linux/drivers/acpi/acpica/dsopcode.c
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   1/******************************************************************************
   2 *
   3 * Module Name: dsopcode - Dispatcher Op Region support and handling of
   4 *                         "control" opcodes
   5 *
   6 *****************************************************************************/
   7
   8/*
   9 * Copyright (C) 2000 - 2011, Intel Corp.
  10 * All rights reserved.
  11 *
  12 * Redistribution and use in source and binary forms, with or without
  13 * modification, are permitted provided that the following conditions
  14 * are met:
  15 * 1. Redistributions of source code must retain the above copyright
  16 *    notice, this list of conditions, and the following disclaimer,
  17 *    without modification.
  18 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  19 *    substantially similar to the "NO WARRANTY" disclaimer below
  20 *    ("Disclaimer") and any redistribution must be conditioned upon
  21 *    including a substantially similar Disclaimer requirement for further
  22 *    binary redistribution.
  23 * 3. Neither the names of the above-listed copyright holders nor the names
  24 *    of any contributors may be used to endorse or promote products derived
  25 *    from this software without specific prior written permission.
  26 *
  27 * Alternatively, this software may be distributed under the terms of the
  28 * GNU General Public License ("GPL") version 2 as published by the Free
  29 * Software Foundation.
  30 *
  31 * NO WARRANTY
  32 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  33 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  34 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
  35 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  36 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  37 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  38 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  39 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  40 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  41 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  42 * POSSIBILITY OF SUCH DAMAGES.
  43 */
  44
  45#include <acpi/acpi.h>
  46#include "accommon.h"
  47#include "acparser.h"
  48#include "amlcode.h"
  49#include "acdispat.h"
  50#include "acinterp.h"
  51#include "acnamesp.h"
  52#include "acevents.h"
  53#include "actables.h"
  54
  55#define _COMPONENT          ACPI_DISPATCHER
  56ACPI_MODULE_NAME("dsopcode")
  57
  58/* Local prototypes */
  59static acpi_status
  60acpi_ds_execute_arguments(struct acpi_namespace_node *node,
  61                          struct acpi_namespace_node *scope_node,
  62                          u32 aml_length, u8 * aml_start);
  63
  64static acpi_status
  65acpi_ds_init_buffer_field(u16 aml_opcode,
  66                          union acpi_operand_object *obj_desc,
  67                          union acpi_operand_object *buffer_desc,
  68                          union acpi_operand_object *offset_desc,
  69                          union acpi_operand_object *length_desc,
  70                          union acpi_operand_object *result_desc);
  71
  72/*******************************************************************************
  73 *
  74 * FUNCTION:    acpi_ds_execute_arguments
  75 *
  76 * PARAMETERS:  Node                - Object NS node
  77 *              scope_node          - Parent NS node
  78 *              aml_length          - Length of executable AML
  79 *              aml_start           - Pointer to the AML
  80 *
  81 * RETURN:      Status.
  82 *
  83 * DESCRIPTION: Late (deferred) execution of region or field arguments
  84 *
  85 ******************************************************************************/
  86
  87static acpi_status
  88acpi_ds_execute_arguments(struct acpi_namespace_node *node,
  89                          struct acpi_namespace_node *scope_node,
  90                          u32 aml_length, u8 * aml_start)
  91{
  92        acpi_status status;
  93        union acpi_parse_object *op;
  94        struct acpi_walk_state *walk_state;
  95
  96        ACPI_FUNCTION_TRACE(ds_execute_arguments);
  97
  98        /*
  99         * Allocate a new parser op to be the root of the parsed tree
 100         */
 101        op = acpi_ps_alloc_op(AML_INT_EVAL_SUBTREE_OP);
 102        if (!op) {
 103                return_ACPI_STATUS(AE_NO_MEMORY);
 104        }
 105
 106        /* Save the Node for use in acpi_ps_parse_aml */
 107
 108        op->common.node = scope_node;
 109
 110        /* Create and initialize a new parser state */
 111
 112        walk_state = acpi_ds_create_walk_state(0, NULL, NULL, NULL);
 113        if (!walk_state) {
 114                status = AE_NO_MEMORY;
 115                goto cleanup;
 116        }
 117
 118        status = acpi_ds_init_aml_walk(walk_state, op, NULL, aml_start,
 119                                       aml_length, NULL, ACPI_IMODE_LOAD_PASS1);
 120        if (ACPI_FAILURE(status)) {
 121                acpi_ds_delete_walk_state(walk_state);
 122                goto cleanup;
 123        }
 124
 125        /* Mark this parse as a deferred opcode */
 126
 127        walk_state->parse_flags = ACPI_PARSE_DEFERRED_OP;
 128        walk_state->deferred_node = node;
 129
 130        /* Pass1: Parse the entire declaration */
 131
 132        status = acpi_ps_parse_aml(walk_state);
 133        if (ACPI_FAILURE(status)) {
 134                goto cleanup;
 135        }
 136
 137        /* Get and init the Op created above */
 138
 139        op->common.node = node;
 140        acpi_ps_delete_parse_tree(op);
 141
 142        /* Evaluate the deferred arguments */
 143
 144        op = acpi_ps_alloc_op(AML_INT_EVAL_SUBTREE_OP);
 145        if (!op) {
 146                return_ACPI_STATUS(AE_NO_MEMORY);
 147        }
 148
 149        op->common.node = scope_node;
 150
 151        /* Create and initialize a new parser state */
 152
 153        walk_state = acpi_ds_create_walk_state(0, NULL, NULL, NULL);
 154        if (!walk_state) {
 155                status = AE_NO_MEMORY;
 156                goto cleanup;
 157        }
 158
 159        /* Execute the opcode and arguments */
 160
 161        status = acpi_ds_init_aml_walk(walk_state, op, NULL, aml_start,
 162                                       aml_length, NULL, ACPI_IMODE_EXECUTE);
 163        if (ACPI_FAILURE(status)) {
 164                acpi_ds_delete_walk_state(walk_state);
 165                goto cleanup;
 166        }
 167
 168        /* Mark this execution as a deferred opcode */
 169
 170        walk_state->deferred_node = node;
 171        status = acpi_ps_parse_aml(walk_state);
 172
 173      cleanup:
 174        acpi_ps_delete_parse_tree(op);
 175        return_ACPI_STATUS(status);
 176}
 177
 178/*******************************************************************************
 179 *
 180 * FUNCTION:    acpi_ds_get_buffer_field_arguments
 181 *
 182 * PARAMETERS:  obj_desc        - A valid buffer_field object
 183 *
 184 * RETURN:      Status.
