drivers/acpi/acpica/dsopcode.c

   1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
   2 /******************************************************************************
   3  *
   4  * Module Name: dsopcode - Dispatcher support for regions and fields
   5  *
   6  * Copyright (C) 2000 - 2018, Intel Corp.
   7  *
   8  *****************************************************************************/
   9
  10 #include <acpi/acpi.h>
  11 #include "accommon.h"
  12 #include "acparser.h"
  13 #include "amlcode.h"
  14 #include "acdispat.h"
  15 #include "acinterp.h"
  16 #include "acnamesp.h"
  17 #include "acevents.h"
  18 #include "actables.h"
  19
  20 #define _COMPONENT          ACPI_DISPATCHER
  21 ACPI_MODULE_NAME("dsopcode")
  22
  23 /* Local prototypes */
  24 static acpi_status
  25 acpi_ds_init_buffer_field(u16 aml_opcode,
  26                           union acpi_operand_object *obj_desc,
  27                           union acpi_operand_object *buffer_desc,
  28                           union acpi_operand_object *offset_desc,
  29                           union acpi_operand_object *length_desc,
  30                           union acpi_operand_object *result_desc);
  31
  32 /*******************************************************************************
  33  *
  34  * FUNCTION:    acpi_ds_initialize_region
  35  *
  36  * PARAMETERS:  obj_handle      - Region namespace node
  37  *
  38  * RETURN:      Status
  39  *
  40  * DESCRIPTION: Front end to ev_initialize_region
  41  *
  42  ******************************************************************************/
  43
  44 acpi_status acpi_ds_initialize_region(acpi_handle obj_handle)
  45 {
  46         union acpi_operand_object *obj_desc;
  47         acpi_status status;
  48
  49         obj_desc = acpi_ns_get_attached_object(obj_handle);
  50
  51         /* Namespace is NOT locked */
  52
  53         status = acpi_ev_initialize_region(obj_desc);
  54         return (status);
  55 }
  56
  57 /*******************************************************************************
  58  *
  59  * FUNCTION:    acpi_ds_init_buffer_field
  60  *
  61  * PARAMETERS:  aml_opcode      - create_xxx_field
  62  *              obj_desc        - buffer_field object
  63  *              buffer_desc     - Host Buffer
  64  *              offset_desc     - Offset into buffer
  65  *              length_desc     - Length of field (CREATE_FIELD_OP only)
  66  *              result_desc     - Where to store the result
  67  *
  68  * RETURN:      Status
  69  *
  70  * DESCRIPTION: Perform actual initialization of a buffer field
  71  *
  72  ******************************************************************************/
  73
  74 static acpi_status
  75 acpi_ds_init_buffer_field(u16 aml_opcode,
  76                           union acpi_operand_object *obj_desc,
  77                           union acpi_operand_object *buffer_desc,
  78                           union acpi_operand_object *offset_desc,
  79                           union acpi_operand_object *length_desc,
  80                           union acpi_operand_object *result_desc)
  81 {
  82         u32 offset;
  83         u32 bit_offset;
  84         u32 bit_count;
  85         u8 field_flags;
  86         acpi_status status;
  87
  88         ACPI_FUNCTION_TRACE_PTR(ds_init_buffer_field, obj_desc);
  89
  90         /* Host object must be a Buffer */
  91
  92         if (buffer_desc->common.type != ACPI_TYPE_BUFFER) {
  93                 ACPI_ERROR((AE_INFO,
  94                             "Target of Create Field is not a Buffer object - %s",
  95                             acpi_ut_get_object_type_name(buffer_desc)));
  96
  97                 status = AE_AML_OPERAND_TYPE;
  98                 goto cleanup;
  99         }
 100
 101         /*
 102          * The last parameter to all of these opcodes (result_desc) started
 103          * out as a name_string, and should therefore now be a NS node
 104          * after resolution in acpi_ex_resolve_operands().
