drivers/acpi/pci_root.c

   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 #include <linux/kernel.h>
  10 #include <linux/module.h>
  11 #include <linux/init.h>
  12 #include <linux/types.h>
  13 #include <linux/mutex.h>
  14 #include <linux/pm.h>
  15 #include <linux/pm_runtime.h>
  16 #include <linux/pci.h>
  17 #include <linux/pci-acpi.h>
  18 #include <linux/pci-aspm.h>
  19 #include <linux/dmar.h>
  20 #include <linux/acpi.h>
  21 #include <linux/slab.h>
  22 #include <linux/dmi.h>
  23 #include <linux/platform_data/x86/apple.h>
  24 #include <acpi/apei.h>  /* for acpi_hest_init() */
  25
  26 #include "internal.h"
  27
  28 #define _COMPONENT              ACPI_PCI_COMPONENT
  29 ACPI_MODULE_NAME("pci_root");
  30 #define ACPI_PCI_ROOT_CLASS             "pci_bridge"
  31 #define ACPI_PCI_ROOT_DEVICE_NAME       "PCI Root Bridge"
  32 static int acpi_pci_root_add(struct acpi_device *device,
  33                              const struct acpi_device_id *not_used);
  34 static void acpi_pci_root_remove(struct acpi_device *device);
  35
  36 static int acpi_pci_root_scan_dependent(struct acpi_device *adev)
  37 {
  38         acpiphp_check_host_bridge(adev);
  39         return 0;
  40 }
  41
  42 #define ACPI_PCIE_REQ_SUPPORT (OSC_PCI_EXT_CONFIG_SUPPORT \
  43                                 | OSC_PCI_ASPM_SUPPORT \
  44                                 | OSC_PCI_CLOCK_PM_SUPPORT \
  45                                 | OSC_PCI_MSI_SUPPORT)
  46
  47 static const struct acpi_device_id root_device_ids[] = {
  48         {"PNP0A03", 0},
  49         {"", 0},
  50 };
  51
  52 static struct acpi_scan_handler pci_root_handler = {
  53         .ids = root_device_ids,
  54         .attach = acpi_pci_root_add,
  55         .detach = acpi_pci_root_remove,
  56         .hotplug = {
  57                 .enabled = true,
  58                 .scan_dependent = acpi_pci_root_scan_dependent,
  59         },
  60 };
  61
  62 static DEFINE_MUTEX(osc_lock);
  63
  64 /**
  65  * acpi_is_root_bridge - determine whether an ACPI CA node is a PCI root bridge
  66  * @handle - the ACPI CA node in question.
  67  *
  68  * Note: we could make this API take a struct acpi_device * instead, but
  69  * for now, it's more convenient to operate on an acpi_handle.
  70  */
  71 int acpi_is_root_bridge(acpi_handle handle)
  72 {
  73         int ret;
  74         struct acpi_device *device;
  75
  76         ret = acpi_bus_get_device(handle, &device);
  77         if (ret)
  78                 return 0;
  79
  80         ret = acpi_match_device_ids(device, root_device_ids);
  81         if (ret)
  82                 return 0;
  83         else
  84                 return 1;
  85 }
  86 EXPORT_SYMBOL_GPL(acpi_is_root_bridge);
  87
  88 static acpi_status
  89 get_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
  90 {
  91         struct resource *res = data;
  92         struct acpi_resource_address64 address;
  93         acpi_status status;
  94
  95         status = acpi_resource_to_address64(resource, &address);
  96         if (ACPI_FAILURE(status))
  97                 return AE_OK;
  98
  99         if ((address.address.address_length > 0) &&
 100             (address.resource_type == ACPI_BUS_NUMBER_RANGE)) {
 101                 res->start = address.address.minimum;
 102                 res->end = address.address.minimum + address.address.address_length - 1;
 103         }
 104
 105         return AE_OK;
 106 }
 107
 108 static acpi_status try_get_root_bridge_busnr(acpi_handle handle,
 109                                              struct resource *res)
 110 {
 111         acpi_status status;
 112
 113         res->start = -1;
 114         status =
 115             acpi_walk_resources(handle, METHOD_NAME__CRS,
 116                                 get_root_bridge_busnr_callback, res);
 117         if (ACPI_FAILURE(status))
 118                 return status;
 119         if (res->start == -1)
 120                 return AE_ERROR;
 121         return AE_OK;
 122 }
 123
 124 struct pci_osc_bit_struct {
 125         u32 bit;
 126         char *desc;
 127 };
 128
 129 static struct pci_osc_bit_struct pci_osc_support_bit[] = {
 130         { OSC_PCI_EXT_CONFIG_SUPPORT, "ExtendedConfig" },
 131         { OSC_PCI_ASPM_SUPPORT, "ASPM" },
 132         { OSC_PCI_CLOCK_PM_SUPPORT, "ClockPM" },
 133         { OSC_PCI_SEGMENT_GROUPS_SUPPORT, "Segments" },
 134         { OSC_PCI_MSI_SUPPORT, "MSI" },
 135         { OSC_PCI_HPX_TYPE_3_SUPPORT, "HPX-Type3" },
 136 };
 137
