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 struct acpi_pci_root {
  67         struct list_head node;
  68         struct acpi_device *device;
  69         struct pci_bus *bus;
  70         u16 segment;
  71         u8 bus_nr;
  72
  73         u32 osc_support_set;    /* _OSC state of support bits */
  74         u32 osc_control_set;    /* _OSC state of control bits */
  75         u32 osc_control_qry;    /* the latest _OSC query result */
  76
  77         u32 osc_queried:1;      /* has _OSC control been queried? */
  78 };
  79
  80 static LIST_HEAD(acpi_pci_roots);
  81
  82 static struct acpi_pci_driver *sub_driver;
  83 static DEFINE_MUTEX(osc_lock);
  84
  85 int acpi_pci_register_driver(struct acpi_pci_driver *driver)
  86 {
  87         int n = 0;
  88         struct acpi_pci_root *root;
  89
  90         struct acpi_pci_driver **pptr = &sub_driver;
  91         while (*pptr)
  92                 pptr = &(*pptr)->next;
  93         *pptr = driver;
  94
  95         if (!driver->add)
  96                 return 0;
  97
  98         list_for_each_entry(root, &acpi_pci_roots, node) {
  99                 driver->add(root->device->handle);
 100                 n++;
 101         }
 102
 103         return n;
 104 }
 105
 106 EXPORT_SYMBOL(acpi_pci_register_driver);
 107
 108 void acpi_pci_unregister_driver(struct acpi_pci_driver *driver)
 109 {
 110         struct acpi_pci_root *root;
 111
 112         struct acpi_pci_driver **pptr = &sub_driver;
 113         while (*pptr) {
 114                 if (*pptr == driver)
 115                         break;
 116                 pptr = &(*pptr)->next;
 117         }
 118         BUG_ON(!*pptr);
 119         *pptr = (*pptr)->next;
 120
 121         if (!driver->remove)
 122                 return;
 123
 124         list_for_each_entry(root, &acpi_pci_roots, node)
 125                 driver->remove(root->device->handle);
 126 }
 127
 128 EXPORT_SYMBOL(acpi_pci_unregister_driver);
 129
 130 acpi_handle acpi_get_pci_rootbridge_handle(unsigned int seg, unsigned int bus)
 131 {
 132         struct acpi_pci_root *root;
 133
 134         list_for_each_entry(root, &acpi_pci_roots, node)
 135                 if ((root->segment == (u16) seg) && (root->bus_nr == (u16) bus))
 136                         return root->device->handle;
 137         return NULL;
 138 }
 139
 140 EXPORT_SYMBOL_GPL(acpi_get_pci_rootbridge_handle);
 141
 142 /**
 143  * acpi_is_root_bridge - determine whether an ACPI CA node is a PCI root bridge
 144  * @handle - the ACPI CA node in question.
 145  *
 146  * Note: we could make this API take a struct acpi_device * instead, but
 147  * for now, it's more convenient to operate on an acpi_handle.
