Linux 2.6.33-rc8
[linux-2.6/lguest.git] / drivers / acpi / acpica / tbutils.c
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1 /******************************************************************************
3 * Module Name: tbutils - table utilities
5 *****************************************************************************/
7 /*
8 * Copyright (C) 2000 - 2008, Intel Corp.
9 * All rights reserved.
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.
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.
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.
44 #include <acpi/acpi.h>
45 #include "accommon.h"
46 #include "actables.h"
48 #define _COMPONENT ACPI_TABLES
49 ACPI_MODULE_NAME("tbutils")
51 /* Local prototypes */
52 static void acpi_tb_fix_string(char *string, acpi_size length);
54 static void
55 acpi_tb_cleanup_table_header(struct acpi_table_header *out_header,
56 struct acpi_table_header *header);
58 static acpi_physical_address
59 acpi_tb_get_root_table_entry(u8 *table_entry, u32 table_entry_size);
61 /*******************************************************************************
63 * FUNCTION: acpi_tb_check_xsdt
65 * PARAMETERS: address - Pointer to the XSDT
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
73 * DESCRIPTION: validate XSDT
74 ******************************************************************************/
76 static acpi_status
77 acpi_tb_check_xsdt(acpi_physical_address address)
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;
86 table = acpi_os_map_memory(address, sizeof(struct acpi_table_header));
87 if (!table)
88 return AE_NO_MEMORY;
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;
95 table = acpi_os_map_memory(address, length);
96 if (!table)
97 return AE_NO_MEMORY;
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;
111 table_entry += sizeof(u64);
113 acpi_os_unmap_memory(table, length);
115 if (i < table_count)
116 return AE_NULL_ENTRY;
117 else
118 return AE_OK;
121 /*******************************************************************************
123 * FUNCTION: acpi_tb_initialize_facs
125 * PARAMETERS: None
127 * RETURN: Status
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
132 ******************************************************************************/
134 acpi_status acpi_tb_initialize_facs(void)
136 acpi_status status;
138 status = acpi_get_table_by_index(ACPI_TABLE_INDEX_FACS,
139 ACPI_CAST_INDIRECT_PTR(struct
140 acpi_table_header,
141 &acpi_gbl_FACS));
142 return status;
145 /*******************************************************************************
147 * FUNCTION: acpi_tb_tables_loaded
149 * PARAMETERS: None
151 * RETURN: TRUE if required ACPI tables are loaded
153 * DESCRIPTION: Determine if the minimum required ACPI tables are present
154 * (FADT, FACS, DSDT)
156 ******************************************************************************/
158 u8 acpi_tb_tables_loaded(void)
161 if (acpi_gbl_root_table_list.count >= 3) {
162 return (TRUE);
165 return (FALSE);
168 /*******************************************************************************
170 * FUNCTION: acpi_tb_fix_string
172 * PARAMETERS: String - String to be repaired
173 * Length - Maximum length
175 * RETURN: None
177 * DESCRIPTION: Replace every non-printable or non-ascii byte in the string
178 * with a question mark '?'.
180 ******************************************************************************/
182 static void acpi_tb_fix_string(char *string, acpi_size length)
185 while (length && *string) {
186 if (!ACPI_IS_PRINT(*string)) {
187 *string = '?';
189 string++;
190 length--;
194 /*******************************************************************************
196 * FUNCTION: acpi_tb_cleanup_table_header
198 * PARAMETERS: out_header - Where the cleaned header is returned
199 * Header - Input ACPI table header
201 * RETURN: Returns the cleaned header in out_header
203 * DESCRIPTION: Copy the table header and ensure that all "string" fields in
204 * the header consist of printable characters.
