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 struct acpi_pci_root {
  65         struct list_head node;
  66         struct acpi_device *device;
  67         struct pci_bus *bus;
  68         u16 segment;
  69         u8 bus_nr;
  70
  71         u32 osc_support_set;    /* _OSC state of support bits */
  72         u32 osc_control_set;    /* _OSC state of control bits */
  73         u32 osc_control_qry;    /* the latest _OSC query result */
  74
  75         u32 osc_queried:1;      /* has _OSC control been queried? */
  76 };
  77
  78 static LIST_HEAD(acpi_pci_roots);
  79
  80 static struct acpi_pci_driver *sub_driver;
  81 static DEFINE_MUTEX(osc_lock);
  82
  83 int acpi_pci_register_driver(struct acpi_pci_driver *driver)
  84 {
  85         int n = 0;
  86         struct acpi_pci_root *root;
  87
  88         struct acpi_pci_driver **pptr = &sub_driver;
  89         while (*pptr)
  90                 pptr = &(*pptr)->next;
  91         *pptr = driver;
  92
  93         if (!driver->add)
  94                 return 0;
  95
  96         list_for_each_entry(root, &acpi_pci_roots, node) {
  97                 driver->add(root->device->handle);
  98                 n++;
  99         }
 100
 101         return n;
 102 }
 103
 104 EXPORT_SYMBOL(acpi_pci_register_driver);
 105
 106 void acpi_pci_unregister_driver(struct acpi_pci_driver *driver)
 107 {
 108         struct acpi_pci_root *root;
 109
 110         struct acpi_pci_driver **pptr = &sub_driver;
 111         while (*pptr) {
 112                 if (*pptr == driver)
 113                         break;
 114                 pptr = &(*pptr)->next;
 115         }
 116         BUG_ON(!*pptr);
 117         *pptr = (*pptr)->next;
 118
 119         if (!driver->remove)
 120                 return;
 121
 122         list_for_each_entry(root, &acpi_pci_roots, node)
 123                 driver->remove(root->device->handle);
 124 }
 125
 126 EXPORT_SYMBOL(acpi_pci_unregister_driver);
 127
 128 acpi_handle acpi_get_pci_rootbridge_handle(unsigned int seg, unsigned int bus)
 129 {
 130         struct acpi_pci_root *root;
 131
 132         list_for_each_entry(root, &acpi_pci_roots, node)
 133                 if ((root->segment == (u16) seg) && (root->bus_nr == (u16) bus))
 134                         return root->device->handle;
 135         return NULL;
 136 }
 137
 138 EXPORT_SYMBOL_GPL(acpi_get_pci_rootbridge_handle);
 139
 140 /**
 141  * acpi_is_root_bridge - determine whether an ACPI CA node is a PCI root bridge
 142  * @handle - the ACPI CA node in question.
 143  *
 144  * Note: we could make this API take a struct acpi_device * instead, but
 145  * for now, it's more convenient to operate on an acpi_handle.
 146  */
 147 int acpi_is_root_bridge(acpi_handle handle)
 148 {
 149         int ret;
 150         struct acpi_device *device;
 151
 152         ret = acpi_bus_get_device(handle, &device);
 153         if (ret)
 154                 return 0;
 155
 156         ret = acpi_match_device_ids(device, root_device_ids);
 157         if (ret)
 158                 return 0;
 159         else
 160                 return 1;
 161 }
 162 EXPORT_SYMBOL_GPL(acpi_is_root_bridge);
 163
 164 static acpi_status
 165 get_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
 166 {
 167         int *busnr = data;
 168         struct acpi_resource_address64 address;
 169
 170         if (resource->type != ACPI_RESOURCE_TYPE_ADDRESS16 &&
 171             resource->type != ACPI_RESOURCE_TYPE_ADDRESS32 &&
 172             resource->type != ACPI_RESOURCE_TYPE_ADDRESS64)
 173                 return AE_OK;
 174
 175         acpi_resource_to_address64(resource, &address);
 176         if ((address.address_length > 0) &&
 177             (address.resource_type == ACPI_BUS_NUMBER_RANGE))
 178                 *busnr = address.minimum;
 179
 180         return AE_OK;
 181 }
 182
 183 static acpi_status try_get_root_bridge_busnr(acpi_handle handle,
 184                                              unsigned long long *bus)
 185 {
 186         acpi_status status;
 187         int busnum;
 188
 189         busnum = -1;
 190         status =
 191             acpi_walk_resources(handle, METHOD_NAME__CRS,
