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/proc_fs.h>
  31 #include <linux/spinlock.h>
  32 #include <linux/pm.h>
  33 #include <linux/pm_runtime.h>
  34 #include <linux/pci.h>
  35 #include <linux/pci-acpi.h>
  36 #include <linux/acpi.h>
  37 #include <linux/slab.h>
  38 #include <acpi/acpi_bus.h>
  39 #include <acpi/acpi_drivers.h>
  40
  41 #define PREFIX "ACPI: "
  42
  43 #define _COMPONENT              ACPI_PCI_COMPONENT
  44 ACPI_MODULE_NAME("pci_root");
  45 #define ACPI_PCI_ROOT_CLASS             "pci_bridge"
  46 #define ACPI_PCI_ROOT_DEVICE_NAME       "PCI Root Bridge"
  47 static int acpi_pci_root_add(struct acpi_device *device);
  48 static int acpi_pci_root_remove(struct acpi_device *device, int type);
  49 static int acpi_pci_root_start(struct acpi_device *device);
  50
  51 static const struct acpi_device_id root_device_ids[] = {
  52         {"PNP0A03", 0},
  53         {"", 0},
  54 };
  55 MODULE_DEVICE_TABLE(acpi, root_device_ids);
  56
  57 static struct acpi_driver acpi_pci_root_driver = {
  58         .name = "pci_root",
  59         .class = ACPI_PCI_ROOT_CLASS,
  60         .ids = root_device_ids,
  61         .ops = {
  62                 .add = acpi_pci_root_add,
  63                 .remove = acpi_pci_root_remove,
  64                 .start = acpi_pci_root_start,
  65                 },
  66 };
  67
  68 static LIST_HEAD(acpi_pci_roots);
  69
  70 static struct acpi_pci_driver *sub_driver;
  71 static DEFINE_MUTEX(osc_lock);
  72
  73 int acpi_pci_register_driver(struct acpi_pci_driver *driver)
  74 {
  75         int n = 0;
  76         struct acpi_pci_root *root;
  77
  78         struct acpi_pci_driver **pptr = &sub_driver;
  79         while (*pptr)
  80                 pptr = &(*pptr)->next;
  81         *pptr = driver;
  82
  83         if (!driver->add)
  84                 return 0;
  85
  86         list_for_each_entry(root, &acpi_pci_roots, node) {
  87                 driver->add(root->device->handle);
  88                 n++;
  89         }
  90
  91         return n;
  92 }
  93
  94 EXPORT_SYMBOL(acpi_pci_register_driver);
  95
  96 void acpi_pci_unregister_driver(struct acpi_pci_driver *driver)
  97 {
  98         struct acpi_pci_root *root;
  99
 100         struct acpi_pci_driver **pptr = &sub_driver;
 101         while (*pptr) {
 102                 if (*pptr == driver)
 103                         break;
 104                 pptr = &(*pptr)->next;
 105         }
 106         BUG_ON(!*pptr);
 107         *pptr = (*pptr)->next;
 108
 109         if (!driver->remove)
 110                 return;
 111
 112         list_for_each_entry(root, &acpi_pci_roots, node)
 113                 driver->remove(root->device->handle);
 114 }
 115
 116 EXPORT_SYMBOL(acpi_pci_unregister_driver);
 117
 118 acpi_handle acpi_get_pci_rootbridge_handle(unsigned int seg, unsigned int bus)
 119 {
 120         struct acpi_pci_root *root;
 121
 122         list_for_each_entry(root, &acpi_pci_roots, node)
 123                 if ((root->segment == (u16) seg) &&
 124                     (root->secondary.start == (u16) bus))
 125                         return root->device->handle;
 126         return NULL;
 127 }
 128
 129 EXPORT_SYMBOL_GPL(acpi_get_pci_rootbridge_handle);
 130
 131 /**
 132  * acpi_is_root_bridge - determine whether an ACPI CA node is a PCI root bridge
 133  * @handle - the ACPI CA node in question.
 134  *
 135  * Note: we could make this API take a struct acpi_device * instead, but
 136  * for now, it's more convenient to operate on an acpi_handle.