 138 static struct pci_osc_bit_struct pci_osc_control_bit[] = {
 139         { OSC_PCI_EXPRESS_NATIVE_HP_CONTROL, "PCIeHotplug" },
 140         { OSC_PCI_SHPC_NATIVE_HP_CONTROL, "SHPCHotplug" },
 141         { OSC_PCI_EXPRESS_PME_CONTROL, "PME" },
 142         { OSC_PCI_EXPRESS_AER_CONTROL, "AER" },
 143         { OSC_PCI_EXPRESS_CAPABILITY_CONTROL, "PCIeCapability" },
 144         { OSC_PCI_EXPRESS_LTR_CONTROL, "LTR" },
 145 };
 146
 147 static void decode_osc_bits(struct acpi_pci_root *root, char *msg, u32 word,
 148                             struct pci_osc_bit_struct *table, int size)
 149 {
 150         char buf[80];
 151         int i, len = 0;
 152         struct pci_osc_bit_struct *entry;
 153
 154         buf[0] = '\0';
 155         for (i = 0, entry = table; i < size; i++, entry++)
 156                 if (word & entry->bit)
 157                         len += snprintf(buf + len, sizeof(buf) - len, "%s%s",
 158                                         len ? " " : "", entry->desc);
 159
 160         dev_info(&root->device->dev, "_OSC: %s [%s]\n", msg, buf);
 161 }
 162
 163 static void decode_osc_support(struct acpi_pci_root *root, char *msg, u32 word)
 164 {
 165         decode_osc_bits(root, msg, word, pci_osc_support_bit,
 166                         ARRAY_SIZE(pci_osc_support_bit));
 167 }
 168
 169 static void decode_osc_control(struct acpi_pci_root *root, char *msg, u32 word)
 170 {
 171         decode_osc_bits(root, msg, word, pci_osc_control_bit,
 172                         ARRAY_SIZE(pci_osc_control_bit));
 173 }
 174
 175 static u8 pci_osc_uuid_str[] = "33DB4D5B-1FF7-401C-9657-7441C03DD766";
 176
 177 static acpi_status acpi_pci_run_osc(acpi_handle handle,
 178                                     const u32 *capbuf, u32 *retval)
 179 {
 180         struct acpi_osc_context context = {
 181                 .uuid_str = pci_osc_uuid_str,
 182                 .rev = 1,
 183                 .cap.length = 12,
 184                 .cap.pointer = (void *)capbuf,
 185         };
 186         acpi_status status;
 187
 188         status = acpi_run_osc(handle, &context);
 189         if (ACPI_SUCCESS(status)) {
 190                 *retval = *((u32 *)(context.ret.pointer + 8));
 191                 kfree(context.ret.pointer);
 192         }
 193         return status;
 194 }
 195
 196 static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root,
 197                                         u32 support,
 198                                         u32 *control)
 199 {
 200         acpi_status status;
 201         u32 result, capbuf[3];
 202
 203         support &= OSC_PCI_SUPPORT_MASKS;
 204         support |= root->osc_support_set;
 205
 206         capbuf[OSC_QUERY_DWORD] = OSC_QUERY_ENABLE;
 207         capbuf[OSC_SUPPORT_DWORD] = support;
 208         if (control) {
 209                 *control &= OSC_PCI_CONTROL_MASKS;
 210                 capbuf[OSC_CONTROL_DWORD] = *control | root->osc_control_set;
 211         } else {
 212                 /* Run _OSC query only with existing controls. */
 213                 capbuf[OSC_CONTROL_DWORD] = root->osc_control_set;
 214         }
 215
 216         status = acpi_pci_run_osc(root->device->handle, capbuf, &result);
 217         if (ACPI_SUCCESS(status)) {
 218                 root->osc_support_set = support;
 219                 if (control)
 220                         *control = result;
 221         }
 222         return status;
 223 }
 224
 225 static acpi_status acpi_pci_osc_support(struct acpi_pci_root *root, u32 flags)
 226 {
 227         acpi_status status;
 228
 229         mutex_lock(&osc_lock);
 230         status = acpi_pci_query_osc(root, flags, NULL);
 231         mutex_unlock(&osc_lock);
 232         return status;
 233 }
 234
 235 struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle)
 236 {
 237         struct acpi_pci_root *root;
 238         struct acpi_device *device;
 239
 240         if (acpi_bus_get_device(handle, &device) ||
 241             acpi_match_device_ids(device, root_device_ids))
 242                 return NULL;
 243
 244         root = acpi_driver_data(device);
 245
 246         return root;
 247 }
 248 EXPORT_SYMBOL_GPL(acpi_pci_find_root);
 249
 250 struct acpi_handle_node {
 251         struct list_head node;
 252         acpi_handle handle;
 253 };
 254
 255 /**
 256  * acpi_get_pci_dev - convert ACPI CA handle to struct pci_dev
 257  * @handle: the handle in question
 258  *
 259  * Given an ACPI CA handle, the desired PCI device is located in the
 260  * list of PCI devices.