 185 *
 186 * DESCRIPTION: Get buffer_field Buffer and Index. This implements the late
 187 *              evaluation of these field attributes.
 188 *
 189 ******************************************************************************/
 190
 191acpi_status
 192acpi_ds_get_buffer_field_arguments(union acpi_operand_object *obj_desc)
 193{
 194        union acpi_operand_object *extra_desc;
 195        struct acpi_namespace_node *node;
 196        acpi_status status;
 197
 198        ACPI_FUNCTION_TRACE_PTR(ds_get_buffer_field_arguments, obj_desc);
 199
 200        if (obj_desc->common.flags & AOPOBJ_DATA_VALID) {
 201                return_ACPI_STATUS(AE_OK);
 202        }
 203
 204        /* Get the AML pointer (method object) and buffer_field node */
 205
 206        extra_desc = acpi_ns_get_secondary_object(obj_desc);
 207        node = obj_desc->buffer_field.node;
 208
 209        ACPI_DEBUG_EXEC(acpi_ut_display_init_pathname
 210                        (ACPI_TYPE_BUFFER_FIELD, node, NULL));
 211        ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "[%4.4s] BufferField Arg Init\n",
 212                          acpi_ut_get_node_name(node)));
 213
 214        /* Execute the AML code for the term_arg arguments */
 215
 216        status = acpi_ds_execute_arguments(node, node->parent,
 217                                           extra_desc->extra.aml_length,
 218                                           extra_desc->extra.aml_start);
 219        return_ACPI_STATUS(status);
 220}
 221
 222/*******************************************************************************
 223 *
 224 * FUNCTION:    acpi_ds_get_bank_field_arguments
 225 *
 226 * PARAMETERS:  obj_desc        - A valid bank_field object
 227 *
 228 * RETURN:      Status.
 229 *
 230 * DESCRIPTION: Get bank_field bank_value. This implements the late
 231 *              evaluation of these field attributes.
 232 *
 233 ******************************************************************************/
 234
 235acpi_status
 236acpi_ds_get_bank_field_arguments(union acpi_operand_object *obj_desc)
 237{
 238        union acpi_operand_object *extra_desc;
 239        struct acpi_namespace_node *node;
 240        acpi_status status;
 241
 242        ACPI_FUNCTION_TRACE_PTR(ds_get_bank_field_arguments, obj_desc);
 243
 244        if (obj_desc->common.flags & AOPOBJ_DATA_VALID) {
 245                return_ACPI_STATUS(AE_OK);
 246        }
 247
 248        /* Get the AML pointer (method object) and bank_field node */
 249
 250        extra_desc = acpi_ns_get_secondary_object(obj_desc);
 251        node = obj_desc->bank_field.node;
 252
 253        ACPI_DEBUG_EXEC(acpi_ut_display_init_pathname
 254                        (ACPI_TYPE_LOCAL_BANK_FIELD, node, NULL));
 255        ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "[%4.4s] BankField Arg Init\n",
 256                          acpi_ut_get_node_name(node)));
 257
 258        /* Execute the AML code for the term_arg arguments */
 259
 260        status = acpi_ds_execute_arguments(node, node->parent,
 261                                           extra_desc->extra.aml_length,
 262                                           extra_desc->extra.aml_start);
 263        return_ACPI_STATUS(status);
 264}
 265
 266/*******************************************************************************
 267 *
 268 * FUNCTION:    acpi_ds_get_buffer_arguments
 269 *
 270 * PARAMETERS:  obj_desc        - A valid Buffer object
 271 *
 272 * RETURN:      Status.
 273 *
 274 * DESCRIPTION: Get Buffer length and initializer byte list.  This implements
 275 *              the late evaluation of these attributes.
 276 *
 277 ******************************************************************************/
 278
 279acpi_status acpi_ds_get_buffer_arguments(union acpi_operand_object *obj_desc)
 280{
 281        struct acpi_namespace_node *node;
 282        acpi_status status;
 283
 284        ACPI_FUNCTION_TRACE_PTR(ds_get_buffer_arguments, obj_desc);
 285
 286        if (obj_desc->common.flags & AOPOBJ_DATA_VALID) {
 287                return_ACPI_STATUS(AE_OK);
 288        }
 289
 290        /* Get the Buffer node */
 291
 292        node = obj_desc->buffer.node;
 293        if (!node) {
 294                ACPI_ERROR((AE_INFO,
 295                            "No pointer back to namespace node in buffer object %p",
 296                            obj_desc));
 297                return_ACPI_STATUS(AE_AML_INTERNAL);
 298        }
 299
 300        ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Buffer Arg Init\n"));
 301
 302        /* Execute the AML code for the term_arg arguments */
 303
 304        status = acpi_ds_execute_arguments(node, node,
 305                                           obj_desc->buffer.aml_length,
 306                                           obj_desc->buffer.aml_start);
 307        return_ACPI_STATUS(status);
 308}
 309
 310/*******************************************************************************
 311 *
 312 * FUNCTION:    acpi_ds_get_package_arguments
 313 *
 314 * PARAMETERS:  obj_desc        - A valid Package object
 315 *
 316 * RETURN:      Status.
 317 *
 318 * DESCRIPTION: Get Package length and initializer byte list.  This implements
 319 *              the late evaluation of these attributes.
 320 *
 321 ******************************************************************************/
 322
 323acpi_status acpi_ds_get_package_arguments(union acpi_operand_object *obj_desc)
 324{
 325        struct acpi_namespace_node *node;
 326        acpi_status status;
 327
 328        ACPI_FUNCTION_TRACE_PTR(ds_get_package_arguments, obj_desc);
 329
 330        if (obj_desc->common.flags & AOPOBJ_DATA_VALID) {
 331                return_ACPI_STATUS(AE_OK);
 332        }
 333
 334        /* Get the Package node */
 335
 336        node = obj_desc->package.node;
 337        if (!node) {
 338                ACPI_ERROR((AE_INFO,
 339                            "No pointer back to namespace node in package %p",
 340                            obj_desc));
 341                return_ACPI_STATUS(AE_AML_INTERNAL);
 342        }
 343
 344        ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Package Arg Init\n"));
 345
 346        /* Execute the AML code for the term_arg arguments */
 347
 348        status = acpi_ds_execute_arguments(node, node,
 349                                           obj_desc->package.aml_length,
 350                                           obj_desc->package.aml_start);
 351        return_ACPI_STATUS(status);
 352}
 353
 354/*****************************************************************************
 355 *
 356 * FUNCTION:    acpi_ds_get_region_arguments
 357 *
 358 * PARAMETERS:  obj_desc        - A valid region object
 359 *
 360 * RETURN:      Status.
