drivers/acpi/tables/tbxfroot.c

   1 /******************************************************************************
   2  *
   3  * Module Name: tbxfroot - Find the root ACPI table (RSDT)
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2004, 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
  45 #include <acpi/acpi.h>
  46 #include <acpi/actables.h>
  47
  48
  49 #define _COMPONENT          ACPI_TABLES
  50          ACPI_MODULE_NAME    ("tbxfroot")
  51
  52
  53 /*******************************************************************************
  54  *
  55  * FUNCTION:    acpi_tb_find_table
  56  *
  57  * PARAMETERS:  Signature           - String with ACPI table signature
  58  *              oem_id              - String with the table OEM ID
  59  *              oem_table_id        - String with the OEM Table ID.
  60  *
  61  * RETURN:      Status
  62  *
  63  * DESCRIPTION: Find an ACPI table (in the RSDT/XSDT) that matches the
  64  *              Signature, OEM ID and OEM Table ID.
  65  *
  66  ******************************************************************************/
  67
  68 acpi_status
  69 acpi_tb_find_table (
  70         char                            *signature,
  71         char                            *oem_id,
  72         char                            *oem_table_id,
  73         struct acpi_table_header        **table_ptr)
  74 {
  75         acpi_status                     status;
  76         struct acpi_table_header        *table;
  77
  78
  79         ACPI_FUNCTION_TRACE ("tb_find_table");
  80
  81
  82         /* Validate string lengths */
  83
  84         if ((ACPI_STRLEN (signature)  > ACPI_NAME_SIZE) ||
  85                 (ACPI_STRLEN (oem_id)     > sizeof (table->oem_id)) ||
  86                 (ACPI_STRLEN (oem_table_id) > sizeof (table->oem_table_id))) {
  87                 return_ACPI_STATUS (AE_AML_STRING_LIMIT);
  88         }
  89
  90         /* Find the table */
  91
  92         status = acpi_get_firmware_table (signature, 1,
  93                            ACPI_LOGICAL_ADDRESSING, &table);
  94         if (ACPI_FAILURE (status)) {
  95                 return_ACPI_STATUS (status);
  96         }
  97
  98         /* Check oem_id and oem_table_id */
  99
 100         if ((oem_id[0]     && ACPI_STRCMP (oem_id, table->oem_id)) ||
 101                 (oem_table_id[0] && ACPI_STRCMP (oem_table_id, table->oem_table_id))) {
 102                 return_ACPI_STATUS (AE_AML_NAME_NOT_FOUND);
 103         }
 104
 105         *table_ptr = table;
 106         return_ACPI_STATUS (AE_OK);
 107 }
 108
 109
 110 /*******************************************************************************
 111  *
 112  * FUNCTION:    acpi_get_firmware_table
 113  *
 114  * PARAMETERS:  Signature       - Any ACPI table signature
 115  *              Instance        - the non zero instance of the table, allows
 116  *                                support for multiple tables of the same type
 117  *              Flags           - Physical/Virtual support
 118  *              ret_buffer      - pointer to a structure containing a buffer to
 119  *                                receive the table
 120  *
 121  * RETURN:      Status
 122  *
 123  * DESCRIPTION: This function is called to get an ACPI table.  The caller
 124  *              supplies an out_buffer large enough to contain the entire ACPI
 125  *              table.  Upon completion
 126  *              the out_buffer->Length field will indicate the number of bytes
 127  *              copied into the out_buffer->buf_ptr buffer. This table will be
 128  *              a complete table including the header.
