LXR linux/drivers/acpi/acpica/dsopcode.c

   1/******************************************************************************
   2 *
   3 * Module Name: dsopcode - Dispatcher support for regions and fields
   4 *
   5 *****************************************************************************/
   6
   7/*
   8 * Copyright (C) 2000 - 2015, Intel Corp.
   9 * All rights reserved.
  10 *
  11 * Redistribution and use in source and binary forms, with or without
  12 * modification, are permitted provided that the following conditions
  13 * are met:
  14 * 1. Redistributions of source code must retain the above copyright
  15 *    notice, this list of conditions, and the following disclaimer,
  16 *    without modification.
  17 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  18 *    substantially similar to the "NO WARRANTY" disclaimer below
  19 *    ("Disclaimer") and any redistribution must be conditioned upon
  20 *    including a substantially similar Disclaimer requirement for further
  21 *    binary redistribution.
  22 * 3. Neither the names of the above-listed copyright holders nor the names
  23 *    of any contributors may be used to endorse or promote products derived
  24 *    from this software without specific prior written permission.
  25 *
  26 * Alternatively, this software may be distributed under the terms of the
  27 * GNU General Public License ("GPL") version 2 as published by the Free
  28 * Software Foundation.
  29 *
  30 * NO WARRANTY
  31 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  32 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  33 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
  34 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  35 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  36 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  37 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  38 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  39 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  40 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  41 * POSSIBILITY OF SUCH DAMAGES.
  42 */
  43
  44#include <acpi/acpi.h>
  45#include "accommon.h"
  46#include "acparser.h"
  47#include "amlcode.h"
  48#include "acdispat.h"
  49#include "acinterp.h"
  50#include "acnamesp.h"
  51#include "acevents.h"
  52#include "actables.h"
  53
  54#define _COMPONENT          ACPI_DISPATCHER
  55ACPI_MODULE_NAME("dsopcode")
  56
  57/* Local prototypes */
  58static acpi_status
  59acpi_ds_init_buffer_field(u16 aml_opcode,
  60                          union acpi_operand_object *obj_desc,
  61                          union acpi_operand_object *buffer_desc,
  62                          union acpi_operand_object *offset_desc,
  63                          union acpi_operand_object *length_desc,
  64                          union acpi_operand_object *result_desc);
  65
  66/*******************************************************************************
  67 *
  68 * FUNCTION:    acpi_ds_initialize_region
  69 *
  70 * PARAMETERS:  obj_handle      - Region namespace node
  71 *
  72 * RETURN:      Status
  73 *
  74 * DESCRIPTION: Front end to ev_initialize_region
  75 *
  76 ******************************************************************************/
  77
  78acpi_status acpi_ds_initialize_region(acpi_handle obj_handle)
  79{
  80        union acpi_operand_object *obj_desc;
  81        acpi_status status;
  82
  83        obj_desc = acpi_ns_get_attached_object(obj_handle);
  84
  85        /* Namespace is NOT locked */
  86
  87        status = acpi_ev_initialize_region(obj_desc, FALSE);
  88        return (status);
  89}
  90
  91/*******************************************************************************
  92 *
  93 * FUNCTION:    acpi_ds_init_buffer_field
  94 *
  95 * PARAMETERS:  aml_opcode      - create_xxx_field
  96 *              obj_desc        - buffer_field object
  97 *              buffer_desc     - Host Buffer
  98 *              offset_desc     - Offset into buffer
  99 *              length_desc     - Length of field (CREATE_FIELD_OP only)
 100 *              result_desc     - Where to store the result
 101 *
 102 * RETURN:      Status
 103 *
 104 * DESCRIPTION: Perform actual initialization of a buffer field
 105 *
 106 ******************************************************************************/
 107
 108static acpi_status
 109acpi_ds_init_buffer_field(u16 aml_opcode,
 110                          union acpi_operand_object *obj_desc,
 111                          union acpi_operand_object *buffer_desc,
 112                          union acpi_operand_object *offset_desc,
 113                          union acpi_operand_object *length_desc,
 114                          union acpi_operand_object *result_desc)
 115{
 116        u32 offset;
 117        u32 bit_offset;
 118        u32 bit_count;
 119        u8 field_flags;
 120        acpi_status status;
 121
 122        ACPI_FUNCTION_TRACE_PTR(ds_init_buffer_field, obj_desc);
 123
 124        /* Host object must be a Buffer */
 125
 126        if (buffer_desc->common.type != ACPI_TYPE_BUFFER) {
 127                ACPI_ERROR((AE_INFO,
 128                            "Target of Create Field is not a Buffer object - %s",
 129                            acpi_ut_get_object_type_name(buffer_desc)));
 130
 131                status = AE_AML_OPERAND_TYPE;
 132                goto cleanup;
 133        }
 134
 135        /*
 136         * The last parameter to all of these opcodes (result_desc) started
 137         * out as a name_string, and should therefore now be a NS node
 138         * after resolution in acpi_ex_resolve_operands().
