xref: /linux/tools/power/acpi/os_specific/service_layers/oslinuxtbl.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 /******************************************************************************
2  *
3  * Module Name: oslinuxtbl - Linux OSL for obtaining ACPI tables
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2015, 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 "acpidump.h"
45 
46 #define _COMPONENT          ACPI_OS_SERVICES
47 ACPI_MODULE_NAME("oslinuxtbl")
48 
49 #ifndef PATH_MAX
50 #define PATH_MAX 256
51 #endif
52 /* List of information about obtained ACPI tables */
53 typedef struct osl_table_info {
54 	struct osl_table_info *next;
55 	u32 instance;
56 	char signature[ACPI_NAME_SIZE];
57 
58 } osl_table_info;
59 
60 /* Local prototypes */
61 
62 static acpi_status osl_table_initialize(void);
63 
64 static acpi_status
65 osl_table_name_from_file(char *filename, char *signature, u32 *instance);
66 
67 static acpi_status osl_add_table_to_list(char *signature, u32 instance);
68 
69 static acpi_status
70 osl_read_table_from_file(char *filename,
71 			 acpi_size file_offset,
72 			 char *signature, struct acpi_table_header **table);
73 
74 static acpi_status
75 osl_map_table(acpi_size address,
76 	      char *signature, struct acpi_table_header **table);
77 
78 static void osl_unmap_table(struct acpi_table_header *table);
79 
80 static acpi_physical_address
81 osl_find_rsdp_via_efi_by_keyword(FILE * file, const char *keyword);
82 
83 static acpi_physical_address osl_find_rsdp_via_efi(void);
84 
85 static acpi_status osl_load_rsdp(void);
86 
87 static acpi_status osl_list_customized_tables(char *directory);
88 
89 static acpi_status
90 osl_get_customized_table(char *pathname,
91 			 char *signature,
92 			 u32 instance,
93 			 struct acpi_table_header **table,
94 			 acpi_physical_address * address);
95 
96 static acpi_status osl_list_bios_tables(void);
97 
98 static acpi_status
99 osl_get_bios_table(char *signature,
100 		   u32 instance,
101 		   struct acpi_table_header **table,
102 		   acpi_physical_address * address);
103 
104 static acpi_status osl_get_last_status(acpi_status default_status);
105 
106 /* File locations */
107 
108 #define DYNAMIC_TABLE_DIR   "/sys/firmware/acpi/tables/dynamic"
109 #define STATIC_TABLE_DIR    "/sys/firmware/acpi/tables"
110 #define EFI_SYSTAB          "/sys/firmware/efi/systab"
111 
112 /* Should we get dynamically loaded SSDTs from DYNAMIC_TABLE_DIR? */
113 
114 u8 gbl_dump_dynamic_tables = TRUE;
115 
116 /* Initialization flags */
117 
118 u8 gbl_table_list_initialized = FALSE;
119 
120 /* Local copies of main ACPI tables */
121 
122 struct acpi_table_rsdp gbl_rsdp;
123 struct acpi_table_fadt *gbl_fadt = NULL;
124 struct acpi_table_rsdt *gbl_rsdt = NULL;
125 struct acpi_table_xsdt *gbl_xsdt = NULL;
126 
127 /* Table addresses */
128 
129 acpi_physical_address gbl_fadt_address = 0;
130 acpi_physical_address gbl_rsdp_address = 0;
131 
132 /* Revision of RSD PTR */
133 
134 u8 gbl_revision = 0;
135 
136 struct osl_table_info *gbl_table_list_head = NULL;
137 u32 gbl_table_count = 0;
138 
139 /******************************************************************************
140  *
141  * FUNCTION:    osl_get_last_status
142  *
143  * PARAMETERS:  default_status  - Default error status to return
144  *
145  * RETURN:      Status; Converted from errno.
146  *
147  * DESCRIPTION: Get last errno and conver it to acpi_status.
148  *
149  *****************************************************************************/
150 
151 static acpi_status osl_get_last_status(acpi_status default_status)
152 {
153 
154 	switch (errno) {
155 	case EACCES:
156 	case EPERM:
157 
158 		return (AE_ACCESS);
159 
160 	case ENOENT:
161 
162 		return (AE_NOT_FOUND);
163 
164 	case ENOMEM:
165 
166 		return (AE_NO_MEMORY);
167 
168 	default:
169 
170 		return (default_status);
171 	}
172 }
173 
174 /******************************************************************************
175  *
176  * FUNCTION:    acpi_os_get_table_by_address
177  *
178  * PARAMETERS:  address         - Physical address of the ACPI table
179  *              table           - Where a pointer to the table is returned
180  *
181  * RETURN:      Status; Table buffer is returned if AE_OK.
182  *              AE_NOT_FOUND: A valid table was not found at the address
183  *
184  * DESCRIPTION: Get an ACPI table via a physical memory address.
185  *
186  *****************************************************************************/
187 
188 acpi_status
189 acpi_os_get_table_by_address(acpi_physical_address address,
190 			     struct acpi_table_header ** table)
191 {
192 	u32 table_length;
193 	struct acpi_table_header *mapped_table;
194 	struct acpi_table_header *local_table = NULL;
195 	acpi_status status = AE_OK;
196 
197 	/* Get main ACPI tables from memory on first invocation of this function */
198 
199 	status = osl_table_initialize();
200 	if (ACPI_FAILURE(status)) {
201 		return (status);
202 	}
203 
204 	/* Map the table and validate it */
205 
206 	status = osl_map_table(address, NULL, &mapped_table);
207 	if (ACPI_FAILURE(status)) {
208 		return (status);
209 	}
210 
211 	/* Copy table to local buffer and return it */
212 
213 	table_length = ap_get_table_length(mapped_table);
214 	if (table_length == 0) {
215 		status = AE_BAD_HEADER;
216 		goto exit;
217 	}
218 
219 	local_table = calloc(1, table_length);
220 	if (!local_table) {
221 		status = AE_NO_MEMORY;
222 		goto exit;
223 	}
224 
225 	memcpy(local_table, mapped_table, table_length);
226 
227 exit:
228 	osl_unmap_table(mapped_table);
229 	*table = local_table;
230 	return (status);
231 }
232 
233 /******************************************************************************
234  *
235  * FUNCTION:    acpi_os_get_table_by_name
236  *
237  * PARAMETERS:  signature       - ACPI Signature for desired table. Must be
238  *                                a null terminated 4-character string.
