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 const struct pci_host_bridge *host; 407 408 if (!IS_ENABLED(CONFIG_HOTPLUG_PCI_SHPC)) 409 return false; 410 411 /* 412 * It is assumed that AMD GOLAM chips support SHPC but they do not 413 * have SHPC capability. 414 */ 415 if (bridge->vendor == PCI_VENDOR_ID_AMD && 416 bridge->device == PCI_DEVICE_ID_AMD_GOLAM_7450) 417 return true; 418 419 if (!pci_find_capability(bridge, PCI_CAP_ID_SHPC)) 420 return false; 421 422 host = pci_find_host_bridge(bridge->bus); 423 return host->native_shpc_hotplug; 424 } 425 426 /** 427 * pci_acpi_wake_bus - Root bus wakeup notification fork function. 428 * @context: Device wakeup context. 429 */ 430 static void pci_acpi_wake_bus(struct acpi_device_wakeup_context *context) 431 { 432 struct acpi_device *adev; 433 struct acpi_pci_root *root; 434 435 adev = container_of(context, struct acpi_device, wakeup.context); 436 root = acpi_driver_data(adev); 437 pci_pme_wakeup_bus(root->bus); 438 } 439 440 /** 441 * pci_acpi_wake_dev - PCI device wakeup notification work function. 442 * @context: Device wakeup context. 443 */ 444 static void pci_acpi_wake_dev(struct acpi_device_wakeup_context *context) 445 { 446 struct pci_dev *pci_dev; 447 448 pci_dev = to_pci_dev(context->dev); 449 450 if (pci_dev->pme_poll) 451 pci_dev->pme_poll = false; 452 453 if (pci_dev->current_state == PCI_D3cold) { 454 pci_wakeup_event(pci_dev); 455 pm_request_resume(&pci_dev->dev); 456 return; 457 } 458 459 /* Clear PME Status if set. */ 460 if (pci_dev->pme_support) 461 pci_check_pme_status(pci_dev); 462 463 pci_wakeup_event(pci_dev); 464 pm_request_resume(&pci_dev->dev); 465 466 pci_pme_wakeup_bus(pci_dev->subordinate); 467 } 468 469 /** 470 * pci_acpi_add_bus_pm_notifier - Register PM notifier for root PCI bus. 471 * @dev: PCI root bridge ACPI device. 472 */ 473 acpi_status pci_acpi_add_bus_pm_notifier(struct acpi_device *dev) 474 { 475 return acpi_add_pm_notifier(dev, NULL, pci_acpi_wake_bus); 476 } 477 478 /** 479 * pci_acpi_add_pm_notifier - Register PM notifier for given PCI device. 480 * @dev: ACPI device to add the notifier for. 481 * @pci_dev: PCI device to check for the PME status if an event is signaled. 482 */ 483 acpi_status pci_acpi_add_pm_notifier(struct acpi_device *dev, 484 struct pci_dev *pci_dev) 485 { 486 return acpi_add_pm_notifier(dev, &pci_dev->dev, pci_acpi_wake_dev); 487 } 488 489 /* 490 * _SxD returns the D-state with the highest power 491 * (lowest D-state number) supported in the S-state "x". 492 * 493 * If the devices does not have a _PRW 494 * (Power Resources for Wake) supporting system wakeup from "x" 495 * then the OS is free to choose a lower power (higher number 496 * D-state) than the return value from _SxD. 497 * 498 * But if _PRW is enabled at S-state "x", the OS 499 * must not choose a power lower than _SxD -- 500 * unless the device has an _SxW method specifying 501 * the lowest power (highest D-state number) the device 502 * may enter while still able to wake the system. 