drivers/acpi/acpica/exresolv.c

   1 /******************************************************************************
   2  *
   3  * Module Name: exresolv - AML Interpreter object resolution
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2012, 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                         /*
 161                          * Get the local from the method's state info
 162                          * Note: this increments the local's object reference count
 163                          */
 164                         status = acpi_ds_method_data_get_value(ref_type,
 165                                                                stack_desc->
 166                                                                reference.value,
 167                                                                walk_state,
 168                                                                &obj_desc);
 169                         if (ACPI_FAILURE(status)) {
 170                                 return_ACPI_STATUS(status);
 171                         }
 172
 173                         ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
 174                                           "[Arg/Local %X] ValueObj is %p\n",
 175                                           stack_desc->reference.value,
 176                                           obj_desc));
 177
 178                         /*
 179                          * Now we can delete the original Reference Object and
 180                          * replace it with the resolved value
 181                          */
 182                         acpi_ut_remove_reference(stack_desc);
 183                         *stack_ptr = obj_desc;
 184                         break;
 185
 186                 case ACPI_REFCLASS_INDEX:
 187
 188                         switch (stack_desc->reference.target_type) {
 189                         case ACPI_TYPE_BUFFER_FIELD:
 190
 191                                 /* Just return - do not dereference */
 192                                 break;
 193
 194                         case ACPI_TYPE_PACKAGE:
 195
 196                                 /* If method call or copy_object - do not dereference */
 197
 198                                 if ((walk_state->opcode ==
 199                                      AML_INT_METHODCALL_OP)
 200                                     || (walk_state->opcode == AML_COPY_OP)) {
 201                                         break;
 202                                 }
 203
 204                                 /* Otherwise, dereference the package_index to a package element */
 205
 206                                 obj_desc = *stack_desc->reference.where;
 207                                 if (obj_desc) {
 208                                         /*
 209                                          * Valid object descriptor, copy pointer to return value
 210                                          * (i.e., dereference the package index)
 211                                          * Delete the ref object, increment the returned object
 212                                          */
 213                                         acpi_ut_remove_reference(stack_desc);
 214                                         acpi_ut_add_reference(obj_desc);
 215                                         *stack_ptr = obj_desc;
 216                                 } else {
 217                                         /*
 218                                          * A NULL object descriptor means an uninitialized element of
 219                                          * the package, can't dereference it
 220                                          */
 221                                         ACPI_ERROR((AE_INFO,
 222                                                     "Attempt to dereference an Index to NULL package element Idx=%p",
 223                                                     stack_desc));
 224                                         status = AE_AML_UNINITIALIZED_ELEMENT;
 225                                 }
 226                                 break;
 227
 228                         default:
 229
 230                                 /* Invalid reference object */
 231
 232                                 ACPI_ERROR((AE_INFO,
 233                                             "Unknown TargetType 0x%X in Index/Reference object %p",
 234                                             stack_desc->reference.target_type,
 235                                             stack_desc));
 236                                 status = AE_AML_INTERNAL;
 237                                 break;
 238                         }
 239                         break;
 240
 241                 case ACPI_REFCLASS_REFOF:
 242                 case ACPI_REFCLASS_DEBUG:
 243                 case ACPI_REFCLASS_TABLE:
 244
 245                         /* Just leave the object as-is, do not dereference */
 246
 247                         break;
 248
 249                 case ACPI_REFCLASS_NAME:        /* Reference to a named object */
 250
 251                         /* Dereference the name */
 252
 253                         if ((stack_desc->reference.node->type ==
 254                              ACPI_TYPE_DEVICE)
 255                             || (stack_desc->reference.node->type ==
 256                                 ACPI_TYPE_THERMAL)) {
 257
 258                                 /* These node types do not have 'real' subobjects */
 259
 260                                 *stack_ptr = (void *)stack_desc->reference.node;
 261                         } else {
 262                                 /* Get the object pointed to by the namespace node */
 263
 264                                 *stack_ptr =
 265                                     (stack_desc->reference.node)->object;