206 ******************************************************************************/
208 static void
209 acpi_tb_cleanup_table_header(struct acpi_table_header *out_header,
210 struct acpi_table_header *header)
213 ACPI_MEMCPY(out_header, header, sizeof(struct acpi_table_header));
215 acpi_tb_fix_string(out_header->signature, ACPI_NAME_SIZE);
216 acpi_tb_fix_string(out_header->oem_id, ACPI_OEM_ID_SIZE);
217 acpi_tb_fix_string(out_header->oem_table_id, ACPI_OEM_TABLE_ID_SIZE);
218 acpi_tb_fix_string(out_header->asl_compiler_id, ACPI_NAME_SIZE);
221 /*******************************************************************************
223 * FUNCTION: acpi_tb_print_table_header
225 * PARAMETERS: Address - Table physical address
226 * Header - Table header
228 * RETURN: None
230 * DESCRIPTION: Print an ACPI table header. Special cases for FACS and RSDP.
232 ******************************************************************************/
234 void
235 acpi_tb_print_table_header(acpi_physical_address address,
236 struct acpi_table_header *header)
238 struct acpi_table_header local_header;
241 * The reason that the Address is cast to a void pointer is so that we
242 * can use %p which will work properly on both 32-bit and 64-bit hosts.
244 if (ACPI_COMPARE_NAME(header->signature, ACPI_SIG_FACS)) {
246 /* FACS only has signature and length fields */
248 ACPI_INFO((AE_INFO, "%4.4s %p %05X",
249 header->signature, ACPI_CAST_PTR(void, address),
250 header->length));
251 } else if (ACPI_COMPARE_NAME(header->signature, ACPI_SIG_RSDP)) {
253 /* RSDP has no common fields */
255 ACPI_MEMCPY(local_header.oem_id,
256 ACPI_CAST_PTR(struct acpi_table_rsdp,
257 header)->oem_id, ACPI_OEM_ID_SIZE);
258 acpi_tb_fix_string(local_header.oem_id, ACPI_OEM_ID_SIZE);
260 ACPI_INFO((AE_INFO, "RSDP %p %05X (v%.2d %6.6s)",
261 ACPI_CAST_PTR (void, address),
262 (ACPI_CAST_PTR(struct acpi_table_rsdp, header)->
263 revision >
264 0) ? ACPI_CAST_PTR(struct acpi_table_rsdp,
265 header)->length : 20,
266 ACPI_CAST_PTR(struct acpi_table_rsdp,
267 header)->revision,
268 local_header.oem_id));
269 } else {
270 /* Standard ACPI table with full common header */
272 acpi_tb_cleanup_table_header(&local_header, header);
274 ACPI_INFO((AE_INFO,
275 "%4.4s %p %05X (v%.2d %6.6s %8.8s %08X %4.4s %08X)",
276 local_header.signature, ACPI_CAST_PTR(void, address),
277 local_header.length, local_header.revision,
278 local_header.oem_id, local_header.oem_table_id,
279 local_header.oem_revision,
280 local_header.asl_compiler_id,
281 local_header.asl_compiler_revision));
286 /*******************************************************************************
288 * FUNCTION: acpi_tb_validate_checksum
290 * PARAMETERS: Table - ACPI table to verify
291 * Length - Length of entire table
293 * RETURN: Status
295 * DESCRIPTION: Verifies that the table checksums to zero. Optionally returns
296 * exception on bad checksum.
298 ******************************************************************************/
300 acpi_status acpi_tb_verify_checksum(struct acpi_table_header *table, u32 length)
302 u8 checksum;
304 /* Compute the checksum on the table */
306 checksum = acpi_tb_checksum(ACPI_CAST_PTR(u8, table), length);
308 /* Checksum ok? (should be zero) */
310 if (checksum) {
311 ACPI_WARNING((AE_INFO,
312 "Incorrect checksum in table [%4.4s] - %2.2X, should be %2.2X",
313 table->signature, table->checksum,
314 (u8) (table->checksum - checksum)));
316 #if (ACPI_CHECKSUM_ABORT)
318 return (AE_BAD_CHECKSUM);
319 #endif
322 return (AE_OK);
325 /*******************************************************************************
327 * FUNCTION: acpi_tb_checksum
329 * PARAMETERS: Buffer - Pointer to memory region to be checked
330 * Length - Length of this memory region
332 * RETURN: Checksum (u8)
334 * DESCRIPTION: Calculates circular checksum of memory region.
