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 - 2020, 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_orphan_ec_reg_method(struct acpi_namespace_node *ec_device_node);
  25
  26 static acpi_status
  27 acpi_ev_reg_run(acpi_handle obj_handle,
  28                 u32 level, void *context, void **return_value);
  29
  30 /*******************************************************************************
  31  *
  32  * FUNCTION:    acpi_ev_initialize_op_regions
  33  *
  34  * PARAMETERS:  None
  35  *
  36  * RETURN:      Status
  37  *
  38  * DESCRIPTION: Execute _REG methods for all Operation Regions that have
  39  *              an installed default region handler.
  40  *
  41  ******************************************************************************/
  42
  43 acpi_status acpi_ev_initialize_op_regions(void)
  44 {
  45         acpi_status status;
  46         u32 i;
  47
  48         ACPI_FUNCTION_TRACE(ev_initialize_op_regions);
  49
  50         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
  51         if (ACPI_FAILURE(status)) {
  52                 return_ACPI_STATUS(status);
  53         }
  54
  55         /* Run the _REG methods for op_regions in each default address space */
  56
  57         for (i = 0; i < ACPI_NUM_DEFAULT_SPACES; i++) {
  58                 /*
  59                  * Make sure the installed handler is the DEFAULT handler. If not the
  60                  * default, the _REG methods will have already been run (when the
  61                  * handler was installed)
  62                  */
  63                 if (acpi_ev_has_default_handler(acpi_gbl_root_node,
  64                                                 acpi_gbl_default_address_spaces
  65                                                 [i])) {
  66                         acpi_ev_execute_reg_methods(acpi_gbl_root_node,
  67                                                     acpi_gbl_default_address_spaces
  68                                                     [i], ACPI_REG_CONNECT);
  69                 }
  70         }
  71
  72         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
  73         return_ACPI_STATUS(status);
  74 }
  75
  76 /*******************************************************************************
  77  *
  78  * FUNCTION:    acpi_ev_address_space_dispatch
  79  *
  80  * PARAMETERS:  region_obj          - Internal region object
  81  *              field_obj           - Corresponding field. Can be NULL.
  82  *              function            - Read or Write operation
  83  *              region_offset       - Where in the region to read or write
  84  *              bit_width           - Field width in bits (8, 16, 32, or 64)
  85  *              value               - Pointer to in or out value, must be
  86  *                                    a full 64-bit integer
  87  *
  88  * RETURN:      Status
  89  *
  90  * DESCRIPTION: Dispatch an address space or operation region access to
  91  *              a previously installed handler.
  92  *
  93  * NOTE: During early initialization, we always install the default region
  94  * handlers for Memory, I/O and PCI_Config. This ensures that these operation
  95  * region address spaces are always available as per the ACPI specification.
  96  * This is especially needed in order to support the execution of
  97  * module-level AML code during loading of the ACPI tables.
  98  *
  99  ******************************************************************************/
 100
 101 acpi_status
 102 acpi_ev_address_space_dispatch(union acpi_operand_object *region_obj,
 103                                union acpi_operand_object *field_obj,
 104                                u32 function,
 105                                u32 region_offset, u32 bit_width, u64 *value)
 106 {
 107         acpi_status status;
 108         acpi_adr_space_handler handler;
 109         acpi_adr_space_setup region_setup;
 110         union acpi_operand_object *handler_desc;
 111         union acpi_operand_object *region_obj2;
 112         void *region_context = NULL;
 113         struct acpi_connection_info *context;
 114         acpi_mutex context_mutex;
 115         u8 context_locked;
 116         acpi_physical_address address;
 117
 118         ACPI_FUNCTION_TRACE(ev_address_space_dispatch);
 119
 120         region_obj2 = acpi_ns_get_secondary_object(region_obj);
 121         if (!region_obj2) {
 122                 return_ACPI_STATUS(AE_NOT_EXIST);
 123         }
 124
 125         /* Ensure that there is a handler associated with this region */
 126
 127         handler_desc = region_obj->region.handler;
 128         if (!handler_desc) {
 129                 ACPI_ERROR((AE_INFO,
 130                             "No handler for Region [%4.4s] (%p) [%s]",
 131                             acpi_ut_get_node_name(region_obj->region.node),
 132                             region_obj,
 133                             acpi_ut_get_region_name(region_obj->region.
