		    (res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
 991			release_resource(res);
 992	}
 993	__acpi_pci_root_release_info(bridge->release_data);
 994}
 995
 996struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root,
 997				     struct acpi_pci_root_ops *ops,
 998				     struct acpi_pci_root_info *info,
 999				     void *sysdata)
1000{
1001	int ret, busnum = root->secondary.start;
1002	struct acpi_device *device = root->device;
1003	int node = acpi_get_node(device->handle);
1004	struct pci_bus *bus;
1005	struct pci_host_bridge *host_bridge;
 
1006
1007	info->root = root;
1008	info->bridge = device;
1009	info->ops = ops;
1010	INIT_LIST_HEAD(&info->resources);
1011	snprintf(info->name, sizeof(info->name), "PCI Bus %04x:%02x",
1012		 root->segment, busnum);
1013
1014	if (ops->init_info && ops->init_info(info))
1015		goto out_release_info;
1016	if (ops->prepare_resources)
1017		ret = ops->prepare_resources(info);
1018	else
1019		ret = acpi_pci_probe_root_resources(info);
1020	if (ret < 0)
1021		goto out_release_info;
1022
1023	pci_acpi_root_add_resources(info);
1024	pci_add_resource(&info->resources, &root->secondary);
1025	bus = pci_create_root_bus(NULL, busnum, ops->pci_ops,
1026				  sysdata, &info->resources);
1027	if (!bus)
1028		goto out_release_info;
1029
1030	host_bridge = to_pci_host_bridge(bus->bridge);
1031	if (!(root->osc_control_set & OSC_PCI_EXPRESS_NATIVE_HP_CONTROL))
1032		host_bridge->native_pcie_hotplug = 0;
1033	if (!(root->osc_control_set & OSC_PCI_SHPC_NATIVE_HP_CONTROL))
1034		host_bridge->native_shpc_hotplug = 0;
1035	if (!(root->osc_control_set & OSC_PCI_EXPRESS_AER_CONTROL))
1036		host_bridge->native_aer = 0;
1037	if (!(root->osc_control_set & OSC_PCI_EXPRESS_PME_CONTROL))
1038		host_bridge->native_pme = 0;
1039	if (!(root->osc_control_set & OSC_PCI_EXPRESS_LTR_CONTROL))
1040		host_bridge->native_ltr = 0;
1041	if (!(root->osc_control_set & OSC_PCI_EXPRESS_DPC_CONTROL))
1042		host_bridge->native_dpc = 0;
1043
1044	if (!(root->osc_ext_control_set & OSC_CXL_ERROR_REPORTING_CONTROL))
1045		host_bridge->native_cxl_error = 0;
 
 
 
 
 
 
 
 
1046
1047	acpi_dev_power_up_children_with_adr(device);
1048
1049	pci_scan_child_bus(bus);
1050	pci_set_host_bridge_release(host_bridge, acpi_pci_root_release_info,
1051				    info);
1052	if (node != NUMA_NO_NODE)
1053		dev_printk(KERN_DEBUG, &bus->dev, "on NUMA node %d\n", node);
1054	return bus;
1055
1056out_release_info:
1057	__acpi_pci_root_release_info(info);
1058	return NULL;
1059}
1060
1061void __init acpi_pci_root_init(void)
1062{
1063	if (acpi_pci_disabled)
1064		return;
1065
1066	pci_acpi_crs_quirks();
1067	acpi_scan_add_handler_with_hotplug(&pci_root_handler, "pci_root");
1068}
v6.2
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 *  pci_root.c - ACPI PCI Root Bridge Driver ($Revision: 40 $)
   4 *
   5 *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
   6 *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
   7 */
   8
   9#define pr_fmt(fmt) "ACPI: " fmt
  10
  11#include <linux/kernel.h>
  12#include <linux/module.h>
  13#include <linux/init.h>
  14#include <linux/types.h>
  15#include <linux/mutex.h>
  16#include <linux/pm.h>
  17#include <linux/pm_runtime.h>
  18#include <linux/pci.h>
  19#include <linux/pci-acpi.h>
  20#include <linux/dmar.h>
  21#include <linux/acpi.h>
  22#include <linux/slab.h>
  23#include <linux/dmi.h>
  24#include <linux/platform_data/x86/apple.h>
  25#include "internal.h"
  26
  27#define ACPI_PCI_ROOT_CLASS		"pci_bridge"
  28#define ACPI_PCI_ROOT_DEVICE_NAME	"PCI Root Bridge"
  29static int acpi_pci_root_add(struct acpi_device *device,
  30			     const struct acpi_device_id *not_used);
  31static void acpi_pci_root_remove(struct acpi_device *device);
  32
  33static int acpi_pci_root_scan_dependent(struct acpi_device *adev)
  34{
  35	acpiphp_check_host_bridge(adev);
  36	return 0;
  37}
  38
  39#define ACPI_PCIE_REQ_SUPPORT (OSC_PCI_EXT_CONFIG_SUPPORT \
  40				| OSC_PCI_ASPM_SUPPORT \
  41				| OSC_PCI_CLOCK_PM_SUPPORT \
  42				| OSC_PCI_MSI_SUPPORT)
  43
  44static const struct acpi_device_id root_device_ids[] = {
  45	{"PNP0A03", 0},
  46	{"", 0},
  47};
  48
  49static struct acpi_scan_handler pci_root_handler = {
  50	.ids = root_device_ids,
  51	.attach = acpi_pci_root_add,
  52	.detach = acpi_pci_root_remove,
  53	.hotplug = {
  54		.enabled = true,
  55		.scan_dependent = acpi_pci_root_scan_dependent,
  56	},
  57};
  58
  59/**
  60 * acpi_is_root_bridge - determine whether an ACPI CA node is a PCI root bridge
  61 * @handle:  the ACPI CA node in question.
  62 *
  63 * Note: we could make this API take a struct acpi_device * instead, but
  64 * for now, it's more convenient to operate on an acpi_handle.
