drivers/acpi/acpica/exresolv.c

   1
   2 /******************************************************************************
   3  *
   4  * Module Name: exresolv - AML Interpreter object resolution
   5  *
   6  *****************************************************************************/
   7
   8 /*
   9  * Copyright (C) 2000 - 2008, Intel Corp.
  10  * All rights reserved.
  11  *
  12  * Redistribution and use in source and binary forms, with or without
  13  * modification, are permitted provided that the following conditions
  14  * are met:
  15  * 1. Redistributions of source code must retain the above copyright
  16  *    notice, this list of conditions, and the following disclaimer,
  17  *    without modification.
  18  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  19  *    substantially similar to the "NO WARRANTY" disclaimer below
  20  *    ("Disclaimer") and any redistribution must be conditioned upon
  21  *    including a substantially similar Disclaimer requirement for further
  22  *    binary redistribution.
  23  * 3. Neither the names of the above-listed copyright holders nor the names
  24  *    of any contributors may be used to endorse or promote products derived
  25  *    from this software without specific prior written permission.
  26  *
  27  * Alternatively, this software may be distributed under the terms of the
  28  * GNU General Public License ("GPL") version 2 as published by the Free
  29  * Software Foundation.
  30  *
  31  * NO WARRANTY
  32  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  33  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  34  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
  35  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  36  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  37  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  38  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  39  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  40  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  41  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  42  * POSSIBILITY OF SUCH DAMAGES.
  43  */
  44
  45 #include <acpi/acpi.h>
  46 #include "accommon.h"
  47 #include "amlcode.h"
  48 #include "acdispat.h"
  49 #include "acinterp.h"
  50 #include "acnamesp.h"
  51
  52 #define _COMPONENT          ACPI_EXECUTER
  53 ACPI_MODULE_NAME("exresolv")
  54
  55 /* Local prototypes */
  56 static acpi_status
  57 acpi_ex_resolve_object_to_value(union acpi_operand_object **stack_ptr,
  58                                 struct acpi_walk_state *walk_state);
  59
  60 /*******************************************************************************
  61  *
  62  * FUNCTION:    acpi_ex_resolve_to_value
  63  *
  64  * PARAMETERS:  **stack_ptr         - Points to entry on obj_stack, which can
  65  *                                    be either an (union acpi_operand_object *)
  66  *                                    or an acpi_handle.
  67  *              walk_state          - Current method state
  68  *
  69  * RETURN:      Status
  70  *
  71  * DESCRIPTION: Convert Reference objects to values
  72  *
  73  ******************************************************************************/
  74
  75 acpi_status
  76 acpi_ex_resolve_to_value(union acpi_operand_object **stack_ptr,
  77                          struct acpi_walk_state *walk_state)
  78 {
  79         acpi_status status;
  80
  81         ACPI_FUNCTION_TRACE_PTR(ex_resolve_to_value, stack_ptr);
  82
  83         if (!stack_ptr || !*stack_ptr) {
  84                 ACPI_ERROR((AE_INFO, "Internal - null pointer"));
  85                 return_ACPI_STATUS(AE_AML_NO_OPERAND);
  86         }
  87
  88         /*
  89          * The entity pointed to by the stack_ptr can be either
  90          * 1) A valid union acpi_operand_object, or
  91          * 2) A struct acpi_namespace_node (named_obj)
  92          */
  93         if (ACPI_GET_DESCRIPTOR_TYPE(*stack_ptr) == ACPI_DESC_TYPE_OPERAND) {
  94                 status = acpi_ex_resolve_object_to_value(stack_ptr, walk_state);
  95                 if (ACPI_FAILURE(status)) {
  96                         return_ACPI_STATUS(status);
  97                 }
  98
  99                 if (!*stack_ptr) {
 100                         ACPI_ERROR((AE_INFO, "Internal - null pointer"));
 101                         return_ACPI_STATUS(AE_AML_NO_OPERAND);
 102                 }
 103         }
 104
 105         /*
 106          * Object on the stack may have changed if acpi_ex_resolve_object_to_value()
 107          * was called (i.e., we can't use an _else_ here.)
