Pileus Git - ~andy/linux/blob - drivers/acpi/pci_root.c

   1 /*
   2  *  pci_root.c - ACPI PCI Root Bridge Driver ($Revision: 40 $)
   3  *
   4  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
   5  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
   6  *
   7  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   8  *
   9  *  This program is free software; you can redistribute it and/or modify
  10  *  it under the terms of the GNU General Public License as published by
  11  *  the Free Software Foundation; either version 2 of the License, or (at
  12  *  your option) any later version.
  13  *
  14  *  This program is distributed in the hope that it will be useful, but
  15  *  WITHOUT ANY WARRANTY; without even the implied warranty of
  16  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  *  General Public License for more details.
  18  *
  19  *  You should have received a copy of the GNU General Public License along
  20  *  with this program; if not, write to the Free Software Foundation, Inc.,
  21  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  22  *
  23  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  24  */
  25
  26 #include <linux/kernel.h>
  27 #include <linux/module.h>
  28 #include <linux/init.h>
  29 #include <linux/types.h>
  30 #include <linux/mutex.h>
  31 #include <linux/pm.h>
  32 #include <linux/pm_runtime.h>
  33 #include <linux/pci.h>
  34 #include <linux/pci-acpi.h>
  35 #include <linux/pci-aspm.h>
  36 #include <linux/acpi.h>
  37 #include <linux/slab.h>
  38 #include <acpi/acpi_bus.h>
  39 #include <acpi/acpi_drivers.h>
  40 #include <acpi/apei.h>
  41
  42 #define PREFIX "ACPI: "
  43
  44 #define _COMPONENT              ACPI_PCI_COMPONENT
  45 ACPI_MODULE_NAME("pci_root");
  46 #define ACPI_PCI_ROOT_CLASS             "pci_bridge"
  47 #define ACPI_PCI_ROOT_DEVICE_NAME       "PCI Root Bridge"
  48 static int acpi_pci_root_add(struct acpi_device *device);
  49 static int acpi_pci_root_remove(struct acpi_device *device, int type);
  50
  51 #define ACPI_PCIE_REQ_SUPPORT (OSC_EXT_PCI_CONFIG_SUPPORT \
  52                                 | OSC_ACTIVE_STATE_PWR_SUPPORT \
  53                                 | OSC_CLOCK_PWR_CAPABILITY_SUPPORT \
  54                                 | OSC_MSI_SUPPORT)
  55
  56 static const struct acpi_device_id root_device_ids[] = {
  57         {"PNP0A03", 0},
  58         {"", 0},
  59 };
  60 MODULE_DEVICE_TABLE(acpi, root_device_ids);
  61
  62 static struct acpi_driver acpi_pci_root_driver = {
  63         .name = "pci_root",
  64         .class = ACPI_PCI_ROOT_CLASS,
  65         .ids = root_device_ids,
  66         .ops = {
  67                 .add = acpi_pci_root_add,
  68                 .remove = acpi_pci_root_remove,
  69                 },
  70 };
  71
  72 /* Lock to protect both acpi_pci_roots and acpi_pci_drivers lists */
  73 static DEFINE_MUTEX(acpi_pci_root_lock);
  74 static LIST_HEAD(acpi_pci_roots);
  75 static LIST_HEAD(acpi_pci_drivers);
  76
  77 static DEFINE_MUTEX(osc_lock);
  78
  79 int acpi_pci_register_driver(struct acpi_pci_driver *driver)
  80 {
  81         int n = 0;
  82         struct acpi_pci_root *root;
  83
  84         mutex_lock(&acpi_pci_root_lock);
  85         list_add_tail(&driver->node, &acpi_pci_drivers);
  86         if (driver->add)
  87                 list_for_each_entry(root, &acpi_pci_roots, node) {
  88                         driver->add(root);
  89                         n++;
  90                 }
  91         mutex_unlock(&acpi_pci_root_lock);
  92
  93         return n;
  94 }
  95 EXPORT_SYMBOL(acpi_pci_register_driver);
  96
  97 void acpi_pci_unregister_driver(struct acpi_pci_driver *driver)
  98 {
  99         struct acpi_pci_root *root;
 100
 101         mutex_lock(&acpi_pci_root_lock);
 102         list_del(&driver->node);
 103         if (driver->remove)
 104                 list_for_each_entry(root, &acpi_pci_roots, node)
 105                         driver->remove(root);
 106         mutex_unlock(&acpi_pci_root_lock);
 107 }
 108 EXPORT_SYMBOL(acpi_pci_unregister_driver);
 109
 110 /**
 111  * acpi_is_root_bridge - determine whether an ACPI CA node is a PCI root bridge
 112  * @handle - the ACPI CA node in question.
