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                 /* Just ignore this table */
  88
  89                 return_ACPI_STATUS(AE_OK);
  90         }
  91
  92         /* Check validity of the AML start and length */
  93
  94         if (!table_desc->aml_start) {
  95                 ACPI_ERROR((AE_INFO, "Null AML pointer"));
  96                 return_ACPI_STATUS(AE_BAD_PARAMETER);
  97         }
  98
  99         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "AML block at %p\n",
 100                           table_desc->aml_start));
 101
 102         /* Ignore table if there is no AML contained within */
 103
 104         if (!table_desc->aml_length) {
 105                 ACPI_WARNING((AE_INFO, "Zero-length AML block in table [%4.4s]",
 106                               table_desc->pointer->signature));
 107                 return_ACPI_STATUS(AE_OK);
 108         }
 109
 110         /*
 111          * Parse the table and load the namespace with all named
 112          * objects found within.  Control methods are NOT parsed
 113          * at this time.  In fact, the control methods cannot be
 114          * parsed until the entire namespace is loaded, because
 115          * if a control method makes a forward reference (call)
 116          * to another control method, we can't continue parsing
 117          * because we don't know how many arguments to parse next!
 118          */
 119         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 120                           "**** Loading table into namespace ****\n"));
 121
 122         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 123         if (ACPI_FAILURE(status)) {
 124                 return_ACPI_STATUS(status);
 125         }
 126
 127         status = acpi_ns_parse_table(table_desc, node->child);
 128         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 129
 130         if (ACPI_FAILURE(status)) {
 131                 return_ACPI_STATUS(status);
 132         }
 133
 134         /*
 135          * Now we can parse the control methods.  We always parse
 136          * them here for a sanity check, and if configured for
 137          * just-in-time parsing, we delete the control method
 138          * parse trees.
 139          */
 140         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 141                           "**** Begin Table Method Parsing and Object Initialization ****\n"));
 142
 143         status = acpi_ds_initialize_objects(table_desc, node);
 144
 145         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 146                           "**** Completed Table Method Parsing and Object Initialization ****\n"));
 147
 148         return_ACPI_STATUS(status);
 149 }
 150
 151 /*******************************************************************************
 152  *
 153  * FUNCTION:    acpi_ns_load_table_by_type
 154  *
 155  * PARAMETERS:  table_type          - Id of the table type to load
 156  *
 157  * RETURN:      Status
 158  *
 159  * DESCRIPTION: Load an ACPI table or tables into the namespace.  All tables
 160  *              of the given type are loaded.  The mechanism allows this
 161  *              routine to be called repeatedly.
 162  *
 163  ******************************************************************************/
 164
 165 static acpi_status acpi_ns_load_table_by_type(acpi_table_type table_type)
 166 {
 167         u32 i;
 168         acpi_status status;
 169         struct acpi_table_desc *table_desc;
 170
 171         ACPI_FUNCTION_TRACE("ns_load_table_by_type");
 172
 173         status = acpi_ut_acquire_mutex(ACPI_MTX_TABLES);
 174         if (ACPI_FAILURE(status)) {
 175                 return_ACPI_STATUS(status);
 176         }
 177
 178         /*
 179          * Table types supported are:
 180          * DSDT (one), SSDT/PSDT (multiple)
 181          */
 182         switch (table_type) {
 183         case ACPI_TABLE_DSDT:
 184
 185                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Namespace load: DSDT\n"));
 186
 187                 table_desc = acpi_gbl_table_lists[ACPI_TABLE_DSDT].next;
 188
 189                 /* If table already loaded into namespace, just return */
 190
 191                 if (table_desc->loaded_into_namespace) {
 192                         goto unlock_and_exit;
 193                 }
 194
 195                 /* Now load the single DSDT */
 196
 197                 status = acpi_ns_load_table(table_desc, acpi_gbl_root_node);
 198                 if (ACPI_SUCCESS(status)) {
 199                         table_desc->loaded_into_namespace = TRUE;
 200                 }
 201                 break;
 202
 203         case ACPI_TABLE_SSDT:
 204         case ACPI_TABLE_PSDT:
 205
 206                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 207                                   "Namespace load: %d SSDT or PSDTs\n",
 208                                   acpi_gbl_table_lists[table_type].count));
 209
 210                 /*
 211                  * Traverse list of SSDT or PSDT tables
 212                  */
 213                 table_desc = acpi_gbl_table_lists[table_type].next;
 214                 for (i = 0; i < acpi_gbl_table_lists[table_type].count; i++) {
 215                         /*
 216                          * Only attempt to load table into namespace if it is not
 217                          * already loaded!
 218                          */
 219                         if (!table_desc->loaded_into_namespace) {
 220                                 status =
 221                                     acpi_ns_load_table(table_desc,
 222                                                        acpi_gbl_root_node);
 223                                 if (ACPI_FAILURE(status)) {
 224                                         break;
 225                                 }
 226
 227                                 table_desc->loaded_into_namespace = TRUE;
 228                         }
 229
 230                         table_desc = table_desc->next;
 231                 }
 232                 break;
 233
 234         default:
 235                 status = AE_SUPPORT;
 236                 break;
 237         }
 238
 239       unlock_and_exit:
 240         (void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
 241         return_ACPI_STATUS(status);
 242 }
 243
 244 /*******************************************************************************
 245  *
 246  * FUNCTION:    acpi_load_namespace
 247  *
 248  * PARAMETERS:  None
 249  *
 250  * RETURN:      Status
 251  *
 252  * DESCRIPTION: Load the name space from what ever is pointed to by DSDT.
