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/dmar.h>
  19 #include <linux/acpi.h>
  20 #include <linux/slab.h>
  21 #include <linux/dmi.h>
  22 #include <linux/platform_data/x86/apple.h>
  23 #include <acpi/apei.h>  /* for acpi_hest_init() */
  24
  25 #include "internal.h"
  26
  27 #define ACPI_PCI_ROOT_CLASS             "pci_bridge"
  28 #define ACPI_PCI_ROOT_DEVICE_NAME       "PCI Root Bridge"
  29 static int acpi_pci_root_add(struct acpi_device *device,
  30                              const struct acpi_device_id *not_used);
  31 static void acpi_pci_root_remove(struct acpi_device *device);
  32
  33 static int acpi_pci_root_scan_dependent(struct acpi_device *adev)
  34 {
  35         acpiphp_check_host_bridge(adev);
  36         return 0;
  37 }
  38
  39 #define ACPI_PCIE_REQ_SUPPORT (OSC_PCI_EXT_CONFIG_SUPPORT \
  40                                 | OSC_PCI_ASPM_SUPPORT \
  41                                 | OSC_PCI_CLOCK_PM_SUPPORT \
  42                                 | OSC_PCI_MSI_SUPPORT)
  43
  44 static const struct acpi_device_id root_device_ids[] = {
  45         {"PNP0A03", 0},
  46         {"", 0},
  47 };
  48
  49 static struct acpi_scan_handler pci_root_handler = {
  50         .ids = root_device_ids,
  51         .attach = acpi_pci_root_add,
  52         .detach = acpi_pci_root_remove,
  53         .hotplug = {
  54                 .enabled = true,
  55                 .scan_dependent = acpi_pci_root_scan_dependent,
  56         },
  57 };
  58
  59 static DEFINE_MUTEX(osc_lock);
  60
  61 /**
  62  * acpi_is_root_bridge - determine whether an ACPI CA node is a PCI root bridge
  63  * @handle:  the ACPI CA node in question.
  64  *
  65  * Note: we could make this API take a struct acpi_device * instead, but
  66  * for now, it's more convenient to operate on an acpi_handle.
  67  */
  68 int acpi_is_root_bridge(acpi_handle handle)
  69 {
  70         int ret;
  71         struct acpi_device *device;
  72
  73         ret = acpi_bus_get_device(handle, &device);
  74         if (ret)
  75                 return 0;
  76
  77         ret = acpi_match_device_ids(device, root_device_ids);
  78         if (ret)
  79                 return 0;
  80         else
  81                 return 1;
  82 }
  83 EXPORT_SYMBOL_GPL(acpi_is_root_bridge);
  84
  85 static acpi_status
  86 get_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
  87 {
  88         struct resource *res = data;
  89         struct acpi_resource_address64 address;
  90         acpi_status status;
  91
  92         status = acpi_resource_to_address64(resource, &address);
  93         if (ACPI_FAILURE(status))
  94                 return AE_OK;
  95
  96         if ((address.address.address_length > 0) &&
  97             (address.resource_type == ACPI_BUS_NUMBER_RANGE)) {
  98                 res->start = address.address.minimum;
  99                 res->end = address.address.minimum + address.address.address_length - 1;
 100         }
 101
 102         return AE_OK;
 103 }
 104
 105 static acpi_status try_get_root_bridge_busnr(acpi_handle handle,
 106                                              struct resource *res)
 107 {
 108         acpi_status status;
 109
 110         res->start = -1;
 111         status =
 112             acpi_walk_resources(handle, METHOD_NAME__CRS,
 113                                 get_root_bridge_busnr_callback, res);
 114         if (ACPI_FAILURE(status))
 115                 return status;
 116         if (res->start == -1)
 117                 return AE_ERROR;
 118         return AE_OK;
 119 }
 120
 121 struct pci_osc_bit_struct {
 122         u32 bit;
 123         char *desc;
 124 };
 125
 126 static struct pci_osc_bit_struct pci_osc_support_bit[] = {
 127         { OSC_PCI_EXT_CONFIG_SUPPORT, "ExtendedConfig" },
 128         { OSC_PCI_ASPM_SUPPORT, "ASPM" },
 129         { OSC_PCI_CLOCK_PM_SUPPORT, "ClockPM" },
 130         { OSC_PCI_SEGMENT_GROUPS_SUPPORT, "Segments" },
 131         { OSC_PCI_MSI_SUPPORT, "MSI" },
 132         { OSC_PCI_EDR_SUPPORT, "EDR" },
 133         { OSC_PCI_HPX_TYPE_3_SUPPORT, "HPX-Type3" },
 134 };
 135
 136 static struct pci_osc_bit_struct pci_osc_control_bit[] = {
 137         { OSC_PCI_EXPRESS_NATIVE_HP_CONTROL, "PCIeHotplug" },
 138         { OSC_PCI_SHPC_NATIVE_HP_CONTROL, "SHPCHotplug" },
 139         { OSC_PCI_EXPRESS_PME_CONTROL, "PME" },
