drivers/acpi/acpica/evgpe.c

   1 /******************************************************************************
   2  *
   3  * Module Name: evgpe - General Purpose Event handling and dispatch
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2010, 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("evgpe")
  51
  52 /* Local prototypes */
  53 static void ACPI_SYSTEM_XFACE acpi_ev_asynch_execute_gpe_method(void *context);
  54
  55 /*******************************************************************************
  56  *
  57  * FUNCTION:    acpi_ev_update_gpe_enable_masks
  58  *
  59  * PARAMETERS:  gpe_event_info          - GPE to update
  60  *
  61  * RETURN:      Status
  62  *
  63  * DESCRIPTION: Updates GPE register enable masks based on the GPE type
  64  *
  65  ******************************************************************************/
  66
  67 acpi_status
  68 acpi_ev_update_gpe_enable_masks(struct acpi_gpe_event_info *gpe_event_info)
  69 {
  70         struct acpi_gpe_register_info *gpe_register_info;
  71         u8 register_bit;
  72
  73         ACPI_FUNCTION_TRACE(ev_update_gpe_enable_masks);
  74
  75         gpe_register_info = gpe_event_info->register_info;
  76         if (!gpe_register_info) {
  77                 return_ACPI_STATUS(AE_NOT_EXIST);
  78         }
  79
  80         register_bit = (u8)
  81             (1 <<
  82              (gpe_event_info->gpe_number - gpe_register_info->base_gpe_number));
  83
  84         ACPI_CLEAR_BIT(gpe_register_info->enable_for_wake, register_bit);
  85         ACPI_CLEAR_BIT(gpe_register_info->enable_for_run, register_bit);
  86
  87         if (gpe_event_info->runtime_count)
  88                 ACPI_SET_BIT(gpe_register_info->enable_for_run, register_bit);
  89
  90         if (gpe_event_info->wakeup_count)
  91                 ACPI_SET_BIT(gpe_register_info->enable_for_wake, register_bit);
  92
  93         return_ACPI_STATUS(AE_OK);
  94 }
  95
  96 /*******************************************************************************
  97  *
  98  * FUNCTION:    acpi_ev_enable_gpe
  99  *
 100  * PARAMETERS:  gpe_event_info          - GPE to enable
 101  *
 102  * RETURN:      Status
 103  *
 104  * DESCRIPTION: Enable a GPE based on the GPE type
 105  *
 106  ******************************************************************************/
 107
 108 acpi_status acpi_ev_enable_gpe(struct acpi_gpe_event_info *gpe_event_info)
 109 {
 110         acpi_status status;
 111
 112         ACPI_FUNCTION_TRACE(ev_enable_gpe);
 113
 114         /* Make sure HW enable masks are updated */
 115
 116         status = acpi_ev_update_gpe_enable_masks(gpe_event_info);
 117         if (ACPI_FAILURE(status))
 118                 return_ACPI_STATUS(status);
 119
 120         /* Clear the GPE (of stale events), then enable it */
 121         status = acpi_hw_clear_gpe(gpe_event_info);
 122         if (ACPI_FAILURE(status))
 123                 return_ACPI_STATUS(status);
 124
 125         /* Enable the requested GPE */
 126         status = acpi_hw_write_gpe_enable_reg(gpe_event_info);
 127         return_ACPI_STATUS(status);
 128 }
 129
 130 /*******************************************************************************
 131  *
 132  * FUNCTION:    acpi_ev_disable_gpe
 133  *
 134  * PARAMETERS:  gpe_event_info          - GPE to disable
 135  *
 136  * RETURN:      Status
 137  *
 138  * DESCRIPTION: Disable a GPE based on the GPE type
 139  *
 140  ******************************************************************************/
 141
 142 acpi_status acpi_ev_disable_gpe(struct acpi_gpe_event_info *gpe_event_info)
 143 {
 144         acpi_status status;
 145
 146         ACPI_FUNCTION_TRACE(ev_disable_gpe);
 147
 148         /* Make sure HW enable masks are updated */
 149
 150         status = acpi_ev_update_gpe_enable_masks(gpe_event_info);
 151         if (ACPI_FAILURE(status))
 152                 return_ACPI_STATUS(status);
 153
 154         /*
 155          * Even if we don't know the GPE type, make sure that we always
 156          * disable it. low_disable_gpe will just clear the enable bit for this
 157          * GPE and write it. It will not write out the current GPE enable mask,
 158          * since this may inadvertently enable GPEs too early, if a rogue GPE has
 159          * come in during ACPICA initialization - possibly as a result of AML or
 160          * other code that has enabled the GPE.
