drivers/acpi/acpica/evgpeinit.c

   1 /******************************************************************************
   2  *
   3  * Module Name: evgpeinit - System GPE initialization and update
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2011, Intel Corp.
   9  * All rights reserved.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions, and the following disclaimer,
  16  *    without modification.
  17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  18  *    substantially similar to the "NO WARRANTY" disclaimer below
  19  *    ("Disclaimer") and any redistribution must be conditioned upon
  20  *    including a substantially similar Disclaimer requirement for further
  21  *    binary redistribution.
  22  * 3. Neither the names of the above-listed copyright holders nor the names
  23  *    of any contributors may be used to endorse or promote products derived
  24  *    from this software without specific prior written permission.
  25  *
  26  * Alternatively, this software may be distributed under the terms of the
  27  * GNU General Public License ("GPL") version 2 as published by the Free
  28  * Software Foundation.
  29  *
  30  * NO WARRANTY
  31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
  34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  41  * POSSIBILITY OF SUCH DAMAGES.
  42  */
  43
  44 #include <acpi/acpi.h>
  45 #include "accommon.h"
  46 #include "acevents.h"
  47 #include "acnamesp.h"
  48
  49 #define _COMPONENT          ACPI_EVENTS
  50 ACPI_MODULE_NAME("evgpeinit")
  51
  52 /*
  53  * Note: History of _PRW support in ACPICA
  54  *
  55  * Originally (2000 - 2010), the GPE initialization code performed a walk of
  56  * the entire namespace to execute the _PRW methods and detect all GPEs
  57  * capable of waking the system.
  58  *
  59  * As of 10/2010, the _PRW method execution has been removed since it is
  60  * actually unnecessary. The host OS must in fact execute all _PRW methods
  61  * in order to identify the device/power-resource dependencies. We now put
  62  * the onus on the host OS to identify the wake GPEs as part of this process
  63  * and to inform ACPICA of these GPEs via the acpi_setup_gpe_for_wake interface. This
  64  * not only reduces the complexity of the ACPICA initialization code, but in
  65  * some cases (on systems with very large namespaces) it should reduce the
  66  * kernel boot time as well.
  67  */
  68
  69 /*******************************************************************************
  70  *
  71  * FUNCTION:    acpi_ev_gpe_initialize
  72  *
  73  * PARAMETERS:  None
  74  *
  75  * RETURN:      Status
  76  *
  77  * DESCRIPTION: Initialize the GPE data structures and the FADT GPE 0/1 blocks
  78  *
  79  ******************************************************************************/
  80 acpi_status acpi_ev_gpe_initialize(void)
  81 {
  82         u32 register_count0 = 0;
  83         u32 register_count1 = 0;
  84         u32 gpe_number_max = 0;
  85         acpi_status status;
  86
  87         ACPI_FUNCTION_TRACE(ev_gpe_initialize);
  88
  89         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
  90         if (ACPI_FAILURE(status)) {
  91                 return_ACPI_STATUS(status);
  92         }
  93
  94         /*
  95          * Initialize the GPE Block(s) defined in the FADT
  96          *
  97          * Why the GPE register block lengths are divided by 2:  From the ACPI
  98          * Spec, section "General-Purpose Event Registers", we have:
  99          *
 100          * "Each register block contains two registers of equal length
 101          *  GPEx_STS and GPEx_EN (where x is 0 or 1). The length of the
 102          *  GPE0_STS and GPE0_EN registers is equal to half the GPE0_LEN
 103          *  The length of the GPE1_STS and GPE1_EN registers is equal to
 104          *  half the GPE1_LEN. If a generic register block is not supported
 105          *  then its respective block pointer and block length values in the
 106          *  FADT table contain zeros. The GPE0_LEN and GPE1_LEN do not need
 107          *  to be the same size."
 108          */
 109
 110         /*
 111          * Determine the maximum GPE number for this machine.
 112          *
 113          * Note: both GPE0 and GPE1 are optional, and either can exist without
 114          * the other.
 115          *
 116          * If EITHER the register length OR the block address are zero, then that
 117          * particular block is not supported.
