git.oblomov.eu Git - linux-2.6/blob - drivers/acpi/dispatcher/dsobject.c

   1 /******************************************************************************
   2  *
   3  * Module Name: dsobject - Dispatcher object management routines
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2008, 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 <acpi/acparser.h>
  46 #include <acpi/amlcode.h>
  47 #include <acpi/acdispat.h>
  48 #include <acpi/acnamesp.h>
  49 #include <acpi/acinterp.h>
  50
  51 #define _COMPONENT          ACPI_DISPATCHER
  52 ACPI_MODULE_NAME("dsobject")
  53
  54 /* Local prototypes */
  55 static acpi_status
  56 acpi_ds_build_internal_object(struct acpi_walk_state *walk_state,
  57                               union acpi_parse_object *op,
  58                               union acpi_operand_object **obj_desc_ptr);
  59
  60 #ifndef ACPI_NO_METHOD_EXECUTION
  61 /*******************************************************************************
  62  *
  63  * FUNCTION:    acpi_ds_build_internal_object
  64  *
  65  * PARAMETERS:  walk_state      - Current walk state
  66  *              Op              - Parser object to be translated
  67  *              obj_desc_ptr    - Where the ACPI internal object is returned
  68  *
  69  * RETURN:      Status
  70  *
  71  * DESCRIPTION: Translate a parser Op object to the equivalent namespace object
  72  *              Simple objects are any objects other than a package object!
  73  *
  74  ******************************************************************************/
  75
  76 static acpi_status
  77 acpi_ds_build_internal_object(struct acpi_walk_state *walk_state,
  78                               union acpi_parse_object *op,
  79                               union acpi_operand_object **obj_desc_ptr)
  80 {
  81         union acpi_operand_object *obj_desc;
  82         acpi_status status;
  83
  84         ACPI_FUNCTION_TRACE(ds_build_internal_object);
  85
  86         *obj_desc_ptr = NULL;
  87         if (op->common.aml_opcode == AML_INT_NAMEPATH_OP) {
  88                 /*
  89                  * This is a named object reference. If this name was
  90                  * previously looked up in the namespace, it was stored in this op.
  91                  * Otherwise, go ahead and look it up now
  92                  */
  93                 if (!op->common.node) {
  94                         status = acpi_ns_lookup(walk_state->scope_info,
  95                                                 op->common.value.string,
  96                                                 ACPI_TYPE_ANY,
  97                                                 ACPI_IMODE_EXECUTE,
  98                                                 ACPI_NS_SEARCH_PARENT |
  99                                                 ACPI_NS_DONT_OPEN_SCOPE, NULL,
 100                                                 ACPI_CAST_INDIRECT_PTR(struct
 101                                                                        acpi_namespace_node,
 102                                                                        &(op->
 103                                                                          common.
 104                                                                          node)));
 105                         if (ACPI_FAILURE(status)) {
 106
 107                                 /* Check if we are resolving a named reference within a package */
 108
 109                                 if ((status == AE_NOT_FOUND)
 110                                     && (acpi_gbl_enable_interpreter_slack)
 111                                     &&
 112                                     ((op->common.parent->common.aml_opcode ==
 113                                       AML_PACKAGE_OP)
 114                                      || (op->common.parent->common.aml_opcode ==
 115                                          AML_VAR_PACKAGE_OP))) {
 116                                         /*
 117                                          * We didn't find the target and we are populating elements
 118                                          * of a package - ignore if slack enabled. Some ASL code
 119                                          * contains dangling invalid references in packages and
 120                                          * expects that no exception will be issued. Leave the
 121                                          * element as a null element. It cannot be used, but it
 122                                          * can be overwritten by subsequent ASL code - this is
 123                                          * typically the case.
 124                                          */
 125                                         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 126                                                           "Ignoring unresolved reference in package [%4.4s]\n",
 127                                                           walk_state->
 128                                                           scope_info->scope.
