err.no Git - linux-2.6/blob - drivers/acpi/namespace/nsload.c

   1 /******************************************************************************
   2  *
   3  * Module Name: nsload - namespace loading/expanding/contracting procedures
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2006, R. Byron Moore
   9  * All rights reserved.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions, and the following disclaimer,
  16  *    without modification.
  17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  18  *    substantially similar to the "NO WARRANTY" disclaimer below
  19  *    ("Disclaimer") and any redistribution must be conditioned upon
  20  *    including a substantially similar Disclaimer requirement for further
  21  *    binary redistribution.
  22  * 3. Neither the names of the above-listed copyright holders nor the names
  23  *    of any contributors may be used to endorse or promote products derived
  24  *    from this software without specific prior written permission.
  25  *
  26  * Alternatively, this software may be distributed under the terms of the
  27  * GNU General Public License ("GPL") version 2 as published by the Free
  28  * Software Foundation.
  29  *
  30  * NO WARRANTY
  31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
  34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  41  * POSSIBILITY OF SUCH DAMAGES.
  42  */
  43
  44 #include <acpi/acpi.h>
  45 #include <acpi/acnamesp.h>
  46 #include <acpi/acdispat.h>
  47
  48 #define _COMPONENT          ACPI_NAMESPACE
  49 ACPI_MODULE_NAME("nsload")
  50
  51 /* Local prototypes */
  52 static acpi_status acpi_ns_load_table_by_type(acpi_table_type table_type);
  53
  54 #ifdef ACPI_FUTURE_IMPLEMENTATION
  55 acpi_status acpi_ns_unload_namespace(acpi_handle handle);
  56
  57 static acpi_status acpi_ns_delete_subtree(acpi_handle start_handle);
  58 #endif
  59
  60 #ifndef ACPI_NO_METHOD_EXECUTION
  61 /*******************************************************************************
  62  *
  63  * FUNCTION:    acpi_ns_load_table
  64  *
  65  * PARAMETERS:  table_desc      - Descriptor for table to be loaded
  66  *              Node            - Owning NS node
  67  *
  68  * RETURN:      Status
  69  *
  70  * DESCRIPTION: Load one ACPI table into the namespace
  71  *
  72  ******************************************************************************/
  73
  74 acpi_status
  75 acpi_ns_load_table(struct acpi_table_desc *table_desc,
  76                    struct acpi_namespace_node *node)
  77 {
  78         acpi_status status;
  79
  80         ACPI_FUNCTION_TRACE(ns_load_table);
  81
  82         /* Check if table contains valid AML (must be DSDT, PSDT, SSDT, etc.) */
  83
  84         if (!
  85             (acpi_gbl_table_data[table_desc->type].
  86              flags & ACPI_TABLE_EXECUTABLE)) {
  87
  88                 /* Just ignore this table */
  89
  90                 return_ACPI_STATUS(AE_OK);
  91         }
  92
  93         /* Check validity of the AML start and length */
  94
  95         if (!table_desc->aml_start) {
  96                 ACPI_ERROR((AE_INFO, "Null AML pointer"));
  97                 return_ACPI_STATUS(AE_BAD_PARAMETER);
  98         }
  99
 100         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "AML block at %p\n",
 101                           table_desc->aml_start));
 102
 103         /* Ignore table if there is no AML contained within */
 104
 105         if (!table_desc->aml_length) {
 106                 ACPI_WARNING((AE_INFO, "Zero-length AML block in table [%4.4s]",
 107                               table_desc->pointer->signature));
 108                 return_ACPI_STATUS(AE_OK);
 109         }
 110
 111         /*
 112          * Parse the table and load the namespace with all named
 113          * objects found within.  Control methods are NOT parsed
 114          * at this time.  In fact, the control methods cannot be
 115          * parsed until the entire namespace is loaded, because
 116          * if a control method makes a forward reference (call)
 117          * to another control method, we can't continue parsing
 118          * because we don't know how many arguments to parse next!
 119          */
 120         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 121                           "**** Loading table into namespace ****\n"));
 122
 123         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 124         if (ACPI_FAILURE(status)) {
 125                 return_ACPI_STATUS(status);
 126         }
 127
 128         status = acpi_ns_parse_table(table_desc, node->child);
 129         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 130
 131         if (ACPI_FAILURE(status)) {
 132                 return_ACPI_STATUS(status);
 133         }
 134
 135         /*
 136          * Now we can parse the control methods.  We always parse
 137          * them here for a sanity check, and if configured for
 138          * just-in-time parsing, we delete the control method
 139          * parse trees.
