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 _COMPONENT              ACPI_PCI_COMPONENT
  40 ACPI_MODULE_NAME("pci_root");
  41 #define ACPI_PCI_ROOT_CLASS             "pci_bridge"
  42 #define ACPI_PCI_ROOT_DEVICE_NAME       "PCI Root Bridge"
  43 static int acpi_pci_root_add(struct acpi_device *device);
  44 static int acpi_pci_root_remove(struct acpi_device *device, int type);
  45 static int acpi_pci_root_start(struct acpi_device *device);
  46
  47 static struct acpi_device_id root_device_ids[] = {
  48         {"PNP0A03", 0},
  49         {"", 0},
  50 };
  51 MODULE_DEVICE_TABLE(acpi, root_device_ids);
  52
  53 static struct acpi_driver acpi_pci_root_driver = {
  54         .name = "pci_root",
  55         .class = ACPI_PCI_ROOT_CLASS,
  56         .ids = root_device_ids,
  57         .ops = {
  58                 .add = acpi_pci_root_add,
  59                 .remove = acpi_pci_root_remove,
  60                 .start = acpi_pci_root_start,
  61                 },
  62 };
  63
  64 static LIST_HEAD(acpi_pci_roots);
  65
  66 static struct acpi_pci_driver *sub_driver;
  67 static DEFINE_MUTEX(osc_lock);
  68
  69 int acpi_pci_register_driver(struct acpi_pci_driver *driver)
  70 {
  71         int n = 0;
  72         struct acpi_pci_root *root;
  73
  74         struct acpi_pci_driver **pptr = &sub_driver;
  75         while (*pptr)
  76                 pptr = &(*pptr)->next;
  77         *pptr = driver;
  78
  79         if (!driver->add)
  80                 return 0;
  81
  82         list_for_each_entry(root, &acpi_pci_roots, node) {
  83                 driver->add(root->device->handle);
  84                 n++;
  85         }
  86
  87         return n;
  88 }
  89
  90 EXPORT_SYMBOL(acpi_pci_register_driver);
  91
  92 void acpi_pci_unregister_driver(struct acpi_pci_driver *driver)
  93 {
  94         struct acpi_pci_root *root;
  95
  96         struct acpi_pci_driver **pptr = &sub_driver;
  97         while (*pptr) {
  98                 if (*pptr == driver)
  99                         break;
 100                 pptr = &(*pptr)->next;
 101         }
 102         BUG_ON(!*pptr);
 103         *pptr = (*pptr)->next;
 104
 105         if (!driver->remove)
 106                 return;
 107
 108         list_for_each_entry(root, &acpi_pci_roots, node)
 109                 driver->remove(root->device->handle);
 110 }
 111
 112 EXPORT_SYMBOL(acpi_pci_unregister_driver);
 113
 114 acpi_handle acpi_get_pci_rootbridge_handle(unsigned int seg, unsigned int bus)
 115 {
 116         struct acpi_pci_root *root;
 117
 118         list_for_each_entry(root, &acpi_pci_roots, node)
 119                 if ((root->segment == (u16) seg) && (root->bus_nr == (u16) bus))
 120                         return root->device->handle;
 121         return NULL;
 122 }
 123
 124 EXPORT_SYMBOL_GPL(acpi_get_pci_rootbridge_handle);
 125
 126 /**
 127  * acpi_is_root_bridge - determine whether an ACPI CA node is a PCI root bridge
 128  * @handle - the ACPI CA node in question.
 129  *
 130  * Note: we could make this API take a struct acpi_device * instead, but
 131  * for now, it's more convenient to operate on an acpi_handle.
