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 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 OSC_UUID[16] = {0x5B, 0x4D, 0xDB, 0x33, 0xF7, 0x1F, 0x1C, 0x40,
 206                           0x96, 0x57, 0x74, 0x41, 0xC0, 0x3D, 0xD7, 0x66};
 207
 208 static acpi_status acpi_pci_run_osc(acpi_handle handle,
 209                                     const u32 *capbuf, u32 *retval)
 210 {
 211         acpi_status status;
 212         struct acpi_object_list input;
 213         union acpi_object in_params[4];
 214         struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL};
 215         union acpi_object *out_obj;
 216         u32 errors;
 217
 218         /* Setting up input parameters */
 219         input.count = 4;
 220         input.pointer = in_params;
 221         in_params[0].type               = ACPI_TYPE_BUFFER;
 222         in_params[0].buffer.length      = 16;
 223         in_params[0].buffer.pointer     = OSC_UUID;
 224         in_params[1].type               = ACPI_TYPE_INTEGER;
 225         in_params[1].integer.value      = 1;
 226         in_params[2].type               = ACPI_TYPE_INTEGER;
 227         in_params[2].integer.value      = 3;
 228         in_params[3].type               = ACPI_TYPE_BUFFER;
 229         in_params[3].buffer.length      = 12;
 230         in_params[3].buffer.pointer     = (u8 *)capbuf;
 231
 232         status = acpi_evaluate_object(handle, "_OSC", &input, &output);
 233         if (ACPI_FAILURE(status))
 234                 return status;
 235
 236         if (!output.length)
 237                 return AE_NULL_OBJECT;
 238
 239         out_obj = output.pointer;
 240         if (out_obj->type != ACPI_TYPE_BUFFER) {
 241                 printk(KERN_DEBUG "_OSC evaluation returned wrong type\n");
 242                 status = AE_TYPE;
 243                 goto out_kfree;
 244         }
 245         /* Need to ignore the bit0 in result code */
 246         errors = *((u32 *)out_obj->buffer.pointer) & ~(1 << 0);
 247         if (errors) {
 248                 if (errors & OSC_REQUEST_ERROR)
 249                         printk(KERN_DEBUG "_OSC request failed\n");
 250                 if (errors & OSC_INVALID_UUID_ERROR)
 251                         printk(KERN_DEBUG "_OSC invalid UUID\n");
 252                 if (errors & OSC_INVALID_REVISION_ERROR)
 253                         printk(KERN_DEBUG "_OSC invalid revision\n");
 254                 if (errors & OSC_CAPABILITIES_MASK_ERROR) {
 255                         if (capbuf[OSC_QUERY_TYPE] & OSC_QUERY_ENABLE)
 256                                 goto out_success;
 257                         printk(KERN_DEBUG
 258                                "Firmware did not grant requested _OSC control\n");
 259                         status = AE_SUPPORT;
 260                         goto out_kfree;
 261                 }
 262                 status = AE_ERROR;
 263                 goto out_kfree;
 264         }
 265 out_success:
 266         *retval = *((u32 *)(out_obj->buffer.pointer + 8));
 267         status = AE_OK;
 268
 269 out_kfree:
 270         kfree(output.pointer);
 271         return status;
 272 }
 273
 274 static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root, u32 flags)
 275 {
 276         acpi_status status;
 277         u32 support_set, result, capbuf[3];
 278
 279         /* do _OSC query for all possible controls */
 280         support_set = root->osc_support_set | (flags & OSC_SUPPORT_MASKS);
 281         capbuf[OSC_QUERY_TYPE] = OSC_QUERY_ENABLE;
 282         capbuf[OSC_SUPPORT_TYPE] = support_set;
 283         capbuf[OSC_CONTROL_TYPE] = OSC_CONTROL_MASKS;
 284
 285         status = acpi_pci_run_osc(root->device->handle, capbuf, &result);
 286         if (ACPI_SUCCESS(status)) {
 287                 root->osc_support_set = support_set;
 288                 root->osc_control_qry = result;
 289                 root->osc_queried = 1;