 140         { OSC_PCI_EXPRESS_AER_CONTROL, "AER" },
 141         { OSC_PCI_EXPRESS_CAPABILITY_CONTROL, "PCIeCapability" },
 142         { OSC_PCI_EXPRESS_LTR_CONTROL, "LTR" },
 143         { OSC_PCI_EXPRESS_DPC_CONTROL, "DPC" },
 144 };
 145
 146 static void decode_osc_bits(struct acpi_pci_root *root, char *msg, u32 word,
 147                             struct pci_osc_bit_struct *table, int size)
 148 {
 149         char buf[80];
 150         int i, len = 0;
 151         struct pci_osc_bit_struct *entry;
 152
 153         buf[0] = '\0';
 154         for (i = 0, entry = table; i < size; i++, entry++)
 155                 if (word & entry->bit)
 156                         len += scnprintf(buf + len, sizeof(buf) - len, "%s%s",
 157                                         len ? " " : "", entry->desc);
 158
 159         dev_info(&root->device->dev, "_OSC: %s [%s]\n", msg, buf);
 160 }
 161
 162 static void decode_osc_support(struct acpi_pci_root *root, char *msg, u32 word)
 163 {
 164         decode_osc_bits(root, msg, word, pci_osc_support_bit,
 165                         ARRAY_SIZE(pci_osc_support_bit));
 166 }
 167
 168 static void decode_osc_control(struct acpi_pci_root *root, char *msg, u32 word)
 169 {
 170         decode_osc_bits(root, msg, word, pci_osc_control_bit,
 171                         ARRAY_SIZE(pci_osc_control_bit));
 172 }
 173
 174 static u8 pci_osc_uuid_str[] = "33DB4D5B-1FF7-401C-9657-7441C03DD766";
 175
 176 static acpi_status acpi_pci_run_osc(acpi_handle handle,
 177                                     const u32 *capbuf, u32 *retval)
 178 {
 179         struct acpi_osc_context context = {
 180                 .uuid_str = pci_osc_uuid_str,
 181                 .rev = 1,
 182                 .cap.length = 12,
 183                 .cap.pointer = (void *)capbuf,
 184         };
 185         acpi_status status;
 186
 187         status = acpi_run_osc(handle, &context);
 188         if (ACPI_SUCCESS(status)) {
 189                 *retval = *((u32 *)(context.ret.pointer + 8));
 190                 kfree(context.ret.pointer);
 191         }
 192         return status;
 193 }
 194
 195 static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root,
 196                                         u32 support,
 197                                         u32 *control)
 198 {
 199         acpi_status status;
 200         u32 result, capbuf[3];
 201
 202         support &= OSC_PCI_SUPPORT_MASKS;
 203         support |= root->osc_support_set;
 204
 205         capbuf[OSC_QUERY_DWORD] = OSC_QUERY_ENABLE;
 206         capbuf[OSC_SUPPORT_DWORD] = support;
 207         if (control) {
 208                 *control &= OSC_PCI_CONTROL_MASKS;
 209                 capbuf[OSC_CONTROL_DWORD] = *control | root->osc_control_set;
 210         } else {
 211                 /* Run _OSC query only with existing controls. */
 212                 capbuf[OSC_CONTROL_DWORD] = root->osc_control_set;
 213         }
 214
 215         status = acpi_pci_run_osc(root->device->handle, capbuf, &result);
 216         if (ACPI_SUCCESS(status)) {
 217                 root->osc_support_set = support;
 218                 if (control)
 219                         *control = result;
 220         }
 221         return status;
 222 }
 223
 224 static acpi_status acpi_pci_osc_support(struct acpi_pci_root *root, u32 flags)
 225 {
 226         acpi_status status;
 227
 228         mutex_lock(&osc_lock);
 229         status = acpi_pci_query_osc(root, flags, NULL);
 230         mutex_unlock(&osc_lock);
 231         return status;
 232 }
 233
 234 struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle)
 235 {
 236         struct acpi_pci_root *root;
 237         struct acpi_device *device;
 238
 239         if (acpi_bus_get_device(handle, &device) ||
 240             acpi_match_device_ids(device, root_device_ids))
 241                 return NULL;
 242
 243         root = acpi_driver_data(device);
 244
 245         return root;
 246 }
 247 EXPORT_SYMBOL_GPL(acpi_pci_find_root);
 248
 249 struct acpi_handle_node {
 250         struct list_head node;
 251         acpi_handle handle;
 252 };
 253
 254 /**
 255  * acpi_get_pci_dev - convert ACPI CA handle to struct pci_dev
 256  * @handle: the handle in question
 257  *
 258  * Given an ACPI CA handle, the desired PCI device is located in the
 259  * list of PCI devices.