 118          */
 119         if (acpi_gbl_FADT.gpe0_block_length &&
 120             acpi_gbl_FADT.xgpe0_block.address) {
 121
 122                 /* GPE block 0 exists (has both length and address > 0) */
 123
 124                 register_count0 = (u16)(acpi_gbl_FADT.gpe0_block_length / 2);
 125
 126                 gpe_number_max =
 127                     (register_count0 * ACPI_GPE_REGISTER_WIDTH) - 1;
 128
 129                 /* Install GPE Block 0 */
 130
 131                 status = acpi_ev_create_gpe_block(acpi_gbl_fadt_gpe_device,
 132                                                   &acpi_gbl_FADT.xgpe0_block,
 133                                                   register_count0, 0,
 134                                                   acpi_gbl_FADT.sci_interrupt,
 135                                                   &acpi_gbl_gpe_fadt_blocks[0]);
 136
 137                 if (ACPI_FAILURE(status)) {
 138                         ACPI_EXCEPTION((AE_INFO, status,
 139                                         "Could not create GPE Block 0"));
 140                 }
 141         }
 142
 143         if (acpi_gbl_FADT.gpe1_block_length &&
 144             acpi_gbl_FADT.xgpe1_block.address) {
 145
 146                 /* GPE block 1 exists (has both length and address > 0) */
 147
 148                 register_count1 = (u16)(acpi_gbl_FADT.gpe1_block_length / 2);
 149
 150                 /* Check for GPE0/GPE1 overlap (if both banks exist) */
 151
 152                 if ((register_count0) &&
 153                     (gpe_number_max >= acpi_gbl_FADT.gpe1_base)) {
 154                         ACPI_ERROR((AE_INFO,
 155                                     "GPE0 block (GPE 0 to %u) overlaps the GPE1 block "
 156                                     "(GPE %u to %u) - Ignoring GPE1",
 157                                     gpe_number_max, acpi_gbl_FADT.gpe1_base,
 158                                     acpi_gbl_FADT.gpe1_base +
 159                                     ((register_count1 *
 160                                       ACPI_GPE_REGISTER_WIDTH) - 1)));
 161
 162                         /* Ignore GPE1 block by setting the register count to zero */
 163
 164                         register_count1 = 0;
 165                 } else {
 166                         /* Install GPE Block 1 */
 167
 168                         status =
 169                             acpi_ev_create_gpe_block(acpi_gbl_fadt_gpe_device,
 170                                                      &acpi_gbl_FADT.xgpe1_block,
 171                                                      register_count1,
 172                                                      acpi_gbl_FADT.gpe1_base,
 173                                                      acpi_gbl_FADT.
 174                                                      sci_interrupt,
 175                                                      &acpi_gbl_gpe_fadt_blocks
 176                                                      [1]);
 177
 178                         if (ACPI_FAILURE(status)) {
 179                                 ACPI_EXCEPTION((AE_INFO, status,
 180                                                 "Could not create GPE Block 1"));
 181                         }
 182
 183                         /*
 184                          * GPE0 and GPE1 do not have to be contiguous in the GPE number
 185                          * space. However, GPE0 always starts at GPE number zero.
 186                          */
 187                         gpe_number_max = acpi_gbl_FADT.gpe1_base +
 188                             ((register_count1 * ACPI_GPE_REGISTER_WIDTH) - 1);
 189                 }
 190         }
 191
 192         /* Exit if there are no GPE registers */
 193
 194         if ((register_count0 + register_count1) == 0) {
 195
 196                 /* GPEs are not required by ACPI, this is OK */
 197
 198                 ACPI_DEBUG_PRINT((ACPI_DB_INIT,
 199                                   "There are no GPE blocks defined in the FADT\n"));
 200                 status = AE_OK;
 201                 goto cleanup;
 202         }
 203
 204         /* Check for Max GPE number out-of-range */
 205
 206         if (gpe_number_max > ACPI_GPE_MAX) {
 207                 ACPI_ERROR((AE_INFO,
 208                             "Maximum GPE number from FADT is too large: 0x%X",
 209                             gpe_number_max));
 210                 status = AE_BAD_VALUE;
 211                 goto cleanup;
 212         }
 213
 214       cleanup:
 215         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 216         return_ACPI_STATUS(AE_OK);
 217 }
 218
 219 /*******************************************************************************
 220  *
 221  * FUNCTION:    acpi_ev_update_gpes
 222  *
 223  * PARAMETERS:  table_owner_id      - ID of the newly-loaded ACPI table
 224  *
 225  * RETURN:      None
 226  *
 227  * DESCRIPTION: Check for new GPE methods (_Lxx/_Exx) made available as a
 228  *              result of a Load() or load_table() operation. If new GPE
 229  *              methods have been installed, register the new methods.
