drivers/acpi/acpica/evregion.c

   1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
   2 /******************************************************************************
   3  *
   4  * Module Name: evregion - Operation Region support
   5  *
   6  * Copyright (C) 2000 - 2023, Intel Corp.
   7  *
   8  *****************************************************************************/
   9
  10 #include <acpi/acpi.h>
  11 #include "accommon.h"
  12 #include "acevents.h"
  13 #include "acnamesp.h"
  14 #include "acinterp.h"
  15
  16 #define _COMPONENT          ACPI_EVENTS
  17 ACPI_MODULE_NAME("evregion")
  18
  19 extern u8 acpi_gbl_default_address_spaces[];
  20
  21 /* Local prototypes */
  22
  23 static void
  24 acpi_ev_execute_orphan_reg_method(struct acpi_namespace_node *device_node,
  25                                   acpi_adr_space_type space_id);
  26
  27 static acpi_status
  28 acpi_ev_reg_run(acpi_handle obj_handle,
  29                 u32 level, void *context, void **return_value);
  30
  31 /*******************************************************************************
  32  *
  33  * FUNCTION:    acpi_ev_initialize_op_regions
  34  *
  35  * PARAMETERS:  None
  36  *
  37  * RETURN:      Status
  38  *
  39  * DESCRIPTION: Execute _REG methods for all Operation Regions that have
  40  *              an installed default region handler.
  41  *
  42  ******************************************************************************/
  43
  44 acpi_status acpi_ev_initialize_op_regions(void)
  45 {
  46         acpi_status status;
  47         u32 i;
  48
  49         ACPI_FUNCTION_TRACE(ev_initialize_op_regions);
  50
  51         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
  52         if (ACPI_FAILURE(status)) {
  53                 return_ACPI_STATUS(status);
  54         }
  55
  56         /* Run the _REG methods for op_regions in each default address space */
  57
  58         for (i = 0; i < ACPI_NUM_DEFAULT_SPACES; i++) {
  59                 /*
  60                  * Make sure the installed handler is the DEFAULT handler. If not the
  61                  * default, the _REG methods will have already been run (when the
  62                  * handler was installed)
  63                  */
  64                 if (acpi_ev_has_default_handler(acpi_gbl_root_node,
  65                                                 acpi_gbl_default_address_spaces
  66                                                 [i])) {
  67                         acpi_ev_execute_reg_methods(acpi_gbl_root_node,
  68                                                     acpi_gbl_default_address_spaces
  69                                                     [i], ACPI_REG_CONNECT);
  70                 }
  71         }
  72
  73         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
  74         return_ACPI_STATUS(status);
  75 }
  76
  77 /*******************************************************************************
  78  *
  79  * FUNCTION:    acpi_ev_address_space_dispatch
  80  *
  81  * PARAMETERS:  region_obj          - Internal region object
  82  *              field_obj           - Corresponding field. Can be NULL.
  83  *              function            - Read or Write operation
  84  *              region_offset       - Where in the region to read or write
  85  *              bit_width           - Field width in bits (8, 16, 32, or 64)
  86  *              value               - Pointer to in or out value, must be
  87  *                                    a full 64-bit integer
  88  *
  89  * RETURN:      Status
  90  *
  91  * DESCRIPTION: Dispatch an address space or operation region access to
  92  *              a previously installed handler.
  93  *
  94  * NOTE: During early initialization, we always install the default region
  95  * handlers for Memory, I/O and PCI_Config. This ensures that these operation
  96  * region address spaces are always available as per the ACPI specification.
  97  * This is especially needed in order to support the execution of
  98  * module-level AML code during loading of the ACPI tables.