 290         }
 291         return status;
 292 }
 293
 294 static acpi_status acpi_pci_osc_support(struct acpi_pci_root *root, u32 flags)
 295 {
 296         acpi_status status;
 297         acpi_handle tmp;
 298
 299         status = acpi_get_handle(root->device->handle, "_OSC", &tmp);
 300         if (ACPI_FAILURE(status))
 301                 return status;
 302         mutex_lock(&osc_lock);
 303         status = acpi_pci_query_osc(root, flags);
 304         mutex_unlock(&osc_lock);
 305         return status;
 306 }
 307
 308 struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle)
 309 {
 310         struct acpi_pci_root *root;
 311
 312         list_for_each_entry(root, &acpi_pci_roots, node) {
 313                 if (root->device->handle == handle)
 314                         return root;
 315         }
 316         return NULL;
 317 }
 318 EXPORT_SYMBOL_GPL(acpi_pci_find_root);
 319
 320 struct acpi_handle_node {
 321         struct list_head node;
 322         acpi_handle handle;
 323 };
 324
 325 /**
 326  * acpi_get_pci_dev - convert ACPI CA handle to struct pci_dev
 327  * @handle: the handle in question
 328  *
 329  * Given an ACPI CA handle, the desired PCI device is located in the
 330  * list of PCI devices.
 331  *
 332  * If the device is found, its reference count is increased and this
 333  * function returns a pointer to its data structure.  The caller must
 334  * decrement the reference count by calling pci_dev_put().
 335  * If no device is found, %NULL is returned.
 336  */
 337 struct pci_dev *acpi_get_pci_dev(acpi_handle handle)
 338 {
 339         int dev, fn;
 340         unsigned long long adr;
 341         acpi_status status;
 342         acpi_handle phandle;
 343         struct pci_bus *pbus;
 344         struct pci_dev *pdev = NULL;
 345         struct acpi_handle_node *node, *tmp;
 346         struct acpi_pci_root *root;
 347         LIST_HEAD(device_list);
 348
 349         /*
 350          * Walk up the ACPI CA namespace until we reach a PCI root bridge.
 351          */
 352         phandle = handle;
 353         while (!acpi_is_root_bridge(phandle)) {
 354                 node = kzalloc(sizeof(struct acpi_handle_node), GFP_KERNEL);
 355                 if (!node)
 356                         goto out;
 357
 358                 INIT_LIST_HEAD(&node->node);
 359                 node->handle = phandle;
 360                 list_add(&node->node, &device_list);
 361
 362                 status = acpi_get_parent(phandle, &phandle);
 363                 if (ACPI_FAILURE(status))
 364                         goto out;
 365         }
 366
 367         root = acpi_pci_find_root(phandle);
 368         if (!root)
 369                 goto out;
 370
 371         pbus = root->bus;
 372
 373         /*
 374          * Now, walk back down the PCI device tree until we return to our
 375          * original handle. Assumes that everything between the PCI root
 376          * bridge and the device we're looking for must be a P2P bridge.
 377          */
 378         list_for_each_entry(node, &device_list, node) {
 379                 acpi_handle hnd = node->handle;
 380                 status = acpi_evaluate_integer(hnd, "_ADR", NULL, &adr);
 381                 if (ACPI_FAILURE(status))
 382                         goto out;
 383                 dev = (adr >> 16) & 0xffff;
 384                 fn  = adr & 0xffff;
 385
 386                 pdev = pci_get_slot(pbus, PCI_DEVFN(dev, fn));
 387                 if (!pdev || hnd == handle)
 388                         break;
 389
 390                 pbus = pdev->subordinate;
 391                 pci_dev_put(pdev);
 392
 393                 /*
 394                  * This function may be called for a non-PCI device that has a
 395                  * PCI parent (eg. a disk under a PCI SATA controller).  In that
 396                  * case pdev->subordinate will be NULL for the parent.
