drivers/pci/pci-acpi.c

   1 /*
   2  * File:        pci-acpi.c
   3  * Purpose:     Provide PCI support in ACPI
   4  *
   5  * Copyright (C) 2005 David Shaohua Li <shaohua.li@intel.com>
   6  * Copyright (C) 2004 Tom Long Nguyen <tom.l.nguyen@intel.com>
   7  * Copyright (C) 2004 Intel Corp.
   8  */
   9
  10 #include <linux/delay.h>
  11 #include <linux/init.h>
  12 #include <linux/irqdomain.h>
  13 #include <linux/pci.h>
  14 #include <linux/msi.h>
  15 #include <linux/pci_hotplug.h>
  16 #include <linux/module.h>
  17 #include <linux/pci-aspm.h>
  18 #include <linux/pci-acpi.h>
  19 #include <linux/pm_runtime.h>
  20 #include <linux/pm_qos.h>
  21 #include "pci.h"
  22
  23 /*
  24  * The GUID is defined in the PCI Firmware Specification available here:
  25  * https://www.pcisig.com/members/downloads/pcifw_r3_1_13Dec10.pdf
  26  */
  27 const guid_t pci_acpi_dsm_guid =
  28         GUID_INIT(0xe5c937d0, 0x3553, 0x4d7a,
  29                   0x91, 0x17, 0xea, 0x4d, 0x19, 0xc3, 0x43, 0x4d);
  30
  31 #if defined(CONFIG_PCI_QUIRKS) && defined(CONFIG_ARM64)
  32 static int acpi_get_rc_addr(struct acpi_device *adev, struct resource *res)
  33 {
  34         struct device *dev = &adev->dev;
  35         struct resource_entry *entry;
  36         struct list_head list;
  37         unsigned long flags;
  38         int ret;
  39
  40         INIT_LIST_HEAD(&list);
  41         flags = IORESOURCE_MEM;
  42         ret = acpi_dev_get_resources(adev, &list,
  43                                      acpi_dev_filter_resource_type_cb,
  44                                      (void *) flags);
  45         if (ret < 0) {
  46                 dev_err(dev, "failed to parse _CRS method, error code %d\n",
  47                         ret);
  48                 return ret;
  49         }
  50
  51         if (ret == 0) {
  52                 dev_err(dev, "no IO and memory resources present in _CRS\n");
  53                 return -EINVAL;
  54         }
  55
  56         entry = list_first_entry(&list, struct resource_entry, node);
  57         *res = *entry->res;
  58         acpi_dev_free_resource_list(&list);
  59         return 0;
  60 }
  61
  62 static acpi_status acpi_match_rc(acpi_handle handle, u32 lvl, void *context,
  63                                  void **retval)
  64 {
  65         u16 *segment = context;
  66         unsigned long long uid;
  67         acpi_status status;
  68
  69         status = acpi_evaluate_integer(handle, "_UID", NULL, &uid);
  70         if (ACPI_FAILURE(status) || uid != *segment)
  71                 return AE_CTRL_DEPTH;
  72
  73         *(acpi_handle *)retval = handle;
  74         return AE_CTRL_TERMINATE;
  75 }
  76
  77 int acpi_get_rc_resources(struct device *dev, const char *hid, u16 segment,
  78                           struct resource *res)
  79 {
  80         struct acpi_device *adev;
  81         acpi_status status;
  82         acpi_handle handle;
  83         int ret;
  84
  85         status = acpi_get_devices(hid, acpi_match_rc, &segment, &handle);
  86         if (ACPI_FAILURE(status)) {
  87                 dev_err(dev, "can't find _HID %s device to locate resources\n",
  88                         hid);
  89                 return -ENODEV;
  90         }
  91
  92         ret = acpi_bus_get_device(handle, &adev);
  93         if (ret)
  94                 return ret;
  95
  96         ret = acpi_get_rc_addr(adev, res);
  97         if (ret) {
  98                 dev_err(dev, "can't get resource from %s\n",
  99                         dev_name(&adev->dev));
 100                 return ret;
 101         }
 102
 103         return 0;
 104 }
 105 #endif
 106
 107 phys_addr_t acpi_pci_root_get_mcfg_addr(acpi_handle handle)
 108 {
 109         acpi_status status = AE_NOT_EXIST;
 110         unsigned long long mcfg_addr;
 111
 112         if (handle)
 113                 status = acpi_evaluate_integer(handle, METHOD_NAME__CBA,
 114                                                NULL, &mcfg_addr);
 115         if (ACPI_FAILURE(status))
 116                 return 0;
 117
 118         return (phys_addr_t)mcfg_addr;
 119 }
 120
 121 static acpi_status decode_type0_hpx_record(union acpi_object *record,
 122                                            struct hotplug_params *hpx)
 123 {
 124         int i;
 125         union acpi_object *fields = record->package.elements;
 126         u32 revision = fields[1].integer.value;
 127
 128         switch (revision) {
 129         case 1:
 130                 if (record->package.count != 6)
 131                         return AE_ERROR;
 132                 for (i = 2; i < 6; i++)