 261  *
 262  * If the device is found, its reference count is increased and this
 263  * function returns a pointer to its data structure.  The caller must
 264  * decrement the reference count by calling pci_dev_put().
 265  * If no device is found, %NULL is returned.
 266  */
 267 struct pci_dev *acpi_get_pci_dev(acpi_handle handle)
 268 {
 269         int dev, fn;
 270         unsigned long long adr;
 271         acpi_status status;
 272         acpi_handle phandle;
 273         struct pci_bus *pbus;
 274         struct pci_dev *pdev = NULL;
 275         struct acpi_handle_node *node, *tmp;
 276         struct acpi_pci_root *root;
 277         LIST_HEAD(device_list);
 278
 279         /*
 280          * Walk up the ACPI CA namespace until we reach a PCI root bridge.
 281          */
 282         phandle = handle;
 283         while (!acpi_is_root_bridge(phandle)) {
 284                 node = kzalloc(sizeof(struct acpi_handle_node), GFP_KERNEL);
 285                 if (!node)
 286                         goto out;
 287
 288                 INIT_LIST_HEAD(&node->node);
 289                 node->handle = phandle;
 290                 list_add(&node->node, &device_list);
 291
 292                 status = acpi_get_parent(phandle, &phandle);
 293                 if (ACPI_FAILURE(status))
 294                         goto out;
 295         }
 296
 297         root = acpi_pci_find_root(phandle);
 298         if (!root)
 299                 goto out;
 300
 301         pbus = root->bus;
 302
 303         /*
 304          * Now, walk back down the PCI device tree until we return to our
 305          * original handle. Assumes that everything between the PCI root
 306          * bridge and the device we're looking for must be a P2P bridge.
 307          */
 308         list_for_each_entry(node, &device_list, node) {
 309                 acpi_handle hnd = node->handle;
 310                 status = acpi_evaluate_integer(hnd, "_ADR", NULL, &adr);
 311                 if (ACPI_FAILURE(status))
 312                         goto out;
 313                 dev = (adr >> 16) & 0xffff;
 314                 fn  = adr & 0xffff;
 315
 316                 pdev = pci_get_slot(pbus, PCI_DEVFN(dev, fn));
 317                 if (!pdev || hnd == handle)
 318                         break;
 319
 320                 pbus = pdev->subordinate;
 321                 pci_dev_put(pdev);
 322
 323                 /*
 324                  * This function may be called for a non-PCI device that has a
 325                  * PCI parent (eg. a disk under a PCI SATA controller).  In that
 326                  * case pdev->subordinate will be NULL for the parent.
 327                  */
 328                 if (!pbus) {
 329                         dev_dbg(&pdev->dev, "Not a PCI-to-PCI bridge\n");
 330                         pdev = NULL;
 331                         break;
 332                 }
 333         }
 334 out:
 335         list_for_each_entry_safe(node, tmp, &device_list, node)
 336                 kfree(node);
 337
 338         return pdev;
 339 }
 340 EXPORT_SYMBOL_GPL(acpi_get_pci_dev);
 341
 342 /**
 343  * acpi_pci_osc_control_set - Request control of PCI root _OSC features.
 344  * @handle: ACPI handle of a PCI root bridge (or PCIe Root Complex).
 345  * @mask: Mask of _OSC bits to request control of, place to store control mask.
 346  * @req: Mask of _OSC bits the control of is essential to the caller.
 347  *
 348  * Run _OSC query for @mask and if that is successful, compare the returned
 349  * mask of control bits with @req.  If all of the @req bits are set in the
 350  * returned mask, run _OSC request for it.
 351  *
 352  * The variable at the @mask address may be modified regardless of whether or
 353  * not the function returns success.  On success it will contain the mask of
 354  * _OSC bits the BIOS has granted control of, but its contents are meaningless
 355  * on failure.
