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 - 2019, 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/*******************************************************************************
  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 ******************************************************************************/
  46acpi_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
 173cleanup:
 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
 192void 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
 280acpi_status
 281acpi_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 */
 413