drivers/acpi/acpica/exresolv.c

   1 /******************************************************************************
   2  *
   3  * Module Name: exresolv - AML Interpreter object resolution
   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 "amlcode.h"
  47 #include "acdispat.h"
  48 #include "acinterp.h"
  49 #include "acnamesp.h"
  50
  51 #define _COMPONENT          ACPI_EXECUTER
  52 ACPI_MODULE_NAME("exresolv")
  53
  54 /* Local prototypes */
  55 static acpi_status
  56 acpi_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
  74 acpi_status
  75 acpi_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
 136 static acpi_status
 137 acpi_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_remove_reference(stack_desc);
 213                                         acpi_ut_add_reference(obj_desc);
 214                                         *stack_ptr = obj_desc;
 215                                 } else {
 216                                         /*
 217                                          * A NULL object descriptor means an uninitialized element of
 218                                          * the package, can't dereference it
 219                                          */
 220                                         ACPI_ERROR((AE_INFO,
 221                                                     "Attempt to dereference an Index to 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
 334 acpi_status
 335 acpi_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 = (void *)operand;
 341         struct acpi_namespace_node *node;
 342         acpi_object_type type;
 343         acpi_status status;
 344
 345         ACPI_FUNCTION_TRACE(acpi_ex_resolve_multiple);
 346
 347         /* Operand can be either a namespace node or an operand descriptor */
 348
 349         switch (ACPI_GET_DESCRIPTOR_TYPE(obj_desc)) {
 350         case ACPI_DESC_TYPE_OPERAND:
 351
 352                 type = obj_desc->common.type;
 353                 break;
 354
 355         case ACPI_DESC_TYPE_NAMED:
 356
 357                 type = ((struct acpi_namespace_node *)obj_desc)->type;
 358                 obj_desc =
 359                     acpi_ns_get_attached_object((struct acpi_namespace_node *)
 360                                                 obj_desc);
 361
 362                 /* If we had an Alias node, use the attached object for type info */
 363
 364                 if (type == ACPI_TYPE_LOCAL_ALIAS) {
 365                         type = ((struct acpi_namespace_node *)obj_desc)->type;
 366                         obj_desc =
 367                             acpi_ns_get_attached_object((struct
 368                                                          acpi_namespace_node *)
 369                                                         obj_desc);
 370                 }
 371                 break;
 372
 373         default:
 374                 return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
 375         }
 376
 377         /* If type is anything other than a reference, we are done */
 378
 379         if (type != ACPI_TYPE_LOCAL_REFERENCE) {
 380                 goto exit;
 381         }
 382
 383         /*
 384          * For reference objects created via the ref_of, Index, or Load/load_table
 385          * operators, we need to get to the base object (as per the ACPI
 386          * specification of the object_type and size_of operators). This means
 387          * traversing the list of possibly many nested references.
 388          */
 389         while (obj_desc->common.type == ACPI_TYPE_LOCAL_REFERENCE) {
 390                 switch (obj_desc->reference.class) {
 391                 case ACPI_REFCLASS_REFOF:
 392                 case ACPI_REFCLASS_NAME:
 393
 394                         /* Dereference the reference pointer */
 395
 396                         if (obj_desc->reference.class == ACPI_REFCLASS_REFOF) {
 397                                 node = obj_desc->reference.object;
 398                         } else {        /* AML_INT_NAMEPATH_OP */
 399
 400                                 node = obj_desc->reference.node;
 401                         }
 402
 403                         /* All "References" point to a NS node */
 404
 405                         if (ACPI_GET_DESCRIPTOR_TYPE(node) !=
 406                             ACPI_DESC_TYPE_NAMED) {
 407                                 ACPI_ERROR((AE_INFO,
 408                                             "Not a namespace node %p [%s]",
 409                                             node,
 410                                             acpi_ut_get_descriptor_name(node)));
 411                                 return_ACPI_STATUS(AE_AML_INTERNAL);
 412                         }
 413
 414                         /* Get the attached object */
 415
 416                         obj_desc = acpi_ns_get_attached_object(node);
 417                         if (!obj_desc) {
 418
 419                                 /* No object, use the NS node type */
 420
 421                                 type = acpi_ns_get_type(node);
 422                                 goto exit;
 423                         }
 424
 425                         /* Check for circular references */
 426
 427                         if (obj_desc == operand) {
 428                                 return_ACPI_STATUS(AE_AML_CIRCULAR_REFERENCE);
 429                         }
 430                         break;
 431
 432                 case ACPI_REFCLASS_INDEX:
 433
 434                         /* Get the type of this reference (index into another object) */
 435
 436                         type = obj_desc->reference.target_type;
 437                         if (type != ACPI_TYPE_PACKAGE) {
 438                                 goto exit;
 439                         }
 440
 441                         /*
 442                          * The main object is a package, we want to get the type
 443                          * of the individual package element that is referenced by
 444                          * the index.