 361 *
 362 * DESCRIPTION: Get region address and length.  This implements the late
 363 *              evaluation of these region attributes.
 364 *
 365 ****************************************************************************/
 366
 367acpi_status acpi_ds_get_region_arguments(union acpi_operand_object *obj_desc)
 368{
 369        struct acpi_namespace_node *node;
 370        acpi_status status;
 371        union acpi_operand_object *extra_desc;
 372
 373        ACPI_FUNCTION_TRACE_PTR(ds_get_region_arguments, obj_desc);
 374
 375        if (obj_desc->region.flags & AOPOBJ_DATA_VALID) {
 376                return_ACPI_STATUS(AE_OK);
 377        }
 378
 379        extra_desc = acpi_ns_get_secondary_object(obj_desc);
 380        if (!extra_desc) {
 381                return_ACPI_STATUS(AE_NOT_EXIST);
 382        }
 383
 384        /* Get the Region node */
 385
 386        node = obj_desc->region.node;
 387
 388        ACPI_DEBUG_EXEC(acpi_ut_display_init_pathname
 389                        (ACPI_TYPE_REGION, node, NULL));
 390
 391        ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "[%4.4s] OpRegion Arg Init at AML %p\n",
 392                          acpi_ut_get_node_name(node),
 393                          extra_desc->extra.aml_start));
 394
 395        /* Execute the argument AML */
 396
 397        status = acpi_ds_execute_arguments(node, node->parent,
 398                                           extra_desc->extra.aml_length,
 399                                           extra_desc->extra.aml_start);
 400        if (ACPI_FAILURE(status)) {
 401                return_ACPI_STATUS(status);
 402        }
 403
 404        /* Validate the region address/length via the host OS */
 405
 406        status = acpi_os_validate_address(obj_desc->region.space_id,
 407                                          obj_desc->region.address,
 408                                          (acpi_size) obj_desc->region.length,
 409                                          acpi_ut_get_node_name(node));
 410
 411        if (ACPI_FAILURE(status)) {
 412                /*
 413                 * Invalid address/length. We will emit an error message and mark
 414                 * the region as invalid, so that it will cause an additional error if
 415                 * it is ever used. Then return AE_OK.
 416                 */
 417                ACPI_EXCEPTION((AE_INFO, status,
 418                                "During address validation of OpRegion [%4.4s]",
 419                                node->name.ascii));
 420                obj_desc->common.flags |= AOPOBJ_INVALID;
 421                status = AE_OK;
 422        }
 423
 424        return_ACPI_STATUS(status);
 425}
 426
 427/*******************************************************************************
 428 *
 429 * FUNCTION:    acpi_ds_initialize_region
 430 *
 431 * PARAMETERS:  obj_handle      - Region namespace node
 432 *
 433 * RETURN:      Status
 434 *
 435 * DESCRIPTION: Front end to ev_initialize_region
 436 *
 437 ******************************************************************************/
 438
 439acpi_status acpi_ds_initialize_region(acpi_handle obj_handle)
 440{
 441        union acpi_operand_object *obj_desc;
 442        acpi_status status;
 443
 444        obj_desc = acpi_ns_get_attached_object(obj_handle);
 445
 446        /* Namespace is NOT locked */
 447
 448        status = acpi_ev_initialize_region(obj_desc, FALSE);
 449        return (status);
 450}
 451
 452/*******************************************************************************
 453 *
 454 * FUNCTION:    acpi_ds_init_buffer_field
 455 *
 456 * PARAMETERS:  aml_opcode      - create_xxx_field
 457 *              obj_desc        - buffer_field object
 458 *              buffer_desc     - Host Buffer
 459 *              offset_desc     - Offset into buffer
 460 *              length_desc     - Length of field (CREATE_FIELD_OP only)
 461 *              result_desc     - Where to store the result
 462 *
 463 * RETURN:      Status
 464 *
 465 * DESCRIPTION: Perform actual initialization of a buffer field
 466 *
 467 ******************************************************************************/
 468
 469static acpi_status
 470acpi_ds_init_buffer_field(u16 aml_opcode,
 471                          union acpi_operand_object *obj_desc,
 472                          union acpi_operand_object *buffer_desc,
 473                          union acpi_operand_object *offset_desc,
 474                          union acpi_operand_object *length_desc,
 475                          union acpi_operand_object *result_desc)
 476{
 477        u32 offset;
 478        u32 bit_offset;
 479        u32 bit_count;
 480        u8 field_flags;
 481        acpi_status status;
 482
 483        ACPI_FUNCTION_TRACE_PTR(ds_init_buffer_field, obj_desc);
 484
 485        /* Host object must be a Buffer */
 486
 487        if (buffer_desc->common.type != ACPI_TYPE_BUFFER) {
 488                ACPI_ERROR((AE_INFO,
 489                            "Target of Create Field is not a Buffer object - %s",
 490                            acpi_ut_get_object_type_name(buffer_desc)));
 491
 492                status = AE_AML_OPERAND_TYPE;
 493                goto cleanup;
 494        }
 495
 496        /*
 497         * The last parameter to all of these opcodes (result_desc) started
 498         * out as a name_string, and should therefore now be a NS node
 499         * after resolution in acpi_ex_resolve_operands().