  65 */
  66int acpi_is_root_bridge(acpi_handle handle)
  67{
  68	struct acpi_device *device = acpi_fetch_acpi_dev(handle);
  69	int ret;
  70
  71	if (!device)
  72		return 0;
  73
  74	ret = acpi_match_device_ids(device, root_device_ids);
  75	if (ret)
  76		return 0;
  77	else
  78		return 1;
  79}
  80EXPORT_SYMBOL_GPL(acpi_is_root_bridge);
  81
  82static acpi_status
  83get_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
  84{
  85	struct resource *res = data;
  86	struct acpi_resource_address64 address;
  87	acpi_status status;
  88
  89	status = acpi_resource_to_address64(resource, &address);
  90	if (ACPI_FAILURE(status))
  91		return AE_OK;
  92
  93	if ((address.address.address_length > 0) &&
  94	    (address.resource_type == ACPI_BUS_NUMBER_RANGE)) {
  95		res->start = address.address.minimum;
  96		res->end = address.address.minimum + address.address.address_length - 1;
  97	}
  98
  99	return AE_OK;
 100}
 101
 102static acpi_status try_get_root_bridge_busnr(acpi_handle handle,
 103					     struct resource *res)
 104{
 105	acpi_status status;
 106
 107	res->start = -1;
 108	status =
 109	    acpi_walk_resources(handle, METHOD_NAME__CRS,
 110				get_root_bridge_busnr_callback, res);
 111	if (ACPI_FAILURE(status))
 112		return status;
 113	if (res->start == -1)
 114		return AE_ERROR;
 115	return AE_OK;
 116}
 117
 118struct pci_osc_bit_struct {
 119	u32 bit;
 120	char *desc;
 121};
 122
 123static struct pci_osc_bit_struct pci_osc_support_bit[] = {
 124	{ OSC_PCI_EXT_CONFIG_SUPPORT, "ExtendedConfig" },
 125	{ OSC_PCI_ASPM_SUPPORT, "ASPM" },
 126	{ OSC_PCI_CLOCK_PM_SUPPORT, "ClockPM" },
 127	{ OSC_PCI_SEGMENT_GROUPS_SUPPORT, "Segments" },
 128	{ OSC_PCI_MSI_SUPPORT, "MSI" },
 129	{ OSC_PCI_EDR_SUPPORT, "EDR" },
 130	{ OSC_PCI_HPX_TYPE_3_SUPPORT, "HPX-Type3" },
 131};
 132
 133static struct pci_osc_bit_struct pci_osc_control_bit[] = {
 134	{ OSC_PCI_EXPRESS_NATIVE_HP_CONTROL, "PCIeHotplug" },
 135	{ OSC_PCI_SHPC_NATIVE_HP_CONTROL, "SHPCHotplug" },
 136	{ OSC_PCI_EXPRESS_PME_CONTROL, "PME" },
 137	{ OSC_PCI_EXPRESS_AER_CONTROL, "AER" },
 138	{ OSC_PCI_EXPRESS_CAPABILITY_CONTROL, "PCIeCapability" },
 139	{ OSC_PCI_EXPRESS_LTR_CONTROL, "LTR" },
 140	{ OSC_PCI_EXPRESS_DPC_CONTROL, "DPC" },
 141};
 142
 143static struct pci_osc_bit_struct cxl_osc_support_bit[] = {
 144	{ OSC_CXL_1_1_PORT_REG_ACCESS_SUPPORT, "CXL11PortRegAccess" },
 145	{ OSC_CXL_2_0_PORT_DEV_REG_ACCESS_SUPPORT, "CXL20PortDevRegAccess" },
 146	{ OSC_CXL_PROTOCOL_ERR_REPORTING_SUPPORT, "CXLProtocolErrorReporting" },
 147	{ OSC_CXL_NATIVE_HP_SUPPORT, "CXLNativeHotPlug" },
 148};
 149
 150static struct pci_osc_bit_struct cxl_osc_control_bit[] = {
 151	{ OSC_CXL_ERROR_REPORTING_CONTROL, "CXLMemErrorReporting" },
 152};
 153
 154static void decode_osc_bits(struct acpi_pci_root *root, char *msg, u32 word,
 155			    struct pci_osc_bit_struct *table, int size)
 156{
 157	char buf[80];
 158	int i, len = 0;
 159	struct pci_osc_bit_struct *entry;
 160
 161	buf[0] = '\0';
 162	for (i = 0, entry = table; i < size; i++, entry++)
 163		if (word & entry->bit)
 164			len += scnprintf(buf + len, sizeof(buf) - len, "%s%s",
 165					len ? " " : "", entry->desc);
 166
 167	dev_info(&root->device->dev, "_OSC: %s [%s]\n", msg, buf);
 168}
 169
 170static void decode_osc_support(struct acpi_pci_root *root, char *msg, u32 word)
 171{
 172	decode_osc_bits(root, msg, word, pci_osc_support_bit,
 173			ARRAY_SIZE(pci_osc_support_bit));
 174}
 175
 176static void decode_osc_control(struct acpi_pci_root *root, char *msg, u32 word)
 177{
 178	decode_osc_bits(root, msg, word, pci_osc_control_bit,
 179			ARRAY_SIZE(pci_osc_control_bit));
 180}
 181
 182static void decode_cxl_osc_support(struct acpi_pci_root *root, char *msg, u32 word)
 183{
 184	decode_osc_bits(root, msg, word, cxl_osc_support_bit,
 185			ARRAY_SIZE(cxl_osc_support_bit));
 186}
 187
 188static void decode_cxl_osc_control(struct acpi_pci_root *root, char *msg, u32 word)
 189{
 190	decode_osc_bits(root, msg, word, cxl_osc_control_bit,
 191			ARRAY_SIZE(cxl_osc_control_bit));
 192}
 193
 194static inline bool is_pcie(struct acpi_pci_root *root)
 195{
 196	return root->bridge_type == ACPI_BRIDGE_TYPE_PCIE;
 197}
 198
 199static inline bool is_cxl(struct acpi_pci_root *root)
 200{
 201	return root->bridge_type == ACPI_BRIDGE_TYPE_CXL;
 202}
 203
 204static u8 pci_osc_uuid_str[] = "33DB4D5B-1FF7-401C-9657-7441C03DD766";
