drivers/acpi/executer/exresolv.c

   1
   2 /******************************************************************************
   3  *
   4  * Module Name: exresolv - AML Interpreter object resolution
   5  *
   6  *****************************************************************************/
   7
   8 /*
   9  * Copyright (C) 2000 - 2007, 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 #include <acpi/acpi.h>
  46 #include <acpi/amlcode.h>
  47 #include <acpi/acdispat.h>
  48 #include <acpi/acinterp.h>
  49 #include <acpi/acnamesp.h>
  50 #include <acpi/acparser.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         u16 opcode;
 145
 146         ACPI_FUNCTION_TRACE(ex_resolve_object_to_value);
 147
 148         stack_desc = *stack_ptr;
 149
 150         /* This is an union acpi_operand_object    */
 151
 152         switch (ACPI_GET_OBJECT_TYPE(stack_desc)) {
 153         case ACPI_TYPE_LOCAL_REFERENCE:
 154
 155                 opcode = stack_desc->reference.opcode;
 156
 157                 switch (opcode) {
 158                 case AML_LOCAL_OP:
 159                 case AML_ARG_OP:
 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(opcode,
 166                                                                stack_desc->
 167                                                                reference.offset,
 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.offset,
 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 AML_INDEX_OP:
 188
 189                         switch (stack_desc->reference.target_type) {
 190                         case ACPI_TYPE_BUFFER_FIELD:
 191
 192                                 /* Just return - leave the Reference on the stack */
 193                                 break;
 194
 195                         case ACPI_TYPE_PACKAGE:
 196
 197                                 obj_desc = *stack_desc->reference.where;
 198                                 if (obj_desc) {
 199                                         /*
 200                                          * Valid obj descriptor, copy pointer to return value
 201                                          * (i.e., dereference the package index)
 202                                          * Delete the ref object, increment the returned object
 203                                          */
 204                                         acpi_ut_remove_reference(stack_desc);
 205                                         acpi_ut_add_reference(obj_desc);
 206                                         *stack_ptr = obj_desc;
 207                                 } else {
 208                                         /*
 209                                          * A NULL object descriptor means an unitialized element of
 210                                          * the package, can't dereference it
 211                                          */
 212                                         ACPI_ERROR((AE_INFO,
 213                                                     "Attempt to deref an Index to NULL pkg element Idx=%p",
 214                                                     stack_desc));
 215                                         status = AE_AML_UNINITIALIZED_ELEMENT;
 216                                 }
 217                                 break;
 218
 219                         default:
 220
 221                                 /* Invalid reference object */
 222
 223                                 ACPI_ERROR((AE_INFO,
 224                                             "Unknown TargetType %X in Index/Reference obj %p",
 225                                             stack_desc->reference.target_type,
 226                                             stack_desc));
 227                                 status = AE_AML_INTERNAL;
 228                                 break;
 229                         }
 230                         break;
 231
 232                 case AML_REF_OF_OP:
 233                 case AML_DEBUG_OP:
 234                 case AML_LOAD_OP:
 235
 236                         /* Just leave the object as-is */
 237
 238                         break;
 239
 240                 case AML_INT_NAMEPATH_OP:       /* Reference to a named object */
 241
 242                         /* Dereference the name */
 243
 244                         if ((stack_desc->reference.node->type ==
 245                              ACPI_TYPE_DEVICE)
 246                             || (stack_desc->reference.node->type ==
 247                                 ACPI_TYPE_THERMAL)) {
 248
 249                                 /* These node types do not have 'real' subobjects */
 250
 251                                 *stack_ptr = (void *)stack_desc->reference.node;
 252                         } else {
 253                                 /* Get the object pointed to by the namespace node */
 254
 255                                 *stack_ptr =
 256                                     (stack_desc->reference.node)->object;