 105          */
 106         if (ACPI_GET_DESCRIPTOR_TYPE(result_desc) != ACPI_DESC_TYPE_NAMED) {
 107                 ACPI_ERROR((AE_INFO,
 108                             "(%s) destination not a NS Node [%s]",
 109                             acpi_ps_get_opcode_name(aml_opcode),
 110                             acpi_ut_get_descriptor_name(result_desc)));
 111
 112                 status = AE_AML_OPERAND_TYPE;
 113                 goto cleanup;
 114         }
 115
 116         offset = (u32) offset_desc->integer.value;
 117
 118         /*
 119          * Setup the Bit offsets and counts, according to the opcode
 120          */
 121         switch (aml_opcode) {
 122         case AML_CREATE_FIELD_OP:
 123
 124                 /* Offset is in bits, count is in bits */
 125
 126                 field_flags = AML_FIELD_ACCESS_BYTE;
 127                 bit_offset = offset;
 128                 bit_count = (u32) length_desc->integer.value;
 129
 130                 /* Must have a valid (>0) bit count */
 131
 132                 if (bit_count == 0) {
 133                         ACPI_BIOS_ERROR((AE_INFO,
 134                                          "Attempt to CreateField of length zero"));
 135                         status = AE_AML_OPERAND_VALUE;
 136                         goto cleanup;
 137                 }
 138                 break;
 139
 140         case AML_CREATE_BIT_FIELD_OP:
 141
 142                 /* Offset is in bits, Field is one bit */
 143
 144                 bit_offset = offset;
 145                 bit_count = 1;
 146                 field_flags = AML_FIELD_ACCESS_BYTE;
 147                 break;
 148
 149         case AML_CREATE_BYTE_FIELD_OP:
 150
 151                 /* Offset is in bytes, field is one byte */
 152
 153                 bit_offset = 8 * offset;
 154                 bit_count = 8;
 155                 field_flags = AML_FIELD_ACCESS_BYTE;
 156                 break;
 157
 158         case AML_CREATE_WORD_FIELD_OP:
 159
 160                 /* Offset is in bytes, field is one word */
 161
 162                 bit_offset = 8 * offset;
 163                 bit_count = 16;
 164                 field_flags = AML_FIELD_ACCESS_WORD;
 165                 break;
 166
 167         case AML_CREATE_DWORD_FIELD_OP:
 168
 169                 /* Offset is in bytes, field is one dword */
 170
 171                 bit_offset = 8 * offset;
 172                 bit_count = 32;
 173                 field_flags = AML_FIELD_ACCESS_DWORD;
 174                 break;
 175
 176         case AML_CREATE_QWORD_FIELD_OP:
 177
 178                 /* Offset is in bytes, field is one qword */
 179
 180                 bit_offset = 8 * offset;
 181                 bit_count = 64;
 182                 field_flags = AML_FIELD_ACCESS_QWORD;
 183                 break;
 184
 185         default:
 186
 187                 ACPI_ERROR((AE_INFO,
 188                             "Unknown field creation opcode 0x%02X",
 189                             aml_opcode));
 190                 status = AE_AML_BAD_OPCODE;
 191                 goto cleanup;
 192         }
 193
 194         /* Entire field must fit within the current length of the buffer */
 195
 196         if ((bit_offset + bit_count) > (8 * (u32)buffer_desc->buffer.length)) {
 197                 status = AE_AML_BUFFER_LIMIT;
 198                 ACPI_BIOS_EXCEPTION((AE_INFO, status,
 199                                      "Field [%4.4s] at bit offset/length %u/%u "
 200                                      "exceeds size of target Buffer (%u bits)",
 201                                      acpi_ut_get_node_name(result_desc),
 202                                      bit_offset, bit_count,
 203                                      8 * (u32)buffer_desc->buffer.length));
 204                 goto cleanup;
 205         }
 206
 207         /*
 208          * Initialize areas of the field object that are common to all fields
 209          * For field_flags, use LOCK_RULE = 0 (NO_LOCK),
 210          * UPDATE_RULE = 0 (UPDATE_PRESERVE)
 211          */
 212         status =
 213             acpi_ex_prep_common_field_object(obj_desc, field_flags, 0,
 214                                              bit_offset, bit_count);