 140          */
 141         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 142                           "**** Begin Table Method Parsing and Object Initialization ****\n"));
 143
 144         status = acpi_ds_initialize_objects(table_desc, node);
 145
 146         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 147                           "**** Completed Table Method Parsing and Object Initialization ****\n"));
 148
 149         return_ACPI_STATUS(status);
 150 }
 151
 152 /*******************************************************************************
 153  *
 154  * FUNCTION:    acpi_ns_load_table_by_type
 155  *
 156  * PARAMETERS:  table_type          - Id of the table type to load
 157  *
 158  * RETURN:      Status
 159  *
 160  * DESCRIPTION: Load an ACPI table or tables into the namespace.  All tables
 161  *              of the given type are loaded.  The mechanism allows this
 162  *              routine to be called repeatedly.
 163  *
 164  ******************************************************************************/
 165
 166 static acpi_status acpi_ns_load_table_by_type(acpi_table_type table_type)
 167 {
 168         u32 i;
 169         acpi_status status;
 170         struct acpi_table_desc *table_desc;
 171
 172         ACPI_FUNCTION_TRACE(ns_load_table_by_type);
 173
 174         status = acpi_ut_acquire_mutex(ACPI_MTX_TABLES);
 175         if (ACPI_FAILURE(status)) {
 176                 return_ACPI_STATUS(status);
 177         }
 178
 179         /*
 180          * Table types supported are:
 181          * DSDT (one), SSDT/PSDT (multiple)
 182          */
 183         switch (table_type) {
 184         case ACPI_TABLE_ID_DSDT:
 185
 186                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Namespace load: DSDT\n"));
 187
 188                 table_desc = acpi_gbl_table_lists[ACPI_TABLE_ID_DSDT].next;
 189
 190                 /* If table already loaded into namespace, just return */
 191
 192                 if (table_desc->loaded_into_namespace) {
 193                         goto unlock_and_exit;
 194                 }
 195
 196                 /* Now load the single DSDT */
 197
 198                 status = acpi_ns_load_table(table_desc, acpi_gbl_root_node);
 199                 if (ACPI_SUCCESS(status)) {
 200                         table_desc->loaded_into_namespace = TRUE;
 201                 }
 202                 break;
 203
 204         case ACPI_TABLE_ID_SSDT:
 205         case ACPI_TABLE_ID_PSDT:
 206
 207                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 208                                   "Namespace load: %d SSDT or PSDTs\n",
 209                                   acpi_gbl_table_lists[table_type].count));
 210
 211                 /*
 212                  * Traverse list of SSDT or PSDT tables
 213                  */
 214                 table_desc = acpi_gbl_table_lists[table_type].next;
 215                 for (i = 0; i < acpi_gbl_table_lists[table_type].count; i++) {
 216                         /*
 217                          * Only attempt to load table into namespace if it is not
 218                          * already loaded!
 219                          */
 220                         if (!table_desc->loaded_into_namespace) {
 221                                 status =
 222                                     acpi_ns_load_table(table_desc,
 223                                                        acpi_gbl_root_node);
 224                                 if (ACPI_FAILURE(status)) {
 225                                         break;
 226                                 }
 227
 228                                 table_desc->loaded_into_namespace = TRUE;
 229                         }
 230
 231                         table_desc = table_desc->next;
 232                 }
 233                 break;
 234
 235         default:
 236                 status = AE_SUPPORT;
 237                 break;
 238         }
 239
 240       unlock_and_exit:
 241         (void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
 242         return_ACPI_STATUS(status);
 243 }
 244
 245 /*******************************************************************************
 246  *
 247  * FUNCTION:    acpi_load_namespace
 248  *
 249  * PARAMETERS:  None
 250  *
 251  * RETURN:      Status
 252  *
 253  * DESCRIPTION: Load the name space from what ever is pointed to by DSDT.
 254  *              (DSDT points to either the BIOS or a buffer.)
 255  *
 256  ******************************************************************************/
 257
 258 acpi_status acpi_ns_load_namespace(void)
 259 {
 260         acpi_status status;
 261
 262         ACPI_FUNCTION_TRACE(acpi_load_name_space);
 263
 264         /* There must be at least a DSDT installed */
 265
 266         if (acpi_gbl_DSDT == NULL) {
 267                 ACPI_ERROR((AE_INFO, "DSDT is not in memory"));
 268                 return_ACPI_STATUS(AE_NO_ACPI_TABLES);
 269         }
 270
 271         /*
 272          * Load the namespace.  The DSDT is required,
 273          * but the SSDT and PSDT tables are optional.
