git.oblomov.eu Git - linux-2.6/blob - drivers/acpi/tables/tbutils.c

   1 /******************************************************************************
   2  *
   3  * Module Name: tbutils   - table utilities
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2008, Intel Corp.
   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/actables.h>
  46
  47 #define _COMPONENT          ACPI_TABLES
  48 ACPI_MODULE_NAME("tbutils")
  49
  50 /* Local prototypes */
  51 static acpi_physical_address
  52 acpi_tb_get_root_table_entry(u8 *table_entry, u32 table_entry_size);
  53
  54 /*******************************************************************************
  55  *
  56  * FUNCTION:    acpi_tb_check_xsdt
  57  *
  58  * PARAMETERS:  address                    - Pointer to the XSDT
  59  *
  60  * RETURN:      status
  61  *              AE_OK - XSDT is okay
  62  *              AE_NO_MEMORY - can't map XSDT
  63  *              AE_INVALID_TABLE_LENGTH - invalid table length
  64  *              AE_NULL_ENTRY - XSDT has NULL entry
  65  *
  66  * DESCRIPTION: validate XSDT
  67 ******************************************************************************/
  68
  69 static acpi_status
  70 acpi_tb_check_xsdt(acpi_physical_address address)
  71 {
  72         struct acpi_table_header *table;
  73         u32 length;
  74         u64 xsdt_entry_address;
  75         u8 *table_entry;
  76         u32 table_count;
  77         int i;
  78
  79         table = acpi_os_map_memory(address, sizeof(struct acpi_table_header));
  80         if (!table)
  81                 return AE_NO_MEMORY;
  82
  83         length = table->length;
  84         acpi_os_unmap_memory(table, sizeof(struct acpi_table_header));
  85         if (length < sizeof(struct acpi_table_header))
  86                 return AE_INVALID_TABLE_LENGTH;
  87
  88         table = acpi_os_map_memory(address, length);
  89         if (!table)
  90                 return AE_NO_MEMORY;
  91
  92         /* Calculate the number of tables described in XSDT */
  93         table_count =
  94                 (u32) ((table->length -
  95                 sizeof(struct acpi_table_header)) / sizeof(u64));
  96         table_entry =
  97                 ACPI_CAST_PTR(u8, table) + sizeof(struct acpi_table_header);
  98         for (i = 0; i < table_count; i++) {
  99                 ACPI_MOVE_64_TO_64(&xsdt_entry_address, table_entry);
 100                 if (!xsdt_entry_address) {
 101                         /* XSDT has NULL entry */
 102                         break;
 103                 }
 104                 table_entry += sizeof(u64);
 105         }
 106         acpi_os_unmap_memory(table, length);
 107
 108         if (i < table_count)
 109                 return AE_NULL_ENTRY;
 110         else
 111                 return AE_OK;
 112 }
 113
 114 /*******************************************************************************
 115  *
 116  * FUNCTION:    acpi_tb_tables_loaded
 117  *
 118  * PARAMETERS:  None
 119  *
 120  * RETURN:      TRUE if required ACPI tables are loaded
 121  *
 122  * DESCRIPTION: Determine if the minimum required ACPI tables are present
 123  *              (FADT, FACS, DSDT)
 124  *
 125  ******************************************************************************/
 126
 127 u8 acpi_tb_tables_loaded(void)
 128 {
 129
 130         if (acpi_gbl_root_table_list.count >= 3) {
 131                 return (TRUE);
 132         }
 133
 134         return (FALSE);
 135 }
 136
 137 /*******************************************************************************
 138  *
 139  * FUNCTION:    acpi_tb_print_table_header
 140  *
 141  * PARAMETERS:  Address             - Table physical address
 142  *              Header              - Table header
 143  *
 144  * RETURN:      None
 145  *
 146  * DESCRIPTION: Print an ACPI table header. Special cases for FACS and RSDP.