 113  *
 114  * Note: we could make this API take a struct acpi_device * instead, but
 115  * for now, it's more convenient to operate on an acpi_handle.
 116  */
 117 int acpi_is_root_bridge(acpi_handle handle)
 118 {
 119         int ret;
 120         struct acpi_device *device;
 121
 122         ret = acpi_bus_get_device(handle, &device);
 123         if (ret)
 124                 return 0;
 125
 126         ret = acpi_match_device_ids(device, root_device_ids);
 127         if (ret)
 128                 return 0;
 129         else
 130                 return 1;
 131 }
 132 EXPORT_SYMBOL_GPL(acpi_is_root_bridge);
 133
 134 static acpi_status
 135 get_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
 136 {
 137         struct resource *res = data;
 138         struct acpi_resource_address64 address;
 139
 140         if (resource->type != ACPI_RESOURCE_TYPE_ADDRESS16 &&
 141             resource->type != ACPI_RESOURCE_TYPE_ADDRESS32 &&
 142             resource->type != ACPI_RESOURCE_TYPE_ADDRESS64)
 143                 return AE_OK;
 144
 145         acpi_resource_to_address64(resource, &address);
 146         if ((address.address_length > 0) &&
 147             (address.resource_type == ACPI_BUS_NUMBER_RANGE)) {
 148                 res->start = address.minimum;
 149                 res->end = address.minimum + address.address_length - 1;
 150         }
 151
 152         return AE_OK;
 153 }
 154
 155 static acpi_status try_get_root_bridge_busnr(acpi_handle handle,
 156                                              struct resource *res)
 157 {
 158         acpi_status status;
 159
 160         res->start = -1;
 161         status =
 162             acpi_walk_resources(handle, METHOD_NAME__CRS,
 163                                 get_root_bridge_busnr_callback, res);
 164         if (ACPI_FAILURE(status))
 165                 return status;
 166         if (res->start == -1)
 167                 return AE_ERROR;
 168         return AE_OK;
 169 }
 170
 171 static u8 pci_osc_uuid_str[] = "33DB4D5B-1FF7-401C-9657-7441C03DD766";
 172
 173 static acpi_status acpi_pci_run_osc(acpi_handle handle,
 174                                     const u32 *capbuf, u32 *retval)
 175 {
 176         struct acpi_osc_context context = {
 177                 .uuid_str = pci_osc_uuid_str,
 178                 .rev = 1,
 179                 .cap.length = 12,
 180                 .cap.pointer = (void *)capbuf,
 181         };
 182         acpi_status status;
 183
 184         status = acpi_run_osc(handle, &context);
 185         if (ACPI_SUCCESS(status)) {
 186                 *retval = *((u32 *)(context.ret.pointer + 8));
 187                 kfree(context.ret.pointer);
 188         }
 189         return status;
 190 }
 191
 192 static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root,
 193                                         u32 support,
 194                                         u32 *control)
 195 {
 196         acpi_status status;
 197         u32 result, capbuf[3];
 198
 199         support &= OSC_PCI_SUPPORT_MASKS;
 200         support |= root->osc_support_set;
 201
 202         capbuf[OSC_QUERY_TYPE] = OSC_QUERY_ENABLE;
 203         capbuf[OSC_SUPPORT_TYPE] = support;
 204         if (control) {
 205                 *control &= OSC_PCI_CONTROL_MASKS;
 206                 capbuf[OSC_CONTROL_TYPE] = *control | root->osc_control_set;
 207         } else {
 208                 /* Run _OSC query for all possible controls. */
 209                 capbuf[OSC_CONTROL_TYPE] = OSC_PCI_CONTROL_MASKS;
 210         }
 211
 212         status = acpi_pci_run_osc(root->device->handle, capbuf, &result);
 213         if (ACPI_SUCCESS(status)) {
 214                 root->osc_support_set = support;
 215                 if (control)
 216                         *control = result;
 217         }
 218         return status;
 219 }
 220
