drivers/acpi/executer/exresolv.c

   1
   2 /******************************************************************************
   3  *
   4  * Module Name: exresolv - AML Interpreter object resolution
   5  *
   6  *****************************************************************************/
   7
   8 /*
   9  * Copyright (C) 2000 - 2005, R. Byron Moore
  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
  46 #include <acpi/acpi.h>
  47 #include <acpi/amlcode.h>
  48 #include <acpi/acdispat.h>
  49 #include <acpi/acinterp.h>
  50 #include <acpi/acnamesp.h>
  51 #include <acpi/acparser.h>
  52
  53
  54 #define _COMPONENT          ACPI_EXECUTER
  55          ACPI_MODULE_NAME    ("exresolv")
  56
  57 /* Local prototypes */
  58
  59 static acpi_status
  60 acpi_ex_resolve_object_to_value (
  61         union acpi_operand_object       **stack_ptr,
  62         struct acpi_walk_state          *walk_state);
  63
  64
  65 /*******************************************************************************
  66  *
  67  * FUNCTION:    acpi_ex_resolve_to_value
  68  *
  69  * PARAMETERS:  **stack_ptr         - Points to entry on obj_stack, which can
  70  *                                    be either an (union acpi_operand_object *)
  71  *                                    or an acpi_handle.
  72  *              walk_state          - Current method state
  73  *
  74  * RETURN:      Status
  75  *
  76  * DESCRIPTION: Convert Reference objects to values
  77  *
  78  ******************************************************************************/
  79
  80 acpi_status
  81 acpi_ex_resolve_to_value (
  82         union acpi_operand_object       **stack_ptr,
  83         struct acpi_walk_state          *walk_state)
  84 {
  85         acpi_status                     status;
  86
  87
  88         ACPI_FUNCTION_TRACE_PTR ("ex_resolve_to_value", stack_ptr);
  89
  90
  91         if (!stack_ptr || !*stack_ptr) {
  92                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Internal - null pointer\n"));
  93                 return_ACPI_STATUS (AE_AML_NO_OPERAND);
  94         }
  95
  96         /*
  97          * The entity pointed to by the stack_ptr can be either
  98          * 1) A valid union acpi_operand_object, or
  99          * 2) A struct acpi_namespace_node (named_obj)
 100          */
 101         if (ACPI_GET_DESCRIPTOR_TYPE (*stack_ptr) == ACPI_DESC_TYPE_OPERAND) {
 102                 status = acpi_ex_resolve_object_to_value (stack_ptr, walk_state);
 103                 if (ACPI_FAILURE (status)) {
 104                         return_ACPI_STATUS (status);
 105                 }
 106
 107                 if (!*stack_ptr) {
 108                         ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Internal - null pointer\n"));
 109                         return_ACPI_STATUS (AE_AML_NO_OPERAND);
 110                 }
 111         }
 112
 113         /*
 114          * Object on the stack may have changed if acpi_ex_resolve_object_to_value()
 115          * was called (i.e., we can't use an _else_ here.)
 116          */
 117         if (ACPI_GET_DESCRIPTOR_TYPE (*stack_ptr) == ACPI_DESC_TYPE_NAMED) {
 118                 status = acpi_ex_resolve_node_to_value (
 119                                   ACPI_CAST_INDIRECT_PTR (struct acpi_namespace_node, stack_ptr),
 120                                   walk_state);
 121                 if (ACPI_FAILURE (status)) {
 122                         return_ACPI_STATUS (status);
 123                 }
 124         }
 125
 126         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Resolved object %p\n", *stack_ptr));
 127         return_ACPI_STATUS (AE_OK);
 128 }
 129
 130
 131 /*******************************************************************************
 132  *
 133  * FUNCTION:    acpi_ex_resolve_object_to_value
 134  *
 135  * PARAMETERS:  stack_ptr       - Pointer to an internal object
 136  *              walk_state      - Current method state
 137  *
 138  * RETURN:      Status
 139  *
 140  * DESCRIPTION: Retrieve the value from an internal object. The Reference type
 141  *              uses the associated AML opcode to determine the value.
