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

   1/******************************************************************************
   2 *
   3 * Module Name: exprep - ACPI AML (p-code) execution - field prep utilities
   4 *
   5 *****************************************************************************/
   6
   7/*
   8 * Copyright (C) 2000 - 2013, 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 "acinterp.h"
  47#include "amlcode.h"
  48#include "acnamesp.h"
  49#include "acdispat.h"
  50
  51#define _COMPONENT          ACPI_EXECUTER
  52ACPI_MODULE_NAME("exprep")
  53
  54/* Local prototypes */
  55static u32
  56acpi_ex_decode_field_access(union acpi_operand_object *obj_desc,
  57                            u8 field_flags, u32 * return_byte_alignment);
  58
  59#ifdef ACPI_UNDER_DEVELOPMENT
  60
  61static u32
  62acpi_ex_generate_access(u32 field_bit_offset,
  63                        u32 field_bit_length, u32 region_length);
  64
  65/*******************************************************************************
  66 *
  67 * FUNCTION:    acpi_ex_generate_access
  68 *
  69 * PARAMETERS:  field_bit_offset    - Start of field within parent region/buffer
  70 *              field_bit_length    - Length of field in bits
  71 *              region_length       - Length of parent in bytes
  72 *
  73 * RETURN:      Field granularity (8, 16, 32 or 64) and
  74 *              byte_alignment (1, 2, 3, or 4)
  75 *
  76 * DESCRIPTION: Generate an optimal access width for fields defined with the
  77 *              any_acc keyword.
  78 *
  79 * NOTE: Need to have the region_length in order to check for boundary
  80 *       conditions (end-of-region). However, the region_length is a deferred
  81 *       operation. Therefore, to complete this implementation, the generation
  82 *       of this access width must be deferred until the region length has
  83 *       been evaluated.
  84 *
  85 ******************************************************************************/
  86
  87static u32
  88acpi_ex_generate_access(u32 field_bit_offset,
  89                        u32 field_bit_length, u32 region_length)
  90{
  91        u32 field_byte_length;
  92        u32 field_byte_offset;
  93        u32 field_byte_end_offset;
  94        u32 access_byte_width;
  95        u32 field_start_offset;
  96        u32 field_end_offset;
  97        u32 minimum_access_width = 0xFFFFFFFF;
  98        u32 minimum_accesses = 0xFFFFFFFF;
  99        u32 accesses;
 100
 101        ACPI_FUNCTION_TRACE(ex_generate_access);
 102
 103        /* Round Field start offset and length to "minimal" byte boundaries */
 104
 105        field_byte_offset = ACPI_DIV_8(ACPI_ROUND_DOWN(field_bit_offset, 8));
 106        field_byte_end_offset = ACPI_DIV_8(ACPI_ROUND_UP(field_bit_length +
 107                                                         field_bit_offset, 8));
 108        field_byte_length = field_byte_end_offset - field_byte_offset;
 109
 110        ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 111                          "Bit length %u, Bit offset %u\n",
 112                          field_bit_length, field_bit_offset));
 113
 114        ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 115                          "Byte Length %u, Byte Offset %u, End Offset %u\n",
 116                          field_byte_length, field_byte_offset,
 117                          field_byte_end_offset));
 118
 119        /*
 120         * Iterative search for the maximum access width that is both aligned
 121         * and does not go beyond the end of the region
 122         *
 123         * Start at byte_acc and work upwards to qword_acc max. (1,2,4,8 bytes)
 124         */
 125        for (access_byte_width = 1; access_byte_width <= 8;
 126             access_byte_width <<= 1) {
 127                /*
 128                 * 1) Round end offset up to next access boundary and make sure that
 129                 *    this does not go beyond the end of the parent region.
 130                 * 2) When the Access width is greater than the field_byte_length, we
 131                 *    are done. (This does not optimize for the perfectly aligned
 132                 *    case yet).
 133                 */
 134                if (ACPI_ROUND_UP(field_byte_end_offset, access_byte_width) <=
 135                    region_length) {
 136                        field_start_offset =
 137                            ACPI_ROUND_DOWN(field_byte_offset,
 138                                            access_byte_width) /
 139                            access_byte_width;
 140
 141                        field_end_offset =
 142                            ACPI_ROUND_UP((field_byte_length +
 143                                           field_byte_offset),
 144                                          access_byte_width) /
 145                            access_byte_width;
 146
 147                        accesses = field_end_offset - field_start_offset;
 148
 149                        ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 150                                          "AccessWidth %u end is within region\n",
 151                                          access_byte_width));
 152
 153                        ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 154                                          "Field Start %u, Field End %u -- requires %u accesses\n",
 155                                          field_start_offset, field_end_offset,
 156                                          accesses));
 157
 158                        /* Single access is optimal */
 159
 160                        if (accesses <= 1) {
 161                                ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 162                                                  "Entire field can be accessed with one operation of size %u\n",
 163                                                  access_byte_width));
 164                                return_VALUE(access_byte_width);
 165                        }
 166
 167                        /*
 168                         * Fits in the region, but requires more than one read/write.
