1 /****************************************************************************** 2 * 3 * Module Name: tbutils - table utilities 4 * 5 *****************************************************************************/ 6 7 /* 8 * Copyright (C) 2000 - 2012, 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 "accommon.h" 46 #include "actables.h" 47 48 #define _COMPONENT ACPI_TABLES 49 ACPI_MODULE_NAME("tbutils") 50 51 /* Local prototypes */ 52 static void acpi_tb_fix_string(char *string, acpi_size length); 53 54 static void 55 acpi_tb_cleanup_table_header(struct acpi_table_header *out_header, 56 struct acpi_table_header *header); 57 58 static acpi_physical_address 59 acpi_tb_get_root_table_entry(u8 *table_entry, u32 table_entry_size); 60 61 /******************************************************************************* 62 * 63 * FUNCTION: acpi_tb_check_xsdt 64 * 65 * PARAMETERS: address - Pointer to the XSDT 66 * 67 * RETURN: status 68 * AE_OK - XSDT is okay 69 * AE_NO_MEMORY - can't map XSDT 70 * AE_INVALID_TABLE_LENGTH - invalid table length 71 * AE_NULL_ENTRY - XSDT has NULL entry 72 * 73 * DESCRIPTION: validate XSDT 74 ******************************************************************************/ 75 76 static acpi_status 77 acpi_tb_check_xsdt(acpi_physical_address address) 78 { 79 struct acpi_table_header *table; 80 u32 length; 81 u64 xsdt_entry_address; 82 u8 *table_entry; 83 u32 table_count; 84 int i; 85 86 table = acpi_os_map_memory(address, sizeof(struct acpi_table_header)); 87 if (!table) 88 return AE_NO_MEMORY; 89 90 length = table->length; 91 acpi_os_unmap_memory(table, sizeof(struct acpi_table_header)); 92 if (length < sizeof(struct acpi_table_header)) 93 return AE_INVALID_TABLE_LENGTH; 94 95 table = acpi_os_map_memory(address, length); 96 if (!table) 97 return AE_NO_MEMORY; 98 99 /* Calculate the number of tables described in XSDT */ 100 table_count = 101 (u32) ((table->length - 102 sizeof(struct acpi_table_header)) / sizeof(u64)); 103 table_entry = 104 ACPI_CAST_PTR(u8, table) + sizeof(struct acpi_table_header); 105 for (i = 0; i < table_count; i++) { 106 ACPI_MOVE_64_TO_64(&xsdt_entry_address, table_entry); 107 if (!xsdt_entry_address) { 108 /* XSDT has NULL entry */ 109 break; 110 } 111 table_entry += sizeof(u64); 112 } 113 acpi_os_unmap_memory(table, length); 114 115 if (i < table_count) 116 return AE_NULL_ENTRY; 117 else 118 return AE_OK; 119 } 120 121 /******************************************************************************* 122 * 123 * FUNCTION: acpi_tb_initialize_facs 124 * 125 * PARAMETERS: None 126 * 127 * RETURN: Status 128 * 129 * DESCRIPTION: Create a permanent mapping for the FADT and save it in a global 130 * for accessing the Global Lock and Firmware Waking Vector 131 * 132 ******************************************************************************/ 133 134 acpi_status acpi_tb_initialize_facs(void) 135 { 136 acpi_status status; 137 138 /* If Hardware Reduced flag is set, there is no FACS */ 139 140 if (acpi_gbl_reduced_hardware) { 141 acpi_gbl_FACS = NULL; 142 return (AE_OK); 143 } 144 145 status = acpi_get_table_by_index(ACPI_TABLE_INDEX_FACS, 146 ACPI_CAST_INDIRECT_PTR(struct 147 acpi_table_header, 148 &acpi_gbl_FACS)); 149 return status; 150 } 151 152 /******************************************************************************* 153 * 154 * FUNCTION: acpi_tb_tables_loaded 155 * 156 * PARAMETERS: None 157 * 158 * RETURN: TRUE if required ACPI tables are loaded 159 * 160 * DESCRIPTION: Determine if the minimum required ACPI tables are present 161 * (FADT, FACS, DSDT) 162 * 163 ******************************************************************************/ 164 165 u8 acpi_tb_tables_loaded(void) 166 { 167 168 if (acpi_gbl_root_table_list.current_table_count >= 3) { 169 return (TRUE); 170 } 171 172 return (FALSE); 173 } 174 175 /******************************************************************************* 176 * 177 * FUNCTION: acpi_tb_fix_string 178 * 179 * PARAMETERS: String - String to be repaired 180 * Length - Maximum length 181 * 182 * RETURN: None 183 * 184 * DESCRIPTION: Replace every non-printable or non-ascii byte in the string 185 * with a question mark '?'