239  *              instance        - Multiple table support for SSDT/UEFI (0...n)
240  *                                Must be 0 for other tables.
241  *              table           - Where a pointer to the table is returned
242  *              address         - Where the table physical address is returned
243  *
244  * RETURN:      Status; Table buffer and physical address returned if AE_OK.
245  *              AE_LIMIT: Instance is beyond valid limit
246  *              AE_NOT_FOUND: A table with the signature was not found
247  *
248  * NOTE:        Assumes the input signature is uppercase.
249  *
250  *****************************************************************************/
251 
252 acpi_status
253 acpi_os_get_table_by_name(char *signature,
254 			  u32 instance,
255 			  struct acpi_table_header ** table,
256 			  acpi_physical_address * address)
257 {
258 	acpi_status status;
259 
260 	/* Get main ACPI tables from memory on first invocation of this function */
261 
262 	status = osl_table_initialize();
263 	if (ACPI_FAILURE(status)) {
264 		return (status);
265 	}
266 
267 	/* Not a main ACPI table, attempt to extract it from the RSDT/XSDT */
268 
269 	if (!gbl_dump_customized_tables) {
270 
271 		/* Attempt to get the table from the memory */
272 
273 		status =
274 		    osl_get_bios_table(signature, instance, table, address);
275 	} else {
276 		/* Attempt to get the table from the static directory */
277 
278 		status = osl_get_customized_table(STATIC_TABLE_DIR, signature,
279 						  instance, table, address);
280 	}
281 
282 	if (ACPI_FAILURE(status) && status == AE_LIMIT) {
283 		if (gbl_dump_dynamic_tables) {
284 
285 			/* Attempt to get a dynamic table */
286 
287 			status =
288 			    osl_get_customized_table(DYNAMIC_TABLE_DIR,
289 						     signature, instance, table,
290 						     address);
291 		}
292 	}
293 
294 	return (status);
295 }
296 
297 /******************************************************************************
298  *
299  * FUNCTION:    osl_add_table_to_list
300  *
301  * PARAMETERS:  signature       - Table signature
302  *              instance        - Table instance
303  *
304  * RETURN:      Status; Successfully added if AE_OK.
305  *              AE_NO_MEMORY: Memory allocation error
306  *
307  * DESCRIPTION: Insert a table structure into OSL table list.
308  *
309  *****************************************************************************/
310 
311 static acpi_status osl_add_table_to_list(char *signature, u32 instance)
312 {
313 	struct osl_table_info *new_info;
314 	struct osl_table_info *next;
315 	u32 next_instance = 0;
316 	u8 found = FALSE;
317 
318 	new_info = calloc(1, sizeof(struct osl_table_info));
319 	if (!new_info) {
320 		return (AE_NO_MEMORY);
321 	}
322 
323 	ACPI_MOVE_NAME(new_info->signature, signature);
324 
325 	if (!gbl_table_list_head) {
326 		gbl_table_list_head = new_info;
327 	} else {
328 		next = gbl_table_list_head;
329 		while (1) {
330 			if (ACPI_COMPARE_NAME(next->signature, signature)) {
331 				if (next->instance == instance) {
332 					found = TRUE;
333 				}
334 				if (next->instance >= next_instance) {
335 					next_instance = next->instance + 1;
336 				}
337 			}
338 
339 			if (!next->next) {
340 				break;
341 			}
342 			next = next->next;
343 		}
344 		next->next = new_info;
345 	}
346 
347 	if (found) {
348 		if (instance) {
349 			fprintf(stderr,
350 				"%4.4s: Warning unmatched table instance %d, expected %d\n",
351 				signature, instance, next_instance);
352 		}
353 		instance = next_instance;
354 	}
355 
356 	new_info->instance = instance;
357 	gbl_table_count++;
358 
359 	return (AE_OK);
360 }
361 
362 /******************************************************************************
363  *
364  * FUNCTION:    acpi_os_get_table_by_index
365  *
366  * PARAMETERS:  index           - Which table to get
367  *              table           - Where a pointer to the table is returned
368  *              instance        - Where a pointer to the table instance no. is
369  *                                returned
370  *              address         - Where the table physical address is returned
371  *
372  * RETURN:      Status; Table buffer and physical address returned if AE_OK.
373  *              AE_LIMIT: Index is beyond valid limit
374  *
375  * DESCRIPTION: Get an ACPI table via an index value (0 through n). Returns
376  *              AE_LIMIT when an invalid index is reached. Index is not
377  *              necessarily an index into the RSDT/XSDT.