 134                                                     space_id)));
 135
 136                 return_ACPI_STATUS(AE_NOT_EXIST);
 137         }
 138
 139         context = handler_desc->address_space.context;
 140         context_mutex = handler_desc->address_space.context_mutex;
 141         context_locked = FALSE;
 142
 143         /*
 144          * It may be the case that the region has never been initialized.
 145          * Some types of regions require special init code
 146          */
 147         if (!(region_obj->region.flags & AOPOBJ_SETUP_COMPLETE)) {
 148
 149                 /* This region has not been initialized yet, do it */
 150
 151                 region_setup = handler_desc->address_space.setup;
 152                 if (!region_setup) {
 153
 154                         /* No initialization routine, exit with error */
 155
 156                         ACPI_ERROR((AE_INFO,
 157                                     "No init routine for region(%p) [%s]",
 158                                     region_obj,
 159                                     acpi_ut_get_region_name(region_obj->region.
 160                                                             space_id)));
 161                         return_ACPI_STATUS(AE_NOT_EXIST);
 162                 }
 163
 164                 /*
 165                  * We must exit the interpreter because the region setup will
 166                  * potentially execute control methods (for example, the _REG method
 167                  * for this region)
 168                  */
 169                 acpi_ex_exit_interpreter();
 170
 171                 status = region_setup(region_obj, ACPI_REGION_ACTIVATE,
 172                                       context, &region_context);
 173
 174                 /* Re-enter the interpreter */
 175
 176                 acpi_ex_enter_interpreter();
 177
 178                 /* Check for failure of the Region Setup */
 179
 180                 if (ACPI_FAILURE(status)) {
 181                         ACPI_EXCEPTION((AE_INFO, status,
 182                                         "During region initialization: [%s]",
 183                                         acpi_ut_get_region_name(region_obj->
 184                                                                 region.
 185                                                                 space_id)));
 186                         return_ACPI_STATUS(status);
 187                 }
 188
 189                 /* Region initialization may have been completed by region_setup */
 190
 191                 if (!(region_obj->region.flags & AOPOBJ_SETUP_COMPLETE)) {
 192                         region_obj->region.flags |= AOPOBJ_SETUP_COMPLETE;
 193
 194                         /*
 195                          * Save the returned context for use in all accesses to
 196                          * the handler for this particular region
 197                          */
 198                         if (!(region_obj2->extra.region_context)) {
 199                                 region_obj2->extra.region_context =
 200                                     region_context;
 201                         }
 202                 }
 203         }
 204
 205         /* We have everything we need, we can invoke the address space handler */
 206
 207         handler = handler_desc->address_space.handler;
 208         address = (region_obj->region.address + region_offset);
 209
 210         ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
 211                           "Handler %p (@%p) Address %8.8X%8.8X [%s]\n",
 212                           &region_obj->region.handler->address_space, handler,
 213                           ACPI_FORMAT_UINT64(address),
 214                           acpi_ut_get_region_name(region_obj->region.
 215                                                   space_id)));
 216
 217         if (!(handler_desc->address_space.handler_flags &
 218               ACPI_ADDR_HANDLER_DEFAULT_INSTALLED)) {
 219                 /*
 220                  * For handlers other than the default (supplied) handlers, we must
 221                  * exit the interpreter because the handler *might* block -- we don't
 222                  * know what it will do, so we can't hold the lock on the interpreter.
