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  *              table_pointer   - Where a buffer containing the table is
 119  *                                returned
 120  *
 121  * RETURN:      Status
 122  *
 123  * DESCRIPTION: This function is called to get an ACPI table. A buffer is
 124  *              allocated for the table and returned in table_pointer.
 125  *              This table will be a complete table including the header.
 126  *
 127  ******************************************************************************/
 128
 129 acpi_status
 130 acpi_get_firmware_table (
 131         acpi_string                     signature,
 132         u32                             instance,
 133         u32                             flags,
 134         struct acpi_table_header        **table_pointer)
 135 {
 136         acpi_status                     status;
 137         struct acpi_pointer             address;
 138         struct acpi_table_header        *header = NULL;
 139         struct acpi_table_desc          *table_info = NULL;
 140         struct acpi_table_desc          *rsdt_info;
 141         u32                             table_count;
 142         u32                             i;
 143         u32                             j;
 144
 145
 146         ACPI_FUNCTION_TRACE ("acpi_get_firmware_table");
 147
 148
 149         /*
 150          * Ensure that at least the table manager is initialized.  We don't
 151          * require that the entire ACPI subsystem is up for this interface.
 152          * If we have a buffer, we must have a length too
 153          */
 154         if ((instance == 0)     ||
 155                 (!signature)        ||
 156                 (!table_pointer)) {
 157                 return_ACPI_STATUS (AE_BAD_PARAMETER);
 158         }
 159
 160         /* Ensure that we have a RSDP */
 161
 162         if (!acpi_gbl_RSDP) {
 163                 /* Get the RSDP */
 164
 165                 status = acpi_os_get_root_pointer (flags, &address);
 166                 if (ACPI_FAILURE (status)) {
 167                         ACPI_DEBUG_PRINT ((ACPI_DB_INFO, "RSDP not found\n"));
 168                         return_ACPI_STATUS (AE_NO_ACPI_TABLES);
 169                 }
 170
 171                 /* Map and validate the RSDP */
 172
 173                 if ((flags & ACPI_MEMORY_MODE) == ACPI_LOGICAL_ADDRESSING) {
 174                         status = acpi_os_map_memory (address.pointer.physical, sizeof (struct rsdp_descriptor),
 175                                           (void *) &acpi_gbl_RSDP);
 176                         if (ACPI_FAILURE (status)) {
 177                                 return_ACPI_STATUS (status);
 178                         }
 179                 }
 180                 else {
 181                         acpi_gbl_RSDP = address.pointer.logical;
 182                 }
 183
 184                 /* The signature and checksum must both be correct */
 185
 186                 if (ACPI_STRNCMP ((char *) acpi_gbl_RSDP, RSDP_SIG, sizeof (RSDP_SIG)-1) != 0) {
 187                         /* Nope, BAD Signature */
 188
 189                         return_ACPI_STATUS (AE_BAD_SIGNATURE);
 190                 }
 191
 192                 if (acpi_tb_checksum (acpi_gbl_RSDP, ACPI_RSDP_CHECKSUM_LENGTH) != 0) {
 193                         /* Nope, BAD Checksum */
 194
 195                         return_ACPI_STATUS (AE_BAD_CHECKSUM);
 196                 }
 197         }
 198
 199         /* Get the RSDT address via the RSDP */
 200
 201         acpi_tb_get_rsdt_address (&address);
 202         ACPI_DEBUG_PRINT ((ACPI_DB_INFO,
 203                 "RSDP located at %p, RSDT physical=%8.8X%8.8X \n",
 204                 acpi_gbl_RSDP,
 205                 ACPI_FORMAT_UINT64 (address.pointer.value)));
 206
 207         /* Insert processor_mode flags */
 208
 209         address.pointer_type |= flags;
 210
 211         /* Get and validate the RSDT */
 212
 213         rsdt_info = ACPI_MEM_CALLOCATE (sizeof (struct acpi_table_desc));
 214         if (!rsdt_info) {
 215                 return_ACPI_STATUS (AE_NO_MEMORY);
 216         }
 217
 218         status = acpi_tb_get_table (&address, rsdt_info);
 219         if (ACPI_FAILURE (status)) {
 220                 goto cleanup;
 221         }
 222
 223         status = acpi_tb_validate_rsdt (rsdt_info->pointer);
 224         if (ACPI_FAILURE (status)) {
 225                 goto cleanup;
 226         }
 227
 228         /* Allocate a scratch table header and table descriptor */
 229
 230         header = ACPI_MEM_ALLOCATE (sizeof (struct acpi_table_header));
 231         if (!header) {
 232                 status = AE_NO_MEMORY;
 233                 goto cleanup;