 147  *
 148  ******************************************************************************/
 149
 150 void
 151 acpi_tb_print_table_header(acpi_physical_address address,
 152                            struct acpi_table_header *header)
 153 {
 154
 155         if (ACPI_COMPARE_NAME(header->signature, ACPI_SIG_FACS)) {
 156
 157                 /* FACS only has signature and length fields of common table header */
 158
 159                 ACPI_INFO((AE_INFO, "%4.4s %08lX, %04X",
 160                            header->signature, (unsigned long)address,
 161                            header->length));
 162         } else if (ACPI_COMPARE_NAME(header->signature, ACPI_SIG_RSDP)) {
 163
 164                 /* RSDP has no common fields */
 165
 166                 ACPI_INFO((AE_INFO, "RSDP %08lX, %04X (r%d %6.6s)",
 167                            (unsigned long)address,
 168                            (ACPI_CAST_PTR(struct acpi_table_rsdp, header)->
 169                             revision >
 170                             0) ? ACPI_CAST_PTR(struct acpi_table_rsdp,
 171                                                header)->length : 20,
 172                            ACPI_CAST_PTR(struct acpi_table_rsdp,
 173                                          header)->revision,
 174                            ACPI_CAST_PTR(struct acpi_table_rsdp,
 175                                          header)->oem_id));
 176         } else {
 177                 /* Standard ACPI table with full common header */
 178
 179                 ACPI_INFO((AE_INFO,
 180                            "%4.4s %08lX, %04X (r%d %6.6s %8.8s %8X %4.4s %8X)",
 181                            header->signature, (unsigned long)address,
 182                            header->length, header->revision, header->oem_id,
 183                            header->oem_table_id, header->oem_revision,
 184                            header->asl_compiler_id,
 185                            header->asl_compiler_revision));
 186         }
 187 }
 188
 189 /*******************************************************************************
 190  *
 191  * FUNCTION:    acpi_tb_validate_checksum
 192  *
 193  * PARAMETERS:  Table               - ACPI table to verify
 194  *              Length              - Length of entire table
 195  *
 196  * RETURN:      Status
 197  *
 198  * DESCRIPTION: Verifies that the table checksums to zero. Optionally returns
 199  *              exception on bad checksum.
 200  *
 201  ******************************************************************************/
 202
 203 acpi_status acpi_tb_verify_checksum(struct acpi_table_header *table, u32 length)
 204 {
 205         u8 checksum;
 206
 207         /* Compute the checksum on the table */
 208
 209         checksum = acpi_tb_checksum(ACPI_CAST_PTR(u8, table), length);
 210
 211         /* Checksum ok? (should be zero) */
 212
 213         if (checksum) {
 214                 ACPI_WARNING((AE_INFO,
 215                               "Incorrect checksum in table [%4.4s] - %2.2X, should be %2.2X",
 216                               table->signature, table->checksum,
 217                               (u8) (table->checksum - checksum)));
 218
 219 #if (ACPI_CHECKSUM_ABORT)
 220
 221                 return (AE_BAD_CHECKSUM);
 222 #endif
 223         }
 224
 225         return (AE_OK);
 226 }
 227
 228 /*******************************************************************************
 229  *
 230  * FUNCTION:    acpi_tb_checksum
 231  *
 232  * PARAMETERS:  Buffer          - Pointer to memory region to be checked
 233  *              Length          - Length of this memory region
 234  *
 235  * RETURN:      Checksum (u8)
 236  *
 237  * DESCRIPTION: Calculates circular checksum of memory region.
 238  *
 239  ******************************************************************************/
 240
 241 u8 acpi_tb_checksum(u8 *buffer, u32 length)
 242 {
 243         u8 sum = 0;
 244         u8 *end = buffer + length;
 245
 246         while (buffer < end) {
 247                 sum = (u8) (sum + *(buffer++));
 248         }
 249
 250         return sum;
 251 }
 252
 253 /*******************************************************************************
 254  *
 255  * FUNCTION:    acpi_tb_install_table
 256  *
 257  * PARAMETERS:  Address                 - Physical address of DSDT or FACS
 258  *              Flags                   - Flags
 259  *              Signature               - Table signature, NULL if no need to
 260  *                                        match
 261  *              table_index             - Index into root table array
 262  *
 263  * RETURN:      None
 264  *
 265  * DESCRIPTION: Install an ACPI table into the global data structure.