 215         if (ACPI_FAILURE(status)) {
 216                 goto cleanup;
 217         }
 218
 219         obj_desc->buffer_field.buffer_obj = buffer_desc;
 220
 221         /* Reference count for buffer_desc inherits obj_desc count */
 222
 223         buffer_desc->common.reference_count = (u16)
 224             (buffer_desc->common.reference_count +
 225              obj_desc->common.reference_count);
 226
 227 cleanup:
 228
 229         /* Always delete the operands */
 230
 231         acpi_ut_remove_reference(offset_desc);
 232         acpi_ut_remove_reference(buffer_desc);
 233
 234         if (aml_opcode == AML_CREATE_FIELD_OP) {
 235                 acpi_ut_remove_reference(length_desc);
 236         }
 237
 238         /* On failure, delete the result descriptor */
 239
 240         if (ACPI_FAILURE(status)) {
 241                 acpi_ut_remove_reference(result_desc);  /* Result descriptor */
 242         } else {
 243                 /* Now the address and length are valid for this buffer_field */
 244
 245                 obj_desc->buffer_field.flags |= AOPOBJ_DATA_VALID;
 246         }
 247
 248         return_ACPI_STATUS(status);
 249 }
 250
 251 /*******************************************************************************
 252  *
 253  * FUNCTION:    acpi_ds_eval_buffer_field_operands
 254  *
 255  * PARAMETERS:  walk_state      - Current walk
 256  *              op              - A valid buffer_field Op object
 257  *
 258  * RETURN:      Status
 259  *
 260  * DESCRIPTION: Get buffer_field Buffer and Index
 261  *              Called from acpi_ds_exec_end_op during buffer_field parse tree walk
 262  *
 263  ******************************************************************************/
 264
 265 acpi_status
 266 acpi_ds_eval_buffer_field_operands(struct acpi_walk_state *walk_state,
 267                                    union acpi_parse_object *op)
 268 {
 269         acpi_status status;
 270         union acpi_operand_object *obj_desc;
 271         struct acpi_namespace_node *node;
 272         union acpi_parse_object *next_op;
 273
 274         ACPI_FUNCTION_TRACE_PTR(ds_eval_buffer_field_operands, op);
 275
 276         /*
 277          * This is where we evaluate the address and length fields of the
 278          * create_xxx_field declaration
 279          */
 280         node = op->common.node;
 281
 282         /* next_op points to the op that holds the Buffer */
 283
 284         next_op = op->common.value.arg;
 285
 286         /* Evaluate/create the address and length operands */
 287
 288         status = acpi_ds_create_operands(walk_state, next_op);
 289         if (ACPI_FAILURE(status)) {
 290                 return_ACPI_STATUS(status);
 291         }
 292
 293         obj_desc = acpi_ns_get_attached_object(node);
 294         if (!obj_desc) {
 295                 return_ACPI_STATUS(AE_NOT_EXIST);
 296         }
 297
 298         /* Resolve the operands */
 299
 300         status =
 301             acpi_ex_resolve_operands(op->common.aml_opcode, ACPI_WALK_OPERANDS,
 302                                      walk_state);
 303         if (ACPI_FAILURE(status)) {
 304                 ACPI_ERROR((AE_INFO, "(%s) bad operand(s), status 0x%X",
 305                             acpi_ps_get_opcode_name(op->common.aml_opcode),
 306                             status));
 307
 308                 return_ACPI_STATUS(status);
 309         }
 310
 311         /* Initialize the Buffer Field */
 312
 313         if (op->common.aml_opcode == AML_CREATE_FIELD_OP) {
 314
 315                 /* NOTE: Slightly different operands for this opcode */
 316
 317                 status =
 318                     acpi_ds_init_buffer_field(op->common.aml_opcode, obj_desc,
 319                                               walk_state->operands[0],
 320                                               walk_state->operands[1],
 321                                               walk_state->operands[2],
 322                                               walk_state->operands[3]);
 323         } else {
 324                 /* All other, create_xxx_field opcodes */
 325
 326                 status =
 327                     acpi_ds_init_buffer_field(op->common.aml_opcode, obj_desc,