 169                         * try the next wider access on next iteration
 170                         */
 171                        if (accesses < minimum_accesses) {
 172                                minimum_accesses = accesses;
 173                                minimum_access_width = access_byte_width;
 174                        }
 175                } else {
 176                        ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 177                                          "AccessWidth %u end is NOT within region\n",
 178                                          access_byte_width));
 179                        if (access_byte_width == 1) {
 180                                ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 181                                                  "Field goes beyond end-of-region!\n"));
 182
 183                                /* Field does not fit in the region at all */
 184
 185                                return_VALUE(0);
 186                        }
 187
 188                        /*
 189                         * This width goes beyond the end-of-region, back off to
 190                         * previous access
 191                         */
 192                        ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 193                                          "Backing off to previous optimal access width of %u\n",
 194                                          minimum_access_width));
 195                        return_VALUE(minimum_access_width);
 196                }
 197        }
 198
 199        /*
 200         * Could not read/write field with one operation,
 201         * just use max access width
 202         */
 203        ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 204                          "Cannot access field in one operation, using width 8\n"));
 205        return_VALUE(8);
 206}
 207#endif                          /* ACPI_UNDER_DEVELOPMENT */
 208
 209/*******************************************************************************
 210 *
 211 * FUNCTION:    acpi_ex_decode_field_access
 212 *
 213 * PARAMETERS:  obj_desc            - Field object
 214 *              field_flags         - Encoded fieldflags (contains access bits)
 215 *              return_byte_alignment - Where the byte alignment is returned
 216 *
 217 * RETURN:      Field granularity (8, 16, 32 or 64) and
 218 *              byte_alignment (1, 2, 3, or 4)
 219 *
 220 * DESCRIPTION: Decode the access_type bits of a field definition.
 221 *
 222 ******************************************************************************/
 223
 224static u32
 225acpi_ex_decode_field_access(union acpi_operand_object *obj_desc,
 226                            u8 field_flags, u32 * return_byte_alignment)
 227{
 228        u32 access;
 229        u32 byte_alignment;
 230        u32 bit_length;
 231
 232        ACPI_FUNCTION_TRACE(ex_decode_field_access);
 233
 234        access = (field_flags & AML_FIELD_ACCESS_TYPE_MASK);
 235
 236        switch (access) {
 237        case AML_FIELD_ACCESS_ANY:
 238
 239#ifdef ACPI_UNDER_DEVELOPMENT
 240                byte_alignment =
 241                    acpi_ex_generate_access(obj_desc->common_field.
 242                                            start_field_bit_offset,
 243                                            obj_desc->common_field.bit_length,
 244                                            0xFFFFFFFF
 245                                            /* Temp until we pass region_length as parameter */
 246                    );
 247                bit_length = byte_alignment * 8;
 248#endif
 249
 250                byte_alignment = 1;
 251                bit_length = 8;
 252                break;
 253
 254        case AML_FIELD_ACCESS_BYTE:
 255        case AML_FIELD_ACCESS_BUFFER:   /* ACPI 2.0 (SMBus Buffer) */
 256
 257                byte_alignment = 1;
 258                bit_length = 8;
 259                break;
 260
 261        case AML_FIELD_ACCESS_WORD:
 262
 263                byte_alignment = 2;
 264                bit_length = 16;
 265                break;
 266
 267        case AML_FIELD_ACCESS_DWORD:
 268
 269                byte_alignment = 4;
 270                bit_length = 32;
 271                break;
 272
 273        case AML_FIELD_ACCESS_QWORD:    /* ACPI 2.0 */
 274
 275                byte_alignment = 8;
 276                bit_length = 64;
 277                break;
 278
 279        default:
 280
 281                /* Invalid field access type */
 282
 283                ACPI_ERROR((AE_INFO, "Unknown field access type 0x%X", access));
 284                return_UINT32(0);
 285        }
 286
 287        if (obj_desc->common.type == ACPI_TYPE_BUFFER_FIELD) {
 288                /*
 289                 * buffer_field access can be on any byte boundary, so the
 290                 * byte_alignment is always 1 byte -- regardless of any byte_alignment
 291                 * implied by the field access type.
