drivers/acpi/executer/exresolv.c

   1
   2 /******************************************************************************
   3  *
   4  * Module Name: exresolv - AML Interpreter object resolution
   5  *
   6  *****************************************************************************/
   7
   8 /*
   9  * Copyright (C) 2000 - 2004, 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
  58 /*******************************************************************************
  59  *
  60  * FUNCTION:    acpi_ex_resolve_to_value
  61  *
  62  * PARAMETERS:  **stack_ptr         - Points to entry on obj_stack, which can
  63  *                                    be either an (union acpi_operand_object *)
  64  *                                    or an acpi_handle.
  65  *              walk_state          - Current method state
  66  *
  67  * RETURN:      Status
  68  *
  69  * DESCRIPTION: Convert Reference objects to values
  70  *
  71  ******************************************************************************/
  72
  73 acpi_status
  74 acpi_ex_resolve_to_value (
  75         union acpi_operand_object       **stack_ptr,
  76         struct acpi_walk_state          *walk_state)
  77 {
  78         acpi_status                     status;
  79
  80
  81         ACPI_FUNCTION_TRACE_PTR ("ex_resolve_to_value", stack_ptr);
  82
  83
  84         if (!stack_ptr || !*stack_ptr) {
  85                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Internal - null pointer\n"));
  86                 return_ACPI_STATUS (AE_AML_NO_OPERAND);
  87         }
  88
  89         /*
  90          * The entity pointed to by the stack_ptr can be either
  91          * 1) A valid union acpi_operand_object, or
  92          * 2) A struct acpi_namespace_node (named_obj)
  93          */
  94         if (ACPI_GET_DESCRIPTOR_TYPE (*stack_ptr) == ACPI_DESC_TYPE_OPERAND) {
  95                 status = acpi_ex_resolve_object_to_value (stack_ptr, walk_state);
  96                 if (ACPI_FAILURE (status)) {
  97                         return_ACPI_STATUS (status);
  98                 }
  99         }
 100
 101         /*
 102          * Object on the stack may have changed if acpi_ex_resolve_object_to_value()
 103          * was called (i.e., we can't use an _else_ here.)
 104          */
 105         if (ACPI_GET_DESCRIPTOR_TYPE (*stack_ptr) == ACPI_DESC_TYPE_NAMED) {
 106                 status = acpi_ex_resolve_node_to_value (
 107                                   ACPI_CAST_INDIRECT_PTR (struct acpi_namespace_node, stack_ptr),
 108                                   walk_state);
 109                 if (ACPI_FAILURE (status)) {
 110                         return_ACPI_STATUS (status);
 111                 }
 112         }
 113
 114         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Resolved object %p\n", *stack_ptr));
 115         return_ACPI_STATUS (AE_OK);
 116 }
 117
 118
 119 /*******************************************************************************
 120  *
 121  * FUNCTION:    acpi_ex_resolve_object_to_value
 122  *
 123  * PARAMETERS:  stack_ptr       - Pointer to a stack location that contains a
 124  *                                ptr to an internal object.
 125  *              walk_state      - Current method state
 126  *
 127  * RETURN:      Status
 128  *
 129  * DESCRIPTION: Retrieve the value from an internal object.  The Reference type
 130  *              uses the associated AML opcode to determine the value.
 131  *
 132  ******************************************************************************/
 133
 134 acpi_status
 135 acpi_ex_resolve_object_to_value (
 136         union acpi_operand_object       **stack_ptr,
 137         struct acpi_walk_state          *walk_state)
 138 {
 139         acpi_status                     status = AE_OK;
 140         union acpi_operand_object       *stack_desc;
 141         void                            *temp_node;
 142         union acpi_operand_object       *obj_desc;
 143         u16                             opcode;
 144
 145
 146         ACPI_FUNCTION_TRACE ("ex_resolve_object_to_value");
 147
 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 indirect name ptr to a direct name ptr.
