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_UINT32_MAX,
  69                                                     acpi_gbl_default_address_spaces
  70                                                     [i], ACPI_REG_CONNECT);
  71                 }
  72         }
  73
  74         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
  75         return_ACPI_STATUS(status);
  76 }
  77
  78 /*******************************************************************************
  79  *
  80  * FUNCTION:    acpi_ev_address_space_dispatch
  81  *
  82  * PARAMETERS:  region_obj          - Internal region object
  83  *              field_obj           - Corresponding field. Can be NULL.
  84  *              function            - Read or Write operation
  85  *              region_offset       - Where in the region to read or write
  86  *              bit_width           - Field width in bits (8, 16, 32, or 64)
  87  *              value               - Pointer to in or out value, must be
  88  *                                    a full 64-bit integer
  89  *
  90  * RETURN:      Status
  91  *
  92  * DESCRIPTION: Dispatch an address space or operation region access to
  93  *              a previously installed handler.
  94  *
  95  * NOTE: During early initialization, we always install the default region
  96  * handlers for Memory, I/O and PCI_Config. This ensures that these operation
  97  * region address spaces are always available as per the ACPI specification.
  98  * This is especially needed in order to support the execution of
  99  * module-level AML code during loading of the ACPI tables.
 100  *
 101  ******************************************************************************/
 102
 103 acpi_status
 104 acpi_ev_address_space_dispatch(union acpi_operand_object *region_obj,
 105                                union acpi_operand_object *field_obj,
 106                                u32 function,
 107                                u32 region_offset, u32 bit_width, u64 *value)
 108 {
 109         acpi_status status;
 110         acpi_adr_space_handler handler;
 111         acpi_adr_space_setup region_setup;
 112         union acpi_operand_object *handler_desc;
 113         union acpi_operand_object *region_obj2;
 114         void *region_context = NULL;
 115         struct acpi_connection_info *context;
 116         acpi_mutex context_mutex;
 117         u8 context_locked;
 118         acpi_physical_address address;
 119
 120         ACPI_FUNCTION_TRACE(ev_address_space_dispatch);
 121
 122         region_obj2 = acpi_ns_get_secondary_object(region_obj);
 123         if (!region_obj2) {
 124                 return_ACPI_STATUS(AE_NOT_EXIST);
 125         }
 126
 127         /* Ensure that there is a handler associated with this region */
 128
 129         handler_desc = region_obj->region.handler;
 130         if (!handler_desc) {
 131                 ACPI_ERROR((AE_INFO,
 132                             "No handler for Region [%4.4s] (%p) [%s]",
 133                             acpi_ut_get_node_name(region_obj->region.node),
 134                             region_obj,
 135                             acpi_ut_get_region_name(region_obj->region.
 136                                                     space_id)));
 137
 138                 return_ACPI_STATUS(AE_NOT_EXIST);
 139         }
 140
 141         context = handler_desc->address_space.context;
 142         context_mutex = handler_desc->address_space.context_mutex;
 143         context_locked = FALSE;
 144
 145         /*
 146          * It may be the case that the region has never been initialized.
 147          * Some types of regions require special init code
 148          */
 149         if (!(region_obj->region.flags & AOPOBJ_SETUP_COMPLETE)) {
 150
 151                 /* This region has not been initialized yet, do it */
 152
 153                 region_setup = handler_desc->address_space.setup;
 154                 if (!region_setup) {
 155
 156                         /* No initialization routine, exit with error */
 157
 158                         ACPI_ERROR((AE_INFO,
 159                                     "No init routine for region(%p) [%s]",
 160                                     region_obj,
 161                                     acpi_ut_get_region_name(region_obj->region.