378  *
379  *****************************************************************************/
380 
381 acpi_status
382 acpi_os_get_table_by_index(u32 index,
383 			   struct acpi_table_header ** table,
384 			   u32 *instance, acpi_physical_address * address)
385 {
386 	struct osl_table_info *info;
387 	acpi_status status;
388 	u32 i;
389 
390 	/* Get main ACPI tables from memory on first invocation of this function */
391 
392 	status = osl_table_initialize();
393 	if (ACPI_FAILURE(status)) {
394 		return (status);
395 	}
396 
397 	/* Validate Index */
398 
399 	if (index >= gbl_table_count) {
400 		return (AE_LIMIT);
401 	}
402 
403 	/* Point to the table list entry specified by the Index argument */
404 
405 	info = gbl_table_list_head;
406 	for (i = 0; i < index; i++) {
407 		info = info->next;
408 	}
409 
410 	/* Now we can just get the table via the signature */
411 
412 	status = acpi_os_get_table_by_name(info->signature, info->instance,
413 					   table, address);
414 
415 	if (ACPI_SUCCESS(status)) {
416 		*instance = info->instance;
417 	}
418 	return (status);
419 }
420 
421 /******************************************************************************
422  *
423  * FUNCTION:    osl_find_rsdp_via_efi_by_keyword
424  *
425  * PARAMETERS:  keyword         - Character string indicating ACPI GUID version
426  *                                in the EFI table
427  *
428  * RETURN:      RSDP address if found
429  *
430  * DESCRIPTION: Find RSDP address via EFI using keyword indicating the ACPI
431  *              GUID version.
432  *
433  *****************************************************************************/
434 
435 static acpi_physical_address
436 osl_find_rsdp_via_efi_by_keyword(FILE * file, const char *keyword)
437 {
438 	char buffer[80];
439 	unsigned long long address = 0;
440 	char format[32];
441 
442 	snprintf(format, 32, "%s=%s", keyword, "%llx");
443 	fseek(file, 0, SEEK_SET);
444 	while (fgets(buffer, 80, file)) {
445 		if (sscanf(buffer, format, &address) == 1) {
446 			break;
447 		}
448 	}
449 
450 	return ((acpi_physical_address) (address));
451 }
452 
453 /******************************************************************************
454  *
455  * FUNCTION:    osl_find_rsdp_via_efi
456  *
457  * PARAMETERS:  None
458  *
459  * RETURN:      RSDP address if found
460  *
461  * DESCRIPTION: Find RSDP address via EFI.
462  *
463  *****************************************************************************/
464 
465 static acpi_physical_address osl_find_rsdp_via_efi(void)
466 {
467 	FILE *file;
468 	acpi_physical_address address = 0;
469 
470 	file = fopen(EFI_SYSTAB, "r");
471 	if (file) {
472 		address = osl_find_rsdp_via_efi_by_keyword(file, "ACPI20");
473 		if (!address) {
474 			address =
475 			    osl_find_rsdp_via_efi_by_keyword(file, "ACPI");
476 		}
477 		fclose(file);
478 	}
479 
480 	return (address);
481 }
482 
483 /******************************************************************************
484  *
485  * FUNCTION:    osl_load_rsdp
486  *
487  * PARAMETERS:  None
488  *
489  * RETURN:      Status
490  *
491  * DESCRIPTION: Scan and load RSDP.
492  *
493  *****************************************************************************/
494 
495 static acpi_status osl_load_rsdp(void)
496 {
497 	struct acpi_table_header *mapped_table;
498 	u8 *rsdp_address;
499 	acpi_physical_address rsdp_base;
500 	acpi_size rsdp_size;
501 
502 	/* Get RSDP from memory */
503 
504 	rsdp_size = sizeof(struct acpi_table_rsdp);
505 	if (gbl_rsdp_base) {
506 		rsdp_base = gbl_rsdp_base;
507 	} else {
508 		rsdp_base = osl_find_rsdp_via_efi();
509 	}
510 
511 	if (!rsdp_base) {
512 		rsdp_base = ACPI_HI_RSDP_WINDOW_BASE;
513 		rsdp_size = ACPI_HI_RSDP_WINDOW_SIZE;
514 	}
515 
516 	rsdp_address = acpi_os_map_memory(rsdp_base, rsdp_size);
517 	if (!rsdp_address) {
518 		return (osl_get_last_status(AE_BAD_ADDRESS));
519 	}
520 
521 	/* Search low memory for the RSDP */
522 
523 	mapped_table = ACPI_CAST_PTR(struct acpi_table_header,
524 				     acpi_tb_scan_memory_for_rsdp(rsdp_address,
525 								  rsdp_size));
526 	if (!mapped_table) {
527 		acpi_os_unmap_memory(rsdp_address, rsdp_size);
528 		return (AE_NOT_FOUND);
529 	}
530 
531 	gbl_rsdp_address =
532 	    rsdp_base + (ACPI_CAST8(mapped_table) - rsdp_address);
533 
534 	memcpy(&gbl_rsdp, mapped_table, sizeof(struct acpi_table_rsdp));
535 	acpi_os_unmap_memory(rsdp_address, rsdp_size);
536 
537 	return (AE_OK);
538 }
539 
540 /******************************************************************************
541  *
542  * FUNCTION:    osl_can_use_xsdt
543  *
544  * PARAMETERS:  None
545  *
546  * RETURN:      TRUE if XSDT is allowed to be used.
547  *
548  * DESCRIPTION: This function collects logic that can be used to determine if
549  *              XSDT should be used instead of RSDT.
550  *
551  *****************************************************************************/
552 
553 static u8 osl_can_use_xsdt(void)
554 {
555 	if (gbl_revision && !acpi_gbl_do_not_use_xsdt) {
556 		return (TRUE);
557 	} else {
558 		return (FALSE);
559 	}
560 }
561 
562 /******************************************************************************
563  *
564  * FUNCTION:    osl_table_initialize
565  *
566  * PARAMETERS:  None
567  *
568  * RETURN:      Status
569  *
570  * DESCRIPTION: Initialize ACPI table data. Get and store main ACPI tables to
571  *              local variables. Main ACPI tables include RSDT, FADT, RSDT,
572  *              and/or XSDT.