 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                         /* Put direct name pointer onto stack and exit */
 172
 173                         (*stack_ptr) = temp_node;
 174                         break;
 175
 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->reference.offset, walk_state, &obj_desc);
 186                         if (ACPI_FAILURE (status)) {
 187                                 return_ACPI_STATUS (status);
 188                         }
 189
 190                         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "[Arg/Local %X] value_obj is %p\n",
 191                                 stack_desc->reference.offset, obj_desc));
 192
 193                         /*
 194                          * Now we can delete the original Reference Object and
 195                          * replace it with the resolved value
 196                          */
 197                         acpi_ut_remove_reference (stack_desc);
 198                         *stack_ptr = obj_desc;
 199                         break;
 200
 201
 202                 case AML_INDEX_OP:
 203
 204                         switch (stack_desc->reference.target_type) {
 205                         case ACPI_TYPE_BUFFER_FIELD:
 206
 207                                 /* Just return - leave the Reference on the stack */
 208                                 break;
 209
 210
 211                         case ACPI_TYPE_PACKAGE:
 212
 213                                 obj_desc = *stack_desc->reference.where;
 214                                 if (obj_desc) {
 215                                         /*
 216                                          * Valid obj descriptor, copy pointer to return value
 217                                          * (i.e., dereference the package index)
 218                                          * Delete the ref object, increment the returned object
 219                                          */
 220                                         acpi_ut_remove_reference (stack_desc);
 221                                         acpi_ut_add_reference (obj_desc);
 222                                         *stack_ptr = obj_desc;
 223                                 }
 224                                 else {
 225                                         /*
 226                                          * A NULL object descriptor means an unitialized element of
 227                                          * the package, can't dereference it
 228                                          */
 229                                         ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
 230                                                 "Attempt to deref an Index to NULL pkg element Idx=%p\n",
 231                                                 stack_desc));
 232                                         status = AE_AML_UNINITIALIZED_ELEMENT;
 233                                 }
 234                                 break;
 235
 236
 237                         default:
 238
 239                                 /* Invalid reference object */
 240
 241                                 ACPI_REPORT_ERROR ((
 242                                         "During resolve, Unknown target_type %X in Index/Reference obj %p\n",
 243                                         stack_desc->reference.target_type, stack_desc));
 244                                 status = AE_AML_INTERNAL;
 245                                 break;
 246                         }
 247                         break;
 248
 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
 259                 default:
 260
 261                         ACPI_REPORT_ERROR (("During resolve, Unknown Reference opcode %X (%s) in %p\n",
 262                                 opcode, acpi_ps_get_opcode_name (opcode), stack_desc));
 263                         status = AE_AML_INTERNAL;
 264                         break;
 265                 }
 266                 break;
 267
 268
 269         case ACPI_TYPE_BUFFER:
 270
 271                 status = acpi_ds_get_buffer_arguments (stack_desc);
 272                 break;
 273
 274
 275         case ACPI_TYPE_PACKAGE:
 276
 277                 status = acpi_ds_get_package_arguments (stack_desc);
 278                 break;
 279
 280
 281         /*
 282          * These cases may never happen here, but just in case..
 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, "field_read source_desc=%p Type=%X\n",
 290                         stack_desc, ACPI_GET_OBJECT_TYPE (stack_desc)));
 291
 292                 status = acpi_ex_read_data_from_field (walk_state, stack_desc, &obj_desc);
 293                 *stack_ptr = (void *) obj_desc;
 294                 break;
 295
 296         default:
 297                 break;
 298         }
 299
 300         return_ACPI_STATUS (status);
 301 }
 302
 303
 304 /*******************************************************************************
 305  *
 306  * FUNCTION:    acpi_ex_resolve_multiple
 307  *
 308  * PARAMETERS:  walk_state          - Current state (contains AML opcode)
 309  *              Operand             - Starting point for resolution
 310  *              return_type         - Where the object type is returned
 311  *              return_desc         - Where the resolved object is returned
 312  *
 313  * RETURN:      Status
 314  *
 315  * DESCRIPTION: Return the base object and type.  Traverse a reference list if
 316  *              necessary to get to the base object.
 317  *
 318  ******************************************************************************/
 319
 320 acpi_status
 321 acpi_ex_resolve_multiple (
 322         struct acpi_walk_state          *walk_state,
 323         union acpi_operand_object       *operand,
 324         acpi_object_type                *return_type,
 325         union acpi_operand_object       **return_desc)
 326 {
 327         union acpi_operand_object       *obj_desc = (void *) operand;
 328         struct acpi_namespace_node      *node;
 329         acpi_object_type                type;
 330
 331
 332         ACPI_FUNCTION_TRACE ("acpi_ex_resolve_multiple");
 333
 334
 335         /*
 336          * For reference objects created via the ref_of or Index operators,
 337          * we need to get to the base object (as per the ACPI specification
 338          * of the object_type and size_of operators). This means traversing
 339          * the list of possibly many nested references.
