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 #include <linux/slab.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_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         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 220         union acpi_object *package, *fields;
 221         int i;
 222
 223         memset(hpp, 0, sizeof(struct hotplug_params));
 224
 225         status = acpi_evaluate_object(handle, "_HPP", NULL, &buffer);
 226         if (ACPI_FAILURE(status))
 227                 return status;
 228
 229         package = (union acpi_object *) buffer.pointer;
 230         if (package->type != ACPI_TYPE_PACKAGE ||
 231             package->package.count != 4) {
 232                 status = AE_ERROR;
 233                 goto exit;
 234         }
 235
 236         fields = package->package.elements;
 237         for (i = 0; i < 4; i++) {
 238                 if (fields[i].type != ACPI_TYPE_INTEGER) {
 239                         status = AE_ERROR;
 240                         goto exit;
 241                 }
 242         }
 243
 244         hpp->t0 = &hpp->type0_data;
 245         hpp->t0->revision        = 1;
 246         hpp->t0->cache_line_size = fields[0].integer.value;
 247         hpp->t0->latency_timer   = fields[1].integer.value;
 248         hpp->t0->enable_serr     = fields[2].integer.value;
 249         hpp->t0->enable_perr     = fields[3].integer.value;
 250
 251 exit:
 252         kfree(buffer.pointer);
 253         return status;
 254 }
 255
 256
 257
 258 /* acpi_run_oshp - get control of hotplug from the firmware
 259  *
 260  * @handle - the handle of the hotplug controller.
 261  */
 262 static acpi_status acpi_run_oshp(acpi_handle handle)
 263 {
 264         acpi_status             status;
 265         struct acpi_buffer      string = { ACPI_ALLOCATE_BUFFER, NULL };
 266
 267         acpi_get_name(handle, ACPI_FULL_PATHNAME, &string);
 268
 269         /* run OSHP */
 270         status = acpi_evaluate_object(handle, METHOD_NAME_OSHP, NULL, NULL);
 271         if (ACPI_FAILURE(status))
 272                 if (status != AE_NOT_FOUND)
 273                         printk(KERN_ERR "%s:%s OSHP fails=0x%x\n",
 274                                __func__, (char *)string.pointer, status);
 275                 else
 276                         dbg("%s:%s OSHP not found\n",
 277                             __func__, (char *)string.pointer);
 278         else
 279                 pr_debug("%s:%s OSHP passes\n", __func__,
 280                         (char *)string.pointer);
 281
 282         kfree(string.pointer);
 283         return status;
 284 }
 285
 286 /* pci_get_hp_params
 287  *
 288  * @dev - the pci_dev for which we want parameters
 289  * @hpp - allocated by the caller
 290  */
 291 int pci_get_hp_params(struct pci_dev *dev, struct hotplug_params *hpp)
 292 {
 293         acpi_status status;
 294         acpi_handle handle, phandle;
 295         struct pci_bus *pbus;
 296
 297         handle = NULL;
 298         for (pbus = dev->bus; pbus; pbus = pbus->parent) {
 299                 handle = acpi_pci_get_bridge_handle(pbus);
 300                 if (handle)
 301                         break;
 302         }
 303
 304         /*
 305          * _HPP settings apply to all child buses, until another _HPP is
 306          * encountered. If we don't find an _HPP for the input pci dev,
 307          * look for it in the parent device scope since that would apply to
 308          * this pci dev.
 309          */
 310         while (handle) {
 311                 status = acpi_run_hpx(handle, hpp);
 312                 if (ACPI_SUCCESS(status))
 313                         return 0;
 314                 status = acpi_run_hpp(handle, hpp);
 315                 if (ACPI_SUCCESS(status))
 316                         return 0;
 317                 if (acpi_is_root_bridge(handle))
 318                         break;
 319                 status = acpi_get_parent(handle, &phandle);
 320                 if (ACPI_FAILURE(status))
 321                         break;
 322                 handle = phandle;
 323         }
 324         return -ENODEV;
 325 }
 326 EXPORT_SYMBOL_GPL(pci_get_hp_params);
 327
 328 /**
 329  * acpi_get_hp_hw_control_from_firmware
 330  * @dev: the pci_dev of the bridge that has a hotplug controller
 331  * @flags: requested control bits for _OSC
 332  *
 333  * Attempt to take hotplug control from firmware.
 334  */
 335 int acpi_get_hp_hw_control_from_firmware(struct pci_dev *pdev, u32 flags)
 336 {
 337         acpi_status status;
 338         acpi_handle chandle, handle;
 339         struct acpi_buffer string = { ACPI_ALLOCATE_BUFFER, NULL };
 340
 341         flags &= (OSC_PCI_EXPRESS_NATIVE_HP_CONTROL |
 342                   OSC_SHPC_NATIVE_HP_CONTROL |
 343                   OSC_PCI_EXPRESS_CAP_STRUCTURE_CONTROL);
 344         if (!flags) {
 345                 err("Invalid flags %u specified!\n", flags);
 346                 return -EINVAL;
 347         }
 348
 349         /*
 350          * Per PCI firmware specification, we should run the ACPI _OSC
 351          * method to get control of hotplug hardware before using it. If
 352          * an _OSC is missing, we look for an OSHP to do the same thing.