  99  *
 100  ******************************************************************************/
 101
 102 acpi_status
 103 acpi_ev_address_space_dispatch(union acpi_operand_object *region_obj,
 104                                union acpi_operand_object *field_obj,
 105                                u32 function,
 106                                u32 region_offset, u32 bit_width, u64 *value)
 107 {
 108         acpi_status status;
 109         acpi_adr_space_handler handler;
 110         acpi_adr_space_setup region_setup;
 111         union acpi_operand_object *handler_desc;
 112         union acpi_operand_object *region_obj2;
 113         void *region_context = NULL;
 114         struct acpi_connection_info *context;
 115         acpi_mutex context_mutex;
 116         u8 context_locked;
 117         acpi_physical_address address;
 118
 119         ACPI_FUNCTION_TRACE(ev_address_space_dispatch);
 120
 121         region_obj2 = acpi_ns_get_secondary_object(region_obj);
 122         if (!region_obj2) {
 123                 return_ACPI_STATUS(AE_NOT_EXIST);
 124         }
 125
 126         /* Ensure that there is a handler associated with this region */
 127
 128         handler_desc = region_obj->region.handler;
 129         if (!handler_desc) {
 130                 ACPI_ERROR((AE_INFO,
 131                             "No handler for Region [%4.4s] (%p) [%s]",
 132                             acpi_ut_get_node_name(region_obj->region.node),
 133                             region_obj,
 134                             acpi_ut_get_region_name(region_obj->region.
 135                                                     space_id)));
 136
 137                 return_ACPI_STATUS(AE_NOT_EXIST);
 138         }
 139
 140         context = handler_desc->address_space.context;
 141         context_mutex = handler_desc->address_space.context_mutex;
 142         context_locked = FALSE;
 143
 144         /*
 145          * It may be the case that the region has never been initialized.
 146          * Some types of regions require special init code
 147          */
 148         if (!(region_obj->region.flags & AOPOBJ_SETUP_COMPLETE)) {
 149
 150                 /* This region has not been initialized yet, do it */
 151
 152                 region_setup = handler_desc->address_space.setup;
 153                 if (!region_setup) {
 154
 155                         /* No initialization routine, exit with error */
 156
 157                         ACPI_ERROR((AE_INFO,
 158                                     "No init routine for region(%p) [%s]",
 159                                     region_obj,
 160                                     acpi_ut_get_region_name(region_obj->region.
 161                                                             space_id)));
 162                         return_ACPI_STATUS(AE_NOT_EXIST);
 163                 }
 164
 165                 if (region_obj->region.space_id == ACPI_ADR_SPACE_PLATFORM_COMM) {
 166                         struct acpi_pcc_info *ctx =
 167                             handler_desc->address_space.context;
 168
 169                         ctx->internal_buffer =
 170                             field_obj->field.internal_pcc_buffer;
 171                         ctx->length = (u16)region_obj->region.length;
 172                         ctx->subspace_id = (u8)region_obj->region.address;
 173                 }
 174
 175                 if (region_obj->region.space_id ==
 176                     ACPI_ADR_SPACE_FIXED_HARDWARE) {
 177                         struct acpi_ffh_info *ctx =
 178                             handler_desc->address_space.context;
 179
 180                         ctx->length = region_obj->region.length;
 181                         ctx->offset = region_obj->region.address;
 182                 }
 183
 184                 /*
 185                  * We must exit the interpreter because the region setup will
 186                  * potentially execute control methods (for example, the _REG method
 187                  * for this region)
 188                  */
 189                 acpi_ex_exit_interpreter();
 190
 191                 status = region_setup(region_obj, ACPI_REGION_ACTIVATE,
 192                                       context, &region_context);
 193
 194                 /* Re-enter the interpreter */
 195
 196                 acpi_ex_enter_interpreter();
 197
 198                 /* Check for failure of the Region Setup */
 199
 200                 if (ACPI_FAILURE(status)) {
 201                         ACPI_EXCEPTION((AE_INFO, status,
 202                                         "During region initialization: [%s]",
 203                                         acpi_ut_get_region_name(region_obj->
 204                                                                 region.