. 186 * 187 ******************************************************************************/ 188 189 static void acpi_tb_fix_string(char *string, acpi_size length) 190 { 191 192 while (length && *string) { 193 if (!ACPI_IS_PRINT(*string)) { 194 *string = '?'; 195 } 196 string++; 197 length--; 198 } 199 } 200 201 /******************************************************************************* 202 * 203 * FUNCTION: acpi_tb_cleanup_table_header 204 * 205 * PARAMETERS: out_header - Where the cleaned header is returned 206 * Header - Input ACPI table header 207 * 208 * RETURN: Returns the cleaned header in out_header 209 * 210 * DESCRIPTION: Copy the table header and ensure that all "string" fields in 211 * the header consist of printable characters. 212 * 213 ******************************************************************************/ 214 215 static void 216 acpi_tb_cleanup_table_header(struct acpi_table_header *out_header, 217 struct acpi_table_header *header) 218 { 219 220 ACPI_MEMCPY(out_header, header, sizeof(struct acpi_table_header)); 221 222 acpi_tb_fix_string(out_header->signature, ACPI_NAME_SIZE); 223 acpi_tb_fix_string(out_header->oem_id, ACPI_OEM_ID_SIZE); 224 acpi_tb_fix_string(out_header->oem_table_id, ACPI_OEM_TABLE_ID_SIZE); 225 acpi_tb_fix_string(out_header->asl_compiler_id, ACPI_NAME_SIZE); 226 } 227 228 /******************************************************************************* 229 * 230 * FUNCTION: acpi_tb_print_table_header 231 * 232 * PARAMETERS: Address - Table physical address 233 * Header - Table header 234 * 235 * RETURN: None 236 * 237 * DESCRIPTION: Print an ACPI table header. Special cases for FACS and RSDP. 238 * 239 ******************************************************************************/ 240 241 void 242 acpi_tb_print_table_header(acpi_physical_address address, 243 struct acpi_table_header *header) 244 { 245 struct acpi_table_header local_header; 246 247 /* 248 * The reason that the Address is cast to a void pointer is so that we 249 * can use %p which will work properly on both 32-bit and 64-bit hosts. 250 */ 251 if (ACPI_COMPARE_NAME(header->signature, ACPI_SIG_FACS)) { 252 253 /* FACS only has signature and length fields */ 254 255 ACPI_INFO((AE_INFO, "%4.4s %p %05X", 256 header->signature, ACPI_CAST_PTR(void, address), 257 header->length)); 258 } else if (ACPI_COMPARE_NAME(header->signature, ACPI_SIG_RSDP)) { 259 260 /* RSDP has no common fields */ 261 262 ACPI_MEMCPY(local_header.oem_id, 263 ACPI_CAST_PTR(struct acpi_table_rsdp, 264 header)->oem_id, ACPI_OEM_ID_SIZE); 265 acpi_tb_fix_string(local_header.oem_id, ACPI_OEM_ID_SIZE); 266 267 ACPI_INFO((AE_INFO, "RSDP %p %05X (v%.2d %6.6s)", 268 ACPI_CAST_PTR (void, address), 269 (ACPI_CAST_PTR(struct acpi_table_rsdp, header)-> 270 revision > 271 0) ? ACPI_CAST_PTR(struct acpi_table_rsdp, 272 header)->length : 20, 273 ACPI_CAST_PTR(struct acpi_table_rsdp, 274 header)->revision, 275 local_header.oem_id)); 276 } else { 277 /* Standard ACPI table with full common header */ 278 279 acpi_tb_cleanup_table_header(&local_header, header); 280 281 ACPI_INFO((AE_INFO, 282 "%4.4s %p %05X (v%.2d %6.6s %8.8s %08X %4.4s %08X)", 283 local_header.signature, ACPI_CAST_PTR(void, address), 284 local_header.length, local_header.revision, 285 local_header.oem_id, local_header.oem_table_id, 286 local_header.oem_revision, 287 local_header.asl_compiler_id, 288 local_header.asl_compiler_revision)); 289 290 } 291 } 292 293 /******************************************************************************* 294 * 295 * FUNCTION: acpi_tb_validate_checksum 296 * 297 * PARAMETERS: Table - ACPI table to verify 298 * Length - Length of entire table 299 * 300 * RETURN: Status 301 * 302 * DESCRIPTION: Verifies that the table checksums to zero. Optionally returns 303 * exception on bad checksum. 