 205static u8 cxl_osc_uuid_str[] = "68F2D50B-C469-4d8A-BD3D-941A103FD3FC";
 206
 207static char *to_uuid(struct acpi_pci_root *root)
 208{
 209	if (is_cxl(root))
 210		return cxl_osc_uuid_str;
 211	return pci_osc_uuid_str;
 212}
 213
 214static int cap_length(struct acpi_pci_root *root)
 215{
 216	if (is_cxl(root))
 217		return sizeof(u32) * OSC_CXL_CAPABILITY_DWORDS;
 218	return sizeof(u32) * OSC_PCI_CAPABILITY_DWORDS;
 219}
 220
 221static acpi_status acpi_pci_run_osc(struct acpi_pci_root *root,
 222				    const u32 *capbuf, u32 *pci_control,
 223				    u32 *cxl_control)
 224{
 225	struct acpi_osc_context context = {
 226		.uuid_str = to_uuid(root),
 227		.rev = 1,
 228		.cap.length = cap_length(root),
 229		.cap.pointer = (void *)capbuf,
 230	};
 231	acpi_status status;
 232
 233	status = acpi_run_osc(root->device->handle, &context);
 234	if (ACPI_SUCCESS(status)) {
 235		*pci_control = acpi_osc_ctx_get_pci_control(&context);
 236		if (is_cxl(root))
 237			*cxl_control = acpi_osc_ctx_get_cxl_control(&context);
 238		kfree(context.ret.pointer);
 239	}
 240	return status;
 241}
 242
 243static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root, u32 support,
 244				      u32 *control, u32 cxl_support,
 245				      u32 *cxl_control)
 246{
 247	acpi_status status;
 248	u32 pci_result, cxl_result, capbuf[OSC_CXL_CAPABILITY_DWORDS];
 249
 250	support |= root->osc_support_set;
 251
 252	capbuf[OSC_QUERY_DWORD] = OSC_QUERY_ENABLE;
 253	capbuf[OSC_SUPPORT_DWORD] = support;
 254	capbuf[OSC_CONTROL_DWORD] = *control | root->osc_control_set;
 255
 256	if (is_cxl(root)) {
 257		cxl_support |= root->osc_ext_support_set;
 258		capbuf[OSC_EXT_SUPPORT_DWORD] = cxl_support;
 259		capbuf[OSC_EXT_CONTROL_DWORD] = *cxl_control | root->osc_ext_control_set;
 260	}
 261
 262retry:
 263	status = acpi_pci_run_osc(root, capbuf, &pci_result, &cxl_result);
 264	if (ACPI_SUCCESS(status)) {
 265		root->osc_support_set = support;
 266		*control = pci_result;
 267		if (is_cxl(root)) {
 268			root->osc_ext_support_set = cxl_support;
 269			*cxl_control = cxl_result;
 270		}
 271	} else if (is_cxl(root)) {
 272		/*
 273		 * CXL _OSC is optional on CXL 1.1 hosts. Fall back to PCIe _OSC
 274		 * upon any failure using CXL _OSC.
 275		 */
 276		root->bridge_type = ACPI_BRIDGE_TYPE_PCIE;
 277		goto retry;
 278	}
 279	return status;
 280}
 281
 282struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle)
 283{
 284	struct acpi_device *device = acpi_fetch_acpi_dev(handle);
 285	struct acpi_pci_root *root;
 286
 287	if (!device || acpi_match_device_ids(device, root_device_ids))
 288		return NULL;
 289
 290	root = acpi_driver_data(device);
 291
 292	return root;
 293}
 294EXPORT_SYMBOL_GPL(acpi_pci_find_root);
 295
 296struct acpi_handle_node {
 297	struct list_head node;
 298	acpi_handle handle;
 299};
 300
 301/**
 302 * acpi_get_pci_dev - convert ACPI CA handle to struct pci_dev
 303 * @handle: the handle in question
 304 *
 305 * Given an ACPI CA handle, the desired PCI device is located in the
 306 * list of PCI devices.
 307 *
 308 * If the device is found, its reference count is increased and this
 309 * function returns a pointer to its data structure.  The caller must
 310 * decrement the reference count by calling pci_dev_put().
 311 * If no device is found, %NULL is returned.
 312 */
 313struct pci_dev *acpi_get_pci_dev(acpi_handle handle)
 314{
 315	struct acpi_device *adev = acpi_fetch_acpi_dev(handle);
 316	struct acpi_device_physical_node *pn;
 317	struct pci_dev *pci_dev = NULL;
 318
 319	if (!adev)
 320		return NULL;
 321
 322	mutex_lock(&adev->physical_node_lock);
 323
 324	list_for_each_entry(pn, &adev->physical_node_list, node) {
 325		if (dev_is_pci(pn->dev)) {
 326			get_device(pn->dev);
 327			pci_dev = to_pci_dev(pn->dev);
 328			break;
 329		}
 330	}
 331
 332	mutex_unlock(&adev->physical_node_lock);
 333
 334	return pci_dev;
 335}
 336EXPORT_SYMBOL_GPL(acpi_get_pci_dev);
 337
 338/**
 339 * acpi_pci_osc_control_set - Request control of PCI root _OSC features.
 340 * @handle: ACPI handle of a PCI root bridge (or PCIe Root Complex).
 341 * @mask: Mask of _OSC bits to request control of, place to store control mask.
 342 * @support: _OSC supported capability.
 343 * @cxl_mask: Mask of CXL _OSC control bits, place to store control mask.
 344 * @cxl_support: CXL _OSC supported capability.