 221 static acpi_status acpi_pci_osc_support(struct acpi_pci_root *root, u32 flags)
 222 {
 223         acpi_status status;
 224         acpi_handle tmp;
 225
 226         status = acpi_get_handle(root->device->handle, "_OSC", &tmp);
 227         if (ACPI_FAILURE(status))
 228                 return status;
 229         mutex_lock(&osc_lock);
 230         status = acpi_pci_query_osc(root, flags, NULL);
 231         mutex_unlock(&osc_lock);
 232         return status;
 233 }
 234
 235 struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle)
 236 {
 237         struct acpi_pci_root *root;
 238         struct acpi_device *device;
 239
 240         if (acpi_bus_get_device(handle, &device) ||
 241             acpi_match_device_ids(device, root_device_ids))
 242                 return NULL;
 243
 244         root = acpi_driver_data(device);
 245
 246         return root;
 247 }
 248 EXPORT_SYMBOL_GPL(acpi_pci_find_root);
 249
 250 struct acpi_handle_node {
 251         struct list_head node;
 252         acpi_handle handle;
 253 };
 254
 255 /**
 256  * acpi_get_pci_dev - convert ACPI CA handle to struct pci_dev
 257  * @handle: the handle in question
 258  *
 259  * Given an ACPI CA handle, the desired PCI device is located in the
 260  * list of PCI devices.
 261  *
 262  * If the device is found, its reference count is increased and this
 263  * function returns a pointer to its data structure.  The caller must
 264  * decrement the reference count by calling pci_dev_put().
 265  * If no device is found, %NULL is returned.
 266  */
 267 struct pci_dev *acpi_get_pci_dev(acpi_handle handle)
 268 {
 269         int dev, fn;
 270         unsigned long long adr;
 271         acpi_status status;
 272         acpi_handle phandle;
 273         struct pci_bus *pbus;
 274         struct pci_dev *pdev = NULL;
 275         struct acpi_handle_node *node, *tmp;
 276         struct acpi_pci_root *root;
 277         LIST_HEAD(device_list);
 278
 279         /*
 280          * Walk up the ACPI CA namespace until we reach a PCI root bridge.
 281          */
 282         phandle = handle;
 283         while (!acpi_is_root_bridge(phandle)) {
 284                 node = kzalloc(sizeof(struct acpi_handle_node), GFP_KERNEL);
 285                 if (!node)
 286                         goto out;
 287
 288                 INIT_LIST_HEAD(&node->node);
 289                 node->handle = phandle;
 290                 list_add(&node->node, &device_list);
 291
 292                 status = acpi_get_parent(phandle, &phandle);
 293                 if (ACPI_FAILURE(status))
 294                         goto out;
 295         }
 296
 297         root = acpi_pci_find_root(phandle);
 298         if (!root)
 299                 goto out;
 300
 301         pbus = root->bus;
 302
 303         /*
 304          * Now, walk back down the PCI device tree until we return to our
 305          * original handle. Assumes that everything between the PCI root
 306          * bridge and the device we're looking for must be a P2P bridge.
 307          */
 308         list_for_each_entry(node, &device_list, node) {
 309                 acpi_handle hnd = node->handle;
 310                 status = acpi_evaluate_integer(hnd, "_ADR", NULL, &adr);
 311                 if (ACPI_FAILURE(status))
 312                         goto out;
 313                 dev = (adr >> 16) & 0xffff;
 314                 fn  = adr & 0xffff;
 315
 316                 pdev = pci_get_slot(pbus, PCI_DEVFN(dev, fn));
 317                 if (!pdev || hnd == handle)
 318                         break;
 319
 320                 pbus = pdev->subordinate;
 321                 pci_dev_put(pdev);
 322
 323                 /*
 324                  * This function may be called for a non-PCI device that has a
 325                  * PCI parent (eg. a disk under a PCI SATA controller).  In that
 326                  * case pdev->subordinate will be NULL for the parent.