 129                                                           node->name.ascii));
 130
 131                                         return_ACPI_STATUS(AE_OK);
 132                                 } else {
 133                                         ACPI_ERROR_NAMESPACE(op->common.value.
 134                                                              string, status);
 135                                 }
 136
 137                                 return_ACPI_STATUS(status);
 138                         }
 139                 }
 140
 141                 /* Special object resolution for elements of a package */
 142
 143                 if ((op->common.parent->common.aml_opcode == AML_PACKAGE_OP) ||
 144                     (op->common.parent->common.aml_opcode ==
 145                      AML_VAR_PACKAGE_OP)) {
 146                         /*
 147                          * Attempt to resolve the node to a value before we insert it into
 148                          * the package. If this is a reference to a common data type,
 149                          * resolve it immediately. According to the ACPI spec, package
 150                          * elements can only be "data objects" or method references.
 151                          * Attempt to resolve to an Integer, Buffer, String or Package.
 152                          * If cannot, return the named reference (for things like Devices,
 153                          * Methods, etc.) Buffer Fields and Fields will resolve to simple
 154                          * objects (int/buf/str/pkg).
 155                          *
 156                          * NOTE: References to things like Devices, Methods, Mutexes, etc.
 157                          * will remain as named references. This behavior is not described
 158                          * in the ACPI spec, but it appears to be an oversight.
 159                          */
 160                         obj_desc =
 161                             ACPI_CAST_PTR(union acpi_operand_object,
 162                                           op->common.node);
 163
 164                         status =
 165                             acpi_ex_resolve_node_to_value(ACPI_CAST_INDIRECT_PTR
 166                                                           (struct
 167                                                            acpi_namespace_node,
 168                                                            &obj_desc),
 169                                                           walk_state);
 170                         if (ACPI_FAILURE(status)) {
 171                                 return_ACPI_STATUS(status);
 172                         }
 173
 174                         switch (op->common.node->type) {
 175                                 /*
 176                                  * For these types, we need the actual node, not the subobject.
 177                                  * However, the subobject did not get an extra reference count above.
 178                                  *
 179                                  * TBD: should ex_resolve_node_to_value be changed to fix this?
 180                                  */
 181                         case ACPI_TYPE_DEVICE:
 182                         case ACPI_TYPE_THERMAL:
 183
 184                                 acpi_ut_add_reference(op->common.node->object);
 185
 186                                 /*lint -fallthrough */
 187                                 /*
 188                                  * For these types, we need the actual node, not the subobject.
 189                                  * The subobject got an extra reference count in ex_resolve_node_to_value.
 190                                  */
 191                         case ACPI_TYPE_MUTEX:
 192                         case ACPI_TYPE_METHOD:
 193                         case ACPI_TYPE_POWER:
 194                         case ACPI_TYPE_PROCESSOR:
 195                         case ACPI_TYPE_EVENT:
 196                         case ACPI_TYPE_REGION:
 197
 198                                 /* We will create a reference object for these types below */
 199                                 break;
 200
 201                         default:
 202                                 /*
 203                                  * All other types - the node was resolved to an actual
 204                                  * object, we are done.
 205                                  */
 206                                 goto exit;
 207                         }
 208                 }
 209         }
 210
 211         /* Create and init a new internal ACPI object */
 212
 213         obj_desc = acpi_ut_create_internal_object((acpi_ps_get_opcode_info
 214                                                    (op->common.aml_opcode))->
 215                                                   object_type);
 216         if (!obj_desc) {
 217                 return_ACPI_STATUS(AE_NO_MEMORY);
 218         }
 219
 220         status =
 221             acpi_ds_init_object_from_op(walk_state, op, op->common.aml_opcode,
 222                                         &obj_desc);
 223         if (ACPI_FAILURE(status)) {
 224                 acpi_ut_remove_reference(obj_desc);
 225                 return_ACPI_STATUS(status);
 226         }
 227
 228       exit:
 229         *obj_desc_ptr = obj_desc;
 230         return_ACPI_STATUS(status);
 231 }
 232
 233 /*******************************************************************************
 234  *
 235  * FUNCTION:    acpi_ds_build_internal_buffer_obj
 236  *
 237  * PARAMETERS:  walk_state      - Current walk state
 238  *              Op              - Parser object to be translated
 239  *              buffer_length   - Length of the buffer
 240  *              obj_desc_ptr    - Where the ACPI internal object is returned
 241  *
 242  * RETURN:      Status
 243  *
 244  * DESCRIPTION: Translate a parser Op package object to the equivalent
 245  *              namespace object
 246  *
 247  ******************************************************************************/
 248
 249 acpi_status
 250 acpi_ds_build_internal_buffer_obj(struct acpi_walk_state *walk_state,
 251                                   union acpi_parse_object *op,
 252                                   u32 buffer_length,
 253                                   union acpi_operand_object **obj_desc_ptr)
 254 {
 255         union acpi_parse_object *arg;
 256         union acpi_operand_object *obj_desc;
 257         union acpi_parse_object *byte_list;
 258         u32 byte_list_length = 0;
 259
 260         ACPI_FUNCTION_TRACE(ds_build_internal_buffer_obj);
 261
 262         /*
 263          * If we are evaluating a Named buffer object "Name (xxxx, Buffer)".