503 * 504 * ie. depending on global OS policy: 505 * 506 * if (_PRW at S-state x) 507 * choose from highest power _SxD to lowest power _SxW 508 * else // no _PRW at S-state x 509 * choose highest power _SxD or any lower power 510 */ 511 512 static pci_power_t acpi_pci_choose_state(struct pci_dev *pdev) 513 { 514 int acpi_state, d_max; 515 516 if (pdev->no_d3cold) 517 d_max = ACPI_STATE_D3_HOT; 518 else 519 d_max = ACPI_STATE_D3_COLD; 520 acpi_state = acpi_pm_device_sleep_state(&pdev->dev, NULL, d_max); 521 if (acpi_state < 0) 522 return PCI_POWER_ERROR; 523 524 switch (acpi_state) { 525 case ACPI_STATE_D0: 526 return PCI_D0; 527 case ACPI_STATE_D1: 528 return PCI_D1; 529 case ACPI_STATE_D2: 530 return PCI_D2; 531 case ACPI_STATE_D3_HOT: 532 return PCI_D3hot; 533 case ACPI_STATE_D3_COLD: 534 return PCI_D3cold; 535 } 536 return PCI_POWER_ERROR; 537 } 538 539 static bool acpi_pci_power_manageable(struct pci_dev *dev) 540 { 541 struct acpi_device *adev = ACPI_COMPANION(&dev->dev); 542 return adev ? acpi_device_power_manageable(adev) : false; 543 } 544 545 static int acpi_pci_set_power_state(struct pci_dev *dev, pci_power_t state) 546 { 547 struct acpi_device *adev = ACPI_COMPANION(&dev->dev); 548 static const u8 state_conv[] = { 549 [PCI_D0] = ACPI_STATE_D0, 550 [PCI_D1] = ACPI_STATE_D1, 551 [PCI_D2] = ACPI_STATE_D2, 552 [PCI_D3hot] = ACPI_STATE_D3_HOT, 553 [PCI_D3cold] = ACPI_STATE_D3_COLD, 554 }; 555 int error = -EINVAL; 556 557 /* If the ACPI device has _EJ0, ignore the device */ 558 if (!adev || acpi_has_method(adev->handle, "_EJ0")) 559 return -ENODEV; 560 561 switch (state) { 562 case PCI_D3cold: 563 if (dev_pm_qos_flags(&dev->dev, PM_QOS_FLAG_NO_POWER_OFF) == 564 PM_QOS_FLAGS_ALL) { 565 error = -EBUSY; 566 break; 567 } 568 case PCI_D0: 569 case PCI_D1: 570 case PCI_D2: 571 case PCI_D3hot: 572 error = acpi_device_set_power(adev, state_conv[state]); 573 } 574 575 if (!error) 576 pci_dbg(dev, "power state changed by ACPI to %s\n", 577 acpi_power_state_string(state_conv[state])); 578 579 return error; 580 } 581 582 static pci_power_t acpi_pci_get_power_state(struct pci_dev *dev) 583 { 584 struct acpi_device *adev = ACPI_COMPANION(&dev->dev); 585 static const pci_power_t state_conv[] = { 586 [ACPI_STATE_D0] = PCI_D0, 587 [ACPI_STATE_D1] = PCI_D1, 588 [ACPI_STATE_D2] = PCI_D2, 589 [ACPI_STATE_D3_HOT] = PCI_D3hot, 590 [ACPI_STATE_D3_COLD] = PCI_D3cold, 591 }; 592 int state; 593 594 if (!adev || !acpi_device_power_manageable(adev)) 595 return PCI_UNKNOWN; 596 597 if (acpi_device_get_power(adev, &state) || state == ACPI_STATE_UNKNOWN) 598 return PCI_UNKNOWN; 599 600 return state_conv[state]; 601 } 602 603 static int acpi_pci_propagate_wakeup(struct pci_bus *bus, bool enable) 604 { 605 while (bus->parent) { 606 if (acpi_pm_device_can_wakeup(&bus->self->dev)) 607 return acpi_pm_set_bridge_wakeup(&bus->self->dev, enable); 608 609 bus = bus->parent; 610 } 611 612 /* We have reached the root bus. */ 613 if (bus->bridge) { 614 if (acpi_pm_device_can_wakeup(bus->bridge)) 615 return acpi_pm_set_bridge_wakeup(bus->bridge, enable); 616 } 617 return 0; 618 } 619 620 static int acpi_pci_wakeup(struct pci_dev *dev, bool enable) 621 { 622 if (acpi_pm_device_can_wakeup(&dev->dev)) 623 return acpi_pm_set_device_wakeup(&dev->dev, enable); 624 625 return acpi_pci_propagate_wakeup(dev->bus, enable); 626 } 627 628 static bool acpi_pci_need_resume(struct pci_dev *dev) 629 { 630 struct acpi_device *adev = ACPI_COMPANION(&dev->dev); 631 632 if (!adev || !acpi_device_power_manageable(adev)) 633 return false; 634 635 if (device_may_wakeup(&dev->dev) != !!adev->wakeup.prepare_count) 636 return true; 637 638 if (acpi_target_system_state() == ACPI_STATE_S0) 639 return