 356  **/
 357 acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 *mask, u32 req)
 358 {
 359         struct acpi_pci_root *root;
 360         acpi_status status = AE_OK;
 361         u32 ctrl, capbuf[3];
 362
 363         if (!mask)
 364                 return AE_BAD_PARAMETER;
 365
 366         ctrl = *mask & OSC_PCI_CONTROL_MASKS;
 367         if ((ctrl & req) != req)
 368                 return AE_TYPE;
 369
 370         root = acpi_pci_find_root(handle);
 371         if (!root)
 372                 return AE_NOT_EXIST;
 373
 374         mutex_lock(&osc_lock);
 375
 376         *mask = ctrl | root->osc_control_set;
 377         /* No need to evaluate _OSC if the control was already granted. */
 378         if ((root->osc_control_set & ctrl) == ctrl)
 379                 goto out;
 380
 381         /* Need to check the available controls bits before requesting them. */
 382         while (*mask) {
 383                 status = acpi_pci_query_osc(root, root->osc_support_set, mask);
 384                 if (ACPI_FAILURE(status))
 385                         goto out;
 386                 if (ctrl == *mask)
 387                         break;
 388                 decode_osc_control(root, "platform does not support",
 389                                    ctrl & ~(*mask));
 390                 ctrl = *mask;
 391         }
 392
 393         if ((ctrl & req) != req) {
 394                 decode_osc_control(root, "not requesting control; platform does not support",
 395                                    req & ~(ctrl));
 396                 status = AE_SUPPORT;
 397                 goto out;
 398         }
 399
 400         capbuf[OSC_QUERY_DWORD] = 0;
 401         capbuf[OSC_SUPPORT_DWORD] = root->osc_support_set;
 402         capbuf[OSC_CONTROL_DWORD] = ctrl;
 403         status = acpi_pci_run_osc(handle, capbuf, mask);
 404         if (ACPI_SUCCESS(status))
 405                 root->osc_control_set = *mask;
 406 out:
 407         mutex_unlock(&osc_lock);
 408         return status;
 409 }
 410 EXPORT_SYMBOL(acpi_pci_osc_control_set);
 411
 412 static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm,
 413                                  bool is_pcie)
 414 {
 415         u32 support, control, requested;
 416         acpi_status status;
 417         struct acpi_device *device = root->device;
 418         acpi_handle handle = device->handle;
 419
 420         /*
 421          * Apple always return failure on _OSC calls when _OSI("Darwin") has
 422          * been called successfully. We know the feature set supported by the
 423          * platform, so avoid calling _OSC at all
 424          */
 425         if (x86_apple_machine) {
 426                 root->osc_control_set = ~OSC_PCI_EXPRESS_PME_CONTROL;
 427                 decode_osc_control(root, "OS assumes control of",
 428                                    root->osc_control_set);
 429                 return;
 430         }
 431
 432         /*
 433          * All supported architectures that use ACPI have support for
 434          * PCI domains, so we indicate this in _OSC support capabilities.
 435          */
 436         support = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
 437         support |= OSC_PCI_HPX_TYPE_3_SUPPORT;
 438         if (pci_ext_cfg_avail())
 439                 support |= OSC_PCI_EXT_CONFIG_SUPPORT;
 440         if (pcie_aspm_support_enabled())
 441                 support |= OSC_PCI_ASPM_SUPPORT | OSC_PCI_CLOCK_PM_SUPPORT;
 442         if (pci_msi_enabled())
 443                 support |= OSC_PCI_MSI_SUPPORT;
 444
 445         decode_osc_support(root, "OS supports", support);
 446         status = acpi_pci_osc_support(root, support);
 447         if (ACPI_FAILURE(status)) {
 448                 *no_aspm = 1;
 449
 450                 /* _OSC is optional for PCI host bridges */
 451                 if ((status == AE_NOT_FOUND) && !is_pcie)
 452                         return;
 453
 454                 dev_info(&device->dev, "_OSC failed (%s)%s\n",
 455                          acpi_format_exception(status),
 456                          pcie_aspm_support_enabled() ? "; disabling ASPM" : "");
 457                 return;
 458         }
 459
 460         if (pcie_ports_disabled) {
 461                 dev_info(&device->dev, "PCIe port services disabled; not requesting _OSC control\n");
 462                 return;
 463         }
 464
 465         if ((support & ACPI_PCIE_REQ_SUPPORT) != ACPI_PCIE_REQ_SUPPORT) {
 466                 decode_osc_support(root, "not requesting OS control; OS requires",
 467                                    ACPI_PCIE_REQ_SUPPORT);
 468                 return;
 469         }
 470
 471         control = OSC_PCI_EXPRESS_CAPABILITY_CONTROL
 472                 | OSC_PCI_EXPRESS_PME_CONTROL;
 473
 474         if (IS_ENABLED(CONFIG_PCIEASPM))
 475                 control |= OSC_PCI_EXPRESS_LTR_CONTROL;
 476
 477         if (IS_ENABLED(CONFIG_HOTPLUG_PCI_PCIE))
 478                 control |= OSC_PCI_EXPRESS_NATIVE_HP_CONTROL;
 479
 480         if (IS_ENABLED(CONFIG_HOTPLUG_PCI_SHPC))
 481                 control |= OSC_PCI_SHPC_NATIVE_HP_CONTROL;
 482
 483         if (pci_aer_available()) {
 484                 if (aer_acpi_firmware_first())
 485                         dev_info(&device->dev,
 486                                  "PCIe AER handled by firmware\n");
 487                 else
 488                         control |= OSC_PCI_EXPRESS_AER_CONTROL;
 489         }
 490
 491         requested = control;
 492         status = acpi_pci_osc_control_set(handle, &control,
 493                                           OSC_PCI_EXPRESS_CAPABILITY_CONTROL);
 494         if (ACPI_SUCCESS(status)) {
 495                 decode_osc_control(root, "OS now controls", control);
 496                 if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) {
 497                         /*
 498                          * We have ASPM control, but the FADT indicates that
 499                          * it's unsupported. Leave existing configuration
 500                          * intact and prevent the OS from touching it.