 148  */
 149 int acpi_is_root_bridge(acpi_handle handle)
 150 {
 151         int ret;
 152         struct acpi_device *device;
 153
 154         ret = acpi_bus_get_device(handle, &device);
 155         if (ret)
 156                 return 0;
 157
 158         ret = acpi_match_device_ids(device, root_device_ids);
 159         if (ret)
 160                 return 0;
 161         else
 162                 return 1;
 163 }
 164 EXPORT_SYMBOL_GPL(acpi_is_root_bridge);
 165
 166 static acpi_status
 167 get_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
 168 {
 169         int *busnr = data;
 170         struct acpi_resource_address64 address;
 171
 172         if (resource->type != ACPI_RESOURCE_TYPE_ADDRESS16 &&
 173             resource->type != ACPI_RESOURCE_TYPE_ADDRESS32 &&
 174             resource->type != ACPI_RESOURCE_TYPE_ADDRESS64)
 175                 return AE_OK;
 176
 177         acpi_resource_to_address64(resource, &address);
 178         if ((address.address_length > 0) &&
 179             (address.resource_type == ACPI_BUS_NUMBER_RANGE))
 180                 *busnr = address.minimum;
 181
 182         return AE_OK;
 183 }
 184
 185 static acpi_status try_get_root_bridge_busnr(acpi_handle handle,
 186                                              unsigned long long *bus)
 187 {
 188         acpi_status status;
 189         int busnum;
 190
 191         busnum = -1;
 192         status =
 193             acpi_walk_resources(handle, METHOD_NAME__CRS,
 194                                 get_root_bridge_busnr_callback, &busnum);
 195         if (ACPI_FAILURE(status))
 196                 return status;
 197         /* Check if we really get a bus number from _CRS */
 198         if (busnum == -1)
 199                 return AE_ERROR;
 200         *bus = busnum;
 201         return AE_OK;
 202 }
 203
 204 static void acpi_pci_bridge_scan(struct acpi_device *device)
 205 {
 206         int status;
 207         struct acpi_device *child = NULL;
 208
 209         if (device->flags.bus_address)
 210                 if (device->parent && device->parent->ops.bind) {
 211                         status = device->parent->ops.bind(device);
 212                         if (!status) {
 213                                 list_for_each_entry(child, &device->children, node)
 214                                         acpi_pci_bridge_scan(child);
 215                         }
 216                 }
 217 }
 218
 219 static u8 OSC_UUID[16] = {0x5B, 0x4D, 0xDB, 0x33, 0xF7, 0x1F, 0x1C, 0x40,
 220                           0x96, 0x57, 0x74, 0x41, 0xC0, 0x3D, 0xD7, 0x66};
 221
 222 static acpi_status acpi_pci_run_osc(acpi_handle handle,
 223                                     const u32 *capbuf, u32 *retval)
 224 {
 225         acpi_status status;
 226         struct acpi_object_list input;
 227         union acpi_object in_params[4];
 228         struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL};
 229         union acpi_object *out_obj;
 230         u32 errors;
 231
 232         /* Setting up input parameters */
 233         input.count = 4;
 234         input.pointer = in_params;
 235         in_params[0].type               = ACPI_TYPE_BUFFER;
 236         in_params[0].buffer.length      = 16;
 237         in_params[0].buffer.pointer     = OSC_UUID;
 238         in_params[1].type               = ACPI_TYPE_INTEGER;
 239         in_params[1].integer.value      = 1;
 240         in_params[2].type               = ACPI_TYPE_INTEGER;
 241         in_params[2].integer.value      = 3;
 242         in_params[3].type               = ACPI_TYPE_BUFFER;
 243         in_params[3].buffer.length      = 12;
 244         in_params[3].buffer.pointer     = (u8 *)capbuf;
 245
 246         status = acpi_evaluate_object(handle, "_OSC", &input, &output);
 247         if (ACPI_FAILURE(status))
 248                 return status;
 249
 250         if (!output.length)
 251                 return AE_NULL_OBJECT;
 252
 253         out_obj = output.pointer;
 254         if (out_obj->type != ACPI_TYPE_BUFFER) {
 255                 printk(KERN_DEBUG "_OSC evaluation returned wrong type\n");
 256                 status = AE_TYPE;
 257                 goto out_kfree;
 258         }
 259         /* Need to ignore the bit0 in result code */
 260         errors = *((u32 *)out_obj->buffer.pointer) & ~(1 << 0);
 261         if (errors) {
 262                 if (errors & OSC_REQUEST_ERROR)
 263                         printk(KERN_DEBUG "_OSC request failed\n");
 264                 if (errors & OSC_INVALID_UUID_ERROR)
 265                         printk(KERN_DEBUG "_OSC invalid UUID\n");