 132  */
 133 int acpi_is_root_bridge(acpi_handle handle)
 134 {
 135         int ret;
 136         struct acpi_device *device;
 137
 138         ret = acpi_bus_get_device(handle, &device);
 139         if (ret)
 140                 return 0;
 141
 142         ret = acpi_match_device_ids(device, root_device_ids);
 143         if (ret)
 144                 return 0;
 145         else
 146                 return 1;
 147 }
 148 EXPORT_SYMBOL_GPL(acpi_is_root_bridge);
 149
 150 static acpi_status
 151 get_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
 152 {
 153         int *busnr = data;
 154         struct acpi_resource_address64 address;
 155
 156         if (resource->type != ACPI_RESOURCE_TYPE_ADDRESS16 &&
 157             resource->type != ACPI_RESOURCE_TYPE_ADDRESS32 &&
 158             resource->type != ACPI_RESOURCE_TYPE_ADDRESS64)
 159                 return AE_OK;
 160
 161         acpi_resource_to_address64(resource, &address);
 162         if ((address.address_length > 0) &&
 163             (address.resource_type == ACPI_BUS_NUMBER_RANGE))
 164                 *busnr = address.minimum;
 165
 166         return AE_OK;
 167 }
 168
 169 static acpi_status try_get_root_bridge_busnr(acpi_handle handle,
 170                                              unsigned long long *bus)
 171 {
 172         acpi_status status;
 173         int busnum;
 174
 175         busnum = -1;
 176         status =
 177             acpi_walk_resources(handle, METHOD_NAME__CRS,
 178                                 get_root_bridge_busnr_callback, &busnum);
 179         if (ACPI_FAILURE(status))
 180                 return status;
 181         /* Check if we really get a bus number from _CRS */
 182         if (busnum == -1)
 183                 return AE_ERROR;
 184         *bus = busnum;
 185         return AE_OK;
 186 }
 187
 188 static void acpi_pci_bridge_scan(struct acpi_device *device)
 189 {
 190         int status;
 191         struct acpi_device *child = NULL;
 192
 193         if (device->flags.bus_address)
 194                 if (device->parent && device->parent->ops.bind) {
 195                         status = device->parent->ops.bind(device);
 196                         if (!status) {
 197                                 list_for_each_entry(child, &device->children, node)
 198                                         acpi_pci_bridge_scan(child);
 199                         }
 200                 }
 201 }
 202
 203 static u8 OSC_UUID[16] = {0x5B, 0x4D, 0xDB, 0x33, 0xF7, 0x1F, 0x1C, 0x40,
 204                           0x96, 0x57, 0x74, 0x41, 0xC0, 0x3D, 0xD7, 0x66};
 205
 206 static acpi_status acpi_pci_run_osc(acpi_handle handle,
 207                                     const u32 *capbuf, u32 *retval)
 208 {
 209         acpi_status status;
 210         struct acpi_object_list input;
 211         union acpi_object in_params[4];
 212         struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL};
 213         union acpi_object *out_obj;
 214         u32 errors;
 215
 216         /* Setting up input parameters */
 217         input.count = 4;
 218         input.pointer = in_params;
 219         in_params[0].type               = ACPI_TYPE_BUFFER;
 220         in_params[0].buffer.length      = 16;
 221         in_params[0].buffer.pointer     = OSC_UUID;
 222         in_params[1].type               = ACPI_TYPE_INTEGER;
 223         in_params[1].integer.value      = 1;
 224         in_params[2].type               = ACPI_TYPE_INTEGER;
 225         in_params[2].integer.value      = 3;
 226         in_params[3].type               = ACPI_TYPE_BUFFER;
 227         in_params[3].buffer.length      = 12;
 228         in_params[3].buffer.pointer     = (u8 *)capbuf;
 229
 230         status = acpi_evaluate_object(handle, "_OSC", &input, &output);
 231         if (ACPI_FAILURE(status))
 232                 return status;
 233
 234         if (!output.length)
 235                 return AE_NULL_OBJECT;
 236
 237         out_obj = output.pointer;
 238         if (out_obj->type != ACPI_TYPE_BUFFER) {
 239                 printk(KERN_DEBUG "_OSC evaluation returned wrong type\n");
 240                 status = AE_TYPE;
 241                 goto out_kfree;
 242         }
 243         /* Need to ignore the bit0 in result code */
 244         errors = *((u32 *)out_obj->buffer.pointer) & ~(1 << 0);
 245         if (errors) {
 246                 if (errors & OSC_REQUEST_ERROR)
 247                         printk(KERN_DEBUG "_OSC request failed\n");
 248                 if (errors & OSC_INVALID_UUID_ERROR)
 249                         printk(KERN_DEBUG "_OSC invalid UUID\n");