 139         */
 140        if (ACPI_GET_DESCRIPTOR_TYPE(result_desc) != ACPI_DESC_TYPE_NAMED) {
 141                ACPI_ERROR((AE_INFO,
 142                            "(%s) destination not a NS Node [%s]",
 143                            acpi_ps_get_opcode_name(aml_opcode),
 144                            acpi_ut_get_descriptor_name(result_desc)));
 145
 146                status = AE_AML_OPERAND_TYPE;
 147                goto cleanup;
 148        }
 149
 150        offset = (u32) offset_desc->integer.value;
 151
 152        /*
 153         * Setup the Bit offsets and counts, according to the opcode
 154         */
 155        switch (aml_opcode) {
 156        case AML_CREATE_FIELD_OP:
 157
 158                /* Offset is in bits, count is in bits */
 159
 160                field_flags = AML_FIELD_ACCESS_BYTE;
 161                bit_offset = offset;
 162                bit_count = (u32) length_desc->integer.value;
 163
 164                /* Must have a valid (>0) bit count */
 165
 166                if (bit_count == 0) {
 167                        ACPI_ERROR((AE_INFO,
 168                                    "Attempt to CreateField of length zero"));
 169                        status = AE_AML_OPERAND_VALUE;
 170                        goto cleanup;
 171                }
 172                break;
 173
 174        case AML_CREATE_BIT_FIELD_OP:
 175
 176                /* Offset is in bits, Field is one bit */
 177
 178                bit_offset = offset;
 179                bit_count = 1;
 180                field_flags = AML_FIELD_ACCESS_BYTE;
 181                break;
 182
 183        case AML_CREATE_BYTE_FIELD_OP:
 184
 185                /* Offset is in bytes, field is one byte */
 186
 187                bit_offset = 8 * offset;
 188                bit_count = 8;
 189                field_flags = AML_FIELD_ACCESS_BYTE;
 190                break;
 191
 192        case AML_CREATE_WORD_FIELD_OP:
 193
 194                /* Offset is in bytes, field is one word */
 195
 196                bit_offset = 8 * offset;
 197                bit_count = 16;
 198                field_flags = AML_FIELD_ACCESS_WORD;
 199                break;
 200
 201        case AML_CREATE_DWORD_FIELD_OP:
 202
 203                /* Offset is in bytes, field is one dword */
 204
 205                bit_offset = 8 * offset;
 206                bit_count = 32;
 207                field_flags = AML_FIELD_ACCESS_DWORD;
 208                break;
 209
 210        case AML_CREATE_QWORD_FIELD_OP:
 211
 212                /* Offset is in bytes, field is one qword */
 213
 214                bit_offset = 8 * offset;
 215                bit_count = 64;
 216                field_flags = AML_FIELD_ACCESS_QWORD;
 217                break;
 218
 219        default:
 220
 221                ACPI_ERROR((AE_INFO,
 222                            "Unknown field creation opcode 0x%02X",
 223                            aml_opcode));
 224                status = AE_AML_BAD_OPCODE;
 225                goto cleanup;
 226        }
 227
 228        /* Entire field must fit within the current length of the buffer */
 229
 230        if ((bit_offset + bit_count) > (8 * (u32) buffer_desc->buffer.length)) {
 231                ACPI_ERROR((AE_INFO,
 232                            "Field [%4.4s] at %u exceeds Buffer [%4.4s] size %u (bits)",
 233                            acpi_ut_get_node_name(result_desc),
 234                            bit_offset + bit_count,
 235                            acpi_ut_get_node_name(buffer_desc->buffer.node),
 236                            8 * (u32) buffer_desc->buffer.length));
 237                status = AE_AML_BUFFER_LIMIT;
 238                goto cleanup;
 239        }
 240
 241        /*
 242         * Initialize areas of the field object that are common to all fields
 243         * For field_flags, use LOCK_RULE = 0 (NO_LOCK),
 244         * UPDATE_RULE = 0 (UPDATE_PRESERVE)
 245         */
 246        status = acpi_ex_prep_common_field_object(obj_desc, field_flags, 0,
