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 - 2008, 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  *              write_to_hardware       - Enable now, or just mark data structs
 102  *                                        (WAKE GPEs should be deferred)
 103  *
 104  * RETURN:      Status
 105  *
 106  * DESCRIPTION: Enable a GPE based on the GPE type
 107  *
 108  ******************************************************************************/
 109
 110 acpi_status
 111 acpi_ev_enable_gpe(struct acpi_gpe_event_info *gpe_event_info,
 112                    u8 write_to_hardware)
 113 {
 114         acpi_status status;
 115
 116         ACPI_FUNCTION_TRACE(ev_enable_gpe);
 117
 118         /* Make sure HW enable masks are updated */
 119
 120         status = acpi_ev_update_gpe_enable_masks(gpe_event_info);
 121         if (ACPI_FAILURE(status))
 122                 return_ACPI_STATUS(status);
 123
 124         /* Mark wake-enabled or HW enable, or both */
 125
 126         if (gpe_event_info->runtime_count && write_to_hardware) {
 127                 /* Clear the GPE (of stale events), then enable it */
 128                 status = acpi_hw_clear_gpe(gpe_event_info);
 129                 if (ACPI_FAILURE(status))
 130                         return_ACPI_STATUS(status);
 131
 132                 /* Enable the requested runtime GPE */
 133                 status = acpi_hw_write_gpe_enable_reg(gpe_event_info);
 134         }
 135
 136         return_ACPI_STATUS(AE_OK);
 137 }
 138
 139 /*******************************************************************************
 140  *
 141  * FUNCTION:    acpi_ev_disable_gpe
 142  *
 143  * PARAMETERS:  gpe_event_info          - GPE to disable
 144  *
 145  * RETURN:      Status
 146  *
 147  * DESCRIPTION: Disable a GPE based on the GPE type
 148  *
 149  ******************************************************************************/
 150
 151 acpi_status acpi_ev_disable_gpe(struct acpi_gpe_event_info *gpe_event_info)
 152 {
 153         acpi_status status;
 154
 155         ACPI_FUNCTION_TRACE(ev_disable_gpe);
 156
 157         /* Make sure HW enable masks are updated */
 158
 159         status = acpi_ev_update_gpe_enable_masks(gpe_event_info);
 160         if (ACPI_FAILURE(status))
 161                 return_ACPI_STATUS(status);
 162
 163         /*
 164          * Even if we don't know the GPE type, make sure that we always
 165          * disable it. low_disable_gpe will just clear the enable bit for this
 166          * GPE and write it. It will not write out the current GPE enable mask,
 167          * since this may inadvertently enable GPEs too early, if a rogue GPE has
 168          * come in during ACPICA initialization - possibly as a result of AML or
 169          * other code that has enabled the GPE.
 170          */
 171         status = acpi_hw_low_disable_gpe(gpe_event_info);
 172         return_ACPI_STATUS(status);
 173 }
 174
 175 /*******************************************************************************
 176  *
 177  * FUNCTION:    acpi_ev_get_gpe_event_info
 178  *
 179  * PARAMETERS:  gpe_device          - Device node. NULL for GPE0/GPE1
 180  *              gpe_number          - Raw GPE number
 181  *
 182  * RETURN:      A GPE event_info struct. NULL if not a valid GPE
 183  *
 184  * DESCRIPTION: Returns the event_info struct associated with this GPE.
 185  *              Validates the gpe_block and the gpe_number
 186  *
 187  *              Should be called only when the GPE lists are semaphore locked
 188  *              and not subject to change.
 189  *
 190  ******************************************************************************/
 191
 192 struct acpi_gpe_event_info *acpi_ev_get_gpe_event_info(acpi_handle gpe_device,
 193                                                        u32 gpe_number)
 194 {
 195         union acpi_operand_object *obj_desc;
 196         struct acpi_gpe_block_info *gpe_block;
 197         u32 i;
 198
 199         ACPI_FUNCTION_ENTRY();
 200
 201         /* A NULL gpe_block means use the FADT-defined GPE block(s) */
 202
 203         if (!gpe_device) {
 204
 205                 /* Examine GPE Block 0 and 1 (These blocks are permanent) */
 206
 207                 for (i = 0; i < ACPI_MAX_GPE_BLOCKS; i++) {
 208                         gpe_block = acpi_gbl_gpe_fadt_blocks[i];
 209                         if (gpe_block) {
 210                                 if ((gpe_number >= gpe_block->block_base_number)
 211                                     && (gpe_number <
 212                                         gpe_block->block_base_number +
 213                                         (gpe_block->register_count * 8))) {
 214                                         return (&gpe_block->
 215                                                 event_info[gpe_number -
 216                                                            gpe_block->
 217                                                            block_base_number]);
 218                                 }
 219                         }
 220                 }
 221
 222                 /* The gpe_number was not in the range of either FADT GPE block */
 223
 224                 return (NULL);
 225         }
 226
 227         /* A Non-NULL gpe_device means this is a GPE Block Device */
 228
 229         obj_desc = acpi_ns_get_attached_object((struct acpi_namespace_node *)
 230                                                gpe_device);
 231         if (!obj_desc || !obj_desc->device.gpe_block) {
 232                 return (NULL);
 233         }
 234
 235         gpe_block = obj_desc->device.gpe_block;
 236
 237         if ((gpe_number >= gpe_block->block_base_number) &&
 238             (gpe_number <
 239              gpe_block->block_base_number + (gpe_block->register_count * 8))) {
 240                 return (&gpe_block->
 241                         event_info[gpe_number - gpe_block->block_base_number]);
 242         }
 243
 244         return (NULL);
 245 }
 246
 247 /*******************************************************************************
 248  *
 249  * FUNCTION:    acpi_ev_gpe_detect
 250  *
 251  * PARAMETERS:  gpe_xrupt_list      - Interrupt block for this interrupt.
