xref: /linux/tools/power/acpi/os_specific/service_layers/oslinuxtbl.c (revision e5c86679d5e864947a52fb31e45a425dea3e7fa9)
1 /******************************************************************************
2  *
3  * Module Name: oslinuxtbl - Linux OSL for obtaining ACPI tables
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2017, 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 = (acpi_physical_address)gbl_rsdp_address;
867 			signature = ACPI_SIG_RSDP;
868 		}
869 
870 		/* Now we can get the requested special table */
871 
872 		status = osl_map_table(table_address, signature, &mapped_table);
873 		if (ACPI_FAILURE(status)) {
874 			return (status);
875 		}
876 
877 		table_length = ap_get_table_length(mapped_table);
878 	} else {		/* Case for a normal ACPI table */
879 
880 		if (osl_can_use_xsdt()) {
881 			item_size = sizeof(u64);
882 			table_data =
883 			    ACPI_CAST8(gbl_xsdt) +
884 			    sizeof(struct acpi_table_header);
885 			number_of_tables =
886 			    (u8)((gbl_xsdt->header.length -
887 				  sizeof(struct acpi_table_header))
888 				 / item_size);
889 		} else {	/* Use RSDT if XSDT is not available */
890 
891 			item_size = sizeof(u32);
892 			table_data =
893 			    ACPI_CAST8(gbl_rsdt) +
894 			    sizeof(struct acpi_table_header);
895 			number_of_tables =
896 			    (u8)((gbl_rsdt->header.length -
897 				  sizeof(struct acpi_table_header))
898 				 / item_size);
899 		}
900 
901 		/* Search RSDT/XSDT for the requested table */
902 
903 		for (i = 0; i < number_of_tables; ++i, table_data += item_size) {
904 			if (osl_can_use_xsdt()) {
905 				table_address =
906 				    (acpi_physical_address)(*ACPI_CAST64
907 							    (table_data));
908 			} else {
909 				table_address =
910 				    (acpi_physical_address)(*ACPI_CAST32
911 							    (table_data));
912 			}
913 
914 			/* Skip NULL entries in RSDT/XSDT */
915 
916 			if (!table_address) {
917 				continue;
918 			}
919 
920 			status =
921 			    osl_map_table(table_address, NULL, &mapped_table);
922 			if (ACPI_FAILURE(status)) {
923 				return (status);
924 			}
925 			table_length = mapped_table->length;
926 
927 			/* Does this table match the requested signature? */
928 
929 			if (!ACPI_COMPARE_NAME
930 			    (mapped_table->signature, signature)) {
931 				osl_unmap_table(mapped_table);
932 				mapped_table = NULL;
933 				continue;
934 			}
935 
936 			/* Match table instance (for SSDT/UEFI tables) */
937 
938 			if (current_instance != instance) {
939 				osl_unmap_table(mapped_table);
940 				mapped_table = NULL;
941 				current_instance++;
942 				continue;
943 			}
944 
945 			break;
946 		}
947 	}
948 
949 	if (!mapped_table) {
950 		return (AE_LIMIT);
951 	}
952 
953 	if (table_length == 0) {
954 		status = AE_BAD_HEADER;
955 		goto exit;
956 	}
957 
958 	/* Copy table to local buffer and return it */
959 
960 	local_table = calloc(1, table_length);
961 	if (!local_table) {
962 		status = AE_NO_MEMORY;
963 		goto exit;
964 	}
965 
966 	memcpy(local_table, mapped_table, table_length);
967 	*address = table_address;
968 	*table = local_table;
969 
970 exit:
971 	osl_unmap_table(mapped_table);
972 	return (status);
973 }
974 
975 /******************************************************************************
976  *
977  * FUNCTION:    osl_list_customized_tables
978  *
979  * PARAMETERS:  directory           - Directory that contains the tables
980  *
981  * RETURN:      Status; Table list is initialized if AE_OK.
982  *
983  * DESCRIPTION: Add ACPI tables to the table list from a directory.