 161          */
 162         status = acpi_hw_low_disable_gpe(gpe_event_info);
 163         return_ACPI_STATUS(status);
 164 }
 165
 166 /*******************************************************************************
 167  *
 168  * FUNCTION:    acpi_ev_get_gpe_event_info
 169  *
 170  * PARAMETERS:  gpe_device          - Device node. NULL for GPE0/GPE1
 171  *              gpe_number          - Raw GPE number
 172  *
 173  * RETURN:      A GPE event_info struct. NULL if not a valid GPE
 174  *
 175  * DESCRIPTION: Returns the event_info struct associated with this GPE.
 176  *              Validates the gpe_block and the gpe_number
 177  *
 178  *              Should be called only when the GPE lists are semaphore locked
 179  *              and not subject to change.
 180  *
 181  ******************************************************************************/
 182
 183 struct acpi_gpe_event_info *acpi_ev_get_gpe_event_info(acpi_handle gpe_device,
 184                                                        u32 gpe_number)
 185 {
 186         union acpi_operand_object *obj_desc;
 187         struct acpi_gpe_block_info *gpe_block;
 188         u32 i;
 189
 190         ACPI_FUNCTION_ENTRY();
 191
 192         /* A NULL gpe_block means use the FADT-defined GPE block(s) */
 193
 194         if (!gpe_device) {
 195
 196                 /* Examine GPE Block 0 and 1 (These blocks are permanent) */
 197
 198                 for (i = 0; i < ACPI_MAX_GPE_BLOCKS; i++) {
 199                         gpe_block = acpi_gbl_gpe_fadt_blocks[i];
 200                         if (gpe_block) {
 201                                 if ((gpe_number >= gpe_block->block_base_number)
 202                                     && (gpe_number <
 203                                         gpe_block->block_base_number +
 204                                         (gpe_block->register_count * 8))) {
 205                                         return (&gpe_block->
 206                                                 event_info[gpe_number -
 207                                                            gpe_block->
 208                                                            block_base_number]);
 209                                 }
 210                         }
 211                 }
 212
 213                 /* The gpe_number was not in the range of either FADT GPE block */
 214
 215                 return (NULL);
 216         }
 217
 218         /* A Non-NULL gpe_device means this is a GPE Block Device */
 219
 220         obj_desc = acpi_ns_get_attached_object((struct acpi_namespace_node *)
 221                                                gpe_device);
 222         if (!obj_desc || !obj_desc->device.gpe_block) {
 223                 return (NULL);
 224         }
 225
 226         gpe_block = obj_desc->device.gpe_block;
 227
 228         if ((gpe_number >= gpe_block->block_base_number) &&
 229             (gpe_number <
 230              gpe_block->block_base_number + (gpe_block->register_count * 8))) {
 231                 return (&gpe_block->
 232                         event_info[gpe_number - gpe_block->block_base_number]);
 233         }
 234
 235         return (NULL);
 236 }
 237
 238 /*******************************************************************************
 239  *
 240  * FUNCTION:    acpi_ev_gpe_detect
 241  *
 242  * PARAMETERS:  gpe_xrupt_list      - Interrupt block for this interrupt.
 243  *                                    Can have multiple GPE blocks attached.
 244  *
 245  * RETURN:      INTERRUPT_HANDLED or INTERRUPT_NOT_HANDLED
 246  *
 247  * DESCRIPTION: Detect if any GP events have occurred. This function is
 248  *              executed at interrupt level.
