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_mask
  58  *
  59  * PARAMETERS:  gpe_event_info          - GPE to update
  60  *
  61  * RETURN:      Status
  62  *
  63  * DESCRIPTION: Updates GPE register enable mask based upon whether there are
  64  *              runtime references to this GPE
  65  *
  66  ******************************************************************************/
  67
  68 acpi_status
  69 acpi_ev_update_gpe_enable_mask(struct acpi_gpe_event_info *gpe_event_info)
  70 {
  71         struct acpi_gpe_register_info *gpe_register_info;
  72         u32 register_bit;
  73
  74         ACPI_FUNCTION_TRACE(ev_update_gpe_enable_mask);
  75
  76         gpe_register_info = gpe_event_info->register_info;
  77         if (!gpe_register_info) {
  78                 return_ACPI_STATUS(AE_NOT_EXIST);
  79         }
  80
  81         register_bit = acpi_hw_get_gpe_register_bit(gpe_event_info,
  82                                                 gpe_register_info);
  83
  84         /* Clear the run bit up front */
  85
  86         ACPI_CLEAR_BIT(gpe_register_info->enable_for_run, register_bit);
  87
  88         /* Set the mask bit only if there are references to this GPE */
  89
  90         if (gpe_event_info->runtime_count) {
  91                 ACPI_SET_BIT(gpe_register_info->enable_for_run, (u8)register_bit);
  92         }
  93
  94         return_ACPI_STATUS(AE_OK);
  95 }
  96
  97 /*******************************************************************************
  98  *
  99  * FUNCTION:    acpi_ev_enable_gpe
 100  *
 101  * PARAMETERS:  gpe_event_info  - GPE to enable
 102  *
 103  * RETURN:      Status
 104  *
 105  * DESCRIPTION: Clear the given GPE from stale events and enable it.
 106  *
 107  ******************************************************************************/
 108 acpi_status
 109 acpi_ev_enable_gpe(struct acpi_gpe_event_info *gpe_event_info)
 110 {
 111         acpi_status status;
 112
 113         ACPI_FUNCTION_TRACE(ev_enable_gpe);
 114
 115         /*
 116          * We will only allow a GPE to be enabled if it has either an
 117          * associated method (_Lxx/_Exx) or a handler. Otherwise, the
 118          * GPE will be immediately disabled by acpi_ev_gpe_dispatch the
 119          * first time it fires.
 120          */
 121         if (!(gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK)) {
 122                 return_ACPI_STATUS(AE_NO_HANDLER);
 123         }
 124
 125         /* Clear the GPE (of stale events) */
 126         status = acpi_hw_clear_gpe(gpe_event_info);
 127         if (ACPI_FAILURE(status)) {
 128                 return_ACPI_STATUS(status);
 129         }
 130
 131         /* Enable the requested GPE */
 132         status = acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_ENABLE);
 133
 134         return_ACPI_STATUS(status);
 135 }
 136
 137
 138 /*******************************************************************************
 139  *
 140  * FUNCTION:    acpi_ev_low_get_gpe_info
 141  *
 142  * PARAMETERS:  gpe_number          - Raw GPE number
 143  *              gpe_block           - A GPE info block
 144  *
 145  * RETURN:      A GPE event_info struct. NULL if not a valid GPE (The gpe_number
 146  *              is not within the specified GPE block)
 147  *
 148  * DESCRIPTION: Returns the event_info struct associated with this GPE. This is
 149  *              the low-level implementation of ev_get_gpe_event_info.
 150  *
 151  ******************************************************************************/
 152
 153 struct acpi_gpe_event_info *acpi_ev_low_get_gpe_info(u32 gpe_number,
 154                                                      struct acpi_gpe_block_info
 155                                                      *gpe_block)
 156 {
 157         u32 gpe_index;
 158
 159         /*
 160          * Validate that the gpe_number is within the specified gpe_block.
