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) && (root->bus_nr == (u16) bus))
 124                         return root->device->handle;
 125         return NULL;
 126 }
 127
 128 EXPORT_SYMBOL_GPL(acpi_get_pci_rootbridge_handle);
 129
 130 /**
 131  * acpi_is_root_bridge - determine whether an ACPI CA node is a PCI root bridge
 132  * @handle - the ACPI CA node in question.
 133  *
 134  * Note: we could make this API take a struct acpi_device * instead, but
 135  * for now, it's more convenient to operate on an acpi_handle.
 136  */
 137 int acpi_is_root_bridge(acpi_handle handle)
 138 {
 139         int ret;
 140         struct acpi_device *device;
 141
 142         ret = acpi_bus_get_device(handle, &device);
 143         if (ret)
 144                 return 0;
 145
 146         ret = acpi_match_device_ids(device, root_device_ids);
 147         if (ret)
 148                 return 0;
 149         else
 150                 return 1;
 151 }
 152 EXPORT_SYMBOL_GPL(acpi_is_root_bridge);
 153
 154 static acpi_status
 155 get_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
 156 {
 157         int *busnr = data;
 158         struct acpi_resource_address64 address;
 159
 160         if (resource->type != ACPI_RESOURCE_TYPE_ADDRESS16 &&
 161             resource->type != ACPI_RESOURCE_TYPE_ADDRESS32 &&
 162             resource->type != ACPI_RESOURCE_TYPE_ADDRESS64)
 163                 return AE_OK;
 164
 165         acpi_resource_to_address64(resource, &address);
 166         if ((address.address_length > 0) &&
 167             (address.resource_type == ACPI_BUS_NUMBER_RANGE))
 168                 *busnr = address.minimum;
 169
 170         return AE_OK;
 171 }
 172
 173 static acpi_status try_get_root_bridge_busnr(acpi_handle handle,
 174                                              unsigned long long *bus)
 175 {
 176         acpi_status status;
 177         int busnum;
 178
 179         busnum = -1;
 180         status =
 181             acpi_walk_resources(handle, METHOD_NAME__CRS,
 182                                 get_root_bridge_busnr_callback, &busnum);
 183         if (ACPI_FAILURE(status))
 184                 return status;
 185         /* Check if we really get a bus number from _CRS */
 186         if (busnum == -1)
 187                 return AE_ERROR;
 188         *bus = busnum;
 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, u32 flags)
 229 {
 230         acpi_status status;
 231         u32 support_set, result, capbuf[3];
 232
 233         /* do _OSC query for all possible controls */
 234         support_set = root->osc_support_set | (flags & OSC_PCI_SUPPORT_MASKS);
 235         capbuf[OSC_QUERY_TYPE] = OSC_QUERY_ENABLE;
 236         capbuf[OSC_SUPPORT_TYPE] = support_set;
 237         capbuf[OSC_CONTROL_TYPE] = OSC_PCI_CONTROL_MASKS;
 238
 239         status = acpi_pci_run_osc(root->device->handle, capbuf, &result);
 240         if (ACPI_SUCCESS(status)) {
 241                 root->osc_support_set = support_set;
 242                 root->osc_control_qry = result;
 243                 root->osc_queried = 1;
 244         }
 245         return status;
 246 }
 247
 248 static acpi_status acpi_pci_osc_support(struct acpi_pci_root *root, u32 flags)
 249 {
 250         acpi_status status;
 251         acpi_handle tmp;
 252
 253         status = acpi_get_handle(root->device->handle, "_OSC", &tmp);
 254         if (ACPI_FAILURE(status))
 255                 return status;
 256         mutex_lock(&osc_lock);
 257         status = acpi_pci_query_osc(root, flags);
 258         mutex_unlock(&osc_lock);
 259         return status;
 260 }
 261
 262 struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle)
 263 {
 264         struct acpi_pci_root *root;
 265
 266         list_for_each_entry(root, &acpi_pci_roots, node) {
 267                 if (root->device->handle == handle)
 268                         return root;
 269         }
 270         return NULL;
 271 }
 272 EXPORT_SYMBOL_GPL(acpi_pci_find_root);
 273
 274 struct acpi_handle_node {
 275         struct list_head node;
 276         acpi_handle handle;
 277 };
 278
 279 /**
 280  * acpi_get_pci_dev - convert ACPI CA handle to struct pci_dev
 281  * @handle: the handle in question
 282  *
 283  * Given an ACPI CA handle, the desired PCI device is located in the
 284  * list of PCI devices.
 285  *
 286  * If the device is found, its reference count is increased and this
 287  * function returns a pointer to its data structure.  The caller must
 288  * decrement the reference count by calling pci_dev_put().
 289  * If no device is found, %NULL is returned.
 290  */
 291 struct pci_dev *acpi_get_pci_dev(acpi_handle handle)
 292 {
 293         int dev, fn;
 294         unsigned long long adr;
 295         acpi_status status;
 296         acpi_handle phandle;
 297         struct pci_bus *pbus;
 298         struct pci_dev *pdev = NULL;
 299         struct acpi_handle_node *node, *tmp;
 300         struct acpi_pci_root *root;
 301         LIST_HEAD(device_list);
 302
 303         /*
 304          * Walk up the ACPI CA namespace until we reach a PCI root bridge.