 249  *
 250  ******************************************************************************/
 251
 252 u32 acpi_ev_gpe_detect(struct acpi_gpe_xrupt_info * gpe_xrupt_list)
 253 {
 254         acpi_status status;
 255         struct acpi_gpe_block_info *gpe_block;
 256         struct acpi_gpe_register_info *gpe_register_info;
 257         u32 int_status = ACPI_INTERRUPT_NOT_HANDLED;
 258         u8 enabled_status_byte;
 259         u32 status_reg;
 260         u32 enable_reg;
 261         acpi_cpu_flags flags;
 262         u32 i;
 263         u32 j;
 264
 265         ACPI_FUNCTION_NAME(ev_gpe_detect);
 266
 267         /* Check for the case where there are no GPEs */
 268
 269         if (!gpe_xrupt_list) {
 270                 return (int_status);
 271         }
 272
 273         /*
 274          * We need to obtain the GPE lock for both the data structs and registers
 275          * Note: Not necessary to obtain the hardware lock, since the GPE
 276          * registers are owned by the gpe_lock.
 277          */
 278         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
 279
 280         /* Examine all GPE blocks attached to this interrupt level */
 281
 282         gpe_block = gpe_xrupt_list->gpe_block_list_head;
 283         while (gpe_block) {
 284                 /*
 285                  * Read all of the 8-bit GPE status and enable registers in this GPE
 286                  * block, saving all of them. Find all currently active GP events.
 287                  */
 288                 for (i = 0; i < gpe_block->register_count; i++) {
 289
 290                         /* Get the next status/enable pair */
 291
 292                         gpe_register_info = &gpe_block->register_info[i];
 293
 294                         /* Read the Status Register */
 295
 296                         status =
 297                             acpi_hw_read(&status_reg,
 298                                          &gpe_register_info->status_address);
 299                         if (ACPI_FAILURE(status)) {
 300                                 goto unlock_and_exit;
 301                         }
 302
 303                         /* Read the Enable Register */
 304
 305                         status =
 306                             acpi_hw_read(&enable_reg,
 307                                          &gpe_register_info->enable_address);
 308                         if (ACPI_FAILURE(status)) {
 309                                 goto unlock_and_exit;
 310                         }
 311
 312                         ACPI_DEBUG_PRINT((ACPI_DB_INTERRUPTS,
 313                                           "Read GPE Register at GPE%X: Status=%02X, Enable=%02X\n",
 314                                           gpe_register_info->base_gpe_number,
 315                                           status_reg, enable_reg));
 316
 317                         /* Check if there is anything active at all in this register */
 318
 319                         enabled_status_byte = (u8) (status_reg & enable_reg);
 320                         if (!enabled_status_byte) {
 321
 322                                 /* No active GPEs in this register, move on */
 323
 324                                 continue;
 325                         }
 326
 327                         /* Now look at the individual GPEs in this byte register */
 328
 329                         for (j = 0; j < ACPI_GPE_REGISTER_WIDTH; j++) {
 330
 331                                 /* Examine one GPE bit */
 332
 333                                 if (enabled_status_byte & (1 << j)) {
 334                                         /*
 335                                          * Found an active GPE. Dispatch the event to a handler
 336                                          * or method.
 337                                          */
 338                                         int_status |=
 339                                             acpi_ev_gpe_dispatch(&gpe_block->
 340                                                 event_info[((acpi_size) i * ACPI_GPE_REGISTER_WIDTH) + j], j + gpe_register_info->base_gpe_number);
 341                                 }
 342                         }
 343                 }
 344
 345                 gpe_block = gpe_block->next;
 346         }
 347
 348       unlock_and_exit:
 349
 350         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
 351         return (int_status);
 352 }
 353
 354 /*******************************************************************************
 355  *
 356  * FUNCTION:    acpi_ev_asynch_execute_gpe_method
 357  *
 358  * PARAMETERS:  Context (gpe_event_info) - Info for this GPE
 359  *
 360  * RETURN:      None
 361  *
 362  * DESCRIPTION: Perform the actual execution of a GPE control method. This
 363  *              function is called from an invocation of acpi_os_execute and
 364  *              therefore does NOT execute at interrupt level - so that
 365  *              the control method itself is not executed in the context of
 366  *              an interrupt handler.