 129  *
 130  ******************************************************************************/
 131
 132 acpi_status
 133 acpi_get_firmware_table (
 134         acpi_string                     signature,
 135         u32                             instance,
 136         u32                             flags,
 137         struct acpi_table_header        **table_pointer)
 138 {
 139         struct acpi_pointer             rsdp_address;
 140         struct acpi_pointer             address;
 141         acpi_status                     status;
 142         struct acpi_table_header        header;
 143         struct acpi_table_desc          table_info;
 144         struct acpi_table_desc          rsdt_info;
 145         u32                             table_count;
 146         u32                             i;
 147         u32                             j;
 148
 149
 150         ACPI_FUNCTION_TRACE ("acpi_get_firmware_table");
 151
 152
 153         /*
 154          * Ensure that at least the table manager is initialized.  We don't
 155          * require that the entire ACPI subsystem is up for this interface
 156          */
 157
 158         /*
 159          *  If we have a buffer, we must have a length too
 160          */
 161         if ((instance == 0)                 ||
 162                 (!signature)                    ||
 163                 (!table_pointer)) {
 164                 return_ACPI_STATUS (AE_BAD_PARAMETER);
 165         }
 166
 167         rsdt_info.pointer = NULL;
 168
 169         if (!acpi_gbl_RSDP) {
 170                 /* Get the RSDP */
 171
 172                 status = acpi_os_get_root_pointer (flags, &rsdp_address);
 173                 if (ACPI_FAILURE (status)) {
 174                         ACPI_DEBUG_PRINT ((ACPI_DB_INFO, "RSDP  not found\n"));
 175                         return_ACPI_STATUS (AE_NO_ACPI_TABLES);
 176                 }
 177
 178                 /* Map and validate the RSDP */
 179
 180                 if ((flags & ACPI_MEMORY_MODE) == ACPI_LOGICAL_ADDRESSING) {
 181                         status = acpi_os_map_memory (rsdp_address.pointer.physical, sizeof (struct rsdp_descriptor),
 182                                           (void *) &acpi_gbl_RSDP);
 183                         if (ACPI_FAILURE (status)) {
 184                                 return_ACPI_STATUS (status);
 185                         }
 186                 }
 187                 else {
 188                         acpi_gbl_RSDP = rsdp_address.pointer.logical;
 189                 }
 190
 191                 /*
 192                  *  The signature and checksum must both be correct
 193                  */
 194                 if (ACPI_STRNCMP ((char *) acpi_gbl_RSDP, RSDP_SIG, sizeof (RSDP_SIG)-1) != 0) {
 195                         /* Nope, BAD Signature */
 196
 197                         return_ACPI_STATUS (AE_BAD_SIGNATURE);
 198                 }
 199
 200                 if (acpi_tb_checksum (acpi_gbl_RSDP, ACPI_RSDP_CHECKSUM_LENGTH) != 0) {
 201                         /* Nope, BAD Checksum */
 202
 203                         return_ACPI_STATUS (AE_BAD_CHECKSUM);
 204                 }
 205         }
 206
 207         /* Get the RSDT and validate it */
 208
 209         acpi_tb_get_rsdt_address (&address);
 210
 211         ACPI_DEBUG_PRINT ((ACPI_DB_INFO,
 212                 "RSDP located at %p, RSDT physical=%8.8X%8.8X \n",
 213                 acpi_gbl_RSDP,
 214                 ACPI_FORMAT_UINT64 (address.pointer.value)));
 215
 216         /* Insert processor_mode flags */
 217
 218         address.pointer_type |= flags;
 219
 220         status = acpi_tb_get_table (&address, &rsdt_info);
 221         if (ACPI_FAILURE (status)) {
 222                 return_ACPI_STATUS (status);
 223         }
 224
 225         status = acpi_tb_validate_rsdt (rsdt_info.pointer);
 226         if (ACPI_FAILURE (status)) {
 227                 goto cleanup;
 228         }
 229
 230         /* Get the number of table pointers within the RSDT */
 231
 232         table_count = acpi_tb_get_table_count (acpi_gbl_RSDP, rsdt_info.pointer);
 233
 234         address.pointer_type = acpi_gbl_table_flags | flags;
 235
 236         /*
 237          * Search the RSDT/XSDT for the correct instance of the
 238          * requested table
 239          */
 240         for (i = 0, j = 0; i < table_count; i++) {
 241                 /* Get the next table pointer, handle RSDT vs. XSDT */
 242
 243                 if (acpi_gbl_RSDP->revision < 2) {
 244                         address.pointer.value = (ACPI_CAST_PTR (RSDT_DESCRIPTOR, rsdt_info.pointer))->table_offset_entry[i];
 245                 }
 246                 else {
 247                         address.pointer.value =
 248                                 (ACPI_CAST_PTR (XSDT_DESCRIPTOR, rsdt_info.pointer))->table_offset_entry[i];
 249                 }
 250
 251                 /* Get the table header */
 252
 253                 status = acpi_tb_get_table_header (&address, &header);
 254                 if (ACPI_FAILURE (status)) {
 255                         goto cleanup;
 256                 }
 257
 258                 /* Compare table signatures and table instance */
 259
 260                 if (!ACPI_STRNCMP (header.signature, signature, ACPI_NAME_SIZE)) {