 266                 if (errors & OSC_INVALID_REVISION_ERROR)
 267                         printk(KERN_DEBUG "_OSC invalid revision\n");
 268                 if (errors & OSC_CAPABILITIES_MASK_ERROR) {
 269                         if (capbuf[OSC_QUERY_TYPE] & OSC_QUERY_ENABLE)
 270                                 goto out_success;
 271                         printk(KERN_DEBUG
 272                                "Firmware did not grant requested _OSC control\n");
 273                         status = AE_SUPPORT;
 274                         goto out_kfree;
 275                 }
 276                 status = AE_ERROR;
 277                 goto out_kfree;
 278         }
 279 out_success:
 280         *retval = *((u32 *)(out_obj->buffer.pointer + 8));
 281         status = AE_OK;
 282
 283 out_kfree:
 284         kfree(output.pointer);
 285         return status;
 286 }
 287
 288 static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root, u32 flags)
 289 {
 290         acpi_status status;
 291         u32 support_set, result, capbuf[3];
 292
 293         /* do _OSC query for all possible controls */
 294         support_set = root->osc_support_set | (flags & OSC_SUPPORT_MASKS);
 295         capbuf[OSC_QUERY_TYPE] = OSC_QUERY_ENABLE;
 296         capbuf[OSC_SUPPORT_TYPE] = support_set;
 297         capbuf[OSC_CONTROL_TYPE] = OSC_CONTROL_MASKS;
 298
 299         status = acpi_pci_run_osc(root->device->handle, capbuf, &result);
 300         if (ACPI_SUCCESS(status)) {
 301                 root->osc_support_set = support_set;
 302                 root->osc_control_qry = result;
 303                 root->osc_queried = 1;
 304         }
 305         return status;
 306 }
 307
 308 static acpi_status acpi_pci_osc_support(struct acpi_pci_root *root, u32 flags)
 309 {
 310         acpi_status status;
 311         acpi_handle tmp;
 312
 313         status = acpi_get_handle(root->device->handle, "_OSC", &tmp);
 314         if (ACPI_FAILURE(status))
 315                 return status;
 316         mutex_lock(&osc_lock);
 317         status = acpi_pci_query_osc(root, flags);
 318         mutex_unlock(&osc_lock);
 319         return status;
 320 }
 321
 322 static struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle)
 323 {
 324         struct acpi_pci_root *root;
 325
 326         list_for_each_entry(root, &acpi_pci_roots, node) {
 327                 if (root->device->handle == handle)
 328                         return root;
 329         }
 330         return NULL;
 331 }
 332
 333 struct acpi_handle_node {
 334         struct list_head node;
 335         acpi_handle handle;
 336 };
 337
 338 /**
 339  * acpi_get_pci_dev - convert ACPI CA handle to struct pci_dev
 340  * @handle: the handle in question
 341  *
 342  * Given an ACPI CA handle, the desired PCI device is located in the
 343  * list of PCI devices.
 344  *
 345  * If the device is found, its reference count is increased and this
 346  * function returns a pointer to its data structure.  The caller must
 347  * decrement the reference count by calling pci_dev_put().
 348  * If no device is found, %NULL is returned.
 349  */
 350 struct pci_dev *acpi_get_pci_dev(acpi_handle handle)
 351 {
 352         int dev, fn;
 353         unsigned long long adr;
 354         acpi_status status;
 355         acpi_handle phandle;
 356         struct pci_bus *pbus;
 357         struct pci_dev *pdev = NULL;
 358         struct acpi_handle_node *node, *tmp;
 359         struct acpi_pci_root *root;
 360         LIST_HEAD(device_list);
 361
 362         /*
 363          * Walk up the ACPI CA namespace until we reach a PCI root bridge.
 364          */
 365         phandle = handle;
 366         while (!acpi_is_root_bridge(phandle)) {
 367                 node = kzalloc(sizeof(struct acpi_handle_node), GFP_KERNEL);
 368                 if (!node)
 369                         goto out;
 370
 371                 INIT_LIST_HEAD(&node->node);
 372                 node->handle = phandle;
 373                 list_add(&node->node, &device_list);
 374
 375                 status = acpi_get_parent(phandle, &phandle);
 376                 if (ACPI_FAILURE(status))
 377                         goto out;
 378         }
 379
 380         root = acpi_pci_find_root(phandle);
 381         if (!root)
 382                 goto out;
 383
 384         pbus = root->bus;
 385
 386         /*
 387          * Now, walk back down the PCI device tree until we return to our
 388          * original handle. Assumes that everything between the PCI root
 389          * bridge and the device we're looking for must be a P2P bridge.