 162                                                             space_id)));
 163                         return_ACPI_STATUS(AE_NOT_EXIST);
 164                 }
 165
 166                 if (region_obj->region.space_id == ACPI_ADR_SPACE_PLATFORM_COMM) {
 167                         struct acpi_pcc_info *ctx =
 168                             handler_desc->address_space.context;
 169
 170                         ctx->internal_buffer =
 171                             field_obj->field.internal_pcc_buffer;
 172                         ctx->length = (u16)region_obj->region.length;
 173                         ctx->subspace_id = (u8)region_obj->region.address;
 174                 }
 175
 176                 if (region_obj->region.space_id ==
 177                     ACPI_ADR_SPACE_FIXED_HARDWARE) {
 178                         struct acpi_ffh_info *ctx =
 179                             handler_desc->address_space.context;
 180
 181                         ctx->length = region_obj->region.length;
 182                         ctx->offset = region_obj->region.address;
 183                 }
 184
 185                 /*
 186                  * We must exit the interpreter because the region setup will
 187                  * potentially execute control methods (for example, the _REG method
 188                  * for this region)
 189                  */
 190                 acpi_ex_exit_interpreter();
 191
 192                 status = region_setup(region_obj, ACPI_REGION_ACTIVATE,
 193                                       context, &region_context);
 194
 195                 /* Re-enter the interpreter */
 196
 197                 acpi_ex_enter_interpreter();
 198
 199                 /* Check for failure of the Region Setup */
 200
 201                 if (ACPI_FAILURE(status)) {
 202                         ACPI_EXCEPTION((AE_INFO, status,
 203                                         "During region initialization: [%s]",
 204                                         acpi_ut_get_region_name(region_obj->
 205                                                                 region.
 206                                                                 space_id)));
 207                         return_ACPI_STATUS(status);
 208                 }
 209
 210                 /* Region initialization may have been completed by region_setup */
 211
 212                 if (!(region_obj->region.flags & AOPOBJ_SETUP_COMPLETE)) {
 213                         region_obj->region.flags |= AOPOBJ_SETUP_COMPLETE;
 214
 215                         /*
 216                          * Save the returned context for use in all accesses to
 217                          * the handler for this particular region
 218                          */
 219                         if (!(region_obj2->extra.region_context)) {
 220                                 region_obj2->extra.region_context =
 221                                     region_context;
 222                         }
 223                 }
 224         }
 225
 226         /* We have everything we need, we can invoke the address space handler */
 227
 228         handler = handler_desc->address_space.handler;
 229         address = (region_obj->region.address + region_offset);
 230
 231         ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
 232                           "Handler %p (@%p) Address %8.8X%8.8X [%s]\n",
 233                           &region_obj->region.handler->address_space, handler,
 234                           ACPI_FORMAT_UINT64(address),
 235                           acpi_ut_get_region_name(region_obj->region.
 236                                                   space_id)));
 237
 238         if (!(handler_desc->address_space.handler_flags &
 239               ACPI_ADDR_HANDLER_DEFAULT_INSTALLED)) {
 240                 /*
 241                  * For handlers other than the default (supplied) handlers, we must
 242                  * exit the interpreter because the handler *might* block -- we don't
 243                  * know what it will do, so we can't hold the lock on the interpreter.
 244                  */
 245                 acpi_ex_exit_interpreter();
 246         }
 247
 248         /*
 249          * Special handling for generic_serial_bus and general_purpose_io:
 250          * There are three extra parameters that must be passed to the
 251          * handler via the context:
 252          *   1) Connection buffer, a resource template from Connection() op
 253          *   2) Length of the above buffer
 254          *   3) Actual access length from the access_as() op
 255          *
 256          * Since we pass these extra parameters via the context, which is
 257          * shared between threads, we must lock the context to avoid these
 258          * parameters being changed from another thread before the handler
 259          * has completed running.
 260          *
 261          * In addition, for general_purpose_io, the Address and bit_width fields
 262          * are defined as follows:
 263          *   1) Address is the pin number index of the field (bit offset from
 264          *      the previous Connection)
 265          *   2) bit_width is the actual bit length of the field (number of pins)
 266          */
 267         if ((region_obj->region.space_id == ACPI_ADR_SPACE_GSBUS ||
 268              region_obj->region.space_id == ACPI_ADR_SPACE_GPIO) &&
 269             context && field_obj) {
 270
 271                 status =
 272                     acpi_os_acquire_mutex(context_mutex, ACPI_WAIT_FOREVER);
 273                 if (ACPI_FAILURE(status)) {
 274                         goto re_enter_interpreter;
 275                 }
 276
 277                 context_locked = TRUE;
 278
 279                 /* Get the Connection (resource_template) buffer */
 280
 281                 context->connection = field_obj->field.resource_buffer;
 282                 context->length = field_obj->field.resource_length;
 283                 context->access_length = field_obj->field.access_length;
 284
 285                 if (region_obj->region.space_id == ACPI_ADR_SPACE_GPIO) {
 286                         address = field_obj->field.pin_number_index;
 287                         bit_width = field_obj->field.bit_length;
 288                 }
 289         }
 290
 291         /* Call the handler */
 292
 293         status = handler(function, address, bit_width, value, context,
 294                          region_obj2->extra.region_context);
 295
 296         if (context_locked) {
 297                 acpi_os_release_mutex(context_mutex);
 298         }
 299
 300         if (ACPI_FAILURE(status)) {
 301                 ACPI_EXCEPTION((AE_INFO, status, "Returned by Handler for [%s]",
 302                                 acpi_ut_get_region_name(region_obj->region.