 247                                                  bit_offset, bit_count);
 248        if (ACPI_FAILURE(status)) {
 249                goto cleanup;
 250        }
 251
 252        obj_desc->buffer_field.buffer_obj = buffer_desc;
 253
 254        /* Reference count for buffer_desc inherits obj_desc count */
 255
 256        buffer_desc->common.reference_count = (u16)
 257            (buffer_desc->common.reference_count +
 258             obj_desc->common.reference_count);
 259
 260cleanup:
 261
 262        /* Always delete the operands */
 263
 264        acpi_ut_remove_reference(offset_desc);
 265        acpi_ut_remove_reference(buffer_desc);
 266
 267        if (aml_opcode == AML_CREATE_FIELD_OP) {
 268                acpi_ut_remove_reference(length_desc);
 269        }
 270
 271        /* On failure, delete the result descriptor */
 272
 273        if (ACPI_FAILURE(status)) {
 274                acpi_ut_remove_reference(result_desc);  /* Result descriptor */
 275        } else {
 276                /* Now the address and length are valid for this buffer_field */
 277
 278                obj_desc->buffer_field.flags |= AOPOBJ_DATA_VALID;
 279        }
 280
 281        return_ACPI_STATUS(status);
 282}
 283
 284/*******************************************************************************
 285 *
 286 * FUNCTION:    acpi_ds_eval_buffer_field_operands
 287 *
 288 * PARAMETERS:  walk_state      - Current walk
 289 *              op              - A valid buffer_field Op object
 290 *
 291 * RETURN:      Status
 292 *
 293 * DESCRIPTION: Get buffer_field Buffer and Index
 294 *              Called from acpi_ds_exec_end_op during buffer_field parse tree walk
 295 *
 296 ******************************************************************************/
 297
 298acpi_status
 299acpi_ds_eval_buffer_field_operands(struct acpi_walk_state *walk_state,
 300                                   union acpi_parse_object *op)
 301{
 302        acpi_status status;
 303        union acpi_operand_object *obj_desc;
 304        struct acpi_namespace_node *node;
 305        union acpi_parse_object *next_op;
 306
 307        ACPI_FUNCTION_TRACE_PTR(ds_eval_buffer_field_operands, op);
 308
 309        /*
 310         * This is where we evaluate the address and length fields of the
 311         * create_xxx_field declaration
 312         */
 313        node = op->common.node;
 314
 315        /* next_op points to the op that holds the Buffer */
 316
 317        next_op = op->common.value.arg;
 318
 319        /* Evaluate/create the address and length operands */
 320
 321        status = acpi_ds_create_operands(walk_state, next_op);
 322        if (ACPI_FAILURE(status)) {
 323                return_ACPI_STATUS(status);
 324        }
 325
 326        obj_desc = acpi_ns_get_attached_object(node);
 327        if (!obj_desc) {
 328                return_ACPI_STATUS(AE_NOT_EXIST);
 329        }
 330
 331        /* Resolve the operands */
 332
 333        status = acpi_ex_resolve_operands(op->common.aml_opcode,
 334                                          ACPI_WALK_OPERANDS, walk_state);
 335        if (ACPI_FAILURE(status)) {
 336                ACPI_ERROR((AE_INFO, "(%s) bad operand(s), status 0x%X",
 337                            acpi_ps_get_opcode_name(op->common.aml_opcode),
 338                            status));
 339
 340                return_ACPI_STATUS(status);
 341        }
 342
 343        /* Initialize the Buffer Field */
 344
 345        if (op->common.aml_opcode == AML_CREATE_FIELD_OP) {
 346
 347                /* NOTE: Slightly different operands for this opcode */
 348
 349                status =
 350                    acpi_ds_init_buffer_field(op->common.aml_opcode, obj_desc,
 351                                              walk_state->operands[0],
 352                                              walk_state->operands[1],
 353                                              walk_state->operands[2],
