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