 261                         /* An instance of the table was found */
 262
 263                         j++;
 264                         if (j >= instance) {
 265                                 /* Found the correct instance, get the entire table */
 266
 267                                 status = acpi_tb_get_table_body (&address, &header, &table_info);
 268                                 if (ACPI_FAILURE (status)) {
 269                                         goto cleanup;
 270                                 }
 271
 272                                 *table_pointer = table_info.pointer;
 273                                 goto cleanup;
 274                         }
 275                 }
 276         }
 277
 278         /* Did not find the table */
 279
 280         status = AE_NOT_EXIST;
 281
 282
 283 cleanup:
 284         acpi_os_unmap_memory (rsdt_info.pointer, (acpi_size) rsdt_info.pointer->length);
 285         return_ACPI_STATUS (status);
 286 }
 287
 288
 289 /* TBD: Move to a new file */
 290
 291 #if ACPI_MACHINE_WIDTH != 16
 292
 293 /*******************************************************************************
 294  *
 295  * FUNCTION:    acpi_find_root_pointer
 296  *
 297  * PARAMETERS:  **rsdp_address          - Where to place the RSDP address
 298  *              Flags                   - Logical/Physical addressing
 299  *
 300  * RETURN:      Status, Physical address of the RSDP
 301  *
 302  * DESCRIPTION: Find the RSDP
 303  *
 304  ******************************************************************************/
 305
 306 acpi_status
 307 acpi_find_root_pointer (
 308         u32                             flags,
 309         struct acpi_pointer             *rsdp_address)
 310 {
 311         struct acpi_table_desc          table_info;
 312         acpi_status                     status;
 313
 314
 315         ACPI_FUNCTION_TRACE ("acpi_find_root_pointer");
 316
 317
 318         /* Get the RSDP */
 319
 320         status = acpi_tb_find_rsdp (&table_info, flags);
 321         if (ACPI_FAILURE (status)) {
 322                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "RSDP structure not found, %s Flags=%X\n",
 323                         acpi_format_exception (status), flags));
 324                 return_ACPI_STATUS (AE_NO_ACPI_TABLES);
 325         }
 326
 327         rsdp_address->pointer_type = ACPI_PHYSICAL_POINTER;
 328         rsdp_address->pointer.physical = table_info.physical_address;
 329         return_ACPI_STATUS (AE_OK);
 330 }
 331
 332
 333 /*******************************************************************************
 334  *
 335  * FUNCTION:    acpi_tb_scan_memory_for_rsdp
 336  *
 337  * PARAMETERS:  start_address       - Starting pointer for search
 338  *              Length              - Maximum length to search
 339  *
 340  * RETURN:      Pointer to the RSDP if found, otherwise NULL.
 341  *
 342  * DESCRIPTION: Search a block of memory for the RSDP signature
 343  *
 344  ******************************************************************************/
 345
 346 u8 *
 347 acpi_tb_scan_memory_for_rsdp (
 348         u8                              *start_address,
 349         u32                             length)
 350 {
 351         u32                             offset;
 352         u8                              *mem_rover;
 353
 354
 355         ACPI_FUNCTION_TRACE ("tb_scan_memory_for_rsdp");
 356
 357
 358         /* Search from given start addr for the requested length  */
 359
 360         for (offset = 0, mem_rover = start_address;
 361                  offset < length;
 362                  offset += ACPI_RSDP_SCAN_STEP, mem_rover += ACPI_RSDP_SCAN_STEP) {
 363
 364                 /* The signature and checksum must both be correct */
 365
 366                 if (ACPI_STRNCMP ((char *) mem_rover,
 367                                 RSDP_SIG, sizeof (RSDP_SIG)-1) == 0 &&
 368                         acpi_tb_checksum (mem_rover, ACPI_RSDP_CHECKSUM_LENGTH) == 0) {
 369                         /* If so, we have found the RSDP */
 370
 371                         ACPI_DEBUG_PRINT ((ACPI_DB_INFO,
 372                                 "RSDP located at physical address %p\n",mem_rover));
 373                         return_PTR (mem_rover);
 374                 }
 375         }
 376
 377         /* Searched entire block, no RSDP was found */
 378
 379         ACPI_DEBUG_PRINT ((ACPI_DB_INFO,"Searched entire block, no RSDP was found.\n"));
 380         return_PTR (NULL);
 381 }
 382
 383
 384 /*******************************************************************************
 385  *
 386  * FUNCTION:    acpi_tb_find_rsdp
 387  *
 388  * PARAMETERS:  *table_info             - Where the table info is returned
 389  *              Flags                   - Current memory mode (logical vs.
 390  *                                        physical addressing)
 391  *
 392  * RETURN:      Status
 393  *
 394  * DESCRIPTION: search lower 1_mbyte of memory for the root system descriptor
 395  *              pointer structure.  If it is found, set *RSDP to point to it.
 396  *
 397  *              NOTE: The RSDp must be either in the first 1_k of the Extended
 398  *              BIOS Data Area or between E0000 and FFFFF (ACPI 1.0 section
 399  *              5.2.2; assertion #421).