 192                                 get_root_bridge_busnr_callback, &busnum);
 193         if (ACPI_FAILURE(status))
 194                 return status;
 195         /* Check if we really get a bus number from _CRS */
 196         if (busnum == -1)
 197                 return AE_ERROR;
 198         *bus = busnum;
 199         return AE_OK;
 200 }
 201
 202 static void acpi_pci_bridge_scan(struct acpi_device *device)
 203 {
 204         int status;
 205         struct acpi_device *child = NULL;
 206
 207         if (device->flags.bus_address)
 208                 if (device->parent && device->parent->ops.bind) {
 209                         status = device->parent->ops.bind(device);
 210                         if (!status) {
 211                                 list_for_each_entry(child, &device->children, node)
 212                                         acpi_pci_bridge_scan(child);
 213                         }
 214                 }
 215 }
 216
 217 static u8 OSC_UUID[16] = {0x5B, 0x4D, 0xDB, 0x33, 0xF7, 0x1F, 0x1C, 0x40,
 218                           0x96, 0x57, 0x74, 0x41, 0xC0, 0x3D, 0xD7, 0x66};
 219
 220 static acpi_status acpi_pci_run_osc(acpi_handle handle,
 221                                     const u32 *capbuf, u32 *retval)
 222 {
 223         acpi_status status;
 224         struct acpi_object_list input;
 225         union acpi_object in_params[4];
 226         struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL};
 227         union acpi_object *out_obj;
 228         u32 errors;
 229
 230         /* Setting up input parameters */
 231         input.count = 4;
 232         input.pointer = in_params;
 233         in_params[0].type               = ACPI_TYPE_BUFFER;
 234         in_params[0].buffer.length      = 16;
 235         in_params[0].buffer.pointer     = OSC_UUID;
 236         in_params[1].type               = ACPI_TYPE_INTEGER;
 237         in_params[1].integer.value      = 1;
 238         in_params[2].type               = ACPI_TYPE_INTEGER;
 239         in_params[2].integer.value      = 3;
 240         in_params[3].type               = ACPI_TYPE_BUFFER;
 241         in_params[3].buffer.length      = 12;
 242         in_params[3].buffer.pointer     = (u8 *)capbuf;
 243
 244         status = acpi_evaluate_object(handle, "_OSC", &input, &output);
 245         if (ACPI_FAILURE(status))
 246                 return status;
 247
 248         if (!output.length)
 249                 return AE_NULL_OBJECT;
 250
 251         out_obj = output.pointer;
 252         if (out_obj->type != ACPI_TYPE_BUFFER) {
 253                 printk(KERN_DEBUG "_OSC evaluation returned wrong type\n");
 254                 status = AE_TYPE;
 255                 goto out_kfree;
 256         }
 257         /* Need to ignore the bit0 in result code */
 258         errors = *((u32 *)out_obj->buffer.pointer) & ~(1 << 0);
 259         if (errors) {
 260                 if (errors & OSC_REQUEST_ERROR)
 261                         printk(KERN_DEBUG "_OSC request failed\n");
 262                 if (errors & OSC_INVALID_UUID_ERROR)
 263                         printk(KERN_DEBUG "_OSC invalid UUID\n");
 264                 if (errors & OSC_INVALID_REVISION_ERROR)
 265                         printk(KERN_DEBUG "_OSC invalid revision\n");
 266                 if (errors & OSC_CAPABILITIES_MASK_ERROR) {
 267                         if (capbuf[OSC_QUERY_TYPE] & OSC_QUERY_ENABLE)
 268                                 goto out_success;
 269                         printk(KERN_DEBUG
 270                                "Firmware did not grant requested _OSC control\n");
 271                         status = AE_SUPPORT;
 272                         goto out_kfree;
 273                 }
 274                 status = AE_ERROR;
 275                 goto out_kfree;
 276         }
 277 out_success:
 278         *retval = *((u32 *)(out_obj->buffer.pointer + 8));
 279         status = AE_OK;
 280
 281 out_kfree:
 282         kfree(output.pointer);
 283         return status;
 284 }
 285
 286 static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root, u32 flags)
 287 {
 288         acpi_status status;
 289         u32 support_set, result, capbuf[3];
 290
 291         /* do _OSC query for all possible controls */