 274          */
 275         status = acpi_ns_load_table_by_type(ACPI_TABLE_ID_DSDT);
 276         if (ACPI_FAILURE(status)) {
 277                 return_ACPI_STATUS(status);
 278         }
 279
 280         /* Ignore exceptions from these */
 281
 282         (void)acpi_ns_load_table_by_type(ACPI_TABLE_ID_SSDT);
 283         (void)acpi_ns_load_table_by_type(ACPI_TABLE_ID_PSDT);
 284
 285         ACPI_DEBUG_PRINT_RAW((ACPI_DB_INIT,
 286                               "ACPI Namespace successfully loaded at root %p\n",
 287                               acpi_gbl_root_node));
 288
 289         return_ACPI_STATUS(status);
 290 }
 291
 292 #ifdef ACPI_FUTURE_IMPLEMENTATION
 293 /*******************************************************************************
 294  *
 295  * FUNCTION:    acpi_ns_delete_subtree
 296  *
 297  * PARAMETERS:  start_handle        - Handle in namespace where search begins
 298  *
 299  * RETURNS      Status
 300  *
 301  * DESCRIPTION: Walks the namespace starting at the given handle and deletes
 302  *              all objects, entries, and scopes in the entire subtree.
 303  *
 304  *              Namespace/Interpreter should be locked or the subsystem should
 305  *              be in shutdown before this routine is called.
 306  *
 307  ******************************************************************************/
 308
 309 static acpi_status acpi_ns_delete_subtree(acpi_handle start_handle)
 310 {
 311         acpi_status status;
 312         acpi_handle child_handle;
 313         acpi_handle parent_handle;
 314         acpi_handle next_child_handle;
 315         acpi_handle dummy;
 316         u32 level;
 317
 318         ACPI_FUNCTION_TRACE(ns_delete_subtree);
 319
 320         parent_handle = start_handle;
 321         child_handle = NULL;
 322         level = 1;
 323
 324         /*
 325          * Traverse the tree of objects until we bubble back up
 326          * to where we started.
 327          */
 328         while (level > 0) {
 329
 330                 /* Attempt to get the next object in this scope */
 331
 332                 status = acpi_get_next_object(ACPI_TYPE_ANY, parent_handle,
 333                                               child_handle, &next_child_handle);
 334
 335                 child_handle = next_child_handle;
 336
 337                 /* Did we get a new object? */
 338
 339                 if (ACPI_SUCCESS(status)) {
 340
 341                         /* Check if this object has any children */
 342
 343                         if (ACPI_SUCCESS
 344                             (acpi_get_next_object
 345                              (ACPI_TYPE_ANY, child_handle, NULL, &dummy))) {
 346                                 /*
 347                                  * There is at least one child of this object,
 348                                  * visit the object
 349                                  */
 350                                 level++;
 351                                 parent_handle = child_handle;
 352                                 child_handle = NULL;
 353                         }
 354                 } else {
 355                         /*
 356                          * No more children in this object, go back up to
 357                          * the object's parent
 358                          */
 359                         level--;
 360
 361                         /* Delete all children now */
 362
 363                         acpi_ns_delete_children(child_handle);
 364
 365                         child_handle = parent_handle;
 366                         status = acpi_get_parent(parent_handle, &parent_handle);
 367                         if (ACPI_FAILURE(status)) {
 368                                 return_ACPI_STATUS(status);
 369                         }
 370                 }
 371         }
 372
 373         /* Now delete the starting object, and we are done */
 374
 375         acpi_ns_delete_node(child_handle);
 376
 377         return_ACPI_STATUS(AE_OK);
 378 }
 379
 380 /*******************************************************************************
 381  *
 382  *  FUNCTION:       acpi_ns_unload_name_space
 383  *
 384  *  PARAMETERS:     Handle          - Root of namespace subtree to be deleted
 385  *
 386  *  RETURN:         Status
 387  *
 388  *  DESCRIPTION:    Shrinks the namespace, typically in response to an undocking
 389  *                  event.  Deletes an entire subtree starting from (and
 390  *                  including) the given handle.
 391  *
 392  ******************************************************************************/
 393
 394 acpi_status acpi_ns_unload_namespace(acpi_handle handle)
 395 {
 396         acpi_status status;
 397
 398         ACPI_FUNCTION_TRACE(ns_unload_name_space);
 399
 400         /* Parameter validation */
 401
 402         if (!acpi_gbl_root_node) {
 403                 return_ACPI_STATUS(AE_NO_NAMESPACE);
 404         }
 405
 406         if (!handle) {
 407                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 408         }
 409
 410         /* This function does the real work */
 411
 412         status = acpi_ns_delete_subtree(handle);
 413
 414         return_ACPI_STATUS(status);
 415 }
 416 #endif
 417 #endif