 264          * The buffer object already exists (from the NS node), otherwise it must
 265          * be created.
 266          */
 267         obj_desc = *obj_desc_ptr;
 268         if (!obj_desc) {
 269
 270                 /* Create a new buffer object */
 271
 272                 obj_desc = acpi_ut_create_internal_object(ACPI_TYPE_BUFFER);
 273                 *obj_desc_ptr = obj_desc;
 274                 if (!obj_desc) {
 275                         return_ACPI_STATUS(AE_NO_MEMORY);
 276                 }
 277         }
 278
 279         /*
 280          * Second arg is the buffer data (optional) byte_list can be either
 281          * individual bytes or a string initializer.  In either case, a
 282          * byte_list appears in the AML.
 283          */
 284         arg = op->common.value.arg;     /* skip first arg */
 285
 286         byte_list = arg->named.next;
 287         if (byte_list) {
 288                 if (byte_list->common.aml_opcode != AML_INT_BYTELIST_OP) {
 289                         ACPI_ERROR((AE_INFO,
 290                                     "Expecting bytelist, got AML opcode %X in op %p",
 291                                     byte_list->common.aml_opcode, byte_list));
 292
 293                         acpi_ut_remove_reference(obj_desc);
 294                         return (AE_TYPE);
 295                 }
 296
 297                 byte_list_length = (u32) byte_list->common.value.integer;
 298         }
 299
 300         /*
 301          * The buffer length (number of bytes) will be the larger of:
 302          * 1) The specified buffer length and
 303          * 2) The length of the initializer byte list
 304          */
 305         obj_desc->buffer.length = buffer_length;
 306         if (byte_list_length > buffer_length) {
 307                 obj_desc->buffer.length = byte_list_length;
 308         }
 309
 310         /* Allocate the buffer */
 311
 312         if (obj_desc->buffer.length == 0) {
 313                 obj_desc->buffer.pointer = NULL;
 314                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
 315                                   "Buffer defined with zero length in AML, creating\n"));
 316         } else {
 317                 obj_desc->buffer.pointer =
 318                     ACPI_ALLOCATE_ZEROED(obj_desc->buffer.length);
 319                 if (!obj_desc->buffer.pointer) {
 320                         acpi_ut_delete_object_desc(obj_desc);
 321                         return_ACPI_STATUS(AE_NO_MEMORY);
 322                 }
 323
 324                 /* Initialize buffer from the byte_list (if present) */
 325
 326                 if (byte_list) {
 327                         ACPI_MEMCPY(obj_desc->buffer.pointer,
 328                                     byte_list->named.data, byte_list_length);
 329                 }
 330         }
 331
 332         obj_desc->buffer.flags |= AOPOBJ_DATA_VALID;
 333         op->common.node = ACPI_CAST_PTR(struct acpi_namespace_node, obj_desc);
 334         return_ACPI_STATUS(AE_OK);
 335 }
 336
 337 /*******************************************************************************
 338  *
 339  * FUNCTION:    acpi_ds_build_internal_package_obj
 340  *
 341  * PARAMETERS:  walk_state      - Current walk state
 342  *              Op              - Parser object to be translated
 343  *              element_count   - Number of elements in the package - this is
 344  *                                the num_elements argument to Package()
 345  *              obj_desc_ptr    - Where the ACPI internal object is returned
 346  *
 347  * RETURN:      Status
 348  *
 349  * DESCRIPTION: Translate a parser Op package object to the equivalent
 350  *              namespace object
 351  *
 352  * NOTE: The number of elements in the package will be always be the num_elements
 353  * count, regardless of the number of elements in the package list. If
 354  * num_elements is smaller, only that many package list elements are used.
