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/spinlock.h>
  31 #include <linux/pm.h>
  32 #include <linux/pm_runtime.h>
  33 #include <linux/pci.h>
  34 #include <linux/pci-acpi.h>
  35 #include <linux/acpi.h>
  36 #include <linux/slab.h>
  37 #include <acpi/acpi_bus.h>
  38 #include <acpi/acpi_drivers.h>
  39
  40 #define PREFIX "ACPI: "
  41
  42 #define _COMPONENT              ACPI_PCI_COMPONENT
  43 ACPI_MODULE_NAME("pci_root");
  44 #define ACPI_PCI_ROOT_CLASS             "pci_bridge"
  45 #define ACPI_PCI_ROOT_DEVICE_NAME       "PCI Root Bridge"
  46 static int acpi_pci_root_add(struct acpi_device *device);
  47 static int acpi_pci_root_remove(struct acpi_device *device, int type);
  48 static int acpi_pci_root_start(struct acpi_device *device);
  49
  50 static const struct acpi_device_id root_device_ids[] = {
  51         {"PNP0A03", 0},
  52         {"", 0},
  53 };
  54 MODULE_DEVICE_TABLE(acpi, root_device_ids);
  55
  56 static struct acpi_driver acpi_pci_root_driver = {
  57         .name = "pci_root",
  58         .class = ACPI_PCI_ROOT_CLASS,
  59         .ids = root_device_ids,
  60         .ops = {
  61                 .add = acpi_pci_root_add,
  62                 .remove = acpi_pci_root_remove,
  63                 .start = acpi_pci_root_start,
  64                 },
  65 };
  66
  67 static LIST_HEAD(acpi_pci_roots);
  68
  69 static struct acpi_pci_driver *sub_driver;
  70 static DEFINE_MUTEX(osc_lock);
  71
  72 int acpi_pci_register_driver(struct acpi_pci_driver *driver)
  73 {
  74         int n = 0;
  75         struct acpi_pci_root *root;
  76
  77         struct acpi_pci_driver **pptr = &sub_driver;
  78         while (*pptr)
  79                 pptr = &(*pptr)->next;
  80         *pptr = driver;
  81
  82         if (!driver->add)
  83                 return 0;
  84
  85         list_for_each_entry(root, &acpi_pci_roots, node) {
  86                 driver->add(root->device->handle);
  87                 n++;
  88         }
  89
  90         return n;
  91 }
  92
  93 EXPORT_SYMBOL(acpi_pci_register_driver);
  94
  95 void acpi_pci_unregister_driver(struct acpi_pci_driver *driver)
  96 {
  97         struct acpi_pci_root *root;
  98
  99         struct acpi_pci_driver **pptr = &sub_driver;
 100         while (*pptr) {
 101                 if (*pptr == driver)
 102                         break;
 103                 pptr = &(*pptr)->next;
 104         }
 105         BUG_ON(!*pptr);
 106         *pptr = (*pptr)->next;
 107
 108         if (!driver->remove)
 109                 return;
 110
 111         list_for_each_entry(root, &acpi_pci_roots, node)
 112                 driver->remove(root->device->handle);
 113 }
 114
 115 EXPORT_SYMBOL(acpi_pci_unregister_driver);
 116
 117 acpi_handle acpi_get_pci_rootbridge_handle(unsigned int seg, unsigned int bus)
 118 {
 119         struct acpi_pci_root *root;
 120
 121         list_for_each_entry(root, &acpi_pci_roots, node)
 122                 if ((root->segment == (u16) seg) &&
 123                     (root->secondary.start == (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         struct resource *res = 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                 res->start = address.minimum;
 169                 res->end = address.minimum + address.address_length - 1;
 170         }
 171
 172         return AE_OK;
 173 }
 174
 175 static acpi_status try_get_root_bridge_busnr(acpi_handle handle,
 176                                              struct resource *res)
 177 {
 178         acpi_status status;
 179
 180         res->start = -1;
 181         status =
 182             acpi_walk_resources(handle, METHOD_NAME__CRS,
 183                                 get_root_bridge_busnr_callback, res);
 184         if (ACPI_FAILURE(status))
 185                 return status;
 186         if (res->start == -1)
 187                 return AE_ERROR;
 188         return AE_OK;