 303                                                         space_id)));
 304
 305                 /*
 306                  * Special case for an EC timeout. These are seen so frequently
 307                  * that an additional error message is helpful
 308                  */
 309                 if ((region_obj->region.space_id == ACPI_ADR_SPACE_EC) &&
 310                     (status == AE_TIME)) {
 311                         ACPI_ERROR((AE_INFO,
 312                                     "Timeout from EC hardware or EC device driver"));
 313                 }
 314         }
 315
 316 re_enter_interpreter:
 317         if (!(handler_desc->address_space.handler_flags &
 318               ACPI_ADDR_HANDLER_DEFAULT_INSTALLED)) {
 319                 /*
 320                  * We just returned from a non-default handler, we must re-enter the
 321                  * interpreter
 322                  */
 323                 acpi_ex_enter_interpreter();
 324         }
 325
 326         return_ACPI_STATUS(status);
 327 }
 328
 329 /*******************************************************************************
 330  *
 331  * FUNCTION:    acpi_ev_detach_region
 332  *
 333  * PARAMETERS:  region_obj          - Region Object
 334  *              acpi_ns_is_locked   - Namespace Region Already Locked?
 335  *
 336  * RETURN:      None
 337  *
 338  * DESCRIPTION: Break the association between the handler and the region
 339  *              this is a two way association.
 340  *
 341  ******************************************************************************/
 342
 343 void
 344 acpi_ev_detach_region(union acpi_operand_object *region_obj,
 345                       u8 acpi_ns_is_locked)
 346 {
 347         union acpi_operand_object *handler_obj;
 348         union acpi_operand_object *obj_desc;
 349         union acpi_operand_object *start_desc;
 350         union acpi_operand_object **last_obj_ptr;
 351         acpi_adr_space_setup region_setup;
 352         void **region_context;
 353         union acpi_operand_object *region_obj2;
 354         acpi_status status;
 355
 356         ACPI_FUNCTION_TRACE(ev_detach_region);
 357
 358         region_obj2 = acpi_ns_get_secondary_object(region_obj);
 359         if (!region_obj2) {
 360                 return_VOID;
 361         }
 362         region_context = &region_obj2->extra.region_context;
 363
 364         /* Get the address handler from the region object */
 365
 366         handler_obj = region_obj->region.handler;
 367         if (!handler_obj) {
 368
 369                 /* This region has no handler, all done */
 370
 371                 return_VOID;
 372         }
 373
 374         /* Find this region in the handler's list */
 375
 376         obj_desc = handler_obj->address_space.region_list;
 377         start_desc = obj_desc;
 378         last_obj_ptr = &handler_obj->address_space.region_list;
 379
 380         while (obj_desc) {
 381
 382                 /* Is this the correct Region? */
 383
 384                 if (obj_desc == region_obj) {
 385                         ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
 386                                           "Removing Region %p from address handler %p\n",
 387                                           region_obj, handler_obj));
 388
 389                         /* This is it, remove it from the handler's list */
 390
 391                         *last_obj_ptr = obj_desc->region.next;
 392                         obj_desc->region.next = NULL;   /* Must clear field */
 393
 394                         if (acpi_ns_is_locked) {
 395                                 status =
 396                                     acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 397                                 if (ACPI_FAILURE(status)) {
 398                                         return_VOID;
 399                                 }
 400                         }
 401
 402                         /* Now stop region accesses by executing the _REG method */
 403
 404                         status =
 405                             acpi_ev_execute_reg_method(region_obj,
 406                                                        ACPI_REG_DISCONNECT);
 407                         if (ACPI_FAILURE(status)) {
 408                                 ACPI_EXCEPTION((AE_INFO, status,
 409                                                 "from region _REG, [%s]",
 410                                                 acpi_ut_get_region_name
 411                                                 (region_obj->region.space_id)));
 412                         }
 413
 414                         if (acpi_ns_is_locked) {
 415                                 status =
 416                                     acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 417                                 if (ACPI_FAILURE(status)) {
 418                                         return_VOID;
 419                                 }
 420                         }
 421
 422                         /*
 423                          * If the region has been activated, call the setup handler with
 424                          * the deactivate notification
 425                          */
 426                         if (region_obj->region.flags & AOPOBJ_SETUP_COMPLETE) {
 427                                 region_setup = handler_obj->address_space.setup;
 428                                 status =
 429                                     region_setup(region_obj,
 430                                                  ACPI_REGION_DEACTIVATE,
 431                                                  handler_obj->address_space.
