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