 189 }
 190
 191 static void acpi_pci_bridge_scan(struct acpi_device *device)
 192 {
 193         int status;
 194         struct acpi_device *child = NULL;
 195
 196         if (device->flags.bus_address)
 197                 if (device->parent && device->parent->ops.bind) {
 198                         status = device->parent->ops.bind(device);
 199                         if (!status) {
 200                                 list_for_each_entry(child, &device->children, node)
 201                                         acpi_pci_bridge_scan(child);
 202                         }
 203                 }
 204 }
 205
 206 static u8 pci_osc_uuid_str[] = "33DB4D5B-1FF7-401C-9657-7441C03DD766";
 207
 208 static acpi_status acpi_pci_run_osc(acpi_handle handle,
 209                                     const u32 *capbuf, u32 *retval)
 210 {
 211         struct acpi_osc_context context = {
 212                 .uuid_str = pci_osc_uuid_str,
 213                 .rev = 1,
 214                 .cap.length = 12,
 215                 .cap.pointer = (void *)capbuf,
 216         };
 217         acpi_status status;
 218
 219         status = acpi_run_osc(handle, &context);
 220         if (ACPI_SUCCESS(status)) {
 221                 *retval = *((u32 *)(context.ret.pointer + 8));
 222                 kfree(context.ret.pointer);
 223         }
 224         return status;
 225 }
 226
 227 static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root,
 228                                         u32 support,
 229                                         u32 *control)
 230 {
 231         acpi_status status;
 232         u32 result, capbuf[3];
 233
 234         support &= OSC_PCI_SUPPORT_MASKS;
 235         support |= root->osc_support_set;
 236
 237         capbuf[OSC_QUERY_TYPE] = OSC_QUERY_ENABLE;
 238         capbuf[OSC_SUPPORT_TYPE] = support;
 239         if (control) {
 240                 *control &= OSC_PCI_CONTROL_MASKS;
 241                 capbuf[OSC_CONTROL_TYPE] = *control | root->osc_control_set;
 242         } else {
 243                 /* Run _OSC query for all possible controls. */
 244                 capbuf[OSC_CONTROL_TYPE] = OSC_PCI_CONTROL_MASKS;
 245         }
 246
 247         status = acpi_pci_run_osc(root->device->handle, capbuf, &result);
 248         if (ACPI_SUCCESS(status)) {
 249                 root->osc_support_set = support;
 250                 if (control)
 251                         *control = result;
 252         }
 253         return status;
 254 }
 255
 256 static acpi_status acpi_pci_osc_support(struct acpi_pci_root *root, u32 flags)
 257 {
 258         acpi_status status;
 259         acpi_handle tmp;
 260
 261         status = acpi_get_handle(root->device->handle, "_OSC", &tmp);
 262         if (ACPI_FAILURE(status))
 263                 return status;
 264         mutex_lock(&osc_lock);
 265         status = acpi_pci_query_osc(root, flags, NULL);
 266         mutex_unlock(&osc_lock);
 267         return status;
 268 }
 269
 270 struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle)
 271 {
 272         struct acpi_pci_root *root;
 273
 274         list_for_each_entry(root, &acpi_pci_roots, node) {
 275                 if (root->device->handle == handle)
 276                         return root;
 277         }
 278         return NULL;
 279 }
 280 EXPORT_SYMBOL_GPL(acpi_pci_find_root);
 281
 282 struct acpi_handle_node {
 283         struct list_head node;
 284         acpi_handle handle;
 285 };
 286
 287 /**
 288  * acpi_get_pci_dev - convert ACPI CA handle to struct pci_dev
 289  * @handle: the handle in question
 290  *
 291  * Given an ACPI CA handle, the desired PCI device is located in the
 292  * list of PCI devices.
 293  *
 294  * If the device is found, its reference count is increased and this
 295  * function returns a pointer to its data structure.  The caller must
 296  * decrement the reference count by calling pci_dev_put().