 328                                               walk_state->operands[0],
 329                                               walk_state->operands[1], NULL,
 330                                               walk_state->operands[2]);
 331         }
 332
 333         return_ACPI_STATUS(status);
 334 }
 335
 336 /*******************************************************************************
 337  *
 338  * FUNCTION:    acpi_ds_eval_region_operands
 339  *
 340  * PARAMETERS:  walk_state      - Current walk
 341  *              op              - A valid region Op object
 342  *
 343  * RETURN:      Status
 344  *
 345  * DESCRIPTION: Get region address and length
 346  *              Called from acpi_ds_exec_end_op during op_region parse tree walk
 347  *
 348  ******************************************************************************/
 349
 350 acpi_status
 351 acpi_ds_eval_region_operands(struct acpi_walk_state *walk_state,
 352                              union acpi_parse_object *op)
 353 {
 354         acpi_status status;
 355         union acpi_operand_object *obj_desc;
 356         union acpi_operand_object *operand_desc;
 357         struct acpi_namespace_node *node;
 358         union acpi_parse_object *next_op;
 359
 360         ACPI_FUNCTION_TRACE_PTR(ds_eval_region_operands, op);
 361
 362         /*
 363          * This is where we evaluate the address and length fields of the
 364          * op_region declaration
 365          */
 366         node = op->common.node;
 367
 368         /* next_op points to the op that holds the space_ID */
 369
 370         next_op = op->common.value.arg;
 371
 372         /* next_op points to address op */
 373
 374         next_op = next_op->common.next;
 375
 376         /* Evaluate/create the address and length operands */
 377
 378         status = acpi_ds_create_operands(walk_state, next_op);
 379         if (ACPI_FAILURE(status)) {
 380                 return_ACPI_STATUS(status);
 381         }
 382
 383         /* Resolve the length and address operands to numbers */
 384
 385         status =
 386             acpi_ex_resolve_operands(op->common.aml_opcode, ACPI_WALK_OPERANDS,
 387                                      walk_state);
 388         if (ACPI_FAILURE(status)) {
 389                 return_ACPI_STATUS(status);
 390         }
 391
 392         obj_desc = acpi_ns_get_attached_object(node);
 393         if (!obj_desc) {
 394                 return_ACPI_STATUS(AE_NOT_EXIST);
 395         }
 396
 397         /*
 398          * Get the length operand and save it
 399          * (at Top of stack)
 400          */
 401         operand_desc = walk_state->operands[walk_state->num_operands - 1];
 402
 403         obj_desc->region.length = (u32) operand_desc->integer.value;
 404         acpi_ut_remove_reference(operand_desc);
 405
 406         /*
 407          * Get the address and save it
 408          * (at top of stack - 1)
 409          */
 410         operand_desc = walk_state->operands[walk_state->num_operands - 2];
 411
 412         obj_desc->region.address = (acpi_physical_address)
 413             operand_desc->integer.value;
 414         acpi_ut_remove_reference(operand_desc);
 415
 416         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "RgnObj %p Addr %8.8X%8.8X Len %X\n",
 417                           obj_desc,
 418                           ACPI_FORMAT_UINT64(obj_desc->region.address),
 419                           obj_desc->region.length));
 420
 421         status = acpi_ut_add_address_range(obj_desc->region.space_id,
 422                                            obj_desc->region.address,
 423                                            obj_desc->region.length, node);
 424
 425         /* Now the address and length are valid for this opregion */
 426
 427         obj_desc->region.flags |= AOPOBJ_DATA_VALID;
 428         return_ACPI_STATUS(status);
 429 }
 430
 431 /*******************************************************************************
 432  *
 433  * FUNCTION:    acpi_ds_eval_table_region_operands
 434  *
 435  * PARAMETERS:  walk_state      - Current walk
 436  *              op              - A valid region Op object
 437  *
 438  * RETURN:      Status
 439  *
 440  * DESCRIPTION: Get region address and length.
