drivers/pci/pci-acpi.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * 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  * @bridge: Hotplug port to check
 374  *
 375  * Returns true if the given @bridge is handled by the native PCIe hotplug
 376  * driver.
 377  */
 378 bool pciehp_is_native(struct pci_dev *bridge)
 379 {
 380         const struct pci_host_bridge *host;
 381         u32 slot_cap;
 382
 383         if (!IS_ENABLED(CONFIG_HOTPLUG_PCI_PCIE))
 384                 return false;
 385
 386         pcie_capability_read_dword(bridge, PCI_EXP_SLTCAP, &slot_cap);
 387         if (!(slot_cap & PCI_EXP_SLTCAP_HPC))
 388                 return false;
 389
 390         if (pcie_ports_native)
 391                 return true;
 392
 393         host = pci_find_host_bridge(bridge->bus);
 394         return host->native_pcie_hotplug;
 395 }
 396
 397 /**
 398  * shpchp_is_native - Check whether a hotplug port is handled by the OS
 399  * @bridge: Hotplug port to check
 400  *
 401  * Returns true if the given @bridge is handled by the native SHPC hotplug
 402  * driver.
 403  */
 404 bool shpchp_is_native(struct pci_dev *bridge)
 405 {
 406         return bridge->shpc_managed;
 407 }
 408
 409 /**
 410  * pci_acpi_wake_bus - Root bus wakeup notification fork function.
 411  * @context: Device wakeup context.
 412  */
 413 static void pci_acpi_wake_bus(struct acpi_device_wakeup_context *context)
 414 {
 415         struct acpi_device *adev;
 416         struct acpi_pci_root *root;
 417
 418         adev = container_of(context, struct acpi_device, wakeup.context);
 419         root = acpi_driver_data(adev);
 420         pci_pme_wakeup_bus(root->bus);
 421 }
 422
 423 /**
 424  * pci_acpi_wake_dev - PCI device wakeup notification work function.
 425  * @context: Device wakeup context.
 426  */
 427 static void pci_acpi_wake_dev(struct acpi_device_wakeup_context *context)
 428 {
 429         struct pci_dev *pci_dev;
 430
 431         pci_dev = to_pci_dev(context->dev);
 432
 433         if (pci_dev->pme_poll)
 434                 pci_dev->pme_poll = false;
 435
 436         if (pci_dev->current_state == PCI_D3cold) {
 437                 pci_wakeup_event(pci_dev);
 438                 pm_request_resume(&pci_dev->dev);
 439                 return;
 440         }
 441
 442         /* Clear PME Status if set. */
 443         if (pci_dev->pme_support)
 444                 pci_check_pme_status(pci_dev);
 445
 446         pci_wakeup_event(pci_dev);
 447         pm_request_resume(&pci_dev->dev);
 448
 449         pci_pme_wakeup_bus(pci_dev->subordinate);
 450 }
 451
 452 /**
 453  * pci_acpi_add_bus_pm_notifier - Register PM notifier for root PCI bus.
 454  * @dev: PCI root bridge ACPI device.
 455  */
 456 acpi_status pci_acpi_add_bus_pm_notifier(struct acpi_device *dev)
 457 {
 458         return acpi_add_pm_notifier(dev, NULL, pci_acpi_wake_bus);
 459 }
 460
 461 /**
 462  * pci_acpi_add_pm_notifier - Register PM notifier for given PCI device.
 463  * @dev: ACPI device to add the notifier for.
 464  * @pci_dev: PCI device to check for the PME status if an event is signaled.
 465  */
 466 acpi_status pci_acpi_add_pm_notifier(struct acpi_device *dev,
 467                                      struct pci_dev *pci_dev)
 468 {
 469         return acpi_add_pm_notifier(dev, &pci_dev->dev, pci_acpi_wake_dev);
 470 }
 471
 472 /*
 473  * _SxD returns the D-state with the highest power
 474  * (lowest D-state number) supported in the S-state "x".