 161          * (Two steps)
 162          */
 163         if (!gpe_block || (gpe_number < gpe_block->block_base_number)) {
 164                 return (NULL);
 165         }
 166
 167         gpe_index = gpe_number - gpe_block->block_base_number;
 168         if (gpe_index >= gpe_block->gpe_count) {
 169                 return (NULL);
 170         }
 171
 172         return (&gpe_block->event_info[gpe_index]);
 173 }
 174
 175
 176 /*******************************************************************************
 177  *
 178  * FUNCTION:    acpi_ev_get_gpe_event_info
 179  *
 180  * PARAMETERS:  gpe_device          - Device node. NULL for GPE0/GPE1
 181  *              gpe_number          - Raw GPE number
 182  *
 183  * RETURN:      A GPE event_info struct. NULL if not a valid GPE
 184  *
 185  * DESCRIPTION: Returns the event_info struct associated with this GPE.
 186  *              Validates the gpe_block and the gpe_number
 187  *
 188  *              Should be called only when the GPE lists are semaphore locked
 189  *              and not subject to change.
 190  *
 191  ******************************************************************************/
 192
 193 struct acpi_gpe_event_info *acpi_ev_get_gpe_event_info(acpi_handle gpe_device,
 194                                                        u32 gpe_number)
 195 {
 196         union acpi_operand_object *obj_desc;
 197         struct acpi_gpe_event_info *gpe_info;
 198         u32 i;
 199
 200         ACPI_FUNCTION_ENTRY();
 201
 202         /* A NULL gpe_device means use the FADT-defined GPE block(s) */
 203
 204         if (!gpe_device) {
 205
 206                 /* Examine GPE Block 0 and 1 (These blocks are permanent) */
 207
 208                 for (i = 0; i < ACPI_MAX_GPE_BLOCKS; i++) {
 209                         gpe_info = acpi_ev_low_get_gpe_info(gpe_number,
 210                                                             acpi_gbl_gpe_fadt_blocks
 211                                                             [i]);
 212                         if (gpe_info) {
 213                                 return (gpe_info);
 214                         }
 215                 }
 216
 217                 /* The gpe_number was not in the range of either FADT GPE block */
 218
 219                 return (NULL);
 220         }
 221
 222         /* A Non-NULL gpe_device means this is a GPE Block Device */
 223
 224         obj_desc = acpi_ns_get_attached_object((struct acpi_namespace_node *)
 225                                                gpe_device);
 226         if (!obj_desc || !obj_desc->device.gpe_block) {
 227                 return (NULL);
 228         }
 229
 230         return (acpi_ev_low_get_gpe_info
 231                 (gpe_number, obj_desc->device.gpe_block));
 232 }
 233
 234 /*******************************************************************************
 235  *
 236  * FUNCTION:    acpi_ev_gpe_detect
 237  *
 238  * PARAMETERS:  gpe_xrupt_list      - Interrupt block for this interrupt.
 239  *                                    Can have multiple GPE blocks attached.
 240  *
 241  * RETURN:      INTERRUPT_HANDLED or INTERRUPT_NOT_HANDLED
 242  *
 243  * DESCRIPTION: Detect if any GP events have occurred. This function is
 244  *              executed at interrupt level.
 245  *
 246  ******************************************************************************/
 247
 248 u32 acpi_ev_gpe_detect(struct acpi_gpe_xrupt_info * gpe_xrupt_list)
 249 {
 250         acpi_status status;
 251         struct acpi_gpe_block_info *gpe_block;
 252         struct acpi_gpe_register_info *gpe_register_info;
 253         u32 int_status = ACPI_INTERRUPT_NOT_HANDLED;
 254         u8 enabled_status_byte;
 255         u32 status_reg;
 256         u32 enable_reg;
 257         acpi_cpu_flags flags;
 258         u32 i;
 259         u32 j;
 260
 261         ACPI_FUNCTION_NAME(ev_gpe_detect);
 262
 263         /* Check for the case where there are no GPEs */
 264
 265         if (!gpe_xrupt_list) {
 266                 return (int_status);
 267         }
 268
 269         /*
 270          * We need to obtain the GPE lock for both the data structs and registers
 271          * Note: Not necessary to obtain the hardware lock, since the GPE
 272          * registers are owned by the gpe_lock.