 354                                              walk_state->operands[3]);
 355        } else {
 356                /* All other, create_xxx_field opcodes */
 357
 358                status =
 359                    acpi_ds_init_buffer_field(op->common.aml_opcode, obj_desc,
 360                                              walk_state->operands[0],
 361                                              walk_state->operands[1], NULL,
 362                                              walk_state->operands[2]);
 363        }
 364
 365        return_ACPI_STATUS(status);
 366}
 367
 368/*******************************************************************************
 369 *
 370 * FUNCTION:    acpi_ds_eval_region_operands
 371 *
 372 * PARAMETERS:  walk_state      - Current walk
 373 *              op              - A valid region Op object
 374 *
 375 * RETURN:      Status
 376 *
 377 * DESCRIPTION: Get region address and length
 378 *              Called from acpi_ds_exec_end_op during op_region parse tree walk
 379 *
 380 ******************************************************************************/
 381
 382acpi_status
 383acpi_ds_eval_region_operands(struct acpi_walk_state *walk_state,
 384                             union acpi_parse_object *op)
 385{
 386        acpi_status status;
 387        union acpi_operand_object *obj_desc;
 388        union acpi_operand_object *operand_desc;
 389        struct acpi_namespace_node *node;
 390        union acpi_parse_object *next_op;
 391
 392        ACPI_FUNCTION_TRACE_PTR(ds_eval_region_operands, op);
 393
 394        /*
 395         * This is where we evaluate the address and length fields of the
 396         * op_region declaration
 397         */
 398        node = op->common.node;
 399
 400        /* next_op points to the op that holds the space_ID */
 401
 402        next_op = op->common.value.arg;
 403
 404        /* next_op points to address op */
 405
 406        next_op = next_op->common.next;
 407
 408        /* Evaluate/create the address and length operands */
 409
 410        status = acpi_ds_create_operands(walk_state, next_op);
 411        if (ACPI_FAILURE(status)) {
 412                return_ACPI_STATUS(status);
 413        }
 414
 415        /* Resolve the length and address operands to numbers */
 416
 417        status = acpi_ex_resolve_operands(op->common.aml_opcode,
 418                                          ACPI_WALK_OPERANDS, walk_state);
 419        if (ACPI_FAILURE(status)) {
 420                return_ACPI_STATUS(status);
 421        }
 422
 423        obj_desc = acpi_ns_get_attached_object(node);
 424        if (!obj_desc) {
 425                return_ACPI_STATUS(AE_NOT_EXIST);
 426        }
 427
 428        /*
 429         * Get the length operand and save it
 430         * (at Top of stack)
 431         */
 432        operand_desc = walk_state->operands[walk_state->num_operands - 1];
 433
 434        obj_desc->region.length = (u32) operand_desc->integer.value;
 435        acpi_ut_remove_reference(operand_desc);
 436
 437        /*
 438         * Get the address and save it
 439         * (at top of stack - 1)
 440         */
 441        operand_desc = walk_state->operands[walk_state->num_operands - 2];
 442
 443        obj_desc->region.address = (acpi_physical_address)
 444            operand_desc->integer.value;
 445        acpi_ut_remove_reference(operand_desc);
 446
 447        ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "RgnObj %p Addr %8.8X%8.8X Len %X\n",
 448                          obj_desc,
 449                          ACPI_FORMAT_UINT64(obj_desc->region.address),
 450                          obj_desc->region.length));
 451
 452        /* Now the address and length are valid for this opregion */
 453
 454        obj_desc->region.flags |= AOPOBJ_DATA_VALID;
 455
 456        return_ACPI_STATUS(status);
 457}
 458
 459/*******************************************************************************
 460 *
 461 * FUNCTION:    acpi_ds_eval_table_region_operands
