drivers/pci/hotplug/acpi_pcihp.c

   1 /*
   2  * Common ACPI functions for hot plug platforms
   3  *
   4  * Copyright (C) 2006 Intel Corporation
   5  *
   6  * All rights reserved.
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or (at
  11  * your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful, but
  14  * WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
  16  * NON INFRINGEMENT.  See the GNU General Public License for more
  17  * details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  22  *
  23  * Send feedback to <kristen.c.accardi@intel.com>
  24  *
  25  */
  26
  27 #include <linux/module.h>
  28 #include <linux/moduleparam.h>
  29 #include <linux/kernel.h>
  30 #include <linux/types.h>
  31 #include <linux/pci.h>
  32 #include <linux/pci_hotplug.h>
  33 #include <linux/pci-acpi.h>
  34 #include <acpi/acpi.h>
  35 #include <acpi/acpi_bus.h>
  36
  37 #define MY_NAME "acpi_pcihp"
  38
  39 #define dbg(fmt, arg...) do { if (debug_acpi) printk(KERN_DEBUG "%s: %s: " fmt , MY_NAME , __func__ , ## arg); } while (0)
  40 #define err(format, arg...) printk(KERN_ERR "%s: " format , MY_NAME , ## arg)
  41 #define info(format, arg...) printk(KERN_INFO "%s: " format , MY_NAME , ## arg)
  42 #define warn(format, arg...) printk(KERN_WARNING "%s: " format , MY_NAME , ## arg)
  43
  44 #define METHOD_NAME__SUN        "_SUN"
  45 #define METHOD_NAME__HPP        "_HPP"
  46 #define METHOD_NAME_OSHP        "OSHP"
  47
  48 static int debug_acpi;
  49
  50 static acpi_status
  51 decode_type0_hpx_record(union acpi_object *record, struct hotplug_params *hpx)
  52 {
  53         int i;
  54         union acpi_object *fields = record->package.elements;
  55         u32 revision = fields[1].integer.value;
  56
  57         switch (revision) {
  58         case 1:
  59                 if (record->package.count != 6)
  60                         return AE_ERROR;
  61                 for (i = 2; i < 6; i++)
  62                         if (fields[i].type != ACPI_TYPE_INTEGER)
  63                                 return AE_ERROR;
  64                 hpx->t0 = &hpx->type0_data;
  65                 hpx->t0->revision        = revision;
  66                 hpx->t0->cache_line_size = fields[2].integer.value;
  67                 hpx->t0->latency_timer   = fields[3].integer.value;
  68                 hpx->t0->enable_serr     = fields[4].integer.value;
  69                 hpx->t0->enable_perr     = fields[5].integer.value;
  70                 break;
  71         default:
  72                 printk(KERN_WARNING
  73                        "%s: Type 0 Revision %d record not supported\n",
  74                        __func__, revision);
  75                 return AE_ERROR;
  76         }
  77         return AE_OK;
  78 }
  79
  80 static acpi_status
  81 decode_type1_hpx_record(union acpi_object *record, struct hotplug_params *hpx)
  82 {
  83         int i;
  84         union acpi_object *fields = record->package.elements;
  85         u32 revision = fields[1].integer.value;
  86
  87         switch (revision) {
  88         case 1:
  89                 if (record->package.count != 5)
  90                         return AE_ERROR;
  91                 for (i = 2; i < 5; i++)
  92                         if (fields[i].type != ACPI_TYPE_INTEGER)
  93                                 return AE_ERROR;
  94                 hpx->t1 = &hpx->type1_data;
  95                 hpx->t1->revision      = revision;
  96                 hpx->t1->max_mem_read  = fields[2].integer.value;
  97                 hpx->t1->avg_max_split = fields[3].integer.value;
  98                 hpx->t1->tot_max_split = fields[4].integer.value;
  99                 break;
 100         default:
 101                 printk(KERN_WARNING
 102                        "%s: Type 1 Revision %d record not supported\n",
 103                        __func__, revision);
 104                 return AE_ERROR;
 105         }
 106         return AE_OK;
 107 }
 108
 109 static acpi_status
 110 decode_type2_hpx_record(union acpi_object *record, struct hotplug_params *hpx)
 111 {
 112         int i;
 113         union acpi_object *fields = record->package.elements;