 266  *
 267  ******************************************************************************/
 268
 269 void
 270 acpi_tb_install_table(acpi_physical_address address,
 271                       u8 flags, char *signature, u32 table_index)
 272 {
 273         struct acpi_table_header *table;
 274
 275         if (!address) {
 276                 ACPI_ERROR((AE_INFO,
 277                             "Null physical address for ACPI table [%s]",
 278                             signature));
 279                 return;
 280         }
 281
 282         /* Map just the table header */
 283
 284         table = acpi_os_map_memory(address, sizeof(struct acpi_table_header));
 285         if (!table) {
 286                 return;
 287         }
 288
 289         /* If a particular signature is expected, signature must match */
 290
 291         if (signature && !ACPI_COMPARE_NAME(table->signature, signature)) {
 292                 ACPI_ERROR((AE_INFO,
 293                             "Invalid signature 0x%X for ACPI table [%s]",
 294                             *ACPI_CAST_PTR(u32, table->signature), signature));
 295                 goto unmap_and_exit;
 296         }
 297
 298         /* Initialize the table entry */
 299
 300         acpi_gbl_root_table_list.tables[table_index].address = address;
 301         acpi_gbl_root_table_list.tables[table_index].length = table->length;
 302         acpi_gbl_root_table_list.tables[table_index].flags = flags;
 303
 304         ACPI_MOVE_32_TO_32(&
 305                            (acpi_gbl_root_table_list.tables[table_index].
 306                             signature), table->signature);
 307
 308         acpi_tb_print_table_header(address, table);
 309
 310         if (table_index == ACPI_TABLE_INDEX_DSDT) {
 311
 312                 /* Global integer width is based upon revision of the DSDT */
 313
 314                 acpi_ut_set_integer_width(table->revision);
 315         }
 316
 317       unmap_and_exit:
 318         acpi_os_unmap_memory(table, sizeof(struct acpi_table_header));
 319 }
 320
 321 /*******************************************************************************
 322  *
 323  * FUNCTION:    acpi_tb_get_root_table_entry
 324  *
 325  * PARAMETERS:  table_entry         - Pointer to the RSDT/XSDT table entry
 326  *              table_entry_size    - sizeof 32 or 64 (RSDT or XSDT)
 327  *
 328  * RETURN:      Physical address extracted from the root table
 329  *
 330  * DESCRIPTION: Get one root table entry. Handles 32-bit and 64-bit cases on
 331  *              both 32-bit and 64-bit platforms
 332  *
 333  * NOTE:        acpi_physical_address is 32-bit on 32-bit platforms, 64-bit on
 334  *              64-bit platforms.