 462 *
 463 * PARAMETERS:  walk_state      - Current walk
 464 *              op              - A valid region Op object
 465 *
 466 * RETURN:      Status
 467 *
 468 * DESCRIPTION: Get region address and length.
 469 *              Called from acpi_ds_exec_end_op during data_table_region parse
 470 *              tree walk.
 471 *
 472 ******************************************************************************/
 473
 474acpi_status
 475acpi_ds_eval_table_region_operands(struct acpi_walk_state *walk_state,
 476                                   union acpi_parse_object *op)
 477{
 478        acpi_status status;
 479        union acpi_operand_object *obj_desc;
 480        union acpi_operand_object **operand;
 481        struct acpi_namespace_node *node;
 482        union acpi_parse_object *next_op;
 483        u32 table_index;
 484        struct acpi_table_header *table;
 485
 486        ACPI_FUNCTION_TRACE_PTR(ds_eval_table_region_operands, op);
 487
 488        /*
 489         * This is where we evaluate the Signature string, oem_id string,
 490         * and oem_table_id string of the Data Table Region declaration
 491         */
 492        node = op->common.node;
 493
 494        /* next_op points to Signature string op */
 495
 496        next_op = op->common.value.arg;
 497
 498        /*
 499         * Evaluate/create the Signature string, oem_id string,
 500         * and oem_table_id string operands
 501         */
 502        status = acpi_ds_create_operands(walk_state, next_op);
 503        if (ACPI_FAILURE(status)) {
 504                return_ACPI_STATUS(status);
 505        }
 506
 507        /*
 508         * Resolve the Signature string, oem_id string,
 509         * and oem_table_id string operands
 510         */
 511        status = acpi_ex_resolve_operands(op->common.aml_opcode,
 512                                          ACPI_WALK_OPERANDS, walk_state);
 513        if (ACPI_FAILURE(status)) {
 514                return_ACPI_STATUS(status);
 515        }
 516
 517        operand = &walk_state->operands[0];
 518
 519        /* Find the ACPI table */
 520
 521        status = acpi_tb_find_table(operand[0]->string.pointer,
 522                                    operand[1]->string.pointer,
 523                                    operand[2]->string.pointer, &table_index);
 524        if (ACPI_FAILURE(status)) {
 525                return_ACPI_STATUS(status);
 526        }
 527
 528        acpi_ut_remove_reference(operand[0]);
 529        acpi_ut_remove_reference(operand[1]);
 530        acpi_ut_remove_reference(operand[2]);
 531
 532        status = acpi_get_table_by_index(table_index, &table);
 533        if (ACPI_FAILURE(status)) {
 534                return_ACPI_STATUS(status);
 535        }
 536
 537        obj_desc = acpi_ns_get_attached_object(node);
 538        if (!obj_desc) {
 539                return_ACPI_STATUS(AE_NOT_EXIST);
 540        }
 541
 542        obj_desc->region.address = ACPI_PTR_TO_PHYSADDR(table);
 543        obj_desc->region.length = table->length;
 544
 545        ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "RgnObj %p Addr %8.8X%8.8X Len %X\n",
 546                          obj_desc,
 547                          ACPI_FORMAT_UINT64(obj_desc->region.address),
 548                          obj_desc->region.length));
 549
 550        /* Now the address and length are valid for this opregion */
 551
 552        obj_desc->region.flags |= AOPOBJ_DATA_VALID;
 553
 554        return_ACPI_STATUS(status);
 555}
 556
 557/*******************************************************************************
 558 *
 559 * FUNCTION:    acpi_ds_eval_data_object_operands
 560 *
 561 * PARAMETERS:  walk_state      - Current walk
 562 *              op              - A valid data_object Op object
 563 *              obj_desc        - data_object
 564 *
 565 * RETURN:      Status
 566 *
 567 * DESCRIPTION: Get the operands and complete the following data object types:
 568 *              Buffer, Package.