 345 *
 346 * Run _OSC query for @mask and if that is successful, compare the returned
 347 * mask of control bits with @req.  If all of the @req bits are set in the
 348 * returned mask, run _OSC request for it.
 349 *
 350 * The variable at the @mask address may be modified regardless of whether or
 351 * not the function returns success.  On success it will contain the mask of
 352 * _OSC bits the BIOS has granted control of, but its contents are meaningless
 353 * on failure.
 354 **/
 355static acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 *mask,
 356					    u32 support, u32 *cxl_mask,
 357					    u32 cxl_support)
 358{
 359	u32 req = OSC_PCI_EXPRESS_CAPABILITY_CONTROL;
 360	struct acpi_pci_root *root;
 361	acpi_status status;
 362	u32 ctrl, cxl_ctrl = 0, capbuf[OSC_CXL_CAPABILITY_DWORDS];
 363
 364	if (!mask)
 365		return AE_BAD_PARAMETER;
 366
 367	root = acpi_pci_find_root(handle);
 368	if (!root)
 369		return AE_NOT_EXIST;
 370
 371	ctrl   = *mask;
 372	*mask |= root->osc_control_set;
 373
 374	if (is_cxl(root)) {
 375		cxl_ctrl = *cxl_mask;
 376		*cxl_mask |= root->osc_ext_control_set;
 377	}
 378
 379	/* Need to check the available controls bits before requesting them. */
 380	do {
 381		u32 pci_missing = 0, cxl_missing = 0;
 382
 383		status = acpi_pci_query_osc(root, support, mask, cxl_support,
 384					    cxl_mask);
 385		if (ACPI_FAILURE(status))
 386			return status;
 387		if (is_cxl(root)) {
 388			if (ctrl == *mask && cxl_ctrl == *cxl_mask)
 389				break;
 390			pci_missing = ctrl & ~(*mask);
 391			cxl_missing = cxl_ctrl & ~(*cxl_mask);
 392		} else {
 393			if (ctrl == *mask)
 394				break;
 395			pci_missing = ctrl & ~(*mask);
 396		}
 397		if (pci_missing)
 398			decode_osc_control(root, "platform does not support",
 399					   pci_missing);
 400		if (cxl_missing)
 401			decode_cxl_osc_control(root, "CXL platform does not support",
 402					   cxl_missing);
 403		ctrl = *mask;
 404		cxl_ctrl = *cxl_mask;
 405	} while (*mask || *cxl_mask);
 406
 407	/* No need to request _OSC if the control was already granted. */
 408	if ((root->osc_control_set & ctrl) == ctrl &&
 409	    (root->osc_ext_control_set & cxl_ctrl) == cxl_ctrl)
 410		return AE_OK;
 411
 412	if ((ctrl & req) != req) {
 413		decode_osc_control(root, "not requesting control; platform does not support",
 414				   req & ~(ctrl));
 415		return AE_SUPPORT;
 416	}
 417
 418	capbuf[OSC_QUERY_DWORD] = 0;
 419	capbuf[OSC_SUPPORT_DWORD] = root->osc_support_set;
 420	capbuf[OSC_CONTROL_DWORD] = ctrl;
 421	if (is_cxl(root)) {
 422		capbuf[OSC_EXT_SUPPORT_DWORD] = root->osc_ext_support_set;
 423		capbuf[OSC_EXT_CONTROL_DWORD] = cxl_ctrl;
 424	}
 425
 426	status = acpi_pci_run_osc(root, capbuf, mask, cxl_mask);
 427	if (ACPI_FAILURE(status))
 428		return status;
 429
 430	root->osc_control_set = *mask;
 431	root->osc_ext_control_set = *cxl_mask;
 432	return AE_OK;
 433}
 434
 435static u32 calculate_support(void)
 436{
 437	u32 support;
 438
 439	/*
 440	 * All supported architectures that use ACPI have support for
 441	 * PCI domains, so we indicate this in _OSC support capabilities.
 442	 */
 443	support = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
 444	support |= OSC_PCI_HPX_TYPE_3_SUPPORT;
 445	if (pci_ext_cfg_avail())
 446		support |= OSC_PCI_EXT_CONFIG_SUPPORT;
 447	if (pcie_aspm_support_enabled())
 448		support |= OSC_PCI_ASPM_SUPPORT | OSC_PCI_CLOCK_PM_SUPPORT;
 449	if (pci_msi_enabled())
 450		support |= OSC_PCI_MSI_SUPPORT;
 451	if (IS_ENABLED(CONFIG_PCIE_EDR))
 452		support |= OSC_PCI_EDR_SUPPORT;
 453
 454	return support;
 455}
 456
 457/*
 458 * Background on hotplug support, and making it depend on only
 459 * CONFIG_HOTPLUG_PCI_PCIE vs. also considering CONFIG_MEMORY_HOTPLUG:
 460 *
 461 * CONFIG_ACPI_HOTPLUG_MEMORY does depend on CONFIG_MEMORY_HOTPLUG, but
 462 * there is no existing _OSC for memory hotplug support. The reason is that
 463 * ACPI memory hotplug requires the OS to acknowledge / coordinate with
 464 * memory plug events via a scan handler. On the CXL side the equivalent
 465 * would be if Linux supported the Mechanical Retention Lock [1], or
 466 * otherwise had some coordination for the driver of a PCI device
 467 * undergoing hotplug to be consulted on whether the hotplug should
 468 * proceed or not.
 469 *
 470 * The concern is that if Linux says no to supporting CXL hotplug then
 471 * the BIOS may say no to giving the OS hotplug control of any other PCIe
 472 * device. So the question here is not whether hotplug is enabled, it's
 473 * whether it is handled natively by the at all OS, and if
 474 * CONFIG_HOTPLUG_PCI_PCIE is enabled then the answer is "yes".