 475  *
 476  * If the devices does not have a _PRW
 477  * (Power Resources for Wake) supporting system wakeup from "x"
 478  * then the OS is free to choose a lower power (higher number
 479  * D-state) than the return value from _SxD.
 480  *
 481  * But if _PRW is enabled at S-state "x", the OS
 482  * must not choose a power lower than _SxD --
 483  * unless the device has an _SxW method specifying
 484  * the lowest power (highest D-state number) the device
 485  * may enter while still able to wake the system.
 486  *
 487  * ie. depending on global OS policy:
 488  *
 489  * if (_PRW at S-state x)
 490  *      choose from highest power _SxD to lowest power _SxW
 491  * else // no _PRW at S-state x
 492  *      choose highest power _SxD or any lower power
 493  */
 494
 495 static pci_power_t acpi_pci_choose_state(struct pci_dev *pdev)
 496 {
 497         int acpi_state, d_max;
 498
 499         if (pdev->no_d3cold)
 500                 d_max = ACPI_STATE_D3_HOT;
 501         else
 502                 d_max = ACPI_STATE_D3_COLD;
 503         acpi_state = acpi_pm_device_sleep_state(&pdev->dev, NULL, d_max);
 504         if (acpi_state < 0)
 505                 return PCI_POWER_ERROR;
 506
 507         switch (acpi_state) {
 508         case ACPI_STATE_D0:
 509                 return PCI_D0;
 510         case ACPI_STATE_D1:
 511                 return PCI_D1;
 512         case ACPI_STATE_D2:
 513                 return PCI_D2;
 514         case ACPI_STATE_D3_HOT:
 515                 return PCI_D3hot;
 516         case ACPI_STATE_D3_COLD:
 517                 return PCI_D3cold;
 518         }
 519         return PCI_POWER_ERROR;
 520 }
 521
 522 static bool acpi_pci_power_manageable(struct pci_dev *dev)
 523 {
 524         struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
 525         return adev ? acpi_device_power_manageable(adev) : false;
 526 }
 527
 528 static int acpi_pci_set_power_state(struct pci_dev *dev, pci_power_t state)
 529 {
 530         struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
 531         static const u8 state_conv[] = {
 532                 [PCI_D0] = ACPI_STATE_D0,
 533                 [PCI_D1] = ACPI_STATE_D1,
 534                 [PCI_D2] = ACPI_STATE_D2,
 535                 [PCI_D3hot] = ACPI_STATE_D3_HOT,
 536                 [PCI_D3cold] = ACPI_STATE_D3_COLD,
 537         };
 538         int error = -EINVAL;
 539
 540         /* If the ACPI device has _EJ0, ignore the device */
 541         if (!adev || acpi_has_method(adev->handle, "_EJ0"))
 542                 return -ENODEV;
 543
 544         switch (state) {
 545         case PCI_D3cold:
 546                 if (dev_pm_qos_flags(&dev->dev, PM_QOS_FLAG_NO_POWER_OFF) ==
 547                                 PM_QOS_FLAGS_ALL) {
 548                         error = -EBUSY;
 549                         break;
 550                 }
 551         case PCI_D0:
 552         case PCI_D1:
 553         case PCI_D2:
 554         case PCI_D3hot:
 555                 error = acpi_device_set_power(adev, state_conv[state]);
 556         }
 557
 558         if (!error)
 559                 pci_dbg(dev, "power state changed by ACPI to %s\n",
 560                          acpi_power_state_string(state_conv[state]));
 561
 562         return error;
 563 }
 564
 565 static pci_power_t acpi_pci_get_power_state(struct pci_dev *dev)
 566 {
 567         struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
 568         static const pci_power_t state_conv[] = {