 137  */
 138 int acpi_is_root_bridge(acpi_handle handle)
 139 {
 140         int ret;
 141         struct acpi_device *device;
 142
 143         ret = acpi_bus_get_device(handle, &device);
 144         if (ret)
 145                 return 0;
 146
 147         ret = acpi_match_device_ids(device, root_device_ids);
 148         if (ret)
 149                 return 0;
 150         else
 151                 return 1;
 152 }
 153 EXPORT_SYMBOL_GPL(acpi_is_root_bridge);
 154
 155 static acpi_status
 156 get_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
 157 {
 158         struct resource *res = data;
 159         struct acpi_resource_address64 address;
 160
 161         if (resource->type != ACPI_RESOURCE_TYPE_ADDRESS16 &&
 162             resource->type != ACPI_RESOURCE_TYPE_ADDRESS32 &&
 163             resource->type != ACPI_RESOURCE_TYPE_ADDRESS64)
 164                 return AE_OK;
 165
 166         acpi_resource_to_address64(resource, &address);
 167         if ((address.address_length > 0) &&
 168             (address.resource_type == ACPI_BUS_NUMBER_RANGE)) {
 169                 res->start = address.minimum;
 170                 res->end = address.minimum + address.address_length - 1;
 171         }
 172
 173         return AE_OK;
 174 }
 175
 176 static acpi_status try_get_root_bridge_busnr(acpi_handle handle,
 177                                              struct resource *res)
 178 {
 179         acpi_status status;
 180
 181         res->start = -1;
 182         status =
 183             acpi_walk_resources(handle, METHOD_NAME__CRS,
 184                                 get_root_bridge_busnr_callback, res);
 185         if (ACPI_FAILURE(status))
 186                 return status;
 187         if (res->start == -1)
 188                 return AE_ERROR;
 189         return AE_OK;
 190 }
 191
 192 static void acpi_pci_bridge_scan(struct acpi_device *device)
 193 {
 194         int status;
 195         struct acpi_device *child = NULL;
 196
 197         if (device->flags.bus_address)
 198                 if (device->parent && device->parent->ops.bind) {
 199                         status = device->parent->ops.bind(device);
 200                         if (!status) {
 201                                 list_for_each_entry(child, &device->children, node)
 202                                         acpi_pci_bridge_scan(child);
 203                         }
 204                 }
 205 }
 206
 207 static u8 pci_osc_uuid_str[] = "33DB4D5B-1FF7-401C-9657-7441C03DD766";
 208
 209 static acpi_status acpi_pci_run_osc(acpi_handle handle,
 210                                     const u32 *capbuf, u32 *retval)
 211 {
 212         struct acpi_osc_context context = {
 213                 .uuid_str = pci_osc_uuid_str,
 214                 .rev = 1,
 215                 .cap.length = 12,
 216                 .cap.pointer = (void *)capbuf,
 217         };
 218         acpi_status status;
 219
 220         status = acpi_run_osc(handle, &context);
 221         if (ACPI_SUCCESS(status)) {
 222                 *retval = *((u32 *)(context.ret.pointer + 8));
 223                 kfree(context.ret.pointer);
 224         }
 225         return status;
 226 }
 227
 228 static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root,
 229                                         u32 support,
 230                                         u32 *control)
 231 {
 232         acpi_status status;
 233         u32 result, capbuf[3];
 234
 235         support &= OSC_PCI_SUPPORT_MASKS;
 236         support |= root->osc_support_set;
 237
 238         capbuf[OSC_QUERY_TYPE] = OSC_QUERY_ENABLE;
 239         capbuf[OSC_SUPPORT_TYPE] = support;
 240         if (control) {
 241                 *control &= OSC_PCI_CONTROL_MASKS;
 242                 capbuf[OSC_CONTROL_TYPE] = *control | root->osc_control_set;
 243         } else {
 244                 /* Run _OSC query for all possible controls. */
 245                 capbuf[OSC_CONTROL_TYPE] = OSC_PCI_CONTROL_MASKS;
 246         }
 247
 248         status = acpi_pci_run_osc(root->device->handle, capbuf, &result);
 249         if (ACPI_SUCCESS(status)) {
 250                 root->osc_support_set = support;
 251                 if (control)
 252                         *control = result;
 253         }
 254         return status;
 255 }
 256
 257 static acpi_status acpi_pci_osc_support(struct acpi_pci_root *root, u32 flags)
 258 {
 259         acpi_status status;
 260         acpi_handle tmp;
 261
 262         status = acpi_get_handle(root->device->handle, "_OSC", &tmp);
 263         if (ACPI_FAILURE(status))
 264                 return status;
 265         mutex_lock(&osc_lock);
 266         status = acpi_pci_query_osc(root, flags, NULL);
 267         mutex_unlock(&osc_lock);
 268         return status;
 269 }
 270
 271 struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle)
 272 {
 273         struct acpi_pci_root *root;
 274
 275         list_for_each_entry(root, &acpi_pci_roots, node) {
 276                 if (root->device->handle == handle)
 277                         return root;
 278         }
 279         return NULL;
 280 }
 281 EXPORT_SYMBOL_GPL(acpi_pci_find_root);
 282
 283 struct acpi_handle_node {
 284         struct list_head node;
 285         acpi_handle handle;
 286 };
 287
 288 /**
 289  * acpi_get_pci_dev - convert ACPI CA handle to struct pci_dev
 290  * @handle: the handle in question
 291  *
 292  * Given an ACPI CA handle, the desired PCI device is located in the
 293  * list of PCI devices.