 260  *
 261  * If the device is found, its reference count is increased and this
 262  * function returns a pointer to its data structure.  The caller must
 263  * decrement the reference count by calling pci_dev_put().
 264  * If no device is found, %NULL is returned.
 265  */
 266 struct pci_dev *acpi_get_pci_dev(acpi_handle handle)
 267 {
 268         int dev, fn;
 269         unsigned long long adr;
 270         acpi_status status;
 271         acpi_handle phandle;
 272         struct pci_bus *pbus;
 273         struct pci_dev *pdev = NULL;
 274         struct acpi_handle_node *node, *tmp;
 275         struct acpi_pci_root *root;
 276         LIST_HEAD(device_list);
 277
 278         /*
 279          * Walk up the ACPI CA namespace until we reach a PCI root bridge.
 280          */
 281         phandle = handle;
 282         while (!acpi_is_root_bridge(phandle)) {
 283                 node = kzalloc(sizeof(struct acpi_handle_node), GFP_KERNEL);
 284                 if (!node)
 285                         goto out;
 286
 287                 INIT_LIST_HEAD(&node->node);
 288                 node->handle = phandle;
 289                 list_add(&node->node, &device_list);
 290
 291                 status = acpi_get_parent(phandle, &phandle);
 292                 if (ACPI_FAILURE(status))
 293                         goto out;
 294         }
 295
 296         root = acpi_pci_find_root(phandle);
 297         if (!root)
 298                 goto out;
 299
 300         pbus = root->bus;
 301
 302         /*
 303          * Now, walk back down the PCI device tree until we return to our
 304          * original handle. Assumes that everything between the PCI root
 305          * bridge and the device we're looking for must be a P2P bridge.
 306          */
 307         list_for_each_entry(node, &device_list, node) {
 308                 acpi_handle hnd = node->handle;
 309                 status = acpi_evaluate_integer(hnd, "_ADR", NULL, &adr);
 310                 if (ACPI_FAILURE(status))
 311                         goto out;
 312                 dev = (adr >> 16) & 0xffff;
 313                 fn  = adr & 0xffff;
 314
 315                 pdev = pci_get_slot(pbus, PCI_DEVFN(dev, fn));
 316                 if (!pdev || hnd == handle)
 317                         break;
 318
 319                 pbus = pdev->subordinate;
 320                 pci_dev_put(pdev);
 321
 322                 /*
 323                  * This function may be called for a non-PCI device that has a
 324                  * PCI parent (eg. a disk under a PCI SATA controller).  In that
 325                  * case pdev->subordinate will be NULL for the parent.
 326                  */
 327                 if (!pbus) {
 328                         dev_dbg(&pdev->dev, "Not a PCI-to-PCI bridge\n");
 329                         pdev = NULL;
 330                         break;
 331                 }
 332         }
 333 out:
 334         list_for_each_entry_safe(node, tmp, &device_list, node)
 335                 kfree(node);
 336
 337         return pdev;
 338 }
 339 EXPORT_SYMBOL_GPL(acpi_get_pci_dev);
 340
 341 /**
 342  * acpi_pci_osc_control_set - Request control of PCI root _OSC features.
 343  * @handle: ACPI handle of a PCI root bridge (or PCIe Root Complex).
 344  * @mask: Mask of _OSC bits to request control of, place to store control mask.
 345  * @req: Mask of _OSC bits the control of is essential to the caller.
 346  *
 347  * Run _OSC query for @mask and if that is successful, compare the returned
 348  * mask of control bits with @req.  If all of the @req bits are set in the
 349  * returned mask, run _OSC request for it.
 350  *
 351  * The variable at the @mask address may be modified regardless of whether or
 352  * not the function returns success.  On success it will contain the mask of
 353  * _OSC bits the BIOS has granted control of, but its contents are meaningless
 354  * on failure.