 569                 [ACPI_STATE_D0]      = PCI_D0,
 570                 [ACPI_STATE_D1]      = PCI_D1,
 571                 [ACPI_STATE_D2]      = PCI_D2,
 572                 [ACPI_STATE_D3_HOT]  = PCI_D3hot,
 573                 [ACPI_STATE_D3_COLD] = PCI_D3cold,
 574         };
 575         int state;
 576
 577         if (!adev || !acpi_device_power_manageable(adev))
 578                 return PCI_UNKNOWN;
 579
 580         if (acpi_device_get_power(adev, &state) || state == ACPI_STATE_UNKNOWN)
 581                 return PCI_UNKNOWN;
 582
 583         return state_conv[state];
 584 }
 585
 586 static int acpi_pci_propagate_wakeup(struct pci_bus *bus, bool enable)
 587 {
 588         while (bus->parent) {
 589                 if (acpi_pm_device_can_wakeup(&bus->self->dev))
 590                         return acpi_pm_set_bridge_wakeup(&bus->self->dev, enable);
 591
 592                 bus = bus->parent;
 593         }
 594
 595         /* We have reached the root bus. */
 596         if (bus->bridge) {
 597                 if (acpi_pm_device_can_wakeup(bus->bridge))
 598                         return acpi_pm_set_bridge_wakeup(bus->bridge, enable);
 599         }
 600         return 0;
 601 }
 602
 603 static int acpi_pci_wakeup(struct pci_dev *dev, bool enable)
 604 {
 605         if (acpi_pm_device_can_wakeup(&dev->dev))
 606                 return acpi_pm_set_device_wakeup(&dev->dev, enable);
 607
 608         return acpi_pci_propagate_wakeup(dev->bus, enable);
 609 }
 610
 611 static bool acpi_pci_need_resume(struct pci_dev *dev)
 612 {
 613         struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
 614
 615         /*
 616          * In some cases (eg. Samsung 305V4A) leaving a bridge in suspend over
 617          * system-wide suspend/resume confuses the platform firmware, so avoid
 618          * doing that.  According to Section 16.1.6 of ACPI 6.2, endpoint
 619          * devices are expected to be in D3 before invoking the S3 entry path
 620          * from the firmware, so they should not be affected by this issue.
 621          */
 622         if (pci_is_bridge(dev) && acpi_target_system_state() != ACPI_STATE_S0)
 623                 return true;
 624
 625         if (!adev || !acpi_device_power_manageable(adev))
 626                 return false;
 627
 628         if (device_may_wakeup(&dev->dev) != !!adev->wakeup.prepare_count)
 629                 return true;
 630
 631         if (acpi_target_system_state() == ACPI_STATE_S0)
 632                 return false;
 633
 634         return !!adev->power.flags.dsw_present;
 635 }
 636
 637 static const struct pci_platform_pm_ops acpi_pci_platform_pm = {
 638         .is_manageable = acpi_pci_power_manageable,
 639         .set_state = acpi_pci_set_power_state,
 640         .get_state = acpi_pci_get_power_state,
 641         .choose_state = acpi_pci_choose_state,
 642         .set_wakeup = acpi_pci_wakeup,
 643         .need_resume = acpi_pci_need_resume,
 644 };
 645
 646 void acpi_pci_add_bus(struct pci_bus *bus)
 647 {
 648         union acpi_object *obj;
 649         struct pci_host_bridge *bridge;
 650
 651         if (acpi_pci_disabled || !bus->bridge || !ACPI_HANDLE(bus->bridge))
 652                 return;
 653
 654         acpi_pci_slot_enumerate(bus);
 655         acpiphp_enumerate_slots(bus);
 656
 657         /*
 658          * For a host bridge, check its _DSM for function 8 and if
 659          * that is available, mark it in pci_host_bridge.