 273          */
 274         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
 275
 276         /* Examine all GPE blocks attached to this interrupt level */
 277
 278         gpe_block = gpe_xrupt_list->gpe_block_list_head;
 279         while (gpe_block) {
 280                 /*
 281                  * Read all of the 8-bit GPE status and enable registers in this GPE
 282                  * block, saving all of them. Find all currently active GP events.
 283                  */
 284                 for (i = 0; i < gpe_block->register_count; i++) {
 285
 286                         /* Get the next status/enable pair */
 287
 288                         gpe_register_info = &gpe_block->register_info[i];
 289
 290                         /* Read the Status Register */
 291
 292                         status =
 293                             acpi_hw_read(&status_reg,
 294                                          &gpe_register_info->status_address);
 295                         if (ACPI_FAILURE(status)) {
 296                                 goto unlock_and_exit;
 297                         }
 298
 299                         /* Read the Enable Register */
 300
 301                         status =
 302                             acpi_hw_read(&enable_reg,
 303                                          &gpe_register_info->enable_address);
 304                         if (ACPI_FAILURE(status)) {
 305                                 goto unlock_and_exit;
 306                         }
 307
 308                         ACPI_DEBUG_PRINT((ACPI_DB_INTERRUPTS,
 309                                           "Read GPE Register at GPE%X: Status=%02X, Enable=%02X\n",
 310                                           gpe_register_info->base_gpe_number,
 311                                           status_reg, enable_reg));
 312
 313                         /* Check if there is anything active at all in this register */
 314
 315                         enabled_status_byte = (u8) (status_reg & enable_reg);
 316                         if (!enabled_status_byte) {
 317
 318                                 /* No active GPEs in this register, move on */
 319
 320                                 continue;
 321                         }
 322
 323                         /* Now look at the individual GPEs in this byte register */
 324
 325                         for (j = 0; j < ACPI_GPE_REGISTER_WIDTH; j++) {
 326
 327                                 /* Examine one GPE bit */
 328
 329                                 if (enabled_status_byte & (1 << j)) {
 330                                         /*
 331                                          * Found an active GPE. Dispatch the event to a handler
 332                                          * or method.
 333                                          */
 334                                         int_status |=
 335                                             acpi_ev_gpe_dispatch(&gpe_block->
 336                                                 event_info[((acpi_size) i * ACPI_GPE_REGISTER_WIDTH) + j], j + gpe_register_info->base_gpe_number);
 337                                 }
 338                         }
 339                 }
 340
 341                 gpe_block = gpe_block->next;
 342         }
 343
 344       unlock_and_exit:
 345
 346         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
 347         return (int_status);
 348 }
 349
 350 /*******************************************************************************
 351  *
 352  * FUNCTION:    acpi_ev_asynch_execute_gpe_method
 353  *
 354  * PARAMETERS:  Context (gpe_event_info) - Info for this GPE
 355  *
 356  * RETURN:      None
 357  *
 358  * DESCRIPTION: Perform the actual execution of a GPE control method. This
 359  *              function is called from an invocation of acpi_os_execute and
 360  *              therefore does NOT execute at interrupt level - so that
 361  *              the control method itself is not executed in the context of
 362  *              an interrupt handler.
 363  *
 364  ******************************************************************************/
 365 static void acpi_ev_asynch_enable_gpe(void *context);
 366
 367 static void ACPI_SYSTEM_XFACE acpi_ev_asynch_execute_gpe_method(void *context)
 368 {
 369         struct acpi_gpe_event_info *gpe_event_info = (void *)context;
 370         acpi_status status;
 371         struct acpi_gpe_event_info local_gpe_event_info;
 372         struct acpi_evaluate_info *info;
 373
 374         ACPI_FUNCTION_TRACE(ev_asynch_execute_gpe_method);
 375
 376         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 377         if (ACPI_FAILURE(status)) {
 378                 return_VOID;
 379         }
 380
 381         /* Must revalidate the gpe_number/gpe_block */
 382
 383         if (!acpi_ev_valid_gpe_event(gpe_event_info)) {
 384                 status = acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 385                 return_VOID;
 386         }
 387
 388         /*
 389          * Take a snapshot of the GPE info for this level - we copy the info to
 390          * prevent a race condition with remove_handler/remove_block.