 133                         if (fields[i].type != ACPI_TYPE_INTEGER)
 134                                 return AE_ERROR;
 135                 hpx->t0 = &hpx->type0_data;
 136                 hpx->t0->revision        = revision;
 137                 hpx->t0->cache_line_size = fields[2].integer.value;
 138                 hpx->t0->latency_timer   = fields[3].integer.value;
 139                 hpx->t0->enable_serr     = fields[4].integer.value;
 140                 hpx->t0->enable_perr     = fields[5].integer.value;
 141                 break;
 142         default:
 143                 printk(KERN_WARNING
 144                        "%s: Type 0 Revision %d record not supported\n",
 145                        __func__, revision);
 146                 return AE_ERROR;
 147         }
 148         return AE_OK;
 149 }
 150
 151 static acpi_status decode_type1_hpx_record(union acpi_object *record,
 152                                            struct hotplug_params *hpx)
 153 {
 154         int i;
 155         union acpi_object *fields = record->package.elements;
 156         u32 revision = fields[1].integer.value;
 157
 158         switch (revision) {
 159         case 1:
 160                 if (record->package.count != 5)
 161                         return AE_ERROR;
 162                 for (i = 2; i < 5; i++)
 163                         if (fields[i].type != ACPI_TYPE_INTEGER)
 164                                 return AE_ERROR;
 165                 hpx->t1 = &hpx->type1_data;
 166                 hpx->t1->revision      = revision;
 167                 hpx->t1->max_mem_read  = fields[2].integer.value;
 168                 hpx->t1->avg_max_split = fields[3].integer.value;
 169                 hpx->t1->tot_max_split = fields[4].integer.value;
 170                 break;
 171         default:
 172                 printk(KERN_WARNING
 173                        "%s: Type 1 Revision %d record not supported\n",
 174                        __func__, revision);
 175                 return AE_ERROR;
 176         }
 177         return AE_OK;
 178 }
 179
 180 static acpi_status decode_type2_hpx_record(union acpi_object *record,
 181                                            struct hotplug_params *hpx)
 182 {
 183         int i;
 184         union acpi_object *fields = record->package.elements;
 185         u32 revision = fields[1].integer.value;
 186
 187         switch (revision) {
 188         case 1:
 189                 if (record->package.count != 18)
 190                         return AE_ERROR;
 191                 for (i = 2; i < 18; i++)
 192                         if (fields[i].type != ACPI_TYPE_INTEGER)
 193                                 return AE_ERROR;
 194                 hpx->t2 = &hpx->type2_data;
 195                 hpx->t2->revision      = revision;
 196                 hpx->t2->unc_err_mask_and      = fields[2].integer.value;
 197                 hpx->t2->unc_err_mask_or       = fields[3].integer.value;
 198                 hpx->t2->unc_err_sever_and     = fields[4].integer.value;
 199                 hpx->t2->unc_err_sever_or      = fields[5].integer.value;
 200                 hpx->t2->cor_err_mask_and      = fields[6].integer.value;
 201                 hpx->t2->cor_err_mask_or       = fields[7].integer.value;
 202                 hpx->t2->adv_err_cap_and       = fields[8].integer.value;
 203                 hpx->t2->adv_err_cap_or        = fields[9].integer.value;
 204                 hpx->t2->pci_exp_devctl_and    = fields[10].integer.value;
 205                 hpx->t2->pci_exp_devctl_or     = fields[11].integer.value;
 206                 hpx->t2->pci_exp_lnkctl_and    = fields[12].integer.value;
 207                 hpx->t2->pci_exp_lnkctl_or     = fields[13].integer.value;
 208                 hpx->t2->sec_unc_err_sever_and = fields[14].integer.value;
 209                 hpx->t2->sec_unc_err_sever_or  = fields[15].integer.value;
 210                 hpx->t2->sec_unc_err_mask_and  = fields[16].integer.value;
 211                 hpx->t2->sec_unc_err_mask_or   = fields[17].integer.value;
 212                 break;
 213         default:
 214                 printk(KERN_WARNING
 215                        "%s: Type 2 Revision %d record not supported\n",
 216                        __func__, revision);
 217                 return AE_ERROR;
 218         }
 219         return AE_OK;
 220 }
 221
 222 static acpi_status acpi_run_hpx(acpi_handle handle, struct hotplug_params *hpx)
 223 {
 224         acpi_status status;
 225         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
 226         union acpi_object *package, *record, *fields;
 227         u32 type;
 228         int i;
 229