573  *
574  *****************************************************************************/
575 
576 static acpi_status osl_table_initialize(void)
577 {
578 	acpi_status status;
579 	acpi_physical_address address;
580 
581 	if (gbl_table_list_initialized) {
582 		return (AE_OK);
583 	}
584 
585 	if (!gbl_dump_customized_tables) {
586 
587 		/* Get RSDP from memory */
588 
589 		status = osl_load_rsdp();
590 		if (ACPI_FAILURE(status)) {
591 			return (status);
592 		}
593 
594 		/* Get XSDT from memory */
595 
596 		if (gbl_rsdp.revision && !gbl_do_not_dump_xsdt) {
597 			if (gbl_xsdt) {
598 				free(gbl_xsdt);
599 				gbl_xsdt = NULL;
600 			}
601 
602 			gbl_revision = 2;
603 			status = osl_get_bios_table(ACPI_SIG_XSDT, 0,
604 						    ACPI_CAST_PTR(struct
605 								  acpi_table_header
606 								  *, &gbl_xsdt),
607 						    &address);
608 			if (ACPI_FAILURE(status)) {
609 				return (status);
610 			}
611 		}
612 
613 		/* Get RSDT from memory */
614 
615 		if (gbl_rsdp.rsdt_physical_address) {
616 			if (gbl_rsdt) {
617 				free(gbl_rsdt);
618 				gbl_rsdt = NULL;
619 			}
620 
621 			status = osl_get_bios_table(ACPI_SIG_RSDT, 0,
622 						    ACPI_CAST_PTR(struct
623 								  acpi_table_header
624 								  *, &gbl_rsdt),
625 						    &address);
626 			if (ACPI_FAILURE(status)) {
627 				return (status);
628 			}
629 		}
630 
631 		/* Get FADT from memory */
632 
633 		if (gbl_fadt) {
634 			free(gbl_fadt);
635 			gbl_fadt = NULL;
636 		}
637 
638 		status = osl_get_bios_table(ACPI_SIG_FADT, 0,
639 					    ACPI_CAST_PTR(struct
640 							  acpi_table_header *,
641 							  &gbl_fadt),
642 					    &gbl_fadt_address);
643 		if (ACPI_FAILURE(status)) {
644 			return (status);
645 		}
646 
647 		/* Add mandatory tables to global table list first */
648 
649 		status = osl_add_table_to_list(ACPI_RSDP_NAME, 0);
650 		if (ACPI_FAILURE(status)) {
651 			return (status);
652 		}
653 
654 		status = osl_add_table_to_list(ACPI_SIG_RSDT, 0);
655 		if (ACPI_FAILURE(status)) {
656 			return (status);
657 		}
658 
659 		if (gbl_revision == 2) {
660 			status = osl_add_table_to_list(ACPI_SIG_XSDT, 0);
661 			if (ACPI_FAILURE(status)) {
662 				return (status);
663 			}
664 		}
665 
666 		status = osl_add_table_to_list(ACPI_SIG_DSDT, 0);
667 		if (ACPI_FAILURE(status)) {
668 			return (status);
669 		}
670 
671 		status = osl_add_table_to_list(ACPI_SIG_FACS, 0);
672 		if (ACPI_FAILURE(status)) {
673 			return (status);
674 		}
675 
676 		/* Add all tables found in the memory */
677 
678 		status = osl_list_bios_tables();
679 		if (ACPI_FAILURE(status)) {
680 			return (status);
681 		}
682 	} else {
683 		/* Add all tables found in the static directory */
684 
685 		status = osl_list_customized_tables(STATIC_TABLE_DIR);
686 		if (ACPI_FAILURE(status)) {
687 			return (status);
688 		}
689 	}
690 
691 	if (gbl_dump_dynamic_tables) {
692 
693 		/* Add all dynamically loaded tables in the dynamic directory */
694 
695 		status = osl_list_customized_tables(DYNAMIC_TABLE_DIR);
696 		if (ACPI_FAILURE(status)) {
697 			return (status);
698 		}
699 	}
700 
701 	gbl_table_list_initialized = TRUE;
702 	return (AE_OK);
703 }
704 
705 /******************************************************************************
706  *
707  * FUNCTION:    osl_list_bios_tables
708  *
709  * PARAMETERS:  None
710  *
711  * RETURN:      Status; Table list is initialized if AE_OK.
712  *
713  * DESCRIPTION: Add ACPI tables to the table list from memory.
714  *
715  * NOTE:        This works on Linux as table customization does not modify the
716  *              addresses stored in RSDP/RSDT/XSDT/FADT.
