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
acpi_tb_check_xsdt(acpi_physical_address address)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 #if (!ACPI_REDUCED_HARDWARE)
122 /*******************************************************************************
123 *
124 * FUNCTION: acpi_tb_initialize_facs
125 *
126 * PARAMETERS: None
127 *
128 * RETURN: Status
129 *
130 * DESCRIPTION: Create a permanent mapping for the FADT and save it in a global
131 * for accessing the Global Lock and Firmware Waking Vector
132 *
133 ******************************************************************************/
134
acpi_tb_initialize_facs(void)135 acpi_status acpi_tb_initialize_facs(void)
136 {
137 acpi_status status;
138
139 /* If Hardware Reduced flag is set, there is no FACS */
140
141 if (acpi_gbl_reduced_hardware) {
142 acpi_gbl_FACS = NULL;
143 return (AE_OK);
144 }
145
146 status = acpi_get_table_by_index(ACPI_TABLE_INDEX_FACS,
147 ACPI_CAST_INDIRECT_PTR(struct
148 acpi_table_header,
149 &acpi_gbl_FACS));
150 return status;
151 }
152 #endif /* !ACPI_REDUCED_HARDWARE */
153
154 /*******************************************************************************
155 *
156 * FUNCTION: acpi_tb_tables_loaded
157 *
158 * PARAMETERS: None
159 *
160 * RETURN: TRUE if required ACPI tables are loaded
161 *
162 * DESCRIPTION: Determine if the minimum required ACPI tables are present
163 * (FADT, FACS, DSDT)
164 *
165 ******************************************************************************/
166
acpi_tb_tables_loaded(void)167 u8 acpi_tb_tables_loaded(void)
168 {
169
170 if (acpi_gbl_root_table_list.current_table_count >= 3) {
171 return (TRUE);
172 }
173
174 return (FALSE);
175 }
176
177 /*******************************************************************************
178 *
179 * FUNCTION: acpi_tb_fix_string
180 *
181 * PARAMETERS: String - String to be repaired
182 * Length - Maximum length
183 *
184 * RETURN: None
185 *
186 * DESCRIPTION: Replace every non-printable or non-ascii byte in the string
187 * with a question mark '?'.
188 *
189 ******************************************************************************/
190
acpi_tb_fix_string(char * string,acpi_size length)191 static void acpi_tb_fix_string(char *string, acpi_size length)
192 {
193
194 while (length && *string) {
195 if (!ACPI_IS_PRINT(*string)) {
196 *string = '?';
197 }
198 string++;
199 length--;
200 }
201 }
202
203 /*******************************************************************************
204 *
205 * FUNCTION: acpi_tb_cleanup_table_header
206 *
207 * PARAMETERS: out_header - Where the cleaned header is returned
208 * Header - Input ACPI table header
209 *
210 * RETURN: Returns the cleaned header in out_header
211 *
212 * DESCRIPTION: Copy the table header and ensure that all "string" fields in
213 * the header consist of printable characters.
214 *
215 ******************************************************************************/
216
217 static void
acpi_tb_cleanup_table_header(struct acpi_table_header * out_header,struct acpi_table_header * header)218 acpi_tb_cleanup_table_header(struct acpi_table_header *out_header,
219 struct acpi_table_header *header)
220 {
221
222 ACPI_MEMCPY(out_header, header, sizeof(struct acpi_table_header));
223
224 acpi_tb_fix_string(out_header->signature, ACPI_NAME_SIZE);
225 acpi_tb_fix_string(out_header->oem_id, ACPI_OEM_ID_SIZE);
226 acpi_tb_fix_string(out_header->oem_table_id, ACPI_OEM_TABLE_ID_SIZE);
227 acpi_tb_fix_string(out_header->asl_compiler_id, ACPI_NAME_SIZE);
228 }
229
230 /*******************************************************************************
231 *
232 * FUNCTION: acpi_tb_print_table_header
233 *
234 * PARAMETERS: Address - Table physical address
235 * Header - Table header
236 *
237 * RETURN: None
238 *
239 * DESCRIPTION: Print an ACPI table header. Special cases for FACS and RSDP.