false; 640 641 return !!adev->power.flags.dsw_present; 642 } 643 644 static const struct pci_platform_pm_ops acpi_pci_platform_pm = { 645 .is_manageable = acpi_pci_power_manageable, 646 .set_state = acpi_pci_set_power_state, 647 .get_state = acpi_pci_get_power_state, 648 .choose_state = acpi_pci_choose_state, 649 .set_wakeup = acpi_pci_wakeup, 650 .need_resume = acpi_pci_need_resume, 651 }; 652 653 void acpi_pci_add_bus(struct pci_bus *bus) 654 { 655 union acpi_object *obj; 656 struct pci_host_bridge *bridge; 657 658 if (acpi_pci_disabled || !bus->bridge || !ACPI_HANDLE(bus->bridge)) 659 return; 660 661 acpi_pci_slot_enumerate(bus); 662 acpiphp_enumerate_slots(bus); 663 664 /* 665 * For a host bridge, check its _DSM for function 8 and if 666 * that is available, mark it in pci_host_bridge. 667 */ 668 if (!pci_is_root_bus(bus)) 669 return; 670 671 obj = acpi_evaluate_dsm(ACPI_HANDLE(bus->bridge), &pci_acpi_dsm_guid, 3, 672 RESET_DELAY_DSM, NULL); 673 if (!obj) 674 return; 675 676 if (obj->type == ACPI_TYPE_INTEGER && obj->integer.value == 1) { 677 bridge = pci_find_host_bridge(bus); 678 bridge->ignore_reset_delay = 1; 679 } 680 ACPI_FREE(obj); 681 } 682 683 void acpi_pci_remove_bus(struct pci_bus *bus) 684 { 685 if (acpi_pci_disabled || !bus->bridge) 686 return; 687 688 acpiphp_remove_slots(bus); 689 acpi_pci_slot_remove(bus); 690 } 691 692 /* ACPI bus type */ 693 static struct acpi_device *acpi_pci_find_companion(struct device *dev) 694 { 695 struct pci_dev *pci_dev = to_pci_dev(dev); 696 bool check_children; 697 u64 addr; 698 699 check_children = pci_is_bridge(pci_dev); 700 /* Please ref to ACPI spec for the syntax of _ADR */ 701 addr = (PCI_SLOT(pci_dev->devfn) << 16) | PCI_FUNC(pci_dev->devfn); 702 return acpi_find_child_device(ACPI_COMPANION(dev->parent), addr, 703 check_children); 704 } 705 706 /** 707 * pci_acpi_optimize_delay - optimize PCI D3 and D3cold delay from ACPI 708 * @pdev: the PCI device whose delay is to be updated 709 * @handle: ACPI handle of this device 710 * 711 * Update the d3_delay and d3cold_delay of a PCI device from the ACPI _DSM 712 * control method of either the device itself or the PCI host bridge. 713 * 714 * Function 8, "Reset Delay," applies to the entire hierarchy below a PCI 715 * host bridge. If it returns one, the OS may assume that all devices in 716 * the hierarchy have already completed power-on reset delays. 717 * 718 * Function 9, "Device Readiness Durations," applies only to the object 719 * where it is located. It returns delay durations required after various 720 * events if the device requires less time than the spec requires. Delays 721 * from this function take precedence over the Reset Delay function. 722 * 723 * These _DSM functions are defined by the draft ECN of January 28, 2014, 724 * titled "ACPI additions for FW latency optimizations." 725 */ 726 static void pci_acpi_optimize_delay(struct pci_dev *pdev, 727 acpi_handle handle) 728 { 729 struct pci_host_bridge *bridge = pci_find_host_bridge(pdev->bus); 730 int value; 731 union acpi_object *obj, *elements; 732 733 if (bridge->ignore_reset_delay) 734 pdev->d3cold_delay = 0; 735 736 obj = acpi_evaluate_dsm(handle, &pci_acpi_dsm_guid, 3, 737 FUNCTION_DELAY_DSM, NULL); 738 if (!obj) 739 return; 740 741 if (obj->type == ACPI_TYPE_PACKAGE && obj->package.count == 5) { 742 elements = obj->package.elements; 