 569 *
 570 ******************************************************************************/
 571
 572acpi_status
 573acpi_ds_eval_data_object_operands(struct acpi_walk_state *walk_state,
 574                                  union acpi_parse_object *op,
 575                                  union acpi_operand_object *obj_desc)
 576{
 577        acpi_status status;
 578        union acpi_operand_object *arg_desc;
 579        u32 length;
 580
 581        ACPI_FUNCTION_TRACE(ds_eval_data_object_operands);
 582
 583        /* The first operand (for all of these data objects) is the length */
 584
 585        /*
 586         * Set proper index into operand stack for acpi_ds_obj_stack_push
 587         * invoked inside acpi_ds_create_operand.
 588         */
 589        walk_state->operand_index = walk_state->num_operands;
 590
 591        status = acpi_ds_create_operand(walk_state, op->common.value.arg, 1);
 592        if (ACPI_FAILURE(status)) {
 593                return_ACPI_STATUS(status);
 594        }
 595
 596        status = acpi_ex_resolve_operands(walk_state->opcode,
 597                                          &(walk_state->
 598                                            operands[walk_state->num_operands -
 599                                                     1]), walk_state);
 600        if (ACPI_FAILURE(status)) {
 601                return_ACPI_STATUS(status);
 602        }
 603
 604        /* Extract length operand */
 605
 606        arg_desc = walk_state->operands[walk_state->num_operands - 1];
 607        length = (u32) arg_desc->integer.value;
 608
 609        /* Cleanup for length operand */
 610
 611        status = acpi_ds_obj_stack_pop(1, walk_state);
 612        if (ACPI_FAILURE(status)) {
 613                return_ACPI_STATUS(status);
 614        }
 615
 616        acpi_ut_remove_reference(arg_desc);
 617
 618        /*
 619         * Create the actual data object
 620         */
 621        switch (op->common.aml_opcode) {
 622        case AML_BUFFER_OP:
 623
 624                status =
 625                    acpi_ds_build_internal_buffer_obj(walk_state, op, length,
 626                                                      &obj_desc);
 627                break;
 628
 629        case AML_PACKAGE_OP:
 630        case AML_VAR_PACKAGE_OP:
 631
 632                status =
 633                    acpi_ds_build_internal_package_obj(walk_state, op, length,
 634                                                       &obj_desc);
 635                break;
 636
 637        default:
 638
 639                return_ACPI_STATUS(AE_AML_BAD_OPCODE);
 640        }
 641
 642        if (ACPI_SUCCESS(status)) {
 643                /*
 644                 * Return the object in the walk_state, unless the parent is a package -
 645                 * in this case, the return object will be stored in the parse tree
 646                 * for the package.