304 * 305 ******************************************************************************/ 306 307 acpi_status acpi_tb_verify_checksum(struct acpi_table_header *table, u32 length) 308 { 309 u8 checksum; 310 311 /* Compute the checksum on the table */ 312 313 checksum = acpi_tb_checksum(ACPI_CAST_PTR(u8, table), length); 314 315 /* Checksum ok? (should be zero) */ 316 317 if (checksum) { 318 ACPI_WARNING((AE_INFO, 319 "Incorrect checksum in table [%4.4s] - 0x%2.2X, should be 0x%2.2X", 320 table->signature, table->checksum, 321 (u8) (table->checksum - checksum))); 322 323 #if (ACPI_CHECKSUM_ABORT) 324 325 return (AE_BAD_CHECKSUM); 326 #endif 327 } 328 329 return (AE_OK); 330 } 331 332 /******************************************************************************* 333 * 334 * FUNCTION: acpi_tb_checksum 335 * 336 * PARAMETERS: Buffer - Pointer to memory region to be checked 337 * Length - Length of this memory region 338 * 339 * RETURN: Checksum (u8) 340 * 341 * DESCRIPTION: Calculates circular checksum of memory region. 342 * 343 ******************************************************************************/ 344 345 u8 acpi_tb_checksum(u8 *buffer, u32 length) 346 { 347 u8 sum = 0; 348 u8 *end = buffer + length; 349 350 while (buffer < end) { 351 sum = (u8) (sum + *(buffer++)); 352 } 353 354 return sum; 355 } 356 357 /******************************************************************************* 358 * 359 * FUNCTION: acpi_tb_check_dsdt_header 360 * 361 * PARAMETERS: None 362 * 363 * RETURN: None 364 * 365 * DESCRIPTION: Quick compare to check validity of the DSDT. This will detect 366 * if the DSDT has been replaced from outside the OS and/or if 367 * the DSDT header has been corrupted. 368 * 369 ******************************************************************************/ 370 371 void acpi_tb_check_dsdt_header(void) 372 { 373 374 /* Compare original length and checksum to current values */ 375 376 if (acpi_gbl_original_dsdt_header.length != acpi_gbl_DSDT->length || 377 acpi_gbl_original_dsdt_header.checksum != acpi_gbl_DSDT->checksum) { 378 ACPI_ERROR((AE_INFO, 379 "The DSDT has been corrupted or replaced - old, new headers below")); 380 acpi_tb_print_table_header(0, &acpi_gbl_original_dsdt_header); 381 acpi_tb_print_table_header(0, acpi_gbl_DSDT); 382 383 ACPI_ERROR((AE_INFO, 384 "Please send DMI info to linux-acpi@vger.kernel.org\n" 385 "If system does not work as expected, please boot with acpi=copy_dsdt")); 386 387 /* Disable further error messages */ 388 389 acpi_gbl_original_dsdt_header.length = acpi_gbl_DSDT->length; 390 acpi_gbl_original_dsdt_header.checksum = 391 acpi_gbl_DSDT->checksum; 392 } 393 } 394 395 /******************************************************************************* 396 * 397 * FUNCTION: acpi_tb_copy_dsdt 398 * 399 * PARAMETERS: table_desc - Installed table to copy 400 * 401 * RETURN: None 402 * 403 * DESCRIPTION: Implements a subsystem option to copy the DSDT to local memory. 404 * Some very bad BIOSs are known to either corrupt the DSDT or 405 * install a new, bad DSDT. This copy works around the problem. 