 501                          */
 502                         dev_info(&device->dev, "FADT indicates ASPM is unsupported, using BIOS configuration\n");
 503                         *no_aspm = 1;
 504                 }
 505         } else {
 506                 decode_osc_control(root, "OS requested", requested);
 507                 decode_osc_control(root, "platform willing to grant", control);
 508                 dev_info(&device->dev, "_OSC failed (%s); disabling ASPM\n",
 509                         acpi_format_exception(status));
 510
 511                 /*
 512                  * We want to disable ASPM here, but aspm_disabled
 513                  * needs to remain in its state from boot so that we
 514                  * properly handle PCIe 1.1 devices.  So we set this
 515                  * flag here, to defer the action until after the ACPI
 516                  * root scan.
 517                  */
 518                 *no_aspm = 1;
 519         }
 520 }
 521
 522 static int acpi_pci_root_add(struct acpi_device *device,
 523                              const struct acpi_device_id *not_used)
 524 {
 525         unsigned long long segment, bus;
 526         acpi_status status;
 527         int result;
 528         struct acpi_pci_root *root;
 529         acpi_handle handle = device->handle;
 530         int no_aspm = 0;
 531         bool hotadd = system_state == SYSTEM_RUNNING;
 532         bool is_pcie;
 533
 534         root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
 535         if (!root)
 536                 return -ENOMEM;
 537
 538         segment = 0;
 539         status = acpi_evaluate_integer(handle, METHOD_NAME__SEG, NULL,
 540                                        &segment);
 541         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 542                 dev_err(&device->dev,  "can't evaluate _SEG\n");
 543                 result = -ENODEV;
 544                 goto end;
 545         }
 546
 547         /* Check _CRS first, then _BBN.  If no _BBN, default to zero. */
 548         root->secondary.flags = IORESOURCE_BUS;
 549         status = try_get_root_bridge_busnr(handle, &root->secondary);
 550         if (ACPI_FAILURE(status)) {
 551                 /*
 552                  * We need both the start and end of the downstream bus range
 553                  * to interpret _CBA (MMCONFIG base address), so it really is
 554                  * supposed to be in _CRS.  If we don't find it there, all we
 555                  * can do is assume [_BBN-0xFF] or [0-0xFF].
 556                  */
 557                 root->secondary.end = 0xFF;
 558                 dev_warn(&device->dev,
 559                          FW_BUG "no secondary bus range in _CRS\n");
 560                 status = acpi_evaluate_integer(handle, METHOD_NAME__BBN,
 561                                                NULL, &bus);
 562                 if (ACPI_SUCCESS(status))
 563                         root->secondary.start = bus;
 564                 else if (status == AE_NOT_FOUND)
 565                         root->secondary.start = 0;
 566                 else {
 567                         dev_err(&device->dev, "can't evaluate _BBN\n");
 568                         result = -ENODEV;
 569                         goto end;
 570                 }
 571         }
 572
 573         root->device = device;
 574         root->segment = segment & 0xFFFF;
 575         strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
 576         strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
 577         device->driver_data = root;
 578
 579         if (hotadd && dmar_device_add(handle)) {
 580                 result = -ENXIO;
 581                 goto end;
 582         }
 583
 584         pr_info(PREFIX "%s [%s] (domain %04x %pR)\n",
 585                acpi_device_name(device), acpi_device_bid(device),
 586                root->segment, &root->secondary);
 587
 588         root->mcfg_addr = acpi_pci_root_get_mcfg_addr(handle);
 589
 590         is_pcie = strcmp(acpi_device_hid(device), "PNP0A08") == 0;
 591         negotiate_os_control(root, &no_aspm, is_pcie);
 592
 593         /*
 594          * TBD: Need PCI interface for enumeration/configuration of roots.