 355  **/
 356 acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 *mask, u32 req)
 357 {
 358         struct acpi_pci_root *root;
 359         acpi_status status = AE_OK;
 360         u32 ctrl, capbuf[3];
 361
 362         if (!mask)
 363                 return AE_BAD_PARAMETER;
 364
 365         ctrl = *mask & OSC_PCI_CONTROL_MASKS;
 366         if ((ctrl & req) != req)
 367                 return AE_TYPE;
 368
 369         root = acpi_pci_find_root(handle);
 370         if (!root)
 371                 return AE_NOT_EXIST;
 372
 373         mutex_lock(&osc_lock);
 374
 375         *mask = ctrl | root->osc_control_set;
 376         /* No need to evaluate _OSC if the control was already granted. */
 377         if ((root->osc_control_set & ctrl) == ctrl)
 378                 goto out;
 379
 380         /* Need to check the available controls bits before requesting them. */
 381         while (*mask) {
 382                 status = acpi_pci_query_osc(root, root->osc_support_set, mask);
 383                 if (ACPI_FAILURE(status))
 384                         goto out;
 385                 if (ctrl == *mask)
 386                         break;
 387                 decode_osc_control(root, "platform does not support",
 388                                    ctrl & ~(*mask));
 389                 ctrl = *mask;
 390         }
 391
 392         if ((ctrl & req) != req) {
 393                 decode_osc_control(root, "not requesting control; platform does not support",
 394                                    req & ~(ctrl));
 395                 status = AE_SUPPORT;
 396                 goto out;
 397         }
 398
 399         capbuf[OSC_QUERY_DWORD] = 0;
 400         capbuf[OSC_SUPPORT_DWORD] = root->osc_support_set;
 401         capbuf[OSC_CONTROL_DWORD] = ctrl;
 402         status = acpi_pci_run_osc(handle, capbuf, mask);
 403         if (ACPI_SUCCESS(status))
 404                 root->osc_control_set = *mask;
 405 out:
 406         mutex_unlock(&osc_lock);
 407         return status;
 408 }
 409 EXPORT_SYMBOL(acpi_pci_osc_control_set);
 410
 411 static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm,
 412                                  bool is_pcie)
 413 {
 414         u32 support, control, requested;
 415         acpi_status status;
 416         struct acpi_device *device = root->device;
 417         acpi_handle handle = device->handle;
 418
 419         /*
 420          * Apple always return failure on _OSC calls when _OSI("Darwin") has
 421          * been called successfully. We know the feature set supported by the
 422          * platform, so avoid calling _OSC at all
 423          */
 424         if (x86_apple_machine) {
 425                 root->osc_control_set = ~OSC_PCI_EXPRESS_PME_CONTROL;
 426                 decode_osc_control(root, "OS assumes control of",
 427                                    root->osc_control_set);
 428                 return;
 429         }
 430
 431         /*
 432          * All supported architectures that use ACPI have support for
 433          * PCI domains, so we indicate this in _OSC support capabilities.
 434          */
 435         support = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
 436         support |= OSC_PCI_HPX_TYPE_3_SUPPORT;
 437         if (pci_ext_cfg_avail())
 438                 support |= OSC_PCI_EXT_CONFIG_SUPPORT;
 439         if (pcie_aspm_support_enabled())
 440                 support |= OSC_PCI_ASPM_SUPPORT | OSC_PCI_CLOCK_PM_SUPPORT;
 441         if (pci_msi_enabled())
 442                 support |= OSC_PCI_MSI_SUPPORT;
 443         if (IS_ENABLED(CONFIG_PCIE_EDR))
 444                 support |= OSC_PCI_EDR_SUPPORT;
 445
 446         decode_osc_support(root, "OS supports", support);
 447         status = acpi_pci_osc_support(root, support);
 448         if (ACPI_FAILURE(status)) {
 449                 *no_aspm = 1;
 450
 451                 /* _OSC is optional for PCI host bridges */
 452                 if ((status == AE_NOT_FOUND) && !is_pcie)
 453                         return;
 454
 455                 dev_info(&device->dev, "_OSC failed (%s)%s\n",
 456                          acpi_format_exception(status),
 457                          pcie_aspm_support_enabled() ? "; disabling ASPM" : "");
 458                 return;
 459         }
 460
 461         if (pcie_ports_disabled) {
 462                 dev_info(&device->dev, "PCIe port services disabled; not requesting _OSC control\n");
 463                 return;
 464         }
 465
 466         if ((support & ACPI_PCIE_REQ_SUPPORT) != ACPI_PCIE_REQ_SUPPORT) {
 467                 decode_osc_support(root, "not requesting OS control; OS requires",
 468                                    ACPI_PCIE_REQ_SUPPORT);
 469                 return;
 470         }
 471
 472         control = OSC_PCI_EXPRESS_CAPABILITY_CONTROL
 473                 | OSC_PCI_EXPRESS_PME_CONTROL;
 474
 475         if (IS_ENABLED(CONFIG_PCIEASPM))
 476                 control |= OSC_PCI_EXPRESS_LTR_CONTROL;
 477
 478         if (IS_ENABLED(CONFIG_HOTPLUG_PCI_PCIE))
 479                 control |= OSC_PCI_EXPRESS_NATIVE_HP_CONTROL;
 480
 481         if (IS_ENABLED(CONFIG_HOTPLUG_PCI_SHPC))
 482                 control |= OSC_PCI_SHPC_NATIVE_HP_CONTROL;
 483
 484         if (pci_aer_available())
 485                 control |= OSC_PCI_EXPRESS_AER_CONTROL;
 486
 487         /*
 488          * Per the Downstream Port Containment Related Enhancements ECN to
 489          * the PCI Firmware Spec, r3.2, sec 4.5.1, table 4-5,
 490          * OSC_PCI_EXPRESS_DPC_CONTROL indicates the OS supports both DPC
 491          * and EDR.