 475 *
 476 * Otherwise, the plan for CXL coordinated remove, since the kernel does
 477 * not support blocking hotplug, is to require the memory device to be
 478 * disabled before hotplug is attempted. When CONFIG_MEMORY_HOTPLUG is
 479 * disabled that step will fail and the remove attempt cancelled by the
 480 * user. If that is not honored and the card is removed anyway then it
 481 * does not matter if CONFIG_MEMORY_HOTPLUG is enabled or not, it will
 482 * cause a crash and other badness.
 483 *
 484 * Therefore, just say yes to CXL hotplug and require removal to
 485 * be coordinated by userspace unless and until the kernel grows better
 486 * mechanisms for doing "managed" removal of devices in consultation with
 487 * the driver.
 488 *
 489 * [1]: https://lore.kernel.org/all/20201122014203.4706-1-ashok.raj@intel.com/
 490 */
 491static u32 calculate_cxl_support(void)
 492{
 493	u32 support;
 494
 495	support = OSC_CXL_2_0_PORT_DEV_REG_ACCESS_SUPPORT;
 496	support |= OSC_CXL_1_1_PORT_REG_ACCESS_SUPPORT;
 497	if (pci_aer_available())
 498		support |= OSC_CXL_PROTOCOL_ERR_REPORTING_SUPPORT;
 499	if (IS_ENABLED(CONFIG_HOTPLUG_PCI_PCIE))
 500		support |= OSC_CXL_NATIVE_HP_SUPPORT;
 501
 502	return support;
 503}
 504
 505static u32 calculate_control(void)
 506{
 507	u32 control;
 508
 509	control = OSC_PCI_EXPRESS_CAPABILITY_CONTROL
 510		| OSC_PCI_EXPRESS_PME_CONTROL;
 511
 512	if (IS_ENABLED(CONFIG_PCIEASPM))
 513		control |= OSC_PCI_EXPRESS_LTR_CONTROL;
 514
 515	if (IS_ENABLED(CONFIG_HOTPLUG_PCI_PCIE))
 516		control |= OSC_PCI_EXPRESS_NATIVE_HP_CONTROL;
 517
 518	if (IS_ENABLED(CONFIG_HOTPLUG_PCI_SHPC))
 519		control |= OSC_PCI_SHPC_NATIVE_HP_CONTROL;
 520
 521	if (pci_aer_available())
 522		control |= OSC_PCI_EXPRESS_AER_CONTROL;
 523
 524	/*
 525	 * Per the Downstream Port Containment Related Enhancements ECN to
 526	 * the PCI Firmware Spec, r3.2, sec 4.5.1, table 4-5,
 527	 * OSC_PCI_EXPRESS_DPC_CONTROL indicates the OS supports both DPC
 528	 * and EDR.
 529	 */
 530	if (IS_ENABLED(CONFIG_PCIE_DPC) && IS_ENABLED(CONFIG_PCIE_EDR))
 531		control |= OSC_PCI_EXPRESS_DPC_CONTROL;
 532
 533	return control;
 534}
 535
 536static u32 calculate_cxl_control(void)
 537{
 538	u32 control = 0;
 539
 540	if (IS_ENABLED(CONFIG_MEMORY_FAILURE))
 541		control |= OSC_CXL_ERROR_REPORTING_CONTROL;
 542
 543	return control;
 544}
 545
 546static bool os_control_query_checks(struct acpi_pci_root *root, u32 support)
 547{
 548	struct acpi_device *device = root->device;
 549
 550	if (pcie_ports_disabled) {
 551		dev_info(&device->dev, "PCIe port services disabled; not requesting _OSC control\n");
 552		return false;
 553	}
 554
 555	if ((support & ACPI_PCIE_REQ_SUPPORT) != ACPI_PCIE_REQ_SUPPORT) {
 556		decode_osc_support(root, "not requesting OS control; OS requires",
 557				   ACPI_PCIE_REQ_SUPPORT);
 558		return false;
 559	}
 560
 561	return true;
 562}
 563
 564static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm)
 565{
 566	u32 support, control = 0, requested = 0;
 567	u32 cxl_support = 0, cxl_control = 0, cxl_requested = 0;
 568	acpi_status status;
 569	struct acpi_device *device = root->device;
 570	acpi_handle handle = device->handle;
 571
 572	/*
 573	 * Apple always return failure on _OSC calls when _OSI("Darwin") has
 574	 * been called successfully. We know the feature set supported by the
 575	 * platform, so avoid calling _OSC at all
 576	 */
 577	if (x86_apple_machine) {
 578		root->osc_control_set = ~OSC_PCI_EXPRESS_PME_CONTROL;
 579		decode_osc_control(root, "OS assumes control of",
 580				   root->osc_control_set);
 581		return;
 582	}
 583
 584	support = calculate_support();
 585
 586	decode_osc_support(root, "OS supports", support);
 587
 588	if (os_control_query_checks(root, support))
 589		requested = control = calculate_control();
 590
 591	if (is_cxl(root)) {
 592		cxl_support = calculate_cxl_support();
 593		decode_cxl_osc_support(root, "OS supports", cxl_support);
 594		cxl_requested = cxl_control = calculate_cxl_control();
 595	}
 596
 597	status = acpi_pci_osc_control_set(handle, &control, support,
 598					  &cxl_control, cxl_support);
 599	if (ACPI_SUCCESS(status)) {
 600		if (control)
 601			decode_osc_control(root, "OS now controls", control);
 602		if (cxl_control)
 603			decode_cxl_osc_control(root, "OS now controls",
 604					   cxl_control);
 605
 606		if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) {
 607			/*
 608			 * We have ASPM control, but the FADT indicates that
 609			 * it's unsupported. Leave existing configuration
 610			 * intact and prevent the OS from touching it.
 611			 */
 612			dev_info(&device->dev, "FADT indicates ASPM is unsupported, using BIOS configuration\n");
 613			*no_aspm = 1;
 614		}
 615	} else {
 616		/*
 617		 * We want to disable ASPM here, but aspm_disabled
 618		 * needs to remain in its state from boot so that we
 619		 * properly handle PCIe 1.1 devices.  So we set this
 620		 * flag here, to defer the action until after the ACPI
 621		 * root scan.