 432                                                  context, region_context);
 433
 434                                 /*
 435                                  * region_context should have been released by the deactivate
 436                                  * operation. We don't need access to it anymore here.
 437                                  */
 438                                 if (region_context) {
 439                                         *region_context = NULL;
 440                                 }
 441
 442                                 /* Init routine may fail, Just ignore errors */
 443
 444                                 if (ACPI_FAILURE(status)) {
 445                                         ACPI_EXCEPTION((AE_INFO, status,
 446                                                         "from region handler - deactivate, [%s]",
 447                                                         acpi_ut_get_region_name
 448                                                         (region_obj->region.
 449                                                          space_id)));
 450                                 }
 451
 452                                 region_obj->region.flags &=
 453                                     ~(AOPOBJ_SETUP_COMPLETE);
 454                         }
 455
 456                         /*
 457                          * Remove handler reference in the region
 458                          *
 459                          * NOTE: this doesn't mean that the region goes away, the region
 460                          * is just inaccessible as indicated to the _REG method
 461                          *
 462                          * If the region is on the handler's list, this must be the
 463                          * region's handler
 464                          */
 465                         region_obj->region.handler = NULL;
 466                         acpi_ut_remove_reference(handler_obj);
 467
 468                         return_VOID;
 469                 }
 470
 471                 /* Walk the linked list of handlers */
 472
 473                 last_obj_ptr = &obj_desc->region.next;
 474                 obj_desc = obj_desc->region.next;
 475
 476                 /* Prevent infinite loop if list is corrupted */
 477
 478                 if (obj_desc == start_desc) {
 479                         ACPI_ERROR((AE_INFO,
 480                                     "Circular handler list in region object %p",
 481                                     region_obj));
 482                         return_VOID;
 483                 }
 484         }
 485
 486         /* If we get here, the region was not in the handler's region list */
 487
 488         ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
 489                           "Cannot remove region %p from address handler %p\n",
 490                           region_obj, handler_obj));
 491
 492         return_VOID;
 493 }
 494
 495 /*******************************************************************************
 496  *
 497  * FUNCTION:    acpi_ev_attach_region
 498  *
 499  * PARAMETERS:  handler_obj         - Handler Object
 500  *              region_obj          - Region Object
 501  *              acpi_ns_is_locked   - Namespace Region Already Locked?
 502  *
 503  * RETURN:      None
 504  *
 505  * DESCRIPTION: Create the association between the handler and the region
 506  *              this is a two way association.
 507  *
 508  ******************************************************************************/
 509
 510 acpi_status
 511 acpi_ev_attach_region(union acpi_operand_object *handler_obj,
 512                       union acpi_operand_object *region_obj,
 513                       u8 acpi_ns_is_locked)
 514 {
 515
 516         ACPI_FUNCTION_TRACE(ev_attach_region);
 517
 518         /* Install the region's handler */
 519
 520         if (region_obj->region.handler) {
 521                 return_ACPI_STATUS(AE_ALREADY_EXISTS);
 522         }
 523
 524         ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
 525                           "Adding Region [%4.4s] %p to address handler %p [%s]\n",
 526                           acpi_ut_get_node_name(region_obj->region.node),
 527                           region_obj, handler_obj,
 528                           acpi_ut_get_region_name(region_obj->region.