 142  *
 143  ******************************************************************************/
 144
 145 static acpi_status
 146 acpi_ex_resolve_object_to_value (
 147         union acpi_operand_object       **stack_ptr,
 148         struct acpi_walk_state          *walk_state)
 149 {
 150         acpi_status                     status = AE_OK;
 151         union acpi_operand_object       *stack_desc;
 152         void                            *temp_node;
 153         union acpi_operand_object       *obj_desc;
 154         u16                             opcode;
 155
 156
 157         ACPI_FUNCTION_TRACE ("ex_resolve_object_to_value");
 158
 159
 160         stack_desc = *stack_ptr;
 161
 162         /* This is an union acpi_operand_object    */
 163
 164         switch (ACPI_GET_OBJECT_TYPE (stack_desc)) {
 165         case ACPI_TYPE_LOCAL_REFERENCE:
 166
 167                 opcode = stack_desc->reference.opcode;
 168
 169                 switch (opcode) {
 170                 case AML_NAME_OP:
 171
 172                         /*
 173                          * Convert name reference to a namespace node
 174                          * Then, acpi_ex_resolve_node_to_value can be used to get the value
 175                          */
 176                         temp_node = stack_desc->reference.object;
 177
 178                         /* Delete the Reference Object */
 179
 180                         acpi_ut_remove_reference (stack_desc);
 181
 182                         /* Return the namespace node */
 183
 184                         (*stack_ptr) = temp_node;
 185                         break;
 186
 187
 188                 case AML_LOCAL_OP:
 189                 case AML_ARG_OP:
 190
 191                         /*
 192                          * Get the local from the method's state info
 193                          * Note: this increments the local's object reference count
 194                          */
 195                         status = acpi_ds_method_data_get_value (opcode,
 196                                           stack_desc->reference.offset, walk_state, &obj_desc);
 197                         if (ACPI_FAILURE (status)) {
 198                                 return_ACPI_STATUS (status);
 199                         }
 200
 201                         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "[Arg/Local %X] value_obj is %p\n",
 202                                 stack_desc->reference.offset, obj_desc));
 203
 204                         /*
 205                          * Now we can delete the original Reference Object and
 206                          * replace it with the resolved value
 207                          */
 208                         acpi_ut_remove_reference (stack_desc);
 209                         *stack_ptr = obj_desc;
 210                         break;
 211
 212
 213                 case AML_INDEX_OP:
 214
 215                         switch (stack_desc->reference.target_type) {
 216                         case ACPI_TYPE_BUFFER_FIELD:
 217
 218                                 /* Just return - leave the Reference on the stack */
 219                                 break;
 220
 221
 222                         case ACPI_TYPE_PACKAGE:
 223
 224                                 obj_desc = *stack_desc->reference.where;
 225                                 if (obj_desc) {
 226                                         /*
 227                                          * Valid obj descriptor, copy pointer to return value
 228                                          * (i.e., dereference the package index)
 229                                          * Delete the ref object, increment the returned object
 230                                          */
 231                                         acpi_ut_remove_reference (stack_desc);
 232                                         acpi_ut_add_reference (obj_desc);
 233                                         *stack_ptr = obj_desc;
 234                                 }
 235                                 else {
 236                                         /*
 237                                          * A NULL object descriptor means an unitialized element of
 238                                          * the package, can't dereference it
 239                                          */
 240                                         ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
 241                                                 "Attempt to deref an Index to NULL pkg element Idx=%p\n",
 242                                                 stack_desc));
 243                                         status = AE_AML_UNINITIALIZED_ELEMENT;
 244                                 }
 245                                 break;
 246
 247
 248                         default:
 249
 250                                 /* Invalid reference object */
 251
 252                                 ACPI_REPORT_ERROR ((
 253                                         "During resolve, Unknown target_type %X in Index/Reference obj %p\n",
 254                                         stack_desc->reference.target_type, stack_desc));
 255                                 status = AE_AML_INTERNAL;
 256                                 break;
 257                         }
 258                         break;
 259
 260
 261                 case AML_REF_OF_OP:
 262                 case AML_DEBUG_OP:
 263                 case AML_LOAD_OP:
 264
 265                         /* Just leave the object as-is */
 266
 267                         break;
 268
 269                 case AML_INT_NAMEPATH_OP:   /* Reference to a named object */
 270
 271                         /* Get the object pointed to by the namespace node */
 272
 273                         *stack_ptr = (stack_desc->reference.node)->object;
 274                         acpi_ut_add_reference (*stack_ptr);
 275                         acpi_ut_remove_reference (stack_desc);
 276                         break;
 277
 278                 default:
 279
 280                         ACPI_REPORT_ERROR ((
 281                                 "During resolve, Unknown Reference opcode %X (%s) in %p\n",
 282                                 opcode, acpi_ps_get_opcode_name (opcode), stack_desc));
 283                         status = AE_AML_INTERNAL;
 284                         break;
 285                 }
 286                 break;
 287
 288
 289         case ACPI_TYPE_BUFFER:
 290
 291                 status = acpi_ds_get_buffer_arguments (stack_desc);
 292                 break;
 293
 294
 295         case ACPI_TYPE_PACKAGE:
 296
 297                 status = acpi_ds_get_package_arguments (stack_desc);
 298                 break;
 299
 300
 301         /* These cases may never happen here, but just in case.. */
 302
 303         case ACPI_TYPE_BUFFER_FIELD:
 304         case ACPI_TYPE_LOCAL_REGION_FIELD:
 305         case ACPI_TYPE_LOCAL_BANK_FIELD:
 306         case ACPI_TYPE_LOCAL_INDEX_FIELD:
 307
 308                 ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "field_read source_desc=%p Type=%X\n",
 309                         stack_desc, ACPI_GET_OBJECT_TYPE (stack_desc)));
 310
 311                 status = acpi_ex_read_data_from_field (walk_state, stack_desc, &obj_desc);
 312                 *stack_ptr = (void *) obj_desc;
 313                 break;
 314
 315         default:
 316                 break;
 317         }
 318
 319         return_ACPI_STATUS (status);
 320 }
 321
 322
 323 /*******************************************************************************
 324  *
 325  * FUNCTION:    acpi_ex_resolve_multiple
 326  *
 327  * PARAMETERS:  walk_state          - Current state (contains AML opcode)
 328  *              Operand             - Starting point for resolution
 329  *              return_type         - Where the object type is returned
 330  *              return_desc         - Where the resolved object is returned
 331  *
 332  * RETURN:      Status
 333  *
 334  * DESCRIPTION: Return the base object and type.  Traverse a reference list if
 335  *              necessary to get to the base object.
