drivers/acpi/executer/exresolv.c

   1
   2 /******************************************************************************
   3  *
   4  * Module Name: exresolv - AML Interpreter object resolution
   5  *
   6  *****************************************************************************/
   7
   8 /*
   9  * Copyright (C) 2000 - 2006, 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         void *temp_node;
 144         union acpi_operand_object *obj_desc;
 145         u16 opcode;
 146
 147         ACPI_FUNCTION_TRACE(ex_resolve_object_to_value);
 148
 149         stack_desc = *stack_ptr;
 150
 151         /* This is an union acpi_operand_object    */
 152
 153         switch (ACPI_GET_OBJECT_TYPE(stack_desc)) {
 154         case ACPI_TYPE_LOCAL_REFERENCE:
 155
 156                 opcode = stack_desc->reference.opcode;
 157
 158                 switch (opcode) {
 159                 case AML_NAME_OP:
 160
 161                         /*
 162                          * Convert name reference to a namespace node
 163                          * Then, acpi_ex_resolve_node_to_value can be used to get the value
 164                          */
 165                         temp_node = stack_desc->reference.object;
 166
 167                         /* Delete the Reference Object */
 168
 169                         acpi_ut_remove_reference(stack_desc);
 170
 171                         /* Return the namespace node */
 172
 173                         (*stack_ptr) = temp_node;
 174                         break;
 175
 176                 case AML_LOCAL_OP:
 177                 case AML_ARG_OP:
 178
 179                         /*
 180                          * Get the local from the method's state info
 181                          * Note: this increments the local's object reference count
 182                          */
 183                         status = acpi_ds_method_data_get_value(opcode,
 184                                                                stack_desc->
 185                                                                reference.offset,
 186                                                                walk_state,
 187                                                                &obj_desc);
 188                         if (ACPI_FAILURE(status)) {
 189                                 return_ACPI_STATUS(status);
 190                         }
 191
 192                         ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
 193                                           "[Arg/Local %X] ValueObj is %p\n",
 194                                           stack_desc->reference.offset,
 195                                           obj_desc));
 196
 197                         /*
 198                          * Now we can delete the original Reference Object and
 199                          * replace it with the resolved value
 200                          */
 201                         acpi_ut_remove_reference(stack_desc);
 202                         *stack_ptr = obj_desc;
 203                         break;
 204
 205                 case AML_INDEX_OP:
 206
 207                         switch (stack_desc->reference.target_type) {
 208                         case ACPI_TYPE_BUFFER_FIELD:
 209
 210                                 /* Just return - leave the Reference on the stack */
 211                                 break;
 212
 213                         case ACPI_TYPE_PACKAGE:
 214
 215                                 obj_desc = *stack_desc->reference.where;
 216                                 if (obj_desc) {
 217                                         /*
 218                                          * Valid obj descriptor, copy pointer to return value
 219                                          * (i.e., dereference the package index)
 220                                          * Delete the ref object, increment the returned object
 221                                          */
 222                                         acpi_ut_remove_reference(stack_desc);
 223                                         acpi_ut_add_reference(obj_desc);
 224                                         *stack_ptr = obj_desc;
 225                                 } else {
 226                                         /*
 227                                          * A NULL object descriptor means an unitialized element of
 228                                          * the package, can't dereference it
 229                                          */
 230                                         ACPI_ERROR((AE_INFO,
 231                                                     "Attempt to deref an Index to NULL pkg element Idx=%p",
 232                                                     stack_desc));
 233                                         status = AE_AML_UNINITIALIZED_ELEMENT;
 234                                 }
 235                                 break;
 236
 237                         default:
 238
 239                                 /* Invalid reference object */
 240
 241                                 ACPI_ERROR((AE_INFO,
 242                                             "Unknown TargetType %X in Index/Reference obj %p",
 243                                             stack_desc->reference.target_type,
 244                                             stack_desc));
 245                                 status = AE_AML_INTERNAL;
 246                                 break;