 114         u32 revision = fields[1].integer.value;
 115
 116         switch (revision) {
 117         case 1:
 118                 if (record->package.count != 18)
 119                         return AE_ERROR;
 120                 for (i = 2; i < 18; i++)
 121                         if (fields[i].type != ACPI_TYPE_INTEGER)
 122                                 return AE_ERROR;
 123                 hpx->t2 = &hpx->type2_data;
 124                 hpx->t2->revision      = revision;
 125                 hpx->t2->unc_err_mask_and      = fields[2].integer.value;
 126                 hpx->t2->unc_err_mask_or       = fields[3].integer.value;
 127                 hpx->t2->unc_err_sever_and     = fields[4].integer.value;
 128                 hpx->t2->unc_err_sever_or      = fields[5].integer.value;
 129                 hpx->t2->cor_err_mask_and      = fields[6].integer.value;
 130                 hpx->t2->cor_err_mask_or       = fields[7].integer.value;
 131                 hpx->t2->adv_err_cap_and       = fields[8].integer.value;
 132                 hpx->t2->adv_err_cap_or        = fields[9].integer.value;
 133                 hpx->t2->pci_exp_devctl_and    = fields[10].integer.value;
 134                 hpx->t2->pci_exp_devctl_or     = fields[11].integer.value;
 135                 hpx->t2->pci_exp_lnkctl_and    = fields[12].integer.value;
 136                 hpx->t2->pci_exp_lnkctl_or     = fields[13].integer.value;
 137                 hpx->t2->sec_unc_err_sever_and = fields[14].integer.value;
 138                 hpx->t2->sec_unc_err_sever_or  = fields[15].integer.value;
 139                 hpx->t2->sec_unc_err_mask_and  = fields[16].integer.value;
 140                 hpx->t2->sec_unc_err_mask_or   = fields[17].integer.value;
 141                 break;
 142         default:
 143                 printk(KERN_WARNING
 144                        "%s: Type 2 Revision %d record not supported\n",
 145                        __func__, revision);
 146                 return AE_ERROR;
 147         }
 148         return AE_OK;
 149 }
 150
 151 static acpi_status
 152 acpi_run_hpx(acpi_handle handle, struct hotplug_params *hpx)
 153 {
 154         acpi_status status;
 155         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
 156         union acpi_object *package, *record, *fields;
 157         u32 type;
 158         int i;
 159
 160         /* Clear the return buffer with zeros */
 161         memset(hpx, 0, sizeof(struct hotplug_params));
 162
 163         status = acpi_evaluate_object(handle, "_HPX", NULL, &buffer);
 164         if (ACPI_FAILURE(status))
 165                 return status;
 166
 167         package = (union acpi_object *)buffer.pointer;
 168         if (package->type != ACPI_TYPE_PACKAGE) {
 169                 status = AE_ERROR;
 170                 goto exit;
 171         }
 172
 173         for (i = 0; i < package->package.count; i++) {
 174                 record = &package->package.elements[i];
 175                 if (record->type != ACPI_TYPE_PACKAGE) {
 176                         status = AE_ERROR;
 177                         goto exit;
 178                 }
 179
 180                 fields = record->package.elements;
 181                 if (fields[0].type != ACPI_TYPE_INTEGER ||
 182                     fields[1].type != ACPI_TYPE_INTEGER) {
 183                         status = AE_ERROR;
 184                         goto exit;
 185                 }
 186
 187                 type = fields[0].integer.value;
 188                 switch (type) {
 189                 case 0:
 190                         status = decode_type0_hpx_record(record, hpx);
 191                         if (ACPI_FAILURE(status))
 192                                 goto exit;
 193                         break;
 194                 case 1:
 195                         status = decode_type1_hpx_record(record, hpx);
 196                         if (ACPI_FAILURE(status))
 197                                 goto exit;
 198                         break;
 199                 case 2:
 200                         status = decode_type2_hpx_record(record, hpx);
 201                         if (ACPI_FAILURE(status))
