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