 247                         }
 248                         break;
 249
 250                 case AML_REF_OF_OP:
 251                 case AML_DEBUG_OP:
 252                 case AML_LOAD_OP:
 253
 254                         /* Just leave the object as-is */
 255
 256                         break;
 257
 258                 case AML_INT_NAMEPATH_OP:       /* Reference to a named object */
 259
 260                         /* Get the object pointed to by the namespace node */
 261
 262                         *stack_ptr = (stack_desc->reference.node)->object;
 263                         acpi_ut_add_reference(*stack_ptr);
 264                         acpi_ut_remove_reference(stack_desc);
 265                         break;
 266
 267                 default:
 268
 269                         ACPI_ERROR((AE_INFO,
 270                                     "Unknown Reference opcode %X (%s) in %p",
 271                                     opcode, acpi_ps_get_opcode_name(opcode),
 272                                     stack_desc));
 273                         status = AE_AML_INTERNAL;
 274                         break;
 275                 }
 276                 break;
 277
 278         case ACPI_TYPE_BUFFER:
 279
 280                 status = acpi_ds_get_buffer_arguments(stack_desc);
 281                 break;
 282
 283         case ACPI_TYPE_PACKAGE:
 284
 285                 status = acpi_ds_get_package_arguments(stack_desc);
 286                 break;
 287
 288                 /* These cases may never happen here, but just in case.. */
 289
 290         case ACPI_TYPE_BUFFER_FIELD:
 291         case ACPI_TYPE_LOCAL_REGION_FIELD:
 292         case ACPI_TYPE_LOCAL_BANK_FIELD:
 293         case ACPI_TYPE_LOCAL_INDEX_FIELD:
 294
 295                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
 296                                   "FieldRead SourceDesc=%p Type=%X\n",
 297                                   stack_desc,
 298                                   ACPI_GET_OBJECT_TYPE(stack_desc)));
 299
 300                 status =
 301                     acpi_ex_read_data_from_field(walk_state, stack_desc,
 302                                                  &obj_desc);
 303                 *stack_ptr = (void *)obj_desc;
 304                 break;
 305
 306         default:
 307                 break;
 308         }
 309
 310         return_ACPI_STATUS(status);
 311 }
 312
 313 /*******************************************************************************
 314  *
 315  * FUNCTION:    acpi_ex_resolve_multiple
 316  *
 317  * PARAMETERS:  walk_state          - Current state (contains AML opcode)
 318  *              Operand             - Starting point for resolution
 319  *              return_type         - Where the object type is returned
 320  *              return_desc         - Where the resolved object is returned
 321  *
 322  * RETURN:      Status
 323  *
 324  * DESCRIPTION: Return the base object and type.  Traverse a reference list if
 325  *              necessary to get to the base object.
 326  *
 327  ******************************************************************************/
 328
 329 acpi_status
 330 acpi_ex_resolve_multiple(struct acpi_walk_state *walk_state,
 331                          union acpi_operand_object *operand,
 332                          acpi_object_type * return_type,
 333                          union acpi_operand_object **return_desc)
 334 {
 335         union acpi_operand_object *obj_desc = (void *)operand;
 336         struct acpi_namespace_node *node;
 337         acpi_object_type type;
 338         acpi_status status;
 339
 340         ACPI_FUNCTION_TRACE(acpi_ex_resolve_multiple);
 341
 342         /* Operand can be either a namespace node or an operand descriptor */
 343
 344         switch (ACPI_GET_DESCRIPTOR_TYPE(obj_desc)) {
 345         case ACPI_DESC_TYPE_OPERAND:
 346                 type = obj_desc->common.type;
 347                 break;
 348
 349         case ACPI_DESC_TYPE_NAMED:
 350                 type = ((struct acpi_namespace_node *)obj_desc)->type;
 351                 obj_desc =
 352                     acpi_ns_get_attached_object((struct acpi_namespace_node *)
 353                                                 obj_desc);
 354
 355                 /* If we had an Alias node, use the attached object for type info */
 356
 357                 if (type == ACPI_TYPE_LOCAL_ALIAS) {
 358                         type = ((struct acpi_namespace_node *)obj_desc)->type;
 359                         obj_desc =
 360                             acpi_ns_get_attached_object((struct
 361                                                          acpi_namespace_node *)
 362                                                         obj_desc);
 363                 }
 364                 break;
 365
 366         default:
 367                 return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
 368         }
 369
 370         /* If type is anything other than a reference, we are done */
 371
 372         if (type != ACPI_TYPE_LOCAL_REFERENCE) {
 373                 goto exit;
 374         }
 375
 376         /*
 377          * For reference objects created via the ref_of or Index operators,
 378          * we need to get to the base object (as per the ACPI specification
 379          * of the object_type and size_of operators). This means traversing
 380          * the list of possibly many nested references.