 205                                                                 space_id)));
 206                         return_ACPI_STATUS(status);
 207                 }
 208
 209                 /* Region initialization may have been completed by region_setup */
 210
 211                 if (!(region_obj->region.flags & AOPOBJ_SETUP_COMPLETE)) {
 212                         region_obj->region.flags |= AOPOBJ_SETUP_COMPLETE;
 213
 214                         /*
 215                          * Save the returned context for use in all accesses to
 216                          * the handler for this particular region
 217                          */
 218                         if (!(region_obj2->extra.region_context)) {
 219                                 region_obj2->extra.region_context =
 220                                     region_context;
 221                         }
 222                 }
 223         }
 224
 225         /* We have everything we need, we can invoke the address space handler */
 226
 227         handler = handler_desc->address_space.handler;
 228         address = (region_obj->region.address + region_offset);
 229
 230         ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
 231                           "Handler %p (@%p) Address %8.8X%8.8X [%s]\n",
 232                           &region_obj->region.handler->address_space, handler,
 233                           ACPI_FORMAT_UINT64(address),
 234                           acpi_ut_get_region_name(region_obj->region.
 235                                                   space_id)));
 236
 237         if (!(handler_desc->address_space.handler_flags &
 238               ACPI_ADDR_HANDLER_DEFAULT_INSTALLED)) {
 239                 /*
 240                  * For handlers other than the default (supplied) handlers, we must
 241                  * exit the interpreter because the handler *might* block -- we don't
 242                  * know what it will do, so we can't hold the lock on the interpreter.
 243                  */
 244                 acpi_ex_exit_interpreter();
 245         }
 246
 247         /*
 248          * Special handling for generic_serial_bus and general_purpose_io:
 249          * There are three extra parameters that must be passed to the
 250          * handler via the context:
 251          *   1) Connection buffer, a resource template from Connection() op
 252          *   2) Length of the above buffer
 253          *   3) Actual access length from the access_as() op
 254          *
 255          * Since we pass these extra parameters via the context, which is
 256          * shared between threads, we must lock the context to avoid these
 257          * parameters being changed from another thread before the handler
 258          * has completed running.
 259          *
 260          * In addition, for general_purpose_io, the Address and bit_width fields
 261          * are defined as follows:
 262          *   1) Address is the pin number index of the field (bit offset from
 263          *      the previous Connection)
 264          *   2) bit_width is the actual bit length of the field (number of pins)
 265          */
 266         if ((region_obj->region.space_id == ACPI_ADR_SPACE_GSBUS ||
 267              region_obj->region.space_id == ACPI_ADR_SPACE_GPIO) &&
 268             context && field_obj) {
 269
 270                 status =
 271                     acpi_os_acquire_mutex(context_mutex, ACPI_WAIT_FOREVER);
 272                 if (ACPI_FAILURE(status)) {
 273                         goto re_enter_interpreter;
 274                 }
 275
 276                 context_locked = TRUE;
 277
 278                 /* Get the Connection (resource_template) buffer */
 279
 280                 context->connection = field_obj->field.resource_buffer;
 281                 context->length = field_obj->field.resource_length;
 282                 context->access_length = field_obj->field.access_length;
 283
 284                 if (region_obj->region.space_id == ACPI_ADR_SPACE_GPIO) {
 285                         address = field_obj->field.pin_number_index;
 286                         bit_width = field_obj->field.bit_length;
 287                 }
 288         }
 289
 290         /* Call the handler */
 291
 292         status = handler(function, address, bit_width, value, context,
 293                          region_obj2->extra.region_context);
 294
 295         if (context_locked) {
 296                 acpi_os_release_mutex(context_mutex);
 297         }
 298
 299         if (ACPI_FAILURE(status)) {
 300                 ACPI_EXCEPTION((AE_INFO, status, "Returned by Handler for [%s]",
 301                                 acpi_ut_get_region_name(region_obj->region.
 302                                                         space_id)));
 303
 304                 /*
 305                  * Special case for an EC timeout. These are seen so frequently
 306                  * that an additional error message is helpful
 307                  */
 308                 if ((region_obj->region.space_id == ACPI_ADR_SPACE_EC) &&
 309                     (status == AE_TIME)) {
 310                         ACPI_ERROR((AE_INFO,
 311                                     "Timeout from EC hardware or EC device driver"));
 312                 }
 313         }
 314
 315 re_enter_interpreter:
 316         if (!(handler_desc->address_space.handler_flags &
 317               ACPI_ADDR_HANDLER_DEFAULT_INSTALLED)) {
 318                 /*
 319                  * We just returned from a non-default handler, we must re-enter the
 320                  * interpreter
 321                  */
 322                 acpi_ex_enter_interpreter();
 323         }
 324
 325         return_ACPI_STATUS(status);
 326 }
 327
 328 /*******************************************************************************
 329  *
 330  * FUNCTION:    acpi_ev_detach_region
 331  *
 332  * PARAMETERS:  region_obj          - Region Object
 333  *              acpi_ns_is_locked   - Namespace Region Already Locked?