406 * 407 ******************************************************************************/ 408 409 struct acpi_table_header *acpi_tb_copy_dsdt(u32 table_index) 410 { 411 struct acpi_table_header *new_table; 412 struct acpi_table_desc *table_desc; 413 414 table_desc = &acpi_gbl_root_table_list.tables[table_index]; 415 416 new_table = ACPI_ALLOCATE(table_desc->length); 417 if (!new_table) { 418 ACPI_ERROR((AE_INFO, "Could not copy DSDT of length 0x%X", 419 table_desc->length)); 420 return (NULL); 421 } 422 423 ACPI_MEMCPY(new_table, table_desc->pointer, table_desc->length); 424 acpi_tb_delete_table(table_desc); 425 table_desc->pointer = new_table; 426 table_desc->flags = ACPI_TABLE_ORIGIN_ALLOCATED; 427 428 ACPI_INFO((AE_INFO, 429 "Forced DSDT copy: length 0x%05X copied locally, original unmapped", 430 new_table->length)); 431 432 return (new_table); 433 } 434 435 /******************************************************************************* 436 * 437 * FUNCTION: acpi_tb_install_table 438 * 439 * PARAMETERS: Address - Physical address of DSDT or FACS 440 * Signature - Table signature, NULL if no need to 441 * match 442 * table_index - Index into root table array 443 * 444 * RETURN: None 445 * 446 * DESCRIPTION: Install an ACPI table into the global data structure. The 447 * table override mechanism is implemented here to allow the host 448 * OS to replace any table before it is installed in the root 449 * table array. 450 * 451 ******************************************************************************/ 452 453 void 454 acpi_tb_install_table(acpi_physical_address address, 455 char *signature, u32 table_index) 456 { 457 u8 flags; 458 acpi_status status; 459 struct acpi_table_header *table_to_install; 460 struct acpi_table_header *mapped_table; 461 struct acpi_table_header *override_table = NULL; 462 463 if (!address) { 464 ACPI_ERROR((AE_INFO, 465 "Null physical address for ACPI table [%s]", 466 signature)); 467 return; 468 } 469 470 /* Map just the table header */ 471 472 mapped_table = 473 acpi_os_map_memory(address, sizeof(struct acpi_table_header)); 474 if (!mapped_table) { 475 return; 476 } 477 478 /* If a particular signature is expected (DSDT/FACS), it must match */ 479 480 if (signature && !ACPI_COMPARE_NAME(mapped_table->signature, signature)) { 481 ACPI_ERROR((AE_INFO, 482 "Invalid signature 0x%X for ACPI table, expected [%s]", 483 *ACPI_CAST_PTR(u32, mapped_table->signature), 484 signature)); 485 goto unmap_and_exit; 486 } 487 488 /* 489 * ACPI Table Override: 490 * 491 * Before we install the table, let the host OS override it with a new 492 * one if desired. Any table within the RSDT/XSDT can be replaced, 493 * including the DSDT which is pointed to by the FADT. 494 */ 495 status = acpi_os_table_override(mapped_table, &override_table); 496 if (ACPI_SUCCESS(status) && override_table) { 497 ACPI_INFO((AE_INFO, 498 "%4.4s @ 0x%p Table override, replaced with:", 499 mapped_table->signature, ACPI_CAST_PTR(void, 500 address))); 501 502 acpi_gbl_root_table_list.tables[table_index].pointer = 503 override_table; 504 address = ACPI_PTR_TO_PHYSADDR(override_table); 505 506 table_to_install = override_table; 507 flags = ACPI_TABLE_ORIGIN_OVERRIDE; 508 } else { 509 table_to_install = mapped_table; 510 flags = ACPI_TABLE_ORIGIN_MAPPED; 511 } 512 513 /* Initialize the table entry */ 514 515 acpi_gbl_root_table_list.tables[table_index].address = address; 516 acpi_gbl_root_table_list.tables[table_index].length = 517 table_to_install->length; 518 acpi_gbl_root_table_list.tables[table_index].flags = flags; 519 520 ACPI_MOVE_32_TO_32(& 521 (acpi_gbl_root_table_list.tables[table_index]. 