 355  * if num_elements is larger, the Package object is padded out with
 356  * objects of type Uninitialized (as per ACPI spec.)
 357  *
 358  * Even though the ASL compilers do not allow num_elements to be smaller
 359  * than the Package list length (for the fixed length package opcode), some
 360  * BIOS code modifies the AML on the fly to adjust the num_elements, and
 361  * this code compensates for that. This also provides compatibility with
 362  * other AML interpreters.
 363  *
 364  ******************************************************************************/
 365
 366 acpi_status
 367 acpi_ds_build_internal_package_obj(struct acpi_walk_state *walk_state,
 368                                    union acpi_parse_object *op,
 369                                    u32 element_count,
 370                                    union acpi_operand_object **obj_desc_ptr)
 371 {
 372         union acpi_parse_object *arg;
 373         union acpi_parse_object *parent;
 374         union acpi_operand_object *obj_desc = NULL;
 375         acpi_status status = AE_OK;
 376         unsigned i;
 377         u16 index;
 378         u16 reference_count;
 379
 380         ACPI_FUNCTION_TRACE(ds_build_internal_package_obj);
 381
 382         /* Find the parent of a possibly nested package */
 383
 384         parent = op->common.parent;
 385         while ((parent->common.aml_opcode == AML_PACKAGE_OP) ||
 386                (parent->common.aml_opcode == AML_VAR_PACKAGE_OP)) {
 387                 parent = parent->common.parent;
 388         }
 389
 390         /*
 391          * If we are evaluating a Named package object "Name (xxxx, Package)",
 392          * the package object already exists, otherwise it must be created.
 393          */
 394         obj_desc = *obj_desc_ptr;
 395         if (!obj_desc) {
 396                 obj_desc = acpi_ut_create_internal_object(ACPI_TYPE_PACKAGE);
 397                 *obj_desc_ptr = obj_desc;
 398                 if (!obj_desc) {
 399                         return_ACPI_STATUS(AE_NO_MEMORY);
 400                 }
 401
 402                 obj_desc->package.node = parent->common.node;
 403         }
 404
 405         /*
 406          * Allocate the element array (array of pointers to the individual
 407          * objects) based on the num_elements parameter. Add an extra pointer slot
 408          * so that the list is always null terminated.
 409          */
 410         obj_desc->package.elements = ACPI_ALLOCATE_ZEROED(((acpi_size)
 411                                                            element_count +
 412                                                            1) * sizeof(void *));
 413
 414         if (!obj_desc->package.elements) {
 415                 acpi_ut_delete_object_desc(obj_desc);
 416                 return_ACPI_STATUS(AE_NO_MEMORY);
 417         }
 418
 419         obj_desc->package.count = element_count;
 420
 421         /*
 422          * Initialize the elements of the package, up to the num_elements count.
 423          * Package is automatically padded with uninitialized (NULL) elements
 424          * if num_elements is greater than the package list length. Likewise,
 425          * Package is truncated if num_elements is less than the list length.
 426          */
 427         arg = op->common.value.arg;
 428         arg = arg->common.next;
 429         for (i = 0; arg && (i < element_count); i++) {
 430                 if (arg->common.aml_opcode == AML_INT_RETURN_VALUE_OP) {
 431                         if (arg->common.node->type == ACPI_TYPE_METHOD) {
 432                                 /*
 433                                  * A method reference "looks" to the parser to be a method
 434                                  * invocation, so we special case it here
 435                                  */
 436                                 arg->common.aml_opcode = AML_INT_NAMEPATH_OP;
 437                                 status =
 438                                     acpi_ds_build_internal_object(walk_state,
 439                                                                   arg,
 440                                                                   &obj_desc->
 441                                                                   package.