 327                  */
 328                 if (!pbus) {
 329                         dev_dbg(&pdev->dev, "Not a PCI-to-PCI bridge\n");
 330                         pdev = NULL;
 331                         break;
 332                 }
 333         }
 334 out:
 335         list_for_each_entry_safe(node, tmp, &device_list, node)
 336                 kfree(node);
 337
 338         return pdev;
 339 }
 340 EXPORT_SYMBOL_GPL(acpi_get_pci_dev);
 341
 342 /**
 343  * acpi_pci_osc_control_set - Request control of PCI root _OSC features.
 344  * @handle: ACPI handle of a PCI root bridge (or PCIe Root Complex).
 345  * @mask: Mask of _OSC bits to request control of, place to store control mask.
 346  * @req: Mask of _OSC bits the control of is essential to the caller.
 347  *
 348  * Run _OSC query for @mask and if that is successful, compare the returned
 349  * mask of control bits with @req.  If all of the @req bits are set in the
 350  * returned mask, run _OSC request for it.
 351  *
 352  * The variable at the @mask address may be modified regardless of whether or
 353  * not the function returns success.  On success it will contain the mask of
 354  * _OSC bits the BIOS has granted control of, but its contents are meaningless
 355  * on failure.
 356  **/
 357 acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 *mask, u32 req)
 358 {
 359         struct acpi_pci_root *root;
 360         acpi_status status;
 361         u32 ctrl, capbuf[3];
 362         acpi_handle tmp;
 363
 364         if (!mask)
 365                 return AE_BAD_PARAMETER;
 366
 367         ctrl = *mask & OSC_PCI_CONTROL_MASKS;
 368         if ((ctrl & req) != req)
 369                 return AE_TYPE;
 370
 371         root = acpi_pci_find_root(handle);
 372         if (!root)
 373                 return AE_NOT_EXIST;
 374
 375         status = acpi_get_handle(handle, "_OSC", &tmp);
 376         if (ACPI_FAILURE(status))
 377                 return status;
 378
 379         mutex_lock(&osc_lock);
 380
 381         *mask = ctrl | root->osc_control_set;
 382         /* No need to evaluate _OSC if the control was already granted. */
 383         if ((root->osc_control_set & ctrl) == ctrl)
 384                 goto out;
 385
 386         /* Need to check the available controls bits before requesting them. */
 387         while (*mask) {
 388                 status = acpi_pci_query_osc(root, root->osc_support_set, mask);
 389                 if (ACPI_FAILURE(status))
 390                         goto out;
 391                 if (ctrl == *mask)
 392                         break;
 393                 ctrl = *mask;
 394         }
 395
 396         if ((ctrl & req) != req) {
 397                 status = AE_SUPPORT;
 398                 goto out;
 399         }
 400
 401         capbuf[OSC_QUERY_TYPE] = 0;
 402         capbuf[OSC_SUPPORT_TYPE] = root->osc_support_set;
 403         capbuf[OSC_CONTROL_TYPE] = ctrl;
 404         status = acpi_pci_run_osc(handle, capbuf, mask);
 405         if (ACPI_SUCCESS(status))
 406                 root->osc_control_set = *mask;
 407 out:
 408         mutex_unlock(&osc_lock);
 409         return status;
 410 }
 411 EXPORT_SYMBOL(acpi_pci_osc_control_set);
 412
 413 static int acpi_pci_root_add(struct acpi_device *device)
 414 {
 415         unsigned long long segment, bus;
 416         acpi_status status;
 417         int result;
 418         struct acpi_pci_root *root;
 419         struct acpi_pci_driver *driver;
 420         u32 flags, base_flags;
 421         bool is_osc_granted = false;
 422
 423         root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
 424         if (!root)
 425                 return -ENOMEM;
 426
 427         segment = 0;
 428         status = acpi_evaluate_integer(device->handle, METHOD_NAME__SEG, NULL,
 429                                        &segment);
 430         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 431                 printk(KERN_ERR PREFIX "can't evaluate _SEG\n");
 432                 result = -ENODEV;
 433                 goto end;
 434         }
 435
 436         /* Check _CRS first, then _BBN.  If no _BBN, default to zero. */
 437         root->secondary.flags = IORESOURCE_BUS;
 438         status = try_get_root_bridge_busnr(device->handle, &root->secondary);
 439         if (ACPI_FAILURE(status)) {
 440                 /*
 441                  * We need both the start and end of the downstream bus range
 442                  * to interpret _CBA (MMCONFIG base address), so it really is
 443                  * supposed to be in _CRS.  If we don't find it there, all we
 444                  * can do is assume [_BBN-0xFF] or [0-0xFF].