 660          */
 661         if (!pci_is_root_bus(bus))
 662                 return;
 663
 664         obj = acpi_evaluate_dsm(ACPI_HANDLE(bus->bridge), &pci_acpi_dsm_guid, 3,
 665                                 RESET_DELAY_DSM, NULL);
 666         if (!obj)
 667                 return;
 668
 669         if (obj->type == ACPI_TYPE_INTEGER && obj->integer.value == 1) {
 670                 bridge = pci_find_host_bridge(bus);
 671                 bridge->ignore_reset_delay = 1;
 672         }
 673         ACPI_FREE(obj);
 674 }
 675
 676 void acpi_pci_remove_bus(struct pci_bus *bus)
 677 {
 678         if (acpi_pci_disabled || !bus->bridge)
 679                 return;
 680
 681         acpiphp_remove_slots(bus);
 682         acpi_pci_slot_remove(bus);
 683 }
 684
 685 /* ACPI bus type */
 686 static struct acpi_device *acpi_pci_find_companion(struct device *dev)
 687 {
 688         struct pci_dev *pci_dev = to_pci_dev(dev);
 689         bool check_children;
 690         u64 addr;
 691
 692         check_children = pci_is_bridge(pci_dev);
 693         /* Please ref to ACPI spec for the syntax of _ADR */
 694         addr = (PCI_SLOT(pci_dev->devfn) << 16) | PCI_FUNC(pci_dev->devfn);
 695         return acpi_find_child_device(ACPI_COMPANION(dev->parent), addr,
 696                                       check_children);
 697 }
 698
 699 /**
 700  * pci_acpi_optimize_delay - optimize PCI D3 and D3cold delay from ACPI
 701  * @pdev: the PCI device whose delay is to be updated
 702  * @handle: ACPI handle of this device
 703  *
 704  * Update the d3_delay and d3cold_delay of a PCI device from the ACPI _DSM
 705  * control method of either the device itself or the PCI host bridge.
 706  *
 707  * Function 8, "Reset Delay," applies to the entire hierarchy below a PCI
 708  * host bridge.  If it returns one, the OS may assume that all devices in
 709  * the hierarchy have already completed power-on reset delays.
 710  *
 711  * Function 9, "Device Readiness Durations," applies only to the object
 712  * where it is located.  It returns delay durations required after various
 713  * events if the device requires less time than the spec requires.  Delays
 714  * from this function take precedence over the Reset Delay function.
 715  *
 716  * These _DSM functions are defined by the draft ECN of January 28, 2014,
 717  * titled "ACPI additions for FW latency optimizations."
 718  */
 719 static void pci_acpi_optimize_delay(struct pci_dev *pdev,
 720                                     acpi_handle handle)
 721 {
 722         struct pci_host_bridge *bridge = pci_find_host_bridge(pdev->bus);
 723         int value;
 724         union acpi_object *obj, *elements;
 725
 726         if (bridge->ignore_reset_delay)
 727                 pdev->d3cold_delay = 0;
 728
 729         obj = acpi_evaluate_dsm(handle, &pci_acpi_dsm_guid, 3,
 730                                 FUNCTION_DELAY_DSM, NULL);
 731         if (!obj)
 732                 return;
 733
 734         if (obj->type == ACPI_TYPE_PACKAGE && obj->package.count == 5) {
 735                 elements = obj->package.elements;
 736                 if (elements[0].type == ACPI_TYPE_INTEGER) {
 737                         value = (int)elements[0].integer.value / 1000;
 738                         if (value < PCI_PM_D3COLD_WAIT)
 739                                 pdev->d3cold_delay = value;
 740                 }
 741                 if (elements[3].type == ACPI_TYPE_INTEGER) {
 742                         value = (int)elements[3].integer.value / 1000;
 743                         if (value < PCI_PM_D3_WAIT)
 744                                 pdev->d3_delay = value;