 223                  */
 224                 acpi_ex_exit_interpreter();
 225         }
 226
 227         /*
 228          * Special handling for generic_serial_bus and general_purpose_io:
 229          * There are three extra parameters that must be passed to the
 230          * handler via the context:
 231          *   1) Connection buffer, a resource template from Connection() op
 232          *   2) Length of the above buffer
 233          *   3) Actual access length from the access_as() op
 234          *
 235          * Since we pass these extra parameters via the context, which is
 236          * shared between threads, we must lock the context to avoid these
 237          * parameters being changed from another thread before the handler
 238          * has completed running.
 239          *
 240          * In addition, for general_purpose_io, the Address and bit_width fields
 241          * are defined as follows:
 242          *   1) Address is the pin number index of the field (bit offset from
 243          *      the previous Connection)
 244          *   2) bit_width is the actual bit length of the field (number of pins)
 245          */
 246         if ((region_obj->region.space_id == ACPI_ADR_SPACE_GSBUS) &&
 247             context && field_obj) {
 248
 249                 status =
 250                     acpi_os_acquire_mutex(context_mutex, ACPI_WAIT_FOREVER);
 251                 if (ACPI_FAILURE(status)) {
 252                         goto re_enter_interpreter;
 253                 }
 254
 255                 context_locked = TRUE;
 256
 257                 /* Get the Connection (resource_template) buffer */
 258
 259                 context->connection = field_obj->field.resource_buffer;
 260                 context->length = field_obj->field.resource_length;
 261                 context->access_length = field_obj->field.access_length;
 262         }
 263         if ((region_obj->region.space_id == ACPI_ADR_SPACE_GPIO) &&
 264             context && field_obj) {
 265
 266                 status =
 267                     acpi_os_acquire_mutex(context_mutex, ACPI_WAIT_FOREVER);
 268                 if (ACPI_FAILURE(status)) {
 269                         goto re_enter_interpreter;
 270                 }
 271
 272                 context_locked = TRUE;
 273
 274                 /* Get the Connection (resource_template) buffer */
 275
 276                 context->connection = field_obj->field.resource_buffer;
 277                 context->length = field_obj->field.resource_length;
 278                 context->access_length = field_obj->field.access_length;
 279                 address = field_obj->field.pin_number_index;
 280                 bit_width = field_obj->field.bit_length;
 281         }
 282
 283         /* Call the handler */
 284
 285         status = handler(function, address, bit_width, value, context,
 286                          region_obj2->extra.region_context);
 287
 288         if (context_locked) {
 289                 acpi_os_release_mutex(context_mutex);
 290         }
 291
 292         if (ACPI_FAILURE(status)) {
 293                 ACPI_EXCEPTION((AE_INFO, status, "Returned by Handler for [%s]",
 294                                 acpi_ut_get_region_name(region_obj->region.
 295                                                         space_id)));
 296
 297                 /*
 298                  * Special case for an EC timeout. These are seen so frequently
 299                  * that an additional error message is helpful
 300                  */
 301                 if ((region_obj->region.space_id == ACPI_ADR_SPACE_EC) &&
 302                     (status == AE_TIME)) {
 303                         ACPI_ERROR((AE_INFO,
 304                                     "Timeout from EC hardware or EC device driver"));
 305                 }
 306         }
 307
 308 re_enter_interpreter:
 309         if (!(handler_desc->address_space.handler_flags &
 310               ACPI_ADDR_HANDLER_DEFAULT_INSTALLED)) {
 311                 /*
 312                  * We just returned from a non-default handler, we must re-enter the
 313                  * interpreter
 314                  */
 315                 acpi_ex_enter_interpreter();
 316         }
 317
 318         return_ACPI_STATUS(status);
 319 }
 320
 321 /*******************************************************************************
 322  *
 323  * FUNCTION:    acpi_ev_detach_region
 324  *
 325  * PARAMETERS:  region_obj          - Region Object
 326  *              acpi_ns_is_locked   - Namespace Region Already Locked?
 327  *
 328  * RETURN:      None
 329  *
 330  * DESCRIPTION: Break the association between the handler and the region
 331  *              this is a two way association.
