drivers/acpi/acpica/evgpeinit.c

   1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
   2 /******************************************************************************
   3  *
   4  * Module Name: evgpeinit - System GPE initialization and update
   5  *
   6  * Copyright (C) 2000 - 2020, Intel Corp.
   7  *
   8  *****************************************************************************/
   9
  10 #include <acpi/acpi.h>
  11 #include "accommon.h"
  12 #include "acevents.h"
  13 #include "acnamesp.h"
  14
  15 #define _COMPONENT          ACPI_EVENTS
  16 ACPI_MODULE_NAME("evgpeinit")
  17 #if (!ACPI_REDUCED_HARDWARE)    /* Entire module */
  18 /*
  19  * Note: History of _PRW support in ACPICA
  20  *
  21  * Originally (2000 - 2010), the GPE initialization code performed a walk of
  22  * the entire namespace to execute the _PRW methods and detect all GPEs
  23  * capable of waking the system.
  24  *
  25  * As of 10/2010, the _PRW method execution has been removed since it is
  26  * actually unnecessary. The host OS must in fact execute all _PRW methods
  27  * in order to identify the device/power-resource dependencies. We now put
  28  * the onus on the host OS to identify the wake GPEs as part of this process
  29  * and to inform ACPICA of these GPEs via the acpi_setup_gpe_for_wake interface. This
  30  * not only reduces the complexity of the ACPICA initialization code, but in
  31  * some cases (on systems with very large namespaces) it should reduce the
  32  * kernel boot time as well.
  33  */
  34
  35 #ifdef ACPI_GPE_USE_LOGICAL_ADDRESSES
  36 #define ACPI_FADT_GPE_BLOCK_ADDRESS(N)  \
  37         acpi_gbl_FADT.xgpe##N##_block.space_id == \
  38                                         ACPI_ADR_SPACE_SYSTEM_MEMORY ? \
  39                 (u64)acpi_gbl_xgpe##N##_block_logical_address : \
  40                 acpi_gbl_FADT.xgpe##N##_block.address
  41 #else
  42 #define ACPI_FADT_GPE_BLOCK_ADDRESS(N)  acpi_gbl_FADT.xgpe##N##_block.address
  43 #endif          /* ACPI_GPE_USE_LOGICAL_ADDRESSES */
  44
  45 /*******************************************************************************
  46  *
  47  * FUNCTION:    acpi_ev_gpe_initialize
  48  *
  49  * PARAMETERS:  None
  50  *
  51  * RETURN:      Status
  52  *
  53  * DESCRIPTION: Initialize the GPE data structures and the FADT GPE 0/1 blocks
  54  *
  55  ******************************************************************************/
  56 acpi_status acpi_ev_gpe_initialize(void)
  57 {
  58         u32 register_count0 = 0;
  59         u32 register_count1 = 0;
  60         u32 gpe_number_max = 0;
  61         acpi_status status;
  62         u64 address;
  63
  64         ACPI_FUNCTION_TRACE(ev_gpe_initialize);
  65
  66         ACPI_DEBUG_PRINT_RAW((ACPI_DB_INIT,
  67                               "Initializing General Purpose Events (GPEs):\n"));
  68
  69         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
  70         if (ACPI_FAILURE(status)) {
  71                 return_ACPI_STATUS(status);
  72         }
  73
  74         /*
  75          * Initialize the GPE Block(s) defined in the FADT
  76          *
  77          * Why the GPE register block lengths are divided by 2:  From the ACPI
  78          * Spec, section "General-Purpose Event Registers", we have:
  79          *
  80          * "Each register block contains two registers of equal length
  81          *  GPEx_STS and GPEx_EN (where x is 0 or 1). The length of the
  82          *  GPE0_STS and GPE0_EN registers is equal to half the GPE0_LEN
  83          *  The length of the GPE1_STS and GPE1_EN registers is equal to
  84          *  half the GPE1_LEN. If a generic register block is not supported
  85          *  then its respective block pointer and block length values in the
  86          *  FADT table contain zeros. The GPE0_LEN and GPE1_LEN do not need
  87          *  to be the same size."
  88          */
  89
  90         /*
  91          * Determine the maximum GPE number for this machine.
  92          *
  93          * Note: both GPE0 and GPE1 are optional, and either can exist without
  94          * the other.
  95          *
  96          * If EITHER the register length OR the block address are zero, then that
  97          * particular block is not supported.