 250                 if (errors & OSC_INVALID_REVISION_ERROR)
 251                         printk(KERN_DEBUG "_OSC invalid revision\n");
 252                 if (errors & OSC_CAPABILITIES_MASK_ERROR) {
 253                         if (capbuf[OSC_QUERY_TYPE] & OSC_QUERY_ENABLE)
 254                                 goto out_success;
 255                         printk(KERN_DEBUG
 256                                "Firmware did not grant requested _OSC control\n");
 257                         status = AE_SUPPORT;
 258                         goto out_kfree;
 259                 }
 260                 status = AE_ERROR;
 261                 goto out_kfree;
 262         }
 263 out_success:
 264         *retval = *((u32 *)(out_obj->buffer.pointer + 8));
 265         status = AE_OK;
 266
 267 out_kfree:
 268         kfree(output.pointer);
 269         return status;
 270 }
 271
 272 static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root, u32 flags)
 273 {
 274         acpi_status status;
 275         u32 support_set, result, capbuf[3];
 276
 277         /* do _OSC query for all possible controls */
 278         support_set = root->osc_support_set | (flags & OSC_SUPPORT_MASKS);
 279         capbuf[OSC_QUERY_TYPE] = OSC_QUERY_ENABLE;
 280         capbuf[OSC_SUPPORT_TYPE] = support_set;
 281         capbuf[OSC_CONTROL_TYPE] = OSC_CONTROL_MASKS;
 282
 283         status = acpi_pci_run_osc(root->device->handle, capbuf, &result);
 284         if (ACPI_SUCCESS(status)) {
 285                 root->osc_support_set = support_set;
 286                 root->osc_control_qry = result;
 287                 root->osc_queried = 1;
 288         }
 289         return status;
 290 }
 291
 292 static acpi_status acpi_pci_osc_support(struct acpi_pci_root *root, u32 flags)
 293 {
 294         acpi_status status;
 295         acpi_handle tmp;
 296
 297         status = acpi_get_handle(root->device->handle, "_OSC", &tmp);
 298         if (ACPI_FAILURE(status))
 299                 return status;
 300         mutex_lock(&osc_lock);
 301         status = acpi_pci_query_osc(root, flags);
 302         mutex_unlock(&osc_lock);
 303         return status;
 304 }
 305
 306 struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle)
 307 {
 308         struct acpi_pci_root *root;
 309
 310         list_for_each_entry(root, &acpi_pci_roots, node) {
 311                 if (root->device->handle == handle)
 312                         return root;
 313         }
 314         return NULL;
 315 }
 316 EXPORT_SYMBOL_GPL(acpi_pci_find_root);
 317
 318 struct acpi_handle_node {
 319         struct list_head node;
 320         acpi_handle handle;
 321 };
 322
 323 /**
 324  * acpi_get_pci_dev - convert ACPI CA handle to struct pci_dev
 325  * @handle: the handle in question
 326  *
 327  * Given an ACPI CA handle, the desired PCI device is located in the
 328  * list of PCI devices.
 329  *
 330  * If the device is found, its reference count is increased and this
 331  * function returns a pointer to its data structure.  The caller must
 332  * decrement the reference count by calling pci_dev_put().
 333  * If no device is found, %NULL is returned.
 334  */
 335 struct pci_dev *acpi_get_pci_dev(acpi_handle handle)
 336 {
 337         int dev, fn;
 338         unsigned long long adr;
 339         acpi_status status;
 340         acpi_handle phandle;
 341         struct pci_bus *pbus;
 342         struct pci_dev *pdev = NULL;
 343         struct acpi_handle_node *node, *tmp;
 344         struct acpi_pci_root *root;
 345         LIST_HEAD(device_list);
 346
 347         /*
 348          * Walk up the ACPI CA namespace until we reach a PCI root bridge.
 349          */
 350         phandle = handle;
 351         while (!acpi_is_root_bridge(phandle)) {
 352                 node = kzalloc(sizeof(struct acpi_handle_node), GFP_KERNEL);
 353                 if (!node)
 354                         goto out;
 355
 356                 INIT_LIST_HEAD(&node->node);
 357                 node->handle = phandle;
 358                 list_add(&node->node, &device_list);
 359
 360                 status = acpi_get_parent(phandle, &phandle);
 361                 if (ACPI_FAILURE(status))
 362                         goto out;
 363         }
 364
 365         root = acpi_pci_find_root(phandle);
 366         if (!root)
 367                 goto out;
 368
 369         pbus = root->bus;
 370
 371         /*
 372          * Now, walk back down the PCI device tree until we return to our
 373          * original handle. Assumes that everything between the PCI root
 374          * bridge and the device we're looking for must be a P2P bridge.