 332  *
 333  ******************************************************************************/
 334
 335 void
 336 acpi_ev_detach_region(union acpi_operand_object *region_obj,
 337                       u8 acpi_ns_is_locked)
 338 {
 339         union acpi_operand_object *handler_obj;
 340         union acpi_operand_object *obj_desc;
 341         union acpi_operand_object *start_desc;
 342         union acpi_operand_object **last_obj_ptr;
 343         acpi_adr_space_setup region_setup;
 344         void **region_context;
 345         union acpi_operand_object *region_obj2;
 346         acpi_status status;
 347
 348         ACPI_FUNCTION_TRACE(ev_detach_region);
 349
 350         region_obj2 = acpi_ns_get_secondary_object(region_obj);
 351         if (!region_obj2) {
 352                 return_VOID;
 353         }
 354         region_context = &region_obj2->extra.region_context;
 355
 356         /* Get the address handler from the region object */
 357
 358         handler_obj = region_obj->region.handler;
 359         if (!handler_obj) {
 360
 361                 /* This region has no handler, all done */
 362
 363                 return_VOID;
 364         }
 365
 366         /* Find this region in the handler's list */
 367
 368         obj_desc = handler_obj->address_space.region_list;
 369         start_desc = obj_desc;
 370         last_obj_ptr = &handler_obj->address_space.region_list;
 371
 372         while (obj_desc) {
 373
 374                 /* Is this the correct Region? */
 375
 376                 if (obj_desc == region_obj) {
 377                         ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
 378                                           "Removing Region %p from address handler %p\n",
 379                                           region_obj, handler_obj));
 380
 381                         /* This is it, remove it from the handler's list */
 382
 383                         *last_obj_ptr = obj_desc->region.next;
 384                         obj_desc->region.next = NULL;   /* Must clear field */
 385
 386                         if (acpi_ns_is_locked) {
 387                                 status =
 388                                     acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 389                                 if (ACPI_FAILURE(status)) {
 390                                         return_VOID;
 391                                 }
 392                         }
 393
 394                         /* Now stop region accesses by executing the _REG method */
 395
 396                         status =
 397                             acpi_ev_execute_reg_method(region_obj,
 398                                                        ACPI_REG_DISCONNECT);
 399                         if (ACPI_FAILURE(status)) {
 400                                 ACPI_EXCEPTION((AE_INFO, status,
 401                                                 "from region _REG, [%s]",
 402                                                 acpi_ut_get_region_name
 403                                                 (region_obj->region.space_id)));
 404                         }
 405
 406                         if (acpi_ns_is_locked) {
 407                                 status =
 408                                     acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 409                                 if (ACPI_FAILURE(status)) {
 410                                         return_VOID;
 411                                 }
 412                         }
 413
 414                         /*
 415                          * If the region has been activated, call the setup handler with
 416                          * the deactivate notification
 417                          */
 418                         if (region_obj->region.flags & AOPOBJ_SETUP_COMPLETE) {
 419                                 region_setup = handler_obj->address_space.setup;
 420                                 status =
 421                                     region_setup(region_obj,
 422                                                  ACPI_REGION_DEACTIVATE,
 423                                                  handler_obj->address_space.
 424                                                  context, region_context);
 425
 426                                 /*
 427                                  * region_context should have been released by the deactivate
 428                                  * operation. We don't need access to it anymore here.
 429                                  */
 430                                 if (region_context) {
 431                                         *region_context = NULL;
 432                                 }
 433
 434                                 /* Init routine may fail, Just ignore errors */
 435
 436                                 if (ACPI_FAILURE(status)) {
 437                                         ACPI_EXCEPTION((AE_INFO, status,
 438                                                         "from region handler - deactivate, [%s]",
 439                                                         acpi_ut_get_region_name
 440                                                         (region_obj->region.