984  *
985  *****************************************************************************/
986 
987 static acpi_status osl_list_customized_tables(char *directory)
988 {
989 	void *table_dir;
990 	u32 instance;
991 	char temp_name[ACPI_NAME_SIZE];
992 	char *filename;
993 	acpi_status status = AE_OK;
994 
995 	/* Open the requested directory */
996 
997 	table_dir = acpi_os_open_directory(directory, "*", REQUEST_FILE_ONLY);
998 	if (!table_dir) {
999 		return (osl_get_last_status(AE_NOT_FOUND));
1000 	}
1001 
1002 	/* Examine all entries in this directory */
1003 
1004 	while ((filename = acpi_os_get_next_filename(table_dir))) {
1005 
1006 		/* Extract table name and instance number */
1007 
1008 		status =
1009 		    osl_table_name_from_file(filename, temp_name, &instance);
1010 
1011 		/* Ignore meaningless files */
1012 
1013 		if (ACPI_FAILURE(status)) {
1014 			continue;
1015 		}
1016 
1017 		/* Add new info node to global table list */
1018 
1019 		status = osl_add_table_to_list(temp_name, instance);
1020 		if (ACPI_FAILURE(status)) {
1021 			break;
1022 		}
1023 	}
1024 
1025 	acpi_os_close_directory(table_dir);
1026 	return (status);
1027 }
1028 
1029 /******************************************************************************
1030  *
1031  * FUNCTION:    osl_map_table
1032  *
1033  * PARAMETERS:  address             - Address of the table in memory
1034  *              signature           - Optional ACPI Signature for desired table.
1035  *                                    Null terminated 4-character string.
1036  *              table               - Where a pointer to the mapped table is
1037  *                                    returned
1038  *
1039  * RETURN:      Status; Mapped table is returned if AE_OK.
1040  *              AE_NOT_FOUND: A valid table was not found at the address
1041  *
1042  * DESCRIPTION: Map entire ACPI table into caller's address space.
1043  *
1044  *****************************************************************************/
1045 
1046 static acpi_status
1047 osl_map_table(acpi_size address,
1048 	      char *signature, struct acpi_table_header **table)
1049 {
1050 	struct acpi_table_header *mapped_table;
1051 	u32 length;
1052 
1053 	if (!address) {
1054 		return (AE_BAD_ADDRESS);
1055 	}
1056 
1057 	/*
1058 	 * Map the header so we can get the table length.
1059 	 * Use sizeof (struct acpi_table_header) as:
1060 	 * 1. it is bigger than 24 to include RSDP->Length
1061 	 * 2. it is smaller than sizeof (struct acpi_table_rsdp)
1062 	 */
1063 	mapped_table =
1064 	    acpi_os_map_memory(address, sizeof(struct acpi_table_header));
1065 	if (!mapped_table) {
1066 		fprintf(stderr, "Could not map table header at 0x%8.8X%8.8X\n",
1067 			ACPI_FORMAT_UINT64(address));
1068 		return (osl_get_last_status(AE_BAD_ADDRESS));
1069 	}
1070 
1071 	/* If specified, signature must match */
1072 
1073 	if (signature) {
1074 		if (ACPI_VALIDATE_RSDP_SIG(signature)) {
1075 			if (!ACPI_VALIDATE_RSDP_SIG(mapped_table->signature)) {
1076 				acpi_os_unmap_memory(mapped_table,
1077 						     sizeof(struct
1078 							    acpi_table_header));
1079 				return (AE_BAD_SIGNATURE);
1080 			}
1081 		} else
1082 		    if (!ACPI_COMPARE_NAME(signature, mapped_table->signature))
1083 		{
1084 			acpi_os_unmap_memory(mapped_table,
1085 					     sizeof(struct acpi_table_header));
1086 			return (AE_BAD_SIGNATURE);
1087 		}
1088 	}
1089 
1090 	/* Map the entire table */
1091 
1092 	length = ap_get_table_length(mapped_table);
1093 	acpi_os_unmap_memory(mapped_table, sizeof(struct acpi_table_header));
1094 	if (length == 0) {
1095 		return (AE_BAD_HEADER);
1096 	}
1097 
1098 	mapped_table = acpi_os_map_memory(address, length);
1099 	if (!mapped_table) {
1100 		fprintf(stderr,
1101 			"Could not map table at 0x%8.8X%8.8X length %8.8X\n",
1102 			ACPI_FORMAT_UINT64(address), length);
1103 		return (osl_get_last_status(AE_INVALID_TABLE_LENGTH));
1104 	}
1105 
1106 	(void)ap_is_valid_checksum(mapped_table);
1107 
1108 	*table = mapped_table;
1109 	return (AE_OK);
1110 }
1111 
1112 /******************************************************************************
1113  *
1114  * FUNCTION:    osl_unmap_table
1115  *
1116  * PARAMETERS:  table               - A pointer to the mapped table
1117  *
1118  * RETURN:      None
1119  *
1120  * DESCRIPTION: Unmap entire ACPI table.