 745                 }
 746         }
 747         ACPI_FREE(obj);
 748 }
 749
 750 static void pci_acpi_setup(struct device *dev)
 751 {
 752         struct pci_dev *pci_dev = to_pci_dev(dev);
 753         struct acpi_device *adev = ACPI_COMPANION(dev);
 754
 755         if (!adev)
 756                 return;
 757
 758         pci_acpi_optimize_delay(pci_dev, adev->handle);
 759
 760         pci_acpi_add_pm_notifier(adev, pci_dev);
 761         if (!adev->wakeup.flags.valid)
 762                 return;
 763
 764         device_set_wakeup_capable(dev, true);
 765         acpi_pci_wakeup(pci_dev, false);
 766 }
 767
 768 static void pci_acpi_cleanup(struct device *dev)
 769 {
 770         struct acpi_device *adev = ACPI_COMPANION(dev);
 771
 772         if (!adev)
 773                 return;
 774
 775         pci_acpi_remove_pm_notifier(adev);
 776         if (adev->wakeup.flags.valid)
 777                 device_set_wakeup_capable(dev, false);
 778 }
 779
 780 static bool pci_acpi_bus_match(struct device *dev)
 781 {
 782         return dev_is_pci(dev);
 783 }
 784
 785 static struct acpi_bus_type acpi_pci_bus = {
 786         .name = "PCI",
 787         .match = pci_acpi_bus_match,
 788         .find_companion = acpi_pci_find_companion,
 789         .setup = pci_acpi_setup,
 790         .cleanup = pci_acpi_cleanup,
 791 };
 792
 793
 794 static struct fwnode_handle *(*pci_msi_get_fwnode_cb)(struct device *dev);
 795
 796 /**
 797  * pci_msi_register_fwnode_provider - Register callback to retrieve fwnode
 798  * @fn:       Callback matching a device to a fwnode that identifies a PCI
 799  *            MSI domain.
 800  *
 801  * This should be called by irqchip driver, which is the parent of
 802  * the MSI domain to provide callback interface to query fwnode.
 803  */
 804 void
 805 pci_msi_register_fwnode_provider(struct fwnode_handle *(*fn)(struct device *))
 806 {
 807         pci_msi_get_fwnode_cb = fn;
 808 }
 809
 810 /**
 811  * pci_host_bridge_acpi_msi_domain - Retrieve MSI domain of a PCI host bridge
 812  * @bus:      The PCI host bridge bus.
 813  *
 814  * This function uses the callback function registered by
 815  * pci_msi_register_fwnode_provider() to retrieve the irq_domain with
 816  * type DOMAIN_BUS_PCI_MSI of the specified host bridge bus.
 817  * This returns NULL on error or when the domain is not found.
 818  */
 819 struct irq_domain *pci_host_bridge_acpi_msi_domain(struct pci_bus *bus)
 820 {
 821         struct fwnode_handle *fwnode;
 822
 823         if (!pci_msi_get_fwnode_cb)
 824                 return NULL;
 825
 826         fwnode = pci_msi_get_fwnode_cb(&bus->dev);
 827         if (!fwnode)
 828                 return NULL;
 829
 830         return irq_find_matching_fwnode(fwnode, DOMAIN_BUS_PCI_MSI);
 831 }
 832
 833 static int __init acpi_pci_init(void)
 834 {
 835         int ret;
 836
 837         if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_MSI) {
 838                 pr_info("ACPI FADT declares the system doesn't support MSI, so disable it\n");
 839                 pci_no_msi();
 840         }
 841
 842         if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) {
 843                 pr_info("ACPI FADT declares the system doesn't support PCIe ASPM, so disable it\n");
 844                 pcie_no_aspm();
 845         }
 846
 847         ret = register_acpi_bus_type(&acpi_pci_bus);
 848         if (ret)
 849                 return 0;
 850
 851         pci_set_platform_pm(&acpi_pci_platform_pm);
 852         acpi_pci_slot_init();
 853         acpiphp_init();
 854
 855         return 0;
 856 }
 857 arch_initcall(acpi_pci_init);