 202                                 goto exit;
 203                         break;
 204                 default:
 205                         printk(KERN_ERR "%s: Type %d record not supported\n",
 206                                __func__, type);
 207                         status = AE_ERROR;
 208                         goto exit;
 209                 }
 210         }
 211  exit:
 212         kfree(buffer.pointer);
 213         return status;
 214 }
 215
 216 static acpi_status
 217 acpi_run_hpp(acpi_handle handle, struct hotplug_params *hpp)
 218 {
 219         acpi_status             status;
 220         u8                      nui[4];
 221         struct acpi_buffer      ret_buf = { 0, NULL};
 222         struct acpi_buffer      string = { ACPI_ALLOCATE_BUFFER, NULL };
 223         union acpi_object       *ext_obj, *package;
 224         int                     i, len = 0;
 225
 226         acpi_get_name(handle, ACPI_FULL_PATHNAME, &string);
 227
 228         /* Clear the return buffer with zeros */
 229         memset(hpp, 0, sizeof(struct hotplug_params));
 230
 231         /* get _hpp */
 232         status = acpi_evaluate_object(handle, METHOD_NAME__HPP, NULL, &ret_buf);
 233         switch (status) {
 234         case AE_BUFFER_OVERFLOW:
 235                 ret_buf.pointer = kmalloc (ret_buf.length, GFP_KERNEL);
 236                 if (!ret_buf.pointer) {
 237                         printk(KERN_ERR "%s:%s alloc for _HPP fail\n",
 238                                 __func__, (char *)string.pointer);
 239                         kfree(string.pointer);
 240                         return AE_NO_MEMORY;
 241                 }
 242                 status = acpi_evaluate_object(handle, METHOD_NAME__HPP,
 243                                 NULL, &ret_buf);
 244                 if (ACPI_SUCCESS(status))
 245                         break;
 246         default:
 247                 if (ACPI_FAILURE(status)) {
 248                         pr_debug("%s:%s _HPP fail=0x%x\n", __func__,
 249                                 (char *)string.pointer, status);
 250                         kfree(string.pointer);
 251                         return status;
 252                 }
 253         }
 254
 255         ext_obj = (union acpi_object *) ret_buf.pointer;
 256         if (ext_obj->type != ACPI_TYPE_PACKAGE) {
 257                 printk(KERN_ERR "%s:%s _HPP obj not a package\n", __func__,
 258                                 (char *)string.pointer);
 259                 status = AE_ERROR;
 260                 goto free_and_return;
 261         }
 262
 263         len = ext_obj->package.count;
 264         package = (union acpi_object *) ret_buf.pointer;
 265         for ( i = 0; (i < len) || (i < 4); i++) {
 266                 ext_obj = (union acpi_object *) &package->package.elements[i];
 267                 switch (ext_obj->type) {
 268                 case ACPI_TYPE_INTEGER:
 269                         nui[i] = (u8)ext_obj->integer.value;
 270                         break;
 271                 default:
 272                         printk(KERN_ERR "%s:%s _HPP obj type incorrect\n",
 273                                 __func__, (char *)string.pointer);
 274                         status = AE_ERROR;
 275                         goto free_and_return;
 276                 }
 277         }
 278
 279         hpp->t0 = &hpp->type0_data;
 280         hpp->t0->cache_line_size = nui[0];
 281         hpp->t0->latency_timer = nui[1];
 282         hpp->t0->enable_serr = nui[2];
 283         hpp->t0->enable_perr = nui[3];
 284
 285         pr_debug("  _HPP: cache_line_size=0x%x\n", hpp->t0->cache_line_size);
 286         pr_debug("  _HPP: latency timer  =0x%x\n", hpp->t0->latency_timer);
 287         pr_debug("  _HPP: enable SERR    =0x%x\n", hpp->t0->enable_serr);
 288         pr_debug("  _HPP: enable PERR    =0x%x\n", hpp->t0->enable_perr);
 289
 290 free_and_return:
 291         kfree(string.pointer);
 292         kfree(ret_buf.pointer);
 293         return status;
 294 }
 295
 296
 297
 298 /* acpi_run_oshp - get control of hotplug from the firmware
 299  *
 300  * @handle - the handle of the hotplug controller.