 334  *
 335  * RETURN:      None
 336  *
 337  * DESCRIPTION: Break the association between the handler and the region
 338  *              this is a two way association.
 339  *
 340  ******************************************************************************/
 341
 342 void
 343 acpi_ev_detach_region(union acpi_operand_object *region_obj,
 344                       u8 acpi_ns_is_locked)
 345 {
 346         union acpi_operand_object *handler_obj;
 347         union acpi_operand_object *obj_desc;
 348         union acpi_operand_object *start_desc;
 349         union acpi_operand_object **last_obj_ptr;
 350         acpi_adr_space_setup region_setup;
 351         void **region_context;
 352         union acpi_operand_object *region_obj2;
 353         acpi_status status;
 354
 355         ACPI_FUNCTION_TRACE(ev_detach_region);
 356
 357         region_obj2 = acpi_ns_get_secondary_object(region_obj);
 358         if (!region_obj2) {
 359                 return_VOID;
 360         }
 361         region_context = &region_obj2->extra.region_context;
 362
 363         /* Get the address handler from the region object */
 364
 365         handler_obj = region_obj->region.handler;
 366         if (!handler_obj) {
 367
 368                 /* This region has no handler, all done */
 369
 370                 return_VOID;
 371         }
 372
 373         /* Find this region in the handler's list */
 374
 375         obj_desc = handler_obj->address_space.region_list;
 376         start_desc = obj_desc;
 377         last_obj_ptr = &handler_obj->address_space.region_list;
 378
 379         while (obj_desc) {
 380
 381                 /* Is this the correct Region? */
 382
 383                 if (obj_desc == region_obj) {
 384                         ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
 385                                           "Removing Region %p from address handler %p\n",
 386                                           region_obj, handler_obj));
 387
 388                         /* This is it, remove it from the handler's list */
 389
 390                         *last_obj_ptr = obj_desc->region.next;
 391                         obj_desc->region.next = NULL;   /* Must clear field */
 392
 393                         if (acpi_ns_is_locked) {
 394                                 status =
 395                                     acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 396                                 if (ACPI_FAILURE(status)) {
 397                                         return_VOID;
 398                                 }
 399                         }
 400
 401                         /* Now stop region accesses by executing the _REG method */
 402
 403                         status =
 404                             acpi_ev_execute_reg_method(region_obj,
 405                                                        ACPI_REG_DISCONNECT);
 406                         if (ACPI_FAILURE(status)) {
 407                                 ACPI_EXCEPTION((AE_INFO, status,
 408                                                 "from region _REG, [%s]",
 409                                                 acpi_ut_get_region_name
 410                                                 (region_obj->region.space_id)));
 411                         }
 412
 413                         if (acpi_ns_is_locked) {
 414                                 status =
 415                                     acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 416                                 if (ACPI_FAILURE(status)) {
 417                                         return_VOID;
 418                                 }
 419                         }
 420
 421                         /*
 422                          * If the region has been activated, call the setup handler with
 423                          * the deactivate notification
 424                          */
 425                         if (region_obj->region.flags & AOPOBJ_SETUP_COMPLETE) {
 426                                 region_setup = handler_obj->address_space.setup;
 427                                 status =
 428                                     region_setup(region_obj,
 429                                                  ACPI_REGION_DEACTIVATE,
 430                                                  handler_obj->address_space.
 431                                                  context, region_context);
 432
 433                                 /*
 434                                  * region_context should have been released by the deactivate
 435                                  * operation. We don't need access to it anymore here.