 230         /* Clear the return buffer with zeros */
 231         memset(hpx, 0, sizeof(struct hotplug_params));
 232
 233         status = acpi_evaluate_object(handle, "_HPX", NULL, &buffer);
 234         if (ACPI_FAILURE(status))
 235                 return status;
 236
 237         package = (union acpi_object *)buffer.pointer;
 238         if (package->type != ACPI_TYPE_PACKAGE) {
 239                 status = AE_ERROR;
 240                 goto exit;
 241         }
 242
 243         for (i = 0; i < package->package.count; i++) {
 244                 record = &package->package.elements[i];
 245                 if (record->type != ACPI_TYPE_PACKAGE) {
 246                         status = AE_ERROR;
 247                         goto exit;
 248                 }
 249
 250                 fields = record->package.elements;
 251                 if (fields[0].type != ACPI_TYPE_INTEGER ||
 252                     fields[1].type != ACPI_TYPE_INTEGER) {
 253                         status = AE_ERROR;
 254                         goto exit;
 255                 }
 256
 257                 type = fields[0].integer.value;
 258                 switch (type) {
 259                 case 0:
 260                         status = decode_type0_hpx_record(record, hpx);
 261                         if (ACPI_FAILURE(status))
 262                                 goto exit;
 263                         break;
 264                 case 1:
 265                         status = decode_type1_hpx_record(record, hpx);
 266                         if (ACPI_FAILURE(status))
 267                                 goto exit;
 268                         break;
 269                 case 2:
 270                         status = decode_type2_hpx_record(record, hpx);
 271                         if (ACPI_FAILURE(status))
 272                                 goto exit;
 273                         break;
 274                 default:
 275                         printk(KERN_ERR "%s: Type %d record not supported\n",
 276                                __func__, type);
 277                         status = AE_ERROR;
 278                         goto exit;
 279                 }
 280         }
 281  exit:
 282         kfree(buffer.pointer);
 283         return status;
 284 }
 285
 286 static acpi_status acpi_run_hpp(acpi_handle handle, struct hotplug_params *hpp)
 287 {
 288         acpi_status status;
 289         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 290         union acpi_object *package, *fields;
 291         int i;
 292
 293         memset(hpp, 0, sizeof(struct hotplug_params));
 294
 295         status = acpi_evaluate_object(handle, "_HPP", NULL, &buffer);
 296         if (ACPI_FAILURE(status))
 297                 return status;
 298
 299         package = (union acpi_object *) buffer.pointer;
 300         if (package->type != ACPI_TYPE_PACKAGE ||
 301             package->package.count != 4) {
 302                 status = AE_ERROR;
 303                 goto exit;
 304         }
 305
 306         fields = package->package.elements;
 307         for (i = 0; i < 4; i++) {
 308                 if (fields[i].type != ACPI_TYPE_INTEGER) {
 309                         status = AE_ERROR;
 310                         goto exit;
 311                 }
 312         }
 313
 314         hpp->t0 = &hpp->type0_data;
 315         hpp->t0->revision        = 1;
 316         hpp->t0->cache_line_size = fields[0].integer.value;
 317         hpp->t0->latency_timer   = fields[1].integer.value;
 318         hpp->t0->enable_serr     = fields[2].integer.value;
 319         hpp->t0->enable_perr     = fields[3].integer.value;
 320
 321 exit:
 322         kfree(buffer.pointer);
 323         return status;
 324 }
 325
 326 /* pci_get_hp_params
 327  *
 328  * @dev - the pci_dev for which we want parameters
 329  * @hpp - allocated by the caller
 330  */
 331 int pci_get_hp_params(struct pci_dev *dev, struct hotplug_params *hpp)
 332 {
 333         acpi_status status;
 334         acpi_handle handle, phandle;
 335         struct pci_bus *pbus;
 336
 337         if (acpi_pci_disabled)
 338                 return -ENODEV;
 339
 340         handle = NULL;
 341         for (pbus = dev->bus; pbus; pbus = pbus->parent) {
 342                 handle = acpi_pci_get_bridge_handle(pbus);
 343                 if (handle)
 344                         break;
 345         }
 346
 347         /*
 348          * _HPP settings apply to all child buses, until another _HPP is
 349          * encountered. If we don't find an _HPP for the input pci dev,
 350          * look for it in the parent device scope since that would apply to
 351          * this pci dev.