 595          */
 596
 597         /*
 598          * Scan the Root Bridge
 599          * --------------------
 600          * Must do this prior to any attempt to bind the root device, as the
 601          * PCI namespace does not get created until this call is made (and
 602          * thus the root bridge's pci_dev does not exist).
 603          */
 604         root->bus = pci_acpi_scan_root(root);
 605         if (!root->bus) {
 606                 dev_err(&device->dev,
 607                         "Bus %04x:%02x not present in PCI namespace\n",
 608                         root->segment, (unsigned int)root->secondary.start);
 609                 device->driver_data = NULL;
 610                 result = -ENODEV;
 611                 goto remove_dmar;
 612         }
 613
 614         if (no_aspm)
 615                 pcie_no_aspm();
 616
 617         pci_acpi_add_bus_pm_notifier(device);
 618         device_set_wakeup_capable(root->bus->bridge, device->wakeup.flags.valid);
 619
 620         if (hotadd) {
 621                 pcibios_resource_survey_bus(root->bus);
 622                 pci_assign_unassigned_root_bus_resources(root->bus);
 623                 /*
 624                  * This is only called for the hotadd case. For the boot-time
 625                  * case, we need to wait until after PCI initialization in
 626                  * order to deal with IOAPICs mapped in on a PCI BAR.
 627                  *
 628                  * This is currently x86-specific, because acpi_ioapic_add()
 629                  * is an empty function without CONFIG_ACPI_HOTPLUG_IOAPIC.
 630                  * And CONFIG_ACPI_HOTPLUG_IOAPIC depends on CONFIG_X86_IO_APIC
 631                  * (see drivers/acpi/Kconfig).
 632                  */
 633                 acpi_ioapic_add(root->device->handle);
 634         }
 635
 636         pci_lock_rescan_remove();
 637         pci_bus_add_devices(root->bus);
 638         pci_unlock_rescan_remove();
 639         return 1;
 640
 641 remove_dmar:
 642         if (hotadd)
 643                 dmar_device_remove(handle);
 644 end:
 645         kfree(root);
 646         return result;
 647 }
 648
 649 static void acpi_pci_root_remove(struct acpi_device *device)
 650 {
 651         struct acpi_pci_root *root = acpi_driver_data(device);
 652
 653         pci_lock_rescan_remove();
 654
 655         pci_stop_root_bus(root->bus);
 656
 657         pci_ioapic_remove(root);
 658         device_set_wakeup_capable(root->bus->bridge, false);
 659         pci_acpi_remove_bus_pm_notifier(device);
 660
 661         pci_remove_root_bus(root->bus);
 662         WARN_ON(acpi_ioapic_remove(root));
 663
 664         dmar_device_remove(device->handle);
 665
 666         pci_unlock_rescan_remove();
 667
 668         kfree(root);
 669 }
 670
 671 /*
 672  * Following code to support acpi_pci_root_create() is copied from
 673  * arch/x86/pci/acpi.c and modified so it could be reused by x86, IA64
 674  * and ARM64.
 675  */
 676 static void acpi_pci_root_validate_resources(struct device *dev,
 677                                              struct list_head *resources,
 678                                              unsigned long type)
 679 {
 680         LIST_HEAD(list);
 681         struct resource *res1, *res2, *root = NULL;
 682         struct resource_entry *tmp, *entry, *entry2;
 683
 684         BUG_ON((type & (IORESOURCE_MEM | IORESOURCE_IO)) == 0);
 685         root = (type & IORESOURCE_MEM) ? &iomem_resource : &ioport_resource;
 686
 687         list_splice_init(resources, &list);
 688         resource_list_for_each_entry_safe(entry, tmp, &list) {
 689                 bool free = false;
 690                 resource_size_t end;
 691
 692                 res1 = entry->res;
 693                 if (!(res1->flags & type))
 694                         goto next;
 695
 696                 /* Exclude non-addressable range or non-addressable portion */
 697                 end = min(res1->end, root->end);
 698                 if (end <= res1->start) {
 699                         dev_info(dev, "host bridge window %pR (ignored, not CPU addressable)\n",
 700                                  res1);
 701                         free = true;
 702                         goto next;
 703                 } else if (res1->end != end) {
 704                         dev_info(dev, "host bridge window %pR ([%#llx-%#llx] ignored, not CPU addressable)\n",
 705                                  res1, (unsigned long long)end + 1,
 706                                  (unsigned long long)res1->end);
 707                         res1->end = end;
 708                 }
 709
 710                 resource_list_for_each_entry(entry2, resources) {
 711                         res2 = entry2->res;
 712                         if (!(res2->flags & type))
 713                                 continue;
 714
 715                         /*
 716                          * I don't like throwing away windows because then
 717                          * our resources no longer match the ACPI _CRS, but
 718                          * the kernel resource tree doesn't allow overlaps.