 529                                                   space_id)));
 530
 531         /* Link this region to the front of the handler's list */
 532
 533         region_obj->region.next = handler_obj->address_space.region_list;
 534         handler_obj->address_space.region_list = region_obj;
 535         region_obj->region.handler = handler_obj;
 536         acpi_ut_add_reference(handler_obj);
 537
 538         return_ACPI_STATUS(AE_OK);
 539 }
 540
 541 /*******************************************************************************
 542  *
 543  * FUNCTION:    acpi_ev_execute_reg_method
 544  *
 545  * PARAMETERS:  region_obj          - Region object
 546  *              function            - Passed to _REG: On (1) or Off (0)
 547  *
 548  * RETURN:      Status
 549  *
 550  * DESCRIPTION: Execute _REG method for a region
 551  *
 552  ******************************************************************************/
 553
 554 acpi_status
 555 acpi_ev_execute_reg_method(union acpi_operand_object *region_obj, u32 function)
 556 {
 557         struct acpi_evaluate_info *info;
 558         union acpi_operand_object *args[3];
 559         union acpi_operand_object *region_obj2;
 560         const acpi_name *reg_name_ptr =
 561             ACPI_CAST_PTR(acpi_name, METHOD_NAME__REG);
 562         struct acpi_namespace_node *method_node;
 563         struct acpi_namespace_node *node;
 564         acpi_status status;
 565
 566         ACPI_FUNCTION_TRACE(ev_execute_reg_method);
 567
 568         if (!acpi_gbl_namespace_initialized ||
 569             region_obj->region.handler == NULL) {
 570                 return_ACPI_STATUS(AE_OK);
 571         }
 572
 573         region_obj2 = acpi_ns_get_secondary_object(region_obj);
 574         if (!region_obj2) {
 575                 return_ACPI_STATUS(AE_NOT_EXIST);
 576         }
 577
 578         /*
 579          * Find any "_REG" method associated with this region definition.
 580          * The method should always be updated as this function may be
 581          * invoked after a namespace change.
 582          */
 583         node = region_obj->region.node->parent;
 584         status =
 585             acpi_ns_search_one_scope(*reg_name_ptr, node, ACPI_TYPE_METHOD,
 586                                      &method_node);
 587         if (ACPI_SUCCESS(status)) {
 588                 /*
 589                  * The _REG method is optional and there can be only one per
 590                  * region definition. This will be executed when the handler is
 591                  * attached or removed.
 592                  */
 593                 region_obj2->extra.method_REG = method_node;
 594         }
 595         if (region_obj2->extra.method_REG == NULL) {
 596                 return_ACPI_STATUS(AE_OK);
 597         }
 598
 599         /* _REG(DISCONNECT) should be paired with _REG(CONNECT) */
 600
 601         if ((function == ACPI_REG_CONNECT &&
 602              region_obj->common.flags & AOPOBJ_REG_CONNECTED) ||
 603             (function == ACPI_REG_DISCONNECT &&
 604              !(region_obj->common.flags & AOPOBJ_REG_CONNECTED))) {
 605                 return_ACPI_STATUS(AE_OK);
 606         }
 607
 608         /* Allocate and initialize the evaluation information block */
 609
 610         info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
 611         if (!info) {
 612                 return_ACPI_STATUS(AE_NO_MEMORY);
 613         }
 614
 615         info->prefix_node = region_obj2->extra.method_REG;
 616         info->relative_pathname = NULL;
 617         info->parameters = args;
 618         info->flags = ACPI_IGNORE_RETURN_VALUE;
 619
 620         /*
 621          * The _REG method has two arguments:
 622          *
 623          * arg0 - Integer:
 624          *  Operation region space ID Same value as region_obj->Region.space_id
 625          *
 626          * arg1 - Integer:
 627          *  connection status 1 for connecting the handler, 0 for disconnecting
 628          *  the handler (Passed as a parameter)
 629          */
 630         args[0] =
 631             acpi_ut_create_integer_object((u64)region_obj->region.space_id);
 632         if (!args[0]) {
 633                 status = AE_NO_MEMORY;
 634                 goto cleanup1;
 635         }
 636
 637         args[1] = acpi_ut_create_integer_object((u64)function);
 638         if (!args[1]) {
 639                 status = AE_NO_MEMORY;
 640                 goto cleanup2;
 641         }
 642
 643         args[2] = NULL;         /* Terminate list */
 644
 645         /* Execute the method, no return value */
 646
 647         ACPI_DEBUG_EXEC(acpi_ut_display_init_pathname
 648                         (ACPI_TYPE_METHOD, info->prefix_node, NULL));
 649
 650         status = acpi_ns_evaluate(info);
 651         acpi_ut_remove_reference(args[1]);
 652
 653         if (ACPI_FAILURE(status)) {
 654                 goto cleanup2;
 655         }
 656
 657         if (function == ACPI_REG_CONNECT) {
 658                 region_obj->common.flags |= AOPOBJ_REG_CONNECTED;
 659         } else {
 660                 region_obj->common.flags &= ~AOPOBJ_REG_CONNECTED;
 661         }
 662
 663 cleanup2:
 664         acpi_ut_remove_reference(args[0]);
 665
 666 cleanup1:
 667         ACPI_FREE(info);
 668         return_ACPI_STATUS(status);
 669 }
 670
 671 /*******************************************************************************
 672  *
 673  * FUNCTION:    acpi_ev_execute_reg_methods
 674  *
 675  * PARAMETERS:  node            - Namespace node for the device
 676  *              max_depth       - Depth to which search for _REG
 677  *              space_id        - The address space ID
 678  *              function        - Passed to _REG: On (1) or Off (0)
 679  *
 680  * RETURN:      None
 681  *
 682  * DESCRIPTION: Run all _REG methods for the input Space ID;
 683  *              Note: assumes namespace is locked, or system init time.