 294  *
 295  * If the device is found, its reference count is increased and this
 296  * function returns a pointer to its data structure.  The caller must
 297  * decrement the reference count by calling pci_dev_put().
 298  * If no device is found, %NULL is returned.
 299  */
 300 struct pci_dev *acpi_get_pci_dev(acpi_handle handle)
 301 {
 302         int dev, fn;
 303         unsigned long long adr;
 304         acpi_status status;
 305         acpi_handle phandle;
 306         struct pci_bus *pbus;
 307         struct pci_dev *pdev = NULL;
 308         struct acpi_handle_node *node, *tmp;
 309         struct acpi_pci_root *root;
 310         LIST_HEAD(device_list);
 311
 312         /*
 313          * Walk up the ACPI CA namespace until we reach a PCI root bridge.
 314          */
 315         phandle = handle;
 316         while (!acpi_is_root_bridge(phandle)) {
 317                 node = kzalloc(sizeof(struct acpi_handle_node), GFP_KERNEL);
 318                 if (!node)
 319                         goto out;
 320
 321                 INIT_LIST_HEAD(&node->node);
 322                 node->handle = phandle;
 323                 list_add(&node->node, &device_list);
 324
 325                 status = acpi_get_parent(phandle, &phandle);
 326                 if (ACPI_FAILURE(status))
 327                         goto out;
 328         }
 329
 330         root = acpi_pci_find_root(phandle);
 331         if (!root)
 332                 goto out;
 333
 334         pbus = root->bus;
 335
 336         /*
 337          * Now, walk back down the PCI device tree until we return to our
 338          * original handle. Assumes that everything between the PCI root
 339          * bridge and the device we're looking for must be a P2P bridge.
 340          */
 341         list_for_each_entry(node, &device_list, node) {
 342                 acpi_handle hnd = node->handle;
 343                 status = acpi_evaluate_integer(hnd, "_ADR", NULL, &adr);
 344                 if (ACPI_FAILURE(status))
 345                         goto out;
 346                 dev = (adr >> 16) & 0xffff;
 347                 fn  = adr & 0xffff;
 348
 349                 pdev = pci_get_slot(pbus, PCI_DEVFN(dev, fn));
 350                 if (!pdev || hnd == handle)
 351                         break;
 352
 353                 pbus = pdev->subordinate;
 354                 pci_dev_put(pdev);
 355
 356                 /*
 357                  * This function may be called for a non-PCI device that has a
 358                  * PCI parent (eg. a disk under a PCI SATA controller).  In that
 359                  * case pdev->subordinate will be NULL for the parent.
 360                  */
 361                 if (!pbus) {
 362                         dev_dbg(&pdev->dev, "Not a PCI-to-PCI bridge\n");
 363                         pdev = NULL;
 364                         break;
 365                 }
 366         }
 367 out:
 368         list_for_each_entry_safe(node, tmp, &device_list, node)
 369                 kfree(node);
 370
 371         return pdev;
 372 }
 373 EXPORT_SYMBOL_GPL(acpi_get_pci_dev);
 374
 375 /**
 376  * acpi_pci_osc_control_set - Request control of PCI root _OSC features.
 377  * @handle: ACPI handle of a PCI root bridge (or PCIe Root Complex).
 378  * @mask: Mask of _OSC bits to request control of, place to store control mask.
 379  * @req: Mask of _OSC bits the control of is essential to the caller.