 234         }
 235
 236         table_info = ACPI_MEM_ALLOCATE (sizeof (struct acpi_table_desc));
 237         if (!table_info) {
 238                 status = AE_NO_MEMORY;
 239                 goto cleanup;
 240         }
 241
 242         /* Get the number of table pointers within the RSDT */
 243
 244         table_count = acpi_tb_get_table_count (acpi_gbl_RSDP, rsdt_info->pointer);
 245         address.pointer_type = acpi_gbl_table_flags | flags;
 246
 247         /*
 248          * Search the RSDT/XSDT for the correct instance of the
 249          * requested table
 250          */
 251         for (i = 0, j = 0; i < table_count; i++) {
 252                 /* Get the next table pointer, handle RSDT vs. XSDT */
 253
 254                 if (acpi_gbl_RSDP->revision < 2) {
 255                         address.pointer.value = (ACPI_CAST_PTR (
 256                                 RSDT_DESCRIPTOR, rsdt_info->pointer))->table_offset_entry[i];
 257                 }
 258                 else {
 259                         address.pointer.value = (ACPI_CAST_PTR (
 260                                 XSDT_DESCRIPTOR, rsdt_info->pointer))->table_offset_entry[i];
 261                 }
 262
 263                 /* Get the table header */
 264
 265                 status = acpi_tb_get_table_header (&address, header);
 266                 if (ACPI_FAILURE (status)) {
 267                         goto cleanup;
 268                 }
 269
 270                 /* Compare table signatures and table instance */
 271
 272                 if (!ACPI_STRNCMP (header->signature, signature, ACPI_NAME_SIZE)) {
 273                         /* An instance of the table was found */
 274
 275                         j++;
 276                         if (j >= instance) {
 277                                 /* Found the correct instance, get the entire table */
 278
 279                                 status = acpi_tb_get_table_body (&address, header, table_info);
 280                                 if (ACPI_FAILURE (status)) {
 281                                         goto cleanup;
 282                                 }
 283
 284                                 *table_pointer = table_info->pointer;
 285                                 goto cleanup;
 286                         }
 287                 }
 288         }
 289
 290         /* Did not find the table */
 291
 292         status = AE_NOT_EXIST;
 293
 294
 295 cleanup:
 296         acpi_os_unmap_memory (rsdt_info->pointer, (acpi_size) rsdt_info->pointer->length);
 297         ACPI_MEM_FREE (rsdt_info);
 298
 299         if (header) {
 300                 ACPI_MEM_FREE (header);
 301         }
 302         if (table_info) {
 303                 ACPI_MEM_FREE (table_info);
 304         }
 305         return_ACPI_STATUS (status);
 306 }
 307
 308
 309 /* TBD: Move to a new file */
 310
 311 #if ACPI_MACHINE_WIDTH != 16
 312
 313 /*******************************************************************************
 314  *
 315  * FUNCTION:    acpi_find_root_pointer
 316  *
 317  * PARAMETERS:  **rsdp_address          - Where to place the RSDP address
 318  *              Flags                   - Logical/Physical addressing
 319  *
 320  * RETURN:      Status, Physical address of the RSDP
 321  *
 322  * DESCRIPTION: Find the RSDP
 323  *
 324  ******************************************************************************/
 325
 326 acpi_status
 327 acpi_find_root_pointer (
 328         u32                             flags,
 329         struct acpi_pointer             *rsdp_address)
 330 {
 331         struct acpi_table_desc          table_info;
 332         acpi_status                     status;
 333
 334
 335         ACPI_FUNCTION_TRACE ("acpi_find_root_pointer");
 336
 337
 338         /* Get the RSDP */
 339
 340         status = acpi_tb_find_rsdp (&table_info, flags);
 341         if (ACPI_FAILURE (status)) {
 342                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "RSDP structure not found, %s Flags=%X\n",
 343                         acpi_format_exception (status), flags));
 344                 return_ACPI_STATUS (AE_NO_ACPI_TABLES);
 345         }
 346
 347         rsdp_address->pointer_type = ACPI_PHYSICAL_POINTER;
 348         rsdp_address->pointer.physical = table_info.physical_address;
 349         return_ACPI_STATUS (AE_OK);
 350 }
 351
 352
 353 /*******************************************************************************
 354  *
 355  * FUNCTION:    acpi_tb_scan_memory_for_rsdp
 356  *
 357  * PARAMETERS:  start_address       - Starting pointer for search
 358  *              Length              - Maximum length to search
 359  *
 360  * RETURN:      Pointer to the RSDP if found, otherwise NULL.