 441                                                          space_id)));
 442                                 }
 443
 444                                 region_obj->region.flags &=
 445                                     ~(AOPOBJ_SETUP_COMPLETE);
 446                         }
 447
 448                         /*
 449                          * Remove handler reference in the region
 450                          *
 451                          * NOTE: this doesn't mean that the region goes away, the region
 452                          * is just inaccessible as indicated to the _REG method
 453                          *
 454                          * If the region is on the handler's list, this must be the
 455                          * region's handler
 456                          */
 457                         region_obj->region.handler = NULL;
 458                         acpi_ut_remove_reference(handler_obj);
 459
 460                         return_VOID;
 461                 }
 462
 463                 /* Walk the linked list of handlers */
 464
 465                 last_obj_ptr = &obj_desc->region.next;
 466                 obj_desc = obj_desc->region.next;
 467
 468                 /* Prevent infinite loop if list is corrupted */
 469
 470                 if (obj_desc == start_desc) {
 471                         ACPI_ERROR((AE_INFO,
 472                                     "Circular handler list in region object %p",
 473                                     region_obj));
 474                         return_VOID;
 475                 }
 476         }
 477
 478         /* If we get here, the region was not in the handler's region list */
 479
 480         ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
 481                           "Cannot remove region %p from address handler %p\n",
 482                           region_obj, handler_obj));
 483
 484         return_VOID;
 485 }
 486
 487 /*******************************************************************************
 488  *
 489  * FUNCTION:    acpi_ev_attach_region
 490  *
 491  * PARAMETERS:  handler_obj         - Handler Object
 492  *              region_obj          - Region Object
 493  *              acpi_ns_is_locked   - Namespace Region Already Locked?
 494  *
 495  * RETURN:      None
 496  *
 497  * DESCRIPTION: Create the association between the handler and the region
 498  *              this is a two way association.
 499  *
 500  ******************************************************************************/
 501
 502 acpi_status
 503 acpi_ev_attach_region(union acpi_operand_object *handler_obj,
 504                       union acpi_operand_object *region_obj,
 505                       u8 acpi_ns_is_locked)
 506 {
 507
 508         ACPI_FUNCTION_TRACE(ev_attach_region);
 509
 510         /* Install the region's handler */
 511
 512         if (region_obj->region.handler) {
 513                 return_ACPI_STATUS(AE_ALREADY_EXISTS);
 514         }
 515
 516         ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
 517                           "Adding Region [%4.4s] %p to address handler %p [%s]\n",
 518                           acpi_ut_get_node_name(region_obj->region.node),
 519                           region_obj, handler_obj,
 520                           acpi_ut_get_region_name(region_obj->region.
 521                                                   space_id)));
 522
 523         /* Link this region to the front of the handler's list */
 524
 525         region_obj->region.next = handler_obj->address_space.region_list;
 526         handler_obj->address_space.region_list = region_obj;
 527         region_obj->region.handler = handler_obj;
 528         acpi_ut_add_reference(handler_obj);
 529
 530         return_ACPI_STATUS(AE_OK);
 531 }
 532
 533 /*******************************************************************************
 534  *
 535  * FUNCTION:    acpi_ev_execute_reg_method
 536  *
 537  * PARAMETERS:  region_obj          - Region object
 538  *              function            - Passed to _REG: On (1) or Off (0)
 539  *
 540  * RETURN:      Status
 541  *
 542  * DESCRIPTION: Execute _REG method for a region
 543  *
 544  ******************************************************************************/
 545
 546 acpi_status
 547 acpi_ev_execute_reg_method(union acpi_operand_object *region_obj, u32 function)
 548 {
 549         struct acpi_evaluate_info *info;
 550         union acpi_operand_object *args[3];
 551         union acpi_operand_object *region_obj2;
 552         const acpi_name *reg_name_ptr =
 553             ACPI_CAST_PTR(acpi_name, METHOD_NAME__REG);
 554         struct acpi_namespace_node *method_node;
 555         struct acpi_namespace_node *node;
 556         acpi_status status;
 557
 558         ACPI_FUNCTION_TRACE(ev_execute_reg_method);
 559
 560         if (!acpi_gbl_namespace_initialized ||
 561             region_obj->region.handler == NULL) {
 562                 return_ACPI_STATUS(AE_OK);
 563         }
 564
 565         region_obj2 = acpi_ns_get_secondary_object(region_obj);
 566         if (!region_obj2) {
 567                 return_ACPI_STATUS(AE_NOT_EXIST);
 568         }
 569
 570         /*
 571          * Find any "_REG" method associated with this region definition.