522 signature), table_to_install->signature); 523 524 acpi_tb_print_table_header(address, table_to_install); 525 526 if (table_index == ACPI_TABLE_INDEX_DSDT) { 527 528 /* Global integer width is based upon revision of the DSDT */ 529 530 acpi_ut_set_integer_width(table_to_install->revision); 531 } 532 533 unmap_and_exit: 534 acpi_os_unmap_memory(mapped_table, sizeof(struct acpi_table_header)); 535 } 536 537 /******************************************************************************* 538 * 539 * FUNCTION: acpi_tb_get_root_table_entry 540 * 541 * PARAMETERS: table_entry - Pointer to the RSDT/XSDT table entry 542 * table_entry_size - sizeof 32 or 64 (RSDT or XSDT) 543 * 544 * RETURN: Physical address extracted from the root table 545 * 546 * DESCRIPTION: Get one root table entry. Handles 32-bit and 64-bit cases on 547 * both 32-bit and 64-bit platforms 548 * 549 * NOTE: acpi_physical_address is 32-bit on 32-bit platforms, 64-bit on 550 * 64-bit platforms. 551 * 552 ******************************************************************************/ 553 554 static acpi_physical_address 555 acpi_tb_get_root_table_entry(u8 *table_entry, u32 table_entry_size) 556 { 557 u64 address64; 558 559 /* 560 * Get the table physical address (32-bit for RSDT, 64-bit for XSDT): 561 * Note: Addresses are 32-bit aligned (not 64) in both RSDT and XSDT 562 */ 563 if (table_entry_size == sizeof(u32)) { 564 /* 565 * 32-bit platform, RSDT: Return 32-bit table entry 566 * 64-bit platform, RSDT: Expand 32-bit to 64-bit and return 567 */ 568 return ((acpi_physical_address) 569 (*ACPI_CAST_PTR(u32, table_entry))); 570 } else { 571 /* 572 * 32-bit platform, XSDT: Truncate 64-bit to 32-bit and return 573 * 64-bit platform, XSDT: Move (unaligned) 64-bit to local, 574 * return 64-bit 575 */ 576 ACPI_MOVE_64_TO_64(&address64, table_entry); 577 578 #if ACPI_MACHINE_WIDTH == 32 579 if (address64 > ACPI_UINT32_MAX) { 580 581 /* Will truncate 64-bit address to 32 bits, issue warning */ 582 583 ACPI_WARNING((AE_INFO, 584 "64-bit Physical Address in XSDT is too large (0x%8.8X%8.8X)," 585 " truncating", 586 ACPI_FORMAT_UINT64(address64))); 587 } 588 #endif 589 return ((acpi_physical_address) (address64)); 590 } 591 } 592 593 /******************************************************************************* 594 * 595 * FUNCTION: acpi_tb_parse_root_table 596 * 597 * PARAMETERS: Rsdp - Pointer to the RSDP 598 * 599 * RETURN: Status 600 * 601 * DESCRIPTION: This function is called to parse the Root System Description 602 * Table (RSDT or XSDT) 603 * 604 * NOTE: Tables are mapped (not copied) for efficiency. The FACS must 605 * be mapped and cannot be copied because it contains the actual 606 * memory location of the ACPI Global Lock. 607 * 608 ******************************************************************************/ 609 610 acpi_status __init 611 acpi_tb_parse_root_table(acpi_physical_address rsdp_address) 612 { 613 struct acpi_table_rsdp *rsdp; 614 u32 table_entry_size; 615 u32 i; 616 u32 table_count; 617 struct acpi_table_header *table; 618 acpi_physical_address address; 619 acpi_physical_address uninitialized_var(rsdt_address); 620 u32 length; 621 u8 *table_entry; 622 acpi_status status; 623 624 ACPI_FUNCTION_TRACE(tb_parse_root_table); 625 626 /* 627 * Map the entire RSDP and extract the address of the RSDT or XSDT 628 */ 629 rsdp = acpi_os_map_memory(rsdp_address, sizeof(struct acpi_table_rsdp)); 630 if (!rsdp) { 631 return_ACPI_STATUS(AE_NO_MEMORY); 632 } 633 634 acpi_tb_print_table_header(rsdp_address, 635 ACPI_CAST_PTR(struct acpi_table_header, 636 rsdp)); 637 638 /* Differentiate between RSDT and XSDT root tables */ 639 640 if (rsdp->revision > 1 && rsdp->xsdt_physical_address 641 && !acpi_rsdt_forced) { 642 /* 643 * Root table is an XSDT (64-bit physical addresses). We must use the 644 * XSDT if the revision is > 1 and the XSDT pointer is present, as per 645 * the ACPI specification. 