 336  *
 337  ******************************************************************************/
 338
 339 acpi_status
 340 acpi_ex_resolve_multiple (
 341         struct acpi_walk_state          *walk_state,
 342         union acpi_operand_object       *operand,
 343         acpi_object_type                *return_type,
 344         union acpi_operand_object       **return_desc)
 345 {
 346         union acpi_operand_object       *obj_desc = (void *) operand;
 347         struct acpi_namespace_node      *node;
 348         acpi_object_type                type;
 349         acpi_status                     status;
 350
 351
 352         ACPI_FUNCTION_TRACE ("acpi_ex_resolve_multiple");
 353
 354
 355         /* Operand can be either a namespace node or an operand descriptor */
 356
 357         switch (ACPI_GET_DESCRIPTOR_TYPE (obj_desc)) {
 358         case ACPI_DESC_TYPE_OPERAND:
 359                 type = obj_desc->common.type;
 360                 break;
 361
 362         case ACPI_DESC_TYPE_NAMED:
 363                 type = ((struct acpi_namespace_node *) obj_desc)->type;
 364                 obj_desc = acpi_ns_get_attached_object ((struct acpi_namespace_node *) obj_desc);
 365
 366                 /* If we had an Alias node, use the attached object for type info */
 367
 368                 if (type == ACPI_TYPE_LOCAL_ALIAS) {
 369                         type = ((struct acpi_namespace_node *) obj_desc)->type;
 370                         obj_desc = acpi_ns_get_attached_object ((struct acpi_namespace_node *) obj_desc);
 371                 }
 372                 break;
 373
 374         default:
 375                 return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
 376         }
 377
 378         /* If type is anything other than a reference, we are done */
 379
 380         if (type != ACPI_TYPE_LOCAL_REFERENCE) {
 381                 goto exit;
 382         }
 383
 384         /*
 385          * For reference objects created via the ref_of or Index operators,
 386          * we need to get to the base object (as per the ACPI specification
 387          * of the object_type and size_of operators). This means traversing
 388          * the list of possibly many nested references.
 389          */
 390         while (ACPI_GET_OBJECT_TYPE (obj_desc) == ACPI_TYPE_LOCAL_REFERENCE) {
 391                 switch (obj_desc->reference.opcode) {
 392                 case AML_REF_OF_OP:
 393
 394                         /* Dereference the reference pointer */
 395
 396                         node = obj_desc->reference.object;
 397
 398                         /* All "References" point to a NS node */
 399
 400                         if (ACPI_GET_DESCRIPTOR_TYPE (node) != ACPI_DESC_TYPE_NAMED) {
 401                                 ACPI_REPORT_ERROR ((
 402                                         "acpi_ex_resolve_multiple: Not a NS node %p [%s]\n",
 403                                         node, acpi_ut_get_descriptor_name (node)));
 404                                 return_ACPI_STATUS (AE_AML_INTERNAL);
 405                         }
 406
 407                         /* Get the attached object */
 408
 409                         obj_desc = acpi_ns_get_attached_object (node);
 410                         if (!obj_desc) {
 411                                 /* No object, use the NS node type */
 412
 413                                 type = acpi_ns_get_type (node);
 414                                 goto exit;
 415                         }
 416
 417                         /* Check for circular references */
 418
 419                         if (obj_desc == operand) {
 420                                 return_ACPI_STATUS (AE_AML_CIRCULAR_REFERENCE);
 421                         }
 422                         break;
 423
 424
 425                 case AML_INDEX_OP:
 426
 427                         /* Get the type of this reference (index into another object) */
 428
 429                         type = obj_desc->reference.target_type;
 430                         if (type != ACPI_TYPE_PACKAGE) {
 431                                 goto exit;
 432                         }
 433
 434                         /*
 435                          * The main object is a package, we want to get the type
 436                          * of the individual package element that is referenced by
 437                          * the index.