  98          */
  99         address = ACPI_FADT_GPE_BLOCK_ADDRESS(0);
 100
 101         if (acpi_gbl_FADT.gpe0_block_length && address) {
 102
 103                 /* GPE block 0 exists (has both length and address > 0) */
 104
 105                 register_count0 = (u16)(acpi_gbl_FADT.gpe0_block_length / 2);
 106                 gpe_number_max =
 107                     (register_count0 * ACPI_GPE_REGISTER_WIDTH) - 1;
 108
 109                 /* Install GPE Block 0 */
 110
 111                 status = acpi_ev_create_gpe_block(acpi_gbl_fadt_gpe_device,
 112                                                   address,
 113                                                   acpi_gbl_FADT.xgpe0_block.
 114                                                   space_id, register_count0, 0,
 115                                                   acpi_gbl_FADT.sci_interrupt,
 116                                                   &acpi_gbl_gpe_fadt_blocks[0]);
 117
 118                 if (ACPI_FAILURE(status)) {
 119                         ACPI_EXCEPTION((AE_INFO, status,
 120                                         "Could not create GPE Block 0"));
 121                 }
 122         }
 123
 124         address = ACPI_FADT_GPE_BLOCK_ADDRESS(1);
 125
 126         if (acpi_gbl_FADT.gpe1_block_length && address) {
 127
 128                 /* GPE block 1 exists (has both length and address > 0) */
 129
 130                 register_count1 = (u16)(acpi_gbl_FADT.gpe1_block_length / 2);
 131
 132                 /* Check for GPE0/GPE1 overlap (if both banks exist) */
 133
 134                 if ((register_count0) &&
 135                     (gpe_number_max >= acpi_gbl_FADT.gpe1_base)) {
 136                         ACPI_ERROR((AE_INFO,
 137                                     "GPE0 block (GPE 0 to %u) overlaps the GPE1 block "
 138                                     "(GPE %u to %u) - Ignoring GPE1",
 139                                     gpe_number_max, acpi_gbl_FADT.gpe1_base,
 140                                     acpi_gbl_FADT.gpe1_base +
 141                                     ((register_count1 *
 142                                       ACPI_GPE_REGISTER_WIDTH) - 1)));
 143
 144                         /* Ignore GPE1 block by setting the register count to zero */
 145
 146                         register_count1 = 0;
 147                 } else {
 148                         /* Install GPE Block 1 */
 149
 150                         status =
 151                             acpi_ev_create_gpe_block(acpi_gbl_fadt_gpe_device,
 152                                                      address,
 153                                                      acpi_gbl_FADT.xgpe1_block.
 154                                                      space_id, register_count1,
 155                                                      acpi_gbl_FADT.gpe1_base,
 156                                                      acpi_gbl_FADT.
 157                                                      sci_interrupt,
 158                                                      &acpi_gbl_gpe_fadt_blocks
 159                                                      [1]);
 160
 161                         if (ACPI_FAILURE(status)) {
 162                                 ACPI_EXCEPTION((AE_INFO, status,
 163                                                 "Could not create GPE Block 1"));
 164                         }
 165
 166                         /*
 167                          * GPE0 and GPE1 do not have to be contiguous in the GPE number
 168                          * space. However, GPE0 always starts at GPE number zero.
 169                          */
 170                 }
 171         }
 172
 173         /* Exit if there are no GPE registers */
 174
 175         if ((register_count0 + register_count1) == 0) {
 176
 177                 /* GPEs are not required by ACPI, this is OK */
 178
 179                 ACPI_DEBUG_PRINT((ACPI_DB_INIT,
 180                                   "There are no GPE blocks defined in the FADT\n"));
 181                 goto cleanup;
 182         }
 183
 184 cleanup:
 185         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 186         return_ACPI_STATUS(AE_OK);
 187 }
 188
 189 /*******************************************************************************
 190  *
 191  * FUNCTION:    acpi_ev_update_gpes
 192  *
 193  * PARAMETERS:  table_owner_id      - ID of the newly-loaded ACPI table
 194  *
 195  * RETURN:      None
 196  *
 197  * DESCRIPTION: Check for new GPE methods (_Lxx/_Exx) made available as a
 198  *              result of a Load() or load_table() operation. If new GPE
 199  *              methods have been installed, register the new methods.