 253  *              (DSDT points to either the BIOS or a buffer.)
 254  *
 255  ******************************************************************************/
 256
 257 acpi_status acpi_ns_load_namespace(void)
 258 {
 259         acpi_status status;
 260
 261         ACPI_FUNCTION_TRACE("acpi_load_name_space");
 262
 263         /* There must be at least a DSDT installed */
 264
 265         if (acpi_gbl_DSDT == NULL) {
 266                 ACPI_ERROR((AE_INFO, "DSDT is not in memory"));
 267                 return_ACPI_STATUS(AE_NO_ACPI_TABLES);
 268         }
 269
 270         /*
 271          * Load the namespace.  The DSDT is required,
 272          * but the SSDT and PSDT tables are optional.
 273          */
 274         status = acpi_ns_load_table_by_type(ACPI_TABLE_DSDT);
 275         if (ACPI_FAILURE(status)) {
 276                 return_ACPI_STATUS(status);
 277         }
 278
 279         /* Ignore exceptions from these */
 280
 281         (void)acpi_ns_load_table_by_type(ACPI_TABLE_SSDT);
 282         (void)acpi_ns_load_table_by_type(ACPI_TABLE_PSDT);
 283
 284         ACPI_DEBUG_PRINT_RAW((ACPI_DB_INIT,
 285                               "ACPI Namespace successfully loaded at root %p\n",
 286                               acpi_gbl_root_node));
 287
 288         return_ACPI_STATUS(status);
 289 }
 290
 291 #ifdef ACPI_FUTURE_IMPLEMENTATION
 292 /*******************************************************************************
 293  *
 294  * FUNCTION:    acpi_ns_delete_subtree
 295  *
 296  * PARAMETERS:  start_handle        - Handle in namespace where search begins
 297  *
 298  * RETURNS      Status
 299  *
 300  * DESCRIPTION: Walks the namespace starting at the given handle and deletes
 301  *              all objects, entries, and scopes in the entire subtree.
 302  *
 303  *              Namespace/Interpreter should be locked or the subsystem should
 304  *              be in shutdown before this routine is called.
 305  *
 306  ******************************************************************************/
 307
 308 static acpi_status acpi_ns_delete_subtree(acpi_handle start_handle)
 309 {
 310         acpi_status status;
 311         acpi_handle child_handle;
 312         acpi_handle parent_handle;
 313         acpi_handle next_child_handle;
 314         acpi_handle dummy;
 315         u32 level;
 316
 317         ACPI_FUNCTION_TRACE("ns_delete_subtree");
 318
 319         parent_handle = start_handle;
 320         child_handle = NULL;
 321         level = 1;
 322
 323         /*
 324          * Traverse the tree of objects until we bubble back up
 325          * to where we started.
 326          */
 327         while (level > 0) {
 328                 /* Attempt to get the next object in this scope */
 329
 330                 status = acpi_get_next_object(ACPI_TYPE_ANY, parent_handle,
 331                                               child_handle, &next_child_handle);
 332
 333                 child_handle = next_child_handle;
 334
 335                 /* Did we get a new object? */
 336
 337                 if (ACPI_SUCCESS(status)) {
 338                         /* Check if this object has any children */
 339
 340                         if (ACPI_SUCCESS
 341                             (acpi_get_next_object
 342                              (ACPI_TYPE_ANY, child_handle, NULL, &dummy))) {
 343                                 /*
 344                                  * There is at least one child of this object,
 345                                  * visit the object
 346                                  */
 347                                 level++;
 348                                 parent_handle = child_handle;
 349                                 child_handle = NULL;
 350                         }
 351                 } else {
 352                         /*
 353                          * No more children in this object, go back up to
 354                          * the object's parent
 355                          */
 356                         level--;
 357
 358                         /* Delete all children now */
 359
 360                         acpi_ns_delete_children(child_handle);
 361
 362                         child_handle = parent_handle;
 363                         status = acpi_get_parent(parent_handle, &parent_handle);
 364                         if (ACPI_FAILURE(status)) {
 365                                 return_ACPI_STATUS(status);
 366                         }
 367                 }
 368         }
 369
 370         /* Now delete the starting object, and we are done */
 371
 372         acpi_ns_delete_node(child_handle);
 373
 374         return_ACPI_STATUS(AE_OK);
 375 }
 376
 377 /*******************************************************************************
 378  *
 379  *  FUNCTION:       acpi_ns_unload_name_space
 380  *
 381  *  PARAMETERS:     Handle          - Root of namespace subtree to be deleted
 382  *
 383  *  RETURN:         Status
 384  *
 385  *  DESCRIPTION:    Shrinks the namespace, typically in response to an undocking
 386  *                  event.  Deletes an entire subtree starting from (and
 387  *                  including) the given handle.
 388  *
 389  ******************************************************************************/
 390
 391 acpi_status acpi_ns_unload_namespace(acpi_handle handle)
 392 {
 393         acpi_status status;
 394
 395         ACPI_FUNCTION_TRACE("ns_unload_name_space");
 396
 397         /* Parameter validation */
 398
 399         if (!acpi_gbl_root_node) {
 400                 return_ACPI_STATUS(AE_NO_NAMESPACE);
 401         }
 402
 403         if (!handle) {
 404                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 405         }
 406
 407         /* This function does the real work */
 408
 409         status = acpi_ns_delete_subtree(handle);
 410
 411         return_ACPI_STATUS(status);
 412 }
 413 #endif
 414 #endif