 361  *
 362  * DESCRIPTION: Search a block of memory for the RSDP signature
 363  *
 364  ******************************************************************************/
 365
 366 u8 *
 367 acpi_tb_scan_memory_for_rsdp (
 368         u8                              *start_address,
 369         u32                             length)
 370 {
 371         u32                             offset;
 372         u8                              *mem_rover;
 373
 374
 375         ACPI_FUNCTION_TRACE ("tb_scan_memory_for_rsdp");
 376
 377
 378         /* Search from given start addr for the requested length  */
 379
 380         for (offset = 0, mem_rover = start_address;
 381                  offset < length;
 382                  offset += ACPI_RSDP_SCAN_STEP, mem_rover += ACPI_RSDP_SCAN_STEP) {
 383
 384                 /* The signature and checksum must both be correct */
 385
 386                 if (ACPI_STRNCMP ((char *) mem_rover,
 387                                 RSDP_SIG, sizeof (RSDP_SIG)-1) == 0 &&
 388                         acpi_tb_checksum (mem_rover, ACPI_RSDP_CHECKSUM_LENGTH) == 0) {
 389                         /* If so, we have found the RSDP */
 390
 391                         ACPI_DEBUG_PRINT ((ACPI_DB_INFO,
 392                                 "RSDP located at physical address %p\n",mem_rover));
 393                         return_PTR (mem_rover);
 394                 }
 395         }
 396
 397         /* Searched entire block, no RSDP was found */
 398
 399         ACPI_DEBUG_PRINT ((ACPI_DB_INFO,"Searched entire block, no RSDP was found.\n"));
 400         return_PTR (NULL);
 401 }
 402
 403
 404 /*******************************************************************************
 405  *
 406  * FUNCTION:    acpi_tb_find_rsdp
 407  *
 408  * PARAMETERS:  *table_info             - Where the table info is returned
 409  *              Flags                   - Current memory mode (logical vs.
 410  *                                        physical addressing)
 411  *
 412  * RETURN:      Status, RSDP physical address
 413  *
 414  * DESCRIPTION: search lower 1_mbyte of memory for the root system descriptor
 415  *              pointer structure.  If it is found, set *RSDP to point to it.
 416  *
 417  *              NOTE1: The RSDp must be either in the first 1_k of the Extended
 418  *              BIOS Data Area or between E0000 and FFFFF (From ACPI Spec.)
 419  *              Only a 32-bit physical address is necessary.
 420  *
 421  *              NOTE2: This function is always available, regardless of the
 422  *              initialization state of the rest of ACPI.
 423  *
 424  ******************************************************************************/
 425
 426 acpi_status
 427 acpi_tb_find_rsdp (
 428         struct acpi_table_desc          *table_info,
 429         u32                             flags)
 430 {
 431         u8                              *table_ptr;
 432         u8                              *mem_rover;
 433         u32                             physical_address;
 434         acpi_status                     status;
 435
 436
 437         ACPI_FUNCTION_TRACE ("tb_find_rsdp");
 438
 439
 440         /*
 441          * Scan supports either 1) Logical addressing or 2) Physical addressing
 442          */
 443         if ((flags & ACPI_MEMORY_MODE) == ACPI_LOGICAL_ADDRESSING) {
 444                 /*
 445                  * 1a) Get the location of the EBDA
 446                  */
 447                 status = acpi_os_map_memory ((acpi_physical_address) ACPI_EBDA_PTR_LOCATION,
 448                                   ACPI_EBDA_PTR_LENGTH,
 449                                   (void *) &table_ptr);
 450                 if (ACPI_FAILURE (status)) {
 451                         ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Could not map memory at %8.8X for length %X\n",
 452                                 ACPI_EBDA_PTR_LOCATION, ACPI_EBDA_PTR_LENGTH));
 453                         return_ACPI_STATUS (status);
 454                 }
 455
 456                 ACPI_MOVE_16_TO_32 (&physical_address, table_ptr);
 457                 physical_address <<= 4;                 /* Convert segment to physical address */
 458                 acpi_os_unmap_memory (table_ptr, ACPI_EBDA_PTR_LENGTH);
 459
 460                 /* EBDA present? */
 461
 462                 if (physical_address > 0x400) {
 463                         /*
 464                          * 1b) Search EBDA paragraphs (EBDa is required to be a minimum of 1_k length)