 500         */
 501        if (ACPI_GET_DESCRIPTOR_TYPE(result_desc) != ACPI_DESC_TYPE_NAMED) {
 502                ACPI_ERROR((AE_INFO,
 503                            "(%s) destination not a NS Node [%s]",
 504                            acpi_ps_get_opcode_name(aml_opcode),
 505                            acpi_ut_get_descriptor_name(result_desc)));
 506
 507                status = AE_AML_OPERAND_TYPE;
 508                goto cleanup;
 509        }
 510
 511        offset = (u32) offset_desc->integer.value;
 512
 513        /*
 514         * Setup the Bit offsets and counts, according to the opcode
 515         */
 516        switch (aml_opcode) {
 517        case AML_CREATE_FIELD_OP:
 518
 519                /* Offset is in bits, count is in bits */
 520
 521                field_flags = AML_FIELD_ACCESS_BYTE;
 522                bit_offset = offset;
 523                bit_count = (u32) length_desc->integer.value;
 524
 525                /* Must have a valid (>0) bit count */
 526
 527                if (bit_count == 0) {
 528                        ACPI_ERROR((AE_INFO,
 529                                    "Attempt to CreateField of length zero"));
 530                        status = AE_AML_OPERAND_VALUE;
 531                        goto cleanup;
 532                }
 533                break;
 534
 535        case AML_CREATE_BIT_FIELD_OP:
 536
 537                /* Offset is in bits, Field is one bit */
 538
 539                bit_offset = offset;
 540                bit_count = 1;
 541                field_flags = AML_FIELD_ACCESS_BYTE;
 542                break;
 543
 544        case AML_CREATE_BYTE_FIELD_OP:
 545
 546                /* Offset is in bytes, field is one byte */
 547
 548                bit_offset = 8 * offset;
 549                bit_count = 8;
 550                field_flags = AML_FIELD_ACCESS_BYTE;
 551                break;
 552
 553        case AML_CREATE_WORD_FIELD_OP:
 554
 555                /* Offset is in bytes, field is one word */
 556
 557                bit_offset = 8 * offset;
 558                bit_count = 16;
 559                field_flags = AML_FIELD_ACCESS_WORD;
 560                break;
 561
 562        case AML_CREATE_DWORD_FIELD_OP:
 563
 564                /* Offset is in bytes, field is one dword */
 565
 566                bit_offset = 8 * offset;
 567                bit_count = 32;
 568                field_flags = AML_FIELD_ACCESS_DWORD;
 569                break;
 570
 571        case AML_CREATE_QWORD_FIELD_OP:
 572
 573                /* Offset is in bytes, field is one qword */
 574
 575                bit_offset = 8 * offset;
 576                bit_count = 64;
 577                field_flags = AML_FIELD_ACCESS_QWORD;
 578                break;
 579
 580        default:
 581
 582                ACPI_ERROR((AE_INFO,
 583                            "Unknown field creation opcode 0x%02X",
 584                            aml_opcode));
 585                status = AE_AML_BAD_OPCODE;
 586                goto cleanup;
 587        }
 588
 589        /* Entire field must fit within the current length of the buffer */
 590
 591        if ((bit_offset + bit_count) > (8 * (u32) buffer_desc->buffer.length)) {
 592                ACPI_ERROR((AE_INFO,
 593                            "Field [%4.4s] at %u exceeds Buffer [%4.4s] size %u (bits)",
 594                            acpi_ut_get_node_name(result_desc),
 595                            bit_offset + bit_count,
 596                            acpi_ut_get_node_name(buffer_desc->buffer.node),
 597                            8 * (u32) buffer_desc->buffer.length));
 598                status = AE_AML_BUFFER_LIMIT;
 599                goto cleanup;
 600        }
 601
 602        /*
 603         * Initialize areas of the field object that are common to all fields
 604         * For field_flags, use LOCK_RULE = 0 (NO_LOCK),
 605         * UPDATE_RULE = 0 (UPDATE_PRESERVE)
 606         */
 607        status = acpi_ex_prep_common_field_object(obj_desc, field_flags, 0,
 608                                                  bit_offset, bit_count);
 609        if (ACPI_FAILURE(status)) {
 610                goto cleanup;
 611        }
 612
 613        obj_desc->buffer_field.buffer_obj = buffer_desc;
 614
 615        /* Reference count for buffer_desc inherits obj_desc count */
 616
 617        buffer_desc->common.reference_count = (u16)
 618            (buffer_desc->common.reference_count +
 619             obj_desc->common.reference_count);
 620
 621      cleanup:
 622
 623        /* Always delete the operands */
 624
 625        acpi_ut_remove_reference(offset_desc);
 626        acpi_ut_remove_reference(buffer_desc);
 627
 628        if (aml_opcode == AML_CREATE_FIELD_OP) {
 629                acpi_ut_remove_reference(length_desc);
 630        }
 631
 632        /* On failure, delete the result descriptor */
 633
 634        if (ACPI_FAILURE(status)) {
 635                acpi_ut_remove_reference(result_desc);  /* Result descriptor */
 636        } else {
 637                /* Now the address and length are valid for this buffer_field */
 638
 639                obj_desc->buffer_field.flags |= AOPOBJ_DATA_VALID;
 640        }
 641
 642        return_ACPI_STATUS(status);
 643}
 644
 645/*******************************************************************************
 646 *
 647 * FUNCTION:    acpi_ds_eval_buffer_field_operands
 648 *
 649 * PARAMETERS:  walk_state      - Current walk
 650 *              Op              - A valid buffer_field Op object
 651 *
 652 * RETURN:      Status
 653 *
 654 * DESCRIPTION: Get buffer_field Buffer and Index
 655 *              Called from acpi_ds_exec_end_op during buffer_field parse tree walk
 656 *
 657 ******************************************************************************/
 658
 659acpi_status
 660acpi_ds_eval_buffer_field_operands(struct acpi_walk_state *walk_state,
 661                                   union acpi_parse_object *op)
 662{
 663        acpi_status status;
 664        union acpi_operand_object *obj_desc;
 665        struct acpi_namespace_node *node;
 666        union acpi_parse_object *next_op;
 667
 668        ACPI_FUNCTION_TRACE_PTR(ds_eval_buffer_field_operands, op);
 669
 670        /*
 671         * This is where we evaluate the address and length fields of the
 672         * create_xxx_field declaration
 673         */
 674        node = op->common.node;
 675
 676        /* next_op points to the op that holds the Buffer */
 677
 678        next_op = op->common.value.arg;
 679
 680        /* Evaluate/create the address and length operands */
 681
 682        status = acpi_ds_create_operands(walk_state, next_op);
 683        if (ACPI_FAILURE(status)) {
 684                return_ACPI_STATUS(status);
 685        }
 686
 687        obj_desc = acpi_ns_get_attached_object(node);
 688        if (!obj_desc) {
 689                return_ACPI_STATUS(AE_NOT_EXIST);
 690        }
 691
 692        /* Resolve the operands */
 693
 694        status = acpi_ex_resolve_operands(op->common.aml_opcode,
 695                                          ACPI_WALK_OPERANDS, walk_state);
 696        if (ACPI_FAILURE(status)) {
 697                ACPI_ERROR((AE_INFO, "(%s) bad operand(s), status 0x%X",
 698                            acpi_ps_get_opcode_name(op->common.aml_opcode),
 699                            status));
 700
 701                return_ACPI_STATUS(status);
 702        }
 703
 704        /* Initialize the Buffer Field */
 705
 706        if (op->common.aml_opcode == AML_CREATE_FIELD_OP) {
 707
 708                /* NOTE: Slightly different operands for this opcode */
 709
 710                status =
 711                    acpi_ds_init_buffer_field(op->common.aml_opcode, obj_desc,
 712                                              walk_state->operands[0],
 713                                              walk_state->operands[1],
 714                                              walk_state->operands[2],