1121  *
1122  *****************************************************************************/
1123 
1124 static void osl_unmap_table(struct acpi_table_header *table)
1125 {
1126 	if (table) {
1127 		acpi_os_unmap_memory(table, ap_get_table_length(table));
1128 	}
1129 }
1130 
1131 /******************************************************************************
1132  *
1133  * FUNCTION:    osl_table_name_from_file
1134  *
1135  * PARAMETERS:  filename            - File that contains the desired table
1136  *              signature           - Pointer to 4-character buffer to store
1137  *                                    extracted table signature.
1138  *              instance            - Pointer to integer to store extracted
1139  *                                    table instance number.
1140  *
1141  * RETURN:      Status; Table name is extracted if AE_OK.
1142  *
1143  * DESCRIPTION: Extract table signature and instance number from a table file
1144  *              name.
1145  *
1146  *****************************************************************************/
1147 
1148 static acpi_status
1149 osl_table_name_from_file(char *filename, char *signature, u32 *instance)
1150 {
1151 
1152 	/* Ignore meaningless files */
1153 
1154 	if (strlen(filename) < ACPI_NAME_SIZE) {
1155 		return (AE_BAD_SIGNATURE);
1156 	}
1157 
1158 	/* Extract instance number */
1159 
1160 	if (isdigit((int)filename[ACPI_NAME_SIZE])) {
1161 		sscanf(&filename[ACPI_NAME_SIZE], "%u", instance);
1162 	} else if (strlen(filename) != ACPI_NAME_SIZE) {
1163 		return (AE_BAD_SIGNATURE);
1164 	} else {
1165 		*instance = 0;
1166 	}
1167 
1168 	/* Extract signature */
1169 
1170 	ACPI_MOVE_NAME(signature, filename);
1171 	return (AE_OK);
1172 }
1173 
1174 /******************************************************************************
1175  *
1176  * FUNCTION:    osl_read_table_from_file
1177  *
1178  * PARAMETERS:  filename            - File that contains the desired table
1179  *              file_offset         - Offset of the table in file
1180  *              signature           - Optional ACPI Signature for desired table.
1181  *                                    A null terminated 4-character string.
1182  *              table               - Where a pointer to the table is returned
1183  *
1184  * RETURN:      Status; Table buffer is returned if AE_OK.
1185  *
1186  * DESCRIPTION: Read a ACPI table from a file.
1187  *
1188  *****************************************************************************/
1189 
1190 static acpi_status
1191 osl_read_table_from_file(char *filename,
1192 			 acpi_size file_offset,
1193 			 char *signature, struct acpi_table_header **table)
1194 {
1195 	FILE *table_file;
1196 	struct acpi_table_header header;
1197 	struct acpi_table_header *local_table = NULL;
1198 	u32 table_length;
1199 	s32 count;
1200 	acpi_status status = AE_OK;
1201 
1202 	/* Open the file */
1203 
1204 	table_file = fopen(filename, "rb");
1205 	if (table_file == NULL) {
1206 		fprintf(stderr, "Could not open table file: %s\n", filename);
1207 		return (osl_get_last_status(AE_NOT_FOUND));
1208 	}
1209 
1210 	fseek(table_file, file_offset, SEEK_SET);
1211 
1212 	/* Read the Table header to get the table length */
1213 
1214 	count = fread(&header, 1, sizeof(struct acpi_table_header), table_file);
1215 	if (count != sizeof(struct acpi_table_header)) {
1216 		fprintf(stderr, "Could not read table header: %s\n", filename);
1217 		status = AE_BAD_HEADER;
1218 		goto exit;
1219 	}
1220 
1221 	/* If signature is specified, it must match the table */
1222 
1223 	if (signature) {
1224 		if (ACPI_VALIDATE_RSDP_SIG(signature)) {
1225 			if (!ACPI_VALIDATE_RSDP_SIG(header.signature)) {
1226 				fprintf(stderr,
1227 					"Incorrect RSDP signature: found %8.8s\n",
1228 					header.signature);
1229 				status = AE_BAD_SIGNATURE;
1230 				goto exit;