 397                  */
 398                 if (!pbus) {
 399                         dev_dbg(&pdev->dev, "Not a PCI-to-PCI bridge\n");
 400                         pdev = NULL;
 401                         break;
 402                 }
 403         }
 404 out:
 405         list_for_each_entry_safe(node, tmp, &device_list, node)
 406                 kfree(node);
 407
 408         return pdev;
 409 }
 410 EXPORT_SYMBOL_GPL(acpi_get_pci_dev);
 411
 412 /**
 413  * acpi_pci_osc_control_set - commit requested control to Firmware
 414  * @handle: acpi_handle for the target ACPI object
 415  * @flags: driver's requested control bits
 416  *
 417  * Attempt to take control from Firmware on requested control bits.
 418  **/
 419 acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 flags)
 420 {
 421         acpi_status status;
 422         u32 control_req, result, capbuf[3];
 423         acpi_handle tmp;
 424         struct acpi_pci_root *root;
 425
 426         status = acpi_get_handle(handle, "_OSC", &tmp);
 427         if (ACPI_FAILURE(status))
 428                 return status;
 429
 430         control_req = (flags & OSC_CONTROL_MASKS);
 431         if (!control_req)
 432                 return AE_TYPE;
 433
 434         root = acpi_pci_find_root(handle);
 435         if (!root)
 436                 return AE_NOT_EXIST;
 437
 438         mutex_lock(&osc_lock);
 439         /* No need to evaluate _OSC if the control was already granted. */
 440         if ((root->osc_control_set & control_req) == control_req)
 441                 goto out;
 442
 443         /* Need to query controls first before requesting them */
 444         if (!root->osc_queried) {
 445                 status = acpi_pci_query_osc(root, root->osc_support_set);
 446                 if (ACPI_FAILURE(status))
 447                         goto out;
 448         }
 449         if ((root->osc_control_qry & control_req) != control_req) {
 450                 printk(KERN_DEBUG
 451                        "Firmware did not grant requested _OSC control\n");
 452                 status = AE_SUPPORT;
 453                 goto out;
 454         }
 455
 456         capbuf[OSC_QUERY_TYPE] = 0;
 457         capbuf[OSC_SUPPORT_TYPE] = root->osc_support_set;
 458         capbuf[OSC_CONTROL_TYPE] = root->osc_control_set | control_req;
 459         status = acpi_pci_run_osc(handle, capbuf, &result);
 460         if (ACPI_SUCCESS(status))
 461                 root->osc_control_set = result;
 462 out:
 463         mutex_unlock(&osc_lock);
 464         return status;
 465 }
 466 EXPORT_SYMBOL(acpi_pci_osc_control_set);
 467
 468 static int __devinit acpi_pci_root_add(struct acpi_device *device)
 469 {
 470         unsigned long long segment, bus;
 471         acpi_status status;
 472         int result;
 473         struct acpi_pci_root *root;
 474         acpi_handle handle;
 475         struct acpi_device *child;
 476         u32 flags, base_flags;
 477
 478         segment = 0;
 479         status = acpi_evaluate_integer(device->handle, METHOD_NAME__SEG, NULL,
 480                                        &segment);
 481         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 482                 printk(KERN_ERR PREFIX "can't evaluate _SEG\n");
 483                 return -ENODEV;
 484         }
 485
 486         /* Check _CRS first, then _BBN.  If no _BBN, default to zero. */
 487         bus = 0;
 488         status = try_get_root_bridge_busnr(device->handle, &bus);
 489         if (ACPI_FAILURE(status)) {
 490                 status = acpi_evaluate_integer(device->handle, METHOD_NAME__BBN,                                               NULL, &bus);
 491                 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 492                         printk(KERN_ERR PREFIX
 493                              "no bus number in _CRS and can't evaluate _BBN\n");
 494                         return -ENODEV;
 495                 }
 496         }
 497
 498         root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
 499         if (!root)
 500                 return -ENOMEM;
 501
 502         INIT_LIST_HEAD(&root->node);
 503         root->device = device;
 504         root->segment = segment & 0xFFFF;
 505         root->bus_nr = bus & 0xFF;
 506         strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
 507         strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
 508         device->driver_data = root;
 509
 510         /*
 511          * All supported architectures that use ACPI have support for
 512          * PCI domains, so we indicate this in _OSC support capabilities.