 715                                              walk_state->operands[3]);
 716        } else {
 717                /* All other, create_xxx_field opcodes */
 718
 719                status =
 720                    acpi_ds_init_buffer_field(op->common.aml_opcode, obj_desc,
 721                                              walk_state->operands[0],
 722                                              walk_state->operands[1], NULL,
 723                                              walk_state->operands[2]);
 724        }
 725
 726        return_ACPI_STATUS(status);
 727}
 728
 729/*******************************************************************************
 730 *
 731 * FUNCTION:    acpi_ds_eval_region_operands
 732 *
 733 * PARAMETERS:  walk_state      - Current walk
 734 *              Op              - A valid region Op object
 735 *
 736 * RETURN:      Status
 737 *
 738 * DESCRIPTION: Get region address and length
 739 *              Called from acpi_ds_exec_end_op during op_region parse tree walk
 740 *
 741 ******************************************************************************/
 742
 743acpi_status
 744acpi_ds_eval_region_operands(struct acpi_walk_state *walk_state,
 745                             union acpi_parse_object *op)
 746{
 747        acpi_status status;
 748        union acpi_operand_object *obj_desc;
 749        union acpi_operand_object *operand_desc;
 750        struct acpi_namespace_node *node;
 751        union acpi_parse_object *next_op;
 752
 753        ACPI_FUNCTION_TRACE_PTR(ds_eval_region_operands, op);
 754
 755        /*
 756         * This is where we evaluate the address and length fields of the
 757         * op_region declaration
 758         */
 759        node = op->common.node;
 760
 761        /* next_op points to the op that holds the space_iD */
 762
 763        next_op = op->common.value.arg;
 764
 765        /* next_op points to address op */
 766
 767        next_op = next_op->common.next;
 768
 769        /* Evaluate/create the address and length operands */
 770
 771        status = acpi_ds_create_operands(walk_state, next_op);
 772        if (ACPI_FAILURE(status)) {
 773                return_ACPI_STATUS(status);
 774        }
 775
 776        /* Resolve the length and address operands to numbers */
 777
 778        status = acpi_ex_resolve_operands(op->common.aml_opcode,
 779                                          ACPI_WALK_OPERANDS, walk_state);
 780        if (ACPI_FAILURE(status)) {
 781                return_ACPI_STATUS(status);
 782        }
 783
 784        obj_desc = acpi_ns_get_attached_object(node);
 785        if (!obj_desc) {
 786                return_ACPI_STATUS(AE_NOT_EXIST);
 787        }
 788
 789        /*
 790         * Get the length operand and save it
 791         * (at Top of stack)
 792         */
 793        operand_desc = walk_state->operands[walk_state->num_operands - 1];
 794
 795        obj_desc->region.length = (u32) operand_desc->integer.value;
 796        acpi_ut_remove_reference(operand_desc);
 797
 798        /*
 799         * Get the address and save it
 800         * (at top of stack - 1)
 801         */
 802        operand_desc = walk_state->operands[walk_state->num_operands - 2];
 803
 804        obj_desc->region.address = (acpi_physical_address)
 805            operand_desc->integer.value;
 806        acpi_ut_remove_reference(operand_desc);
 807
 808        ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "RgnObj %p Addr %8.8X%8.8X Len %X\n",
 809                          obj_desc,
 810                          ACPI_FORMAT_NATIVE_UINT(obj_desc->region.address),
 811                          obj_desc->region.length));
 812
 813        /* Now the address and length are valid for this opregion */
 814
 815        obj_desc->region.flags |= AOPOBJ_DATA_VALID;
 816
 817        return_ACPI_STATUS(status);
 818}
 819
 820/*******************************************************************************
 821 *
 822 * FUNCTION:    acpi_ds_eval_table_region_operands
 823 *
 824 * PARAMETERS:  walk_state      - Current walk
 825 *              Op              - A valid region Op object
 826 *
 827 * RETURN:      Status
 828 *
 829 * DESCRIPTION: Get region address and length
 830 *              Called from acpi_ds_exec_end_op during data_table_region parse tree walk
 831 *
 832 ******************************************************************************/
 833
 834acpi_status
 835acpi_ds_eval_table_region_operands(struct acpi_walk_state *walk_state,
 836                                   union acpi_parse_object *op)
 837{
 838        acpi_status status;
 839        union acpi_operand_object *obj_desc;
 840        union acpi_operand_object **operand;
 841        struct acpi_namespace_node *node;
 842        union acpi_parse_object *next_op;
 843        u32 table_index;
 844        struct acpi_table_header *table;
 845
 846        ACPI_FUNCTION_TRACE_PTR(ds_eval_table_region_operands, op);
 847
 848        /*
 849         * This is where we evaluate the signature_string and oem_iDString
 850         * and oem_table_iDString of the data_table_region declaration
 851         */
 852        node = op->common.node;
 853
 854        /* next_op points to signature_string op */
 855
 856        next_op = op->common.value.arg;
 857
 858        /*
 859         * Evaluate/create the signature_string and oem_iDString
 860         * and oem_table_iDString operands
 861         */
 862        status = acpi_ds_create_operands(walk_state, next_op);
 863        if (ACPI_FAILURE(status)) {
 864                return_ACPI_STATUS(status);
 865        }
 866
 867        /*
 868         * Resolve the signature_string and oem_iDString
 869         * and oem_table_iDString operands
 870         */
 871        status = acpi_ex_resolve_operands(op->common.aml_opcode,
 872                                          ACPI_WALK_OPERANDS, walk_state);
 873        if (ACPI_FAILURE(status)) {
 874                return_ACPI_STATUS(status);
 875        }
 876
 877        operand = &walk_state->operands[0];
 878
 879        /* Find the ACPI table */
 880
 881        status = acpi_tb_find_table(operand[0]->string.pointer,
 882                                    operand[1]->string.pointer,
 883                                    operand[2]->string.pointer, &table_index);
 884        if (ACPI_FAILURE(status)) {
 885                return_ACPI_STATUS(status);
 886        }
 887
 888        acpi_ut_remove_reference(operand[0]);
 889        acpi_ut_remove_reference(operand[1]);
 890        acpi_ut_remove_reference(operand[2]);
 891
 892        status = acpi_get_table_by_index(table_index, &table);
 893        if (ACPI_FAILURE(status)) {
 894                return_ACPI_STATUS(status);
 895        }
 896
 897        obj_desc = acpi_ns_get_attached_object(node);
 898        if (!obj_desc) {
 899                return_ACPI_STATUS(AE_NOT_EXIST);
 900        }
 901
 902        obj_desc->region.address =
 903            (acpi_physical_address) ACPI_TO_INTEGER(table);
 904        obj_desc->region.length = table->length;
 905
 906        ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "RgnObj %p Addr %8.8X%8.8X Len %X\n",
 907                          obj_desc,
 908                          ACPI_FORMAT_NATIVE_UINT(obj_desc->region.address),
 909                          obj_desc->region.length));
 910
 911        /* Now the address and length are valid for this opregion */
 912
 913        obj_desc->region.flags |= AOPOBJ_DATA_VALID;
 914
 915        return_ACPI_STATUS(status);
 916}
 917
 918/*******************************************************************************
 919 *
 920 * FUNCTION:    acpi_ds_eval_data_object_operands
 921 *
 922 * PARAMETERS:  walk_state      - Current walk
 923 *              Op              - A valid data_object Op object
 924 *              obj_desc        - data_object
 925 *
 926 * RETURN:      Status
 927 *
 928 * DESCRIPTION: Get the operands and complete the following data object types:
 929 *              Buffer, Package.