 230  *
 231  ******************************************************************************/
 232
 233 void acpi_ev_update_gpes(acpi_owner_id table_owner_id)
 234 {
 235         struct acpi_gpe_xrupt_info *gpe_xrupt_info;
 236         struct acpi_gpe_block_info *gpe_block;
 237         struct acpi_gpe_walk_info walk_info;
 238         acpi_status status = AE_OK;
 239
 240         /*
 241          * Find any _Lxx/_Exx GPE methods that have just been loaded.
 242          *
 243          * Any GPEs that correspond to new _Lxx/_Exx methods are immediately
 244          * enabled.
 245          *
 246          * Examine the namespace underneath each gpe_device within the
 247          * gpe_block lists.
 248          */
 249         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 250         if (ACPI_FAILURE(status)) {
 251                 return;
 252         }
 253
 254         walk_info.count = 0;
 255         walk_info.owner_id = table_owner_id;
 256         walk_info.execute_by_owner_id = TRUE;
 257
 258         /* Walk the interrupt level descriptor list */
 259
 260         gpe_xrupt_info = acpi_gbl_gpe_xrupt_list_head;
 261         while (gpe_xrupt_info) {
 262
 263                 /* Walk all Gpe Blocks attached to this interrupt level */
 264
 265                 gpe_block = gpe_xrupt_info->gpe_block_list_head;
 266                 while (gpe_block) {
 267                         walk_info.gpe_block = gpe_block;
 268                         walk_info.gpe_device = gpe_block->node;
 269
 270                         status = acpi_ns_walk_namespace(ACPI_TYPE_METHOD,
 271                                                         walk_info.gpe_device,
 272                                                         ACPI_UINT32_MAX,
 273                                                         ACPI_NS_WALK_NO_UNLOCK,
 274                                                         acpi_ev_match_gpe_method,
 275                                                         NULL, &walk_info, NULL);
 276                         if (ACPI_FAILURE(status)) {
 277                                 ACPI_EXCEPTION((AE_INFO, status,
 278                                                 "While decoding _Lxx/_Exx methods"));
 279                         }
 280
 281                         gpe_block = gpe_block->next;
 282                 }
 283
 284                 gpe_xrupt_info = gpe_xrupt_info->next;
 285         }
 286
 287         if (walk_info.count) {
 288                 ACPI_INFO((AE_INFO, "Enabled %u new GPEs", walk_info.count));
 289         }
 290
 291         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 292         return;
 293 }
 294
 295 /*******************************************************************************
 296  *
 297  * FUNCTION:    acpi_ev_match_gpe_method
 298  *
 299  * PARAMETERS:  Callback from walk_namespace
 300  *
 301  * RETURN:      Status
 302  *
 303  * DESCRIPTION: Called from acpi_walk_namespace. Expects each object to be a
 304  *              control method under the _GPE portion of the namespace.
 305  *              Extract the name and GPE type from the object, saving this
 306  *              information for quick lookup during GPE dispatch. Allows a
 307  *              per-owner_id evaluation if execute_by_owner_id is TRUE in the
 308  *              walk_info parameter block.
 309  *
 310  *              The name of each GPE control method is of the form:
 311  *              "_Lxx" or "_Exx", where:
 312  *                  L      - means that the GPE is level triggered
 313  *                  E      - means that the GPE is edge triggered
 314  *                  xx     - is the GPE number [in HEX]
 315  *
 316  * If walk_info->execute_by_owner_id is TRUE, we only execute examine GPE methods
 317  * with that owner.