743 if (elements[0].type == ACPI_TYPE_INTEGER) { 744 value = (int)elements[0].integer.value / 1000; 745 if (value < PCI_PM_D3COLD_WAIT) 746 pdev->d3cold_delay = value; 747 } 748 if (elements[3].type == ACPI_TYPE_INTEGER) { 749 value = (int)elements[3].integer.value / 1000; 750 if (value < PCI_PM_D3_WAIT) 751 pdev->d3_delay = value; 752 } 753 } 754 ACPI_FREE(obj); 755 } 756 757 static void pci_acpi_setup(struct device *dev) 758 { 759 struct pci_dev *pci_dev = to_pci_dev(dev); 760 struct acpi_device *adev = ACPI_COMPANION(dev); 761 762 if (!adev) 763 return; 764 765 pci_acpi_optimize_delay(pci_dev, adev->handle); 766 767 pci_acpi_add_pm_notifier(adev, pci_dev); 768 if (!adev->wakeup.flags.valid) 769 return; 770 771 device_set_wakeup_capable(dev, true); 772 acpi_pci_wakeup(pci_dev, false); 773 } 774 775 static void pci_acpi_cleanup(struct device *dev) 776 { 777 struct acpi_device *adev = ACPI_COMPANION(dev); 778 779 if (!adev) 780 return; 781 782 pci_acpi_remove_pm_notifier(adev); 783 if (adev->wakeup.flags.valid) 784 device_set_wakeup_capable(dev, false); 785 } 786 787 static bool pci_acpi_bus_match(struct device *dev) 788 { 789 return dev_is_pci(dev); 790 } 791 792 static struct acpi_bus_type acpi_pci_bus = { 793 .name = "PCI", 794 .match = pci_acpi_bus_match, 795 .find_companion = acpi_pci_find_companion, 796 .setup = pci_acpi_setup, 797 .cleanup = pci_acpi_cleanup, 798 }; 799 800 801 static struct fwnode_handle *(*pci_msi_get_fwnode_cb)(struct device *dev); 802 803 /** 804 * pci_msi_register_fwnode_provider - Register callback to retrieve fwnode 805 * @fn: Callback matching a device to a fwnode that identifies a PCI 806 * MSI domain. 807 * 808 * This should be called by irqchip driver, which is the parent of 809 * the MSI domain to provide callback interface to query fwnode. 810 */ 811 void 812 pci_msi_register_fwnode_provider(struct fwnode_handle *(*fn)(struct device *)) 813 { 814 pci_msi_get_fwnode_cb = fn; 815 } 816 817 /** 818 * pci_host_bridge_acpi_msi_domain - Retrieve MSI domain of a PCI host bridge 819 * @bus: The PCI host bridge bus. 820 * 821 * This function uses the callback function registered by 822 * pci_msi_register_fwnode_provider() to retrieve the irq_domain with 823 * type DOMAIN_BUS_PCI_MSI of the specified host bridge bus. 824 * This returns NULL on error or when the domain is not found. 825 */ 826 struct irq_domain *pci_host_bridge_acpi_msi_domain(struct pci_bus *bus) 827 { 828 struct fwnode_handle *fwnode; 829 830 if (!pci_msi_get_fwnode_cb) 831 return NULL; 832 833 fwnode = pci_msi_get_fwnode_cb(&bus->dev); 834 if (!fwnode) 835 return NULL; 836 837 return irq_find_matching_fwnode(fwnode, DOMAIN_BUS_PCI_MSI); 838 } 839 840 static int __init acpi_pci_init(void) 841 { 842 int ret; 843 844 if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_MSI) { 845 pr_info("ACPI FADT declares the system doesn't support MSI, so disable it\n"); 846 pci_no_msi(); 847 } 848 849 if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) { 850 pr_info("ACPI FADT declares the system doesn't support PCIe ASPM, so disable it\n"); 851 pcie_no_aspm(); 852 } 853 854 ret = register_acpi_bus_type(&acpi_pci_bus); 855 if (ret) 856 return 0; 857 858 pci_set_platform_pm(&acpi_pci_platform_pm); 859 acpi_pci_slot_init(); 860 acpiphp_init(); 861 862 return 0; 863 } 864 arch_initcall(acpi_pci_init); 865