 445                  */
 446                 root->secondary.end = 0xFF;
 447                 printk(KERN_WARNING FW_BUG PREFIX
 448                        "no secondary bus range in _CRS\n");
 449                 status = acpi_evaluate_integer(device->handle, METHOD_NAME__BBN,
 450                                                NULL, &bus);
 451                 if (ACPI_SUCCESS(status))
 452                         root->secondary.start = bus;
 453                 else if (status == AE_NOT_FOUND)
 454                         root->secondary.start = 0;
 455                 else {
 456                         printk(KERN_ERR PREFIX "can't evaluate _BBN\n");
 457                         result = -ENODEV;
 458                         goto end;
 459                 }
 460         }
 461
 462         INIT_LIST_HEAD(&root->node);
 463         root->device = device;
 464         root->segment = segment & 0xFFFF;
 465         strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
 466         strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
 467         device->driver_data = root;
 468
 469         printk(KERN_INFO PREFIX "%s [%s] (domain %04x %pR)\n",
 470                acpi_device_name(device), acpi_device_bid(device),
 471                root->segment, &root->secondary);
 472
 473         root->mcfg_addr = acpi_pci_root_get_mcfg_addr(device->handle);
 474
 475         /*
 476          * All supported architectures that use ACPI have support for
 477          * PCI domains, so we indicate this in _OSC support capabilities.
 478          */
 479         flags = base_flags = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
 480         acpi_pci_osc_support(root, flags);
 481
 482         /* Indicate support for various _OSC capabilities. */
 483         if (pci_ext_cfg_avail())
 484                 flags |= OSC_EXT_PCI_CONFIG_SUPPORT;
 485         if (pcie_aspm_support_enabled()) {
 486                 flags |= OSC_ACTIVE_STATE_PWR_SUPPORT |
 487                 OSC_CLOCK_PWR_CAPABILITY_SUPPORT;
 488         }
 489         if (pci_msi_enabled())
 490                 flags |= OSC_MSI_SUPPORT;
 491         if (flags != base_flags) {
 492                 status = acpi_pci_osc_support(root, flags);
 493                 if (ACPI_FAILURE(status)) {
 494                         dev_info(&device->dev, "ACPI _OSC support "
 495                                 "notification failed, disabling PCIe ASPM\n");
 496                         pcie_no_aspm();
 497                         flags = base_flags;
 498                 }
 499         }
 500         if (!pcie_ports_disabled
 501             && (flags & ACPI_PCIE_REQ_SUPPORT) == ACPI_PCIE_REQ_SUPPORT) {
 502                 flags = OSC_PCI_EXPRESS_CAP_STRUCTURE_CONTROL
 503                         | OSC_PCI_EXPRESS_NATIVE_HP_CONTROL
 504                         | OSC_PCI_EXPRESS_PME_CONTROL;
 505
 506                 if (pci_aer_available()) {
 507                         if (aer_acpi_firmware_first())
 508                                 dev_dbg(&device->dev,
 509                                         "PCIe errors handled by BIOS.\n");
 510                         else
 511                                 flags |= OSC_PCI_EXPRESS_AER_CONTROL;
 512                 }
 513
 514                 dev_info(&device->dev,
 515                         "Requesting ACPI _OSC control (0x%02x)\n", flags);
 516
 517                 status = acpi_pci_osc_control_set(device->handle, &flags,
 518                                        OSC_PCI_EXPRESS_CAP_STRUCTURE_CONTROL);
 519                 if (ACPI_SUCCESS(status)) {
 520                         is_osc_granted = true;
 521                         dev_info(&device->dev,
 522                                 "ACPI _OSC control (0x%02x) granted\n", flags);
 523                 } else {
 524                         is_osc_granted = false;
 525                         dev_info(&device->dev,
 526                                 "ACPI _OSC request failed (%s), "
 527                                 "returned control mask: 0x%02x\n",
 528                                 acpi_format_exception(status), flags);
 529                 }
 530         } else {
 531                 dev_info(&device->dev,
 532                         "Unable to request _OSC control "
 533                         "(_OSC support mask: 0x%02x)\n", flags);
 534         }
 535
 536         /*
 537          * TBD: Need PCI interface for enumeration/configuration of roots.