 301  */
 302 static acpi_status acpi_run_oshp(acpi_handle handle)
 303 {
 304         acpi_status             status;
 305         struct acpi_buffer      string = { ACPI_ALLOCATE_BUFFER, NULL };
 306
 307         acpi_get_name(handle, ACPI_FULL_PATHNAME, &string);
 308
 309         /* run OSHP */
 310         status = acpi_evaluate_object(handle, METHOD_NAME_OSHP, NULL, NULL);
 311         if (ACPI_FAILURE(status))
 312                 if (status != AE_NOT_FOUND)
 313                         printk(KERN_ERR "%s:%s OSHP fails=0x%x\n",
 314                                __func__, (char *)string.pointer, status);
 315                 else
 316                         dbg("%s:%s OSHP not found\n",
 317                             __func__, (char *)string.pointer);
 318         else
 319                 pr_debug("%s:%s OSHP passes\n", __func__,
 320                         (char *)string.pointer);
 321
 322         kfree(string.pointer);
 323         return status;
 324 }
 325
 326 /* acpi_get_hp_params_from_firmware
 327  *
 328  * @bus - the pci_bus of the bus on which the device is newly added
 329  * @hpp - allocated by the caller
 330  */
 331 acpi_status acpi_get_hp_params_from_firmware(struct pci_bus *bus,
 332                 struct hotplug_params *hpp)
 333 {
 334         acpi_status status = AE_NOT_FOUND;
 335         acpi_handle handle, phandle;
 336         struct pci_bus *pbus = bus;
 337         struct pci_dev *pdev;
 338
 339         do {
 340                 pdev = pbus->self;
 341                 if (!pdev) {
 342                         handle = acpi_get_pci_rootbridge_handle(
 343                                 pci_domain_nr(pbus), pbus->number);
 344                         break;
 345                 }
 346                 handle = DEVICE_ACPI_HANDLE(&(pdev->dev));
 347                 pbus = pbus->parent;
 348         } while (!handle);
 349
 350         /*
 351          * _HPP settings apply to all child buses, until another _HPP is
 352          * encountered. If we don't find an _HPP for the input pci dev,
 353          * look for it in the parent device scope since that would apply to
 354          * this pci dev. If we don't find any _HPP, use hardcoded defaults
 355          */
 356         while (handle) {
 357                 status = acpi_run_hpx(handle, hpp);
 358                 if (ACPI_SUCCESS(status))
 359                         break;
 360                 status = acpi_run_hpp(handle, hpp);
 361                 if (ACPI_SUCCESS(status))
 362                         break;
 363                 if (acpi_root_bridge(handle))
 364                         break;
 365                 status = acpi_get_parent(handle, &phandle);
 366                 if (ACPI_FAILURE(status))
 367                         break;
 368                 handle = phandle;
 369         }
 370         return status;
 371 }
 372 EXPORT_SYMBOL_GPL(acpi_get_hp_params_from_firmware);
 373
 374 /**
 375  * acpi_get_hp_hw_control_from_firmware
 376  * @dev: the pci_dev of the bridge that has a hotplug controller
 377  * @flags: requested control bits for _OSC
 378  *
 379  * Attempt to take hotplug control from firmware.