 438                          *
 439                          * This could of course in turn be another reference object.
 440                          */
 441                         obj_desc = *(obj_desc->reference.where);
 442                         if (!obj_desc) {
 443                                 /* NULL package elements are allowed */
 444
 445                                 type = 0; /* Uninitialized */
 446                                 goto exit;
 447                         }
 448                         break;
 449
 450
 451                 case AML_INT_NAMEPATH_OP:
 452
 453                         /* Dereference the reference pointer */
 454
 455                         node = obj_desc->reference.node;
 456
 457                         /* All "References" point to a NS node */
 458
 459                         if (ACPI_GET_DESCRIPTOR_TYPE (node) != ACPI_DESC_TYPE_NAMED) {
 460                                 ACPI_REPORT_ERROR ((
 461                                         "acpi_ex_resolve_multiple: Not a NS node %p [%s]\n",
 462                                         node, acpi_ut_get_descriptor_name (node)));
 463                            return_ACPI_STATUS (AE_AML_INTERNAL);
 464                         }
 465
 466                         /* Get the attached object */
 467
 468                         obj_desc = acpi_ns_get_attached_object (node);
 469                         if (!obj_desc) {
 470                                 /* No object, use the NS node type */
 471
 472                                 type = acpi_ns_get_type (node);
 473                                 goto exit;
 474                         }
 475
 476                         /* Check for circular references */
 477
 478                         if (obj_desc == operand) {
 479                                 return_ACPI_STATUS (AE_AML_CIRCULAR_REFERENCE);
 480                         }
 481                         break;
 482
 483
 484                 case AML_LOCAL_OP:
 485                 case AML_ARG_OP:
 486
 487                         if (return_desc) {
 488                                 status = acpi_ds_method_data_get_value (obj_desc->reference.opcode,
 489                                                  obj_desc->reference.offset, walk_state, &obj_desc);
 490                                 if (ACPI_FAILURE (status)) {
 491                                         return_ACPI_STATUS (status);
 492                                 }
 493                                 acpi_ut_remove_reference (obj_desc);
 494                         }
 495                         else {
 496                                 status = acpi_ds_method_data_get_node (obj_desc->reference.opcode,
 497                                                  obj_desc->reference.offset, walk_state, &node);
 498                                 if (ACPI_FAILURE (status)) {
 499                                         return_ACPI_STATUS (status);
 500                                 }
 501
 502                                 obj_desc = acpi_ns_get_attached_object (node);
 503                                 if (!obj_desc) {
 504                                         type = ACPI_TYPE_ANY;
 505                                         goto exit;
 506                                 }
 507                         }
 508                         break;
 509
 510
 511                 case AML_DEBUG_OP:
 512
 513                         /* The Debug Object is of type "debug_object" */
 514
 515                         type = ACPI_TYPE_DEBUG_OBJECT;
 516                         goto exit;
 517
 518
 519                 default:
 520
 521                         ACPI_REPORT_ERROR ((
 522                                 "acpi_ex_resolve_multiple: Unknown Reference subtype %X\n",
 523                                 obj_desc->reference.opcode));
 524                         return_ACPI_STATUS (AE_AML_INTERNAL);
 525                 }
 526         }
 527
 528         /*
 529          * Now we are guaranteed to have an object that has not been created
 530          * via the ref_of or Index operators.
 531          */
 532         type = ACPI_GET_OBJECT_TYPE (obj_desc);
 533
 534
 535 exit:
 536         /* Convert internal types to external types */
 537
 538         switch (type) {
 539         case ACPI_TYPE_LOCAL_REGION_FIELD:
 540         case ACPI_TYPE_LOCAL_BANK_FIELD:
 541         case ACPI_TYPE_LOCAL_INDEX_FIELD:
 542
 543                 type = ACPI_TYPE_FIELD_UNIT;
 544                 break;
 545
 546         case ACPI_TYPE_LOCAL_SCOPE:
 547
 548                 /* Per ACPI Specification, Scope is untyped */
 549
 550                 type = ACPI_TYPE_ANY;
 551                 break;
 552
 553         default:
 554                 /* No change to Type required */
 555                 break;
 556         }
 557
 558         *return_type = type;
 559         if (return_desc) {
 560                 *return_desc = obj_desc;
 561         }
 562         return_ACPI_STATUS (AE_OK);
 563 }
 564
 565