 390          */
 391         list_for_each_entry(node, &device_list, node) {
 392                 acpi_handle hnd = node->handle;
 393                 status = acpi_evaluate_integer(hnd, "_ADR", NULL, &adr);
 394                 if (ACPI_FAILURE(status))
 395                         goto out;
 396                 dev = (adr >> 16) & 0xffff;
 397                 fn  = adr & 0xffff;
 398
 399                 pdev = pci_get_slot(pbus, PCI_DEVFN(dev, fn));
 400                 if (!pdev || hnd == handle)
 401                         break;
 402
 403                 pbus = pdev->subordinate;
 404                 pci_dev_put(pdev);
 405         }
 406 out:
 407         list_for_each_entry_safe(node, tmp, &device_list, node)
 408                 kfree(node);
 409
 410         return pdev;
 411 }
 412 EXPORT_SYMBOL_GPL(acpi_get_pci_dev);
 413
 414 /**
 415  * acpi_pci_osc_control_set - commit requested control to Firmware
 416  * @handle: acpi_handle for the target ACPI object
 417  * @flags: driver's requested control bits
 418  *
 419  * Attempt to take control from Firmware on requested control bits.
 420  **/
 421 acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 flags)
 422 {
 423         acpi_status status;
 424         u32 control_req, result, capbuf[3];
 425         acpi_handle tmp;
 426         struct acpi_pci_root *root;
 427
 428         status = acpi_get_handle(handle, "_OSC", &tmp);
 429         if (ACPI_FAILURE(status))
 430                 return status;
 431
 432         control_req = (flags & OSC_CONTROL_MASKS);
 433         if (!control_req)
 434                 return AE_TYPE;
 435
 436         root = acpi_pci_find_root(handle);
 437         if (!root)
 438                 return AE_NOT_EXIST;
 439
 440         mutex_lock(&osc_lock);
 441         /* No need to evaluate _OSC if the control was already granted. */
 442         if ((root->osc_control_set & control_req) == control_req)
 443                 goto out;
 444
 445         /* Need to query controls first before requesting them */
 446         if (!root->osc_queried) {
 447                 status = acpi_pci_query_osc(root, root->osc_support_set);
 448                 if (ACPI_FAILURE(status))
 449                         goto out;
 450         }
 451         if ((root->osc_control_qry & control_req) != control_req) {
 452                 printk(KERN_DEBUG
 453                        "Firmware did not grant requested _OSC control\n");
 454                 status = AE_SUPPORT;
 455                 goto out;
 456         }
 457
 458         capbuf[OSC_QUERY_TYPE] = 0;
 459         capbuf[OSC_SUPPORT_TYPE] = root->osc_support_set;
 460         capbuf[OSC_CONTROL_TYPE] = root->osc_control_set | control_req;
 461         status = acpi_pci_run_osc(handle, capbuf, &result);
 462         if (ACPI_SUCCESS(status))
 463                 root->osc_control_set = result;
 464 out:
 465         mutex_unlock(&osc_lock);
 466         return status;
 467 }
 468 EXPORT_SYMBOL(acpi_pci_osc_control_set);
 469
 470 static int __devinit acpi_pci_root_add(struct acpi_device *device)
 471 {
 472         unsigned long long segment, bus;
 473         acpi_status status;
 474         int result;
 475         struct acpi_pci_root *root;
 476         acpi_handle handle;
 477         struct acpi_device *child;
 478         u32 flags, base_flags;
 479
 480         segment = 0;
 481         status = acpi_evaluate_integer(device->handle, METHOD_NAME__SEG, NULL,
 482                                        &segment);
 483         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 484                 printk(KERN_ERR PREFIX "can't evaluate _SEG\n");
 485                 return -ENODEV;
 486         }
 487
 488         /* Check _CRS first, then _BBN.  If no _BBN, default to zero. */
 489         bus = 0;
 490         status = try_get_root_bridge_busnr(device->handle, &bus);
 491         if (ACPI_FAILURE(status)) {
 492                 status = acpi_evaluate_integer(device->handle, METHOD_NAME__BBN,                                               NULL, &bus);
 493                 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 494                         printk(KERN_ERR PREFIX
 495                              "no bus number in _CRS and can't evaluate _BBN\n");
 496                         return -ENODEV;
 497                 }
 498         }
 499
 500         root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
 501         if (!root)
 502                 return -ENOMEM;
 503
 504         INIT_LIST_HEAD(&root->node);
 505         root->device = device;
 506         root->segment = segment & 0xFFFF;
 507         root->bus_nr = bus & 0xFF;
 508         strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
 509         strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
 510         device->driver_data = root;
 511
 512         /*
 513          * All supported architectures that use ACPI have support for
 514          * PCI domains, so we indicate this in _OSC support capabilities.