 352          */
 353         while (handle) {
 354                 status = acpi_run_hpx(handle, hpp);
 355                 if (ACPI_SUCCESS(status))
 356                         return 0;
 357                 status = acpi_run_hpp(handle, hpp);
 358                 if (ACPI_SUCCESS(status))
 359                         return 0;
 360                 if (acpi_is_root_bridge(handle))
 361                         break;
 362                 status = acpi_get_parent(handle, &phandle);
 363                 if (ACPI_FAILURE(status))
 364                         break;
 365                 handle = phandle;
 366         }
 367         return -ENODEV;
 368 }
 369 EXPORT_SYMBOL_GPL(pci_get_hp_params);
 370
 371 /**
 372  * pciehp_is_native - Check whether a hotplug port is handled by the OS
 373  * @pdev: Hotplug port to check
 374  *
 375  * Walk up from @pdev to the host bridge, obtain its cached _OSC Control Field
 376  * and return the value of the "PCI Express Native Hot Plug control" bit.
 377  * On failure to obtain the _OSC Control Field return %false.
 378  */
 379 bool pciehp_is_native(struct pci_dev *pdev)
 380 {
 381         struct acpi_pci_root *root;
 382         acpi_handle handle;
 383
 384         handle = acpi_find_root_bridge_handle(pdev);
 385         if (!handle)
 386                 return false;
 387
 388         root = acpi_pci_find_root(handle);
 389         if (!root)
 390                 return false;
 391
 392         return root->osc_control_set & OSC_PCI_EXPRESS_NATIVE_HP_CONTROL;
 393 }
 394
 395 /**
 396  * pci_acpi_wake_bus - Root bus wakeup notification fork function.
 397  * @work: Work item to handle.
 398  */
 399 static void pci_acpi_wake_bus(struct work_struct *work)
 400 {
 401         struct acpi_device *adev;
 402         struct acpi_pci_root *root;
 403
 404         adev = container_of(work, struct acpi_device, wakeup.context.work);
 405         root = acpi_driver_data(adev);
 406         pci_pme_wakeup_bus(root->bus);
 407 }
 408
 409 /**
 410  * pci_acpi_wake_dev - PCI device wakeup notification work function.
 411  * @handle: ACPI handle of a device the notification is for.
 412  * @work: Work item to handle.
 413  */
 414 static void pci_acpi_wake_dev(struct work_struct *work)
 415 {
 416         struct acpi_device_wakeup_context *context;
 417         struct pci_dev *pci_dev;
 418
 419         context = container_of(work, struct acpi_device_wakeup_context, work);
 420         pci_dev = to_pci_dev(context->dev);
 421
 422         if (pci_dev->pme_poll)
 423                 pci_dev->pme_poll = false;
 424
 425         if (pci_dev->current_state == PCI_D3cold) {
 426                 pci_wakeup_event(pci_dev);
 427                 pm_runtime_resume(&pci_dev->dev);
 428                 return;
 429         }
 430
 431         /* Clear PME Status if set. */
 432         if (pci_dev->pme_support)
 433                 pci_check_pme_status(pci_dev);
 434
 435         pci_wakeup_event(pci_dev);
 436         pm_runtime_resume(&pci_dev->dev);
 437
 438         pci_pme_wakeup_bus(pci_dev->subordinate);
 439 }
 440
 441 /**
 442  * pci_acpi_add_bus_pm_notifier - Register PM notifier for root PCI bus.