 257                                 acpi_ut_add_reference(*stack_ptr);
 258                         }
 259
 260                         acpi_ut_remove_reference(stack_desc);
 261                         break;
 262
 263                 default:
 264
 265                         ACPI_ERROR((AE_INFO,
 266                                     "Unknown Reference opcode %X (%s) in %p",
 267                                     opcode, acpi_ps_get_opcode_name(opcode),
 268                                     stack_desc));
 269                         status = AE_AML_INTERNAL;
 270                         break;
 271                 }
 272                 break;
 273
 274         case ACPI_TYPE_BUFFER:
 275
 276                 status = acpi_ds_get_buffer_arguments(stack_desc);
 277                 break;
 278
 279         case ACPI_TYPE_PACKAGE:
 280
 281                 status = acpi_ds_get_package_arguments(stack_desc);
 282                 break;
 283
 284         case ACPI_TYPE_BUFFER_FIELD:
 285         case ACPI_TYPE_LOCAL_REGION_FIELD:
 286         case ACPI_TYPE_LOCAL_BANK_FIELD:
 287         case ACPI_TYPE_LOCAL_INDEX_FIELD:
 288
 289                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
 290                                   "FieldRead SourceDesc=%p Type=%X\n",
 291                                   stack_desc,
 292                                   ACPI_GET_OBJECT_TYPE(stack_desc)));
 293
 294                 status =
 295                     acpi_ex_read_data_from_field(walk_state, stack_desc,
 296                                                  &obj_desc);
 297
 298                 /* Remove a reference to the original operand, then override */
 299
 300                 acpi_ut_remove_reference(*stack_ptr);
 301                 *stack_ptr = (void *)obj_desc;
 302                 break;
 303
 304         default:
 305                 break;
 306         }
 307
 308         return_ACPI_STATUS(status);
 309 }
 310
 311 /*******************************************************************************
 312  *
 313  * FUNCTION:    acpi_ex_resolve_multiple
 314  *
 315  * PARAMETERS:  walk_state          - Current state (contains AML opcode)
 316  *              Operand             - Starting point for resolution
 317  *              return_type         - Where the object type is returned
 318  *              return_desc         - Where the resolved object is returned
 319  *
 320  * RETURN:      Status
 321  *
 322  * DESCRIPTION: Return the base object and type.  Traverse a reference list if
 323  *              necessary to get to the base object.
 324  *
 325  ******************************************************************************/
 326
 327 acpi_status
 328 acpi_ex_resolve_multiple(struct acpi_walk_state *walk_state,
 329                          union acpi_operand_object *operand,
 330                          acpi_object_type * return_type,
 331                          union acpi_operand_object **return_desc)
 332 {
 333         union acpi_operand_object *obj_desc = (void *)operand;
 334         struct acpi_namespace_node *node;
 335         acpi_object_type type;
 336         acpi_status status;
 337
 338         ACPI_FUNCTION_TRACE(acpi_ex_resolve_multiple);
 339
 340         /* Operand can be either a namespace node or an operand descriptor */
 341
 342         switch (ACPI_GET_DESCRIPTOR_TYPE(obj_desc)) {
 343         case ACPI_DESC_TYPE_OPERAND:
 344                 type = obj_desc->common.type;
 345                 break;
 346
 347         case ACPI_DESC_TYPE_NAMED:
 348                 type = ((struct acpi_namespace_node *)obj_desc)->type;
 349                 obj_desc =
 350                     acpi_ns_get_attached_object((struct acpi_namespace_node *)
 351                                                 obj_desc);
 352
 353                 /* If we had an Alias node, use the attached object for type info */
 354
 355                 if (type == ACPI_TYPE_LOCAL_ALIAS) {
 356                         type = ((struct acpi_namespace_node *)obj_desc)->type;
 357                         obj_desc =
 358                             acpi_ns_get_attached_object((struct
 359                                                          acpi_namespace_node *)
 360                                                         obj_desc);
 361                 }
 362                 break;
 363
 364         default:
 365                 return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
 366         }
 367
 368         /* If type is anything other than a reference, we are done */
 369
 370         if (type != ACPI_TYPE_LOCAL_REFERENCE) {
 371                 goto exit;
 372         }
 373
 374         /*
 375          * For reference objects created via the ref_of or Index operators,
 376          * we need to get to the base object (as per the ACPI specification
 377          * of the object_type and size_of operators). This means traversing
 378          * the list of possibly many nested references.