 515          */
 516         flags = base_flags = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
 517         acpi_pci_osc_support(root, flags);
 518
 519         /*
 520          * TBD: Need PCI interface for enumeration/configuration of roots.
 521          */
 522
 523         /* TBD: Locking */
 524         list_add_tail(&root->node, &acpi_pci_roots);
 525
 526         printk(KERN_INFO PREFIX "%s [%s] (%04x:%02x)\n",
 527                acpi_device_name(device), acpi_device_bid(device),
 528                root->segment, root->bus_nr);
 529
 530         /*
 531          * Scan the Root Bridge
 532          * --------------------
 533          * Must do this prior to any attempt to bind the root device, as the
 534          * PCI namespace does not get created until this call is made (and
 535          * thus the root bridge's pci_dev does not exist).
 536          */
 537         root->bus = pci_acpi_scan_root(device, segment, bus);
 538         if (!root->bus) {
 539                 printk(KERN_ERR PREFIX
 540                             "Bus %04x:%02x not present in PCI namespace\n",
 541                             root->segment, root->bus_nr);
 542                 result = -ENODEV;
 543                 goto end;
 544         }
 545
 546         /*
 547          * Attach ACPI-PCI Context
 548          * -----------------------
 549          * Thus binding the ACPI and PCI devices.
 550          */
 551         result = acpi_pci_bind_root(device);
 552         if (result)
 553                 goto end;
 554
 555         /*
 556          * PCI Routing Table
 557          * -----------------
 558          * Evaluate and parse _PRT, if exists.
 559          */
 560         status = acpi_get_handle(device->handle, METHOD_NAME__PRT, &handle);
 561         if (ACPI_SUCCESS(status))
 562                 result = acpi_pci_irq_add_prt(device->handle, root->bus);
 563
 564         /*
 565          * Scan and bind all _ADR-Based Devices
 566          */
 567         list_for_each_entry(child, &device->children, node)
 568                 acpi_pci_bridge_scan(child);
 569
 570         /* Indicate support for various _OSC capabilities. */
 571         if (pci_ext_cfg_avail(root->bus->self))
 572                 flags |= OSC_EXT_PCI_CONFIG_SUPPORT;
 573         if (pcie_aspm_enabled())
 574                 flags |= OSC_ACTIVE_STATE_PWR_SUPPORT |
 575                         OSC_CLOCK_PWR_CAPABILITY_SUPPORT;
 576         if (pci_msi_enabled())
 577                 flags |= OSC_MSI_SUPPORT;
 578         if (flags != base_flags)
 579                 acpi_pci_osc_support(root, flags);
 580
 581         return 0;
 582
 583 end:
 584         if (!list_empty(&root->node))
 585                 list_del(&root->node);
 586         kfree(root);
 587         return result;
 588 }
 589
 590 static int acpi_pci_root_start(struct acpi_device *device)
 591 {
 592         struct acpi_pci_root *root = acpi_driver_data(device);
 593
 594         pci_bus_add_devices(root->bus);
 595         return 0;
 596 }
 597
 598 static int acpi_pci_root_remove(struct acpi_device *device, int type)
 599 {
 600         struct acpi_pci_root *root = acpi_driver_data(device);
 601
 602         kfree(root);
 603         return 0;
 604 }
 605
 606 static int __init acpi_pci_root_init(void)
 607 {
 608         if (acpi_pci_disabled)
 609                 return 0;
 610
 611         if (acpi_bus_register_driver(&acpi_pci_root_driver) < 0)
 612                 return -ENODEV;
 613
 614         return 0;
 615 }
 616
 617 subsys_initcall(acpi_pci_root_init);