646 */ 647 address = (acpi_physical_address) rsdp->xsdt_physical_address; 648 table_entry_size = sizeof(u64); 649 rsdt_address = (acpi_physical_address) 650 rsdp->rsdt_physical_address; 651 } else { 652 /* Root table is an RSDT (32-bit physical addresses) */ 653 654 address = (acpi_physical_address) rsdp->rsdt_physical_address; 655 table_entry_size = sizeof(u32); 656 } 657 658 /* 659 * It is not possible to map more than one entry in some environments, 660 * so unmap the RSDP here before mapping other tables 661 */ 662 acpi_os_unmap_memory(rsdp, sizeof(struct acpi_table_rsdp)); 663 664 if (table_entry_size == sizeof(u64)) { 665 if (acpi_tb_check_xsdt(address) == AE_NULL_ENTRY) { 666 /* XSDT has NULL entry, RSDT is used */ 667 address = rsdt_address; 668 table_entry_size = sizeof(u32); 669 ACPI_WARNING((AE_INFO, "BIOS XSDT has NULL entry, " 670 "using RSDT")); 671 } 672 } 673 /* Map the RSDT/XSDT table header to get the full table length */ 674 675 table = acpi_os_map_memory(address, sizeof(struct acpi_table_header)); 676 if (!table) { 677 return_ACPI_STATUS(AE_NO_MEMORY); 678 } 679 680 acpi_tb_print_table_header(address, table); 681 682 /* Get the length of the full table, verify length and map entire table */ 683 684 length = table->length; 685 acpi_os_unmap_memory(table, sizeof(struct acpi_table_header)); 686 687 if (length < sizeof(struct acpi_table_header)) { 688 ACPI_ERROR((AE_INFO, "Invalid length 0x%X in RSDT/XSDT", 689 length)); 690 return_ACPI_STATUS(AE_INVALID_TABLE_LENGTH); 691 } 692 693 table = acpi_os_map_memory(address, length); 694 if (!table) { 695 return_ACPI_STATUS(AE_NO_MEMORY); 696 } 697 698 /* Validate the root table checksum */ 699 700 status = acpi_tb_verify_checksum(table, length); 701 if (ACPI_FAILURE(status)) { 702 acpi_os_unmap_memory(table, length); 703 return_ACPI_STATUS(status); 704 } 705 706 /* Calculate the number of tables described in the root table */ 707 708 table_count = (u32)((table->length - sizeof(struct acpi_table_header)) / 709 table_entry_size); 710 /* 711 * First two entries in the table array are reserved for the DSDT 712 * and FACS, which are not actually present in the RSDT/XSDT - they 713 * come from the FADT 714 */ 715 table_entry = 716 ACPI_CAST_PTR(u8, table) + sizeof(struct acpi_table_header); 717 acpi_gbl_root_table_list.current_table_count = 2; 718 719 /* 720 * Initialize the root table array from the RSDT/XSDT 721 */ 722 for (i = 0; i < table_count; i++) { 723 if (acpi_gbl_root_table_list.current_table_count >= 724 acpi_gbl_root_table_list.max_table_count) { 725 726 /* There is no more room in the root table array, attempt resize */ 727 728 status = acpi_tb_resize_root_table_list(); 729 if (ACPI_FAILURE(status)) { 730 ACPI_WARNING((AE_INFO, 731 "Truncating %u table entries!", 732 (unsigned) (table_count - 733 (acpi_gbl_root_table_list. 734 current_table_count - 735 2)))); 736 break; 737 } 738 } 739 740 /* Get the table physical address (32-bit for RSDT, 64-bit for XSDT) */ 741 742 acpi_gbl_root_table_list.tables[acpi_gbl_root_table_list. 743 current_table_count].address = 744 acpi_tb_get_root_table_entry(table_entry, table_entry_size); 745 746 table_entry += table_entry_size; 747 acpi_gbl_root_table_list.current_table_count++; 748 } 749 750 /* 751 * It is not possible to map more than one entry in some environments, 752 * so unmap the root table here before mapping other tables 753 */ 754 acpi_os_unmap_memory(table, length); 755 756 /* 757 * Complete the initialization of the root table array by examining 758 * the header of each table 759 */ 760 for (i = 2; i < acpi_gbl_root_table_list.current_table_count; i++) { 761 acpi_tb_install_table(acpi_gbl_root_table_list.tables[i]. 762 address, NULL, i); 763 764 /* Special case for FADT - get the DSDT and FACS */ 765 766 if (ACPI_COMPARE_NAME 767 (&acpi_gbl_root_table_list.tables[i].signature, 768 ACPI_SIG_FADT)) { 769 acpi_tb_parse_fadt(i); 770 } 771 } 772 773 return_ACPI_STATUS(AE_OK); 774 } 775