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