 367  *
 368  ******************************************************************************/
 369 static void acpi_ev_asynch_enable_gpe(void *context);
 370
 371 static void ACPI_SYSTEM_XFACE acpi_ev_asynch_execute_gpe_method(void *context)
 372 {
 373         struct acpi_gpe_event_info *gpe_event_info = (void *)context;
 374         acpi_status status;
 375         struct acpi_gpe_event_info local_gpe_event_info;
 376         struct acpi_evaluate_info *info;
 377
 378         ACPI_FUNCTION_TRACE(ev_asynch_execute_gpe_method);
 379
 380         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 381         if (ACPI_FAILURE(status)) {
 382                 return_VOID;
 383         }
 384
 385         /* Must revalidate the gpe_number/gpe_block */
 386
 387         if (!acpi_ev_valid_gpe_event(gpe_event_info)) {
 388                 status = acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 389                 return_VOID;
 390         }
 391
 392         /* Set the GPE flags for return to enabled state */
 393
 394         (void)acpi_ev_update_gpe_enable_masks(gpe_event_info);
 395
 396         /*
 397          * Take a snapshot of the GPE info for this level - we copy the info to
 398          * prevent a race condition with remove_handler/remove_block.
 399          */
 400         ACPI_MEMCPY(&local_gpe_event_info, gpe_event_info,
 401                     sizeof(struct acpi_gpe_event_info));
 402
 403         status = acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 404         if (ACPI_FAILURE(status)) {
 405                 return_VOID;
 406         }
 407
 408         /*
 409          * Must check for control method type dispatch one more time to avoid a
 410          * race with ev_gpe_install_handler
 411          */
 412         if ((local_gpe_event_info.flags & ACPI_GPE_DISPATCH_MASK) ==
 413             ACPI_GPE_DISPATCH_METHOD) {
 414
 415                 /* Allocate the evaluation information block */
 416
 417                 info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
 418                 if (!info) {
 419                         status = AE_NO_MEMORY;
 420                 } else {
 421                         /*
 422                          * Invoke the GPE Method (_Lxx, _Exx) i.e., evaluate the _Lxx/_Exx
 423                          * control method that corresponds to this GPE
 424                          */
 425                         info->prefix_node =
 426                             local_gpe_event_info.dispatch.method_node;
 427                         info->flags = ACPI_IGNORE_RETURN_VALUE;
 428
 429                         status = acpi_ns_evaluate(info);
 430                         ACPI_FREE(info);
 431                 }
 432
 433                 if (ACPI_FAILURE(status)) {
 434                         ACPI_EXCEPTION((AE_INFO, status,
 435                                         "while evaluating GPE method [%4.4s]",
 436                                         acpi_ut_get_node_name
 437                                         (local_gpe_event_info.dispatch.
 438                                          method_node)));
 439                 }
 440         }
 441         /* Defer enabling of GPE until all notify handlers are done */
 442         acpi_os_execute(OSL_NOTIFY_HANDLER, acpi_ev_asynch_enable_gpe,
 443                                 gpe_event_info);
 444         return_VOID;
 445 }
 446
 447 static void acpi_ev_asynch_enable_gpe(void *context)
 448 {
 449         struct acpi_gpe_event_info *gpe_event_info = context;
 450         acpi_status status;
 451         if ((gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
 452             ACPI_GPE_LEVEL_TRIGGERED) {
 453                 /*
 454                  * GPE is level-triggered, we clear the GPE status bit after handling
 455                  * the event.
 456                  */
 457                 status = acpi_hw_clear_gpe(gpe_event_info);
 458                 if (ACPI_FAILURE(status)) {
 459                         return_VOID;
 460                 }
 461         }
 462
 463         /* Enable this GPE */
 464         (void)acpi_hw_write_gpe_enable_reg(gpe_event_info);
 465         return_VOID;
 466 }
 467
 468 /*******************************************************************************
 469  *
 470  * FUNCTION:    acpi_ev_gpe_dispatch
 471  *
 472  * PARAMETERS:  gpe_event_info  - Info for this GPE
 473  *              gpe_number      - Number relative to the parent GPE block
 474  *
 475  * RETURN:      INTERRUPT_HANDLED or INTERRUPT_NOT_HANDLED
 476  *
 477  * DESCRIPTION: Dispatch a General Purpose Event to either a function (e.g. EC)
 478  *              or method (e.g. _Lxx/_Exx) handler.
 479  *
 480  *              This function executes at interrupt level.