 292                 */
 293                byte_alignment = 1;
 294        }
 295
 296        *return_byte_alignment = byte_alignment;
 297        return_UINT32(bit_length);
 298}
 299
 300/*******************************************************************************
 301 *
 302 * FUNCTION:    acpi_ex_prep_common_field_object
 303 *
 304 * PARAMETERS:  obj_desc            - The field object
 305 *              field_flags         - Access, lock_rule, and update_rule.
 306 *                                    The format of a field_flag is described
 307 *                                    in the ACPI specification
 308 *              field_attribute     - Special attributes (not used)
 309 *              field_bit_position  - Field start position
 310 *              field_bit_length    - Field length in number of bits
 311 *
 312 * RETURN:      Status
 313 *
 314 * DESCRIPTION: Initialize the areas of the field object that are common
 315 *              to the various types of fields. Note: This is very "sensitive"
 316 *              code because we are solving the general case for field
 317 *              alignment.
 318 *
 319 ******************************************************************************/
 320
 321acpi_status
 322acpi_ex_prep_common_field_object(union acpi_operand_object *obj_desc,
 323                                 u8 field_flags,
 324                                 u8 field_attribute,
 325                                 u32 field_bit_position, u32 field_bit_length)
 326{
 327        u32 access_bit_width;
 328        u32 byte_alignment;
 329        u32 nearest_byte_address;
 330
 331        ACPI_FUNCTION_TRACE(ex_prep_common_field_object);
 332
 333        /*
 334         * Note: the structure being initialized is the
 335         * ACPI_COMMON_FIELD_INFO;  No structure fields outside of the common
 336         * area are initialized by this procedure.
 337         */
 338        obj_desc->common_field.field_flags = field_flags;
 339        obj_desc->common_field.attribute = field_attribute;
 340        obj_desc->common_field.bit_length = field_bit_length;
 341
 342        /*
 343         * Decode the access type so we can compute offsets. The access type gives
 344         * two pieces of information - the width of each field access and the
 345         * necessary byte_alignment (address granularity) of the access.
 346         *
 347         * For any_acc, the access_bit_width is the largest width that is both
 348         * necessary and possible in an attempt to access the whole field in one
 349         * I/O operation. However, for any_acc, the byte_alignment is always one
 350         * byte.
 351         *
 352         * For all Buffer Fields, the byte_alignment is always one byte.
 353         *
 354         * For all other access types (Byte, Word, Dword, Qword), the Bitwidth is
 355         * the same (equivalent) as the byte_alignment.
 356         */
 357        access_bit_width = acpi_ex_decode_field_access(obj_desc, field_flags,
 358                                                       &byte_alignment);
 359        if (!access_bit_width) {
 360                return_ACPI_STATUS(AE_AML_OPERAND_VALUE);
 361        }
 362
 363        /* Setup width (access granularity) fields (values are: 1, 2, 4, 8) */
 364
 365        obj_desc->common_field.access_byte_width = (u8)
 366            ACPI_DIV_8(access_bit_width);
 367
 368        /*
 369         * base_byte_offset is the address of the start of the field within the
 370         * region. It is the byte address of the first *datum* (field-width data
 371         * unit) of the field. (i.e., the first datum that contains at least the
 372         * first *bit* of the field.)
 373         *
 374         * Note: byte_alignment is always either equal to the access_bit_width or 8
 375         * (Byte access), and it defines the addressing granularity of the parent
 376         * region or buffer.
 377         */
 378        nearest_byte_address =
 379            ACPI_ROUND_BITS_DOWN_TO_BYTES(field_bit_position);
 380        obj_desc->common_field.base_byte_offset = (u32)
 381            ACPI_ROUND_DOWN(nearest_byte_address, byte_alignment);
 382
 383        /*
 384         * start_field_bit_offset is the offset of the first bit of the field within
 385         * a field datum.
 386         */
 387        obj_desc->common_field.start_field_bit_offset = (u8)
 388            (field_bit_position -
 389             ACPI_MUL_8(obj_desc->common_field.base_byte_offset));
 390
 391        return_ACPI_STATUS(AE_OK);
 392}
 393
 394/*******************************************************************************
 395 *
 396 * FUNCTION:    acpi_ex_prep_field_value
 397 *
 398 * PARAMETERS:  info    - Contains all field creation info
 399 *
 400 * RETURN:      Status
 401 *
 402 * DESCRIPTION: Construct an object of type union acpi_operand_object with a
 403 *              subtype of def_field and connect it to the parent Node.