 200  *
 201  ******************************************************************************/
 202
 203 void acpi_ev_update_gpes(acpi_owner_id table_owner_id)
 204 {
 205         struct acpi_gpe_xrupt_info *gpe_xrupt_info;
 206         struct acpi_gpe_block_info *gpe_block;
 207         struct acpi_gpe_walk_info walk_info;
 208         acpi_status status = AE_OK;
 209
 210         /*
 211          * Find any _Lxx/_Exx GPE methods that have just been loaded.
 212          *
 213          * Any GPEs that correspond to new _Lxx/_Exx methods are immediately
 214          * enabled.
 215          *
 216          * Examine the namespace underneath each gpe_device within the
 217          * gpe_block lists.
 218          */
 219         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 220         if (ACPI_FAILURE(status)) {
 221                 return;
 222         }
 223
 224         walk_info.count = 0;
 225         walk_info.owner_id = table_owner_id;
 226         walk_info.execute_by_owner_id = TRUE;
 227
 228         /* Walk the interrupt level descriptor list */
 229
 230         gpe_xrupt_info = acpi_gbl_gpe_xrupt_list_head;
 231         while (gpe_xrupt_info) {
 232
 233                 /* Walk all Gpe Blocks attached to this interrupt level */
 234
 235                 gpe_block = gpe_xrupt_info->gpe_block_list_head;
 236                 while (gpe_block) {
 237                         walk_info.gpe_block = gpe_block;
 238                         walk_info.gpe_device = gpe_block->node;
 239
 240                         status = acpi_ns_walk_namespace(ACPI_TYPE_METHOD,
 241                                                         walk_info.gpe_device,
 242                                                         ACPI_UINT32_MAX,
 243                                                         ACPI_NS_WALK_NO_UNLOCK,
 244                                                         acpi_ev_match_gpe_method,
 245                                                         NULL, &walk_info, NULL);
 246                         if (ACPI_FAILURE(status)) {
 247                                 ACPI_EXCEPTION((AE_INFO, status,
 248                                                 "While decoding _Lxx/_Exx methods"));
 249                         }
 250
 251                         gpe_block = gpe_block->next;
 252                 }
 253
 254                 gpe_xrupt_info = gpe_xrupt_info->next;
 255         }
 256
 257         if (walk_info.count) {
 258                 ACPI_INFO(("Enabled %u new GPEs", walk_info.count));
 259         }
 260
 261         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 262         return;
 263 }
 264
 265 /*******************************************************************************
 266  *
 267  * FUNCTION:    acpi_ev_match_gpe_method
 268  *
 269  * PARAMETERS:  Callback from walk_namespace
 270  *
 271  * RETURN:      Status
 272  *
 273  * DESCRIPTION: Called from acpi_walk_namespace. Expects each object to be a
 274  *              control method under the _GPE portion of the namespace.
 275  *              Extract the name and GPE type from the object, saving this
 276  *              information for quick lookup during GPE dispatch. Allows a
 277  *              per-owner_id evaluation if execute_by_owner_id is TRUE in the
 278  *              walk_info parameter block.
 279  *
 280  *              The name of each GPE control method is of the form:
 281  *              "_Lxx" or "_Exx", where:
 282  *                  L      - means that the GPE is level triggered
 283  *                  E      - means that the GPE is edge triggered
 284  *                  xx     - is the GPE number [in HEX]
 285  *
 286  * If walk_info->execute_by_owner_id is TRUE, we only execute examine GPE methods
 287  * with that owner.