 353          * To handle different BIOS behavior, we look for _OSC on a root
 354          * bridge preferentially (according to PCI fw spec). Later for
 355          * OSHP within the scope of the hotplug controller and its parents,
 356          * upto the host bridge under which this controller exists.
 357          */
 358         handle = acpi_find_root_bridge_handle(pdev);
 359         if (handle) {
 360                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &string);
 361                 dbg("Trying to get hotplug control for %s\n",
 362                                 (char *)string.pointer);
 363                 status = acpi_pci_osc_control_set(handle, flags);
 364                 if (ACPI_SUCCESS(status))
 365                         goto got_one;
 366                 if (status == AE_SUPPORT)
 367                         goto no_control;
 368                 kfree(string.pointer);
 369                 string = (struct acpi_buffer){ ACPI_ALLOCATE_BUFFER, NULL };
 370         }
 371
 372         handle = DEVICE_ACPI_HANDLE(&pdev->dev);
 373         if (!handle) {
 374                 /*
 375                  * This hotplug controller was not listed in the ACPI name
 376                  * space at all. Try to get acpi handle of parent pci bus.
 377                  */
 378                 struct pci_bus *pbus;
 379                 for (pbus = pdev->bus; pbus; pbus = pbus->parent) {
 380                         handle = acpi_pci_get_bridge_handle(pbus);
 381                         if (handle)
 382                                 break;
 383                 }
 384         }
 385
 386         while (handle) {
 387                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &string);
 388                 dbg("Trying to get hotplug control for %s \n",
 389                     (char *)string.pointer);
 390                 status = acpi_run_oshp(handle);
 391                 if (ACPI_SUCCESS(status))
 392                         goto got_one;
 393                 if (acpi_is_root_bridge(handle))
 394                         break;
 395                 chandle = handle;
 396                 status = acpi_get_parent(chandle, &handle);
 397                 if (ACPI_FAILURE(status))
 398                         break;
 399         }
 400 no_control:
 401         dbg("Cannot get control of hotplug hardware for pci %s\n",
 402             pci_name(pdev));
 403         kfree(string.pointer);
 404         return -ENODEV;
 405 got_one:
 406         dbg("Gained control for hotplug HW for pci %s (%s)\n",
 407             pci_name(pdev), (char *)string.pointer);
 408         kfree(string.pointer);
 409         return 0;
 410 }
 411 EXPORT_SYMBOL(acpi_get_hp_hw_control_from_firmware);
 412
 413 static int is_ejectable(acpi_handle handle)
 414 {
 415         acpi_status status;
 416         acpi_handle tmp;
 417         unsigned long long removable;
 418         status = acpi_get_handle(handle, "_ADR", &tmp);
 419         if (ACPI_FAILURE(status))
 420                 return 0;
 421         status = acpi_get_handle(handle, "_EJ0", &tmp);
 422         if (ACPI_SUCCESS(status))
 423                 return 1;
 424         status = acpi_evaluate_integer(handle, "_RMV", NULL, &removable);
 425         if (ACPI_SUCCESS(status) && removable)
 426                 return 1;
 427         return 0;
 428 }
 429
 430 /**
 431  * acpi_pcihp_check_ejectable - check if handle is ejectable ACPI PCI slot
 432  * @pbus: the PCI bus of the PCI slot corresponding to 'handle'
 433  * @handle: ACPI handle to check
 434  *
 435  * Return 1 if handle is ejectable PCI slot, 0 otherwise.
 436  */
 437 int acpi_pci_check_ejectable(struct pci_bus *pbus, acpi_handle handle)
 438 {
 439         acpi_handle bridge_handle, parent_handle;
 440
 441         if (!(bridge_handle = acpi_pci_get_bridge_handle(pbus)))
 442                 return 0;
 443         if ((ACPI_FAILURE(acpi_get_parent(handle, &parent_handle))))
 444                 return 0;
 445         if (bridge_handle != parent_handle)
 446                 return 0;
 447         return is_ejectable(handle);
 448 }
 449 EXPORT_SYMBOL_GPL(acpi_pci_check_ejectable);
 450
 451 static acpi_status
 452 check_hotplug(acpi_handle handle, u32 lvl, void *context, void **rv)
 453 {
 454         int *found = (int *)context;
 455         if (is_ejectable(handle)) {
 456                 *found = 1;
 457                 return AE_CTRL_TERMINATE;
 458         }
 459         return AE_OK;
 460 }
 461
 462 /**
 463  * acpi_pci_detect_ejectable - check if the PCI bus has ejectable slots
 464  * @handle - handle of the PCI bus to scan
 465  *
 466  * Returns 1 if the PCI bus has ACPI based ejectable slots, 0 otherwise.
 467  */
 468 int acpi_pci_detect_ejectable(acpi_handle handle)
 469 {
 470         int found = 0;
 471
 472         if (!handle)
 473                 return found;
 474
 475         acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
 476                             check_hotplug, NULL, (void *)&found, NULL);
 477         return found;
 478 }
 479 EXPORT_SYMBOL_GPL(acpi_pci_detect_ejectable);
 480
 481 module_param(debug_acpi, bool, 0644);
 482 MODULE_PARM_DESC(debug_acpi, "Debugging mode for ACPI enabled or not");