 252  *                                    Can have multiple GPE blocks attached.
 253  *
 254  * RETURN:      INTERRUPT_HANDLED or INTERRUPT_NOT_HANDLED
 255  *
 256  * DESCRIPTION: Detect if any GP events have occurred. This function is
 257  *              executed at interrupt level.
 258  *
 259  ******************************************************************************/
 260
 261 u32 acpi_ev_gpe_detect(struct acpi_gpe_xrupt_info * gpe_xrupt_list)
 262 {
 263         acpi_status status;
 264         struct acpi_gpe_block_info *gpe_block;
 265         struct acpi_gpe_register_info *gpe_register_info;
 266         u32 int_status = ACPI_INTERRUPT_NOT_HANDLED;
 267         u8 enabled_status_byte;
 268         u32 status_reg;
 269         u32 enable_reg;
 270         acpi_cpu_flags flags;
 271         u32 i;
 272         u32 j;
 273
 274         ACPI_FUNCTION_NAME(ev_gpe_detect);
 275
 276         /* Check for the case where there are no GPEs */
 277
 278         if (!gpe_xrupt_list) {
 279                 return (int_status);
 280         }
 281
 282         /*
 283          * We need to obtain the GPE lock for both the data structs and registers
 284          * Note: Not necessary to obtain the hardware lock, since the GPE
 285          * registers are owned by the gpe_lock.
 286          */
 287         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
 288
 289         /* Examine all GPE blocks attached to this interrupt level */
 290
 291         gpe_block = gpe_xrupt_list->gpe_block_list_head;
 292         while (gpe_block) {
 293                 /*
 294                  * Read all of the 8-bit GPE status and enable registers in this GPE
 295                  * block, saving all of them. Find all currently active GP events.
 296                  */
 297                 for (i = 0; i < gpe_block->register_count; i++) {
 298
 299                         /* Get the next status/enable pair */
 300
 301                         gpe_register_info = &gpe_block->register_info[i];
 302
 303                         /* Read the Status Register */
 304
 305                         status =
 306                             acpi_hw_read(&status_reg,
 307                                          &gpe_register_info->status_address);
 308                         if (ACPI_FAILURE(status)) {
 309                                 goto unlock_and_exit;
 310                         }
 311
 312                         /* Read the Enable Register */
 313
 314                         status =
 315                             acpi_hw_read(&enable_reg,
 316                                          &gpe_register_info->enable_address);
 317                         if (ACPI_FAILURE(status)) {
 318                                 goto unlock_and_exit;
 319                         }
 320
 321                         ACPI_DEBUG_PRINT((ACPI_DB_INTERRUPTS,
 322                                           "Read GPE Register at GPE%X: Status=%02X, Enable=%02X\n",
 323                                           gpe_register_info->base_gpe_number,
 324                                           status_reg, enable_reg));
 325
 326                         /* Check if there is anything active at all in this register */
 327
 328                         enabled_status_byte = (u8) (status_reg & enable_reg);
 329                         if (!enabled_status_byte) {
 330
 331                                 /* No active GPEs in this register, move on */
 332
 333                                 continue;
 334                         }
 335
 336                         /* Now look at the individual GPEs in this byte register */
 337
 338                         for (j = 0; j < ACPI_GPE_REGISTER_WIDTH; j++) {
 339
 340                                 /* Examine one GPE bit */
 341
 342                                 if (enabled_status_byte & (1 << j)) {
 343                                         /*
 344                                          * Found an active GPE. Dispatch the event to a handler
 345                                          * or method.