 442                                                                   elements[i]);
 443                         } else {
 444                                 /* This package element is already built, just get it */
 445
 446                                 obj_desc->package.elements[i] =
 447                                     ACPI_CAST_PTR(union acpi_operand_object,
 448                                                   arg->common.node);
 449                         }
 450                 } else {
 451                         status = acpi_ds_build_internal_object(walk_state, arg,
 452                                                                &obj_desc->
 453                                                                package.
 454                                                                elements[i]);
 455                 }
 456
 457                 if (*obj_desc_ptr) {
 458
 459                         /* Existing package, get existing reference count */
 460
 461                         reference_count =
 462                             (*obj_desc_ptr)->common.reference_count;
 463                         if (reference_count > 1) {
 464
 465                                 /* Make new element ref count match original ref count */
 466
 467                                 for (index = 0; index < (reference_count - 1);
 468                                      index++) {
 469                                         acpi_ut_add_reference((obj_desc->
 470                                                                package.
 471                                                                elements[i]));
 472                                 }
 473                         }
 474                 }
 475
 476                 arg = arg->common.next;
 477         }
 478
 479         /* Check for match between num_elements and actual length of package_list */
 480
 481         if (arg) {
 482                 /*
 483                  * num_elements was exhausted, but there are remaining elements in the
 484                  * package_list.
 485                  *
 486                  * Note: technically, this is an error, from ACPI spec: "It is an error
 487                  * for NumElements to be less than the number of elements in the
 488                  * PackageList". However, for now, we just print an error message and
 489                  * no exception is returned.
 490                  */
 491                 while (arg) {
 492
 493                         /* Find out how many elements there really are */
 494
 495                         i++;
 496                         arg = arg->common.next;
 497                 }
 498
 499                 ACPI_ERROR((AE_INFO,
 500                             "Package List length (%X) larger than NumElements count (%X), truncated\n",
 501                             i, element_count));
 502         } else if (i < element_count) {
 503                 /*
 504                  * Arg list (elements) was exhausted, but we did not reach num_elements count.
 505                  * Note: this is not an error, the package is padded out with NULLs.
 506                  */
 507                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 508                                   "Package List length (%X) smaller than NumElements count (%X), padded with null elements\n",
 509                                   i, element_count));
 510         }
 511
 512         obj_desc->package.flags |= AOPOBJ_DATA_VALID;
 513         op->common.node = ACPI_CAST_PTR(struct acpi_namespace_node, obj_desc);
 514         return_ACPI_STATUS(status);
 515 }
 516
 517 /*******************************************************************************
 518  *
 519  * FUNCTION:    acpi_ds_create_node
 520  *
 521  * PARAMETERS:  walk_state      - Current walk state
 522  *              Node            - NS Node to be initialized
 523  *              Op              - Parser object to be translated
 524  *
 525  * RETURN:      Status
 526  *
 527  * DESCRIPTION: Create the object to be associated with a namespace node
 528  *
 529  ******************************************************************************/
 530
 531 acpi_status
 532 acpi_ds_create_node(struct acpi_walk_state *walk_state,
 533                     struct acpi_namespace_node *node,
 534                     union acpi_parse_object *op)
 535 {
 536         acpi_status status;
 537         union acpi_operand_object *obj_desc;
 538
 539         ACPI_FUNCTION_TRACE_PTR(ds_create_node, op);
 540
 541         /*
 542          * Because of the execution pass through the non-control-method
 543          * parts of the table, we can arrive here twice.  Only init
 544          * the named object node the first time through
 545          */
 546         if (acpi_ns_get_attached_object(node)) {
 547                 return_ACPI_STATUS(AE_OK);
 548         }
 549
 550         if (!op->common.value.arg) {
 551
 552                 /* No arguments, there is nothing to do */
 553
 554                 return_ACPI_STATUS(AE_OK);
 555         }
 556
 557         /* Build an internal object for the argument(s) */
 558
 559         status = acpi_ds_build_internal_object(walk_state, op->common.value.arg,
 560                                                &obj_desc);
 561         if (ACPI_FAILURE(status)) {
 562                 return_ACPI_STATUS(status);
 563         }
 564
 565         /* Re-type the object according to its argument */
 566
 567         node->type = ACPI_GET_OBJECT_TYPE(obj_desc);
 568
 569         /* Attach obj to node */
 570
 571         status = acpi_ns_attach_object(node, obj_desc, node->type);
 572
 573         /* Remove local reference to the object */
 574
 575         acpi_ut_remove_reference(obj_desc);
 576         return_ACPI_STATUS(status);
 577 }
 578
 579 #endif                          /* ACPI_NO_METHOD_EXECUTION */
 580
 581 /*******************************************************************************
 582  *
 583  * FUNCTION:    acpi_ds_init_object_from_op
 584  *
 585  * PARAMETERS:  walk_state      - Current walk state
 586  *              Op              - Parser op used to init the internal object
 587  *              Opcode          - AML opcode associated with the object
 588  *              ret_obj_desc    - Namespace object to be initialized
 589  *
 590  * RETURN:      Status
 591  *
 592  * DESCRIPTION: Initialize a namespace object from a parser Op and its
 593  *              associated arguments.  The namespace object is a more compact
 594  *              representation of the Op and its arguments.