240 *
241 ******************************************************************************/
242
243 void
acpi_tb_print_table_header(acpi_physical_address address,struct acpi_table_header * header)244 acpi_tb_print_table_header(acpi_physical_address address,
245 struct acpi_table_header *header)
246 {
247 struct acpi_table_header local_header;
248
249 /*
250 * The reason that the Address is cast to a void pointer is so that we
251 * can use %p which will work properly on both 32-bit and 64-bit hosts.
252 */
253 if (ACPI_COMPARE_NAME(header->signature, ACPI_SIG_FACS)) {
254
255 /* FACS only has signature and length fields */
256
257 ACPI_INFO((AE_INFO, "%4.4s %p %05X",
258 header->signature, ACPI_CAST_PTR(void, address),
259 header->length));
260 } else if (ACPI_COMPARE_NAME(header->signature, ACPI_SIG_RSDP)) {
261
262 /* RSDP has no common fields */
263
264 ACPI_MEMCPY(local_header.oem_id,
265 ACPI_CAST_PTR(struct acpi_table_rsdp,
266 header)->oem_id, ACPI_OEM_ID_SIZE);
267 acpi_tb_fix_string(local_header.oem_id, ACPI_OEM_ID_SIZE);
268
269 ACPI_INFO((AE_INFO, "RSDP %p %05X (v%.2d %6.6s)",
270 ACPI_CAST_PTR (void, address),
271 (ACPI_CAST_PTR(struct acpi_table_rsdp, header)->
272 revision >
273 0) ? ACPI_CAST_PTR(struct acpi_table_rsdp,
274 header)->length : 20,
275 ACPI_CAST_PTR(struct acpi_table_rsdp,
276 header)->revision,
277 local_header.oem_id));
278 } else {
279 /* Standard ACPI table with full common header */
280
281 acpi_tb_cleanup_table_header(&local_header, header);
282
283 ACPI_INFO((AE_INFO,
284 "%4.4s %p %05X (v%.2d %6.6s %8.8s %08X %4.4s %08X)",
285 local_header.signature, ACPI_CAST_PTR(void, address),
286 local_header.length, local_header.revision,
287 local_header.oem_id, local_header.oem_table_id,
288 local_header.oem_revision,
289 local_header.asl_compiler_id,
290 local_header.asl_compiler_revision));
291
292 }
293 }
294
295 /*******************************************************************************
296 *
297 * FUNCTION: acpi_tb_validate_checksum
298 *
299 * PARAMETERS: Table - ACPI table to verify
300 * Length - Length of entire table
301 *
302 * RETURN: Status
303 *
304 * DESCRIPTION: Verifies that the table checksums to zero. Optionally returns
305 * exception on bad checksum.
306 *
307 ******************************************************************************/
308
acpi_tb_verify_checksum(struct acpi_table_header * table,u32 length)309 acpi_status acpi_tb_verify_checksum(struct acpi_table_header *table, u32 length)
310 {
311 u8 checksum;
312
313 /* Compute the checksum on the table */
314
315 checksum = acpi_tb_checksum(ACPI_CAST_PTR(u8, table), length);
316
317 /* Checksum ok? (should be zero) */
318
319 if (checksum) {
320 ACPI_WARNING((AE_INFO,
321 "Incorrect checksum in table [%4.4s] - 0x%2.2X, should be 0x%2.2X",
322 table->signature, table->checksum,
323 (u8) (table->checksum - checksum)));
324
325 #if (ACPI_CHECKSUM_ABORT)
326
327 return (AE_BAD_CHECKSUM);
328 #endif
329 }
330
331 return (AE_OK);
332 }
333
334 /*******************************************************************************
335 *
336 * FUNCTION: acpi_tb_checksum
337 *
338 * PARAMETERS: Buffer - Pointer to memory region to be checked
339 * Length - Length of this memory region
340 *
341 * RETURN: Checksum (u8)
342 *
343 * DESCRIPTION: Calculates circular checksum of memory region.