717  *
718  *****************************************************************************/
719 
720 static acpi_status osl_list_bios_tables(void)
721 {
722 	struct acpi_table_header *mapped_table = NULL;
723 	u8 *table_data;
724 	u8 number_of_tables;
725 	u8 item_size;
726 	acpi_physical_address table_address = 0;
727 	acpi_status status = AE_OK;
728 	u32 i;
729 
730 	if (osl_can_use_xsdt()) {
731 		item_size = sizeof(u64);
732 		table_data =
733 		    ACPI_CAST8(gbl_xsdt) + sizeof(struct acpi_table_header);
734 		number_of_tables =
735 		    (u8)((gbl_xsdt->header.length -
736 			  sizeof(struct acpi_table_header))
737 			 / item_size);
738 	} else {		/* Use RSDT if XSDT is not available */
739 
740 		item_size = sizeof(u32);
741 		table_data =
742 		    ACPI_CAST8(gbl_rsdt) + sizeof(struct acpi_table_header);
743 		number_of_tables =
744 		    (u8)((gbl_rsdt->header.length -
745 			  sizeof(struct acpi_table_header))
746 			 / item_size);
747 	}
748 
749 	/* Search RSDT/XSDT for the requested table */
750 
751 	for (i = 0; i < number_of_tables; ++i, table_data += item_size) {
752 		if (osl_can_use_xsdt()) {
753 			table_address =
754 			    (acpi_physical_address) (*ACPI_CAST64(table_data));
755 		} else {
756 			table_address =
757 			    (acpi_physical_address) (*ACPI_CAST32(table_data));
758 		}
759 
760 		/* Skip NULL entries in RSDT/XSDT */
761 
762 		if (!table_address) {
763 			continue;
764 		}
765 
766 		status = osl_map_table(table_address, NULL, &mapped_table);
767 		if (ACPI_FAILURE(status)) {
768 			return (status);
769 		}
770 
771 		osl_add_table_to_list(mapped_table->signature, 0);
772 		osl_unmap_table(mapped_table);
773 	}
774 
775 	return (AE_OK);
776 }
777 
778 /******************************************************************************
779  *
780  * FUNCTION:    osl_get_bios_table
781  *
782  * PARAMETERS:  signature       - ACPI Signature for common table. Must be
783  *                                a null terminated 4-character string.
784  *              instance        - Multiple table support for SSDT/UEFI (0...n)
785  *                                Must be 0 for other tables.
786  *              table           - Where a pointer to the table is returned
787  *              address         - Where the table physical address is returned
788  *
789  * RETURN:      Status; Table buffer and physical address returned if AE_OK.
790  *              AE_LIMIT: Instance is beyond valid limit
791  *              AE_NOT_FOUND: A table with the signature was not found
792  *
793  * DESCRIPTION: Get a BIOS provided ACPI table
794  *
795  * NOTE:        Assumes the input signature is uppercase.
796  *
797  *****************************************************************************/
798 
799 static acpi_status
800 osl_get_bios_table(char *signature,
801 		   u32 instance,
802 		   struct acpi_table_header **table,
803 		   acpi_physical_address * address)
804 {
805 	struct acpi_table_header *local_table = NULL;
806 	struct acpi_table_header *mapped_table = NULL;
807 	u8 *table_data;
808 	u8 number_of_tables;
809 	u8 item_size;
810 	u32 current_instance = 0;
811 	acpi_physical_address table_address = 0;
812 	u32 table_length = 0;
813 	acpi_status status = AE_OK;
814 	u32 i;
815 
816 	/* Handle special tables whose addresses are not in RSDT/XSDT */
817 
818 	if (ACPI_COMPARE_NAME(signature, ACPI_RSDP_NAME) ||
819 	    ACPI_COMPARE_NAME(signature, ACPI_SIG_RSDT) ||
820 	    ACPI_COMPARE_NAME(signature, ACPI_SIG_XSDT) ||
821 	    ACPI_COMPARE_NAME(signature, ACPI_SIG_DSDT) ||
822 	    ACPI_COMPARE_NAME(signature, ACPI_SIG_FACS)) {
823 		if (instance > 0) {
824 			return (AE_LIMIT);
825 		}
826 
827 		/*
828 		 * Get the appropriate address, either 32-bit or 64-bit. Be very
829 		 * careful about the FADT length and validate table addresses.
830 		 * Note: The 64-bit addresses have priority.
831 		 */
832 		if (ACPI_COMPARE_NAME(signature, ACPI_SIG_DSDT)) {
833 			if ((gbl_fadt->header.length >= MIN_FADT_FOR_XDSDT) &&
834 			    gbl_fadt->Xdsdt) {
835 				table_address =
836 				    (acpi_physical_address) gbl_fadt->Xdsdt;
837 			} else
838 			    if ((gbl_fadt->header.length >= MIN_FADT_FOR_DSDT)
839 				&& gbl_fadt->dsdt) {
840 				table_address =
841 				    (acpi_physical_address) gbl_fadt->dsdt;
842 			}
843 		} else if (ACPI_COMPARE_NAME(signature, ACPI_SIG_FACS)) {
844 			if ((gbl_fadt->header.length >= MIN_FADT_FOR_XFACS) &&
845 			    gbl_fadt->Xfacs) {
846 				table_address =
847 				    (acpi_physical_address) gbl_fadt->Xfacs;
848 			} else
849 			    if ((gbl_fadt->header.length >= MIN_FADT_FOR_FACS)
850 				&& gbl_fadt->facs) {
851 				table_address =
852 				    (acpi_physical_address) gbl_fadt->facs;
853 			}
854 		} else if (ACPI_COMPARE_NAME(signature, ACPI_SIG_XSDT)) {
855 			if (!gbl_revision) {
856 				return (AE_BAD_SIGNATURE);
857 			}
858 			table_address =
859 			    (acpi_physical_address) gbl_rsdp.
860 			    xsdt_physical_address;
861 		} else if (ACPI_COMPARE_NAME(signature, ACPI_SIG_RSDT)) {
862 			table_address =
863 			    (acpi_physical_address) gbl_rsdp.