 930 *
 931 ******************************************************************************/
 932
 933acpi_status
 934acpi_ds_eval_data_object_operands(struct acpi_walk_state *walk_state,
 935                                  union acpi_parse_object *op,
 936                                  union acpi_operand_object *obj_desc)
 937{
 938        acpi_status status;
 939        union acpi_operand_object *arg_desc;
 940        u32 length;
 941
 942        ACPI_FUNCTION_TRACE(ds_eval_data_object_operands);
 943
 944        /* The first operand (for all of these data objects) is the length */
 945
 946        /*
 947         * Set proper index into operand stack for acpi_ds_obj_stack_push
 948         * invoked inside acpi_ds_create_operand.
 949         */
 950        walk_state->operand_index = walk_state->num_operands;
 951
 952        status = acpi_ds_create_operand(walk_state, op->common.value.arg, 1);
 953        if (ACPI_FAILURE(status)) {
 954                return_ACPI_STATUS(status);
 955        }
 956
 957        status = acpi_ex_resolve_operands(walk_state->opcode,
 958                                          &(walk_state->
 959                                            operands[walk_state->num_operands -
 960                                                     1]), walk_state);
 961        if (ACPI_FAILURE(status)) {
 962                return_ACPI_STATUS(status);
 963        }
 964
 965        /* Extract length operand */
 966
 967        arg_desc = walk_state->operands[walk_state->num_operands - 1];
 968        length = (u32) arg_desc->integer.value;
 969
 970        /* Cleanup for length operand */
 971
 972        status = acpi_ds_obj_stack_pop(1, walk_state);
 973        if (ACPI_FAILURE(status)) {
 974                return_ACPI_STATUS(status);
 975        }
 976
 977        acpi_ut_remove_reference(arg_desc);
 978
 979        /*
 980         * Create the actual data object
 981         */
 982        switch (op->common.aml_opcode) {
 983        case AML_BUFFER_OP:
 984
 985                status =
 986                    acpi_ds_build_internal_buffer_obj(walk_state, op, length,
 987                                                      &obj_desc);
 988                break;
 989
 990        case AML_PACKAGE_OP:
 991        case AML_VAR_PACKAGE_OP:
 992
 993                status =
 994                    acpi_ds_build_internal_package_obj(walk_state, op, length,
 995                                                       &obj_desc);
 996                break;
 997
 998        default:
 999                return_ACPI_STATUS(AE_AML_BAD_OPCODE);
1000        }
1001
1002        if (ACPI_SUCCESS(status)) {
1003                /*
1004                 * Return the object in the walk_state, unless the parent is a package -
1005                 * in this case, the return object will be stored in the parse tree
1006                 * for the package.
1007                 */
1008                if ((!op->common.parent) ||
1009                    ((op->common.parent->common.aml_opcode != AML_PACKAGE_OP) &&
1010                     (op->common.parent->common.aml_opcode !=
1011                      AML_VAR_PACKAGE_OP)
1012                     && (op->common.parent->common.aml_opcode != AML_NAME_OP))) {
1013                        walk_state->result_obj = obj_desc;
1014                }
1015        }
1016
1017        return_ACPI_STATUS(status);
1018}
1019
1020/*******************************************************************************
1021 *
1022 * FUNCTION:    acpi_ds_eval_bank_field_operands
1023 *
1024 * PARAMETERS:  walk_state      - Current walk
1025 *              Op              - A valid bank_field Op object
1026 *
1027 * RETURN:      Status
1028 *
1029 * DESCRIPTION: Get bank_field bank_value
1030 *              Called from acpi_ds_exec_end_op during bank_field parse tree walk
1031 *
1032 ******************************************************************************/
1033
1034acpi_status
1035acpi_ds_eval_bank_field_operands(struct acpi_walk_state *walk_state,
1036                                 union acpi_parse_object *op)
1037{
1038        acpi_status status;
1039        union acpi_operand_object *obj_desc;
1040        union acpi_operand_object *operand_desc;
1041        struct acpi_namespace_node *node;
1042        union acpi_parse_object *next_op;
1043        union acpi_parse_object *arg;
1044
1045        ACPI_FUNCTION_TRACE_PTR(ds_eval_bank_field_operands, op);
1046
1047        /*
1048         * This is where we evaluate the bank_value field of the
1049         * bank_field declaration
1050         */
1051
1052        /* next_op points to the op that holds the Region */
1053
1054        next_op = op->common.value.arg;
1055
1056        /* next_op points to the op that holds the Bank Register */
1057
1058        next_op = next_op->common.next;
1059
1060        /* next_op points to the op that holds the Bank Value */
1061
1062        next_op = next_op->common.next;
1063
1064        /*
1065         * Set proper index into operand stack for acpi_ds_obj_stack_push
1066         * invoked inside acpi_ds_create_operand.