 381          */
 382         while (ACPI_GET_OBJECT_TYPE(obj_desc) == ACPI_TYPE_LOCAL_REFERENCE) {
 383                 switch (obj_desc->reference.opcode) {
 384                 case AML_REF_OF_OP:
 385                 case AML_INT_NAMEPATH_OP:
 386
 387                         /* Dereference the reference pointer */
 388
 389                         if (obj_desc->reference.opcode == AML_REF_OF_OP) {
 390                                 node = obj_desc->reference.object;
 391                         } else {        /* AML_INT_NAMEPATH_OP */
 392
 393                                 node = obj_desc->reference.node;
 394                         }
 395
 396                         /* All "References" point to a NS node */
 397
 398                         if (ACPI_GET_DESCRIPTOR_TYPE(node) !=
 399                             ACPI_DESC_TYPE_NAMED) {
 400                                 ACPI_ERROR((AE_INFO, "Not a NS node %p [%s]",
 401                                             node,
 402                                             acpi_ut_get_descriptor_name(node)));
 403                                 return_ACPI_STATUS(AE_AML_INTERNAL);
 404                         }
 405
 406                         /* Get the attached object */
 407
 408                         obj_desc = acpi_ns_get_attached_object(node);
 409                         if (!obj_desc) {
 410
 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                 case AML_INDEX_OP:
 425
 426                         /* Get the type of this reference (index into another object) */
 427
 428                         type = obj_desc->reference.target_type;
 429                         if (type != ACPI_TYPE_PACKAGE) {
 430                                 goto exit;
 431                         }
 432
 433                         /*
 434                          * The main object is a package, we want to get the type
 435                          * of the individual package element that is referenced by
 436                          * the index.
 437                          *
 438                          * This could of course in turn be another reference object.
 439                          */
 440                         obj_desc = *(obj_desc->reference.where);
 441                         if (!obj_desc) {
 442
 443                                 /* NULL package elements are allowed */
 444
 445                                 type = 0;       /* Uninitialized */
 446                                 goto exit;
 447                         }
 448                         break;
 449
 450                 case AML_LOCAL_OP:
 451                 case AML_ARG_OP:
 452
 453                         if (return_desc) {
 454                                 status =
 455                                     acpi_ds_method_data_get_value(obj_desc->
 456                                                                   reference.
 457                                                                   opcode,
 458                                                                   obj_desc->
 459                                                                   reference.
 460                                                                   offset,
 461                                                                   walk_state,
 462                                                                   &obj_desc);
 463                                 if (ACPI_FAILURE(status)) {
 464                                         return_ACPI_STATUS(status);
 465                                 }
 466                                 acpi_ut_remove_reference(obj_desc);
 467                         } else {
 468                                 status =
 469                                     acpi_ds_method_data_get_node(obj_desc->
 470                                                                  reference.
 471                                                                  opcode,
 472                                                                  obj_desc->
 473                                                                  reference.
 474                                                                  offset,
 475                                                                  walk_state,
 476                                                                  &node);
 477                                 if (ACPI_FAILURE(status)) {
 478                                         return_ACPI_STATUS(status);
 479                                 }
 480
 481                                 obj_desc = acpi_ns_get_attached_object(node);
 482                                 if (!obj_desc) {
 483                                         type = ACPI_TYPE_ANY;
 484                                         goto exit;
 485                                 }
 486                         }
 487                         break;
 488
 489                 case AML_DEBUG_OP:
 490
 491                         /* The Debug Object is of type "DebugObject" */
 492
 493                         type = ACPI_TYPE_DEBUG_OBJECT;
 494                         goto exit;
 495
 496                 default:
 497
 498                         ACPI_ERROR((AE_INFO,
 499                                     "Unknown Reference subtype %X",
 500                                     obj_desc->reference.opcode));
 501                         return_ACPI_STATUS(AE_AML_INTERNAL);
 502                 }
 503         }
 504
 505         /*
 506          * Now we are guaranteed to have an object that has not been created
 507          * via the ref_of or Index operators.
 508          */
 509         type = ACPI_GET_OBJECT_TYPE(obj_desc);
 510
 511       exit:
 512         /* Convert internal types to external types */
 513
 514         switch (type) {
 515         case ACPI_TYPE_LOCAL_REGION_FIELD:
 516         case ACPI_TYPE_LOCAL_BANK_FIELD:
 517         case ACPI_TYPE_LOCAL_INDEX_FIELD:
 518
 519                 type = ACPI_TYPE_FIELD_UNIT;
 520                 break;
 521
 522         case ACPI_TYPE_LOCAL_SCOPE:
 523
 524                 /* Per ACPI Specification, Scope is untyped */
 525
 526                 type = ACPI_TYPE_ANY;
 527                 break;
 528
 529         default:
 530                 /* No change to Type required */
 531                 break;
 532         }
 533
 534         *return_type = type;
 535         if (return_desc) {
 536                 *return_desc = obj_desc;
 537         }
 538         return_ACPI_STATUS(AE_OK);
 539 }