 404 *
 405 ******************************************************************************/
 406
 407acpi_status acpi_ex_prep_field_value(struct acpi_create_field_info *info)
 408{
 409        union acpi_operand_object *obj_desc;
 410        union acpi_operand_object *second_desc = NULL;
 411        acpi_status status;
 412        u32 access_byte_width;
 413        u32 type;
 414
 415        ACPI_FUNCTION_TRACE(ex_prep_field_value);
 416
 417        /* Parameter validation */
 418
 419        if (info->field_type != ACPI_TYPE_LOCAL_INDEX_FIELD) {
 420                if (!info->region_node) {
 421                        ACPI_ERROR((AE_INFO, "Null RegionNode"));
 422                        return_ACPI_STATUS(AE_AML_NO_OPERAND);
 423                }
 424
 425                type = acpi_ns_get_type(info->region_node);
 426                if (type != ACPI_TYPE_REGION) {
 427                        ACPI_ERROR((AE_INFO,
 428                                    "Needed Region, found type 0x%X (%s)", type,
 429                                    acpi_ut_get_type_name(type)));
 430
 431                        return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
 432                }
 433        }
 434
 435        /* Allocate a new field object */
 436
 437        obj_desc = acpi_ut_create_internal_object(info->field_type);
 438        if (!obj_desc) {
 439                return_ACPI_STATUS(AE_NO_MEMORY);
 440        }
 441
 442        /* Initialize areas of the object that are common to all fields */
 443
 444        obj_desc->common_field.node = info->field_node;
 445        status = acpi_ex_prep_common_field_object(obj_desc,
 446                                                  info->field_flags,
 447                                                  info->attribute,
 448                                                  info->field_bit_position,
 449                                                  info->field_bit_length);
 450        if (ACPI_FAILURE(status)) {
 451                acpi_ut_delete_object_desc(obj_desc);
 452                return_ACPI_STATUS(status);
 453        }
 454
 455        /* Initialize areas of the object that are specific to the field type */
 456
 457        switch (info->field_type) {
 458        case ACPI_TYPE_LOCAL_REGION_FIELD:
 459
 460                obj_desc->field.region_obj =
 461                    acpi_ns_get_attached_object(info->region_node);
 462
 463                /* Fields specific to generic_serial_bus fields */
 464
 465                obj_desc->field.access_length = info->access_length;
 466
 467                if (info->connection_node) {
 468                        second_desc = info->connection_node->object;
 469                        if (!(second_desc->common.flags & AOPOBJ_DATA_VALID)) {
 470                                status =
 471                                    acpi_ds_get_buffer_arguments(second_desc);
 472                                if (ACPI_FAILURE(status)) {
 473                                        acpi_ut_delete_object_desc(obj_desc);
 474                                        return_ACPI_STATUS(status);
 475                                }
 476                        }
 477
 478                        obj_desc->field.resource_buffer =
 479                            second_desc->buffer.pointer;
 480                        obj_desc->field.resource_length =
 481                            (u16)second_desc->buffer.length;
 482                } else if (info->resource_buffer) {
 483                        obj_desc->field.resource_buffer = info->resource_buffer;
 484                        obj_desc->field.resource_length = info->resource_length;