 492          */
 493         if (IS_ENABLED(CONFIG_PCIE_DPC) && IS_ENABLED(CONFIG_PCIE_EDR))
 494                 control |= OSC_PCI_EXPRESS_DPC_CONTROL;
 495
 496         requested = control;
 497         status = acpi_pci_osc_control_set(handle, &control,
 498                                           OSC_PCI_EXPRESS_CAPABILITY_CONTROL);
 499         if (ACPI_SUCCESS(status)) {
 500                 decode_osc_control(root, "OS now controls", control);
 501                 if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) {
 502                         /*
 503                          * We have ASPM control, but the FADT indicates that
 504                          * it's unsupported. Leave existing configuration
 505                          * intact and prevent the OS from touching it.
 506                          */
 507                         dev_info(&device->dev, "FADT indicates ASPM is unsupported, using BIOS configuration\n");
 508                         *no_aspm = 1;
 509                 }
 510         } else {
 511                 decode_osc_control(root, "OS requested", requested);
 512                 decode_osc_control(root, "platform willing to grant", control);
 513                 dev_info(&device->dev, "_OSC failed (%s); disabling ASPM\n",
 514                         acpi_format_exception(status));
 515
 516                 /*
 517                  * We want to disable ASPM here, but aspm_disabled
 518                  * needs to remain in its state from boot so that we
 519                  * properly handle PCIe 1.1 devices.  So we set this
 520                  * flag here, to defer the action until after the ACPI
 521                  * root scan.
 522                  */
 523                 *no_aspm = 1;
 524         }
 525 }
 526
 527 static int acpi_pci_root_add(struct acpi_device *device,
 528                              const struct acpi_device_id *not_used)
 529 {
 530         unsigned long long segment, bus;
 531         acpi_status status;
 532         int result;
 533         struct acpi_pci_root *root;
 534         acpi_handle handle = device->handle;
 535         int no_aspm = 0;
 536         bool hotadd = system_state == SYSTEM_RUNNING;
 537         bool is_pcie;
 538
 539         root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
 540         if (!root)
 541                 return -ENOMEM;
 542
 543         segment = 0;
 544         status = acpi_evaluate_integer(handle, METHOD_NAME__SEG, NULL,
 545                                        &segment);
 546         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 547                 dev_err(&device->dev,  "can't evaluate _SEG\n");
 548                 result = -ENODEV;
 549                 goto end;
 550         }
 551
 552         /* Check _CRS first, then _BBN.  If no _BBN, default to zero. */
 553         root->secondary.flags = IORESOURCE_BUS;
 554         status = try_get_root_bridge_busnr(handle, &root->secondary);
 555         if (ACPI_FAILURE(status)) {
 556                 /*
 557                  * We need both the start and end of the downstream bus range
 558                  * to interpret _CBA (MMCONFIG base address), so it really is
 559                  * supposed to be in _CRS.  If we don't find it there, all we
 560                  * can do is assume [_BBN-0xFF] or [0-0xFF].
 561                  */
 562                 root->secondary.end = 0xFF;
 563                 dev_warn(&device->dev,
 564                          FW_BUG "no secondary bus range in _CRS\n");
 565                 status = acpi_evaluate_integer(handle, METHOD_NAME__BBN,
 566                                                NULL, &bus);
 567                 if (ACPI_SUCCESS(status))
 568                         root->secondary.start = bus;
 569                 else if (status == AE_NOT_FOUND)
 570                         root->secondary.start = 0;
 571                 else {
 572                         dev_err(&device->dev, "can't evaluate _BBN\n");
 573                         result = -ENODEV;
 574                         goto end;
 575                 }
 576         }
 577
 578         root->device = device;
 579         root->segment = segment & 0xFFFF;
 580         strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
 581         strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
 582         device->driver_data = root;
 583
 584         if (hotadd && dmar_device_add(handle)) {
 585                 result = -ENXIO;
 586                 goto end;
 587         }
 588
 589         pr_info(PREFIX "%s [%s] (domain %04x %pR)\n",
 590                acpi_device_name(device), acpi_device_bid(device),
 591                root->segment, &root->secondary);
 592
 593         root->mcfg_addr = acpi_pci_root_get_mcfg_addr(handle);
 594
 595         is_pcie = strcmp(acpi_device_hid(device), "PNP0A08") == 0;
 596         negotiate_os_control(root, &no_aspm, is_pcie);
 597
 598         /*
 599          * TBD: Need PCI interface for enumeration/configuration of roots.
