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