 622		 */
 623		*no_aspm = 1;
 624
 625		/* _OSC is optional for PCI host bridges */
 626		if (status == AE_NOT_FOUND && !is_pcie(root))
 627			return;
 628
 629		if (control) {
 630			decode_osc_control(root, "OS requested", requested);
 631			decode_osc_control(root, "platform willing to grant", control);
 632		}
 633		if (cxl_control) {
 634			decode_cxl_osc_control(root, "OS requested", cxl_requested);
 635			decode_cxl_osc_control(root, "platform willing to grant",
 636					   cxl_control);
 637		}
 638
 639		dev_info(&device->dev, "_OSC: platform retains control of PCIe features (%s)\n",
 640			 acpi_format_exception(status));
 641	}
 642}
 643
 644static int acpi_pci_root_add(struct acpi_device *device,
 645			     const struct acpi_device_id *not_used)
 646{
 647	unsigned long long segment, bus;
 648	acpi_status status;
 649	int result;
 650	struct acpi_pci_root *root;
 651	acpi_handle handle = device->handle;
 652	int no_aspm = 0;
 653	bool hotadd = system_state == SYSTEM_RUNNING;
 654	const char *acpi_hid;
 655
 656	root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
 657	if (!root)
 658		return -ENOMEM;
 659
 660	segment = 0;
 661	status = acpi_evaluate_integer(handle, METHOD_NAME__SEG, NULL,
 662				       &segment);
 663	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 664		dev_err(&device->dev,  "can't evaluate _SEG\n");
 665		result = -ENODEV;
 666		goto end;
 667	}
 668
 669	/* Check _CRS first, then _BBN.  If no _BBN, default to zero. */
 670	root->secondary.flags = IORESOURCE_BUS;
 671	status = try_get_root_bridge_busnr(handle, &root->secondary);
 672	if (ACPI_FAILURE(status)) {
 673		/*
 674		 * We need both the start and end of the downstream bus range
 675		 * to interpret _CBA (MMCONFIG base address), so it really is
 676		 * supposed to be in _CRS.  If we don't find it there, all we
 677		 * can do is assume [_BBN-0xFF] or [0-0xFF].
 678		 */
 679		root->secondary.end = 0xFF;
 680		dev_warn(&device->dev,
 681			 FW_BUG "no secondary bus range in _CRS\n");
 682		status = acpi_evaluate_integer(handle, METHOD_NAME__BBN,
 683					       NULL, &bus);
 684		if (ACPI_SUCCESS(status))
 685			root->secondary.start = bus;
 686		else if (status == AE_NOT_FOUND)
 687			root->secondary.start = 0;
 688		else {
 689			dev_err(&device->dev, "can't evaluate _BBN\n");
 690			result = -ENODEV;
 691			goto end;
 692		}
 693	}
 694
 695	root->device = device;
 696	root->segment = segment & 0xFFFF;
 697	strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
 698	strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
 699	device->driver_data = root;
 700
 701	if (hotadd && dmar_device_add(handle)) {
 702		result = -ENXIO;
 703		goto end;
 704	}
 705
 706	pr_info("%s [%s] (domain %04x %pR)\n",
 707	       acpi_device_name(device), acpi_device_bid(device),
 708	       root->segment, &root->secondary);
 709
 710	root->mcfg_addr = acpi_pci_root_get_mcfg_addr(handle);
 711
 712	acpi_hid = acpi_device_hid(root->device);
 713	if (strcmp(acpi_hid, "PNP0A08") == 0)
 714		root->bridge_type = ACPI_BRIDGE_TYPE_PCIE;
 715	else if (strcmp(acpi_hid, "ACPI0016") == 0)
 716		root->bridge_type = ACPI_BRIDGE_TYPE_CXL;
 717	else
 718		dev_dbg(&device->dev, "Assuming non-PCIe host bridge\n");
 719
 720	negotiate_os_control(root, &no_aspm);
 721
 722	/*
 723	 * TBD: Need PCI interface for enumeration/configuration of roots.
 724	 */
 725
 726	/*
 727	 * Scan the Root Bridge
 728	 * --------------------
 729	 * Must do this prior to any attempt to bind the root device, as the
 730	 * PCI namespace does not get created until this call is made (and
 731	 * thus the root bridge's pci_dev does not exist).
 732	 */
 733	root->bus = pci_acpi_scan_root(root);
 734	if (!root->bus) {
 735		dev_err(&device->dev,
 736			"Bus %04x:%02x not present in PCI namespace\n",
 737			root->segment, (unsigned int)root->secondary.start);
 738		device->driver_data = NULL;
 739		result = -ENODEV;
 740		goto remove_dmar;
 741	}
 742
 743	if (no_aspm)
 744		pcie_no_aspm();
 745
 746	pci_acpi_add_bus_pm_notifier(device);
 747	device_set_wakeup_capable(root->bus->bridge, device->wakeup.flags.valid);
 748
 749	if (hotadd) {
 750		pcibios_resource_survey_bus(root->bus);
 751		pci_assign_unassigned_root_bus_resources(root->bus);
 752		/*
 753		 * This is only called for the hotadd case. For the boot-time
 754		 * case, we need to wait until after PCI initialization in
 755		 * order to deal with IOAPICs mapped in on a PCI BAR.
 756		 *
 757		 * This is currently x86-specific, because acpi_ioapic_add()
 758		 * is an empty function without CONFIG_ACPI_HOTPLUG_IOAPIC.
 759		 * And CONFIG_ACPI_HOTPLUG_IOAPIC depends on CONFIG_X86_IO_APIC
 760		 * (see drivers/acpi/Kconfig).