336 ******************************************************************************/
338 u8 acpi_tb_checksum(u8 *buffer, u32 length)
340 u8 sum = 0;
341 u8 *end = buffer + length;
343 while (buffer < end) {
344 sum = (u8) (sum + *(buffer++));
347 return sum;
350 /*******************************************************************************
352 * FUNCTION: acpi_tb_install_table
354 * PARAMETERS: Address - Physical address of DSDT or FACS
355 * Signature - Table signature, NULL if no need to
356 * match
357 * table_index - Index into root table array
359 * RETURN: None
361 * DESCRIPTION: Install an ACPI table into the global data structure. The
362 * table override mechanism is implemented here to allow the host
363 * OS to replace any table before it is installed in the root
364 * table array.
366 ******************************************************************************/
368 void
369 acpi_tb_install_table(acpi_physical_address address,
370 char *signature, u32 table_index)
372 u8 flags;
373 acpi_status status;
374 struct acpi_table_header *table_to_install;
375 struct acpi_table_header *mapped_table;
376 struct acpi_table_header *override_table = NULL;
378 if (!address) {
379 ACPI_ERROR((AE_INFO,
380 "Null physical address for ACPI table [%s]",
381 signature));
382 return;
385 /* Map just the table header */
387 mapped_table =
388 acpi_os_map_memory(address, sizeof(struct acpi_table_header));
389 if (!mapped_table) {
390 return;
393 /* If a particular signature is expected (DSDT/FACS), it must match */
395 if (signature && !ACPI_COMPARE_NAME(mapped_table->signature, signature)) {
396 ACPI_ERROR((AE_INFO,
397 "Invalid signature 0x%X for ACPI table, expected [%s]",
398 *ACPI_CAST_PTR(u32, mapped_table->signature),
399 signature));
400 goto unmap_and_exit;
404 * ACPI Table Override:
406 * Before we install the table, let the host OS override it with a new
407 * one if desired. Any table within the RSDT/XSDT can be replaced,
408 * including the DSDT which is pointed to by the FADT.
410 status = acpi_os_table_override(mapped_table, &override_table);
411 if (ACPI_SUCCESS(status) && override_table) {
412 ACPI_INFO((AE_INFO,
413 "%4.4s @ 0x%p Table override, replaced with:",
414 mapped_table->signature, ACPI_CAST_PTR(void,
415 address)));
417 acpi_gbl_root_table_list.tables[table_index].pointer =
418 override_table;
419 address = ACPI_PTR_TO_PHYSADDR(override_table);
421 table_to_install = override_table;
422 flags = ACPI_TABLE_ORIGIN_OVERRIDE;
423 } else {
424 table_to_install = mapped_table;
425 flags = ACPI_TABLE_ORIGIN_MAPPED;
428 /* Initialize the table entry */
430 acpi_gbl_root_table_list.tables[table_index].address = address;
431 acpi_gbl_root_table_list.tables[table_index].length =
432 table_to_install->length;
433 acpi_gbl_root_table_list.tables[table_index].flags = flags;
435 ACPI_MOVE_32_TO_32(&
436 (acpi_gbl_root_table_list.tables[table_index].
437 signature), table_to_install->signature);
439 acpi_tb_print_table_header(address, table_to_install);
441 if (table_index == ACPI_TABLE_INDEX_DSDT) {
443 /* Global integer width is based upon revision of the DSDT */
445 acpi_ut_set_integer_width(table_to_install->revision);
448 unmap_and_exit:
449 acpi_os_unmap_memory(mapped_table, sizeof(struct acpi_table_header));
452 /*******************************************************************************
454 * FUNCTION: acpi_tb_get_root_table_entry
456 * PARAMETERS: table_entry - Pointer to the RSDT/XSDT table entry
457 * table_entry_size - sizeof 32 or 64 (RSDT or XSDT)
459 * RETURN: Physical address extracted from the root table
461 * DESCRIPTION: Get one root table entry. Handles 32-bit and 64-bit cases on
462 * both 32-bit and 64-bit platforms
464 * NOTE: acpi_physical_address is 32-bit on 32-bit platforms, 64-bit on
465 * 64-bit platforms.