 391          */
 392         ACPI_MEMCPY(&local_gpe_event_info, gpe_event_info,
 393                     sizeof(struct acpi_gpe_event_info));
 394
 395         status = acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 396         if (ACPI_FAILURE(status)) {
 397                 return_VOID;
 398         }
 399
 400         /*
 401          * Must check for control method type dispatch one more time to avoid a
 402          * race with ev_gpe_install_handler
 403          */
 404         if ((local_gpe_event_info.flags & ACPI_GPE_DISPATCH_MASK) ==
 405             ACPI_GPE_DISPATCH_METHOD) {
 406
 407                 /* Allocate the evaluation information block */
 408
 409                 info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
 410                 if (!info) {
 411                         status = AE_NO_MEMORY;
 412                 } else {
 413                         /*
 414                          * Invoke the GPE Method (_Lxx, _Exx) i.e., evaluate the _Lxx/_Exx
 415                          * control method that corresponds to this GPE
 416                          */
 417                         info->prefix_node =
 418                             local_gpe_event_info.dispatch.method_node;
 419                         info->flags = ACPI_IGNORE_RETURN_VALUE;
 420
 421                         status = acpi_ns_evaluate(info);
 422                         ACPI_FREE(info);
 423                 }
 424
 425                 if (ACPI_FAILURE(status)) {
 426                         ACPI_EXCEPTION((AE_INFO, status,
 427                                         "while evaluating GPE method [%4.4s]",
 428                                         acpi_ut_get_node_name
 429                                         (local_gpe_event_info.dispatch.
 430                                          method_node)));
 431                 }
 432         }
 433         /* Defer enabling of GPE until all notify handlers are done */
 434         acpi_os_execute(OSL_NOTIFY_HANDLER, acpi_ev_asynch_enable_gpe,
 435                                 gpe_event_info);
 436         return_VOID;
 437 }
 438
 439 static void acpi_ev_asynch_enable_gpe(void *context)
 440 {
 441         struct acpi_gpe_event_info *gpe_event_info = context;
 442         acpi_status status;
 443         if ((gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
 444             ACPI_GPE_LEVEL_TRIGGERED) {
 445                 /*
 446                  * GPE is level-triggered, we clear the GPE status bit after handling
 447                  * the event.
 448                  */
 449                 status = acpi_hw_clear_gpe(gpe_event_info);
 450                 if (ACPI_FAILURE(status)) {
 451                         return_VOID;
 452                 }
 453         }
 454
 455         /*
 456          * Enable this GPE, conditionally. This means that the GPE will only be
 457          * physically enabled if the enable_for_run bit is set in the event_info
 458          */
 459         (void)acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_COND_ENABLE);
 460
 461         return_VOID;
 462 }
 463
 464 /*******************************************************************************
 465  *
 466  * FUNCTION:    acpi_ev_gpe_dispatch
 467  *
 468  * PARAMETERS:  gpe_event_info  - Info for this GPE
 469  *              gpe_number      - Number relative to the parent GPE block
 470  *
 471  * RETURN:      INTERRUPT_HANDLED or INTERRUPT_NOT_HANDLED
 472  *
 473  * DESCRIPTION: Dispatch a General Purpose Event to either a function (e.g. EC)
 474  *              or method (e.g. _Lxx/_Exx) handler.
 475  *
 476  *              This function executes at interrupt level.
 477  *
 478  ******************************************************************************/
 479
 480 u32
 481 acpi_ev_gpe_dispatch(struct acpi_gpe_event_info *gpe_event_info, u32 gpe_number)
 482 {
 483         acpi_status status;
 484
 485         ACPI_FUNCTION_TRACE(ev_gpe_dispatch);
 486
 487         acpi_os_gpe_count(gpe_number);
 488
 489         /*
 490          * If edge-triggered, clear the GPE status bit now. Note that
 491          * level-triggered events are cleared after the GPE is serviced.