 297  * If no device is found, %NULL is returned.
 298  */
 299 struct pci_dev *acpi_get_pci_dev(acpi_handle handle)
 300 {
 301         int dev, fn;
 302         unsigned long long adr;
 303         acpi_status status;
 304         acpi_handle phandle;
 305         struct pci_bus *pbus;
 306         struct pci_dev *pdev = NULL;
 307         struct acpi_handle_node *node, *tmp;
 308         struct acpi_pci_root *root;
 309         LIST_HEAD(device_list);
 310
 311         /*
 312          * Walk up the ACPI CA namespace until we reach a PCI root bridge.
 313          */
 314         phandle = handle;
 315         while (!acpi_is_root_bridge(phandle)) {
 316                 node = kzalloc(sizeof(struct acpi_handle_node), GFP_KERNEL);
 317                 if (!node)
 318                         goto out;
 319
 320                 INIT_LIST_HEAD(&node->node);
 321                 node->handle = phandle;
 322                 list_add(&node->node, &device_list);
 323
 324                 status = acpi_get_parent(phandle, &phandle);
 325                 if (ACPI_FAILURE(status))
 326                         goto out;
 327         }
 328
 329         root = acpi_pci_find_root(phandle);
 330         if (!root)
 331                 goto out;
 332
 333         pbus = root->bus;
 334
 335         /*
 336          * Now, walk back down the PCI device tree until we return to our
 337          * original handle. Assumes that everything between the PCI root
 338          * bridge and the device we're looking for must be a P2P bridge.
 339          */
 340         list_for_each_entry(node, &device_list, node) {
 341                 acpi_handle hnd = node->handle;
 342                 status = acpi_evaluate_integer(hnd, "_ADR", NULL, &adr);
 343                 if (ACPI_FAILURE(status))
 344                         goto out;
 345                 dev = (adr >> 16) & 0xffff;
 346                 fn  = adr & 0xffff;
 347
 348                 pdev = pci_get_slot(pbus, PCI_DEVFN(dev, fn));
 349                 if (!pdev || hnd == handle)
 350                         break;
 351
 352                 pbus = pdev->subordinate;
 353                 pci_dev_put(pdev);
 354
 355                 /*
 356                  * This function may be called for a non-PCI device that has a
 357                  * PCI parent (eg. a disk under a PCI SATA controller).  In that
 358                  * case pdev->subordinate will be NULL for the parent.
 359                  */
 360                 if (!pbus) {
 361                         dev_dbg(&pdev->dev, "Not a PCI-to-PCI bridge\n");
 362                         pdev = NULL;
 363                         break;
 364                 }
 365         }
 366 out:
 367         list_for_each_entry_safe(node, tmp, &device_list, node)
 368                 kfree(node);
 369
 370         return pdev;
 371 }
 372 EXPORT_SYMBOL_GPL(acpi_get_pci_dev);
 373
 374 /**
 375  * acpi_pci_osc_control_set - Request control of PCI root _OSC features.
 376  * @handle: ACPI handle of a PCI root bridge (or PCIe Root Complex).
 377  * @mask: Mask of _OSC bits to request control of, place to store control mask.
 378  * @req: Mask of _OSC bits the control of is essential to the caller.
 379  *
 380  * Run _OSC query for @mask and if that is successful, compare the returned
 381  * mask of control bits with @req.  If all of the @req bits are set in the
 382  * returned mask, run _OSC request for it.
 383  *
 384  * The variable at the @mask address may be modified regardless of whether or
 385  * not the function returns success.  On success it will contain the mask of
 386  * _OSC bits the BIOS has granted control of, but its contents are meaningless
 387  * on failure.