 572          * The method should always be updated as this function may be
 573          * invoked after a namespace change.
 574          */
 575         node = region_obj->region.node->parent;
 576         status =
 577             acpi_ns_search_one_scope(*reg_name_ptr, node, ACPI_TYPE_METHOD,
 578                                      &method_node);
 579         if (ACPI_SUCCESS(status)) {
 580                 /*
 581                  * The _REG method is optional and there can be only one per
 582                  * region definition. This will be executed when the handler is
 583                  * attached or removed.
 584                  */
 585                 region_obj2->extra.method_REG = method_node;
 586         }
 587         if (region_obj2->extra.method_REG == NULL) {
 588                 return_ACPI_STATUS(AE_OK);
 589         }
 590
 591         /* _REG(DISCONNECT) should be paired with _REG(CONNECT) */
 592
 593         if ((function == ACPI_REG_CONNECT &&
 594              region_obj->common.flags & AOPOBJ_REG_CONNECTED) ||
 595             (function == ACPI_REG_DISCONNECT &&
 596              !(region_obj->common.flags & AOPOBJ_REG_CONNECTED))) {
 597                 return_ACPI_STATUS(AE_OK);
 598         }
 599
 600         /* Allocate and initialize the evaluation information block */
 601
 602         info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
 603         if (!info) {
 604                 return_ACPI_STATUS(AE_NO_MEMORY);
 605         }
 606
 607         info->prefix_node = region_obj2->extra.method_REG;
 608         info->relative_pathname = NULL;
 609         info->parameters = args;
 610         info->flags = ACPI_IGNORE_RETURN_VALUE;
 611
 612         /*
 613          * The _REG method has two arguments:
 614          *
 615          * arg0 - Integer:
 616          *  Operation region space ID Same value as region_obj->Region.space_id
 617          *
 618          * arg1 - Integer:
 619          *  connection status 1 for connecting the handler, 0 for disconnecting
 620          *  the handler (Passed as a parameter)
 621          */
 622         args[0] =
 623             acpi_ut_create_integer_object((u64)region_obj->region.space_id);
 624         if (!args[0]) {
 625                 status = AE_NO_MEMORY;
 626                 goto cleanup1;
 627         }
 628
 629         args[1] = acpi_ut_create_integer_object((u64)function);
 630         if (!args[1]) {
 631                 status = AE_NO_MEMORY;
 632                 goto cleanup2;
 633         }
 634
 635         args[2] = NULL;         /* Terminate list */
 636
 637         /* Execute the method, no return value */
 638
 639         ACPI_DEBUG_EXEC(acpi_ut_display_init_pathname
 640                         (ACPI_TYPE_METHOD, info->prefix_node, NULL));
 641
 642         status = acpi_ns_evaluate(info);
 643         acpi_ut_remove_reference(args[1]);
 644
 645         if (ACPI_FAILURE(status)) {
 646                 goto cleanup2;
 647         }
 648
 649         if (function == ACPI_REG_CONNECT) {
 650                 region_obj->common.flags |= AOPOBJ_REG_CONNECTED;
 651         } else {
 652                 region_obj->common.flags &= ~AOPOBJ_REG_CONNECTED;
 653         }
 654
 655 cleanup2:
 656         acpi_ut_remove_reference(args[0]);
 657
 658 cleanup1:
 659         ACPI_FREE(info);
 660         return_ACPI_STATUS(status);
 661 }
 662
 663 /*******************************************************************************
 664  *
 665  * FUNCTION:    acpi_ev_execute_reg_methods
 666  *
 667  * PARAMETERS:  node            - Namespace node for the device
 668  *              space_id        - The address space ID
 669  *              function        - Passed to _REG: On (1) or Off (0)
 670  *
 671  * RETURN:      None
 672  *
 673  * DESCRIPTION: Run all _REG methods for the input Space ID;
 674  *              Note: assumes namespace is locked, or system init time.