 441  *              Called from acpi_ds_exec_end_op during data_table_region parse
 442  *              tree walk.
 443  *
 444  ******************************************************************************/
 445
 446 acpi_status
 447 acpi_ds_eval_table_region_operands(struct acpi_walk_state *walk_state,
 448                                    union acpi_parse_object *op)
 449 {
 450         acpi_status status;
 451         union acpi_operand_object *obj_desc;
 452         union acpi_operand_object **operand;
 453         struct acpi_namespace_node *node;
 454         union acpi_parse_object *next_op;
 455         struct acpi_table_header *table;
 456         u32 table_index;
 457
 458         ACPI_FUNCTION_TRACE_PTR(ds_eval_table_region_operands, op);
 459
 460         /*
 461          * This is where we evaluate the Signature string, oem_id string,
 462          * and oem_table_id string of the Data Table Region declaration
 463          */
 464         node = op->common.node;
 465
 466         /* next_op points to Signature string op */
 467
 468         next_op = op->common.value.arg;
 469
 470         /*
 471          * Evaluate/create the Signature string, oem_id string,
 472          * and oem_table_id string operands
 473          */
 474         status = acpi_ds_create_operands(walk_state, next_op);
 475         if (ACPI_FAILURE(status)) {
 476                 return_ACPI_STATUS(status);
 477         }
 478
 479         operand = &walk_state->operands[0];
 480
 481         /*
 482          * Resolve the Signature string, oem_id string,
 483          * and oem_table_id string operands
 484          */
 485         status =
 486             acpi_ex_resolve_operands(op->common.aml_opcode, ACPI_WALK_OPERANDS,
 487                                      walk_state);
 488         if (ACPI_FAILURE(status)) {
 489                 goto cleanup;
 490         }
 491
 492         /* Find the ACPI table */
 493
 494         status = acpi_tb_find_table(operand[0]->string.pointer,
 495                                     operand[1]->string.pointer,
 496                                     operand[2]->string.pointer, &table_index);
 497         if (ACPI_FAILURE(status)) {
 498                 if (status == AE_NOT_FOUND) {
 499                         ACPI_ERROR((AE_INFO,
 500                                     "ACPI Table [%4.4s] OEM:(%s, %s) not found in RSDT/XSDT",
 501                                     operand[0]->string.pointer,
 502                                     operand[1]->string.pointer,
 503                                     operand[2]->string.pointer));
 504                 }
 505                 goto cleanup;
 506         }
 507
 508         status = acpi_get_table_by_index(table_index, &table);
 509         if (ACPI_FAILURE(status)) {
 510                 goto cleanup;
 511         }
 512
 513         obj_desc = acpi_ns_get_attached_object(node);
 514         if (!obj_desc) {
 515                 status = AE_NOT_EXIST;
 516                 goto cleanup;
 517         }
 518
 519         obj_desc->region.address = ACPI_PTR_TO_PHYSADDR(table);
 520         obj_desc->region.length = table->length;
 521
 522         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "RgnObj %p Addr %8.8X%8.8X Len %X\n",
 523                           obj_desc,
 524                           ACPI_FORMAT_UINT64(obj_desc->region.address),
 525                           obj_desc->region.length));
 526
 527         /* Now the address and length are valid for this opregion */
 528
 529         obj_desc->region.flags |= AOPOBJ_DATA_VALID;
 530
 531 cleanup:
 532         acpi_ut_remove_reference(operand[0]);
 533         acpi_ut_remove_reference(operand[1]);
 534         acpi_ut_remove_reference(operand[2]);
 535
 536         return_ACPI_STATUS(status);
 537 }
 538
 539 /*******************************************************************************
 540  *
 541  * FUNCTION:    acpi_ds_eval_data_object_operands
 542  *
 543  * PARAMETERS:  walk_state      - Current walk
 544  *              op              - A valid data_object Op object
 545  *              obj_desc        - data_object
 546  *
 547  * RETURN:      Status
 548  *
 549  * DESCRIPTION: Get the operands and complete the following data object types:
 550  *              Buffer, Package.