 292         support_set = root->osc_support_set | (flags & OSC_SUPPORT_MASKS);
 293         capbuf[OSC_QUERY_TYPE] = OSC_QUERY_ENABLE;
 294         capbuf[OSC_SUPPORT_TYPE] = support_set;
 295         capbuf[OSC_CONTROL_TYPE] = OSC_CONTROL_MASKS;
 296
 297         status = acpi_pci_run_osc(root->device->handle, capbuf, &result);
 298         if (ACPI_SUCCESS(status)) {
 299                 root->osc_support_set = support_set;
 300                 root->osc_control_qry = result;
 301                 root->osc_queried = 1;
 302         }
 303         return status;
 304 }
 305
 306 static acpi_status acpi_pci_osc_support(struct acpi_pci_root *root, u32 flags)
 307 {
 308         acpi_status status;
 309         acpi_handle tmp;
 310
 311         status = acpi_get_handle(root->device->handle, "_OSC", &tmp);
 312         if (ACPI_FAILURE(status))
 313                 return status;
 314         mutex_lock(&osc_lock);
 315         status = acpi_pci_query_osc(root, flags);
 316         mutex_unlock(&osc_lock);
 317         return status;
 318 }
 319
 320 static struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle)
 321 {
 322         struct acpi_pci_root *root;
 323
 324         list_for_each_entry(root, &acpi_pci_roots, node) {
 325                 if (root->device->handle == handle)
 326                         return root;
 327         }
 328         return NULL;
 329 }
 330
 331 struct acpi_handle_node {
 332         struct list_head node;
 333         acpi_handle handle;
 334 };
 335
 336 /**
 337  * acpi_get_pci_dev - convert ACPI CA handle to struct pci_dev
 338  * @handle: the handle in question
 339  *
 340  * Given an ACPI CA handle, the desired PCI device is located in the
 341  * list of PCI devices.
 342  *
 343  * If the device is found, its reference count is increased and this
 344  * function returns a pointer to its data structure.  The caller must
 345  * decrement the reference count by calling pci_dev_put().
 346  * If no device is found, %NULL is returned.
 347  */
 348 struct pci_dev *acpi_get_pci_dev(acpi_handle handle)
 349 {
 350         int dev, fn;
 351         unsigned long long adr;
 352         acpi_status status;
 353         acpi_handle phandle;
 354         struct pci_bus *pbus;
 355         struct pci_dev *pdev = NULL;
 356         struct acpi_handle_node *node, *tmp;
 357         struct acpi_pci_root *root;
 358         LIST_HEAD(device_list);
 359
 360         /*
 361          * Walk up the ACPI CA namespace until we reach a PCI root bridge.
 362          */
 363         phandle = handle;
 364         while (!acpi_is_root_bridge(phandle)) {
 365                 node = kzalloc(sizeof(struct acpi_handle_node), GFP_KERNEL);
 366                 if (!node)
 367                         goto out;
 368
 369                 INIT_LIST_HEAD(&node->node);
 370                 node->handle = phandle;
 371                 list_add(&node->node, &device_list);
 372
 373                 status = acpi_get_parent(phandle, &phandle);
 374                 if (ACPI_FAILURE(status))
 375                         goto out;
 376         }
 377
 378         root = acpi_pci_find_root(phandle);
 379         if (!root)
 380                 goto out;
 381
 382         pbus = root->bus;
 383
 384         /*
 385          * Now, walk back down the PCI device tree until we return to our
 386          * original handle. Assumes that everything between the PCI root
 387          * bridge and the device we're looking for must be a P2P bridge.
 388          */
 389         list_for_each_entry(node, &device_list, node) {
 390                 acpi_handle hnd = node->handle;
 391                 status = acpi_evaluate_integer(hnd, "_ADR", NULL, &adr);
 392                 if (ACPI_FAILURE(status))
 393                         goto out;
 394                 dev = (adr >> 16) & 0xffff;
 395                 fn  = adr & 0xffff;
 396
 397                 pdev = pci_get_slot(pbus, PCI_DEVFN(dev, fn));
 398                 if (!pdev || hnd == handle)
 399                         break;
 400
 401                 pbus = pdev->subordinate;
 402                 pci_dev_put(pdev);
 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);