 675  *
 676  ******************************************************************************/
 677
 678 void
 679 acpi_ev_execute_reg_methods(struct acpi_namespace_node *node,
 680                             acpi_adr_space_type space_id, u32 function)
 681 {
 682         struct acpi_reg_walk_info info;
 683
 684         ACPI_FUNCTION_TRACE(ev_execute_reg_methods);
 685
 686         /*
 687          * These address spaces do not need a call to _REG, since the ACPI
 688          * specification defines them as: "must always be accessible". Since
 689          * they never change state (never become unavailable), no need to ever
 690          * call _REG on them. Also, a data_table is not a "real" address space,
 691          * so do not call _REG. September 2018.
 692          */
 693         if ((space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY) ||
 694             (space_id == ACPI_ADR_SPACE_SYSTEM_IO) ||
 695             (space_id == ACPI_ADR_SPACE_DATA_TABLE)) {
 696                 return_VOID;
 697         }
 698
 699         info.space_id = space_id;
 700         info.function = function;
 701         info.reg_run_count = 0;
 702
 703         ACPI_DEBUG_PRINT_RAW((ACPI_DB_NAMES,
 704                               "    Running _REG methods for SpaceId %s\n",
 705                               acpi_ut_get_region_name(info.space_id)));
 706
 707         /*
 708          * Run all _REG methods for all Operation Regions for this space ID. This
 709          * is a separate walk in order to handle any interdependencies between
 710          * regions and _REG methods. (i.e. handlers must be installed for all
 711          * regions of this Space ID before we can run any _REG methods)
 712          */
 713         (void)acpi_ns_walk_namespace(ACPI_TYPE_ANY, node, ACPI_UINT32_MAX,
 714                                      ACPI_NS_WALK_UNLOCK, acpi_ev_reg_run, NULL,
 715                                      &info, NULL);
 716
 717         /* Special case for EC: handle "orphan" _REG methods with no region */
 718
 719         if (space_id == ACPI_ADR_SPACE_EC) {
 720                 acpi_ev_orphan_ec_reg_method(node);
 721         }
 722
 723         ACPI_DEBUG_PRINT_RAW((ACPI_DB_NAMES,
 724                               "    Executed %u _REG methods for SpaceId %s\n",
 725                               info.reg_run_count,
 726                               acpi_ut_get_region_name(info.space_id)));
 727
 728         return_VOID;
 729 }
 730
 731 /*******************************************************************************
 732  *
 733  * FUNCTION:    acpi_ev_reg_run
 734  *
 735  * PARAMETERS:  walk_namespace callback
 736  *
 737  * DESCRIPTION: Run _REG method for region objects of the requested spaceID
 738  *
 739  ******************************************************************************/
 740
 741 static acpi_status
 742 acpi_ev_reg_run(acpi_handle obj_handle,
 743                 u32 level, void *context, void **return_value)
 744 {
 745         union acpi_operand_object *obj_desc;
 746         struct acpi_namespace_node *node;
 747         acpi_status status;
 748         struct acpi_reg_walk_info *info;
 749
 750         info = ACPI_CAST_PTR(struct acpi_reg_walk_info, context);
 751
 752         /* Convert and validate the device handle */
 753
 754         node = acpi_ns_validate_handle(obj_handle);
 755         if (!node) {
 756                 return (AE_BAD_PARAMETER);
 757         }
 758
 759         /*
 760          * We only care about regions and objects that are allowed to have
 761          * address space handlers
 762          */
 763         if ((node->type != ACPI_TYPE_REGION) && (node != acpi_gbl_root_node)) {
 764                 return (AE_OK);
 765         }
 766
 767         /* Check for an existing internal object */
 768
 769         obj_desc = acpi_ns_get_attached_object(node);
 770         if (!obj_desc) {
 771
 772                 /* No object, just exit */
 773
 774                 return (AE_OK);
 775         }
 776
 777         /* Object is a Region */
 778