 436                                  */
 437                                 if (region_context) {
 438                                         *region_context = NULL;
 439                                 }
 440
 441                                 /* Init routine may fail, Just ignore errors */
 442
 443                                 if (ACPI_FAILURE(status)) {
 444                                         ACPI_EXCEPTION((AE_INFO, status,
 445                                                         "from region handler - deactivate, [%s]",
 446                                                         acpi_ut_get_region_name
 447                                                         (region_obj->region.
 448                                                          space_id)));
 449                                 }
 450
 451                                 region_obj->region.flags &=
 452                                     ~(AOPOBJ_SETUP_COMPLETE);
 453                         }
 454
 455                         /*
 456                          * Remove handler reference in the region
 457                          *
 458                          * NOTE: this doesn't mean that the region goes away, the region
 459                          * is just inaccessible as indicated to the _REG method
 460                          *
 461                          * If the region is on the handler's list, this must be the
 462                          * region's handler
 463                          */
 464                         region_obj->region.handler = NULL;
 465                         acpi_ut_remove_reference(handler_obj);
 466
 467                         return_VOID;
 468                 }
 469
 470                 /* Walk the linked list of handlers */
 471
 472                 last_obj_ptr = &obj_desc->region.next;
 473                 obj_desc = obj_desc->region.next;
 474
 475                 /* Prevent infinite loop if list is corrupted */
 476
 477                 if (obj_desc == start_desc) {
 478                         ACPI_ERROR((AE_INFO,
 479                                     "Circular handler list in region object %p",
 480                                     region_obj));
 481                         return_VOID;
 482                 }
 483         }
 484
 485         /* If we get here, the region was not in the handler's region list */
 486
 487         ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
 488                           "Cannot remove region %p from address handler %p\n",
 489                           region_obj, handler_obj));
 490
 491         return_VOID;
 492 }
 493
 494 /*******************************************************************************
 495  *
 496  * FUNCTION:    acpi_ev_attach_region
 497  *
 498  * PARAMETERS:  handler_obj         - Handler Object
 499  *              region_obj          - Region Object
 500  *              acpi_ns_is_locked   - Namespace Region Already Locked?
 501  *
 502  * RETURN:      None
 503  *
 504  * DESCRIPTION: Create the association between the handler and the region
 505  *              this is a two way association.
 506  *
 507  ******************************************************************************/
 508
 509 acpi_status
 510 acpi_ev_attach_region(union acpi_operand_object *handler_obj,
 511                       union acpi_operand_object *region_obj,
 512                       u8 acpi_ns_is_locked)
 513 {
 514
 515         ACPI_FUNCTION_TRACE(ev_attach_region);
 516
 517         /* Install the region's handler */
 518
 519         if (region_obj->region.handler) {
 520                 return_ACPI_STATUS(AE_ALREADY_EXISTS);
 521         }
 522
 523         ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
 524                           "Adding Region [%4.4s] %p to address handler %p [%s]\n",
 525                           acpi_ut_get_node_name(region_obj->region.node),
 526                           region_obj, handler_obj,
 527                           acpi_ut_get_region_name(region_obj->region.
 528                                                   space_id)));
 529
 530         /* Link this region to the front of the handler's list */
 531
 532         region_obj->region.next = handler_obj->address_space.region_list;
 533         handler_obj->address_space.region_list = region_obj;
 534         region_obj->region.handler = handler_obj;
 535         acpi_ut_add_reference(handler_obj);
 536
 537         return_ACPI_STATUS(AE_OK);
 538 }
 539
 540 /*******************************************************************************
 541  *
 542  * FUNCTION:    acpi_ev_execute_reg_method
 543  *
 544  * PARAMETERS:  region_obj          - Region object
 545  *              function            - Passed to _REG: On (1) or Off (0)
 546  *
 547  * RETURN:      Status
 548  *
 549  * DESCRIPTION: Execute _REG method for a region
 550  *
 551  ******************************************************************************/
 552
 553 acpi_status
 554 acpi_ev_execute_reg_method(union acpi_operand_object *region_obj, u32 function)
 555 {
 556         struct acpi_evaluate_info *info;
 557         union acpi_operand_object *args[3];
 558         union acpi_operand_object *region_obj2;
 559         const acpi_name *reg_name_ptr =
 560             ACPI_CAST_PTR(acpi_name, METHOD_NAME__REG);
 561         struct acpi_namespace_node *method_node;
 562         struct acpi_namespace_node *node;
 563         acpi_status status;
 564
 565         ACPI_FUNCTION_TRACE(ev_execute_reg_method);
 566
 567         if (!acpi_gbl_namespace_initialized ||
 568             region_obj->region.handler == NULL) {
 569                 return_ACPI_STATUS(AE_OK);
 570         }
 571
 572         region_obj2 = acpi_ns_get_secondary_object(region_obj);
 573         if (!region_obj2) {
 574                 return_ACPI_STATUS(AE_NOT_EXIST);
 575         }
 576
 577         /*
 578          * Find any "_REG" method associated with this region definition.