 445                          *
 446                          * This could of course in turn be another reference object.
 447                          */
 448                         obj_desc = *(obj_desc->reference.where);
 449                         if (!obj_desc) {
 450
 451                                 /* NULL package elements are allowed */
 452
 453                                 type = 0;       /* Uninitialized */
 454                                 goto exit;
 455                         }
 456                         break;
 457
 458                 case ACPI_REFCLASS_TABLE:
 459
 460                         type = ACPI_TYPE_DDB_HANDLE;
 461                         goto exit;
 462
 463                 case ACPI_REFCLASS_LOCAL:
 464                 case ACPI_REFCLASS_ARG:
 465
 466                         if (return_desc) {
 467                                 status =
 468                                     acpi_ds_method_data_get_value(obj_desc->
 469                                                                   reference.
 470                                                                   class,
 471                                                                   obj_desc->
 472                                                                   reference.
 473                                                                   value,
 474                                                                   walk_state,
 475                                                                   &obj_desc);
 476                                 if (ACPI_FAILURE(status)) {
 477                                         return_ACPI_STATUS(status);
 478                                 }
 479                                 acpi_ut_remove_reference(obj_desc);
 480                         } else {
 481                                 status =
 482                                     acpi_ds_method_data_get_node(obj_desc->
 483                                                                  reference.
 484                                                                  class,
 485                                                                  obj_desc->
 486                                                                  reference.
 487                                                                  value,
 488                                                                  walk_state,
 489                                                                  &node);
 490                                 if (ACPI_FAILURE(status)) {
 491                                         return_ACPI_STATUS(status);
 492                                 }
 493
 494                                 obj_desc = acpi_ns_get_attached_object(node);
 495                                 if (!obj_desc) {
 496                                         type = ACPI_TYPE_ANY;
 497                                         goto exit;
 498                                 }
 499                         }
 500                         break;
 501
 502                 case ACPI_REFCLASS_DEBUG:
 503
 504                         /* The Debug Object is of type "DebugObject" */
 505
 506                         type = ACPI_TYPE_DEBUG_OBJECT;
 507                         goto exit;
 508
 509                 default:
 510
 511                         ACPI_ERROR((AE_INFO,
 512                                     "Unknown Reference Class 0x%2.2X",
 513                                     obj_desc->reference.class));
 514                         return_ACPI_STATUS(AE_AML_INTERNAL);
 515                 }
 516         }
 517
 518         /*
 519          * Now we are guaranteed to have an object that has not been created
 520          * via the ref_of or Index operators.
 521          */
 522         type = obj_desc->common.type;
 523
 524 exit:
 525         /* Convert internal types to external types */
 526
 527         switch (type) {
 528         case ACPI_TYPE_LOCAL_REGION_FIELD:
 529         case ACPI_TYPE_LOCAL_BANK_FIELD:
 530         case ACPI_TYPE_LOCAL_INDEX_FIELD:
 531
 532                 type = ACPI_TYPE_FIELD_UNIT;
 533                 break;
 534
 535         case ACPI_TYPE_LOCAL_SCOPE:
 536
 537                 /* Per ACPI Specification, Scope is untyped */
 538
 539                 type = ACPI_TYPE_ANY;
 540                 break;
 541
 542         default:
 543
 544                 /* No change to Type required */
 545
 546                 break;
 547         }
 548
 549         *return_type = type;
 550         if (return_desc) {
 551                 *return_desc = obj_desc;
 552         }
 553         return_ACPI_STATUS(AE_OK);
 554 }