 492          */
 493         if ((gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
 494             ACPI_GPE_EDGE_TRIGGERED) {
 495                 status = acpi_hw_clear_gpe(gpe_event_info);
 496                 if (ACPI_FAILURE(status)) {
 497                         ACPI_EXCEPTION((AE_INFO, status,
 498                                         "Unable to clear GPE[0x%2X]",
 499                                         gpe_number));
 500                         return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
 501                 }
 502         }
 503
 504         /*
 505          * Dispatch the GPE to either an installed handler, or the control method
 506          * associated with this GPE (_Lxx or _Exx). If a handler exists, we invoke
 507          * it and do not attempt to run the method. If there is neither a handler
 508          * nor a method, we disable this GPE to prevent further such pointless
 509          * events from firing.
 510          */
 511         switch (gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) {
 512         case ACPI_GPE_DISPATCH_HANDLER:
 513
 514                 /*
 515                  * Invoke the installed handler (at interrupt level)
 516                  * Ignore return status for now.
 517                  * TBD: leave GPE disabled on error?
 518                  */
 519                 (void)gpe_event_info->dispatch.handler->address(gpe_event_info->
 520                                                                 dispatch.
 521                                                                 handler->
 522                                                                 context);
 523
 524                 /* It is now safe to clear level-triggered events. */
 525
 526                 if ((gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
 527                     ACPI_GPE_LEVEL_TRIGGERED) {
 528                         status = acpi_hw_clear_gpe(gpe_event_info);
 529                         if (ACPI_FAILURE(status)) {
 530                                 ACPI_EXCEPTION((AE_INFO, status,
 531                                         "Unable to clear GPE[0x%2X]",
 532                                                 gpe_number));
 533                                 return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
 534                         }
 535                 }
 536                 break;
 537
 538         case ACPI_GPE_DISPATCH_METHOD:
 539
 540                 /*
 541                  * Disable the GPE, so it doesn't keep firing before the method has a
 542                  * chance to run (it runs asynchronously with interrupts enabled).
 543                  */
 544                 status = acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_DISABLE);
 545                 if (ACPI_FAILURE(status)) {
 546                         ACPI_EXCEPTION((AE_INFO, status,
 547                                         "Unable to disable GPE[0x%2X]",
 548                                         gpe_number));
 549                         return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
 550                 }
 551
 552                 /*
 553                  * Execute the method associated with the GPE
 554                  * NOTE: Level-triggered GPEs are cleared after the method completes.
 555                  */
 556                 status = acpi_os_execute(OSL_GPE_HANDLER,
 557                                          acpi_ev_asynch_execute_gpe_method,
 558                                          gpe_event_info);
 559                 if (ACPI_FAILURE(status)) {
 560                         ACPI_EXCEPTION((AE_INFO, status,
 561                                         "Unable to queue handler for GPE[0x%2X] - event disabled",
 562                                         gpe_number));
 563                 }
 564                 break;
 565
 566         default:
 567
 568                 /*
 569                  * No handler or method to run!
 570                  * 03/2010: This case should no longer be possible. We will not allow
 571                  * a GPE to be enabled if it has no handler or method.
 572                  */
 573                 ACPI_ERROR((AE_INFO,
 574                             "No handler or method for GPE[0x%2X], disabling event",
 575                             gpe_number));
 576
 577                 /*
 578                  * Disable the GPE. The GPE will remain disabled a handler
 579                  * is installed or ACPICA is restarted.
 580                  */
 581                 status = acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_DISABLE);
 582                 if (ACPI_FAILURE(status)) {
 583                         ACPI_EXCEPTION((AE_INFO, status,
 584                                         "Unable to disable GPE[0x%2X]",
 585                                         gpe_number));
 586                         return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
 587                 }
 588                 break;
 589         }
 590
 591         return_UINT32(ACPI_INTERRUPT_HANDLED);
 592 }