 513          */
 514         flags = base_flags = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
 515         acpi_pci_osc_support(root, flags);
 516
 517         /*
 518          * TBD: Need PCI interface for enumeration/configuration of roots.
 519          */
 520
 521         /* TBD: Locking */
 522         list_add_tail(&root->node, &acpi_pci_roots);
 523
 524         printk(KERN_INFO PREFIX "%s [%s] (%04x:%02x)\n",
 525                acpi_device_name(device), acpi_device_bid(device),
 526                root->segment, root->bus_nr);
 527
 528         /*
 529          * Scan the Root Bridge
 530          * --------------------
 531          * Must do this prior to any attempt to bind the root device, as the
 532          * PCI namespace does not get created until this call is made (and
 533          * thus the root bridge's pci_dev does not exist).
 534          */
 535         root->bus = pci_acpi_scan_root(device, segment, bus);
 536         if (!root->bus) {
 537                 printk(KERN_ERR PREFIX
 538                             "Bus %04x:%02x not present in PCI namespace\n",
 539                             root->segment, root->bus_nr);
 540                 result = -ENODEV;
 541                 goto end;
 542         }
 543
 544         /*
 545          * Attach ACPI-PCI Context
 546          * -----------------------
 547          * Thus binding the ACPI and PCI devices.
 548          */
 549         result = acpi_pci_bind_root(device);
 550         if (result)
 551                 goto end;
 552
 553         /*
 554          * PCI Routing Table
 555          * -----------------
 556          * Evaluate and parse _PRT, if exists.
 557          */
 558         status = acpi_get_handle(device->handle, METHOD_NAME__PRT, &handle);
 559         if (ACPI_SUCCESS(status))
 560                 result = acpi_pci_irq_add_prt(device->handle, root->bus);
 561
 562         /*
 563          * Scan and bind all _ADR-Based Devices
 564          */
 565         list_for_each_entry(child, &device->children, node)
 566                 acpi_pci_bridge_scan(child);
 567
 568         /* Indicate support for various _OSC capabilities. */
 569         if (pci_ext_cfg_avail(root->bus->self))
 570                 flags |= OSC_EXT_PCI_CONFIG_SUPPORT;
 571         if (pcie_aspm_enabled())
 572                 flags |= OSC_ACTIVE_STATE_PWR_SUPPORT |
 573                         OSC_CLOCK_PWR_CAPABILITY_SUPPORT;
 574         if (pci_msi_enabled())
 575                 flags |= OSC_MSI_SUPPORT;
 576         if (flags != base_flags)
 577                 acpi_pci_osc_support(root, flags);
 578
 579         return 0;
 580
 581 end:
 582         if (!list_empty(&root->node))
 583                 list_del(&root->node);
 584         kfree(root);
 585         return result;
 586 }
 587
 588 static int acpi_pci_root_start(struct acpi_device *device)
 589 {
 590         struct acpi_pci_root *root = acpi_driver_data(device);
 591
 592         pci_bus_add_devices(root->bus);
 593         return 0;
 594 }
 595
 596 static int acpi_pci_root_remove(struct acpi_device *device, int type)
 597 {
 598         struct acpi_pci_root *root = acpi_driver_data(device);
 599
 600         kfree(root);
 601         return 0;
 602 }
 603
 604 static int __init acpi_pci_root_init(void)
 605 {
 606         if (acpi_pci_disabled)
 607                 return 0;
 608
 609         if (acpi_bus_register_driver(&acpi_pci_root_driver) < 0)
 610                 return -ENODEV;
 611
 612         return 0;
 613 }
 614
 615 subsys_initcall(acpi_pci_root_init);