1067         *
1068         * We use walk_state->Operands[0] to store the evaluated bank_value
1069         */
1070        walk_state->operand_index = 0;
1071
1072        status = acpi_ds_create_operand(walk_state, next_op, 0);
1073        if (ACPI_FAILURE(status)) {
1074                return_ACPI_STATUS(status);
1075        }
1076
1077        status = acpi_ex_resolve_to_value(&walk_state->operands[0], walk_state);
1078        if (ACPI_FAILURE(status)) {
1079                return_ACPI_STATUS(status);
1080        }
1081
1082        ACPI_DUMP_OPERANDS(ACPI_WALK_OPERANDS,
1083                           acpi_ps_get_opcode_name(op->common.aml_opcode), 1);
1084        /*
1085         * Get the bank_value operand and save it
1086         * (at Top of stack)
1087         */
1088        operand_desc = walk_state->operands[0];
1089
1090        /* Arg points to the start Bank Field */
1091
1092        arg = acpi_ps_get_arg(op, 4);
1093        while (arg) {
1094
1095                /* Ignore OFFSET and ACCESSAS terms here */
1096
1097                if (arg->common.aml_opcode == AML_INT_NAMEDFIELD_OP) {
1098                        node = arg->common.node;
1099
1100                        obj_desc = acpi_ns_get_attached_object(node);
1101                        if (!obj_desc) {
1102                                return_ACPI_STATUS(AE_NOT_EXIST);
1103                        }
1104
1105                        obj_desc->bank_field.value =
1106                            (u32) operand_desc->integer.value;
1107                }
1108
1109                /* Move to next field in the list */
1110
1111                arg = arg->common.next;
1112        }
1113
1114        acpi_ut_remove_reference(operand_desc);
1115        return_ACPI_STATUS(status);
1116}
1117
1118/*******************************************************************************
1119 *
1120 * FUNCTION:    acpi_ds_exec_begin_control_op
1121 *
1122 * PARAMETERS:  walk_list       - The list that owns the walk stack
1123 *              Op              - The control Op
1124 *
1125 * RETURN:      Status
1126 *
1127 * DESCRIPTION: Handles all control ops encountered during control method
1128 *              execution.
1129 *
1130 ******************************************************************************/
1131
1132acpi_status
1133acpi_ds_exec_begin_control_op(struct acpi_walk_state *walk_state,
1134                              union acpi_parse_object *op)
1135{
1136        acpi_status status = AE_OK;
1137        union acpi_generic_state *control_state;
1138
1139        ACPI_FUNCTION_NAME(ds_exec_begin_control_op);
1140
1141        ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH, "Op=%p Opcode=%2.2X State=%p\n", op,
1142                          op->common.aml_opcode, walk_state));
1143
1144        switch (op->common.aml_opcode) {
1145        case AML_WHILE_OP:
1146
1147                /*
1148                 * If this is an additional iteration of a while loop, continue.
1149                 * There is no need to allocate a new control state.
1150                 */
1151                if (walk_state->control_state) {
1152                        if (walk_state->control_state->control.aml_predicate_start
1153                                == (walk_state->parser_state.aml - 1)) {
1154
1155                                /* Reset the state to start-of-loop */
1156
1157                                walk_state->control_state->common.state =
1158                                    ACPI_CONTROL_CONDITIONAL_EXECUTING;
1159                                break;
1160                        }
1161                }
1162
1163                /*lint -fallthrough */
1164
1165        case AML_IF_OP:
1166
1167                /*
1168                 * IF/WHILE: Create a new control state to manage these
1169                 * constructs. We need to manage these as a stack, in order
1170                 * to handle nesting.
1171                 */
1172                control_state = acpi_ut_create_control_state();
1173                if (!control_state) {
1174                        status = AE_NO_MEMORY;
1175                        break;
1176                }
1177                /*
1178                 * Save a pointer to the predicate for multiple executions
1179                 * of a loop
1180                 */
1181                control_state->control.aml_predicate_start =
1182                    walk_state->parser_state.aml - 1;
1183                control_state->control.package_end =
1184                    walk_state->parser_state.pkg_end;
1185                control_state->control.opcode = op->common.aml_opcode;
1186
1187                /* Push the control state on this walk's control stack */
1188
1189                acpi_ut_push_generic_state(&walk_state->control_state,
1190                                           control_state);
1191                break;
1192
1193        case AML_ELSE_OP:
1194
1195                /* Predicate is in the state object */
1196                /* If predicate is true, the IF was executed, ignore ELSE part */
1197
1198                if (walk_state->last_predicate) {
1199                        status = AE_CTRL_TRUE;
1200                }
1201
1202                break;
1203
1204        case AML_RETURN_OP:
1205
1206                break;
1207
1208        default:
1209                break;
1210        }
1211
1212        return (status);
1213}
1214
1215/*******************************************************************************
1216 *
1217 * FUNCTION:    acpi_ds_exec_end_control_op
1218 *
1219 * PARAMETERS:  walk_list       - The list that owns the walk stack
1220 *              Op              - The control Op
1221 *
1222 * RETURN:      Status
1223 *
1224 * DESCRIPTION: Handles all control ops encountered during control method
1225 *              execution.
1226 *
1227 ******************************************************************************/
1228
1229acpi_status
1230acpi_ds_exec_end_control_op(struct acpi_walk_state * walk_state,
1231                            union acpi_parse_object * op)
1232{
1233        acpi_status status = AE_OK;
1234        union acpi_generic_state *control_state;
1235
1236        ACPI_FUNCTION_NAME(ds_exec_end_control_op);
1237
1238        switch (op->common.aml_opcode) {
1239        case AML_IF_OP:
1240
1241                ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH, "[IF_OP] Op=%p\n", op));
1242
1243                /*
1244                 * Save the result of the predicate in case there is an
1245                 * ELSE to come
1246                 */
1247                walk_state->last_predicate =
1248                    (u8) walk_state->control_state->common.value;
1249
1250                /*
1251                 * Pop the control state that was created at the start
1252                 * of the IF and free it
1253                 */
1254                control_state =
1255                    acpi_ut_pop_generic_state(&walk_state->control_state);
1256                acpi_ut_delete_generic_state(control_state);
1257                break;
1258
1259        case AML_ELSE_OP:
1260
1261                break;
1262
1263        case AML_WHILE_OP:
1264
1265                ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH, "[WHILE_OP] Op=%p\n", op));
1266
1267                control_state = walk_state->control_state;
1268                if (control_state->common.value) {
1269
1270                        /* Predicate was true, the body of the loop was just executed */
1271
1272                        /*
1273                         * This loop counter mechanism allows the interpreter to escape
1274                         * possibly infinite loops. This can occur in poorly written AML
1275                         * when the hardware does not respond within a while loop and the
1276                         * loop does not implement a timeout.