 595  *
 596  ******************************************************************************/
 597
 598 acpi_status
 599 acpi_ds_init_object_from_op(struct acpi_walk_state *walk_state,
 600                             union acpi_parse_object *op,
 601                             u16 opcode,
 602                             union acpi_operand_object **ret_obj_desc)
 603 {
 604         const struct acpi_opcode_info *op_info;
 605         union acpi_operand_object *obj_desc;
 606         acpi_status status = AE_OK;
 607
 608         ACPI_FUNCTION_TRACE(ds_init_object_from_op);
 609
 610         obj_desc = *ret_obj_desc;
 611         op_info = acpi_ps_get_opcode_info(opcode);
 612         if (op_info->class == AML_CLASS_UNKNOWN) {
 613
 614                 /* Unknown opcode */
 615
 616                 return_ACPI_STATUS(AE_TYPE);
 617         }
 618
 619         /* Perform per-object initialization */
 620
 621         switch (ACPI_GET_OBJECT_TYPE(obj_desc)) {
 622         case ACPI_TYPE_BUFFER:
 623
 624                 /*
 625                  * Defer evaluation of Buffer term_arg operand
 626                  */
 627                 obj_desc->buffer.node =
 628                     ACPI_CAST_PTR(struct acpi_namespace_node,
 629                                   walk_state->operands[0]);
 630                 obj_desc->buffer.aml_start = op->named.data;
 631                 obj_desc->buffer.aml_length = op->named.length;
 632                 break;
 633
 634         case ACPI_TYPE_PACKAGE:
 635
 636                 /*
 637                  * Defer evaluation of Package term_arg operand
 638                  */
 639                 obj_desc->package.node =
 640                     ACPI_CAST_PTR(struct acpi_namespace_node,
 641                                   walk_state->operands[0]);
 642                 obj_desc->package.aml_start = op->named.data;
 643                 obj_desc->package.aml_length = op->named.length;
 644                 break;
 645
 646         case ACPI_TYPE_INTEGER:
 647
 648                 switch (op_info->type) {
 649                 case AML_TYPE_CONSTANT:
 650                         /*
 651                          * Resolve AML Constants here - AND ONLY HERE!
 652                          * All constants are integers.
 653                          * We mark the integer with a flag that indicates that it started
 654                          * life as a constant -- so that stores to constants will perform
 655                          * as expected (noop). zero_op is used as a placeholder for optional
 656                          * target operands.