864 			    rsdt_physical_address;
865 		} else {
866 			table_address =
867 			    (acpi_physical_address) gbl_rsdp_address;
868 			signature = ACPI_SIG_RSDP;
869 		}
870 
871 		/* Now we can get the requested special table */
872 
873 		status = osl_map_table(table_address, signature, &mapped_table);
874 		if (ACPI_FAILURE(status)) {
875 			return (status);
876 		}
877 
878 		table_length = ap_get_table_length(mapped_table);
879 	} else {		/* Case for a normal ACPI table */
880 
881 		if (osl_can_use_xsdt()) {
882 			item_size = sizeof(u64);
883 			table_data =
884 			    ACPI_CAST8(gbl_xsdt) +
885 			    sizeof(struct acpi_table_header);
886 			number_of_tables =
887 			    (u8)((gbl_xsdt->header.length -
888 				  sizeof(struct acpi_table_header))
889 				 / item_size);
890 		} else {	/* Use RSDT if XSDT is not available */
891 
892 			item_size = sizeof(u32);
893 			table_data =
894 			    ACPI_CAST8(gbl_rsdt) +
895 			    sizeof(struct acpi_table_header);
896 			number_of_tables =
897 			    (u8)((gbl_rsdt->header.length -
898 				  sizeof(struct acpi_table_header))
899 				 / item_size);
900 		}
901 
902 		/* Search RSDT/XSDT for the requested table */
903 
904 		for (i = 0; i < number_of_tables; ++i, table_data += item_size) {
905 			if (osl_can_use_xsdt()) {
906 				table_address =
907 				    (acpi_physical_address) (*ACPI_CAST64
908 							     (table_data));
909 			} else {
910 				table_address =
911 				    (acpi_physical_address) (*ACPI_CAST32
912 							     (table_data));
913 			}
914 
915 			/* Skip NULL entries in RSDT/XSDT */
916 
917 			if (!table_address) {
918 				continue;
919 			}
920 
921 			status =
922 			    osl_map_table(table_address, NULL, &mapped_table);
923 			if (ACPI_FAILURE(status)) {
924 				return (status);
925 			}
926 			table_length = mapped_table->length;
927 
928 			/* Does this table match the requested signature? */
929 
930 			if (!ACPI_COMPARE_NAME
931 			    (mapped_table->signature, signature)) {
932 				osl_unmap_table(mapped_table);
933 				mapped_table = NULL;
934 				continue;
935 			}
936 
937 			/* Match table instance (for SSDT/UEFI tables) */
938 
939 			if (current_instance != instance) {
940 				osl_unmap_table(mapped_table);
941 				mapped_table = NULL;
942 				current_instance++;
943 				continue;
944 			}
945 
946 			break;
947 		}
948 	}
949 
950 	if (!mapped_table) {
951 		return (AE_LIMIT);
952 	}
953 
954 	if (table_length == 0) {
955 		status = AE_BAD_HEADER;
956 		goto exit;
957 	}
958 
959 	/* Copy table to local buffer and return it */
960 
961 	local_table = calloc(1, table_length);
962 	if (!local_table) {
963 		status = AE_NO_MEMORY;
964 		goto exit;
965 	}
966 
967 	memcpy(local_table, mapped_table, table_length);
968 	*address = table_address;
969 	*table = local_table;
970 
971 exit:
972 	osl_unmap_table(mapped_table);
973 	return (status);
974 }
975 
976 /******************************************************************************
977  *
978  * FUNCTION:    osl_list_customized_tables
979  *
980  * PARAMETERS:  directory           - Directory that contains the tables
981  *
982  * RETURN:      Status; Table list is initialized if AE_OK.
983  *
984  * DESCRIPTION: Add ACPI tables to the table list from a directory.
985  *
986  *****************************************************************************/
987 
988 static acpi_status osl_list_customized_tables(char *directory)
989 {
990 	void *table_dir;
991 	u32 instance;
992 	char temp_name[ACPI_NAME_SIZE];
993 	char *filename;
994 	acpi_status status = AE_OK;
995 
996 	/* Open the requested directory */
997 
998 	table_dir = acpi_os_open_directory(directory, "*", REQUEST_FILE_ONLY);
999 	if (!table_dir) {
1000 		return (osl_get_last_status(AE_NOT_FOUND));
1001 	}
1002 
1003 	/* Examine all entries in this directory */
1004 
1005 	while ((filename = acpi_os_get_next_filename(table_dir))) {
1006 
1007 		/* Extract table name and instance number */
1008 
1009 		status =
1010 		    osl_table_name_from_file(filename, temp_name, &instance);
1011 
1012 		/* Ignore meaningless files */
1013 
1014 		if (ACPI_FAILURE(status)) {
1015 			continue;
1016 		}
1017 
1018 		/* Add new info node to global table list */
1019 
1020 		status = osl_add_table_to_list(temp_name, instance);
1021 		if (ACPI_FAILURE(status)) {
1022 			break;
1023 		}
1024 	}
1025 
1026 	acpi_os_close_directory(table_dir);
1027 	return (status);
1028 }
1029 
1030 /******************************************************************************
1031  *
1032  * FUNCTION:    osl_map_table
1033  *
1034  * PARAMETERS:  address             - Address of the table in memory
1035  *              signature           - Optional ACPI Signature for desired table.
1036  *                                    Null terminated 4-character string.
1037  *              table               - Where a pointer to the mapped table is
1038  *                                    returned
1039  *
1040  * RETURN:      Status; Mapped table is returned if AE_OK.
1041  *              AE_NOT_FOUND: A valid table was not found at the address
1042  *
1043  * DESCRIPTION: Map entire ACPI table into caller's address space.
1044  *
1045  *****************************************************************************/
1046 
1047 static acpi_status
1048 osl_map_table(acpi_size address,
1049 	      char *signature, struct acpi_table_header **table)
1050 {
1051 	struct acpi_table_header *mapped_table;
1052 	u32 length;
1053 
1054 	if (!address) {
1055 		return (AE_BAD_ADDRESS);
1056 	}
1057 
1058 	/*
1059 	 * Map the header so we can get the table length.