 443  * @dev: PCI root bridge ACPI device.
 444  */
 445 acpi_status pci_acpi_add_bus_pm_notifier(struct acpi_device *dev)
 446 {
 447         return acpi_add_pm_notifier(dev, NULL, pci_acpi_wake_bus);
 448 }
 449
 450 /**
 451  * pci_acpi_add_pm_notifier - Register PM notifier for given PCI device.
 452  * @dev: ACPI device to add the notifier for.
 453  * @pci_dev: PCI device to check for the PME status if an event is signaled.
 454  */
 455 acpi_status pci_acpi_add_pm_notifier(struct acpi_device *dev,
 456                                      struct pci_dev *pci_dev)
 457 {
 458         return acpi_add_pm_notifier(dev, &pci_dev->dev, pci_acpi_wake_dev);
 459 }
 460
 461 /*
 462  * _SxD returns the D-state with the highest power
 463  * (lowest D-state number) supported in the S-state "x".
 464  *
 465  * If the devices does not have a _PRW
 466  * (Power Resources for Wake) supporting system wakeup from "x"
 467  * then the OS is free to choose a lower power (higher number
 468  * D-state) than the return value from _SxD.
 469  *
 470  * But if _PRW is enabled at S-state "x", the OS
 471  * must not choose a power lower than _SxD --
 472  * unless the device has an _SxW method specifying
 473  * the lowest power (highest D-state number) the device
 474  * may enter while still able to wake the system.
 475  *
 476  * ie. depending on global OS policy:
 477  *
 478  * if (_PRW at S-state x)
 479  *      choose from highest power _SxD to lowest power _SxW
 480  * else // no _PRW at S-state x
 481  *      choose highest power _SxD or any lower power
 482  */
 483
 484 static pci_power_t acpi_pci_choose_state(struct pci_dev *pdev)
 485 {
 486         int acpi_state, d_max;
 487
 488         if (pdev->no_d3cold)
 489                 d_max = ACPI_STATE_D3_HOT;
 490         else
 491                 d_max = ACPI_STATE_D3_COLD;
 492         acpi_state = acpi_pm_device_sleep_state(&pdev->dev, NULL, d_max);
 493         if (acpi_state < 0)
 494                 return PCI_POWER_ERROR;
 495
 496         switch (acpi_state) {
 497         case ACPI_STATE_D0:
 498                 return PCI_D0;
 499         case ACPI_STATE_D1:
 500                 return PCI_D1;
 501         case ACPI_STATE_D2:
 502                 return PCI_D2;
 503         case ACPI_STATE_D3_HOT:
 504                 return PCI_D3hot;
 505         case ACPI_STATE_D3_COLD:
 506                 return PCI_D3cold;
 507         }
 508         return PCI_POWER_ERROR;
 509 }
 510
 511 static bool acpi_pci_power_manageable(struct pci_dev *dev)
 512 {
 513         struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
 514         return adev ? acpi_device_power_manageable(adev) : false;
 515 }
 516
 517 static int acpi_pci_set_power_state(struct pci_dev *dev, pci_power_t state)
 518 {
 519         struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
 520         static const u8 state_conv[] = {
 521                 [PCI_D0] = ACPI_STATE_D0,
 522                 [PCI_D1] = ACPI_STATE_D1,
 523                 [PCI_D2] = ACPI_STATE_D2,
 524                 [PCI_D3hot] = ACPI_STATE_D3_HOT,
 525                 [PCI_D3cold] = ACPI_STATE_D3_COLD,
 526         };
 527         int error = -EINVAL;
 528
 529         /* If the ACPI device has _EJ0, ignore the device */
 530         if (!adev || acpi_has_method(adev->handle, "_EJ0"))
 531                 return -ENODEV;
 532
 533         switch (state) {
 534         case PCI_D3cold:
 535                 if (dev_pm_qos_flags(&dev->dev, PM_QOS_FLAG_NO_POWER_OFF) ==
 536                                 PM_QOS_FLAGS_ALL) {
 537                         error = -EBUSY;
 538                         break;
 539                 }
 540         case PCI_D0:
 541         case PCI_D1:
 542         case PCI_D2:
 543         case PCI_D3hot:
 544                 error = acpi_device_set_power(adev, state_conv[state]);
 545         }
 546
 547         if (!error)
 548                 dev_dbg(&dev->dev, "power state changed by ACPI to %s\n",
 549                          acpi_power_state_string(state_conv[state]));
 550
 551         return error;
 552 }
 553
 554 static pci_power_t acpi_pci_get_power_state(struct pci_dev *dev)
 555 {
 556         struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