 779         if (obj_desc->region.space_id != info->space_id) {
 780
 781                 /* This region is for a different address space, just ignore it */
 782
 783                 return (AE_OK);
 784         }
 785
 786         info->reg_run_count++;
 787         status = acpi_ev_execute_reg_method(obj_desc, info->function);
 788         return (status);
 789 }
 790
 791 /*******************************************************************************
 792  *
 793  * FUNCTION:    acpi_ev_orphan_ec_reg_method
 794  *
 795  * PARAMETERS:  ec_device_node      - Namespace node for an EC device
 796  *
 797  * RETURN:      None
 798  *
 799  * DESCRIPTION: Execute an "orphan" _REG method that appears under the EC
 800  *              device. This is a _REG method that has no corresponding region
 801  *              within the EC device scope. The orphan _REG method appears to
 802  *              have been enabled by the description of the ECDT in the ACPI
 803  *              specification: "The availability of the region space can be
 804  *              detected by providing a _REG method object underneath the
 805  *              Embedded Controller device."
 806  *
 807  *              To quickly access the EC device, we use the ec_device_node used
 808  *              during EC handler installation. Otherwise, we would need to
 809  *              perform a time consuming namespace walk, executing _HID
 810  *              methods to find the EC device.
 811  *
 812  *  MUTEX:      Assumes the namespace is locked
 813  *
 814  ******************************************************************************/
 815
 816 static void
 817 acpi_ev_orphan_ec_reg_method(struct acpi_namespace_node *ec_device_node)
 818 {
 819         acpi_handle reg_method;
 820         struct acpi_namespace_node *next_node;
 821         acpi_status status;
 822         struct acpi_object_list args;
 823         union acpi_object objects[2];
 824
 825         ACPI_FUNCTION_TRACE(ev_orphan_ec_reg_method);
 826
 827         if (!ec_device_node) {
 828                 return_VOID;
 829         }
 830
 831         /* Namespace is currently locked, must release */
 832
 833         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 834
 835         /* Get a handle to a _REG method immediately under the EC device */
 836
 837         status = acpi_get_handle(ec_device_node, METHOD_NAME__REG, &reg_method);
 838         if (ACPI_FAILURE(status)) {
 839                 goto exit;      /* There is no _REG method present */
 840         }
 841
 842         /*
 843          * Execute the _REG method only if there is no Operation Region in
 844          * this scope with the Embedded Controller space ID. Otherwise, it
 845          * will already have been executed. Note, this allows for Regions
 846          * with other space IDs to be present; but the code below will then
 847          * execute the _REG method with the embedded_control space_ID argument.
 848          */
 849         next_node = acpi_ns_get_next_node(ec_device_node, NULL);
 850         while (next_node) {
 851                 if ((next_node->type == ACPI_TYPE_REGION) &&
 852                     (next_node->object) &&
 853                     (next_node->object->region.space_id == ACPI_ADR_SPACE_EC)) {
 854                         goto exit;      /* Do not execute the _REG */
 855                 }
 856
 857                 next_node = acpi_ns_get_next_node(ec_device_node, next_node);
 858         }
 859
 860         /* Evaluate the _REG(embedded_control,Connect) method */
 861
 862         args.count = 2;
 863         args.pointer = objects;
 864         objects[0].type = ACPI_TYPE_INTEGER;
 865         objects[0].integer.value = ACPI_ADR_SPACE_EC;
 866         objects[1].type = ACPI_TYPE_INTEGER;
 867         objects[1].integer.value = ACPI_REG_CONNECT;
 868
 869         (void)acpi_evaluate_object(reg_method, NULL, &args, NULL);
 870
 871 exit:
 872         /* We ignore all errors from above, don't care */
 873
 874         (void)acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 875         return_VOID;
 876 }