 600          */
 601
 602         /*
 603          * Scan the Root Bridge
 604          * --------------------
 605          * Must do this prior to any attempt to bind the root device, as the
 606          * PCI namespace does not get created until this call is made (and
 607          * thus the root bridge's pci_dev does not exist).
 608          */
 609         root->bus = pci_acpi_scan_root(root);
 610         if (!root->bus) {
 611                 dev_err(&device->dev,
 612                         "Bus %04x:%02x not present in PCI namespace\n",
 613                         root->segment, (unsigned int)root->secondary.start);
 614                 device->driver_data = NULL;
 615                 result = -ENODEV;
 616                 goto remove_dmar;
 617         }
 618
 619         if (no_aspm)
 620                 pcie_no_aspm();
 621
 622         pci_acpi_add_bus_pm_notifier(device);
 623         device_set_wakeup_capable(root->bus->bridge, device->wakeup.flags.valid);
 624
 625         if (hotadd) {
 626                 pcibios_resource_survey_bus(root->bus);
 627                 pci_assign_unassigned_root_bus_resources(root->bus);
 628                 /*
 629                  * This is only called for the hotadd case. For the boot-time
 630                  * case, we need to wait until after PCI initialization in
 631                  * order to deal with IOAPICs mapped in on a PCI BAR.
 632                  *
 633                  * This is currently x86-specific, because acpi_ioapic_add()
 634                  * is an empty function without CONFIG_ACPI_HOTPLUG_IOAPIC.
 635                  * And CONFIG_ACPI_HOTPLUG_IOAPIC depends on CONFIG_X86_IO_APIC
 636                  * (see drivers/acpi/Kconfig).
 637                  */
 638                 acpi_ioapic_add(root->device->handle);
 639         }
 640
 641         pci_lock_rescan_remove();
 642         pci_bus_add_devices(root->bus);
 643         pci_unlock_rescan_remove();
 644         return 1;
 645
 646 remove_dmar:
 647         if (hotadd)
 648                 dmar_device_remove(handle);
 649 end:
 650         kfree(root);
 651         return result;
 652 }
 653
 654 static void acpi_pci_root_remove(struct acpi_device *device)
 655 {
 656         struct acpi_pci_root *root = acpi_driver_data(device);
 657
 658         pci_lock_rescan_remove();
 659
 660         pci_stop_root_bus(root->bus);
 661
 662         pci_ioapic_remove(root);
 663         device_set_wakeup_capable(root->bus->bridge, false);
 664         pci_acpi_remove_bus_pm_notifier(device);
 665
 666         pci_remove_root_bus(root->bus);
 667         WARN_ON(acpi_ioapic_remove(root));
 668
 669         dmar_device_remove(device->handle);
 670
 671         pci_unlock_rescan_remove();
 672
 673         kfree(root);
 674 }
 675
 676 /*
 677  * Following code to support acpi_pci_root_create() is copied from
 678  * arch/x86/pci/acpi.c and modified so it could be reused by x86, IA64
 679  * and ARM64.
 680  */
 681 static void acpi_pci_root_validate_resources(struct device *dev,
 682                                              struct list_head *resources,
 683                                              unsigned long type)
 684 {
 685         LIST_HEAD(list);
 686         struct resource *res1, *res2, *root = NULL;
 687         struct resource_entry *tmp, *entry, *entry2;
 688
 689         BUG_ON((type & (IORESOURCE_MEM | IORESOURCE_IO)) == 0);
 690         root = (type & IORESOURCE_MEM) ? &iomem_resource : &ioport_resource;
 691
 692         list_splice_init(resources, &list);
 693         resource_list_for_each_entry_safe(entry, tmp, &list) {
 694                 bool free = false;
 695                 resource_size_t end;
 696
 697                 res1 = entry->res;
 698                 if (!(res1->flags & type))
 699                         goto next;
 700
 701                 /* Exclude non-addressable range or non-addressable portion */
 702                 end = min(res1->end, root->end);
 703                 if (end <= res1->start) {
 704                         dev_info(dev, "host bridge window %pR (ignored, not CPU addressable)\n",
 705                                  res1);
 706                         free = true;
 707                         goto next;
 708                 } else if (res1->end != end) {
 709                         dev_info(dev, "host bridge window %pR ([%#llx-%#llx] ignored, not CPU addressable)\n",
 710                                  res1, (unsigned long long)end + 1,
 711                                  (unsigned long long)res1->end);
 712                         res1->end = end;
 713                 }
 714
 715                 resource_list_for_each_entry(entry2, resources) {
 716                         res2 = entry2->res;
 717                         if (!(res2->flags & type))
 718                                 continue;
 719
 720                         /*
 721                          * I don't like throwing away windows because then
 722                          * our resources no longer match the ACPI _CRS, but
 723                          * the kernel resource tree doesn't allow overlaps.