 761		 */
 762		acpi_ioapic_add(root->device->handle);
 763	}
 764
 765	pci_lock_rescan_remove();
 766	pci_bus_add_devices(root->bus);
 767	pci_unlock_rescan_remove();
 768	return 1;
 769
 770remove_dmar:
 771	if (hotadd)
 772		dmar_device_remove(handle);
 773end:
 774	kfree(root);
 775	return result;
 776}
 777
 778static void acpi_pci_root_remove(struct acpi_device *device)
 779{
 780	struct acpi_pci_root *root = acpi_driver_data(device);
 781
 782	pci_lock_rescan_remove();
 783
 784	pci_stop_root_bus(root->bus);
 785
 786	pci_ioapic_remove(root);
 787	device_set_wakeup_capable(root->bus->bridge, false);
 788	pci_acpi_remove_bus_pm_notifier(device);
 789
 790	pci_remove_root_bus(root->bus);
 791	WARN_ON(acpi_ioapic_remove(root));
 792
 793	dmar_device_remove(device->handle);
 794
 795	pci_unlock_rescan_remove();
 796
 797	kfree(root);
 798}
 799
 800/*
 801 * Following code to support acpi_pci_root_create() is copied from
 802 * arch/x86/pci/acpi.c and modified so it could be reused by x86, IA64
 803 * and ARM64.
 804 */
 805static void acpi_pci_root_validate_resources(struct device *dev,
 806					     struct list_head *resources,
 807					     unsigned long type)
 808{
 809	LIST_HEAD(list);
 810	struct resource *res1, *res2, *root = NULL;
 811	struct resource_entry *tmp, *entry, *entry2;
 812
 813	BUG_ON((type & (IORESOURCE_MEM | IORESOURCE_IO)) == 0);
 814	root = (type & IORESOURCE_MEM) ? &iomem_resource : &ioport_resource;
 815
 816	list_splice_init(resources, &list);
 817	resource_list_for_each_entry_safe(entry, tmp, &list) {
 818		bool free = false;
 819		resource_size_t end;
 820
 821		res1 = entry->res;
 822		if (!(res1->flags & type))
 823			goto next;
 824
 825		/* Exclude non-addressable range or non-addressable portion */
 826		end = min(res1->end, root->end);
 827		if (end <= res1->start) {
 828			dev_info(dev, "host bridge window %pR (ignored, not CPU addressable)\n",
 829				 res1);
 830			free = true;
 831			goto next;
 832		} else if (res1->end != end) {
 833			dev_info(dev, "host bridge window %pR ([%#llx-%#llx] ignored, not CPU addressable)\n",
 834				 res1, (unsigned long long)end + 1,
 835				 (unsigned long long)res1->end);
 836			res1->end = end;
 837		}
 838
 839		resource_list_for_each_entry(entry2, resources) {
 840			res2 = entry2->res;
 841			if (!(res2->flags & type))
 842				continue;
 843
 844			/*
 845			 * I don't like throwing away windows because then
 846			 * our resources no longer match the ACPI _CRS, but
 847			 * the kernel resource tree doesn't allow overlaps.
 848			 */
 849			if (resource_union(res1, res2, res2)) {
 850				dev_info(dev, "host bridge window expanded to %pR; %pR ignored\n",
 851					 res2, res1);
 852				free = true;
 853				goto next;
 854			}
 855		}
 856
 857next:
 858		resource_list_del(entry);
 859		if (free)
 860			resource_list_free_entry(entry);
 861		else
 862			resource_list_add_tail(entry, resources);
 863	}
 864}
 865
 866static void acpi_pci_root_remap_iospace(struct fwnode_handle *fwnode,
 867			struct resource_entry *entry)
 868{
 869#ifdef PCI_IOBASE
 870	struct resource *res = entry->res;
 871	resource_size_t cpu_addr = res->start;
 872	resource_size_t pci_addr = cpu_addr - entry->offset;
 873	resource_size_t length = resource_size(res);
 874	unsigned long port;
 875
 876	if (pci_register_io_range(fwnode, cpu_addr, length))
 877		goto err;
 878
 879	port = pci_address_to_pio(cpu_addr);
 880	if (port == (unsigned long)-1)
 881		goto err;
 882
 883	res->start = port;
 884	res->end = port + length - 1;
 885	entry->offset = port - pci_addr;
 886
 887	if (pci_remap_iospace(res, cpu_addr) < 0)
 888		goto err;
 889
 890	pr_info("Remapped I/O %pa to %pR\n", &cpu_addr, res);
 891	return;
 892err:
 893	res->flags |= IORESOURCE_DISABLED;
 894#endif
 895}
 896
 897int acpi_pci_probe_root_resources(struct acpi_pci_root_info *info)
 898{
 899	int ret;
 900	struct list_head *list = &info->resources;
 901	struct acpi_device *device = info->bridge;
 902	struct resource_entry *entry, *tmp;
 903	unsigned long flags;
 904
 905	flags = IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_MEM_8AND16BIT;
 906	ret = acpi_dev_get_resources(device, list,
 907				     acpi_dev_filter_resource_type_cb,
 908				     (void *)flags);
 909	if (ret < 0)
 910		dev_warn(&device->dev,
 911			 "failed to parse _CRS method, error code %d\n", ret);
 912	else if (ret == 0)
 913		dev_dbg(&device->dev,
 914			"no IO and memory resources present in _CRS\n");
 915	else {
 916		resource_list_for_each_entry_safe(entry, tmp, list) {
 917			if (entry->res->flags & IORESOURCE_IO)
 918				acpi_pci_root_remap_iospace(&device->fwnode,
 919						entry);
 920
 921			if (entry->res->flags & IORESOURCE_DISABLED)
 922				resource_list_destroy_entry(entry);
 923			else
 924				entry->res->name = info->name;
 925		}
 926		acpi_pci_root_validate_resources(&device->dev, list,
 927						 IORESOURCE_MEM);
 928		acpi_pci_root_validate_resources(&device->dev, list,
 929						 IORESOURCE_IO);
 930	}
 931
 932	return ret;
 933}
 934
 935static void pci_acpi_root_add_resources(struct acpi_pci_root_info *info)
 936{
 937	struct resource_entry *entry, *tmp;
 938	struct resource *res, *conflict, *root = NULL;
 939
 940	resource_list_for_each_entry_safe(entry, tmp, &info->resources) {
 941		res = entry->res;
 942		if (res->flags & IORESOURCE_MEM)
 943			root = &iomem_resource;
 944		else if (res->flags & IORESOURCE_IO)
 945			root = &ioport_resource;
 946		else
 947			continue;
 948
 949		/*
 950		 * Some legacy x86 host bridge drivers use iomem_resource and
 951		 * ioport_resource as default resource pool, skip it.
