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

   1/******************************************************************************
   2 *
   3 * Module Name: exresolv - AML Interpreter object resolution
   4 *
   5 *****************************************************************************/
   6
   7/*
   8 * Copyright (C) 2000 - 2016, 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 "amlcode.h"
  47#include "acdispat.h"
  48#include "acinterp.h"
  49#include "acnamesp.h"
  50
  51#define _COMPONENT          ACPI_EXECUTER
  52ACPI_MODULE_NAME("exresolv")
  53
  54/* Local prototypes */
  55static acpi_status
  56acpi_ex_resolve_object_to_value(union acpi_operand_object **stack_ptr,
  57                                struct acpi_walk_state *walk_state);
  58
  59/*******************************************************************************
  60 *
  61 * FUNCTION:    acpi_ex_resolve_to_value
  62 *
  63 * PARAMETERS:  **stack_ptr         - Points to entry on obj_stack, which can
  64 *                                    be either an (union acpi_operand_object *)
  65 *                                    or an acpi_handle.
  66 *              walk_state          - Current method state
  67 *
  68 * RETURN:      Status
  69 *
  70 * DESCRIPTION: Convert Reference objects to values
  71 *
  72 ******************************************************************************/
  73
  74acpi_status
  75acpi_ex_resolve_to_value(union acpi_operand_object **stack_ptr,
  76                         struct acpi_walk_state *walk_state)
  77{
  78        acpi_status status;
  79
  80        ACPI_FUNCTION_TRACE_PTR(ex_resolve_to_value, stack_ptr);
  81
  82        if (!stack_ptr || !*stack_ptr) {
  83                ACPI_ERROR((AE_INFO, "Internal - null pointer"));
  84                return_ACPI_STATUS(AE_AML_NO_OPERAND);
  85        }
  86
  87        /*
  88         * The entity pointed to by the stack_ptr can be either
  89         * 1) A valid union acpi_operand_object, or
  90         * 2) A struct acpi_namespace_node (named_obj)
  91         */
  92        if (ACPI_GET_DESCRIPTOR_TYPE(*stack_ptr) == ACPI_DESC_TYPE_OPERAND) {
  93                status = acpi_ex_resolve_object_to_value(stack_ptr, walk_state);
  94                if (ACPI_FAILURE(status)) {
  95                        return_ACPI_STATUS(status);
  96                }
  97
  98                if (!*stack_ptr) {
  99                        ACPI_ERROR((AE_INFO, "Internal - null pointer"));
 100                        return_ACPI_STATUS(AE_AML_NO_OPERAND);
 101                }
 102        }
 103
 104        /*
 105         * Object on the stack may have changed if acpi_ex_resolve_object_to_value()
 106         * was called (i.e., we can't use an _else_ here.)
 107         */
 108        if (ACPI_GET_DESCRIPTOR_TYPE(*stack_ptr) == ACPI_DESC_TYPE_NAMED) {
 109                status =
 110                    acpi_ex_resolve_node_to_value(ACPI_CAST_INDIRECT_PTR
 111                                                  (struct acpi_namespace_node,
 112                                                   stack_ptr), walk_state);
 113                if (ACPI_FAILURE(status)) {
 114                        return_ACPI_STATUS(status);
 115                }
 116        }
 117
 118        ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Resolved object %p\n", *stack_ptr));
 119        return_ACPI_STATUS(AE_OK);
 120}
 121
 122/*******************************************************************************
 123 *
 124 * FUNCTION:    acpi_ex_resolve_object_to_value
 125 *
 126 * PARAMETERS:  stack_ptr       - Pointer to an internal object
 127 *              walk_state      - Current method state
 128 *
 129 * RETURN:      Status
 130 *
 131 * DESCRIPTION: Retrieve the value from an internal object. The Reference type
 132 *              uses the associated AML opcode to determine the value.