 305          */
 306         phandle = handle;
 307         while (!acpi_is_root_bridge(phandle)) {
 308                 node = kzalloc(sizeof(struct acpi_handle_node), GFP_KERNEL);
 309                 if (!node)
 310                         goto out;
 311
 312                 INIT_LIST_HEAD(&node->node);
 313                 node->handle = phandle;
 314                 list_add(&node->node, &device_list);
 315
 316                 status = acpi_get_parent(phandle, &phandle);
 317                 if (ACPI_FAILURE(status))
 318                         goto out;
 319         }
 320
 321         root = acpi_pci_find_root(phandle);
 322         if (!root)
 323                 goto out;
 324
 325         pbus = root->bus;
 326
 327         /*
 328          * Now, walk back down the PCI device tree until we return to our
 329          * original handle. Assumes that everything between the PCI root
 330          * bridge and the device we're looking for must be a P2P bridge.
 331          */
 332         list_for_each_entry(node, &device_list, node) {
 333                 acpi_handle hnd = node->handle;
 334                 status = acpi_evaluate_integer(hnd, "_ADR", NULL, &adr);
 335                 if (ACPI_FAILURE(status))
 336                         goto out;
 337                 dev = (adr >> 16) & 0xffff;
 338                 fn  = adr & 0xffff;
 339
 340                 pdev = pci_get_slot(pbus, PCI_DEVFN(dev, fn));
 341                 if (!pdev || hnd == handle)
 342                         break;
 343
 344                 pbus = pdev->subordinate;
 345                 pci_dev_put(pdev);
 346
 347                 /*
 348                  * This function may be called for a non-PCI device that has a
 349                  * PCI parent (eg. a disk under a PCI SATA controller).  In that
 350                  * case pdev->subordinate will be NULL for the parent.
 351                  */
 352                 if (!pbus) {
 353                         dev_dbg(&pdev->dev, "Not a PCI-to-PCI bridge\n");
 354                         pdev = NULL;
 355                         break;
 356                 }
 357         }
 358 out:
 359         list_for_each_entry_safe(node, tmp, &device_list, node)
 360                 kfree(node);
 361
 362         return pdev;
 363 }
 364 EXPORT_SYMBOL_GPL(acpi_get_pci_dev);
 365
 366 /**
 367  * acpi_pci_osc_control_set - commit requested control to Firmware
 368  * @handle: acpi_handle for the target ACPI object
 369  * @flags: driver's requested control bits
 370  *
 371  * Attempt to take control from Firmware on requested control bits.
 372  **/
 373 acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 flags)
 374 {
 375         acpi_status status;
 376         u32 control_req, result, capbuf[3];
 377         acpi_handle tmp;
 378         struct acpi_pci_root *root;
 379
 380         status = acpi_get_handle(handle, "_OSC", &tmp);
 381         if (ACPI_FAILURE(status))
 382                 return status;
 383
 384         control_req = (flags & OSC_PCI_CONTROL_MASKS);
 385         if (!control_req)
 386                 return AE_TYPE;
 387
 388         root = acpi_pci_find_root(handle);
 389         if (!root)
 390                 return AE_NOT_EXIST;
 391
 392         mutex_lock(&osc_lock);
 393         /* No need to evaluate _OSC if the control was already granted. */
 394         if ((root->osc_control_set & control_req) == control_req)
 395                 goto out;
 396
 397         /* Need to query controls first before requesting them */
 398         if (!root->osc_queried) {
 399                 status = acpi_pci_query_osc(root, root->osc_support_set);
 400                 if (ACPI_FAILURE(status))
 401                         goto out;
 402         }
 403         if ((root->osc_control_qry & control_req) != control_req) {
 404                 printk(KERN_DEBUG
 405                        "Firmware did not grant requested _OSC control\n");
 406                 status = AE_SUPPORT;
 407                 goto out;
 408         }
 409
 410         capbuf[OSC_QUERY_TYPE] = 0;
 411         capbuf[OSC_SUPPORT_TYPE] = root->osc_support_set;
 412         capbuf[OSC_CONTROL_TYPE] = root->osc_control_set | control_req;
 413         status = acpi_pci_run_osc(handle, capbuf, &result);
 414         if (ACPI_SUCCESS(status))
 415                 root->osc_control_set = result;
 416 out:
 417         mutex_unlock(&osc_lock);
 418         return status;
 419 }
 420 EXPORT_SYMBOL(acpi_pci_osc_control_set);
 421
 422 static int __devinit acpi_pci_root_add(struct acpi_device *device)
 423 {
 424         unsigned long long segment, bus;
 425         acpi_status status;
 426         int result;
 427         struct acpi_pci_root *root;
 428         acpi_handle handle;
 429         struct acpi_device *child;
 430         u32 flags, base_flags;
 431
 432         segment = 0;
 433         status = acpi_evaluate_integer(device->handle, METHOD_NAME__SEG, NULL,
 434                                        &segment);
 435         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 436                 printk(KERN_ERR PREFIX "can't evaluate _SEG\n");
 437                 return -ENODEV;
 438         }
 439
 440         /* Check _CRS first, then _BBN.  If no _BBN, default to zero. */
 441         bus = 0;
 442         status = try_get_root_bridge_busnr(device->handle, &bus);
 443         if (ACPI_FAILURE(status)) {
 444                 status = acpi_evaluate_integer(device->handle, METHOD_NAME__BBN,                                               NULL, &bus);
 445                 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 446                         printk(KERN_ERR PREFIX
 447                              "no bus number in _CRS and can't evaluate _BBN\n");
 448                         return -ENODEV;
 449                 }
 450         }
 451
 452         root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
 453         if (!root)
 454                 return -ENOMEM;
 455
 456         INIT_LIST_HEAD(&root->node);
 457         root->device = device;
 458         root->segment = segment & 0xFFFF;
 459         root->bus_nr = bus & 0xFF;
 460         strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
 461         strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
 462         device->driver_data = root;
 463
 464         /*
 465          * All supported architectures that use ACPI have support for
 466          * PCI domains, so we indicate this in _OSC support capabilities.