 719                          */
 720                         if (resource_overlaps(res1, res2)) {
 721                                 res2->start = min(res1->start, res2->start);
 722                                 res2->end = max(res1->end, res2->end);
 723                                 dev_info(dev, "host bridge window expanded to %pR; %pR ignored\n",
 724                                          res2, res1);
 725                                 free = true;
 726                                 goto next;
 727                         }
 728                 }
 729
 730 next:
 731                 resource_list_del(entry);
 732                 if (free)
 733                         resource_list_free_entry(entry);
 734                 else
 735                         resource_list_add_tail(entry, resources);
 736         }
 737 }
 738
 739 static void acpi_pci_root_remap_iospace(struct fwnode_handle *fwnode,
 740                         struct resource_entry *entry)
 741 {
 742 #ifdef PCI_IOBASE
 743         struct resource *res = entry->res;
 744         resource_size_t cpu_addr = res->start;
 745         resource_size_t pci_addr = cpu_addr - entry->offset;
 746         resource_size_t length = resource_size(res);
 747         unsigned long port;
 748
 749         if (pci_register_io_range(fwnode, cpu_addr, length))
 750                 goto err;
 751
 752         port = pci_address_to_pio(cpu_addr);
 753         if (port == (unsigned long)-1)
 754                 goto err;
 755
 756         res->start = port;
 757         res->end = port + length - 1;
 758         entry->offset = port - pci_addr;
 759
 760         if (pci_remap_iospace(res, cpu_addr) < 0)
 761                 goto err;
 762
 763         pr_info("Remapped I/O %pa to %pR\n", &cpu_addr, res);
 764         return;
 765 err:
 766         res->flags |= IORESOURCE_DISABLED;
 767 #endif
 768 }
 769
 770 int acpi_pci_probe_root_resources(struct acpi_pci_root_info *info)
 771 {
 772         int ret;
 773         struct list_head *list = &info->resources;
 774         struct acpi_device *device = info->bridge;
 775         struct resource_entry *entry, *tmp;
 776         unsigned long flags;
 777
 778         flags = IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_MEM_8AND16BIT;
 779         ret = acpi_dev_get_resources(device, list,
 780                                      acpi_dev_filter_resource_type_cb,
 781                                      (void *)flags);
 782         if (ret < 0)
 783                 dev_warn(&device->dev,
 784                          "failed to parse _CRS method, error code %d\n", ret);
 785         else if (ret == 0)
 786                 dev_dbg(&device->dev,
 787                         "no IO and memory resources present in _CRS\n");
 788         else {
 789                 resource_list_for_each_entry_safe(entry, tmp, list) {
 790                         if (entry->res->flags & IORESOURCE_IO)
 791                                 acpi_pci_root_remap_iospace(&device->fwnode,
 792                                                 entry);
 793
 794                         if (entry->res->flags & IORESOURCE_DISABLED)
 795                                 resource_list_destroy_entry(entry);
 796                         else
 797                                 entry->res->name = info->name;
 798                 }
 799                 acpi_pci_root_validate_resources(&device->dev, list,
 800                                                  IORESOURCE_MEM);
 801                 acpi_pci_root_validate_resources(&device->dev, list,
 802                                                  IORESOURCE_IO);
 803         }
 804
 805         return ret;
 806 }
 807
 808 static void pci_acpi_root_add_resources(struct acpi_pci_root_info *info)
 809 {
 810         struct resource_entry *entry, *tmp;
 811         struct resource *res, *conflict, *root = NULL;
 812
 813         resource_list_for_each_entry_safe(entry, tmp, &info->resources) {
 814                 res = entry->res;
 815                 if (res->flags & IORESOURCE_MEM)
 816                         root = &iomem_resource;
 817                 else if (res->flags & IORESOURCE_IO)
 818                         root = &ioport_resource;
 819                 else
 820                         continue;
 821
 822                 /*
 823                  * Some legacy x86 host bridge drivers use iomem_resource and
 824                  * ioport_resource as default resource pool, skip it.