 108          */
 109         if (ACPI_GET_DESCRIPTOR_TYPE(*stack_ptr) == ACPI_DESC_TYPE_NAMED) {
 110                 status =
 111                     acpi_ex_resolve_node_to_value(ACPI_CAST_INDIRECT_PTR
 112                                                   (struct acpi_namespace_node,
 113                                                    stack_ptr), walk_state);
 114                 if (ACPI_FAILURE(status)) {
 115                         return_ACPI_STATUS(status);
 116                 }
 117         }
 118
 119         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Resolved object %p\n", *stack_ptr));
 120         return_ACPI_STATUS(AE_OK);
 121 }
 122
 123 /*******************************************************************************
 124  *
 125  * FUNCTION:    acpi_ex_resolve_object_to_value
 126  *
 127  * PARAMETERS:  stack_ptr       - Pointer to an internal object
 128  *              walk_state      - Current method state
 129  *
 130  * RETURN:      Status
 131  *
 132  * DESCRIPTION: Retrieve the value from an internal object. The Reference type
 133  *              uses the associated AML opcode to determine the value.
 134  *
 135  ******************************************************************************/
 136
 137 static acpi_status
 138 acpi_ex_resolve_object_to_value(union acpi_operand_object **stack_ptr,
 139                                 struct acpi_walk_state *walk_state)
 140 {
 141         acpi_status status = AE_OK;
 142         union acpi_operand_object *stack_desc;
 143         union acpi_operand_object *obj_desc = NULL;
 144         u8 ref_type;
 145
 146         ACPI_FUNCTION_TRACE(ex_resolve_object_to_value);
 147
 148         stack_desc = *stack_ptr;
 149
 150         /* This is a union acpi_operand_object    */
 151
 152         switch (ACPI_GET_OBJECT_TYPE(stack_desc)) {
 153         case ACPI_TYPE_LOCAL_REFERENCE:
 154
 155                 ref_type = stack_desc->reference.class;
 156
 157                 switch (ref_type) {
 158                 case ACPI_REFCLASS_LOCAL:
 159                 case ACPI_REFCLASS_ARG:
 160
 161                         /*
 162                          * Get the local from the method's state info
 163                          * Note: this increments the local's object reference count
 164                          */
 165                         status = acpi_ds_method_data_get_value(ref_type,
 166                                                                stack_desc->
 167                                                                reference.value,
 168                                                                walk_state,
 169                                                                &obj_desc);
 170                         if (ACPI_FAILURE(status)) {
 171                                 return_ACPI_STATUS(status);
 172                         }
 173
 174                         ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
 175                                           "[Arg/Local %X] ValueObj is %p\n",
 176                                           stack_desc->reference.value,
 177                                           obj_desc));
 178
 179                         /*
 180                          * Now we can delete the original Reference Object and
 181                          * replace it with the resolved value
 182                          */
 183                         acpi_ut_remove_reference(stack_desc);
 184                         *stack_ptr = obj_desc;
 185                         break;
 186
 187                 case ACPI_REFCLASS_INDEX:
 188
 189                         switch (stack_desc->reference.target_type) {
 190                         case ACPI_TYPE_BUFFER_FIELD:
 191
 192                                 /* Just return - do not dereference */
 193                                 break;
 194
 195                         case ACPI_TYPE_PACKAGE:
 196
 197                                 /* If method call or copy_object - do not dereference */
 198
 199                                 if ((walk_state->opcode ==
 200                                      AML_INT_METHODCALL_OP)
 201                                     || (walk_state->opcode == AML_COPY_OP)) {
 202                                         break;
 203                                 }
 204
 205                                 /* Otherwise, dereference the package_index to a package element */
 206
 207                                 obj_desc = *stack_desc->reference.where;
 208                                 if (obj_desc) {
 209                                         /*
 210                                          * Valid object descriptor, copy pointer to return value
 211                                          * (i.e., dereference the package index)
 212                                          * Delete the ref object, increment the returned object
 213                                          */
 214                                         acpi_ut_remove_reference(stack_desc);
 215                                         acpi_ut_add_reference(obj_desc);
 216                                         *stack_ptr = obj_desc;
 217                                 } else {
 218                                         /*
 219                                          * A NULL object descriptor means an uninitialized element of
 220                                          * the package, can't dereference it
 221                                          */
 222                                         ACPI_ERROR((AE_INFO,
 223                                                     "Attempt to dereference an Index to NULL package element Idx=%p",
 224                                                     stack_desc));
 225                                         status = AE_AML_UNINITIALIZED_ELEMENT;
 226                                 }
 227                                 break;
 228
 229                         default:
 230
 231                                 /* Invalid reference object */
 232
 233                                 ACPI_ERROR((AE_INFO,
 234                                             "Unknown TargetType %X in Index/Reference object %p",
 235                                             stack_desc->reference.target_type,
 236                                             stack_desc));
 237                                 status = AE_AML_INTERNAL;