 684  *
 685  ******************************************************************************/
 686
 687 void
 688 acpi_ev_execute_reg_methods(struct acpi_namespace_node *node, u32 max_depth,
 689                             acpi_adr_space_type space_id, u32 function)
 690 {
 691         struct acpi_reg_walk_info info;
 692
 693         ACPI_FUNCTION_TRACE(ev_execute_reg_methods);
 694
 695         /*
 696          * These address spaces do not need a call to _REG, since the ACPI
 697          * specification defines them as: "must always be accessible". Since
 698          * they never change state (never become unavailable), no need to ever
 699          * call _REG on them. Also, a data_table is not a "real" address space,
 700          * so do not call _REG. September 2018.
 701          */
 702         if ((space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY) ||
 703             (space_id == ACPI_ADR_SPACE_SYSTEM_IO) ||
 704             (space_id == ACPI_ADR_SPACE_DATA_TABLE)) {
 705                 return_VOID;
 706         }
 707
 708         info.space_id = space_id;
 709         info.function = function;
 710         info.reg_run_count = 0;
 711
 712         ACPI_DEBUG_PRINT_RAW((ACPI_DB_NAMES,
 713                               "    Running _REG methods for SpaceId %s\n",
 714                               acpi_ut_get_region_name(info.space_id)));
 715
 716         /*
 717          * Run all _REG methods for all Operation Regions for this space ID. This
 718          * is a separate walk in order to handle any interdependencies between
 719          * regions and _REG methods. (i.e. handlers must be installed for all
 720          * regions of this Space ID before we can run any _REG methods)
 721          */
 722         (void)acpi_ns_walk_namespace(ACPI_TYPE_ANY, node, max_depth,
 723                                      ACPI_NS_WALK_UNLOCK, acpi_ev_reg_run, NULL,
 724                                      &info, NULL);
 725
 726         /*
 727          * Special case for EC and GPIO: handle "orphan" _REG methods with
 728          * no region.