 465                          */
 466                         status = acpi_os_map_memory ((acpi_physical_address) physical_address,
 467                                           ACPI_EBDA_WINDOW_SIZE,
 468                                           (void *) &table_ptr);
 469                         if (ACPI_FAILURE (status)) {
 470                                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Could not map memory at %8.8X for length %X\n",
 471                                         physical_address, ACPI_EBDA_WINDOW_SIZE));
 472                                 return_ACPI_STATUS (status);
 473                         }
 474
 475                         mem_rover = acpi_tb_scan_memory_for_rsdp (table_ptr, ACPI_EBDA_WINDOW_SIZE);
 476                         acpi_os_unmap_memory (table_ptr, ACPI_EBDA_WINDOW_SIZE);
 477
 478                         if (mem_rover) {
 479                                 /* Found it, return the physical address */
 480
 481                                 physical_address += ACPI_PTR_DIFF (mem_rover, table_ptr);
 482
 483                                 table_info->physical_address = (acpi_physical_address) physical_address;
 484                                 return_ACPI_STATUS (AE_OK);
 485                         }
 486                 }
 487
 488                 /*
 489                  * 2) Search upper memory: 16-byte boundaries in E0000h-FFFFFh
 490                  */
 491                 status = acpi_os_map_memory ((acpi_physical_address) ACPI_HI_RSDP_WINDOW_BASE,
 492                                   ACPI_HI_RSDP_WINDOW_SIZE,
 493                                   (void *) &table_ptr);
 494                 if (ACPI_FAILURE (status)) {
 495                         ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Could not map memory at %8.8X for length %X\n",
 496                                 ACPI_HI_RSDP_WINDOW_BASE, ACPI_HI_RSDP_WINDOW_SIZE));
 497                         return_ACPI_STATUS (status);
 498                 }
 499
 500                 mem_rover = acpi_tb_scan_memory_for_rsdp (table_ptr, ACPI_HI_RSDP_WINDOW_SIZE);
 501                 acpi_os_unmap_memory (table_ptr, ACPI_HI_RSDP_WINDOW_SIZE);
 502
 503                 if (mem_rover) {
 504                         /* Found it, return the physical address */
 505
 506                         physical_address = ACPI_HI_RSDP_WINDOW_BASE + ACPI_PTR_DIFF (mem_rover, table_ptr);
 507
 508                         table_info->physical_address = (acpi_physical_address) physical_address;
 509                         return_ACPI_STATUS (AE_OK);
 510                 }
 511         }
 512
 513         /*
 514          * Physical addressing
 515          */
 516         else {
 517                 /*
 518                  * 1a) Get the location of the EBDA
 519                  */
 520                 ACPI_MOVE_16_TO_32 (&physical_address, ACPI_EBDA_PTR_LOCATION);
 521                 physical_address <<= 4;     /* Convert segment to physical address */
 522
 523                 /* EBDA present? */
 524
 525                 if (physical_address > 0x400) {
 526                         /*
 527                          * 1b) Search EBDA paragraphs (EBDa is required to be a minimum of 1_k length)
 528                          */
 529                         mem_rover = acpi_tb_scan_memory_for_rsdp (ACPI_PHYSADDR_TO_PTR (physical_address),
 530                                           ACPI_EBDA_WINDOW_SIZE);
 531                         if (mem_rover) {
 532                                 /* Found it, return the physical address */
 533
 534                                 table_info->physical_address = ACPI_TO_INTEGER (mem_rover);
 535                                 return_ACPI_STATUS (AE_OK);
 536                         }
 537                 }
 538
 539                 /*
 540                  * 2) Search upper memory: 16-byte boundaries in E0000h-FFFFFh
 541                  */
 542                 mem_rover = acpi_tb_scan_memory_for_rsdp (ACPI_PHYSADDR_TO_PTR (ACPI_HI_RSDP_WINDOW_BASE),
 543                                   ACPI_HI_RSDP_WINDOW_SIZE);
 544                 if (mem_rover) {
 545                         /* Found it, return the physical address */
 546
 547                         table_info->physical_address = ACPI_TO_INTEGER (mem_rover);
 548                         return_ACPI_STATUS (AE_OK);
 549                 }
 550         }
 551
 552         /* RSDP signature was not found */
 553
 554         return_ACPI_STATUS (AE_NOT_FOUND);
 555 }
 556
 557 #endif
 558