 538          */
 539
 540         mutex_lock(&acpi_pci_root_lock);
 541         list_add_tail(&root->node, &acpi_pci_roots);
 542         mutex_unlock(&acpi_pci_root_lock);
 543
 544         /*
 545          * Scan the Root Bridge
 546          * --------------------
 547          * Must do this prior to any attempt to bind the root device, as the
 548          * PCI namespace does not get created until this call is made (and
 549          * thus the root bridge's pci_dev does not exist).
 550          */
 551         root->bus = pci_acpi_scan_root(root);
 552         if (!root->bus) {
 553                 printk(KERN_ERR PREFIX
 554                             "Bus %04x:%02x not present in PCI namespace\n",
 555                             root->segment, (unsigned int)root->secondary.start);
 556                 result = -ENODEV;
 557                 goto out_del_root;
 558         }
 559
 560         /* ASPM setting */
 561         if (is_osc_granted) {
 562                 if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM)
 563                         pcie_clear_aspm(root->bus);
 564         } else {
 565                 pr_info("ACPI _OSC control for PCIe not granted, "
 566                         "disabling ASPM\n");
 567                 pcie_no_aspm();
 568         }
 569
 570         pci_acpi_add_bus_pm_notifier(device, root->bus);
 571         if (device->wakeup.flags.run_wake)
 572                 device_set_run_wake(root->bus->bridge, true);
 573
 574         if (system_state != SYSTEM_BOOTING) {
 575                 pcibios_resource_survey_bus(root->bus);
 576                 pci_assign_unassigned_bus_resources(root->bus);
 577         }
 578
 579         mutex_lock(&acpi_pci_root_lock);
 580         list_for_each_entry(driver, &acpi_pci_drivers, node)
 581                 if (driver->add)
 582                         driver->add(root);
 583         mutex_unlock(&acpi_pci_root_lock);
 584
 585         /* need to after hot-added ioapic is registered */
 586         if (system_state != SYSTEM_BOOTING)
 587                 pci_enable_bridges(root->bus);
 588
 589         pci_bus_add_devices(root->bus);
 590         return 0;
 591
 592 out_del_root:
 593         mutex_lock(&acpi_pci_root_lock);
 594         list_del(&root->node);
 595         mutex_unlock(&acpi_pci_root_lock);
 596
 597 end:
 598         kfree(root);
 599         return result;
 600 }
 601
 602 static int acpi_pci_root_remove(struct acpi_device *device, int type)
 603 {
 604         struct acpi_pci_root *root = acpi_driver_data(device);
 605         struct acpi_pci_driver *driver;
 606
 607         pci_stop_root_bus(root->bus);
 608
 609         mutex_lock(&acpi_pci_root_lock);
 610         list_for_each_entry_reverse(driver, &acpi_pci_drivers, node)
 611                 if (driver->remove)
 612                         driver->remove(root);
 613         mutex_unlock(&acpi_pci_root_lock);
 614
 615         device_set_run_wake(root->bus->bridge, false);
 616         pci_acpi_remove_bus_pm_notifier(device);
 617
 618         pci_remove_root_bus(root->bus);
 619
 620         mutex_lock(&acpi_pci_root_lock);
 621         list_del(&root->node);
 622         mutex_unlock(&acpi_pci_root_lock);
 623         kfree(root);
 624         return 0;
 625 }
 626
 627 int __init acpi_pci_root_init(void)
 628 {
 629         acpi_hest_init();
 630
 631         if (acpi_pci_disabled)
 632                 return 0;
 633
 634         pci_acpi_crs_quirks();
 635         if (acpi_bus_register_driver(&acpi_pci_root_driver) < 0)
 636                 return -ENODEV;
 637
 638         return 0;
 639 }
 640 /* Support root bridge hotplug */
 641
 642 static void handle_root_bridge_insertion(acpi_handle handle)
 643 {
 644         struct acpi_device *device;
 645
 646         if (!acpi_bus_get_device(handle, &device)) {
 647                 printk(KERN_DEBUG "acpi device exists...\n");
 648                 return;
 649         }
 650
 651         if (acpi_bus_scan(handle))
 652                 printk(KERN_ERR "cannot add bridge to acpi list\n");
 653 }
 654
 655 static void handle_root_bridge_removal(struct acpi_device *device)
 656 {
 657         struct acpi_eject_event *ej_event;
 658
 659         ej_event = kmalloc(sizeof(*ej_event), GFP_KERNEL);
 660         if (!ej_event) {