 729          */
 730         if (space_id == ACPI_ADR_SPACE_EC || space_id == ACPI_ADR_SPACE_GPIO) {
 731                 acpi_ev_execute_orphan_reg_method(node, space_id);
 732         }
 733
 734         ACPI_DEBUG_PRINT_RAW((ACPI_DB_NAMES,
 735                               "    Executed %u _REG methods for SpaceId %s\n",
 736                               info.reg_run_count,
 737                               acpi_ut_get_region_name(info.space_id)));
 738
 739         return_VOID;
 740 }
 741
 742 /*******************************************************************************
 743  *
 744  * FUNCTION:    acpi_ev_reg_run
 745  *
 746  * PARAMETERS:  walk_namespace callback
 747  *
 748  * DESCRIPTION: Run _REG method for region objects of the requested spaceID
 749  *
 750  ******************************************************************************/
 751
 752 static acpi_status
 753 acpi_ev_reg_run(acpi_handle obj_handle,
 754                 u32 level, void *context, void **return_value)
 755 {
 756         union acpi_operand_object *obj_desc;
 757         struct acpi_namespace_node *node;
 758         acpi_status status;
 759         struct acpi_reg_walk_info *info;
 760
 761         info = ACPI_CAST_PTR(struct acpi_reg_walk_info, context);
 762
 763         /* Convert and validate the device handle */
 764
 765         node = acpi_ns_validate_handle(obj_handle);
 766         if (!node) {
 767                 return (AE_BAD_PARAMETER);
 768         }
 769
 770         /*
 771          * We only care about regions and objects that are allowed to have
 772          * address space handlers
 773          */
 774         if ((node->type != ACPI_TYPE_REGION) && (node != acpi_gbl_root_node)) {
 775                 return (AE_OK);
 776         }
 777
 778         /* Check for an existing internal object */
 779
 780         obj_desc = acpi_ns_get_attached_object(node);
 781         if (!obj_desc) {
 782
 783                 /* No object, just exit */
 784
 785                 return (AE_OK);
 786         }
 787
 788         /* Object is a Region */
 789
 790         if (obj_desc->region.space_id != info->space_id) {
 791
 792                 /* This region is for a different address space, just ignore it */
 793
 794                 return (AE_OK);
 795         }
 796
 797         info->reg_run_count++;
 798         status = acpi_ev_execute_reg_method(obj_desc, info->function);
 799         return (status);
 800 }
 801
 802 /*******************************************************************************
 803  *
 804  * FUNCTION:    acpi_ev_execute_orphan_reg_method
 805  *
 806  * PARAMETERS:  device_node         - Namespace node for an ACPI device
 807  *              space_id            - The address space ID
 808  *
 809  * RETURN:      None
 810  *
 811  * DESCRIPTION: Execute an "orphan" _REG method that appears under an ACPI
 812  *              device. This is a _REG method that has no corresponding region
 813  *              within the device's scope. ACPI tables depending on these
 814  *              "orphan" _REG methods have been seen for both EC and GPIO
 815  *              Operation Regions. Presumably the Windows ACPI implementation
 816  *              always calls the _REG method independent of the presence of
 817  *              an actual Operation Region with the correct address space ID.
 818  *
 819  *  MUTEX:      Assumes the namespace is locked
 820  *
 821  ******************************************************************************/
 822
 823 static void
 824 acpi_ev_execute_orphan_reg_method(struct acpi_namespace_node *device_node,
 825                                   acpi_adr_space_type space_id)
 826 {
 827         acpi_handle reg_method;
 828         struct acpi_namespace_node *next_node;
 829         acpi_status status;
 830         struct acpi_object_list args;
 831         union acpi_object objects[2];
 832
 833         ACPI_FUNCTION_TRACE(ev_execute_orphan_reg_method);
 834
 835         if (!device_node) {
 836                 return_VOID;
 837         }
 838
 839         /* Namespace is currently locked, must release */
 840
 841         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 842
 843         /* Get a handle to a _REG method immediately under the EC device */
 844
 845         status = acpi_get_handle(device_node, METHOD_NAME__REG, &reg_method);
 846         if (ACPI_FAILURE(status)) {
 847                 goto exit;      /* There is no _REG method present */
 848         }
 849
 850         /*
 851          * Execute the _REG method only if there is no Operation Region in
 852          * this scope with the Embedded Controller space ID. Otherwise, it
 853          * will already have been executed. Note, this allows for Regions
 854          * with other space IDs to be present; but the code below will then
 855          * execute the _REG method with the embedded_control space_ID argument.
 856          */
 857         next_node = acpi_ns_get_next_node(device_node, NULL);
 858         while (next_node) {
 859                 if ((next_node->type == ACPI_TYPE_REGION) &&
 860                     (next_node->object) &&
 861                     (next_node->object->region.space_id == space_id)) {
 862                         goto exit;      /* Do not execute the _REG */
 863                 }
 864
 865                 next_node = acpi_ns_get_next_node(device_node, next_node);
 866         }
 867
 868         /* Evaluate the _REG(space_id,Connect) method */
 869
 870         args.count = 2;
 871         args.pointer = objects;
 872         objects[0].type = ACPI_TYPE_INTEGER;
 873         objects[0].integer.value = space_id;
 874         objects[1].type = ACPI_TYPE_INTEGER;
 875         objects[1].integer.value = ACPI_REG_CONNECT;
 876
 877         (void)acpi_evaluate_object(reg_method, NULL, &args, NULL);
 878
 879 exit:
 880         /* We ignore all errors from above, don't care */
 881
 882         (void)acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 883         return_VOID;
 884 }