 379          */
 380         while (ACPI_GET_OBJECT_TYPE(obj_desc) == ACPI_TYPE_LOCAL_REFERENCE) {
 381                 switch (obj_desc->reference.opcode) {
 382                 case AML_REF_OF_OP:
 383                 case AML_INT_NAMEPATH_OP:
 384
 385                         /* Dereference the reference pointer */
 386
 387                         if (obj_desc->reference.opcode == AML_REF_OF_OP) {
 388                                 node = obj_desc->reference.object;
 389                         } else {        /* AML_INT_NAMEPATH_OP */
 390
 391                                 node = obj_desc->reference.node;
 392                         }
 393
 394                         /* All "References" point to a NS node */
 395
 396                         if (ACPI_GET_DESCRIPTOR_TYPE(node) !=
 397                             ACPI_DESC_TYPE_NAMED) {
 398                                 ACPI_ERROR((AE_INFO, "Not a NS node %p [%s]",
 399                                             node,
 400                                             acpi_ut_get_descriptor_name(node)));
 401                                 return_ACPI_STATUS(AE_AML_INTERNAL);
 402                         }
 403
 404                         /* Get the attached object */
 405
 406                         obj_desc = acpi_ns_get_attached_object(node);
 407                         if (!obj_desc) {
 408
 409                                 /* No object, use the NS node type */
 410
 411                                 type = acpi_ns_get_type(node);
 412                                 goto exit;
 413                         }
 414
 415                         /* Check for circular references */
 416
 417                         if (obj_desc == operand) {
 418                                 return_ACPI_STATUS(AE_AML_CIRCULAR_REFERENCE);
 419                         }
 420                         break;
 421
 422                 case AML_INDEX_OP:
 423
 424                         /* Get the type of this reference (index into another object) */
 425
 426                         type = obj_desc->reference.target_type;
 427                         if (type != ACPI_TYPE_PACKAGE) {
 428                                 goto exit;
 429                         }
 430
 431                         /*
 432                          * The main object is a package, we want to get the type
 433                          * of the individual package element that is referenced by
 434                          * the index.
 435                          *
 436                          * This could of course in turn be another reference object.
 437                          */
 438                         obj_desc = *(obj_desc->reference.where);
 439                         if (!obj_desc) {
 440
 441                                 /* NULL package elements are allowed */
 442
 443                                 type = 0;       /* Uninitialized */
 444                                 goto exit;
 445                         }
 446                         break;
 447
 448                 case AML_LOCAL_OP:
 449                 case AML_ARG_OP:
 450
 451                         if (return_desc) {
 452                                 status =
 453                                     acpi_ds_method_data_get_value(obj_desc->
 454                                                                   reference.
 455                                                                   opcode,
 456                                                                   obj_desc->
 457                                                                   reference.
 458                                                                   offset,
 459                                                                   walk_state,
 460                                                                   &obj_desc);
 461                                 if (ACPI_FAILURE(status)) {
 462                                         return_ACPI_STATUS(status);
 463                                 }
 464                                 acpi_ut_remove_reference(obj_desc);
 465                         } else {
 466                                 status =
 467                                     acpi_ds_method_data_get_node(obj_desc->
 468                                                                  reference.
 469                                                                  opcode,
 470                                                                  obj_desc->
 471                                                                  reference.
 472                                                                  offset,
 473                                                                  walk_state,
 474                                                                  &node);
 475                                 if (ACPI_FAILURE(status)) {
 476                                         return_ACPI_STATUS(status);
 477                                 }
 478
 479                                 obj_desc = acpi_ns_get_attached_object(node);
 480                                 if (!obj_desc) {
 481                                         type = ACPI_TYPE_ANY;
 482                                         goto exit;
 483                                 }
 484                         }
 485                         break;
 486
 487                 case AML_DEBUG_OP:
 488
 489                         /* The Debug Object is of type "DebugObject" */
 490
 491                         type = ACPI_TYPE_DEBUG_OBJECT;
 492                         goto exit;
 493
 494                 default:
 495
 496                         ACPI_ERROR((AE_INFO,
 497                                     "Unknown Reference subtype %X",
 498                                     obj_desc->reference.opcode));
 499                         return_ACPI_STATUS(AE_AML_INTERNAL);
 500                 }
 501         }
 502
 503         /*
 504          * Now we are guaranteed to have an object that has not been created
 505          * via the ref_of or Index operators.
 506          */
 507         type = ACPI_GET_OBJECT_TYPE(obj_desc);
 508
 509       exit:
 510         /* Convert internal types to external types */
 511
 512         switch (type) {
 513         case ACPI_TYPE_LOCAL_REGION_FIELD:
 514         case ACPI_TYPE_LOCAL_BANK_FIELD:
 515         case ACPI_TYPE_LOCAL_INDEX_FIELD:
 516
 517                 type = ACPI_TYPE_FIELD_UNIT;
 518                 break;
 519
 520         case ACPI_TYPE_LOCAL_SCOPE:
 521
 522                 /* Per ACPI Specification, Scope is untyped */
 523
 524                 type = ACPI_TYPE_ANY;
 525                 break;
 526
 527         default:
 528                 /* No change to Type required */
 529                 break;
 530         }
 531
 532         *return_type = type;
 533         if (return_desc) {
 534                 *return_desc = obj_desc;
 535         }
 536         return_ACPI_STATUS(AE_OK);
 537 }