 288  *
 289  ******************************************************************************/
 290
 291 acpi_status
 292 acpi_ev_match_gpe_method(acpi_handle obj_handle,
 293                          u32 level, void *context, void **return_value)
 294 {
 295         struct acpi_namespace_node *method_node =
 296             ACPI_CAST_PTR(struct acpi_namespace_node, obj_handle);
 297         struct acpi_gpe_walk_info *walk_info =
 298             ACPI_CAST_PTR(struct acpi_gpe_walk_info, context);
 299         struct acpi_gpe_event_info *gpe_event_info;
 300         acpi_status status;
 301         u32 gpe_number;
 302         u8 temp_gpe_number;
 303         char name[ACPI_NAMESEG_SIZE + 1];
 304         u8 type;
 305
 306         ACPI_FUNCTION_TRACE(ev_match_gpe_method);
 307
 308         /* Check if requested owner_id matches this owner_id */
 309
 310         if ((walk_info->execute_by_owner_id) &&
 311             (method_node->owner_id != walk_info->owner_id)) {
 312                 return_ACPI_STATUS(AE_OK);
 313         }
 314
 315         /*
 316          * Match and decode the _Lxx and _Exx GPE method names
 317          *
 318          * 1) Extract the method name and null terminate it
 319          */
 320         ACPI_MOVE_32_TO_32(name, &method_node->name.integer);
 321         name[ACPI_NAMESEG_SIZE] = 0;
 322
 323         /* 2) Name must begin with an underscore */
 324
 325         if (name[0] != '_') {
 326                 return_ACPI_STATUS(AE_OK);      /* Ignore this method */
 327         }
 328
 329         /*
 330          * 3) Edge/Level determination is based on the 2nd character
 331          *    of the method name
 332          */
 333         switch (name[1]) {
 334         case 'L':
 335
 336                 type = ACPI_GPE_LEVEL_TRIGGERED;
 337                 break;
 338
 339         case 'E':
 340
 341                 type = ACPI_GPE_EDGE_TRIGGERED;
 342                 break;
 343
 344         default:
 345
 346                 /* Unknown method type, just ignore it */
 347
 348                 ACPI_DEBUG_PRINT((ACPI_DB_LOAD,
 349                                   "Ignoring unknown GPE method type: %s "
 350                                   "(name not of form _Lxx or _Exx)", name));
 351                 return_ACPI_STATUS(AE_OK);
 352         }
 353
 354         /* 4) The last two characters of the name are the hex GPE Number */
 355
 356         status = acpi_ut_ascii_to_hex_byte(&name[2], &temp_gpe_number);
 357         if (ACPI_FAILURE(status)) {
 358
 359                 /* Conversion failed; invalid method, just ignore it */
 360
 361                 ACPI_DEBUG_PRINT((ACPI_DB_LOAD,
 362                                   "Could not extract GPE number from name: %s "
 363                                   "(name is not of form _Lxx or _Exx)", name));
 364                 return_ACPI_STATUS(AE_OK);
 365         }
 366
 367         /* Ensure that we have a valid GPE number for this GPE block */
 368
 369         gpe_number = (u32)temp_gpe_number;
 370         gpe_event_info =
 371             acpi_ev_low_get_gpe_info(gpe_number, walk_info->gpe_block);
 372         if (!gpe_event_info) {
 373                 /*
 374                  * This gpe_number is not valid for this GPE block, just ignore it.
 375                  * However, it may be valid for a different GPE block, since GPE0
 376                  * and GPE1 methods both appear under \_GPE.
 377                  */
 378                 return_ACPI_STATUS(AE_OK);
 379         }
 380
 381         if ((ACPI_GPE_DISPATCH_TYPE(gpe_event_info->flags) ==
 382              ACPI_GPE_DISPATCH_HANDLER) ||
 383             (ACPI_GPE_DISPATCH_TYPE(gpe_event_info->flags) ==
 384              ACPI_GPE_DISPATCH_RAW_HANDLER)) {
 385
 386                 /* If there is already a handler, ignore this GPE method */
 387
 388                 return_ACPI_STATUS(AE_OK);
 389         }
 390
 391         if (ACPI_GPE_DISPATCH_TYPE(gpe_event_info->flags) ==
 392             ACPI_GPE_DISPATCH_METHOD) {
 393                 /*
 394                  * If there is already a method, ignore this method. But check
 395                  * for a type mismatch (if both the _Lxx AND _Exx exist)
 396                  */
 397                 if (type != (gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK)) {
 398                         ACPI_ERROR((AE_INFO,
 399                                     "For GPE 0x%.2X, found both _L%2.2X and _E%2.2X methods",
 400                                     gpe_number, gpe_number, gpe_number));
 401                 }
 402                 return_ACPI_STATUS(AE_OK);
 403         }
 404
 405         /* Disable the GPE in case it's been enabled already. */
 406
 407         (void)acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_DISABLE);
 408
 409         /*
 410          * Add the GPE information from above to the gpe_event_info block for
 411          * use during dispatch of this GPE.
 412          */
 413         gpe_event_info->flags &= ~(ACPI_GPE_DISPATCH_MASK);
 414         gpe_event_info->flags |= (u8)(type | ACPI_GPE_DISPATCH_METHOD);
 415         gpe_event_info->dispatch.method_node = method_node;
 416
 417         ACPI_DEBUG_PRINT((ACPI_DB_LOAD,
 418                           "Registered GPE method %s as GPE number 0x%.2X\n",
 419                           name, gpe_number));
 420         return_ACPI_STATUS(AE_OK);
 421 }
 422
 423 #endif                          /* !ACPI_REDUCED_HARDWARE */