 340          */
 341         while (ACPI_GET_OBJECT_TYPE (obj_desc) == ACPI_TYPE_LOCAL_REFERENCE) {
 342                 switch (obj_desc->reference.opcode) {
 343                 case AML_REF_OF_OP:
 344
 345                         /* Dereference the reference pointer */
 346
 347                         node = obj_desc->reference.object;
 348
 349                         /* All "References" point to a NS node */
 350
 351                         if (ACPI_GET_DESCRIPTOR_TYPE (node) != ACPI_DESC_TYPE_NAMED) {
 352                                 ACPI_REPORT_ERROR (("acpi_ex_resolve_multiple: Not a NS node %p [%s]\n",
 353                                                 node, acpi_ut_get_descriptor_name (node)));
 354                                 return_ACPI_STATUS (AE_AML_INTERNAL);
 355                         }
 356
 357                         /* Get the attached object */
 358
 359                         obj_desc = acpi_ns_get_attached_object (node);
 360                         if (!obj_desc) {
 361                                 /* No object, use the NS node type */
 362
 363                                 type = acpi_ns_get_type (node);
 364                                 goto exit;
 365                         }
 366
 367                         /* Check for circular references */
 368
 369                         if (obj_desc == operand) {
 370                                 return_ACPI_STATUS (AE_AML_CIRCULAR_REFERENCE);
 371                         }
 372                         break;
 373
 374
 375                 case AML_INDEX_OP:
 376
 377                         /* Get the type of this reference (index into another object) */
 378
 379                         type = obj_desc->reference.target_type;
 380                         if (type != ACPI_TYPE_PACKAGE) {
 381                                 goto exit;
 382                         }
 383
 384                         /*
 385                          * The main object is a package, we want to get the type
 386                          * of the individual package element that is referenced by
 387                          * the index.
 388                          *
 389                          * This could of course in turn be another reference object.
 390                          */
 391                         obj_desc = *(obj_desc->reference.where);
 392                         break;
 393
 394
 395                 case AML_INT_NAMEPATH_OP:
 396
 397                         /* Dereference the reference pointer */
 398
 399                         node = obj_desc->reference.node;
 400
 401                         /* All "References" point to a NS node */
 402
 403                         if (ACPI_GET_DESCRIPTOR_TYPE (node) != ACPI_DESC_TYPE_NAMED) {
 404                                 ACPI_REPORT_ERROR (("acpi_ex_resolve_multiple: Not a NS node %p [%s]\n",
 405                                                 node, acpi_ut_get_descriptor_name (node)));
 406                            return_ACPI_STATUS (AE_AML_INTERNAL);
 407                         }
 408
 409                         /* Get the attached object */
 410
 411                         obj_desc = acpi_ns_get_attached_object (node);
 412                         if (!obj_desc) {
 413                                 /* No object, use the NS node type */
 414
 415                                 type = acpi_ns_get_type (node);
 416                                 goto exit;
 417                         }
 418
 419                         /* Check for circular references */
 420
 421                         if (obj_desc == operand) {
 422                                 return_ACPI_STATUS (AE_AML_CIRCULAR_REFERENCE);
 423                         }
 424                         break;
 425
 426
 427                 case AML_DEBUG_OP:
 428
 429                         /* The Debug Object is of type "debug_object" */
 430
 431                         type = ACPI_TYPE_DEBUG_OBJECT;
 432                         goto exit;
 433
 434
 435                 default:
 436
 437                         ACPI_REPORT_ERROR (("acpi_ex_resolve_multiple: Unknown Reference subtype %X\n",
 438                                 obj_desc->reference.opcode));
 439                         return_ACPI_STATUS (AE_AML_INTERNAL);
 440                 }
 441         }
 442
 443         /*
 444          * Now we are guaranteed to have an object that has not been created
 445          * via the ref_of or Index operators.
 446          */
 447         type = ACPI_GET_OBJECT_TYPE (obj_desc);
 448
 449
 450 exit:
 451         /* Convert internal types to external types */
 452
 453         switch (type) {
 454         case ACPI_TYPE_LOCAL_REGION_FIELD:
 455         case ACPI_TYPE_LOCAL_BANK_FIELD:
 456         case ACPI_TYPE_LOCAL_INDEX_FIELD:
 457
 458                 type = ACPI_TYPE_FIELD_UNIT;
 459                 break;
 460
 461         case ACPI_TYPE_LOCAL_SCOPE:
 462
 463                 /* Per ACPI Specification, Scope is untyped */
 464
 465                 type = ACPI_TYPE_ANY;
 466                 break;
 467
 468         default:
 469                 /* No change to Type required */
 470                 break;
 471         }
 472
 473         *return_type = type;
 474         if (return_desc) {
 475                 *return_desc = obj_desc;
 476         }
 477         return_ACPI_STATUS (AE_OK);
 478 }
 479
 480