 551  *
 552  ******************************************************************************/
 553
 554 acpi_status
 555 acpi_ds_eval_data_object_operands(struct acpi_walk_state *walk_state,
 556                                   union acpi_parse_object *op,
 557                                   union acpi_operand_object *obj_desc)
 558 {
 559         acpi_status status;
 560         union acpi_operand_object *arg_desc;
 561         u32 length;
 562
 563         ACPI_FUNCTION_TRACE(ds_eval_data_object_operands);
 564
 565         /* The first operand (for all of these data objects) is the length */
 566
 567         /*
 568          * Set proper index into operand stack for acpi_ds_obj_stack_push
 569          * invoked inside acpi_ds_create_operand.
 570          */
 571         walk_state->operand_index = walk_state->num_operands;
 572
 573         /* Ignore if child is not valid */
 574
 575         if (!op->common.value.arg) {
 576                 ACPI_ERROR((AE_INFO,
 577                             "Missing child while evaluating opcode %4.4X, Op %p",
 578                             op->common.aml_opcode, op));
 579                 return_ACPI_STATUS(AE_OK);
 580         }
 581
 582         status = acpi_ds_create_operand(walk_state, op->common.value.arg, 1);
 583         if (ACPI_FAILURE(status)) {
 584                 return_ACPI_STATUS(status);
 585         }
 586
 587         status = acpi_ex_resolve_operands(walk_state->opcode,
 588                                           &(walk_state->
 589                                             operands[walk_state->num_operands -
 590                                                      1]), walk_state);
 591         if (ACPI_FAILURE(status)) {
 592                 return_ACPI_STATUS(status);
 593         }
 594
 595         /* Extract length operand */
 596
 597         arg_desc = walk_state->operands[walk_state->num_operands - 1];
 598         length = (u32) arg_desc->integer.value;
 599
 600         /* Cleanup for length operand */
 601
 602         status = acpi_ds_obj_stack_pop(1, walk_state);
 603         if (ACPI_FAILURE(status)) {
 604                 return_ACPI_STATUS(status);
 605         }
 606
 607         acpi_ut_remove_reference(arg_desc);
 608
 609         /*
 610          * Create the actual data object
 611          */
 612         switch (op->common.aml_opcode) {
 613         case AML_BUFFER_OP:
 614
 615                 status =
 616                     acpi_ds_build_internal_buffer_obj(walk_state, op, length,
 617                                                       &obj_desc);
 618                 break;
 619
 620         case AML_PACKAGE_OP:
 621         case AML_VARIABLE_PACKAGE_OP:
 622
 623                 status =
 624                     acpi_ds_build_internal_package_obj(walk_state, op, length,
 625                                                        &obj_desc);
 626                 break;
 627
 628         default:
 629
 630                 return_ACPI_STATUS(AE_AML_BAD_OPCODE);
 631         }
 632
 633         if (ACPI_SUCCESS(status)) {
 634                 /*
 635                  * Return the object in the walk_state, unless the parent is a package -
 636                  * in this case, the return object will be stored in the parse tree
 637                  * for the package.