 400  *
 401  ******************************************************************************/
 402
 403 acpi_status
 404 acpi_tb_find_rsdp (
 405         struct acpi_table_desc          *table_info,
 406         u32                             flags)
 407 {
 408         u8                              *table_ptr;
 409         u8                              *mem_rover;
 410         u64                             phys_addr;
 411         acpi_status                     status = AE_OK;
 412
 413
 414         ACPI_FUNCTION_TRACE ("tb_find_rsdp");
 415
 416
 417         /*
 418          * Scan supports either 1) Logical addressing or 2) Physical addressing
 419          */
 420         if ((flags & ACPI_MEMORY_MODE) == ACPI_LOGICAL_ADDRESSING) {
 421                 /*
 422                  * 1) Search EBDA (low memory) paragraphs
 423                  */
 424                 status = acpi_os_map_memory ((u64) ACPI_LO_RSDP_WINDOW_BASE, ACPI_LO_RSDP_WINDOW_SIZE,
 425                                   (void *) &table_ptr);
 426                 if (ACPI_FAILURE (status)) {
 427                         ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Could not map memory at %X for length %X\n",
 428                                 ACPI_LO_RSDP_WINDOW_BASE, ACPI_LO_RSDP_WINDOW_SIZE));
 429                         return_ACPI_STATUS (status);
 430                 }
 431
 432                 mem_rover = acpi_tb_scan_memory_for_rsdp (table_ptr, ACPI_LO_RSDP_WINDOW_SIZE);
 433                 acpi_os_unmap_memory (table_ptr, ACPI_LO_RSDP_WINDOW_SIZE);
 434
 435                 if (mem_rover) {
 436                         /* Found it, return the physical address */
 437
 438                         phys_addr = ACPI_LO_RSDP_WINDOW_BASE;
 439                         phys_addr += ACPI_PTR_DIFF (mem_rover,table_ptr);
 440
 441                         table_info->physical_address = phys_addr;
 442                         return_ACPI_STATUS (AE_OK);
 443                 }
 444
 445                 /*
 446                  * 2) Search upper memory: 16-byte boundaries in E0000h-F0000h
 447                  */
 448                 status = acpi_os_map_memory ((u64) ACPI_HI_RSDP_WINDOW_BASE, ACPI_HI_RSDP_WINDOW_SIZE,
 449                                   (void *) &table_ptr);
 450                 if (ACPI_FAILURE (status)) {
 451                         ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Could not map memory at %X for length %X\n",
 452                                 ACPI_HI_RSDP_WINDOW_BASE, ACPI_HI_RSDP_WINDOW_SIZE));
 453                         return_ACPI_STATUS (status);
 454                 }
 455
 456                 mem_rover = acpi_tb_scan_memory_for_rsdp (table_ptr, ACPI_HI_RSDP_WINDOW_SIZE);
 457                 acpi_os_unmap_memory (table_ptr, ACPI_HI_RSDP_WINDOW_SIZE);
 458
 459                 if (mem_rover) {
 460                         /* Found it, return the physical address */
 461
 462                         phys_addr = ACPI_HI_RSDP_WINDOW_BASE;
 463                         phys_addr += ACPI_PTR_DIFF (mem_rover, table_ptr);
 464
 465                         table_info->physical_address = phys_addr;
 466                         return_ACPI_STATUS (AE_OK);
 467                 }
 468         }
 469
 470         /*
 471          * Physical addressing
 472          */
 473         else {
 474                 /*
 475                  * 1) Search EBDA (low memory) paragraphs
 476                  */
 477                 mem_rover = acpi_tb_scan_memory_for_rsdp (ACPI_PHYSADDR_TO_PTR (ACPI_LO_RSDP_WINDOW_BASE),
 478                                   ACPI_LO_RSDP_WINDOW_SIZE);
 479                 if (mem_rover) {
 480                         /* Found it, return the physical address */
 481
 482                         table_info->physical_address = ACPI_TO_INTEGER (mem_rover);
 483                         return_ACPI_STATUS (AE_OK);
 484                 }
 485
 486                 /*
 487                  * 2) Search upper memory: 16-byte boundaries in E0000h-F0000h
 488                  */
 489                 mem_rover = acpi_tb_scan_memory_for_rsdp (ACPI_PHYSADDR_TO_PTR (ACPI_HI_RSDP_WINDOW_BASE),
 490                                   ACPI_HI_RSDP_WINDOW_SIZE);
 491                 if (mem_rover) {
 492                         /* Found it, return the physical address */
 493
 494                         table_info->physical_address = ACPI_TO_INTEGER (mem_rover);
 495                         return_ACPI_STATUS (AE_OK);
 496                 }
 497         }
 498
 499         /* RSDP signature was not found */
 500
 501         return_ACPI_STATUS (AE_NOT_FOUND);
 502 }
 503
 504 #endif
 505