 724                          */
 725                         if (resource_union(res1, res2, res2)) {
 726                                 dev_info(dev, "host bridge window expanded to %pR; %pR ignored\n",
 727                                          res2, res1);
 728                                 free = true;
 729                                 goto next;
 730                         }
 731                 }
 732
 733 next:
 734                 resource_list_del(entry);
 735                 if (free)
 736                         resource_list_free_entry(entry);
 737                 else
 738                         resource_list_add_tail(entry, resources);
 739         }
 740 }
 741
 742 static void acpi_pci_root_remap_iospace(struct fwnode_handle *fwnode,
 743                         struct resource_entry *entry)
 744 {
 745 #ifdef PCI_IOBASE
 746         struct resource *res = entry->res;
 747         resource_size_t cpu_addr = res->start;
 748         resource_size_t pci_addr = cpu_addr - entry->offset;
 749         resource_size_t length = resource_size(res);
 750         unsigned long port;
 751
 752         if (pci_register_io_range(fwnode, cpu_addr, length))
 753                 goto err;
 754
 755         port = pci_address_to_pio(cpu_addr);
 756         if (port == (unsigned long)-1)
 757                 goto err;
 758
 759         res->start = port;
 760         res->end = port + length - 1;
 761         entry->offset = port - pci_addr;
 762
 763         if (pci_remap_iospace(res, cpu_addr) < 0)
 764                 goto err;
 765
 766         pr_info("Remapped I/O %pa to %pR\n", &cpu_addr, res);
 767         return;
 768 err:
 769         res->flags |= IORESOURCE_DISABLED;
 770 #endif
 771 }
 772
 773 int acpi_pci_probe_root_resources(struct acpi_pci_root_info *info)
 774 {
 775         int ret;
 776         struct list_head *list = &info->resources;
 777         struct acpi_device *device = info->bridge;
 778         struct resource_entry *entry, *tmp;
 779         unsigned long flags;
 780
 781         flags = IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_MEM_8AND16BIT;
 782         ret = acpi_dev_get_resources(device, list,
 783                                      acpi_dev_filter_resource_type_cb,
 784                                      (void *)flags);
 785         if (ret < 0)
 786                 dev_warn(&device->dev,
 787                          "failed to parse _CRS method, error code %d\n", ret);
 788         else if (ret == 0)
 789                 dev_dbg(&device->dev,
 790                         "no IO and memory resources present in _CRS\n");
 791         else {
 792                 resource_list_for_each_entry_safe(entry, tmp, list) {
 793                         if (entry->res->flags & IORESOURCE_IO)
 794                                 acpi_pci_root_remap_iospace(&device->fwnode,
 795                                                 entry);
 796
 797                         if (entry->res->flags & IORESOURCE_DISABLED)
 798                                 resource_list_destroy_entry(entry);
 799                         else
 800                                 entry->res->name = info->name;
 801                 }
 802                 acpi_pci_root_validate_resources(&device->dev, list,
 803                                                  IORESOURCE_MEM);
 804                 acpi_pci_root_validate_resources(&device->dev, list,
 805                                                  IORESOURCE_IO);
 806         }
 807
 808         return ret;
 809 }
 810
 811 static void pci_acpi_root_add_resources(struct acpi_pci_root_info *info)
 812 {
 813         struct resource_entry *entry, *tmp;
 814         struct resource *res, *conflict, *root = NULL;
 815
 816         resource_list_for_each_entry_safe(entry, tmp, &info->resources) {
 817                 res = entry->res;
 818                 if (res->flags & IORESOURCE_MEM)
 819                         root = &iomem_resource;
 820                 else if (res->flags & IORESOURCE_IO)
 821                         root = &ioport_resource;
 822                 else
 823                         continue;
 824
 825                 /*
 826                  * Some legacy x86 host bridge drivers use iomem_resource and
 827                  * ioport_resource as default resource pool, skip it.