 335  *
 336  ******************************************************************************/
 337
 338 static acpi_physical_address
 339 acpi_tb_get_root_table_entry(u8 *table_entry, u32 table_entry_size)
 340 {
 341         u64 address64;
 342
 343         /*
 344          * Get the table physical address (32-bit for RSDT, 64-bit for XSDT):
 345          * Note: Addresses are 32-bit aligned (not 64) in both RSDT and XSDT
 346          */
 347         if (table_entry_size == sizeof(u32)) {
 348                 /*
 349                  * 32-bit platform, RSDT: Return 32-bit table entry
 350                  * 64-bit platform, RSDT: Expand 32-bit to 64-bit and return
 351                  */
 352                 return ((acpi_physical_address)
 353                         (*ACPI_CAST_PTR(u32, table_entry)));
 354         } else {
 355                 /*
 356                  * 32-bit platform, XSDT: Truncate 64-bit to 32-bit and return
 357                  * 64-bit platform, XSDT: Move (unaligned) 64-bit to local, return 64-bit
 358                  */
 359                 ACPI_MOVE_64_TO_64(&address64, table_entry);
 360
 361 #if ACPI_MACHINE_WIDTH == 32
 362                 if (address64 > ACPI_UINT32_MAX) {
 363
 364                         /* Will truncate 64-bit address to 32 bits, issue warning */
 365
 366                         ACPI_WARNING((AE_INFO,
 367                                       "64-bit Physical Address in XSDT is too large (%8.8X%8.8X), truncating",
 368                                       ACPI_FORMAT_UINT64(address64)));
 369                 }
 370 #endif
 371                 return ((acpi_physical_address) (address64));
 372         }
 373 }
 374
 375 /*******************************************************************************
 376  *
 377  * FUNCTION:    acpi_tb_parse_root_table
 378  *
 379  * PARAMETERS:  Rsdp                    - Pointer to the RSDP
 380  *              Flags                   - Flags
 381  *
 382  * RETURN:      Status
 383  *
 384  * DESCRIPTION: This function is called to parse the Root System Description
 385  *              Table (RSDT or XSDT)
 386  *
 387  * NOTE:        Tables are mapped (not copied) for efficiency. The FACS must
 388  *              be mapped and cannot be copied because it contains the actual
 389  *              memory location of the ACPI Global Lock.
 390  *
 391  ******************************************************************************/
 392
 393 acpi_status __init
 394 acpi_tb_parse_root_table(acpi_physical_address rsdp_address, u8 flags)
 395 {
 396         struct acpi_table_rsdp *rsdp;
 397         u32 table_entry_size;
 398         u32 i;
 399         u32 table_count;
 400         struct acpi_table_header *table;
 401         acpi_physical_address address;
 402         acpi_physical_address uninitialized_var(rsdt_address);
 403         u32 length;
 404         u8 *table_entry;
 405         acpi_status status;
 406
 407         ACPI_FUNCTION_TRACE(tb_parse_root_table);
 408
 409         /*
 410          * Map the entire RSDP and extract the address of the RSDT or XSDT
 411          */
 412         rsdp = acpi_os_map_memory(rsdp_address, sizeof(struct acpi_table_rsdp));
 413         if (!rsdp) {
 414                 return_ACPI_STATUS(AE_NO_MEMORY);
 415         }
 416
 417         acpi_tb_print_table_header(rsdp_address,
 418                                    ACPI_CAST_PTR(struct acpi_table_header,
 419                                                  rsdp));
 420
 421         /* Differentiate between RSDT and XSDT root tables */
 422
 423         if (rsdp->revision > 1 && rsdp->xsdt_physical_address) {
 424                 /*
 425                  * Root table is an XSDT (64-bit physical addresses). We must use the
 426                  * XSDT if the revision is > 1 and the XSDT pointer is present, as per
 427                  * the ACPI specification.