 346                                          */
 347                                         int_status |=
 348                                             acpi_ev_gpe_dispatch(&gpe_block->
 349                                                 event_info[((acpi_size) i * ACPI_GPE_REGISTER_WIDTH) + j], j + gpe_register_info->base_gpe_number);
 350                                 }
 351                         }
 352                 }
 353
 354                 gpe_block = gpe_block->next;
 355         }
 356
 357       unlock_and_exit:
 358
 359         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
 360         return (int_status);
 361 }
 362
 363 /*******************************************************************************
 364  *
 365  * FUNCTION:    acpi_ev_asynch_execute_gpe_method
 366  *
 367  * PARAMETERS:  Context (gpe_event_info) - Info for this GPE
 368  *
 369  * RETURN:      None
 370  *
 371  * DESCRIPTION: Perform the actual execution of a GPE control method. This
 372  *              function is called from an invocation of acpi_os_execute and
 373  *              therefore does NOT execute at interrupt level - so that
 374  *              the control method itself is not executed in the context of
 375  *              an interrupt handler.
 376  *
 377  ******************************************************************************/
 378 static void acpi_ev_asynch_enable_gpe(void *context);
 379
 380 static void ACPI_SYSTEM_XFACE acpi_ev_asynch_execute_gpe_method(void *context)
 381 {
 382         struct acpi_gpe_event_info *gpe_event_info = (void *)context;
 383         acpi_status status;
 384         struct acpi_gpe_event_info local_gpe_event_info;
 385         struct acpi_evaluate_info *info;
 386
 387         ACPI_FUNCTION_TRACE(ev_asynch_execute_gpe_method);
 388
 389         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 390         if (ACPI_FAILURE(status)) {
 391                 return_VOID;
 392         }
 393
 394         /* Must revalidate the gpe_number/gpe_block */
 395
 396         if (!acpi_ev_valid_gpe_event(gpe_event_info)) {
 397                 status = acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 398                 return_VOID;
 399         }
 400
 401         /* Set the GPE flags for return to enabled state */
 402
 403         (void)acpi_ev_enable_gpe(gpe_event_info, FALSE);
 404
 405         /*
 406          * Take a snapshot of the GPE info for this level - we copy the info to
 407          * prevent a race condition with remove_handler/remove_block.
 408          */
 409         ACPI_MEMCPY(&local_gpe_event_info, gpe_event_info,
 410                     sizeof(struct acpi_gpe_event_info));
 411
 412         status = acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 413         if (ACPI_FAILURE(status)) {
 414                 return_VOID;
 415         }
 416
 417         /*
 418          * Must check for control method type dispatch one more time to avoid a
 419          * race with ev_gpe_install_handler
 420          */
 421         if ((local_gpe_event_info.flags & ACPI_GPE_DISPATCH_MASK) ==
 422             ACPI_GPE_DISPATCH_METHOD) {
 423
 424                 /* Allocate the evaluation information block */
 425
 426                 info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
 427                 if (!info) {
 428                         status = AE_NO_MEMORY;
 429                 } else {
 430                         /*
 431                          * Invoke the GPE Method (_Lxx, _Exx) i.e., evaluate the _Lxx/_Exx
 432                          * control method that corresponds to this GPE
 433                          */
 434                         info->prefix_node =
 435                             local_gpe_event_info.dispatch.method_node;
 436                         info->flags = ACPI_IGNORE_RETURN_VALUE;
 437
 438                         status = acpi_ns_evaluate(info);
 439                         ACPI_FREE(info);
 440                 }
 441
 442                 if (ACPI_FAILURE(status)) {
 443                         ACPI_EXCEPTION((AE_INFO, status,
 444                                         "while evaluating GPE method [%4.4s]",
 445                                         acpi_ut_get_node_name
 446                                         (local_gpe_event_info.dispatch.
 447                                          method_node)));
 448                 }
 449         }
 450         /* Defer enabling of GPE until all notify handlers are done */
 451         acpi_os_execute(OSL_NOTIFY_HANDLER, acpi_ev_asynch_enable_gpe,
 452                                 gpe_event_info);
 453         return_VOID;
 454 }
 455
 456 static void acpi_ev_asynch_enable_gpe(void *context)
 457 {
 458         struct acpi_gpe_event_info *gpe_event_info = context;
 459         acpi_status status;
 460         if ((gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
 461             ACPI_GPE_LEVEL_TRIGGERED) {
 462                 /*
 463                  * GPE is level-triggered, we clear the GPE status bit after handling
 464                  * the event.
 465                  */
 466                 status = acpi_hw_clear_gpe(gpe_event_info);
 467                 if (ACPI_FAILURE(status)) {
 468                         return_VOID;
 469                 }
 470         }
 471
 472         /* Enable this GPE */
 473         (void)acpi_hw_write_gpe_enable_reg(gpe_event_info);
 474         return_VOID;
 475 }
 476
 477 /*******************************************************************************
 478  *
 479  * FUNCTION:    acpi_ev_gpe_dispatch
 480  *
 481  * PARAMETERS:  gpe_event_info  - Info for this GPE
 482  *              gpe_number      - Number relative to the parent GPE block
 483  *
 484  * RETURN:      INTERRUPT_HANDLED or INTERRUPT_NOT_HANDLED
 485  *
 486  * DESCRIPTION: Dispatch a General Purpose Event to either a function (e.g. EC)
 487  *              or method (e.g. _Lxx/_Exx) handler.