344 *
345 ******************************************************************************/
346
acpi_tb_checksum(u8 * buffer,u32 length)347 u8 acpi_tb_checksum(u8 *buffer, u32 length)
348 {
349 u8 sum = 0;
350 u8 *end = buffer + length;
351
352 while (buffer < end) {
353 sum = (u8) (sum + *(buffer++));
354 }
355
356 return sum;
357 }
358
359 /*******************************************************************************
360 *
361 * FUNCTION: acpi_tb_check_dsdt_header
362 *
363 * PARAMETERS: None
364 *
365 * RETURN: None
366 *
367 * DESCRIPTION: Quick compare to check validity of the DSDT. This will detect
368 * if the DSDT has been replaced from outside the OS and/or if
369 * the DSDT header has been corrupted.
370 *
371 ******************************************************************************/
372
acpi_tb_check_dsdt_header(void)373 void acpi_tb_check_dsdt_header(void)
374 {
375
376 /* Compare original length and checksum to current values */
377
378 if (acpi_gbl_original_dsdt_header.length != acpi_gbl_DSDT->length ||
379 acpi_gbl_original_dsdt_header.checksum != acpi_gbl_DSDT->checksum) {
380 ACPI_ERROR((AE_INFO,
381 "The DSDT has been corrupted or replaced - old, new headers below"));
382 acpi_tb_print_table_header(0, &acpi_gbl_original_dsdt_header);
383 acpi_tb_print_table_header(0, acpi_gbl_DSDT);
384
385 ACPI_ERROR((AE_INFO,
386 "Please send DMI info to linux-acpi@vger.kernel.org\n"
387 "If system does not work as expected, please boot with acpi=copy_dsdt"));
388
389 /* Disable further error messages */
390
391 acpi_gbl_original_dsdt_header.length = acpi_gbl_DSDT->length;
392 acpi_gbl_original_dsdt_header.checksum =
393 acpi_gbl_DSDT->checksum;
394 }
395 }
396
397 /*******************************************************************************
398 *
399 * FUNCTION: acpi_tb_copy_dsdt
400 *
401 * PARAMETERS: table_desc - Installed table to copy
402 *
403 * RETURN: None
404 *
405 * DESCRIPTION: Implements a subsystem option to copy the DSDT to local memory.
406 * Some very bad BIOSs are known to either corrupt the DSDT or
407 * install a new, bad DSDT. This copy works around the problem.
408 *
409 ******************************************************************************/
410
acpi_tb_copy_dsdt(u32 table_index)411 struct acpi_table_header *acpi_tb_copy_dsdt(u32 table_index)
412 {
413 struct acpi_table_header *new_table;
414 struct acpi_table_desc *table_desc;
415
416 table_desc = &acpi_gbl_root_table_list.tables[table_index];
417
418 new_table = ACPI_ALLOCATE(table_desc->length);
419 if (!new_table) {
420 ACPI_ERROR((AE_INFO, "Could not copy DSDT of length 0x%X",
421 table_desc->length));
422 return (NULL);
423 }
424
425 ACPI_MEMCPY(new_table, table_desc->pointer, table_desc->length);
426 acpi_tb_delete_table(table_desc);
427 table_desc->pointer = new_table;
428 table_desc->flags = ACPI_TABLE_ORIGIN_ALLOCATED;
429
430 ACPI_INFO((AE_INFO,
431 "Forced DSDT copy: length 0x%05X copied locally, original unmapped",
432 new_table->length));
433
434 return (new_table);
435 }
436
437 /*******************************************************************************
438 *
439 * FUNCTION: acpi_tb_install_table
440 *
441 * PARAMETERS: Address - Physical address of DSDT or FACS
442 * Signature - Table signature, NULL if no need to
443 * match
444 * table_index - Index into root table array
445 *
446 * RETURN: None
447 *
448 * DESCRIPTION: Install an ACPI table into the global data structure. The
449 * table override mechanism is called to allow the host
450 * OS to replace any table before it is installed in the root
451 * table array.