 952		 */
 953		if (res == root)
 954			continue;
 955
 956		conflict = insert_resource_conflict(root, res);
 957		if (conflict) {
 958			dev_info(&info->bridge->dev,
 959				 "ignoring host bridge window %pR (conflicts with %s %pR)\n",
 960				 res, conflict->name, conflict);
 961			resource_list_destroy_entry(entry);
 962		}
 963	}
 964}
 965
 966static void __acpi_pci_root_release_info(struct acpi_pci_root_info *info)
 967{
 968	struct resource *res;
 969	struct resource_entry *entry, *tmp;
 970
 971	if (!info)
 972		return;
 973
 974	resource_list_for_each_entry_safe(entry, tmp, &info->resources) {
 975		res = entry->res;
 976		if (res->parent &&
 977		    (res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
 978			release_resource(res);
 979		resource_list_destroy_entry(entry);
 980	}
 981
 982	info->ops->release_info(info);
 983}
 984
 985static void acpi_pci_root_release_info(struct pci_host_bridge *bridge)
 986{
 987	struct resource *res;
 988	struct resource_entry *entry;
 989
 990	resource_list_for_each_entry(entry, &bridge->windows) {
 991		res = entry->res;
 992		if (res->flags & IORESOURCE_IO)
 993			pci_unmap_iospace(res);
 994		if (res->parent &&
 995		    (res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
 996			release_resource(res);
 997	}
 998	__acpi_pci_root_release_info(bridge->release_data);
 999}
1000
1001struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root,
1002				     struct acpi_pci_root_ops *ops,
1003				     struct acpi_pci_root_info *info,
1004				     void *sysdata)
1005{
1006	int ret, busnum = root->secondary.start;
1007	struct acpi_device *device = root->device;
1008	int node = acpi_get_node(device->handle);
1009	struct pci_bus *bus;
1010	struct pci_host_bridge *host_bridge;
1011	union acpi_object *obj;
1012
1013	info->root = root;
1014	info->bridge = device;
1015	info->ops = ops;
1016	INIT_LIST_HEAD(&info->resources);
1017	snprintf(info->name, sizeof(info->name), "PCI Bus %04x:%02x",
1018		 root->segment, busnum);
1019
1020	if (ops->init_info && ops->init_info(info))
1021		goto out_release_info;
1022	if (ops->prepare_resources)
1023		ret = ops->prepare_resources(info);
1024	else
1025		ret = acpi_pci_probe_root_resources(info);
1026	if (ret < 0)
1027		goto out_release_info;
1028
1029	pci_acpi_root_add_resources(info);
1030	pci_add_resource(&info->resources, &root->secondary);
1031	bus = pci_create_root_bus(NULL, busnum, ops->pci_ops,
1032				  sysdata, &info->resources);
1033	if (!bus)
1034		goto out_release_info;
1035
1036	host_bridge = to_pci_host_bridge(bus->bridge);
1037	if (!(root->osc_control_set & OSC_PCI_EXPRESS_NATIVE_HP_CONTROL))
1038		host_bridge->native_pcie_hotplug = 0;
1039	if (!(root->osc_control_set & OSC_PCI_SHPC_NATIVE_HP_CONTROL))
1040		host_bridge->native_shpc_hotplug = 0;
1041	if (!(root->osc_control_set & OSC_PCI_EXPRESS_AER_CONTROL))
1042		host_bridge->native_aer = 0;
1043	if (!(root->osc_control_set & OSC_PCI_EXPRESS_PME_CONTROL))
1044		host_bridge->native_pme = 0;
1045	if (!(root->osc_control_set & OSC_PCI_EXPRESS_LTR_CONTROL))
1046		host_bridge->native_ltr = 0;
1047	if (!(root->osc_control_set & OSC_PCI_EXPRESS_DPC_CONTROL))
1048		host_bridge->native_dpc = 0;
1049
1050	/*
1051	 * Evaluate the "PCI Boot Configuration" _DSM Function.  If it
1052	 * exists and returns 0, we must preserve any PCI resource
1053	 * assignments made by firmware for this host bridge.
1054	 */
1055	obj = acpi_evaluate_dsm(ACPI_HANDLE(bus->bridge), &pci_acpi_dsm_guid, 1,
1056				DSM_PCI_PRESERVE_BOOT_CONFIG, NULL);
1057	if (obj && obj->type == ACPI_TYPE_INTEGER && obj->integer.value == 0)
1058		host_bridge->preserve_config = 1;
1059	ACPI_FREE(obj);
1060
1061	acpi_dev_power_up_children_with_adr(device);
1062
1063	pci_scan_child_bus(bus);
1064	pci_set_host_bridge_release(host_bridge, acpi_pci_root_release_info,
1065				    info);
1066	if (node != NUMA_NO_NODE)
1067		dev_printk(KERN_DEBUG, &bus->dev, "on NUMA node %d\n", node);
1068	return bus;
1069
1070out_release_info:
1071	__acpi_pci_root_release_info(info);
1072	return NULL;
1073}
1074
1075void __init acpi_pci_root_init(void)
1076{
1077	if (acpi_pci_disabled)
1078		return;
1079
1080	pci_acpi_crs_quirks();
1081	acpi_scan_add_handler_with_hotplug(&pci_root_handler, "pci_root");
1082}