467 ******************************************************************************/
469 static acpi_physical_address
470 acpi_tb_get_root_table_entry(u8 *table_entry, u32 table_entry_size)
472 u64 address64;
475 * Get the table physical address (32-bit for RSDT, 64-bit for XSDT):
476 * Note: Addresses are 32-bit aligned (not 64) in both RSDT and XSDT
478 if (table_entry_size == sizeof(u32)) {
480 * 32-bit platform, RSDT: Return 32-bit table entry
481 * 64-bit platform, RSDT: Expand 32-bit to 64-bit and return
483 return ((acpi_physical_address)
484 (*ACPI_CAST_PTR(u32, table_entry)));
485 } else {
487 * 32-bit platform, XSDT: Truncate 64-bit to 32-bit and return
488 * 64-bit platform, XSDT: Move (unaligned) 64-bit to local,
489 * return 64-bit
491 ACPI_MOVE_64_TO_64(&address64, table_entry);
493 #if ACPI_MACHINE_WIDTH == 32
494 if (address64 > ACPI_UINT32_MAX) {
496 /* Will truncate 64-bit address to 32 bits, issue warning */
498 ACPI_WARNING((AE_INFO,
499 "64-bit Physical Address in XSDT is too large (%8.8X%8.8X),"
500 " truncating",
501 ACPI_FORMAT_UINT64(address64)));
503 #endif
504 return ((acpi_physical_address) (address64));
508 /*******************************************************************************
510 * FUNCTION: acpi_tb_parse_root_table
512 * PARAMETERS: Rsdp - Pointer to the RSDP
514 * RETURN: Status
516 * DESCRIPTION: This function is called to parse the Root System Description
517 * Table (RSDT or XSDT)
519 * NOTE: Tables are mapped (not copied) for efficiency. The FACS must
520 * be mapped and cannot be copied because it contains the actual
521 * memory location of the ACPI Global Lock.
523 ******************************************************************************/
525 acpi_status __init
526 acpi_tb_parse_root_table(acpi_physical_address rsdp_address)
528 struct acpi_table_rsdp *rsdp;
529 u32 table_entry_size;
530 u32 i;
531 u32 table_count;
532 struct acpi_table_header *table;
533 acpi_physical_address address;
534 acpi_physical_address uninitialized_var(rsdt_address);
535 u32 length;
536 u8 *table_entry;
537 acpi_status status;
539 ACPI_FUNCTION_TRACE(tb_parse_root_table);
542 * Map the entire RSDP and extract the address of the RSDT or XSDT
544 rsdp = acpi_os_map_memory(rsdp_address, sizeof(struct acpi_table_rsdp));
545 if (!rsdp) {
546 return_ACPI_STATUS(AE_NO_MEMORY);
549 acpi_tb_print_table_header(rsdp_address,
550 ACPI_CAST_PTR(struct acpi_table_header,
551 rsdp));
553 /* Differentiate between RSDT and XSDT root tables */
555 if (rsdp->revision > 1 && rsdp->xsdt_physical_address
556 && !acpi_rsdt_forced) {
558 * Root table is an XSDT (64-bit physical addresses). We must use the
559 * XSDT if the revision is > 1 and the XSDT pointer is present, as per
560 * the ACPI specification.