 557         static const pci_power_t state_conv[] = {
 558                 [ACPI_STATE_D0]      = PCI_D0,
 559                 [ACPI_STATE_D1]      = PCI_D1,
 560                 [ACPI_STATE_D2]      = PCI_D2,
 561                 [ACPI_STATE_D3_HOT]  = PCI_D3hot,
 562                 [ACPI_STATE_D3_COLD] = PCI_D3cold,
 563         };
 564         int state;
 565
 566         if (!adev || !acpi_device_power_manageable(adev))
 567                 return PCI_UNKNOWN;
 568
 569         if (acpi_device_get_power(adev, &state) || state == ACPI_STATE_UNKNOWN)
 570                 return PCI_UNKNOWN;
 571
 572         return state_conv[state];
 573 }
 574
 575 static bool acpi_pci_can_wakeup(struct pci_dev *dev)
 576 {
 577         struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
 578         return adev ? acpi_device_can_wakeup(adev) : false;
 579 }
 580
 581 static void acpi_pci_propagate_wakeup_enable(struct pci_bus *bus, bool enable)
 582 {
 583         while (bus->parent) {
 584                 if (!acpi_pm_device_sleep_wake(&bus->self->dev, enable))
 585                         return;
 586                 bus = bus->parent;
 587         }
 588
 589         /* We have reached the root bus. */
 590         if (bus->bridge)
 591                 acpi_pm_device_sleep_wake(bus->bridge, enable);
 592 }
 593
 594 static int acpi_pci_sleep_wake(struct pci_dev *dev, bool enable)
 595 {
 596         if (acpi_pci_can_wakeup(dev))
 597                 return acpi_pm_device_sleep_wake(&dev->dev, enable);
 598
 599         acpi_pci_propagate_wakeup_enable(dev->bus, enable);
 600         return 0;
 601 }
 602
 603 static void acpi_pci_propagate_run_wake(struct pci_bus *bus, bool enable)
 604 {
 605         while (bus->parent) {
 606                 struct pci_dev *bridge = bus->self;
 607
 608                 if (bridge->pme_interrupt)
 609                         return;
 610                 if (!acpi_pm_device_run_wake(&bridge->dev, enable))
 611                         return;
 612                 bus = bus->parent;
 613         }
 614
 615         /* We have reached the root bus. */
 616         if (bus->bridge)
 617                 acpi_pm_device_run_wake(bus->bridge, enable);
 618 }
 619
 620 static int acpi_pci_run_wake(struct pci_dev *dev, bool enable)
 621 {
 622         /*
 623          * Per PCI Express Base Specification Revision 2.0 section
 624          * 5.3.3.2 Link Wakeup, platform support is needed for D3cold
 625          * waking up to power on the main link even if there is PME
 626          * support for D3cold
 627          */
 628         if (dev->pme_interrupt && !dev->runtime_d3cold)
 629                 return 0;
 630
 631         if (!acpi_pm_device_run_wake(&dev->dev, enable))
 632                 return 0;
 633
 634         acpi_pci_propagate_run_wake(dev->bus, enable);
 635         return 0;
 636 }
 637
 638 static bool acpi_pci_need_resume(struct pci_dev *dev)
 639 {
 640         struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
 641
 642         if (!adev || !acpi_device_power_manageable(adev))
 643                 return false;
 644
 645         if (device_may_wakeup(&dev->dev) != !!adev->wakeup.prepare_count)
 646                 return true;
 647
 648         if (acpi_target_system_state() == ACPI_STATE_S0)
 649                 return false;
 650
 651         return !!adev->power.flags.dsw_present;
 652 }
 653
 654 static const struct pci_platform_pm_ops acpi_pci_platform_pm = {
 655         .is_manageable = acpi_pci_power_manageable,
 656         .set_state = acpi_pci_set_power_state,
 657         .get_state = acpi_pci_get_power_state,
 658         .choose_state = acpi_pci_choose_state,
 659         .sleep_wake = acpi_pci_sleep_wake,
 660         .run_wake = acpi_pci_run_wake,
 661         .need_resume = acpi_pci_need_resume,
 662 };
 663
 664 void acpi_pci_add_bus(struct pci_bus *bus)
 665 {
 666         union acpi_object *obj;
 667         struct pci_host_bridge *bridge;
 668
 669         if (acpi_pci_disabled || !bus->bridge)
 670                 return;
 671
 672         acpi_pci_slot_enumerate(bus);
 673         acpiphp_enumerate_slots(bus);
 674
 675         /*
 676          * For a host bridge, check its _DSM for function 8 and if
 677          * that is available, mark it in pci_host_bridge.