 266                                 acpi_ut_add_reference(*stack_ptr);
 267                         }
 268
 269                         acpi_ut_remove_reference(stack_desc);
 270                         break;
 271
 272                 default:
 273
 274                         ACPI_ERROR((AE_INFO,
 275                                     "Unknown Reference type 0x%X in %p",
 276                                     ref_type, stack_desc));
 277                         status = AE_AML_INTERNAL;
 278                         break;
 279                 }
 280                 break;
 281
 282         case ACPI_TYPE_BUFFER:
 283
 284                 status = acpi_ds_get_buffer_arguments(stack_desc);
 285                 break;
 286
 287         case ACPI_TYPE_PACKAGE:
 288
 289                 status = acpi_ds_get_package_arguments(stack_desc);
 290                 break;
 291
 292         case ACPI_TYPE_BUFFER_FIELD:
 293         case ACPI_TYPE_LOCAL_REGION_FIELD:
 294         case ACPI_TYPE_LOCAL_BANK_FIELD:
 295         case ACPI_TYPE_LOCAL_INDEX_FIELD:
 296
 297                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
 298                                   "FieldRead SourceDesc=%p Type=%X\n",
 299                                   stack_desc, stack_desc->common.type));
 300
 301                 status =
 302                     acpi_ex_read_data_from_field(walk_state, stack_desc,
 303                                                  &obj_desc);
 304
 305                 /* Remove a reference to the original operand, then override */
 306
 307                 acpi_ut_remove_reference(*stack_ptr);
 308                 *stack_ptr = (void *)obj_desc;
 309                 break;
 310
 311         default:
 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                 type = obj_desc->common.type;
 352                 break;
 353
 354         case ACPI_DESC_TYPE_NAMED:
 355                 type = ((struct acpi_namespace_node *)obj_desc)->type;
 356                 obj_desc =
 357                     acpi_ns_get_attached_object((struct acpi_namespace_node *)
 358                                                 obj_desc);
 359
 360                 /* If we had an Alias node, use the attached object for type info */
 361
 362                 if (type == ACPI_TYPE_LOCAL_ALIAS) {
 363                         type = ((struct acpi_namespace_node *)obj_desc)->type;
 364                         obj_desc =
 365                             acpi_ns_get_attached_object((struct
 366                                                          acpi_namespace_node *)
 367                                                         obj_desc);
 368                 }
 369                 break;
 370
 371         default:
 372                 return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
 373         }
 374
 375         /* If type is anything other than a reference, we are done */
 376
 377         if (type != ACPI_TYPE_LOCAL_REFERENCE) {
 378                 goto exit;
 379         }
 380
 381         /*
 382          * For reference objects created via the ref_of, Index, or Load/load_table
 383          * operators, we need to get to the base object (as per the ACPI
 384          * specification of the object_type and size_of operators). This means
 385          * traversing the list of possibly many nested references.
 386          */
 387         while (obj_desc->common.type == ACPI_TYPE_LOCAL_REFERENCE) {
 388                 switch (obj_desc->reference.class) {
 389                 case ACPI_REFCLASS_REFOF:
 390                 case ACPI_REFCLASS_NAME:
 391
 392                         /* Dereference the reference pointer */
 393
 394                         if (obj_desc->reference.class == ACPI_REFCLASS_REFOF) {
 395                                 node = obj_desc->reference.object;
 396                         } else {        /* AML_INT_NAMEPATH_OP */
 397
 398                                 node = obj_desc->reference.node;
 399                         }
 400
 401                         /* All "References" point to a NS node */
 402
 403                         if (ACPI_GET_DESCRIPTOR_TYPE(node) !=
 404                             ACPI_DESC_TYPE_NAMED) {
 405                                 ACPI_ERROR((AE_INFO,
 406                                             "Not a namespace node %p [%s]",
 407                                             node,
 408                                             acpi_ut_get_descriptor_name(node)));
 409                                 return_ACPI_STATUS(AE_AML_INTERNAL);
 410                         }
 411
 412                         /* Get the attached object */
 413
 414                         obj_desc = acpi_ns_get_attached_object(node);
 415                         if (!obj_desc) {
 416
 417                                 /* No object, use the NS node type */
 418
 419                                 type = acpi_ns_get_type(node);
 420                                 goto exit;
 421                         }
 422
 423                         /* Check for circular references */
 424
 425                         if (obj_desc == operand) {
 426                                 return_ACPI_STATUS(AE_AML_CIRCULAR_REFERENCE);
 427                         }
 428                         break;
 429
 430                 case ACPI_REFCLASS_INDEX:
 431
 432                         /* Get the type of this reference (index into another object) */
 433
 434                         type = obj_desc->reference.target_type;
 435                         if (type != ACPI_TYPE_PACKAGE) {
 436                                 goto exit;
 437                         }
 438
 439                         /*
 440                          * The main object is a package, we want to get the type
 441                          * of the individual package element that is referenced by
 442                          * the index.