 647                 */
 648                if ((!op->common.parent) ||
 649                    ((op->common.parent->common.aml_opcode != AML_PACKAGE_OP) &&
 650                     (op->common.parent->common.aml_opcode !=
 651                      AML_VAR_PACKAGE_OP)
 652                     && (op->common.parent->common.aml_opcode !=
 653                         AML_NAME_OP))) {
 654                        walk_state->result_obj = obj_desc;
 655                }
 656        }
 657
 658        return_ACPI_STATUS(status);
 659}
 660
 661/*******************************************************************************
 662 *
 663 * FUNCTION:    acpi_ds_eval_bank_field_operands
 664 *
 665 * PARAMETERS:  walk_state      - Current walk
 666 *              op              - A valid bank_field Op object
 667 *
 668 * RETURN:      Status
 669 *
 670 * DESCRIPTION: Get bank_field bank_value
 671 *              Called from acpi_ds_exec_end_op during bank_field parse tree walk
 672 *
 673 ******************************************************************************/
 674
 675acpi_status
 676acpi_ds_eval_bank_field_operands(struct acpi_walk_state *walk_state,
 677                                 union acpi_parse_object *op)
 678{
 679        acpi_status status;
 680        union acpi_operand_object *obj_desc;
 681        union acpi_operand_object *operand_desc;
 682        struct acpi_namespace_node *node;
 683        union acpi_parse_object *next_op;
 684        union acpi_parse_object *arg;
 685
 686        ACPI_FUNCTION_TRACE_PTR(ds_eval_bank_field_operands, op);
 687
 688        /*
 689         * This is where we evaluate the bank_value field of the
 690         * bank_field declaration
 691         */
 692
 693        /* next_op points to the op that holds the Region */
 694
 695        next_op = op->common.value.arg;
 696
 697        /* next_op points to the op that holds the Bank Register */
 698
 699        next_op = next_op->common.next;
 700
 701        /* next_op points to the op that holds the Bank Value */
 702
 703        next_op = next_op->common.next;
 704
 705        /*
 706         * Set proper index into operand stack for acpi_ds_obj_stack_push
 707         * invoked inside acpi_ds_create_operand.
 708         *
 709         * We use walk_state->Operands[0] to store the evaluated bank_value
 710         */
 711        walk_state->operand_index = 0;
 712
 713        status = acpi_ds_create_operand(walk_state, next_op, 0);
 714        if (ACPI_FAILURE(status)) {
 715                return_ACPI_STATUS(status);
 716        }
 717
 718        status = acpi_ex_resolve_to_value(&walk_state->operands[0], walk_state);
 719        if (ACPI_FAILURE(status)) {
 720                return_ACPI_STATUS(status);
 721        }
 722
 723        ACPI_DUMP_OPERANDS(ACPI_WALK_OPERANDS,
 724                           acpi_ps_get_opcode_name(op->common.aml_opcode), 1);
 725        /*
 726         * Get the bank_value operand and save it
 727         * (at Top of stack)
 728         */
 729        operand_desc = walk_state->operands[0];
 730
 731        /* Arg points to the start Bank Field */
 732
 733        arg = acpi_ps_get_arg(op, 4);
 734        while (arg) {
 735
 736                /* Ignore OFFSET and ACCESSAS terms here */
 737
 738                if (arg->common.aml_opcode == AML_INT_NAMEDFIELD_OP) {
 739                        node = arg->common.node;
 740
 741                        obj_desc = acpi_ns_get_attached_object(node);
 742                        if (!obj_desc) {
 743                                return_ACPI_STATUS(AE_NOT_EXIST);
 744                        }
 745
 746                        obj_desc->bank_field.value =
 747                            (u32) operand_desc->integer.value;
 748                }
 749
 750                /* Move to next field in the list */
 751
 752                arg = arg->common.next;
 753        }
 754
 755        acpi_ut_remove_reference(operand_desc);
 756        return_ACPI_STATUS(status);
 757}
 758