452 *
453 ******************************************************************************/
454
455 void
acpi_tb_install_table(acpi_physical_address address,char * signature,u32 table_index)456 acpi_tb_install_table(acpi_physical_address address,
457 char *signature, u32 table_index)
458 {
459 struct acpi_table_header *table;
460 struct acpi_table_header *final_table;
461 struct acpi_table_desc *table_desc;
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 table = acpi_os_map_memory(address, sizeof(struct acpi_table_header));
473 if (!table) {
474 ACPI_ERROR((AE_INFO,
475 "Could not map memory for table [%s] at %p",
476 signature, ACPI_CAST_PTR(void, address)));
477 return;
478 }
479
480 /* If a particular signature is expected (DSDT/FACS), it must match */
481
482 if (signature && !ACPI_COMPARE_NAME(table->signature, signature)) {
483 ACPI_ERROR((AE_INFO,
484 "Invalid signature 0x%X for ACPI table, expected [%s]",
485 *ACPI_CAST_PTR(u32, table->signature), signature));
486 goto unmap_and_exit;
487 }
488
489 /*
490 * Initialize the table entry. Set the pointer to NULL, since the
491 * table is not fully mapped at this time.
492 */
493 table_desc = &acpi_gbl_root_table_list.tables[table_index];
494
495 table_desc->address = address;
496 table_desc->pointer = NULL;
497 table_desc->length = table->length;
498 table_desc->flags = ACPI_TABLE_ORIGIN_MAPPED;
499 ACPI_MOVE_32_TO_32(table_desc->signature.ascii, table->signature);
500
501 /*
502 * ACPI Table Override:
503 *
504 * Before we install the table, let the host OS override it with a new
505 * one if desired. Any table within the RSDT/XSDT can be replaced,
506 * including the DSDT which is pointed to by the FADT.
507 *
508 * NOTE: If the table is overridden, then final_table will contain a
509 * mapped pointer to the full new table. If the table is not overridden,
510 * or if there has been a physical override, then the table will be
511 * fully mapped later (in verify table). In any case, we must
512 * unmap the header that was mapped above.
513 */
514 final_table = acpi_tb_table_override(table, table_desc);
515 if (!final_table) {
516 final_table = table; /* There was no override */
517 }
518
519 acpi_tb_print_table_header(table_desc->address, final_table);
520
521 /* Set the global integer width (based upon revision of the DSDT) */
522
523 if (table_index == ACPI_TABLE_INDEX_DSDT) {
524 acpi_ut_set_integer_width(final_table->revision);
525 }
526
527 /*
528 * If we have a physical override during this early loading of the ACPI
529 * tables, unmap the table for now. It will be mapped again later when
530 * it is actually used. This supports very early loading of ACPI tables,
531 * before virtual memory is fully initialized and running within the
532 * host OS. Note: A logical override has the ACPI_TABLE_ORIGIN_OVERRIDE
533 * flag set and will not be deleted below.
534 */
535 if (final_table != table) {
536 acpi_tb_delete_table(table_desc);
537 }
538
539 unmap_and_exit:
540
541 /* Always unmap the table header that we mapped above */
542
543 acpi_os_unmap_memory(table, sizeof(struct acpi_table_header));
544 }
545
546 /*******************************************************************************
547 *
548 * FUNCTION: acpi_tb_get_root_table_entry
549 *
550 * PARAMETERS: table_entry - Pointer to the RSDT/XSDT table entry
551 * table_entry_size - sizeof 32 or 64 (RSDT or XSDT)
552 *
553 * RETURN: Physical address extracted from the root table
554 *
555 * DESCRIPTION: Get one root table entry. Handles 32-bit and 64-bit cases on
556 * both 32-bit and 64-bit platforms
557 *
558 * NOTE: acpi_physical_address is 32-bit on 32-bit platforms, 64-bit on
559 * 64-bit platforms.