 238                                 break;
 239                         }
 240                         break;
 241
 242                 case ACPI_REFCLASS_REFOF:
 243                 case ACPI_REFCLASS_DEBUG:
 244                 case ACPI_REFCLASS_TABLE:
 245
 246                         /* Just leave the object as-is, do not dereference */
 247
 248                         break;
 249
 250                 case ACPI_REFCLASS_NAME:        /* Reference to a named object */
 251
 252                         /* Dereference the name */
 253
 254                         if ((stack_desc->reference.node->type ==
 255                              ACPI_TYPE_DEVICE)
 256                             || (stack_desc->reference.node->type ==
 257                                 ACPI_TYPE_THERMAL)) {
 258
 259                                 /* These node types do not have 'real' subobjects */
 260
 261                                 *stack_ptr = (void *)stack_desc->reference.node;
 262                         } else {
 263                                 /* Get the object pointed to by the namespace node */
 264
 265                                 *stack_ptr =
 266                                     (stack_desc->reference.node)->object;
 267                                 acpi_ut_add_reference(*stack_ptr);
 268                         }
 269
 270                         acpi_ut_remove_reference(stack_desc);
 271                         break;
 272
 273                 default:
 274
 275                         ACPI_ERROR((AE_INFO,
 276                                     "Unknown Reference type %X in %p", ref_type,
 277                                     stack_desc));
 278                         status = AE_AML_INTERNAL;
 279                         break;
 280                 }
 281                 break;
 282
 283         case ACPI_TYPE_BUFFER:
 284
 285                 status = acpi_ds_get_buffer_arguments(stack_desc);
 286                 break;
 287
 288         case ACPI_TYPE_PACKAGE:
 289
 290                 status = acpi_ds_get_package_arguments(stack_desc);
 291                 break;
 292
 293         case ACPI_TYPE_BUFFER_FIELD:
 294         case ACPI_TYPE_LOCAL_REGION_FIELD:
 295         case ACPI_TYPE_LOCAL_BANK_FIELD:
 296         case ACPI_TYPE_LOCAL_INDEX_FIELD:
 297
 298                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
 299                                   "FieldRead SourceDesc=%p Type=%X\n",
 300                                   stack_desc,
 301                                   ACPI_GET_OBJECT_TYPE(stack_desc)));
 302
 303                 status =
 304                     acpi_ex_read_data_from_field(walk_state, stack_desc,
 305                                                  &obj_desc);
 306
 307                 /* Remove a reference to the original operand, then override */
 308
 309                 acpi_ut_remove_reference(*stack_ptr);
 310                 *stack_ptr = (void *)obj_desc;
 311                 break;
 312
 313         default:
 314                 break;
 315         }
 316
 317         return_ACPI_STATUS(status);
 318 }
 319
 320 /*******************************************************************************
 321  *
 322  * FUNCTION:    acpi_ex_resolve_multiple
 323  *
 324  * PARAMETERS:  walk_state          - Current state (contains AML opcode)
 325  *              Operand             - Starting point for resolution
 326  *              return_type         - Where the object type is returned
 327  *              return_desc         - Where the resolved object is returned
 328  *
 329  * RETURN:      Status
 330  *
 331  * DESCRIPTION: Return the base object and type.  Traverse a reference list if
 332  *              necessary to get to the base object.
 333  *
 334  ******************************************************************************/
 335
 336 acpi_status
 337 acpi_ex_resolve_multiple(struct acpi_walk_state *walk_state,
 338                          union acpi_operand_object *operand,
 339                          acpi_object_type * return_type,
 340                          union acpi_operand_object **return_desc)
 341 {
 342         union acpi_operand_object *obj_desc = (void *)operand;
 343         struct acpi_namespace_node *node;
 344         acpi_object_type type;
 345         acpi_status status;
 346
 347         ACPI_FUNCTION_TRACE(acpi_ex_resolve_multiple);
 348
 349         /* Operand can be either a namespace node or an operand descriptor */
 350
 351         switch (ACPI_GET_DESCRIPTOR_TYPE(obj_desc)) {
 352         case ACPI_DESC_TYPE_OPERAND:
 353                 type = obj_desc->common.type;
 354                 break;
 355
 356         case ACPI_DESC_TYPE_NAMED:
 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 (ACPI_GET_OBJECT_TYPE(obj_desc) == 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, "Not a NS node %p [%s]",
 408                                             node,
 409                                             acpi_ut_get_descriptor_name(node)));
 410                                 return_ACPI_STATUS(AE_AML_INTERNAL);
 411                         }
 412
 413                         /* Get the attached object */
 414
 415                         obj_desc = acpi_ns_get_attached_object(node);
 416                         if (!obj_desc) {
 417
 418                                 /* No object, use the NS node type */
 419
 420                                 type = acpi_ns_get_type(node);
 421                                 goto exit;
 422                         }
 423
 424                         /* Check for circular references */
 425
 426                         if (obj_desc == operand) {
 427                                 return_ACPI_STATUS(AE_AML_CIRCULAR_REFERENCE);
 428                         }
 429                         break;
 430
 431                 case ACPI_REFCLASS_INDEX:
 432
 433                         /* Get the type of this reference (index into another object) */
 434
 435                         type = obj_desc->reference.target_type;
 436                         if (type != ACPI_TYPE_PACKAGE) {
 437                                 goto exit;
 438                         }
 439
 440                         /*
 441                          * The main object is a package, we want to get the type
 442                          * of the individual package element that is referenced by
 443                          * the index.