 678          */
 679         if (!pci_is_root_bus(bus))
 680                 return;
 681
 682         obj = acpi_evaluate_dsm(ACPI_HANDLE(bus->bridge), &pci_acpi_dsm_guid, 3,
 683                                 RESET_DELAY_DSM, NULL);
 684         if (!obj)
 685                 return;
 686
 687         if (obj->type == ACPI_TYPE_INTEGER && obj->integer.value == 1) {
 688                 bridge = pci_find_host_bridge(bus);
 689                 bridge->ignore_reset_delay = 1;
 690         }
 691         ACPI_FREE(obj);
 692 }
 693
 694 void acpi_pci_remove_bus(struct pci_bus *bus)
 695 {
 696         if (acpi_pci_disabled || !bus->bridge)
 697                 return;
 698
 699         acpiphp_remove_slots(bus);
 700         acpi_pci_slot_remove(bus);
 701 }
 702
 703 /* ACPI bus type */
 704 static struct acpi_device *acpi_pci_find_companion(struct device *dev)
 705 {
 706         struct pci_dev *pci_dev = to_pci_dev(dev);
 707         bool check_children;
 708         u64 addr;
 709
 710         check_children = pci_is_bridge(pci_dev);
 711         /* Please ref to ACPI spec for the syntax of _ADR */
 712         addr = (PCI_SLOT(pci_dev->devfn) << 16) | PCI_FUNC(pci_dev->devfn);
 713         return acpi_find_child_device(ACPI_COMPANION(dev->parent), addr,
 714                                       check_children);
 715 }
 716
 717 /**
 718  * pci_acpi_optimize_delay - optimize PCI D3 and D3cold delay from ACPI
 719  * @pdev: the PCI device whose delay is to be updated
 720  * @handle: ACPI handle of this device
 721  *
 722  * Update the d3_delay and d3cold_delay of a PCI device from the ACPI _DSM
 723  * control method of either the device itself or the PCI host bridge.
 724  *
 725  * Function 8, "Reset Delay," applies to the entire hierarchy below a PCI
 726  * host bridge.  If it returns one, the OS may assume that all devices in
 727  * the hierarchy have already completed power-on reset delays.
 728  *
 729  * Function 9, "Device Readiness Durations," applies only to the object
 730  * where it is located.  It returns delay durations required after various
 731  * events if the device requires less time than the spec requires.  Delays
 732  * from this function take precedence over the Reset Delay function.
 733  *
 734  * These _DSM functions are defined by the draft ECN of January 28, 2014,
 735  * titled "ACPI additions for FW latency optimizations."