1277                         */
1278                        control_state->control.loop_count++;
1279                        if (control_state->control.loop_count >
1280                                ACPI_MAX_LOOP_ITERATIONS) {
1281                                status = AE_AML_INFINITE_LOOP;
1282                                break;
1283                        }
1284
1285                        /*
1286                         * Go back and evaluate the predicate and maybe execute the loop
1287                         * another time
1288                         */
1289                        status = AE_CTRL_PENDING;
1290                        walk_state->aml_last_while =
1291                            control_state->control.aml_predicate_start;
1292                        break;
1293                }
1294
1295                /* Predicate was false, terminate this while loop */
1296
1297                ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
1298                                  "[WHILE_OP] termination! Op=%p\n", op));
1299
1300                /* Pop this control state and free it */
1301
1302                control_state =
1303                    acpi_ut_pop_generic_state(&walk_state->control_state);
1304                acpi_ut_delete_generic_state(control_state);
1305                break;
1306
1307        case AML_RETURN_OP:
1308
1309                ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
1310                                  "[RETURN_OP] Op=%p Arg=%p\n", op,
1311                                  op->common.value.arg));
1312
1313                /*
1314                 * One optional operand -- the return value
1315                 * It can be either an immediate operand or a result that
1316                 * has been bubbled up the tree
1317                 */
1318                if (op->common.value.arg) {
1319
1320                        /* Since we have a real Return(), delete any implicit return */
1321
1322                        acpi_ds_clear_implicit_return(walk_state);
1323
1324                        /* Return statement has an immediate operand */
1325
1326                        status =
1327                            acpi_ds_create_operands(walk_state,
1328                                                    op->common.value.arg);
1329                        if (ACPI_FAILURE(status)) {
1330                                return (status);
1331                        }
1332
1333                        /*
1334                         * If value being returned is a Reference (such as
1335                         * an arg or local), resolve it now because it may
1336                         * cease to exist at the end of the method.
1337                         */
1338                        status =
1339                            acpi_ex_resolve_to_value(&walk_state->operands[0],
1340                                                     walk_state);
1341                        if (ACPI_FAILURE(status)) {
1342                                return (status);
1343                        }
1344
1345                        /*
1346                         * Get the return value and save as the last result
1347                         * value.  This is the only place where walk_state->return_desc
1348                         * is set to anything other than zero!
1349                         */
1350                        walk_state->return_desc = walk_state->operands[0];
1351                } else if (walk_state->result_count) {
1352
1353                        /* Since we have a real Return(), delete any implicit return */
1354
1355                        acpi_ds_clear_implicit_return(walk_state);
1356
1357                        /*
1358                         * The return value has come from a previous calculation.
1359                         *
1360                         * If value being returned is a Reference (such as
1361                         * an arg or local), resolve it now because it may
1362                         * cease to exist at the end of the method.
1363                         *
1364                         * Allow references created by the Index operator to return unchanged.
1365                         */
1366                        if ((ACPI_GET_DESCRIPTOR_TYPE
1367                             (walk_state->results->results.obj_desc[0]) ==
1368                             ACPI_DESC_TYPE_OPERAND)
1369                            && ((walk_state->results->results.obj_desc[0])->
1370                                common.type == ACPI_TYPE_LOCAL_REFERENCE)
1371                            && ((walk_state->results->results.obj_desc[0])->
1372                                reference.class != ACPI_REFCLASS_INDEX)) {
1373                                status =
1374                                    acpi_ex_resolve_to_value(&walk_state->
1375                                                             results->results.
1376                                                             obj_desc[0],
1377                                                             walk_state);
1378                                if (ACPI_FAILURE(status)) {
1379                                        return (status);
1380                                }
1381                        }
1382
1383                        walk_state->return_desc =
1384                            walk_state->results->results.obj_desc[0];
1385                } else {
1386                        /* No return operand */
1387
1388                        if (walk_state->num_operands) {
1389                                acpi_ut_remove_reference(walk_state->
1390                                                         operands[0]);
1391                        }
1392
1393                        walk_state->operands[0] = NULL;
1394                        walk_state->num_operands = 0;
1395                        walk_state->return_desc = NULL;
1396                }
1397
1398                ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
1399                                  "Completed RETURN_OP State=%p, RetVal=%p\n",
1400                                  walk_state, walk_state->return_desc));
1401
1402                /* End the control method execution right now */
1403
1404                status = AE_CTRL_TERMINATE;
1405                break;
1406
1407        case AML_NOOP_OP:
1408
1409                /* Just do nothing! */
1410                break;
1411
1412        case AML_BREAK_POINT_OP:
1413
1414                /*
1415                 * Set the single-step flag. This will cause the debugger (if present)
1416                 * to break to the console within the AML debugger at the start of the
1417                 * next AML instruction.
1418                 */
1419                ACPI_DEBUGGER_EXEC(acpi_gbl_cm_single_step = TRUE);
1420                ACPI_DEBUGGER_EXEC(acpi_os_printf
1421                                   ("**break** Executed AML BreakPoint opcode\n"));
1422
1423                /* Call to the OSL in case OS wants a piece of the action */
1424
1425                status = acpi_os_signal(ACPI_SIGNAL_BREAKPOINT,
1426                                        "Executed AML Breakpoint opcode");
1427                break;
1428
1429        case AML_BREAK_OP:
1430        case AML_CONTINUE_OP:   /* ACPI 2.0 */
1431
1432                /* Pop and delete control states until we find a while */
1433
1434                while (walk_state->control_state &&
1435                       (walk_state->control_state->control.opcode !=
1436                        AML_WHILE_OP)) {
1437                        control_state =
1438                            acpi_ut_pop_generic_state(&walk_state->
1439                                                      control_state);
1440                        acpi_ut_delete_generic_state(control_state);
1441                }
1442
1443                /* No while found? */
1444
1445                if (!walk_state->control_state) {
1446                        return (AE_AML_NO_WHILE);
1447                }
1448
1449                /* Was: walk_state->aml_last_while = walk_state->control_state->Control.aml_predicate_start; */
1450
1451                walk_state->aml_last_while =
1452                    walk_state->control_state->control.package_end;
1453
1454                /* Return status depending on opcode */
1455
1456                if (op->common.aml_opcode == AML_BREAK_OP) {
1457                        status = AE_CTRL_BREAK;
1458                } else {
1459                        status = AE_CTRL_CONTINUE;
1460                }
1461                break;
1462
1463        default:
1464
1465                ACPI_ERROR((AE_INFO, "Unknown control opcode=0x%X Op=%p",
1466                            op->common.aml_opcode, op));
1467
1468                status = AE_AML_BAD_OPCODE;
1469                break;
1470        }
1471
1472        return (status);
1473}
1474