LXR linux/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
  16ACPI_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 ******************************************************************************/
  56acpi_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
 184cleanup:
 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
 203void 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
 291acpi_status
 292acpi_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 */
 424