 825                  */
 826                 if (res == root)
 827                         continue;
 828
 829                 conflict = insert_resource_conflict(root, res);
 830                 if (conflict) {
 831                         dev_info(&info->bridge->dev,
 832                                  "ignoring host bridge window %pR (conflicts with %s %pR)\n",
 833                                  res, conflict->name, conflict);
 834                         resource_list_destroy_entry(entry);
 835                 }
 836         }
 837 }
 838
 839 static void __acpi_pci_root_release_info(struct acpi_pci_root_info *info)
 840 {
 841         struct resource *res;
 842         struct resource_entry *entry, *tmp;
 843
 844         if (!info)
 845                 return;
 846
 847         resource_list_for_each_entry_safe(entry, tmp, &info->resources) {
 848                 res = entry->res;
 849                 if (res->parent &&
 850                     (res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
 851                         release_resource(res);
 852                 resource_list_destroy_entry(entry);
 853         }
 854
 855         info->ops->release_info(info);
 856 }
 857
 858 static void acpi_pci_root_release_info(struct pci_host_bridge *bridge)
 859 {
 860         struct resource *res;
 861         struct resource_entry *entry;
 862
 863         resource_list_for_each_entry(entry, &bridge->windows) {
 864                 res = entry->res;
 865                 if (res->flags & IORESOURCE_IO)
 866                         pci_unmap_iospace(res);
 867                 if (res->parent &&
 868                     (res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
 869                         release_resource(res);
 870         }
 871         __acpi_pci_root_release_info(bridge->release_data);
 872 }
 873
 874 struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root,
 875                                      struct acpi_pci_root_ops *ops,
 876                                      struct acpi_pci_root_info *info,
 877                                      void *sysdata)
 878 {
 879         int ret, busnum = root->secondary.start;
 880         struct acpi_device *device = root->device;
 881         int node = acpi_get_node(device->handle);
 882         struct pci_bus *bus;
 883         struct pci_host_bridge *host_bridge;
 884         union acpi_object *obj;
 885
 886         info->root = root;
 887         info->bridge = device;
 888         info->ops = ops;
 889         INIT_LIST_HEAD(&info->resources);
 890         snprintf(info->name, sizeof(info->name), "PCI Bus %04x:%02x",
 891                  root->segment, busnum);
 892
 893         if (ops->init_info && ops->init_info(info))
 894                 goto out_release_info;
 895         if (ops->prepare_resources)
 896                 ret = ops->prepare_resources(info);
 897         else
 898                 ret = acpi_pci_probe_root_resources(info);
 899         if (ret < 0)
 900                 goto out_release_info;
 901
 902         pci_acpi_root_add_resources(info);
 903         pci_add_resource(&info->resources, &root->secondary);
 904         bus = pci_create_root_bus(NULL, busnum, ops->pci_ops,
 905                                   sysdata, &info->resources);
 906         if (!bus)
 907                 goto out_release_info;
 908
 909         host_bridge = to_pci_host_bridge(bus->bridge);
 910         if (!(root->osc_control_set & OSC_PCI_EXPRESS_NATIVE_HP_CONTROL))
 911                 host_bridge->native_pcie_hotplug = 0;
 912         if (!(root->osc_control_set & OSC_PCI_SHPC_NATIVE_HP_CONTROL))
 913                 host_bridge->native_shpc_hotplug = 0;
 914         if (!(root->osc_control_set & OSC_PCI_EXPRESS_AER_CONTROL))
 915                 host_bridge->native_aer = 0;
 916         if (!(root->osc_control_set & OSC_PCI_EXPRESS_PME_CONTROL))
 917                 host_bridge->native_pme = 0;
 918         if (!(root->osc_control_set & OSC_PCI_EXPRESS_LTR_CONTROL))
 919                 host_bridge->native_ltr = 0;
 920
 921         /*
 922          * Evaluate the "PCI Boot Configuration" _DSM Function.  If it
 923          * exists and returns 0, we must preserve any PCI resource
 924          * assignments made by firmware for this host bridge.
 925          */
 926         obj = acpi_evaluate_dsm(ACPI_HANDLE(bus->bridge), &pci_acpi_dsm_guid, 1,
 927                                 IGNORE_PCI_BOOT_CONFIG_DSM, NULL);
 928         if (obj && obj->type == ACPI_TYPE_INTEGER && obj->integer.value == 0)
 929                 host_bridge->preserve_config = 1;
 930         ACPI_FREE(obj);
 931
 932         pci_scan_child_bus(bus);
 933         pci_set_host_bridge_release(host_bridge, acpi_pci_root_release_info,
 934                                     info);
 935         if (node != NUMA_NO_NODE)
 936                 dev_printk(KERN_DEBUG, &bus->dev, "on NUMA node %d\n", node);
 937         return bus;
 938
 939 out_release_info:
 940         __acpi_pci_root_release_info(info);
 941         return NULL;
 942 }
 943
 944 void __init acpi_pci_root_init(void)
 945 {
 946         acpi_hest_init();
 947         if (acpi_pci_disabled)
 948                 return;
 949
 950         pci_acpi_crs_quirks();
 951         acpi_scan_add_handler_with_hotplug(&pci_root_handler, "pci_root");
 952 }