 579          * The method should always be updated as this function may be
 580          * invoked after a namespace change.
 581          */
 582         node = region_obj->region.node->parent;
 583         status =
 584             acpi_ns_search_one_scope(*reg_name_ptr, node, ACPI_TYPE_METHOD,
 585                                      &method_node);
 586         if (ACPI_SUCCESS(status)) {
 587                 /*
 588                  * The _REG method is optional and there can be only one per
 589                  * region definition. This will be executed when the handler is
 590                  * attached or removed.
 591                  */
 592                 region_obj2->extra.method_REG = method_node;
 593         }
 594         if (region_obj2->extra.method_REG == NULL) {
 595                 return_ACPI_STATUS(AE_OK);
 596         }
 597
 598         /* _REG(DISCONNECT) should be paired with _REG(CONNECT) */
 599
 600         if ((function == ACPI_REG_CONNECT &&
 601              region_obj->common.flags & AOPOBJ_REG_CONNECTED) ||
 602             (function == ACPI_REG_DISCONNECT &&
 603              !(region_obj->common.flags & AOPOBJ_REG_CONNECTED))) {
 604                 return_ACPI_STATUS(AE_OK);
 605         }
 606
 607         /* Allocate and initialize the evaluation information block */
 608
 609         info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
 610         if (!info) {
 611                 return_ACPI_STATUS(AE_NO_MEMORY);
 612         }
 613
 614         info->prefix_node = region_obj2->extra.method_REG;
 615         info->relative_pathname = NULL;
 616         info->parameters = args;
 617         info->flags = ACPI_IGNORE_RETURN_VALUE;
 618
 619         /*
 620          * The _REG method has two arguments:
 621          *
 622          * arg0 - Integer:
 623          *  Operation region space ID Same value as region_obj->Region.space_id
 624          *
 625          * arg1 - Integer:
 626          *  connection status 1 for connecting the handler, 0 for disconnecting
 627          *  the handler (Passed as a parameter)
 628          */
 629         args[0] =
 630             acpi_ut_create_integer_object((u64)region_obj->region.space_id);
 631         if (!args[0]) {
 632                 status = AE_NO_MEMORY;
 633                 goto cleanup1;
 634         }
 635
 636         args[1] = acpi_ut_create_integer_object((u64)function);
 637         if (!args[1]) {
 638                 status = AE_NO_MEMORY;
 639                 goto cleanup2;
 640         }
 641
 642         args[2] = NULL;         /* Terminate list */
 643
 644         /* Execute the method, no return value */
 645
 646         ACPI_DEBUG_EXEC(acpi_ut_display_init_pathname
 647                         (ACPI_TYPE_METHOD, info->prefix_node, NULL));
 648
 649         status = acpi_ns_evaluate(info);
 650         acpi_ut_remove_reference(args[1]);
 651
 652         if (ACPI_FAILURE(status)) {
 653                 goto cleanup2;
 654         }
 655
 656         if (function == ACPI_REG_CONNECT) {
 657                 region_obj->common.flags |= AOPOBJ_REG_CONNECTED;
 658         } else {
 659                 region_obj->common.flags &= ~AOPOBJ_REG_CONNECTED;
 660         }
 661
 662 cleanup2:
 663         acpi_ut_remove_reference(args[0]);
 664
 665 cleanup1:
 666         ACPI_FREE(info);
 667         return_ACPI_STATUS(status);
 668 }
 669
 670 /*******************************************************************************
 671  *
 672  * FUNCTION:    acpi_ev_execute_reg_methods
 673  *
 674  * PARAMETERS:  node            - Namespace node for the device
 675  *              space_id        - The address space ID
 676  *              function        - Passed to _REG: On (1) or Off (0)
 677  *
 678  * RETURN:      None
 679  *
 680  * DESCRIPTION: Run all _REG methods for the input Space ID;
 681  *              Note: assumes namespace is locked, or system init time.