 375          */
 376         list_for_each_entry(node, &device_list, node) {
 377                 acpi_handle hnd = node->handle;
 378                 status = acpi_evaluate_integer(hnd, "_ADR", NULL, &adr);
 379                 if (ACPI_FAILURE(status))
 380                         goto out;
 381                 dev = (adr >> 16) & 0xffff;
 382                 fn  = adr & 0xffff;
 383
 384                 pdev = pci_get_slot(pbus, PCI_DEVFN(dev, fn));
 385                 if (!pdev || hnd == handle)
 386                         break;
 387
 388                 pbus = pdev->subordinate;
 389                 pci_dev_put(pdev);
 390         }
 391 out:
 392         list_for_each_entry_safe(node, tmp, &device_list, node)
 393                 kfree(node);
 394
 395         return pdev;
 396 }
 397 EXPORT_SYMBOL_GPL(acpi_get_pci_dev);
 398
 399 /**
 400  * acpi_pci_osc_control_set - commit requested control to Firmware
 401  * @handle: acpi_handle for the target ACPI object
 402  * @flags: driver's requested control bits
 403  *
 404  * Attempt to take control from Firmware on requested control bits.
 405  **/
 406 acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 flags)
 407 {
 408         acpi_status status;
 409         u32 control_req, result, capbuf[3];
 410         acpi_handle tmp;
 411         struct acpi_pci_root *root;
 412
 413         status = acpi_get_handle(handle, "_OSC", &tmp);
 414         if (ACPI_FAILURE(status))
 415                 return status;
 416
 417         control_req = (flags & OSC_CONTROL_MASKS);
 418         if (!control_req)
 419                 return AE_TYPE;
 420
 421         root = acpi_pci_find_root(handle);
 422         if (!root)
 423                 return AE_NOT_EXIST;
 424
 425         mutex_lock(&osc_lock);
 426         /* No need to evaluate _OSC if the control was already granted. */
 427         if ((root->osc_control_set & control_req) == control_req)
 428                 goto out;
 429
 430         /* Need to query controls first before requesting them */
 431         if (!root->osc_queried) {
 432                 status = acpi_pci_query_osc(root, root->osc_support_set);
 433                 if (ACPI_FAILURE(status))
 434                         goto out;
 435         }
 436         if ((root->osc_control_qry & control_req) != control_req) {
 437                 printk(KERN_DEBUG
 438                        "Firmware did not grant requested _OSC control\n");
 439                 status = AE_SUPPORT;
 440                 goto out;
 441         }
 442
 443         capbuf[OSC_QUERY_TYPE] = 0;
 444         capbuf[OSC_SUPPORT_TYPE] = root->osc_support_set;
 445         capbuf[OSC_CONTROL_TYPE] = root->osc_control_set | control_req;
 446         status = acpi_pci_run_osc(handle, capbuf, &result);
 447         if (ACPI_SUCCESS(status))
 448                 root->osc_control_set = result;
 449 out:
 450         mutex_unlock(&osc_lock);
 451         return status;
 452 }
 453 EXPORT_SYMBOL(acpi_pci_osc_control_set);
 454
 455 static int __devinit acpi_pci_root_add(struct acpi_device *device)
 456 {
 457         unsigned long long segment, bus;
 458         acpi_status status;
 459         int result;
 460         struct acpi_pci_root *root;
 461         acpi_handle handle;
 462         struct acpi_device *child;
 463         u32 flags, base_flags;
 464
 465         segment = 0;
 466         status = acpi_evaluate_integer(device->handle, METHOD_NAME__SEG, NULL,
 467                                        &segment);
 468         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 469                 printk(KERN_ERR PREFIX "can't evaluate _SEG\n");
 470                 return -ENODEV;
 471         }
 472
 473         /* Check _CRS first, then _BBN.  If no _BBN, default to zero. */
 474         bus = 0;
 475         status = try_get_root_bridge_busnr(device->handle, &bus);
 476         if (ACPI_FAILURE(status)) {
 477                 status = acpi_evaluate_integer(device->handle, METHOD_NAME__BBN,                                               NULL, &bus);
 478                 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 479                         printk(KERN_ERR PREFIX
 480                              "no bus number in _CRS and can't evaluate _BBN\n");
 481                         return -ENODEV;
 482                 }
 483         }
 484
 485         root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
 486         if (!root)
 487                 return -ENOMEM;
 488
 489         INIT_LIST_HEAD(&root->node);
 490         root->device = device;
 491         root->segment = segment & 0xFFFF;
 492         root->bus_nr = bus & 0xFF;
 493         strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
 494         strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
 495         device->driver_data = root;
 496
 497         /*
 498          * All supported architectures that use ACPI have support for
 499          * PCI domains, so we indicate this in _OSC support capabilities.