1060 	 * Use sizeof (struct acpi_table_header) as:
1061 	 * 1. it is bigger than 24 to include RSDP->Length
1062 	 * 2. it is smaller than sizeof (struct acpi_table_rsdp)
1063 	 */
1064 	mapped_table =
1065 	    acpi_os_map_memory(address, sizeof(struct acpi_table_header));
1066 	if (!mapped_table) {
1067 		fprintf(stderr, "Could not map table header at 0x%8.8X%8.8X\n",
1068 			ACPI_FORMAT_UINT64(address));
1069 		return (osl_get_last_status(AE_BAD_ADDRESS));
1070 	}
1071 
1072 	/* If specified, signature must match */
1073 
1074 	if (signature) {
1075 		if (ACPI_VALIDATE_RSDP_SIG(signature)) {
1076 			if (!ACPI_VALIDATE_RSDP_SIG(mapped_table->signature)) {
1077 				acpi_os_unmap_memory(mapped_table,
1078 						     sizeof(struct
1079 							    acpi_table_header));
1080 				return (AE_BAD_SIGNATURE);
1081 			}
1082 		} else
1083 		    if (!ACPI_COMPARE_NAME(signature, mapped_table->signature))
1084 		{
1085 			acpi_os_unmap_memory(mapped_table,
1086 					     sizeof(struct acpi_table_header));
1087 			return (AE_BAD_SIGNATURE);
1088 		}
1089 	}
1090 
1091 	/* Map the entire table */
1092 
1093 	length = ap_get_table_length(mapped_table);
1094 	acpi_os_unmap_memory(mapped_table, sizeof(struct acpi_table_header));
1095 	if (length == 0) {
1096 		return (AE_BAD_HEADER);
1097 	}
1098 
1099 	mapped_table = acpi_os_map_memory(address, length);
1100 	if (!mapped_table) {
1101 		fprintf(stderr,
1102 			"Could not map table at 0x%8.8X%8.8X length %8.8X\n",
1103 			ACPI_FORMAT_UINT64(address), length);
1104 		return (osl_get_last_status(AE_INVALID_TABLE_LENGTH));
1105 	}
1106 
1107 	(void)ap_is_valid_checksum(mapped_table);
1108 
1109 	*table = mapped_table;
1110 	return (AE_OK);
1111 }
1112 
1113 /******************************************************************************
1114  *
1115  * FUNCTION:    osl_unmap_table
1116  *
1117  * PARAMETERS:  table               - A pointer to the mapped table
1118  *
1119  * RETURN:      None
1120  *
1121  * DESCRIPTION: Unmap entire ACPI table.
1122  *
1123  *****************************************************************************/
1124 
1125 static void osl_unmap_table(struct acpi_table_header *table)
1126 {
1127 	if (table) {
1128 		acpi_os_unmap_memory(table, ap_get_table_length(table));
1129 	}
1130 }
1131 
1132 /******************************************************************************
1133  *
1134  * FUNCTION:    osl_table_name_from_file
1135  *
1136  * PARAMETERS:  filename            - File that contains the desired table
1137  *              signature           - Pointer to 4-character buffer to store
1138  *                                    extracted table signature.
1139  *              instance            - Pointer to integer to store extracted
1140  *                                    table instance number.
1141  *
1142  * RETURN:      Status; Table name is extracted if AE_OK.
1143  *
1144  * DESCRIPTION: Extract table signature and instance number from a table file
1145  *              name.
1146  *
1147  *****************************************************************************/
1148 
1149 static acpi_status
1150 osl_table_name_from_file(char *filename, char *signature, u32 *instance)
1151 {
1152 
1153 	/* Ignore meaningless files */
1154 
1155 	if (strlen(filename) < ACPI_NAME_SIZE) {
1156 		return (AE_BAD_SIGNATURE);
1157 	}
1158 
1159 	/* Extract instance number */
1160 
1161 	if (isdigit((int)filename[ACPI_NAME_SIZE])) {
1162 		sscanf(&filename[ACPI_NAME_SIZE], "%u", instance);
1163 	} else if (strlen(filename) != ACPI_NAME_SIZE) {
1164 		return (AE_BAD_SIGNATURE);
1165 	} else {
1166 		*instance = 0;
1167 	}
1168 
1169 	/* Extract signature */
1170 
1171 	ACPI_MOVE_NAME(signature, filename);
1172 	return (AE_OK);
1173 }
1174 
1175 /******************************************************************************
1176  *
1177  * FUNCTION:    osl_read_table_from_file
1178  *
1179  * PARAMETERS:  filename            - File that contains the desired table
1180  *              file_offset         - Offset of the table in file
1181  *              signature           - Optional ACPI Signature for desired table.
1182  *                                    A null terminated 4-character string.
1183  *              table               - Where a pointer to the table is returned
1184  *
1185  * RETURN:      Status; Table buffer is returned if AE_OK.
1186  *
1187  * DESCRIPTION: Read a ACPI table from a file.