 481  *
 482  ******************************************************************************/
 483
 484 u32
 485 acpi_ev_gpe_dispatch(struct acpi_gpe_event_info *gpe_event_info, u32 gpe_number)
 486 {
 487         acpi_status status;
 488
 489         ACPI_FUNCTION_TRACE(ev_gpe_dispatch);
 490
 491         acpi_os_gpe_count(gpe_number);
 492
 493         /*
 494          * If edge-triggered, clear the GPE status bit now. Note that
 495          * level-triggered events are cleared after the GPE is serviced.
 496          */
 497         if ((gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
 498             ACPI_GPE_EDGE_TRIGGERED) {
 499                 status = acpi_hw_clear_gpe(gpe_event_info);
 500                 if (ACPI_FAILURE(status)) {
 501                         ACPI_EXCEPTION((AE_INFO, status,
 502                                         "Unable to clear GPE[%2X]",
 503                                         gpe_number));
 504                         return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
 505                 }
 506         }
 507
 508         /*
 509          * Dispatch the GPE to either an installed handler, or the control method
 510          * associated with this GPE (_Lxx or _Exx). If a handler exists, we invoke
 511          * it and do not attempt to run the method. If there is neither a handler
 512          * nor a method, we disable this GPE to prevent further such pointless
 513          * events from firing.
 514          */
 515         switch (gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) {
 516         case ACPI_GPE_DISPATCH_HANDLER:
 517
 518                 /*
 519                  * Invoke the installed handler (at interrupt level)
 520                  * Ignore return status for now.
 521                  * TBD: leave GPE disabled on error?
 522                  */
 523                 (void)gpe_event_info->dispatch.handler->address(gpe_event_info->
 524                                                                 dispatch.
 525                                                                 handler->
 526                                                                 context);
 527
 528                 /* It is now safe to clear level-triggered events. */
 529
 530                 if ((gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
 531                     ACPI_GPE_LEVEL_TRIGGERED) {
 532                         status = acpi_hw_clear_gpe(gpe_event_info);
 533                         if (ACPI_FAILURE(status)) {
 534                                 ACPI_EXCEPTION((AE_INFO, status,
 535                                                 "Unable to clear GPE[%2X]",
 536                                                 gpe_number));
 537                                 return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
 538                         }
 539                 }
 540                 break;
 541
 542         case ACPI_GPE_DISPATCH_METHOD:
 543
 544                 /*
 545                  * Disable the GPE, so it doesn't keep firing before the method has a
 546                  * chance to run (it runs asynchronously with interrupts enabled).
 547                  */
 548                 status = acpi_ev_disable_gpe(gpe_event_info);
 549                 if (ACPI_FAILURE(status)) {
 550                         ACPI_EXCEPTION((AE_INFO, status,
 551                                         "Unable to disable GPE[%2X]",
 552                                         gpe_number));
 553                         return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
 554                 }
 555
 556                 /*
 557                  * Execute the method associated with the GPE
 558                  * NOTE: Level-triggered GPEs are cleared after the method completes.
 559                  */
 560                 status = acpi_os_execute(OSL_GPE_HANDLER,
 561                                          acpi_ev_asynch_execute_gpe_method,
 562                                          gpe_event_info);
 563                 if (ACPI_FAILURE(status)) {
 564                         ACPI_EXCEPTION((AE_INFO, status,
 565                                         "Unable to queue handler for GPE[%2X] - event disabled",
 566                                         gpe_number));
 567                 }
 568                 break;
 569
 570         default:
 571
 572                 /* No handler or method to run! */
 573
 574                 ACPI_ERROR((AE_INFO,
 575                             "No handler or method for GPE[%2X], disabling event",
 576                             gpe_number));
 577
 578                 /*
 579                  * Disable the GPE. The GPE will remain disabled until the ACPICA
 580                  * Core Subsystem is restarted, or a handler is installed.
 581                  */
 582                 status = acpi_ev_disable_gpe(gpe_event_info);
 583                 if (ACPI_FAILURE(status)) {
 584                         ACPI_EXCEPTION((AE_INFO, status,
 585                                         "Unable to disable GPE[%2X]",
 586                                         gpe_number));
 587                         return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
 588                 }
 589                 break;
 590         }
 591
 592         return_UINT32(ACPI_INTERRUPT_HANDLED);
 593 }