560 *
561 ******************************************************************************/
562
563 static acpi_physical_address
acpi_tb_get_root_table_entry(u8 * table_entry,u32 table_entry_size)564 acpi_tb_get_root_table_entry(u8 *table_entry, u32 table_entry_size)
565 {
566 u64 address64;
567
568 /*
569 * Get the table physical address (32-bit for RSDT, 64-bit for XSDT):
570 * Note: Addresses are 32-bit aligned (not 64) in both RSDT and XSDT
571 */
572 if (table_entry_size == sizeof(u32)) {
573 /*
574 * 32-bit platform, RSDT: Return 32-bit table entry
575 * 64-bit platform, RSDT: Expand 32-bit to 64-bit and return
576 */
577 return ((acpi_physical_address)
578 (*ACPI_CAST_PTR(u32, table_entry)));
579 } else {
580 /*
581 * 32-bit platform, XSDT: Truncate 64-bit to 32-bit and return
582 * 64-bit platform, XSDT: Move (unaligned) 64-bit to local,
583 * return 64-bit
584 */
585 ACPI_MOVE_64_TO_64(&address64, table_entry);
586
587 #if ACPI_MACHINE_WIDTH == 32
588 if (address64 > ACPI_UINT32_MAX) {
589
590 /* Will truncate 64-bit address to 32 bits, issue warning */
591
592 ACPI_WARNING((AE_INFO,
593 "64-bit Physical Address in XSDT is too large (0x%8.8X%8.8X),"
594 " truncating",
595 ACPI_FORMAT_UINT64(address64)));
596 }
597 #endif
598 return ((acpi_physical_address) (address64));
599 }
600 }
601
602 /*******************************************************************************
603 *
604 * FUNCTION: acpi_tb_parse_root_table
605 *
606 * PARAMETERS: Rsdp - Pointer to the RSDP
607 *
608 * RETURN: Status
609 *
610 * DESCRIPTION: This function is called to parse the Root System Description
611 * Table (RSDT or XSDT)
612 *
613 * NOTE: Tables are mapped (not copied) for efficiency. The FACS must
614 * be mapped and cannot be copied because it contains the actual
615 * memory location of the ACPI Global Lock.
616 *
617 ******************************************************************************/
618
619 acpi_status __init
acpi_tb_parse_root_table(acpi_physical_address rsdp_address)620 acpi_tb_parse_root_table(acpi_physical_address rsdp_address)
621 {
622 struct acpi_table_rsdp *rsdp;
623 u32 table_entry_size;
624 u32 i;
625 u32 table_count;
626 struct acpi_table_header *table;
627 acpi_physical_address address;
628 acpi_physical_address uninitialized_var(rsdt_address);
629 u32 length;
630 u8 *table_entry;
631 acpi_status status;
632
633 ACPI_FUNCTION_TRACE(tb_parse_root_table);
634
635 /*
636 * Map the entire RSDP and extract the address of the RSDT or XSDT
637 */
638 rsdp = acpi_os_map_memory(rsdp_address, sizeof(struct acpi_table_rsdp));
639 if (!rsdp) {
640 return_ACPI_STATUS(AE_NO_MEMORY);
641 }
642
643 acpi_tb_print_table_header(rsdp_address,
644 ACPI_CAST_PTR(struct acpi_table_header,
645 rsdp));
646
647 /* Differentiate between RSDT and XSDT root tables */
648
649 if (rsdp->revision > 1 && rsdp->xsdt_physical_address
650 && !acpi_rsdt_forced) {
651 /*
652 * Root table is an XSDT (64-bit physical addresses). We must use the
653 * XSDT if the revision is > 1 and the XSDT pointer is present, as per
654 * the ACPI specification.