 444                          *
 445                          * This could of course in turn be another reference object.
 446                          */
 447                         obj_desc = *(obj_desc->reference.where);
 448                         if (!obj_desc) {
 449
 450                                 /* NULL package elements are allowed */
 451
 452                                 type = 0;       /* Uninitialized */
 453                                 goto exit;
 454                         }
 455                         break;
 456
 457                 case ACPI_REFCLASS_TABLE:
 458
 459                         type = ACPI_TYPE_DDB_HANDLE;
 460                         goto exit;
 461
 462                 case ACPI_REFCLASS_LOCAL:
 463                 case ACPI_REFCLASS_ARG:
 464
 465                         if (return_desc) {
 466                                 status =
 467                                     acpi_ds_method_data_get_value(obj_desc->
 468                                                                   reference.
 469                                                                   class,
 470                                                                   obj_desc->
 471                                                                   reference.
 472                                                                   value,
 473                                                                   walk_state,
 474                                                                   &obj_desc);
 475                                 if (ACPI_FAILURE(status)) {
 476                                         return_ACPI_STATUS(status);
 477                                 }
 478                                 acpi_ut_remove_reference(obj_desc);
 479                         } else {
 480                                 status =
 481                                     acpi_ds_method_data_get_node(obj_desc->
 482                                                                  reference.
 483                                                                  class,
 484                                                                  obj_desc->
 485                                                                  reference.
 486                                                                  value,
 487                                                                  walk_state,
 488                                                                  &node);
 489                                 if (ACPI_FAILURE(status)) {
 490                                         return_ACPI_STATUS(status);
 491                                 }
 492
 493                                 obj_desc = acpi_ns_get_attached_object(node);
 494                                 if (!obj_desc) {
 495                                         type = ACPI_TYPE_ANY;
 496                                         goto exit;
 497                                 }
 498                         }
 499                         break;
 500
 501                 case ACPI_REFCLASS_DEBUG:
 502
 503                         /* The Debug Object is of type "DebugObject" */
 504
 505                         type = ACPI_TYPE_DEBUG_OBJECT;
 506                         goto exit;
 507
 508                 default:
 509
 510                         ACPI_ERROR((AE_INFO,
 511                                     "Unknown Reference Class %2.2X",
 512                                     obj_desc->reference.class));
 513                         return_ACPI_STATUS(AE_AML_INTERNAL);
 514                 }
 515         }
 516
 517         /*
 518          * Now we are guaranteed to have an object that has not been created
 519          * via the ref_of or Index operators.
 520          */
 521         type = ACPI_GET_OBJECT_TYPE(obj_desc);
 522
 523       exit:
 524         /* Convert internal types to external types */
 525
 526         switch (type) {
 527         case ACPI_TYPE_LOCAL_REGION_FIELD:
 528         case ACPI_TYPE_LOCAL_BANK_FIELD:
 529         case ACPI_TYPE_LOCAL_INDEX_FIELD:
 530
 531                 type = ACPI_TYPE_FIELD_UNIT;
 532                 break;
 533
 534         case ACPI_TYPE_LOCAL_SCOPE:
 535
 536                 /* Per ACPI Specification, Scope is untyped */
 537
 538                 type = ACPI_TYPE_ANY;
 539                 break;
 540
 541         default:
 542                 /* No change to Type required */
 543                 break;
 544         }
 545
 546         *return_type = type;
 547         if (return_desc) {
 548                 *return_desc = obj_desc;
 549         }
 550         return_ACPI_STATUS(AE_OK);
 551 }