 736  */
 737 static void pci_acpi_optimize_delay(struct pci_dev *pdev,
 738                                     acpi_handle handle)
 739 {
 740         struct pci_host_bridge *bridge = pci_find_host_bridge(pdev->bus);
 741         int value;
 742         union acpi_object *obj, *elements;
 743
 744         if (bridge->ignore_reset_delay)
 745                 pdev->d3cold_delay = 0;
 746
 747         obj = acpi_evaluate_dsm(handle, &pci_acpi_dsm_guid, 3,
 748                                 FUNCTION_DELAY_DSM, NULL);
 749         if (!obj)
 750                 return;
 751
 752         if (obj->type == ACPI_TYPE_PACKAGE && obj->package.count == 5) {
 753                 elements = obj->package.elements;
 754                 if (elements[0].type == ACPI_TYPE_INTEGER) {
 755                         value = (int)elements[0].integer.value / 1000;
 756                         if (value < PCI_PM_D3COLD_WAIT)
 757                                 pdev->d3cold_delay = value;
 758                 }
 759                 if (elements[3].type == ACPI_TYPE_INTEGER) {
 760                         value = (int)elements[3].integer.value / 1000;
 761                         if (value < PCI_PM_D3_WAIT)
 762                                 pdev->d3_delay = value;
 763                 }
 764         }
 765         ACPI_FREE(obj);
 766 }
 767
 768 static void pci_acpi_setup(struct device *dev)
 769 {
 770         struct pci_dev *pci_dev = to_pci_dev(dev);
 771         struct acpi_device *adev = ACPI_COMPANION(dev);
 772
 773         if (!adev)
 774                 return;
 775
 776         pci_acpi_optimize_delay(pci_dev, adev->handle);
 777
 778         pci_acpi_add_pm_notifier(adev, pci_dev);
 779         if (!adev->wakeup.flags.valid)
 780                 return;
 781
 782         device_set_wakeup_capable(dev, true);
 783         acpi_pci_sleep_wake(pci_dev, false);
 784         if (adev->wakeup.flags.run_wake)
 785                 device_set_run_wake(dev, true);
 786 }
 787
 788 static void pci_acpi_cleanup(struct device *dev)
 789 {
 790         struct acpi_device *adev = ACPI_COMPANION(dev);
 791
 792         if (!adev)
 793                 return;
 794
 795         pci_acpi_remove_pm_notifier(adev);
 796         if (adev->wakeup.flags.valid) {
 797                 device_set_wakeup_capable(dev, false);
 798                 device_set_run_wake(dev, false);
 799         }
 800 }
 801
 802 static bool pci_acpi_bus_match(struct device *dev)
 803 {
 804         return dev_is_pci(dev);
 805 }
 806
 807 static struct acpi_bus_type acpi_pci_bus = {
 808         .name = "PCI",
 809         .match = pci_acpi_bus_match,
 810         .find_companion = acpi_pci_find_companion,
 811         .setup = pci_acpi_setup,
 812         .cleanup = pci_acpi_cleanup,
 813 };
 814
 815
 816 static struct fwnode_handle *(*pci_msi_get_fwnode_cb)(struct device *dev);
 817
 818 /**
 819  * pci_msi_register_fwnode_provider - Register callback to retrieve fwnode
 820  * @fn:       Callback matching a device to a fwnode that identifies a PCI
 821  *            MSI domain.
 822  *
 823  * This should be called by irqchip driver, which is the parent of
 824  * the MSI domain to provide callback interface to query fwnode.
 825  */
 826 void
 827 pci_msi_register_fwnode_provider(struct fwnode_handle *(*fn)(struct device *))
 828 {
 829         pci_msi_get_fwnode_cb = fn;
 830 }
 831
 832 /**
 833  * pci_host_bridge_acpi_msi_domain - Retrieve MSI domain of a PCI host bridge
 834  * @bus:      The PCI host bridge bus.
 835  *
 836  * This function uses the callback function registered by
 837  * pci_msi_register_fwnode_provider() to retrieve the irq_domain with
 838  * type DOMAIN_BUS_PCI_MSI of the specified host bridge bus.
 839  * This returns NULL on error or when the domain is not found.
 840  */
 841 struct irq_domain *pci_host_bridge_acpi_msi_domain(struct pci_bus *bus)
 842 {
 843         struct fwnode_handle *fwnode;
 844
 845         if (!pci_msi_get_fwnode_cb)
 846                 return NULL;
 847
 848         fwnode = pci_msi_get_fwnode_cb(&bus->dev);
 849         if (!fwnode)
 850                 return NULL;
 851
 852         return irq_find_matching_fwnode(fwnode, DOMAIN_BUS_PCI_MSI);
 853 }
 854
 855 static int __init acpi_pci_init(void)
 856 {
 857         int ret;
 858
 859         if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_MSI) {
 860                 pr_info("ACPI FADT declares the system doesn't support MSI, so disable it\n");
 861                 pci_no_msi();
 862         }
 863
 864         if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) {
 865                 pr_info("ACPI FADT declares the system doesn't support PCIe ASPM, so disable it\n");
 866                 pcie_no_aspm();
 867         }
 868
 869         ret = register_acpi_bus_type(&acpi_pci_bus);
 870         if (ret)
 871                 return 0;
 872
 873         pci_set_platform_pm(&acpi_pci_platform_pm);
 874         acpi_pci_slot_init();
 875         acpiphp_init();
 876
 877         return 0;
 878 }
 879 arch_initcall(acpi_pci_init);