 682  *
 683  ******************************************************************************/
 684
 685 void
 686 acpi_ev_execute_reg_methods(struct acpi_namespace_node *node,
 687                             acpi_adr_space_type space_id, u32 function)
 688 {
 689         struct acpi_reg_walk_info info;
 690
 691         ACPI_FUNCTION_TRACE(ev_execute_reg_methods);
 692
 693         /*
 694          * These address spaces do not need a call to _REG, since the ACPI
 695          * specification defines them as: "must always be accessible". Since
 696          * they never change state (never become unavailable), no need to ever
 697          * call _REG on them. Also, a data_table is not a "real" address space,
 698          * so do not call _REG. September 2018.
 699          */
 700         if ((space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY) ||
 701             (space_id == ACPI_ADR_SPACE_SYSTEM_IO) ||
 702             (space_id == ACPI_ADR_SPACE_DATA_TABLE)) {
 703                 return_VOID;
 704         }
 705
 706         info.space_id = space_id;
 707         info.function = function;
 708         info.reg_run_count = 0;
 709
 710         ACPI_DEBUG_PRINT_RAW((ACPI_DB_NAMES,
 711                               "    Running _REG methods for SpaceId %s\n",
 712                               acpi_ut_get_region_name(info.space_id)));
 713
 714         /*
 715          * Run all _REG methods for all Operation Regions for this space ID. This
 716          * is a separate walk in order to handle any interdependencies between
 717          * regions and _REG methods. (i.e. handlers must be installed for all
 718          * regions of this Space ID before we can run any _REG methods)
 719          */
 720         (void)acpi_ns_walk_namespace(ACPI_TYPE_ANY, node, ACPI_UINT32_MAX,
 721                                      ACPI_NS_WALK_UNLOCK, acpi_ev_reg_run, NULL,
 722                                      &info, NULL);
 723
 724         /*
 725          * Special case for EC and GPIO: handle "orphan" _REG methods with
 726          * no region.
 727          */
 728         if (space_id == ACPI_ADR_SPACE_EC || space_id == ACPI_ADR_SPACE_GPIO) {
 729                 acpi_ev_execute_orphan_reg_method(node, space_id);
 730         }
 731
 732         ACPI_DEBUG_PRINT_RAW((ACPI_DB_NAMES,
 733                               "    Executed %u _REG methods for SpaceId %s\n",
 734                               info.reg_run_count,
 735                               acpi_ut_get_region_name(info.space_id)));
 736
 737         return_VOID;
 738 }
 739
 740 /*******************************************************************************
 741  *
 742  * FUNCTION:    acpi_ev_reg_run
 743  *
 744  * PARAMETERS:  walk_namespace callback
 745  *
 746  * DESCRIPTION: Run _REG method for region objects of the requested spaceID
 747  *
 748  ******************************************************************************/
 749
 750 static acpi_status
 751 acpi_ev_reg_run(acpi_handle obj_handle,
 752                 u32 level, void *context, void **return_value)
 753 {
 754         union acpi_operand_object *obj_desc;
 755         struct acpi_namespace_node *node;
 756         acpi_status status;
 757         struct acpi_reg_walk_info *info;
 758
 759         info = ACPI_CAST_PTR(struct acpi_reg_walk_info, context);
 760
 761         /* Convert and validate the device handle */
 762
 763         node = acpi_ns_validate_handle(obj_handle);
 764         if (!node) {
 765                 return (AE_BAD_PARAMETER);
 766         }
 767
 768         /*
 769          * We only care about regions and objects that are allowed to have
 770          * address space handlers
 771          */
 772         if ((node->type != ACPI_TYPE_REGION) && (node != acpi_gbl_root_node)) {
 773                 return (AE_OK);
 774         }
 775
 776         /* Check for an existing internal object */
 777
 778         obj_desc = acpi_ns_get_attached_object(node);
 779         if (!obj_desc) {
 780
 781                 /* No object, just exit */