 380  *
 381  * Run _OSC query for @mask and if that is successful, compare the returned
 382  * mask of control bits with @req.  If all of the @req bits are set in the
 383  * returned mask, run _OSC request for it.
 384  *
 385  * The variable at the @mask address may be modified regardless of whether or
 386  * not the function returns success.  On success it will contain the mask of
 387  * _OSC bits the BIOS has granted control of, but its contents are meaningless
 388  * on failure.
 389  **/
 390 acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 *mask, u32 req)
 391 {
 392         struct acpi_pci_root *root;
 393         acpi_status status;
 394         u32 ctrl, capbuf[3];
 395         acpi_handle tmp;
 396
 397         if (!mask)
 398                 return AE_BAD_PARAMETER;
 399
 400         ctrl = *mask & OSC_PCI_CONTROL_MASKS;
 401         if ((ctrl & req) != req)
 402                 return AE_TYPE;
 403
 404         root = acpi_pci_find_root(handle);
 405         if (!root)
 406                 return AE_NOT_EXIST;
 407
 408         status = acpi_get_handle(handle, "_OSC", &tmp);
 409         if (ACPI_FAILURE(status))
 410                 return status;
 411
 412         mutex_lock(&osc_lock);
 413
 414         *mask = ctrl | root->osc_control_set;
 415         /* No need to evaluate _OSC if the control was already granted. */
 416         if ((root->osc_control_set & ctrl) == ctrl)
 417                 goto out;
 418
 419         /* Need to check the available controls bits before requesting them. */
 420         while (*mask) {
 421                 status = acpi_pci_query_osc(root, root->osc_support_set, mask);
 422                 if (ACPI_FAILURE(status))
 423                         goto out;
 424                 if (ctrl == *mask)
 425                         break;
 426                 ctrl = *mask;
 427         }
 428
 429         if ((ctrl & req) != req) {
 430                 status = AE_SUPPORT;
 431                 goto out;
 432         }
 433
 434         capbuf[OSC_QUERY_TYPE] = 0;
 435         capbuf[OSC_SUPPORT_TYPE] = root->osc_support_set;
 436         capbuf[OSC_CONTROL_TYPE] = ctrl;
 437         status = acpi_pci_run_osc(handle, capbuf, mask);
 438         if (ACPI_SUCCESS(status))
 439                 root->osc_control_set = *mask;
 440 out:
 441         mutex_unlock(&osc_lock);
 442         return status;
 443 }
 444 EXPORT_SYMBOL(acpi_pci_osc_control_set);
 445
 446 static int __devinit acpi_pci_root_add(struct acpi_device *device)
 447 {
 448         unsigned long long segment, bus;
 449         acpi_status status;
 450         int result;
 451         struct acpi_pci_root *root;
 452         acpi_handle handle;
 453         struct acpi_device *child;
 454         u32 flags, base_flags;
 455
 456         root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
 457         if (!root)
 458                 return -ENOMEM;
 459
 460         segment = 0;
 461         status = acpi_evaluate_integer(device->handle, METHOD_NAME__SEG, NULL,
 462                                        &segment);
 463         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 464                 printk(KERN_ERR PREFIX "can't evaluate _SEG\n");
 465                 result = -ENODEV;
 466                 goto end;
 467         }
 468
 469         /* Check _CRS first, then _BBN.  If no _BBN, default to zero. */
 470         root->secondary.flags = IORESOURCE_BUS;
 471         status = try_get_root_bridge_busnr(device->handle, &root->secondary);
 472         if (ACPI_FAILURE(status)) {
 473                 /*
 474                  * We need both the start and end of the downstream bus range
 475                  * to interpret _CBA (MMCONFIG base address), so it really is
 476                  * supposed to be in _CRS.  If we don't find it there, all we
 477                  * can do is assume [_BBN-0xFF] or [0-0xFF].