 428                  */
 429                 address = (acpi_physical_address) rsdp->xsdt_physical_address;
 430                 table_entry_size = sizeof(u64);
 431                 rsdt_address = (acpi_physical_address)
 432                                         rsdp->rsdt_physical_address;
 433         } else {
 434                 /* Root table is an RSDT (32-bit physical addresses) */
 435
 436                 address = (acpi_physical_address) rsdp->rsdt_physical_address;
 437                 table_entry_size = sizeof(u32);
 438         }
 439
 440         /*
 441          * It is not possible to map more than one entry in some environments,
 442          * so unmap the RSDP here before mapping other tables
 443          */
 444         acpi_os_unmap_memory(rsdp, sizeof(struct acpi_table_rsdp));
 445
 446         if (table_entry_size == sizeof(u64)) {
 447                 if (acpi_tb_check_xsdt(address) == AE_NULL_ENTRY) {
 448                         /* XSDT has NULL entry, RSDT is used */
 449                         address = rsdt_address;
 450                         table_entry_size = sizeof(u32);
 451                         ACPI_WARNING((AE_INFO, "BIOS XSDT has NULL entry, "
 452                                         "using RSDT"));
 453                 }
 454         }
 455         /* Map the RSDT/XSDT table header to get the full table length */
 456
 457         table = acpi_os_map_memory(address, sizeof(struct acpi_table_header));
 458         if (!table) {
 459                 return_ACPI_STATUS(AE_NO_MEMORY);
 460         }
 461
 462         acpi_tb_print_table_header(address, table);
 463
 464         /* Get the length of the full table, verify length and map entire table */
 465
 466         length = table->length;
 467         acpi_os_unmap_memory(table, sizeof(struct acpi_table_header));
 468
 469         if (length < sizeof(struct acpi_table_header)) {
 470                 ACPI_ERROR((AE_INFO, "Invalid length 0x%X in RSDT/XSDT",
 471                             length));
 472                 return_ACPI_STATUS(AE_INVALID_TABLE_LENGTH);
 473         }
 474
 475         table = acpi_os_map_memory(address, length);
 476         if (!table) {
 477                 return_ACPI_STATUS(AE_NO_MEMORY);
 478         }
 479
 480         /* Validate the root table checksum */
 481
 482         status = acpi_tb_verify_checksum(table, length);
 483         if (ACPI_FAILURE(status)) {
 484                 acpi_os_unmap_memory(table, length);
 485                 return_ACPI_STATUS(status);
 486         }
 487
 488         /* Calculate the number of tables described in the root table */
 489
 490         table_count =
 491             (u32) ((table->length -
 492                     sizeof(struct acpi_table_header)) / table_entry_size);
 493
 494         /*
 495          * First two entries in the table array are reserved for the DSDT and FACS,
 496          * which are not actually present in the RSDT/XSDT - they come from the FADT
 497          */
 498         table_entry =
 499             ACPI_CAST_PTR(u8, table) + sizeof(struct acpi_table_header);
 500         acpi_gbl_root_table_list.count = 2;
 501
 502         /*
 503          * Initialize the root table array from the RSDT/XSDT
 504          */
 505         for (i = 0; i < table_count; i++) {
 506                 if (acpi_gbl_root_table_list.count >=
 507                     acpi_gbl_root_table_list.size) {
 508
 509                         /* There is no more room in the root table array, attempt resize */
 510
 511                         status = acpi_tb_resize_root_table_list();
 512                         if (ACPI_FAILURE(status)) {
 513                                 ACPI_WARNING((AE_INFO,
 514                                               "Truncating %u table entries!",
 515                                               (unsigned)
 516                                               (acpi_gbl_root_table_list.size -
 517                                                acpi_gbl_root_table_list.
 518                                                count)));
 519                                 break;
 520                         }
 521                 }
 522
 523                 /* Get the table physical address (32-bit for RSDT, 64-bit for XSDT) */
 524
 525                 acpi_gbl_root_table_list.tables[acpi_gbl_root_table_list.count].
 526                     address =
 527                     acpi_tb_get_root_table_entry(table_entry, table_entry_size);
 528
 529                 table_entry += table_entry_size;
 530                 acpi_gbl_root_table_list.count++;
 531         }
 532
 533         /*
 534          * It is not possible to map more than one entry in some environments,
 535          * so unmap the root table here before mapping other tables
 536          */
 537         acpi_os_unmap_memory(table, length);
 538
 539         /*
 540          * Complete the initialization of the root table array by examining
 541          * the header of each table
 542          */
 543         for (i = 2; i < acpi_gbl_root_table_list.count; i++) {
 544                 acpi_tb_install_table(acpi_gbl_root_table_list.tables[i].
 545                                       address, flags, NULL, i);
 546
 547                 /* Special case for FADT - get the DSDT and FACS */
 548
 549                 if (ACPI_COMPARE_NAME
 550                     (&acpi_gbl_root_table_list.tables[i].signature,
 551                      ACPI_SIG_FADT)) {
 552                         acpi_tb_parse_fadt(i, flags);
 553                 }
 554         }
 555
 556         return_ACPI_STATUS(AE_OK);
 557 }