 657                          */
 658                         obj_desc->common.flags = AOPOBJ_AML_CONSTANT;
 659
 660                         switch (opcode) {
 661                         case AML_ZERO_OP:
 662
 663                                 obj_desc->integer.value = 0;
 664                                 break;
 665
 666                         case AML_ONE_OP:
 667
 668                                 obj_desc->integer.value = 1;
 669                                 break;
 670
 671                         case AML_ONES_OP:
 672
 673                                 obj_desc->integer.value = ACPI_INTEGER_MAX;
 674
 675                                 /* Truncate value if we are executing from a 32-bit ACPI table */
 676
 677 #ifndef ACPI_NO_METHOD_EXECUTION
 678                                 acpi_ex_truncate_for32bit_table(obj_desc);
 679 #endif
 680                                 break;
 681
 682                         case AML_REVISION_OP:
 683
 684                                 obj_desc->integer.value = ACPI_CA_VERSION;
 685                                 break;
 686
 687                         default:
 688
 689                                 ACPI_ERROR((AE_INFO,
 690                                             "Unknown constant opcode %X",
 691                                             opcode));
 692                                 status = AE_AML_OPERAND_TYPE;
 693                                 break;
 694                         }
 695                         break;
 696
 697                 case AML_TYPE_LITERAL:
 698
 699                         obj_desc->integer.value = op->common.value.integer;
 700 #ifndef ACPI_NO_METHOD_EXECUTION
 701                         acpi_ex_truncate_for32bit_table(obj_desc);
 702 #endif
 703                         break;
 704
 705                 default:
 706                         ACPI_ERROR((AE_INFO, "Unknown Integer type %X",
 707                                     op_info->type));
 708                         status = AE_AML_OPERAND_TYPE;
 709                         break;
 710                 }
 711                 break;
 712
 713         case ACPI_TYPE_STRING:
 714
 715                 obj_desc->string.pointer = op->common.value.string;
 716                 obj_desc->string.length =
 717                     (u32) ACPI_STRLEN(op->common.value.string);
 718
 719                 /*
 720                  * The string is contained in the ACPI table, don't ever try
 721                  * to delete it
 722                  */
 723                 obj_desc->common.flags |= AOPOBJ_STATIC_POINTER;
 724                 break;
 725
 726         case ACPI_TYPE_METHOD:
 727                 break;
 728
 729         case ACPI_TYPE_LOCAL_REFERENCE:
 730
 731                 switch (op_info->type) {
 732                 case AML_TYPE_LOCAL_VARIABLE:
 733
 734                         /* Split the opcode into a base opcode + offset */
 735
 736                         obj_desc->reference.opcode = AML_LOCAL_OP;
 737                         obj_desc->reference.offset = opcode - AML_LOCAL_OP;
 738
 739 #ifndef ACPI_NO_METHOD_EXECUTION
 740                         status = acpi_ds_method_data_get_node(AML_LOCAL_OP,
 741                                                               obj_desc->
 742                                                               reference.offset,
 743                                                               walk_state,
 744                                                               (struct
 745                                                                acpi_namespace_node
 746                                                                **)&obj_desc->
 747                                                               reference.object);
 748 #endif
 749                         break;
 750
 751                 case AML_TYPE_METHOD_ARGUMENT:
 752
 753                         /* Split the opcode into a base opcode + offset */
 754
 755                         obj_desc->reference.opcode = AML_ARG_OP;
 756                         obj_desc->reference.offset = opcode - AML_ARG_OP;
 757
 758 #ifndef ACPI_NO_METHOD_EXECUTION
 759                         status = acpi_ds_method_data_get_node(AML_ARG_OP,
 760                                                               obj_desc->
 761                                                               reference.offset,
 762                                                               walk_state,
 763                                                               (struct
 764                                                                acpi_namespace_node
 765                                                                **)&obj_desc->
 766                                                               reference.object);
 767 #endif
 768                         break;
 769
 770                 default:        /* Other literals, etc.. */
 771
 772                         if (op->common.aml_opcode == AML_INT_NAMEPATH_OP) {
 773
 774                                 /* Node was saved in Op */
 775
 776                                 obj_desc->reference.node = op->common.node;
 777                                 obj_desc->reference.object =
 778                                     op->common.node->object;
 779                         }
 780
 781                         obj_desc->reference.opcode = opcode;
 782                         break;
 783                 }
 784                 break;
 785
 786         default:
 787
 788                 ACPI_ERROR((AE_INFO, "Unimplemented data type: %X",
 789                             ACPI_GET_OBJECT_TYPE(obj_desc)));
 790
 791                 status = AE_AML_OPERAND_TYPE;
 792                 break;
 793         }
 794
 795         return_ACPI_STATUS(status);
 796 }