 388  **/
 389 acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 *mask, u32 req)
 390 {
 391         struct acpi_pci_root *root;
 392         acpi_status status;
 393         u32 ctrl, capbuf[3];
 394         acpi_handle tmp;
 395
 396         if (!mask)
 397                 return AE_BAD_PARAMETER;
 398
 399         ctrl = *mask & OSC_PCI_CONTROL_MASKS;
 400         if ((ctrl & req) != req)
 401                 return AE_TYPE;
 402
 403         root = acpi_pci_find_root(handle);
 404         if (!root)
 405                 return AE_NOT_EXIST;
 406
 407         status = acpi_get_handle(handle, "_OSC", &tmp);
 408         if (ACPI_FAILURE(status))
 409                 return status;
 410
 411         mutex_lock(&osc_lock);
 412
 413         *mask = ctrl | root->osc_control_set;
 414         /* No need to evaluate _OSC if the control was already granted. */
 415         if ((root->osc_control_set & ctrl) == ctrl)
 416                 goto out;
 417
 418         /* Need to check the available controls bits before requesting them. */
 419         while (*mask) {
 420                 status = acpi_pci_query_osc(root, root->osc_support_set, mask);
 421                 if (ACPI_FAILURE(status))
 422                         goto out;
 423                 if (ctrl == *mask)
 424                         break;
 425                 ctrl = *mask;
 426         }
 427
 428         if ((ctrl & req) != req) {
 429                 status = AE_SUPPORT;
 430                 goto out;
 431         }
 432
 433         capbuf[OSC_QUERY_TYPE] = 0;
 434         capbuf[OSC_SUPPORT_TYPE] = root->osc_support_set;
 435         capbuf[OSC_CONTROL_TYPE] = ctrl;
 436         status = acpi_pci_run_osc(handle, capbuf, mask);
 437         if (ACPI_SUCCESS(status))
 438                 root->osc_control_set = *mask;
 439 out:
 440         mutex_unlock(&osc_lock);
 441         return status;
 442 }
 443 EXPORT_SYMBOL(acpi_pci_osc_control_set);
 444
 445 static int __devinit acpi_pci_root_add(struct acpi_device *device)
 446 {
 447         unsigned long long segment, bus;
 448         acpi_status status;
 449         int result;
 450         struct acpi_pci_root *root;
 451         acpi_handle handle;
 452         struct acpi_device *child;
 453         u32 flags, base_flags;
 454
 455         root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
 456         if (!root)
 457                 return -ENOMEM;
 458
 459         segment = 0;
 460         status = acpi_evaluate_integer(device->handle, METHOD_NAME__SEG, NULL,
 461                                        &segment);
 462         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 463                 printk(KERN_ERR PREFIX "can't evaluate _SEG\n");
 464                 result = -ENODEV;
 465                 goto end;
 466         }
 467
 468         /* Check _CRS first, then _BBN.  If no _BBN, default to zero. */
 469         root->secondary.flags = IORESOURCE_BUS;
 470         status = try_get_root_bridge_busnr(device->handle, &root->secondary);
 471         if (ACPI_FAILURE(status)) {
 472                 /*
 473                  * We need both the start and end of the downstream bus range
 474                  * to interpret _CBA (MMCONFIG base address), so it really is
 475                  * supposed to be in _CRS.  If we don't find it there, all we
 476                  * can do is assume [_BBN-0xFF] or [0-0xFF].
 477                  */
 478                 root->secondary.end = 0xFF;
 479                 printk(KERN_WARNING FW_BUG PREFIX
 480                        "no secondary bus range in _CRS\n");
 481                 status = acpi_evaluate_integer(device->handle, METHOD_NAME__BBN,                                               NULL, &bus);
 482                 if (ACPI_SUCCESS(status))
 483                         root->secondary.start = bus;
 484                 else if (status == AE_NOT_FOUND)
 485                         root->secondary.start = 0;
 486                 else {
 487                         printk(KERN_ERR PREFIX "can't evaluate _BBN\n");
 488                         result = -ENODEV;
 489                         goto end;
 490                 }
 491         }
 492
 493         INIT_LIST_HEAD(&root->node);
 494         root->device = device;
 495         root->segment = segment & 0xFFFF;
 496         strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
 497         strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
 498         device->driver_data = root;
 499
 500         /*
 501          * All supported architectures that use ACPI have support for
 502          * PCI domains, so we indicate this in _OSC support capabilities.