 133 *
 134 ******************************************************************************/
 135
 136static acpi_status
 137acpi_ex_resolve_object_to_value(union acpi_operand_object **stack_ptr,
 138                                struct acpi_walk_state *walk_state)
 139{
 140        acpi_status status = AE_OK;
 141        union acpi_operand_object *stack_desc;
 142        union acpi_operand_object *obj_desc = NULL;
 143        u8 ref_type;
 144
 145        ACPI_FUNCTION_TRACE(ex_resolve_object_to_value);
 146
 147        stack_desc = *stack_ptr;
 148
 149        /* This is an object of type union acpi_operand_object */
 150
 151        switch (stack_desc->common.type) {
 152        case ACPI_TYPE_LOCAL_REFERENCE:
 153
 154                ref_type = stack_desc->reference.class;
 155
 156                switch (ref_type) {
 157                case ACPI_REFCLASS_LOCAL:
 158                case ACPI_REFCLASS_ARG:
 159                        /*
 160                         * Get the local from the method's state info
 161                         * Note: this increments the local's object reference count
 162                         */
 163                        status = acpi_ds_method_data_get_value(ref_type,
 164                                                               stack_desc->
 165                                                               reference.value,
 166                                                               walk_state,
 167                                                               &obj_desc);
 168                        if (ACPI_FAILURE(status)) {
 169                                return_ACPI_STATUS(status);
 170                        }
 171
 172                        ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
 173                                          "[Arg/Local %X] ValueObj is %p\n",
 174                                          stack_desc->reference.value,
 175                                          obj_desc));
 176
 177                        /*
 178                         * Now we can delete the original Reference Object and
 179                         * replace it with the resolved value
 180                         */
 181                        acpi_ut_remove_reference(stack_desc);
 182                        *stack_ptr = obj_desc;
 183                        break;
 184
 185                case ACPI_REFCLASS_INDEX:
 186
 187                        switch (stack_desc->reference.target_type) {
 188                        case ACPI_TYPE_BUFFER_FIELD:
 189
 190                                /* Just return - do not dereference */
 191                                break;
 192
 193                        case ACPI_TYPE_PACKAGE:
 194
 195                                /* If method call or copy_object - do not dereference */
 196
 197                                if ((walk_state->opcode ==
 198                                     AML_INT_METHODCALL_OP)
 199                                    || (walk_state->opcode == AML_COPY_OP)) {
 200                                        break;
 201                                }
 202
 203                                /* Otherwise, dereference the package_index to a package element */
 204
 205                                obj_desc = *stack_desc->reference.where;
 206                                if (obj_desc) {
 207                                        /*
 208                                         * Valid object descriptor, copy pointer to return value
 209                                         * (i.e., dereference the package index)
 210                                         * Delete the ref object, increment the returned object
 211                                         */
 212                                        acpi_ut_add_reference(obj_desc);
 213                                        *stack_ptr = obj_desc;
 214                                } else {
 215                                        /*
 216                                         * A NULL object descriptor means an uninitialized element of
 217                                         * the package, can't dereference it
 218                                         */
 219                                        ACPI_ERROR((AE_INFO,
 220                                                    "Attempt to dereference an Index to "
 221                                                    "NULL package element Idx=%p",
 222                                                    stack_desc));
 223                                        status = AE_AML_UNINITIALIZED_ELEMENT;
 224                                }
 225                                break;
 226
 227                        default:
 228
 229                                /* Invalid reference object */
 230
 231                                ACPI_ERROR((AE_INFO,
 232                                            "Unknown TargetType 0x%X in Index/Reference object %p",
 233                                            stack_desc->reference.target_type,
 234                                            stack_desc));
 235                                status = AE_AML_INTERNAL;
 236                                break;
 237                        }
 238                        break;
 239
 240                case ACPI_REFCLASS_REFOF:
 241                case ACPI_REFCLASS_DEBUG:
 242                case ACPI_REFCLASS_TABLE:
 243
 244                        /* Just leave the object as-is, do not dereference */
 245
 246                        break;
 247
 248                case ACPI_REFCLASS_NAME:        /* Reference to a named object */
 249
 250                        /* Dereference the name */
 251
 252                        if ((stack_desc->reference.node->type ==
 253                             ACPI_TYPE_DEVICE)
 254                            || (stack_desc->reference.node->type ==
 255                                ACPI_TYPE_THERMAL)) {
 256
 257                                /* These node types do not have 'real' subobjects */
 258
 259                                *stack_ptr = (void *)stack_desc->reference.node;
 260                        } else {
 261                                /* Get the object pointed to by the namespace node */
 262
 263                                *stack_ptr =
 264                                    (stack_desc->reference.node)->object;
 265                                acpi_ut_add_reference(*stack_ptr);
 266                        }
 267
 268                        acpi_ut_remove_reference(stack_desc);
 269                        break;
 270
 271                default:
 272
 273                        ACPI_ERROR((AE_INFO,
 274                                    "Unknown Reference type 0x%X in %p",
 275                                    ref_type, stack_desc));
 276                        status = AE_AML_INTERNAL;
 277                        break;
 278                }
 279                break;
 280
 281        case ACPI_TYPE_BUFFER:
 282
 283                status = acpi_ds_get_buffer_arguments(stack_desc);
 284                break;
 285
 286        case ACPI_TYPE_PACKAGE:
 287
 288                status = acpi_ds_get_package_arguments(stack_desc);
 289                break;
 290
 291        case ACPI_TYPE_BUFFER_FIELD:
 292        case ACPI_TYPE_LOCAL_REGION_FIELD:
 293        case ACPI_TYPE_LOCAL_BANK_FIELD:
 294        case ACPI_TYPE_LOCAL_INDEX_FIELD:
 295
 296                ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
 297                                  "FieldRead SourceDesc=%p Type=%X\n",
 298                                  stack_desc, stack_desc->common.type));
 299
 300                status =
 301                    acpi_ex_read_data_from_field(walk_state, stack_desc,
 302                                                 &obj_desc);
 303
 304                /* Remove a reference to the original operand, then override */
 305
 306                acpi_ut_remove_reference(*stack_ptr);
 307                *stack_ptr = (void *)obj_desc;
 308                break;
 309
 310        default:
 311
 312                break;
 313        }
 314
 315        return_ACPI_STATUS(status);
 316}
 317
 318/*******************************************************************************
 319 *
 320 * FUNCTION:    acpi_ex_resolve_multiple
 321 *
 322 * PARAMETERS:  walk_state          - Current state (contains AML opcode)
 323 *              operand             - Starting point for resolution
 324 *              return_type         - Where the object type is returned
 325 *              return_desc         - Where the resolved object is returned
 326 *
 327 * RETURN:      Status
 328 *
 329 * DESCRIPTION: Return the base object and type. Traverse a reference list if
 330 *              necessary to get to the base object.