 380  */
 381 int acpi_get_hp_hw_control_from_firmware(struct pci_dev *dev, u32 flags)
 382 {
 383         acpi_status status;
 384         acpi_handle chandle, handle;
 385         struct pci_dev *pdev = dev;
 386         struct pci_bus *parent;
 387         struct acpi_buffer string = { ACPI_ALLOCATE_BUFFER, NULL };
 388
 389         flags &= (OSC_PCI_EXPRESS_NATIVE_HP_CONTROL |
 390                   OSC_SHPC_NATIVE_HP_CONTROL |
 391                   OSC_PCI_EXPRESS_CAP_STRUCTURE_CONTROL);
 392         if (!flags) {
 393                 err("Invalid flags %u specified!\n", flags);
 394                 return -EINVAL;
 395         }
 396
 397         /*
 398          * Per PCI firmware specification, we should run the ACPI _OSC
 399          * method to get control of hotplug hardware before using it. If
 400          * an _OSC is missing, we look for an OSHP to do the same thing.
 401          * To handle different BIOS behavior, we look for _OSC on a root
 402          * bridge preferentially (according to PCI fw spec). Later for
 403          * OSHP within the scope of the hotplug controller and its parents,
 404          * upto the host bridge under which this controller exists.
 405          */
 406         handle = acpi_find_root_bridge_handle(pdev);
 407         if (handle) {
 408                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &string);
 409                 dbg("Trying to get hotplug control for %s\n",
 410                                 (char *)string.pointer);
 411                 status = pci_osc_control_set(handle, flags);
 412                 if (ACPI_SUCCESS(status))
 413                         goto got_one;
 414                 kfree(string.pointer);
 415                 string = (struct acpi_buffer){ ACPI_ALLOCATE_BUFFER, NULL };
 416         }
 417
 418         pdev = dev;
 419         handle = DEVICE_ACPI_HANDLE(&dev->dev);
 420         while (!handle) {
 421                 /*
 422                  * This hotplug controller was not listed in the ACPI name
 423                  * space at all. Try to get acpi handle of parent pci bus.
 424                  */
 425                 if (!pdev || !pdev->bus->parent)
 426                         break;
 427                 parent = pdev->bus->parent;
 428                 dbg("Could not find %s in acpi namespace, trying parent\n",
 429                     pci_name(pdev));
 430                 if (!parent->self)
 431                         /* Parent must be a host bridge */
 432                         handle = acpi_get_pci_rootbridge_handle(
 433                                         pci_domain_nr(parent),
 434                                         parent->number);
 435                 else
 436                         handle = DEVICE_ACPI_HANDLE(&(parent->self->dev));
 437                 pdev = parent->self;
 438         }
 439
 440         while (handle) {
 441                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &string);
 442                 dbg("Trying to get hotplug control for %s \n",
 443                     (char *)string.pointer);
 444                 status = acpi_run_oshp(handle);
 445                 if (ACPI_SUCCESS(status))
 446                         goto got_one;
 447                 if (acpi_root_bridge(handle))
 448                         break;
 449                 chandle = handle;
 450                 status = acpi_get_parent(chandle, &handle);
 451                 if (ACPI_FAILURE(status))
 452                         break;
 453         }
 454
 455         dbg("Cannot get control of hotplug hardware for pci %s\n",
 456             pci_name(dev));
 457
 458         kfree(string.pointer);
 459         return -ENODEV;
 460 got_one:
 461         dbg("Gained control for hotplug HW for pci %s (%s)\n", pci_name(dev),
 462                         (char *)string.pointer);
 463         kfree(string.pointer);
 464         return 0;
 465 }
 466 EXPORT_SYMBOL(acpi_get_hp_hw_control_from_firmware);
 467
 468 /* acpi_root_bridge - check to see if this acpi object is a root bridge
 469  *
 470  * @handle - the acpi object in question.