 467          */
 468         flags = base_flags = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
 469         acpi_pci_osc_support(root, flags);
 470
 471         /*
 472          * TBD: Need PCI interface for enumeration/configuration of roots.
 473          */
 474
 475         /* TBD: Locking */
 476         list_add_tail(&root->node, &acpi_pci_roots);
 477
 478         printk(KERN_INFO PREFIX "%s [%s] (%04x:%02x)\n",
 479                acpi_device_name(device), acpi_device_bid(device),
 480                root->segment, root->bus_nr);
 481
 482         /*
 483          * Scan the Root Bridge
 484          * --------------------
 485          * Must do this prior to any attempt to bind the root device, as the
 486          * PCI namespace does not get created until this call is made (and
 487          * thus the root bridge's pci_dev does not exist).
 488          */
 489         root->bus = pci_acpi_scan_root(device, segment, bus);
 490         if (!root->bus) {
 491                 printk(KERN_ERR PREFIX
 492                             "Bus %04x:%02x not present in PCI namespace\n",
 493                             root->segment, root->bus_nr);
 494                 result = -ENODEV;
 495                 goto end;
 496         }
 497
 498         /*
 499          * Attach ACPI-PCI Context
 500          * -----------------------
 501          * Thus binding the ACPI and PCI devices.
 502          */
 503         result = acpi_pci_bind_root(device);
 504         if (result)
 505                 goto end;
 506
 507         /*
 508          * PCI Routing Table
 509          * -----------------
 510          * Evaluate and parse _PRT, if exists.
 511          */
 512         status = acpi_get_handle(device->handle, METHOD_NAME__PRT, &handle);
 513         if (ACPI_SUCCESS(status))
 514                 result = acpi_pci_irq_add_prt(device->handle, root->bus);
 515
 516         /*
 517          * Scan and bind all _ADR-Based Devices
 518          */
 519         list_for_each_entry(child, &device->children, node)
 520                 acpi_pci_bridge_scan(child);
 521
 522         /* Indicate support for various _OSC capabilities. */
 523         if (pci_ext_cfg_avail(root->bus->self))
 524                 flags |= OSC_EXT_PCI_CONFIG_SUPPORT;
 525         if (pcie_aspm_enabled())
 526                 flags |= OSC_ACTIVE_STATE_PWR_SUPPORT |
 527                         OSC_CLOCK_PWR_CAPABILITY_SUPPORT;
 528         if (pci_msi_enabled())
 529                 flags |= OSC_MSI_SUPPORT;
 530         if (flags != base_flags)
 531                 acpi_pci_osc_support(root, flags);
 532
 533         pci_acpi_add_bus_pm_notifier(device, root->bus);
 534         if (device->wakeup.flags.run_wake)
 535                 device_set_run_wake(root->bus->bridge, true);
 536
 537         return 0;
 538
 539 end:
 540         if (!list_empty(&root->node))
 541                 list_del(&root->node);
 542         kfree(root);
 543         return result;
 544 }
 545
 546 static int acpi_pci_root_start(struct acpi_device *device)
 547 {
 548         struct acpi_pci_root *root = acpi_driver_data(device);
 549
 550         pci_bus_add_devices(root->bus);
 551         return 0;
 552 }
 553
 554 static int acpi_pci_root_remove(struct acpi_device *device, int type)
 555 {
 556         struct acpi_pci_root *root = acpi_driver_data(device);
 557
 558         device_set_run_wake(root->bus->bridge, false);
 559         pci_acpi_remove_bus_pm_notifier(device);
 560
 561         kfree(root);
 562         return 0;
 563 }
 564
 565 static int __init acpi_pci_root_init(void)
 566 {
 567         if (acpi_pci_disabled)
 568                 return 0;
 569
 570         pci_acpi_crs_quirks();
 571         if (acpi_bus_register_driver(&acpi_pci_root_driver) < 0)
 572                 return -ENODEV;
 573
 574         return 0;
 575 }
 576
 577 subsys_initcall(acpi_pci_root_init);