 331 *
 332 ******************************************************************************/
 333
 334acpi_status
 335acpi_ex_resolve_multiple(struct acpi_walk_state *walk_state,
 336                         union acpi_operand_object *operand,
 337                         acpi_object_type *return_type,
 338                         union acpi_operand_object **return_desc)
 339{
 340        union acpi_operand_object *obj_desc = ACPI_CAST_PTR(void, operand);
 341        struct acpi_namespace_node *node =
 342            ACPI_CAST_PTR(struct acpi_namespace_node, operand);
 343        acpi_object_type type;
 344        acpi_status status;
 345
 346        ACPI_FUNCTION_TRACE(acpi_ex_resolve_multiple);
 347
 348        /* Operand can be either a namespace node or an operand descriptor */
 349
 350        switch (ACPI_GET_DESCRIPTOR_TYPE(obj_desc)) {
 351        case ACPI_DESC_TYPE_OPERAND:
 352
 353                type = obj_desc->common.type;
 354                break;
 355
 356        case ACPI_DESC_TYPE_NAMED:
 357
 358                type = ((struct acpi_namespace_node *)obj_desc)->type;
 359                obj_desc = acpi_ns_get_attached_object(node);
 360
 361                /* If we had an Alias node, use the attached object for type info */
 362
 363                if (type == ACPI_TYPE_LOCAL_ALIAS) {
 364                        type = ((struct acpi_namespace_node *)obj_desc)->type;
 365                        obj_desc = acpi_ns_get_attached_object((struct
 366                                                                acpi_namespace_node
 367                                                                *)obj_desc);
 368                }
 369
 370                if (!obj_desc) {
 371                        ACPI_ERROR((AE_INFO,
 372                                    "[%4.4s] Node is unresolved or uninitialized",
 373                                    acpi_ut_get_node_name(node)));
 374                        return_ACPI_STATUS(AE_AML_UNINITIALIZED_NODE);
 375                }
 376                break;
 377
 378        default:
 379                return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
 380        }
 381
 382        /* If type is anything other than a reference, we are done */
 383
 384        if (type != ACPI_TYPE_LOCAL_REFERENCE) {
 385                goto exit;
 386        }
 387
 388        /*
 389         * For reference objects created via the ref_of, Index, or Load/load_table
 390         * operators, we need to get to the base object (as per the ACPI
 391         * specification of the object_type and size_of operators). This means
 392         * traversing the list of possibly many nested references.