 443                          *
 444                          * This could of course in turn be another reference object.
 445                          */
 446                         obj_desc = *(obj_desc->reference.where);
 447                         if (!obj_desc) {
 448
 449                                 /* NULL package elements are allowed */
 450
 451                                 type = 0;       /* Uninitialized */
 452                                 goto exit;
 453                         }
 454                         break;
 455
 456                 case ACPI_REFCLASS_TABLE:
 457
 458                         type = ACPI_TYPE_DDB_HANDLE;
 459                         goto exit;
 460
 461                 case ACPI_REFCLASS_LOCAL:
 462                 case ACPI_REFCLASS_ARG:
 463
 464                         if (return_desc) {
 465                                 status =
 466                                     acpi_ds_method_data_get_value(obj_desc->
 467                                                                   reference.
 468                                                                   class,
 469                                                                   obj_desc->
 470                                                                   reference.
 471                                                                   value,
 472                                                                   walk_state,
 473                                                                   &obj_desc);
 474                                 if (ACPI_FAILURE(status)) {
 475                                         return_ACPI_STATUS(status);
 476                                 }
 477                                 acpi_ut_remove_reference(obj_desc);
 478                         } else {
 479                                 status =
 480                                     acpi_ds_method_data_get_node(obj_desc->
 481                                                                  reference.
 482                                                                  class,
 483                                                                  obj_desc->
 484                                                                  reference.
 485                                                                  value,
 486                                                                  walk_state,
 487                                                                  &node);
 488                                 if (ACPI_FAILURE(status)) {
 489                                         return_ACPI_STATUS(status);
 490                                 }
 491
 492                                 obj_desc = acpi_ns_get_attached_object(node);
 493                                 if (!obj_desc) {
 494                                         type = ACPI_TYPE_ANY;
 495                                         goto exit;
 496                                 }
 497                         }
 498                         break;
 499
 500                 case ACPI_REFCLASS_DEBUG:
 501
 502                         /* The Debug Object is of type "DebugObject" */
 503
 504                         type = ACPI_TYPE_DEBUG_OBJECT;
 505                         goto exit;
 506
 507                 default:
 508
 509                         ACPI_ERROR((AE_INFO,
 510                                     "Unknown Reference Class 0x%2.2X",
 511                                     obj_desc->reference.class));
 512                         return_ACPI_STATUS(AE_AML_INTERNAL);
 513                 }
 514         }
 515
 516         /*
 517          * Now we are guaranteed to have an object that has not been created
 518          * via the ref_of or Index operators.
 519          */
 520         type = obj_desc->common.type;
 521
 522       exit:
 523         /* Convert internal types to external types */
 524
 525         switch (type) {
 526         case ACPI_TYPE_LOCAL_REGION_FIELD:
 527         case ACPI_TYPE_LOCAL_BANK_FIELD:
 528         case ACPI_TYPE_LOCAL_INDEX_FIELD:
 529
 530                 type = ACPI_TYPE_FIELD_UNIT;
 531                 break;
 532
 533         case ACPI_TYPE_LOCAL_SCOPE:
 534
 535                 /* Per ACPI Specification, Scope is untyped */
 536
 537                 type = ACPI_TYPE_ANY;
 538                 break;
 539
 540         default:
 541                 /* No change to Type required */
 542                 break;
 543         }
 544
 545         *return_type = type;
 546         if (return_desc) {
 547                 *return_desc = obj_desc;
 548         }
 549         return_ACPI_STATUS(AE_OK);
 550 }