 782
 783                 return (AE_OK);
 784         }
 785
 786         /* Object is a Region */
 787
 788         if (obj_desc->region.space_id != info->space_id) {
 789
 790                 /* This region is for a different address space, just ignore it */
 791
 792                 return (AE_OK);
 793         }
 794
 795         info->reg_run_count++;
 796         status = acpi_ev_execute_reg_method(obj_desc, info->function);
 797         return (status);
 798 }
 799
 800 /*******************************************************************************
 801  *
 802  * FUNCTION:    acpi_ev_execute_orphan_reg_method
 803  *
 804  * PARAMETERS:  device_node         - Namespace node for an ACPI device
 805  *              space_id            - The address space ID
 806  *
 807  * RETURN:      None
 808  *
 809  * DESCRIPTION: Execute an "orphan" _REG method that appears under an ACPI
 810  *              device. This is a _REG method that has no corresponding region
 811  *              within the device's scope. ACPI tables depending on these
 812  *              "orphan" _REG methods have been seen for both EC and GPIO
 813  *              Operation Regions. Presumably the Windows ACPI implementation
 814  *              always calls the _REG method independent of the presence of
 815  *              an actual Operation Region with the correct address space ID.
 816  *
 817  *  MUTEX:      Assumes the namespace is locked
 818  *
 819  ******************************************************************************/
 820
 821 static void
 822 acpi_ev_execute_orphan_reg_method(struct acpi_namespace_node *device_node,
 823                                   acpi_adr_space_type space_id)
 824 {
 825         acpi_handle reg_method;
 826         struct acpi_namespace_node *next_node;
 827         acpi_status status;
 828         struct acpi_object_list args;
 829         union acpi_object objects[2];
 830
 831         ACPI_FUNCTION_TRACE(ev_execute_orphan_reg_method);
 832
 833         if (!device_node) {
 834                 return_VOID;
 835         }
 836
 837         /* Namespace is currently locked, must release */
 838
 839         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 840
 841         /* Get a handle to a _REG method immediately under the EC device */
 842
 843         status = acpi_get_handle(device_node, METHOD_NAME__REG, &reg_method);
 844         if (ACPI_FAILURE(status)) {
 845                 goto exit;      /* There is no _REG method present */
 846         }
 847
 848         /*
 849          * Execute the _REG method only if there is no Operation Region in
 850          * this scope with the Embedded Controller space ID. Otherwise, it
 851          * will already have been executed. Note, this allows for Regions
 852          * with other space IDs to be present; but the code below will then
 853          * execute the _REG method with the embedded_control space_ID argument.
 854          */
 855         next_node = acpi_ns_get_next_node(device_node, NULL);
 856         while (next_node) {
 857                 if ((next_node->type == ACPI_TYPE_REGION) &&
 858                     (next_node->object) &&
 859                     (next_node->object->region.space_id == space_id)) {
 860                         goto exit;      /* Do not execute the _REG */
 861                 }
 862
 863                 next_node = acpi_ns_get_next_node(device_node, next_node);
 864         }
 865
 866         /* Evaluate the _REG(space_id,Connect) method */
 867
 868         args.count = 2;
 869         args.pointer = objects;
 870         objects[0].type = ACPI_TYPE_INTEGER;
 871         objects[0].integer.value = space_id;
 872         objects[1].type = ACPI_TYPE_INTEGER;
 873         objects[1].integer.value = ACPI_REG_CONNECT;
 874
 875         (void)acpi_evaluate_object(reg_method, NULL, &args, NULL);
 876
 877 exit:
 878         /* We ignore all errors from above, don't care */
 879
 880         (void)acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 881         return_VOID;
 882 }