 471  */
 472 int acpi_root_bridge(acpi_handle handle)
 473 {
 474         acpi_status status;
 475         struct acpi_device_info *info;
 476         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
 477         int i;
 478
 479         status = acpi_get_object_info(handle, &buffer);
 480         if (ACPI_SUCCESS(status)) {
 481                 info = buffer.pointer;
 482                 if ((info->valid & ACPI_VALID_HID) &&
 483                         !strcmp(PCI_ROOT_HID_STRING,
 484                                         info->hardware_id.value)) {
 485                         kfree(buffer.pointer);
 486                         return 1;
 487                 }
 488                 if (info->valid & ACPI_VALID_CID) {
 489                         for (i=0; i < info->compatibility_id.count; i++) {
 490                                 if (!strcmp(PCI_ROOT_HID_STRING,
 491                                         info->compatibility_id.id[i].value)) {
 492                                         kfree(buffer.pointer);
 493                                         return 1;
 494                                 }
 495                         }
 496                 }
 497                 kfree(buffer.pointer);
 498         }
 499         return 0;
 500 }
 501 EXPORT_SYMBOL_GPL(acpi_root_bridge);
 502
 503
 504 static int is_ejectable(acpi_handle handle)
 505 {
 506         acpi_status status;
 507         acpi_handle tmp;
 508         unsigned long long removable;
 509         status = acpi_get_handle(handle, "_ADR", &tmp);
 510         if (ACPI_FAILURE(status))
 511                 return 0;
 512         status = acpi_get_handle(handle, "_EJ0", &tmp);
 513         if (ACPI_SUCCESS(status))
 514                 return 1;
 515         status = acpi_evaluate_integer(handle, "_RMV", NULL, &removable);
 516         if (ACPI_SUCCESS(status) && removable)
 517                 return 1;
 518         return 0;
 519 }
 520
 521 /**
 522  * acpi_pcihp_check_ejectable - check if handle is ejectable ACPI PCI slot
 523  * @pbus: the PCI bus of the PCI slot corresponding to 'handle'
 524  * @handle: ACPI handle to check
 525  *
 526  * Return 1 if handle is ejectable PCI slot, 0 otherwise.
 527  */
 528 int acpi_pci_check_ejectable(struct pci_bus *pbus, acpi_handle handle)
 529 {
 530         acpi_handle bridge_handle, parent_handle;
 531
 532         if (!(bridge_handle = acpi_pci_get_bridge_handle(pbus)))
 533                 return 0;
 534         if ((ACPI_FAILURE(acpi_get_parent(handle, &parent_handle))))
 535                 return 0;
 536         if (bridge_handle != parent_handle)
 537                 return 0;
 538         return is_ejectable(handle);
 539 }
 540 EXPORT_SYMBOL_GPL(acpi_pci_check_ejectable);
 541
 542 static acpi_status
 543 check_hotplug(acpi_handle handle, u32 lvl, void *context, void **rv)
 544 {
 545         int *found = (int *)context;
 546         if (is_ejectable(handle)) {
 547                 *found = 1;
 548                 return AE_CTRL_TERMINATE;
 549         }
 550         return AE_OK;
 551 }
 552
 553 /**
 554  * acpi_pci_detect_ejectable - check if the PCI bus has ejectable slots
 555  * @pbus - PCI bus to scan
 556  *
 557  * Returns 1 if the PCI bus has ACPI based ejectable slots, 0 otherwise.
 558  */
 559 int acpi_pci_detect_ejectable(struct pci_bus *pbus)
 560 {
 561         acpi_handle handle;
 562         int found = 0;
 563
 564         if (!(handle = acpi_pci_get_bridge_handle(pbus)))
 565                 return 0;
 566         acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, (u32)1,
 567                             check_hotplug, (void *)&found, NULL);
 568         return found;
 569 }
 570 EXPORT_SYMBOL_GPL(acpi_pci_detect_ejectable);
 571
 572 module_param(debug_acpi, bool, 0644);
 573 MODULE_PARM_DESC(debug_acpi, "Debugging mode for ACPI enabled or not");