1188  *
1189  *****************************************************************************/
1190 
1191 static acpi_status
1192 osl_read_table_from_file(char *filename,
1193 			 acpi_size file_offset,
1194 			 char *signature, struct acpi_table_header **table)
1195 {
1196 	FILE *table_file;
1197 	struct acpi_table_header header;
1198 	struct acpi_table_header *local_table = NULL;
1199 	u32 table_length;
1200 	s32 count;
1201 	acpi_status status = AE_OK;
1202 
1203 	/* Open the file */
1204 
1205 	table_file = fopen(filename, "rb");
1206 	if (table_file == NULL) {
1207 		fprintf(stderr, "Could not open table file: %s\n", filename);
1208 		return (osl_get_last_status(AE_NOT_FOUND));
1209 	}
1210 
1211 	fseek(table_file, file_offset, SEEK_SET);
1212 
1213 	/* Read the Table header to get the table length */
1214 
1215 	count = fread(&header, 1, sizeof(struct acpi_table_header), table_file);
1216 	if (count != sizeof(struct acpi_table_header)) {
1217 		fprintf(stderr, "Could not read table header: %s\n", filename);
1218 		status = AE_BAD_HEADER;
1219 		goto exit;
1220 	}
1221 
1222 	/* If signature is specified, it must match the table */
1223 
1224 	if (signature) {
1225 		if (ACPI_VALIDATE_RSDP_SIG(signature)) {
1226 			if (!ACPI_VALIDATE_RSDP_SIG(header.signature)) {
1227 				fprintf(stderr,
1228 					"Incorrect RSDP signature: found %8.8s\n",
1229 					header.signature);
1230 				status = AE_BAD_SIGNATURE;
1231 				goto exit;
1232 			}
1233 		} else if (!ACPI_COMPARE_NAME(signature, header.signature)) {
1234 			fprintf(stderr,
1235 				"Incorrect signature: Expecting %4.4s, found %4.4s\n",
1236 				signature, header.signature);
1237 			status = AE_BAD_SIGNATURE;
1238 			goto exit;
1239 		}
1240 	}
1241 
1242 	table_length = ap_get_table_length(&header);
1243 	if (table_length == 0) {
1244 		status = AE_BAD_HEADER;
1245 		goto exit;
1246 	}
1247 
1248 	/* Read the entire table into a local buffer */
1249 
1250 	local_table = calloc(1, table_length);
1251 	if (!local_table) {
1252 		fprintf(stderr,
1253 			"%4.4s: Could not allocate buffer for table of length %X\n",
1254 			header.signature, table_length);
1255 		status = AE_NO_MEMORY;
1256 		goto exit;
1257 	}
1258 
1259 	fseek(table_file, file_offset, SEEK_SET);
1260 
1261 	count = fread(local_table, 1, table_length, table_file);
1262 	if (count != table_length) {
1263 		fprintf(stderr, "%4.4s: Could not read table content\n",
1264 			header.signature);
1265 		status = AE_INVALID_TABLE_LENGTH;
1266 		goto exit;
1267 	}
1268 
1269 	/* Validate checksum */
1270 
1271 	(void)ap_is_valid_checksum(local_table);
1272 
1273 exit:
1274 	fclose(table_file);
1275 	*table = local_table;
1276 	return (status);
1277 }
1278 
1279 /******************************************************************************
1280  *
1281  * FUNCTION:    osl_get_customized_table
1282  *
1283  * PARAMETERS:  pathname        - Directory to find Linux customized table
1284  *              signature       - ACPI Signature for desired table. Must be
1285  *                                a null terminated 4-character string.
1286  *              instance        - Multiple table support for SSDT/UEFI (0...n)
1287  *                                Must be 0 for other tables.
1288  *              table           - Where a pointer to the table is returned
1289  *              address         - Where the table physical address is returned
1290  *
1291  * RETURN:      Status; Table buffer is returned if AE_OK.
1292  *              AE_LIMIT: Instance is beyond valid limit
1293  *              AE_NOT_FOUND: A table with the signature was not found
1294  *
1295  * DESCRIPTION: Get an OS customized table.
1296  *
1297  *****************************************************************************/
1298 
1299 static acpi_status
1300 osl_get_customized_table(char *pathname,
1301 			 char *signature,
1302 			 u32 instance,
1303 			 struct acpi_table_header **table,
1304 			 acpi_physical_address * address)
1305 {
1306 	void *table_dir;
1307 	u32 current_instance = 0;
1308 	char temp_name[ACPI_NAME_SIZE];
1309 	char table_filename[PATH_MAX];
1310 	char *filename;
1311 	acpi_status status;
1312 
1313 	/* Open the directory for customized tables */
1314 
1315 	table_dir = acpi_os_open_directory(pathname, "*", REQUEST_FILE_ONLY);
1316 	if (!table_dir) {
1317 		return (osl_get_last_status(AE_NOT_FOUND));
1318 	}
1319 
1320 	/* Attempt to find the table in the directory */
1321 
1322 	while ((filename = acpi_os_get_next_filename(table_dir))) {
1323 
1324 		/* Ignore meaningless files */
1325 
1326 		if (!ACPI_COMPARE_NAME(filename, signature)) {
1327 			continue;
1328 		}
1329 
1330 		/* Extract table name and instance number */
1331 
1332 		status =
1333 		    osl_table_name_from_file(filename, temp_name,
1334 					     &current_instance);
1335 
1336 		/* Ignore meaningless files */
1337 
1338 		if (ACPI_FAILURE(status) || current_instance != instance) {
1339 			continue;
1340 		}
1341 
1342 		/* Create the table pathname */
1343 
1344 		if (instance != 0) {
1345 			sprintf(table_filename, "%s/%4.4s%d", pathname,
1346 				temp_name, instance);
1347 		} else {
1348 			sprintf(table_filename, "%s/%4.4s", pathname,
1349 				temp_name);
1350 		}
1351 		break;
1352 	}
1353 
1354 	acpi_os_close_directory(table_dir);
1355 
1356 	if (!filename) {
1357 		return (AE_LIMIT);
1358 	}
1359 
1360 	/* There is no physical address saved for customized tables, use zero */
1361 
1362 	*address = 0;
1363 	status = osl_read_table_from_file(table_filename, 0, NULL, table);
1364 
1365 	return (status);
1366 }
1367