 638                  */
 639                 if ((!op->common.parent) ||
 640                     ((op->common.parent->common.aml_opcode != AML_PACKAGE_OP) &&
 641                      (op->common.parent->common.aml_opcode !=
 642                       AML_VARIABLE_PACKAGE_OP)
 643                      && (op->common.parent->common.aml_opcode !=
 644                          AML_NAME_OP))) {
 645                         walk_state->result_obj = obj_desc;
 646                 }
 647         }
 648
 649         return_ACPI_STATUS(status);
 650 }
 651
 652 /*******************************************************************************
 653  *
 654  * FUNCTION:    acpi_ds_eval_bank_field_operands
 655  *
 656  * PARAMETERS:  walk_state      - Current walk
 657  *              op              - A valid bank_field Op object
 658  *
 659  * RETURN:      Status
 660  *
 661  * DESCRIPTION: Get bank_field bank_value
 662  *              Called from acpi_ds_exec_end_op during bank_field parse tree walk
 663  *
 664  ******************************************************************************/
 665
 666 acpi_status
 667 acpi_ds_eval_bank_field_operands(struct acpi_walk_state *walk_state,
 668                                  union acpi_parse_object *op)
 669 {
 670         acpi_status status;
 671         union acpi_operand_object *obj_desc;
 672         union acpi_operand_object *operand_desc;
 673         struct acpi_namespace_node *node;
 674         union acpi_parse_object *next_op;
 675         union acpi_parse_object *arg;
 676
 677         ACPI_FUNCTION_TRACE_PTR(ds_eval_bank_field_operands, op);
 678
 679         /*
 680          * This is where we evaluate the bank_value field of the
 681          * bank_field declaration
 682          */
 683
 684         /* next_op points to the op that holds the Region */
 685
 686         next_op = op->common.value.arg;
 687
 688         /* next_op points to the op that holds the Bank Register */
 689
 690         next_op = next_op->common.next;
 691
 692         /* next_op points to the op that holds the Bank Value */
 693
 694         next_op = next_op->common.next;
 695
 696         /*
 697          * Set proper index into operand stack for acpi_ds_obj_stack_push
 698          * invoked inside acpi_ds_create_operand.
 699          *
 700          * We use walk_state->Operands[0] to store the evaluated bank_value
 701          */
 702         walk_state->operand_index = 0;
 703
 704         status = acpi_ds_create_operand(walk_state, next_op, 0);
 705         if (ACPI_FAILURE(status)) {
 706                 return_ACPI_STATUS(status);
 707         }
 708
 709         status = acpi_ex_resolve_to_value(&walk_state->operands[0], walk_state);
 710         if (ACPI_FAILURE(status)) {
 711                 return_ACPI_STATUS(status);
 712         }
 713
 714         ACPI_DUMP_OPERANDS(ACPI_WALK_OPERANDS,
 715                            acpi_ps_get_opcode_name(op->common.aml_opcode), 1);
 716         /*
 717          * Get the bank_value operand and save it
 718          * (at Top of stack)
 719          */
 720         operand_desc = walk_state->operands[0];
 721
 722         /* Arg points to the start Bank Field */
 723
 724         arg = acpi_ps_get_arg(op, 4);
 725         while (arg) {
 726
 727                 /* Ignore OFFSET and ACCESSAS terms here */
 728
 729                 if (arg->common.aml_opcode == AML_INT_NAMEDFIELD_OP) {
 730                         node = arg->common.node;
 731
 732                         obj_desc = acpi_ns_get_attached_object(node);
 733                         if (!obj_desc) {
 734                                 return_ACPI_STATUS(AE_NOT_EXIST);
 735                         }
 736
 737                         obj_desc->bank_field.value =
 738                             (u32) operand_desc->integer.value;
 739                 }
 740
 741                 /* Move to next field in the list */
 742
 743                 arg = arg->common.next;
 744         }
 745
 746         acpi_ut_remove_reference(operand_desc);
 747         return_ACPI_STATUS(status);
 748 }