 500          */
 501         flags = base_flags = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
 502         acpi_pci_osc_support(root, flags);
 503
 504         /*
 505          * TBD: Need PCI interface for enumeration/configuration of roots.
 506          */
 507
 508         /* TBD: Locking */
 509         list_add_tail(&root->node, &acpi_pci_roots);
 510
 511         printk(KERN_INFO PREFIX "%s [%s] (%04x:%02x)\n",
 512                acpi_device_name(device), acpi_device_bid(device),
 513                root->segment, root->bus_nr);
 514
 515         /*
 516          * Scan the Root Bridge
 517          * --------------------
 518          * Must do this prior to any attempt to bind the root device, as the
 519          * PCI namespace does not get created until this call is made (and
 520          * thus the root bridge's pci_dev does not exist).
 521          */
 522         root->bus = pci_acpi_scan_root(device, segment, bus);
 523         if (!root->bus) {
 524                 printk(KERN_ERR PREFIX
 525                             "Bus %04x:%02x not present in PCI namespace\n",
 526                             root->segment, root->bus_nr);
 527                 result = -ENODEV;
 528                 goto end;
 529         }
 530
 531         /*
 532          * Attach ACPI-PCI Context
 533          * -----------------------
 534          * Thus binding the ACPI and PCI devices.
 535          */
 536         result = acpi_pci_bind_root(device);
 537         if (result)
 538                 goto end;
 539
 540         /*
 541          * PCI Routing Table
 542          * -----------------
 543          * Evaluate and parse _PRT, if exists.
 544          */
 545         status = acpi_get_handle(device->handle, METHOD_NAME__PRT, &handle);
 546         if (ACPI_SUCCESS(status))
 547                 result = acpi_pci_irq_add_prt(device->handle, root->bus);
 548
 549         /*
 550          * Scan and bind all _ADR-Based Devices
 551          */
 552         list_for_each_entry(child, &device->children, node)
 553                 acpi_pci_bridge_scan(child);
 554
 555         /* Indicate support for various _OSC capabilities. */
 556         if (pci_ext_cfg_avail(root->bus->self))
 557                 flags |= OSC_EXT_PCI_CONFIG_SUPPORT;
 558         if (pcie_aspm_enabled())
 559                 flags |= OSC_ACTIVE_STATE_PWR_SUPPORT |
 560                         OSC_CLOCK_PWR_CAPABILITY_SUPPORT;
 561         if (pci_msi_enabled())
 562                 flags |= OSC_MSI_SUPPORT;
 563         if (flags != base_flags)
 564                 acpi_pci_osc_support(root, flags);
 565
 566         return 0;
 567
 568 end:
 569         if (!list_empty(&root->node))
 570                 list_del(&root->node);
 571         kfree(root);
 572         return result;
 573 }
 574
 575 static int acpi_pci_root_start(struct acpi_device *device)
 576 {
 577         struct acpi_pci_root *root = acpi_driver_data(device);
 578
 579         pci_bus_add_devices(root->bus);
 580         return 0;
 581 }
 582
 583 static int acpi_pci_root_remove(struct acpi_device *device, int type)
 584 {
 585         struct acpi_pci_root *root = acpi_driver_data(device);
 586
 587         kfree(root);
 588         return 0;
 589 }
 590
 591 static int __init acpi_pci_root_init(void)
 592 {
 593         if (acpi_pci_disabled)
 594                 return 0;
 595
 596         if (acpi_bus_register_driver(&acpi_pci_root_driver) < 0)
 597                 return -ENODEV;
 598
 599         return 0;
 600 }
 601
 602 subsys_initcall(acpi_pci_root_init);