562 address = (acpi_physical_address) rsdp->xsdt_physical_address;
563 table_entry_size = sizeof(u64);
564 rsdt_address = (acpi_physical_address)
565 rsdp->rsdt_physical_address;
566 } else {
567 /* Root table is an RSDT (32-bit physical addresses) */
569 address = (acpi_physical_address) rsdp->rsdt_physical_address;
570 table_entry_size = sizeof(u32);
574 * It is not possible to map more than one entry in some environments,
575 * so unmap the RSDP here before mapping other tables
577 acpi_os_unmap_memory(rsdp, sizeof(struct acpi_table_rsdp));
579 if (table_entry_size == sizeof(u64)) {
580 if (acpi_tb_check_xsdt(address) == AE_NULL_ENTRY) {
581 /* XSDT has NULL entry, RSDT is used */
582 address = rsdt_address;
583 table_entry_size = sizeof(u32);
584 ACPI_WARNING((AE_INFO, "BIOS XSDT has NULL entry, "
585 "using RSDT"));
588 /* Map the RSDT/XSDT table header to get the full table length */
590 table = acpi_os_map_memory(address, sizeof(struct acpi_table_header));
591 if (!table) {
592 return_ACPI_STATUS(AE_NO_MEMORY);
595 acpi_tb_print_table_header(address, table);
597 /* Get the length of the full table, verify length and map entire table */
599 length = table->length;
600 acpi_os_unmap_memory(table, sizeof(struct acpi_table_header));
602 if (length < sizeof(struct acpi_table_header)) {
603 ACPI_ERROR((AE_INFO, "Invalid length 0x%X in RSDT/XSDT",
604 length));
605 return_ACPI_STATUS(AE_INVALID_TABLE_LENGTH);
608 table = acpi_os_map_memory(address, length);
609 if (!table) {
610 return_ACPI_STATUS(AE_NO_MEMORY);
613 /* Validate the root table checksum */
615 status = acpi_tb_verify_checksum(table, length);
616 if (ACPI_FAILURE(status)) {
617 acpi_os_unmap_memory(table, length);
618 return_ACPI_STATUS(status);
621 /* Calculate the number of tables described in the root table */
623 table_count = (u32)((table->length - sizeof(struct acpi_table_header)) /
624 table_entry_size);
626 * First two entries in the table array are reserved for the DSDT
627 * and FACS, which are not actually present in the RSDT/XSDT - they
628 * come from the FADT
630 table_entry =
631 ACPI_CAST_PTR(u8, table) + sizeof(struct acpi_table_header);
632 acpi_gbl_root_table_list.count = 2;
635 * Initialize the root table array from the RSDT/XSDT
637 for (i = 0; i < table_count; i++) {
638 if (acpi_gbl_root_table_list.count >=
639 acpi_gbl_root_table_list.size) {
641 /* There is no more room in the root table array, attempt resize */
643 status = acpi_tb_resize_root_table_list();
644 if (ACPI_FAILURE(status)) {
645 ACPI_WARNING((AE_INFO,
646 "Truncating %u table entries!",
647 (unsigned) (table_count -
648 (acpi_gbl_root_table_list.
649 count - 2))));
650 break;
654 /* Get the table physical address (32-bit for RSDT, 64-bit for XSDT) */
656 acpi_gbl_root_table_list.tables[acpi_gbl_root_table_list.count].
657 address =
658 acpi_tb_get_root_table_entry(table_entry, table_entry_size);
660 table_entry += table_entry_size;
661 acpi_gbl_root_table_list.count++;
665 * It is not possible to map more than one entry in some environments,
666 * so unmap the root table here before mapping other tables
668 acpi_os_unmap_memory(table, length);
671 * Complete the initialization of the root table array by examining
672 * the header of each table
674 for (i = 2; i < acpi_gbl_root_table_list.count; i++) {
675 acpi_tb_install_table(acpi_gbl_root_table_list.tables[i].
676 address, NULL, i);
678 /* Special case for FADT - get the DSDT and FACS */
680 if (ACPI_COMPARE_NAME
681 (&acpi_gbl_root_table_list.tables[i].signature,
682 ACPI_SIG_FADT)) {
683 acpi_tb_parse_fadt(i);
687 return_ACPI_STATUS(AE_OK);