 318  *
 319  ******************************************************************************/
 320
 321 acpi_status
 322 acpi_ev_match_gpe_method(acpi_handle obj_handle,
 323                          u32 level, void *context, void **return_value)
 324 {
 325         struct acpi_namespace_node *method_node =
 326             ACPI_CAST_PTR(struct acpi_namespace_node, obj_handle);
 327         struct acpi_gpe_walk_info *walk_info =
 328             ACPI_CAST_PTR(struct acpi_gpe_walk_info, context);
 329         struct acpi_gpe_event_info *gpe_event_info;
 330         u32 gpe_number;
 331         char name[ACPI_NAME_SIZE + 1];
 332         u8 type;
 333
 334         ACPI_FUNCTION_TRACE(ev_match_gpe_method);
 335
 336         /* Check if requested owner_id matches this owner_id */
 337
 338         if ((walk_info->execute_by_owner_id) &&
 339             (method_node->owner_id != walk_info->owner_id)) {
 340                 return_ACPI_STATUS(AE_OK);
 341         }
 342
 343         /*
 344          * Match and decode the _Lxx and _Exx GPE method names
 345          *
 346          * 1) Extract the method name and null terminate it
 347          */
 348         ACPI_MOVE_32_TO_32(name, &method_node->name.integer);
 349         name[ACPI_NAME_SIZE] = 0;
 350
 351         /* 2) Name must begin with an underscore */
 352
 353         if (name[0] != '_') {
 354                 return_ACPI_STATUS(AE_OK);      /* Ignore this method */
 355         }
 356
 357         /*
 358          * 3) Edge/Level determination is based on the 2nd character
 359          *    of the method name
 360          */
 361         switch (name[1]) {
 362         case 'L':
 363                 type = ACPI_GPE_LEVEL_TRIGGERED;
 364                 break;
 365
 366         case 'E':
 367                 type = ACPI_GPE_EDGE_TRIGGERED;
 368                 break;
 369
 370         default:
 371                 /* Unknown method type, just ignore it */
 372
 373                 ACPI_DEBUG_PRINT((ACPI_DB_LOAD,
 374                                   "Ignoring unknown GPE method type: %s "
 375                                   "(name not of form _Lxx or _Exx)", name));
 376                 return_ACPI_STATUS(AE_OK);
 377         }
 378
 379         /* 4) The last two characters of the name are the hex GPE Number */
 380
 381         gpe_number = ACPI_STRTOUL(&name[2], NULL, 16);
 382         if (gpe_number == ACPI_UINT32_MAX) {
 383
 384                 /* Conversion failed; invalid method, just ignore it */
 385
 386                 ACPI_DEBUG_PRINT((ACPI_DB_LOAD,
 387                                   "Could not extract GPE number from name: %s "
 388                                   "(name is not of form _Lxx or _Exx)", name));
 389                 return_ACPI_STATUS(AE_OK);
 390         }
 391
 392         /* Ensure that we have a valid GPE number for this GPE block */
 393
 394         gpe_event_info =
 395             acpi_ev_low_get_gpe_info(gpe_number, walk_info->gpe_block);
 396         if (!gpe_event_info) {
 397                 /*
 398                  * This gpe_number is not valid for this GPE block, just ignore it.
 399                  * However, it may be valid for a different GPE block, since GPE0
 400                  * and GPE1 methods both appear under \_GPE.
 401                  */
 402                 return_ACPI_STATUS(AE_OK);
 403         }
 404
 405         if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) ==
 406             ACPI_GPE_DISPATCH_HANDLER) {
 407
 408                 /* If there is already a handler, ignore this GPE method */
 409
 410                 return_ACPI_STATUS(AE_OK);
 411         }
 412
 413         if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) ==
 414             ACPI_GPE_DISPATCH_METHOD) {
 415                 /*
 416                  * If there is already a method, ignore this method. But check
 417                  * for a type mismatch (if both the _Lxx AND _Exx exist)
 418                  */
 419                 if (type != (gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK)) {
 420                         ACPI_ERROR((AE_INFO,
 421                                     "For GPE 0x%.2X, found both _L%2.2X and _E%2.2X methods",
 422                                     gpe_number, gpe_number, gpe_number));
 423                 }
 424                 return_ACPI_STATUS(AE_OK);
 425         }
 426
 427         /* Disable the GPE in case it's been enabled already. */
 428         (void)acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_DISABLE);
 429
 430         /*
 431          * Add the GPE information from above to the gpe_event_info block for
 432          * use during dispatch of this GPE.
 433          */
 434         gpe_event_info->flags &= ~(ACPI_GPE_DISPATCH_MASK);
 435         gpe_event_info->flags |= (u8)(type | ACPI_GPE_DISPATCH_METHOD);
 436         gpe_event_info->dispatch.method_node = method_node;
 437
 438         ACPI_DEBUG_PRINT((ACPI_DB_LOAD,
 439                           "Registered GPE method %s as GPE number 0x%.2X\n",
 440                           name, gpe_number));
 441         return_ACPI_STATUS(AE_OK);
 442 }