 503          */
 504         flags = base_flags = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
 505         acpi_pci_osc_support(root, flags);
 506
 507         /*
 508          * TBD: Need PCI interface for enumeration/configuration of roots.
 509          */
 510
 511         /* TBD: Locking */
 512         list_add_tail(&root->node, &acpi_pci_roots);
 513
 514         printk(KERN_INFO PREFIX "%s [%s] (domain %04x %pR)\n",
 515                acpi_device_name(device), acpi_device_bid(device),
 516                root->segment, &root->secondary);
 517
 518         /*
 519          * Scan the Root Bridge
 520          * --------------------
 521          * Must do this prior to any attempt to bind the root device, as the
 522          * PCI namespace does not get created until this call is made (and
 523          * thus the root bridge's pci_dev does not exist).
 524          */
 525         root->bus = pci_acpi_scan_root(root);
 526         if (!root->bus) {
 527                 printk(KERN_ERR PREFIX
 528                             "Bus %04x:%02x not present in PCI namespace\n",
 529                             root->segment, (unsigned int)root->secondary.start);
 530                 result = -ENODEV;
 531                 goto end;
 532         }
 533
 534         /*
 535          * Attach ACPI-PCI Context
 536          * -----------------------
 537          * Thus binding the ACPI and PCI devices.
 538          */
 539         result = acpi_pci_bind_root(device);
 540         if (result)
 541                 goto end;
 542
 543         /*
 544          * PCI Routing Table
 545          * -----------------
 546          * Evaluate and parse _PRT, if exists.
 547          */
 548         status = acpi_get_handle(device->handle, METHOD_NAME__PRT, &handle);
 549         if (ACPI_SUCCESS(status))
 550                 result = acpi_pci_irq_add_prt(device->handle, root->bus);
 551
 552         /*
 553          * Scan and bind all _ADR-Based Devices
 554          */
 555         list_for_each_entry(child, &device->children, node)
 556                 acpi_pci_bridge_scan(child);
 557
 558         /* Indicate support for various _OSC capabilities. */
 559         if (pci_ext_cfg_avail(root->bus->self))
 560                 flags |= OSC_EXT_PCI_CONFIG_SUPPORT;
 561         if (pcie_aspm_enabled())
 562                 flags |= OSC_ACTIVE_STATE_PWR_SUPPORT |
 563                         OSC_CLOCK_PWR_CAPABILITY_SUPPORT;
 564         if (pci_msi_enabled())
 565                 flags |= OSC_MSI_SUPPORT;
 566         if (flags != base_flags)
 567                 acpi_pci_osc_support(root, flags);
 568
 569         pci_acpi_add_bus_pm_notifier(device, root->bus);
 570         if (device->wakeup.flags.run_wake)
 571                 device_set_run_wake(root->bus->bridge, true);
 572
 573         return 0;
 574
 575 end:
 576         if (!list_empty(&root->node))
 577                 list_del(&root->node);
 578         kfree(root);
 579         return result;
 580 }
 581
 582 static int acpi_pci_root_start(struct acpi_device *device)
 583 {
 584         struct acpi_pci_root *root = acpi_driver_data(device);
 585
 586         pci_bus_add_devices(root->bus);
 587         return 0;
 588 }
 589
 590 static int acpi_pci_root_remove(struct acpi_device *device, int type)
 591 {
 592         struct acpi_pci_root *root = acpi_driver_data(device);
 593
 594         device_set_run_wake(root->bus->bridge, false);
 595         pci_acpi_remove_bus_pm_notifier(device);
 596
 597         kfree(root);
 598         return 0;
 599 }
 600
 601 static int __init acpi_pci_root_init(void)
 602 {
 603         if (acpi_pci_disabled)
 604                 return 0;
 605
 606         pci_acpi_crs_quirks();
 607         if (acpi_bus_register_driver(&acpi_pci_root_driver) < 0)
 608                 return -ENODEV;
 609
 610         return 0;
 611 }
 612
 613 subsys_initcall(acpi_pci_root_init);