655 */
656 address = (acpi_physical_address) rsdp->xsdt_physical_address;
657 table_entry_size = sizeof(u64);
658 rsdt_address = (acpi_physical_address)
659 rsdp->rsdt_physical_address;
660 } else {
661 /* Root table is an RSDT (32-bit physical addresses) */
662
663 address = (acpi_physical_address) rsdp->rsdt_physical_address;
664 table_entry_size = sizeof(u32);
665 }
666
667 /*
668 * It is not possible to map more than one entry in some environments,
669 * so unmap the RSDP here before mapping other tables
670 */
671 acpi_os_unmap_memory(rsdp, sizeof(struct acpi_table_rsdp));
672
673 if (table_entry_size == sizeof(u64)) {
674 if (acpi_tb_check_xsdt(address) == AE_NULL_ENTRY) {
675 /* XSDT has NULL entry, RSDT is used */
676 address = rsdt_address;
677 table_entry_size = sizeof(u32);
678 ACPI_WARNING((AE_INFO, "BIOS XSDT has NULL entry, "
679 "using RSDT"));
680 }
681 }
682 /* Map the RSDT/XSDT table header to get the full table length */
683
684 table = acpi_os_map_memory(address, sizeof(struct acpi_table_header));
685 if (!table) {
686 return_ACPI_STATUS(AE_NO_MEMORY);
687 }
688
689 acpi_tb_print_table_header(address, table);
690
691 /* Get the length of the full table, verify length and map entire table */
692
693 length = table->length;
694 acpi_os_unmap_memory(table, sizeof(struct acpi_table_header));
695
696 if (length < sizeof(struct acpi_table_header)) {
697 ACPI_ERROR((AE_INFO, "Invalid length 0x%X in RSDT/XSDT",
698 length));
699 return_ACPI_STATUS(AE_INVALID_TABLE_LENGTH);
700 }
701
702 table = acpi_os_map_memory(address, length);
703 if (!table) {
704 return_ACPI_STATUS(AE_NO_MEMORY);
705 }
706
707 /* Validate the root table checksum */
708
709 status = acpi_tb_verify_checksum(table, length);
710 if (ACPI_FAILURE(status)) {
711 acpi_os_unmap_memory(table, length);
712 return_ACPI_STATUS(status);
713 }
714
715 /* Calculate the number of tables described in the root table */
716
717 table_count = (u32)((table->length - sizeof(struct acpi_table_header)) /
718 table_entry_size);
719 /*
720 * First two entries in the table array are reserved for the DSDT
721 * and FACS, which are not actually present in the RSDT/XSDT - they
722 * come from the FADT
723 */
724 table_entry =
725 ACPI_CAST_PTR(u8, table) + sizeof(struct acpi_table_header);
726 acpi_gbl_root_table_list.current_table_count = 2;
727
728 /*
729 * Initialize the root table array from the RSDT/XSDT
730 */
731 for (i = 0; i < table_count; i++) {
732 if (acpi_gbl_root_table_list.current_table_count >=
733 acpi_gbl_root_table_list.max_table_count) {
734
735 /* There is no more room in the root table array, attempt resize */
736
737 status = acpi_tb_resize_root_table_list();
738 if (ACPI_FAILURE(status)) {
739 ACPI_WARNING((AE_INFO,
740 "Truncating %u table entries!",
741 (unsigned) (table_count -
742 (acpi_gbl_root_table_list.
743 current_table_count -
744 2))));
745 break;
746 }
747 }
748
749 /* Get the table physical address (32-bit for RSDT, 64-bit for XSDT) */
750
751 acpi_gbl_root_table_list.tables[acpi_gbl_root_table_list.
752 current_table_count].address =
753 acpi_tb_get_root_table_entry(table_entry, table_entry_size);
754
755 table_entry += table_entry_size;
756 acpi_gbl_root_table_list.current_table_count++;
757 }
758
759 /*
760 * It is not possible to map more than one entry in some environments,
761 * so unmap the root table here before mapping other tables
762 */
763 acpi_os_unmap_memory(table, length);
764
765 /*
766 * Complete the initialization of the root table array by examining
767 * the header of each table
768 */
769 for (i = 2; i < acpi_gbl_root_table_list.current_table_count; i++) {
770 acpi_tb_install_table(acpi_gbl_root_table_list.tables[i].
771 address, NULL, i);
772
773 /* Special case for FADT - get the DSDT and FACS */
774
775 if (ACPI_COMPARE_NAME
776 (&acpi_gbl_root_table_list.tables[i].signature,
777 ACPI_SIG_FADT)) {
778 acpi_tb_parse_fadt(i);
779 }
780 }
781
782 return_ACPI_STATUS(AE_OK);
783 }
784