 488  *
 489  *              This function executes at interrupt level.
 490  *
 491  ******************************************************************************/
 492
 493 u32
 494 acpi_ev_gpe_dispatch(struct acpi_gpe_event_info *gpe_event_info, u32 gpe_number)
 495 {
 496         acpi_status status;
 497
 498         ACPI_FUNCTION_TRACE(ev_gpe_dispatch);
 499
 500         acpi_os_gpe_count(gpe_number);
 501
 502         /*
 503          * If edge-triggered, clear the GPE status bit now. Note that
 504          * level-triggered events are cleared after the GPE is serviced.
 505          */
 506         if ((gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
 507             ACPI_GPE_EDGE_TRIGGERED) {
 508                 status = acpi_hw_clear_gpe(gpe_event_info);
 509                 if (ACPI_FAILURE(status)) {
 510                         ACPI_EXCEPTION((AE_INFO, status,
 511                                         "Unable to clear GPE[%2X]",
 512                                         gpe_number));
 513                         return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
 514                 }
 515         }
 516
 517         /*
 518          * Dispatch the GPE to either an installed handler, or the control method
 519          * associated with this GPE (_Lxx or _Exx). If a handler exists, we invoke
 520          * it and do not attempt to run the method. If there is neither a handler
 521          * nor a method, we disable this GPE to prevent further such pointless
 522          * events from firing.
 523          */
 524         switch (gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) {
 525         case ACPI_GPE_DISPATCH_HANDLER:
 526
 527                 /*
 528                  * Invoke the installed handler (at interrupt level)
 529                  * Ignore return status for now.
 530                  * TBD: leave GPE disabled on error?
 531                  */
 532                 (void)gpe_event_info->dispatch.handler->address(gpe_event_info->
 533                                                                 dispatch.
 534                                                                 handler->
 535                                                                 context);
 536
 537                 /* It is now safe to clear level-triggered events. */
 538
 539                 if ((gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
 540                     ACPI_GPE_LEVEL_TRIGGERED) {
 541                         status = acpi_hw_clear_gpe(gpe_event_info);
 542                         if (ACPI_FAILURE(status)) {
 543                                 ACPI_EXCEPTION((AE_INFO, status,
 544                                                 "Unable to clear GPE[%2X]",
 545                                                 gpe_number));
 546                                 return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
 547                         }
 548                 }
 549                 break;
 550
 551         case ACPI_GPE_DISPATCH_METHOD:
 552
 553                 /*
 554                  * Disable the GPE, so it doesn't keep firing before the method has a
 555                  * chance to run (it runs asynchronously with interrupts enabled).
 556                  */
 557                 status = acpi_ev_disable_gpe(gpe_event_info);
 558                 if (ACPI_FAILURE(status)) {
 559                         ACPI_EXCEPTION((AE_INFO, status,
 560                                         "Unable to disable GPE[%2X]",
 561                                         gpe_number));
 562                         return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
 563                 }
 564
 565                 /*
 566                  * Execute the method associated with the GPE
 567                  * NOTE: Level-triggered GPEs are cleared after the method completes.
 568                  */
 569                 status = acpi_os_execute(OSL_GPE_HANDLER,
 570                                          acpi_ev_asynch_execute_gpe_method,
 571                                          gpe_event_info);
 572                 if (ACPI_FAILURE(status)) {
 573                         ACPI_EXCEPTION((AE_INFO, status,
 574                                         "Unable to queue handler for GPE[%2X] - event disabled",
 575                                         gpe_number));
 576                 }
 577                 break;
 578
 579         default:
 580
 581                 /* No handler or method to run! */
 582
 583                 ACPI_ERROR((AE_INFO,
 584                             "No handler or method for GPE[%2X], disabling event",
 585                             gpe_number));
 586
 587                 /*
 588                  * Disable the GPE. The GPE will remain disabled until the ACPICA
 589                  * Core Subsystem is restarted, or a handler is installed.
 590                  */
 591                 status = acpi_ev_disable_gpe(gpe_event_info);
 592                 if (ACPI_FAILURE(status)) {
 593                         ACPI_EXCEPTION((AE_INFO, status,
 594                                         "Unable to disable GPE[%2X]",
 595                                         gpe_number));
 596                         return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
 597                 }
 598                 break;
 599         }
 600
 601         return_UINT32(ACPI_INTERRUPT_HANDLED);
 602 }