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