 478                  */
 479                 root->secondary.end = 0xFF;
 480                 printk(KERN_WARNING FW_BUG PREFIX
 481                        "no secondary bus range in _CRS\n");
 482                 status = acpi_evaluate_integer(device->handle, METHOD_NAME__BBN,                                               NULL, &bus);
 483                 if (ACPI_SUCCESS(status))
 484                         root->secondary.start = bus;
 485                 else if (status == AE_NOT_FOUND)
 486                         root->secondary.start = 0;
 487                 else {
 488                         printk(KERN_ERR PREFIX "can't evaluate _BBN\n");
 489                         result = -ENODEV;
 490                         goto end;
 491                 }
 492         }
 493
 494         INIT_LIST_HEAD(&root->node);
 495         root->device = device;
 496         root->segment = segment & 0xFFFF;
 497         strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
 498         strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
 499         device->driver_data = root;
 500
 501         /*
 502          * All supported architectures that use ACPI have support for
 503          * PCI domains, so we indicate this in _OSC support capabilities.
 504          */
 505         flags = base_flags = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
 506         acpi_pci_osc_support(root, flags);
 507
 508         /*
 509          * TBD: Need PCI interface for enumeration/configuration of roots.
 510          */
 511
 512         /* TBD: Locking */
 513         list_add_tail(&root->node, &acpi_pci_roots);
 514
 515         printk(KERN_INFO PREFIX "%s [%s] (domain %04x %pR)\n",
 516                acpi_device_name(device), acpi_device_bid(device),
 517                root->segment, &root->secondary);
 518
 519         /*
 520          * Scan the Root Bridge
 521          * --------------------
 522          * Must do this prior to any attempt to bind the root device, as the
 523          * PCI namespace does not get created until this call is made (and
 524          * thus the root bridge's pci_dev does not exist).
 525          */
 526         root->bus = pci_acpi_scan_root(root);
 527         if (!root->bus) {
 528                 printk(KERN_ERR PREFIX
 529                             "Bus %04x:%02x not present in PCI namespace\n",
 530                             root->segment, (unsigned int)root->secondary.start);
 531                 result = -ENODEV;
 532                 goto end;
 533         }
 534
 535         /*
 536          * Attach ACPI-PCI Context
 537          * -----------------------
 538          * Thus binding the ACPI and PCI devices.
 539          */
 540         result = acpi_pci_bind_root(device);
 541         if (result)
 542                 goto end;
 543
 544         /*
 545          * PCI Routing Table
 546          * -----------------
 547          * Evaluate and parse _PRT, if exists.
 548          */
 549         status = acpi_get_handle(device->handle, METHOD_NAME__PRT, &handle);
 550         if (ACPI_SUCCESS(status))
 551                 result = acpi_pci_irq_add_prt(device->handle, root->bus);
 552
 553         /*
 554          * Scan and bind all _ADR-Based Devices
 555          */
 556         list_for_each_entry(child, &device->children, node)
 557                 acpi_pci_bridge_scan(child);
 558
 559         /* Indicate support for various _OSC capabilities. */
 560         if (pci_ext_cfg_avail(root->bus->self))
 561                 flags |= OSC_EXT_PCI_CONFIG_SUPPORT;
 562         if (pcie_aspm_enabled())
 563                 flags |= OSC_ACTIVE_STATE_PWR_SUPPORT |
 564                         OSC_CLOCK_PWR_CAPABILITY_SUPPORT;
 565         if (pci_msi_enabled())
 566                 flags |= OSC_MSI_SUPPORT;
 567         if (flags != base_flags)
 568                 acpi_pci_osc_support(root, flags);
 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         return 0;
 575
 576 end:
 577         if (!list_empty(&root->node))
 578                 list_del(&root->node);
 579         kfree(root);
 580         return result;
 581 }
 582
 583 static int acpi_pci_root_start(struct acpi_device *device)
 584 {
 585         struct acpi_pci_root *root = acpi_driver_data(device);
 586
 587         pci_bus_add_devices(root->bus);
 588         return 0;
 589 }
 590
 591 static int acpi_pci_root_remove(struct acpi_device *device, int type)
 592 {
 593         struct acpi_pci_root *root = acpi_driver_data(device);
 594
 595         device_set_run_wake(root->bus->bridge, false);
 596         pci_acpi_remove_bus_pm_notifier(device);
 597
 598         kfree(root);
 599         return 0;
 600 }
 601
 602 static int __init acpi_pci_root_init(void)
 603 {
 604         if (acpi_pci_disabled)
 605                 return 0;
 606
 607         pci_acpi_crs_quirks();
 608         if (acpi_bus_register_driver(&acpi_pci_root_driver) < 0)
 609                 return -ENODEV;
 610
 611         return 0;
 612 }
 613
 614 subsys_initcall(acpi_pci_root_init);