 661                 /* Inform firmware the hot-remove operation has error */
 662                 (void) acpi_evaluate_hotplug_ost(device->handle,
 663                                         ACPI_NOTIFY_EJECT_REQUEST,
 664                                         ACPI_OST_SC_NON_SPECIFIC_FAILURE,
 665                                         NULL);
 666                 return;
 667         }
 668
 669         ej_event->device = device;
 670         ej_event->event = ACPI_NOTIFY_EJECT_REQUEST;
 671
 672         acpi_bus_hot_remove_device(ej_event);
 673 }
 674
 675 static void _handle_hotplug_event_root(struct work_struct *work)
 676 {
 677         struct acpi_pci_root *root;
 678         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER };
 679         struct acpi_hp_work *hp_work;
 680         acpi_handle handle;
 681         u32 type;
 682
 683         hp_work = container_of(work, struct acpi_hp_work, work);
 684         handle = hp_work->handle;
 685         type = hp_work->type;
 686
 687         root = acpi_pci_find_root(handle);
 688
 689         acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
 690
 691         switch (type) {
 692         case ACPI_NOTIFY_BUS_CHECK:
 693                 /* bus enumerate */
 694                 printk(KERN_DEBUG "%s: Bus check notify on %s\n", __func__,
 695                                  (char *)buffer.pointer);
 696                 if (!root)
 697                         handle_root_bridge_insertion(handle);
 698
 699                 break;
 700
 701         case ACPI_NOTIFY_DEVICE_CHECK:
 702                 /* device check */
 703                 printk(KERN_DEBUG "%s: Device check notify on %s\n", __func__,
 704                                  (char *)buffer.pointer);
 705                 if (!root)
 706                         handle_root_bridge_insertion(handle);
 707                 break;
 708
 709         case ACPI_NOTIFY_EJECT_REQUEST:
 710                 /* request device eject */
 711                 printk(KERN_DEBUG "%s: Device eject notify on %s\n", __func__,
 712                                  (char *)buffer.pointer);
 713                 if (root)
 714                         handle_root_bridge_removal(root->device);
 715                 break;
 716         default:
 717                 printk(KERN_WARNING "notify_handler: unknown event type 0x%x for %s\n",
 718                                  type, (char *)buffer.pointer);
 719                 break;
 720         }
 721
 722         kfree(hp_work); /* allocated in handle_hotplug_event_bridge */
 723         kfree(buffer.pointer);
 724 }
 725
 726 static void handle_hotplug_event_root(acpi_handle handle, u32 type,
 727                                         void *context)
 728 {
 729         alloc_acpi_hp_work(handle, type, context,
 730                                 _handle_hotplug_event_root);
 731 }
 732
 733 static acpi_status __init
 734 find_root_bridges(acpi_handle handle, u32 lvl, void *context, void **rv)
 735 {
 736         acpi_status status;
 737         char objname[64];
 738         struct acpi_buffer buffer = { .length = sizeof(objname),
 739                                       .pointer = objname };
 740         int *count = (int *)context;
 741
 742         if (!acpi_is_root_bridge(handle))
 743                 return AE_OK;
 744
 745         (*count)++;
 746
 747         acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
 748
 749         status = acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
 750                                         handle_hotplug_event_root, NULL);
 751         if (ACPI_FAILURE(status))
 752                 printk(KERN_DEBUG "acpi root: %s notify handler is not installed, exit status: %u\n",
 753                                   objname, (unsigned int)status);
 754         else
 755                 printk(KERN_DEBUG "acpi root: %s notify handler is installed\n",
 756                                  objname);
 757
 758         return AE_OK;
 759 }
 760
 761 void __init acpi_pci_root_hp_init(void)
 762 {
 763         int num = 0;
 764
 765         acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
 766                 ACPI_UINT32_MAX, find_root_bridges, NULL, &num, NULL);
 767
 768         printk(KERN_DEBUG "Found %d acpi root devices\n", num);
 769 }