 828                  */
 829                 if (res == root)
 830                         continue;
 831
 832                 conflict = insert_resource_conflict(root, res);
 833                 if (conflict) {
 834                         dev_info(&info->bridge->dev,
 835                                  "ignoring host bridge window %pR (conflicts with %s %pR)\n",
 836                                  res, conflict->name, conflict);
 837                         resource_list_destroy_entry(entry);
 838                 }
 839         }
 840 }
 841
 842 static void __acpi_pci_root_release_info(struct acpi_pci_root_info *info)
 843 {
 844         struct resource *res;
 845         struct resource_entry *entry, *tmp;
 846
 847         if (!info)
 848                 return;
 849
 850         resource_list_for_each_entry_safe(entry, tmp, &info->resources) {
 851                 res = entry->res;
 852                 if (res->parent &&
 853                     (res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
 854                         release_resource(res);
 855                 resource_list_destroy_entry(entry);
 856         }
 857
 858         info->ops->release_info(info);
 859 }
 860
 861 static void acpi_pci_root_release_info(struct pci_host_bridge *bridge)
 862 {
 863         struct resource *res;
 864         struct resource_entry *entry;
 865
 866         resource_list_for_each_entry(entry, &bridge->windows) {
 867                 res = entry->res;
 868                 if (res->flags & IORESOURCE_IO)
 869                         pci_unmap_iospace(res);
 870                 if (res->parent &&
 871                     (res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
 872                         release_resource(res);
 873         }
 874         __acpi_pci_root_release_info(bridge->release_data);
 875 }
 876
 877 struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root,
 878                                      struct acpi_pci_root_ops *ops,
 879                                      struct acpi_pci_root_info *info,
 880                                      void *sysdata)
 881 {
 882         int ret, busnum = root->secondary.start;
 883         struct acpi_device *device = root->device;
 884         int node = acpi_get_node(device->handle);
 885         struct pci_bus *bus;
 886         struct pci_host_bridge *host_bridge;
 887         union acpi_object *obj;
 888
 889         info->root = root;
 890         info->bridge = device;
 891         info->ops = ops;
 892         INIT_LIST_HEAD(&info->resources);
 893         snprintf(info->name, sizeof(info->name), "PCI Bus %04x:%02x",
 894                  root->segment, busnum);
 895
 896         if (ops->init_info && ops->init_info(info))
 897                 goto out_release_info;
 898         if (ops->prepare_resources)
 899                 ret = ops->prepare_resources(info);
 900         else
 901                 ret = acpi_pci_probe_root_resources(info);
 902         if (ret < 0)
 903                 goto out_release_info;
 904
 905         pci_acpi_root_add_resources(info);
 906         pci_add_resource(&info->resources, &root->secondary);
 907         bus = pci_create_root_bus(NULL, busnum, ops->pci_ops,
 908                                   sysdata, &info->resources);
 909         if (!bus)
 910                 goto out_release_info;
 911
 912         host_bridge = to_pci_host_bridge(bus->bridge);
 913         if (!(root->osc_control_set & OSC_PCI_EXPRESS_NATIVE_HP_CONTROL))
 914                 host_bridge->native_pcie_hotplug = 0;
 915         if (!(root->osc_control_set & OSC_PCI_SHPC_NATIVE_HP_CONTROL))
 916                 host_bridge->native_shpc_hotplug = 0;
 917         if (!(root->osc_control_set & OSC_PCI_EXPRESS_AER_CONTROL))
 918                 host_bridge->native_aer = 0;
 919         if (!(root->osc_control_set & OSC_PCI_EXPRESS_PME_CONTROL))
 920                 host_bridge->native_pme = 0;
 921         if (!(root->osc_control_set & OSC_PCI_EXPRESS_LTR_CONTROL))
 922                 host_bridge->native_ltr = 0;
 923         if (!(root->osc_control_set & OSC_PCI_EXPRESS_DPC_CONTROL))
 924                 host_bridge->native_dpc = 0;
 925
 926         /*
 927          * Evaluate the "PCI Boot Configuration" _DSM Function.  If it
 928          * exists and returns 0, we must preserve any PCI resource
 929          * assignments made by firmware for this host bridge.
 930          */
 931         obj = acpi_evaluate_dsm(ACPI_HANDLE(bus->bridge), &pci_acpi_dsm_guid, 1,
 932                                 DSM_PCI_PRESERVE_BOOT_CONFIG, NULL);
 933         if (obj && obj->type == ACPI_TYPE_INTEGER && obj->integer.value == 0)
 934                 host_bridge->preserve_config = 1;
 935         ACPI_FREE(obj);
 936
 937         pci_scan_child_bus(bus);
 938         pci_set_host_bridge_release(host_bridge, acpi_pci_root_release_info,
 939                                     info);
 940         if (node != NUMA_NO_NODE)
 941                 dev_printk(KERN_DEBUG, &bus->dev, "on NUMA node %d\n", node);
 942         return bus;
 943
 944 out_release_info:
 945         __acpi_pci_root_release_info(info);
 946         return NULL;
 947 }
 948
 949 void __init acpi_pci_root_init(void)
 950 {
 951         acpi_hest_init();
 952         if (acpi_pci_disabled)
 953                 return;
 954
 955         pci_acpi_crs_quirks();
 956         acpi_scan_add_handler_with_hotplug(&pci_root_handler, "pci_root");
 957 }