 485                }
 486
 487                /* Allow full data read from EC address space */
 488
 489                if ((obj_desc->field.region_obj->region.space_id ==
 490                     ACPI_ADR_SPACE_EC)
 491                    && (obj_desc->common_field.bit_length > 8)) {
 492                        access_byte_width =
 493                            ACPI_ROUND_BITS_UP_TO_BYTES(obj_desc->common_field.
 494                                                        bit_length);
 495
 496                        /* Maximum byte width supported is 255 */
 497
 498                        if (access_byte_width < 256) {
 499                                obj_desc->common_field.access_byte_width =
 500                                    (u8)access_byte_width;
 501                        }
 502                }
 503                /* An additional reference for the container */
 504
 505                acpi_ut_add_reference(obj_desc->field.region_obj);
 506
 507                ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 508                                  "RegionField: BitOff %X, Off %X, Gran %X, Region %p\n",
 509                                  obj_desc->field.start_field_bit_offset,
 510                                  obj_desc->field.base_byte_offset,
 511                                  obj_desc->field.access_byte_width,
 512                                  obj_desc->field.region_obj));
 513                break;
 514
 515        case ACPI_TYPE_LOCAL_BANK_FIELD:
 516
 517                obj_desc->bank_field.value = info->bank_value;
 518                obj_desc->bank_field.region_obj =
 519                    acpi_ns_get_attached_object(info->region_node);
 520                obj_desc->bank_field.bank_obj =
 521                    acpi_ns_get_attached_object(info->register_node);
 522
 523                /* An additional reference for the attached objects */
 524
 525                acpi_ut_add_reference(obj_desc->bank_field.region_obj);
 526                acpi_ut_add_reference(obj_desc->bank_field.bank_obj);
 527
 528                ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 529                                  "Bank Field: BitOff %X, Off %X, Gran %X, Region %p, BankReg %p\n",
 530                                  obj_desc->bank_field.start_field_bit_offset,
 531                                  obj_desc->bank_field.base_byte_offset,
 532                                  obj_desc->field.access_byte_width,
 533                                  obj_desc->bank_field.region_obj,
 534                                  obj_desc->bank_field.bank_obj));
 535
 536                /*
 537                 * Remember location in AML stream of the field unit
 538                 * opcode and operands -- since the bank_value
 539                 * operands must be evaluated.
 540                 */
 541                second_desc = obj_desc->common.next_object;
 542                second_desc->extra.aml_start =
 543                    ACPI_CAST_PTR(union acpi_parse_object,
 544                                  info->data_register_node)->named.data;
 545                second_desc->extra.aml_length =
 546                    ACPI_CAST_PTR(union acpi_parse_object,
 547                                  info->data_register_node)->named.length;
 548
 549                break;
 550
 551        case ACPI_TYPE_LOCAL_INDEX_FIELD:
 552
 553                /* Get the Index and Data registers */
 554
 555                obj_desc->index_field.index_obj =
 556                    acpi_ns_get_attached_object(info->register_node);
 557                obj_desc->index_field.data_obj =
 558                    acpi_ns_get_attached_object(info->data_register_node);
 559
 560                if (!obj_desc->index_field.data_obj
 561                    || !obj_desc->index_field.index_obj) {
 562                        ACPI_ERROR((AE_INFO,
 563                                    "Null Index Object during field prep"));
 564                        acpi_ut_delete_object_desc(obj_desc);
 565                        return_ACPI_STATUS(AE_AML_INTERNAL);
 566                }
 567
 568                /* An additional reference for the attached objects */
 569
 570                acpi_ut_add_reference(obj_desc->index_field.data_obj);
 571                acpi_ut_add_reference(obj_desc->index_field.index_obj);
 572
 573                /*
 574                 * April 2006: Changed to match MS behavior
 575                 *
 576                 * The value written to the Index register is the byte offset of the
 577                 * target field in units of the granularity of the index_field
 578                 *
 579                 * Previously, the value was calculated as an index in terms of the
 580                 * width of the Data register, as below:
 581                 *
 582                 *      obj_desc->index_field.Value = (u32)
 583                 *          (Info->field_bit_position / ACPI_MUL_8 (
 584                 *              obj_desc->Field.access_byte_width));
 585                 *
 586                 * February 2006: Tried value as a byte offset:
 587                 *      obj_desc->index_field.Value = (u32)
 588                 *          ACPI_DIV_8 (Info->field_bit_position);
 589                 */
 590                obj_desc->index_field.value =
 591                    (u32) ACPI_ROUND_DOWN(ACPI_DIV_8(info->field_bit_position),
 592                                          obj_desc->index_field.
 593                                          access_byte_width);
 594
 595                ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 596                                  "IndexField: BitOff %X, Off %X, Value %X, Gran %X, Index %p, Data %p\n",
 597                                  obj_desc->index_field.start_field_bit_offset,
 598                                  obj_desc->index_field.base_byte_offset,
 599                                  obj_desc->index_field.value,
 600                                  obj_desc->field.access_byte_width,
 601                                  obj_desc->index_field.index_obj,
 602                                  obj_desc->index_field.data_obj));
 603                break;
 604
 605        default:
 606
 607                /* No other types should get here */
 608
 609                break;
 610        }
 611
 612        /*
 613         * Store the constructed descriptor (obj_desc) into the parent Node,
 614         * preserving the current type of that named_obj.
 615         */
 616        status = acpi_ns_attach_object(info->field_node, obj_desc,
 617                                       acpi_ns_get_type(info->field_node));
 618
 619        ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 620                          "Set NamedObj %p [%4.4s], ObjDesc %p\n",
 621                          info->field_node,
 622                          acpi_ut_get_node_name(info->field_node), obj_desc));
 623
 624        /* Remove local reference to the object */
 625
 626        acpi_ut_remove_reference(obj_desc);
 627        return_ACPI_STATUS(status);
 628}
 629