 393         */
 394        while (obj_desc->common.type == ACPI_TYPE_LOCAL_REFERENCE) {
 395                switch (obj_desc->reference.class) {
 396                case ACPI_REFCLASS_REFOF:
 397                case ACPI_REFCLASS_NAME:
 398
 399                        /* Dereference the reference pointer */
 400
 401                        if (obj_desc->reference.class == ACPI_REFCLASS_REFOF) {
 402                                node = obj_desc->reference.object;
 403                        } else {        /* AML_INT_NAMEPATH_OP */
 404
 405                                node = obj_desc->reference.node;
 406                        }
 407
 408                        /* All "References" point to a NS node */
 409
 410                        if (ACPI_GET_DESCRIPTOR_TYPE(node) !=
 411                            ACPI_DESC_TYPE_NAMED) {
 412                                ACPI_ERROR((AE_INFO,
 413                                            "Not a namespace node %p [%s]",
 414                                            node,
 415                                            acpi_ut_get_descriptor_name(node)));
 416                                return_ACPI_STATUS(AE_AML_INTERNAL);
 417                        }
 418
 419                        /* Get the attached object */
 420
 421                        obj_desc = acpi_ns_get_attached_object(node);
 422                        if (!obj_desc) {
 423
 424                                /* No object, use the NS node type */
 425
 426                                type = acpi_ns_get_type(node);
 427                                goto exit;
 428                        }
 429
 430                        /* Check for circular references */
 431
 432                        if (obj_desc == operand) {
 433                                return_ACPI_STATUS(AE_AML_CIRCULAR_REFERENCE);
 434                        }
 435                        break;
 436
 437                case ACPI_REFCLASS_INDEX:
 438
 439                        /* Get the type of this reference (index into another object) */
 440
 441                        type = obj_desc->reference.target_type;
 442                        if (type != ACPI_TYPE_PACKAGE) {
 443                                goto exit;
 444                        }
 445
 446                        /*
 447                         * The main object is a package, we want to get the type
 448                         * of the individual package element that is referenced by
 449                         * the index.
 450                         *
 451                         * This could of course in turn be another reference object.
 452                         */
 453                        obj_desc = *(obj_desc->reference.where);
 454                        if (!obj_desc) {
 455
 456                                /* NULL package elements are allowed */
 457
 458                                type = 0;       /* Uninitialized */
 459                                goto exit;
 460                        }
 461                        break;
 462
 463                case ACPI_REFCLASS_TABLE:
 464
 465                        type = ACPI_TYPE_DDB_HANDLE;
 466                        goto exit;
 467
 468                case ACPI_REFCLASS_LOCAL:
 469                case ACPI_REFCLASS_ARG:
 470
 471                        if (return_desc) {
 472                                status =
 473                                    acpi_ds_method_data_get_value(obj_desc->
 474                                                                  reference.
 475                                                                  class,
 476                                                                  obj_desc->
 477                                                                  reference.
 478                                                                  value,
 479                                                                  walk_state,
 480                                                                  &obj_desc);
 481                                if (ACPI_FAILURE(status)) {
 482                                        return_ACPI_STATUS(status);
 483                                }
 484                                acpi_ut_remove_reference(obj_desc);
 485                        } else {
 486                                status =
 487                                    acpi_ds_method_data_get_node(obj_desc->
 488                                                                 reference.
 489                                                                 class,
 490                                                                 obj_desc->
 491                                                                 reference.
 492                                                                 value,
 493                                                                 walk_state,
 494                                                                 &node);
 495                                if (ACPI_FAILURE(status)) {
 496                                        return_ACPI_STATUS(status);
 497                                }
 498
 499                                obj_desc = acpi_ns_get_attached_object(node);
 500                                if (!obj_desc) {
 501                                        type = ACPI_TYPE_ANY;
 502                                        goto exit;
 503                                }
 504                        }
 505                        break;
 506
 507                case ACPI_REFCLASS_DEBUG:
 508
 509                        /* The Debug Object is of type "DebugObject" */
 510
 511                        type = ACPI_TYPE_DEBUG_OBJECT;
 512                        goto exit;
 513
 514                default:
 515
 516                        ACPI_ERROR((AE_INFO,
 517                                    "Unknown Reference Class 0x%2.2X",
 518                                    obj_desc->reference.class));
 519                        return_ACPI_STATUS(AE_AML_INTERNAL);
 520                }
 521        }
 522
 523        /*
 524         * Now we are guaranteed to have an object that has not been created
 525         * via the ref_of or Index operators.
 526         */
 527        type = obj_desc->common.type;
 528
 529exit:
 530        /* Convert internal types to external types */
 531
 532        switch (type) {
 533        case ACPI_TYPE_LOCAL_REGION_FIELD:
 534        case ACPI_TYPE_LOCAL_BANK_FIELD:
 535        case ACPI_TYPE_LOCAL_INDEX_FIELD:
 536
 537                type = ACPI_TYPE_FIELD_UNIT;
 538                break;
 539
 540        case ACPI_TYPE_LOCAL_SCOPE:
 541
 542                /* Per ACPI Specification, Scope is untyped */
 543
 544                type = ACPI_TYPE_ANY;
 545                break;
 546
 547        default:
 548
 549                /* No change to Type required */
 550
 551                break;
 552        }
 553
 554        *return_type = type;
 555        if (return_desc) {
 556                *return_desc = obj_desc;
 557        }
 558        return_ACPI_STATUS(AE_OK);
 559}
 560