1231 			}
1232 		} else if (!ACPI_COMPARE_NAME(signature, header.signature)) {
1233 			fprintf(stderr,
1234 				"Incorrect signature: Expecting %4.4s, found %4.4s\n",
1235 				signature, header.signature);
1236 			status = AE_BAD_SIGNATURE;
1237 			goto exit;
1238 		}
1239 	}
1240 
1241 	table_length = ap_get_table_length(&header);
1242 	if (table_length == 0) {
1243 		status = AE_BAD_HEADER;
1244 		goto exit;
1245 	}
1246 
1247 	/* Read the entire table into a local buffer */
1248 
1249 	local_table = calloc(1, table_length);
1250 	if (!local_table) {
1251 		fprintf(stderr,
1252 			"%4.4s: Could not allocate buffer for table of length %X\n",
1253 			header.signature, table_length);
1254 		status = AE_NO_MEMORY;
1255 		goto exit;
1256 	}
1257 
1258 	fseek(table_file, file_offset, SEEK_SET);
1259 
1260 	count = fread(local_table, 1, table_length, table_file);
1261 	if (count != table_length) {
1262 		fprintf(stderr, "%4.4s: Could not read table content\n",
1263 			header.signature);
1264 		status = AE_INVALID_TABLE_LENGTH;
1265 		goto exit;
1266 	}
1267 
1268 	/* Validate checksum */
1269 
1270 	(void)ap_is_valid_checksum(local_table);
1271 
1272 exit:
1273 	fclose(table_file);
1274 	*table = local_table;
1275 	return (status);
1276 }
1277 
1278 /******************************************************************************
1279  *
1280  * FUNCTION:    osl_get_customized_table
1281  *
1282  * PARAMETERS:  pathname        - Directory to find Linux customized table
1283  *              signature       - ACPI Signature for desired table. Must be
1284  *                                a null terminated 4-character string.
1285  *              instance        - Multiple table support for SSDT/UEFI (0...n)
1286  *                                Must be 0 for other tables.
1287  *              table           - Where a pointer to the table is returned
1288  *              address         - Where the table physical address is returned
1289  *
1290  * RETURN:      Status; Table buffer is returned if AE_OK.
1291  *              AE_LIMIT: Instance is beyond valid limit
1292  *              AE_NOT_FOUND: A table with the signature was not found
1293  *
1294  * DESCRIPTION: Get an OS customized table.
1295  *
1296  *****************************************************************************/
1297 
1298 static acpi_status
1299 osl_get_customized_table(char *pathname,
1300 			 char *signature,
1301 			 u32 instance,
1302 			 struct acpi_table_header **table,
1303 			 acpi_physical_address *address)
1304 {
1305 	void *table_dir;
1306 	u32 current_instance = 0;
1307 	char temp_name[ACPI_NAME_SIZE];
1308 	char table_filename[PATH_MAX];
1309 	char *filename;
1310 	acpi_status status;
1311 
1312 	/* Open the directory for customized tables */
1313 
1314 	table_dir = acpi_os_open_directory(pathname, "*", REQUEST_FILE_ONLY);
1315 	if (!table_dir) {
1316 		return (osl_get_last_status(AE_NOT_FOUND));
1317 	}
1318 
1319 	/* Attempt to find the table in the directory */
1320 
1321 	while ((filename = acpi_os_get_next_filename(table_dir))) {
1322 
1323 		/* Ignore meaningless files */
1324 
1325 		if (!ACPI_COMPARE_NAME(filename, signature)) {
1326 			continue;
1327 		}
1328 
1329 		/* Extract table name and instance number */
1330 
1331 		status =
1332 		    osl_table_name_from_file(filename, temp_name,
1333 					     &current_instance);
1334 
1335 		/* Ignore meaningless files */
1336 
1337 		if (ACPI_FAILURE(status) || current_instance != instance) {
1338 			continue;
1339 		}
1340 
1341 		/* Create the table pathname */
1342 
1343 		if (instance != 0) {
1344 			sprintf(table_filename, "%s/%4.4s%d", pathname,
1345 				temp_name, instance);
1346 		} else {
1347 			sprintf(table_filename, "%s/%4.4s", pathname,
1348 				temp_name);
1349 		}
1350 		break;
1351 	}
1352 
1353 	acpi_os_close_directory(table_dir);
1354 
1355 	if (!filename) {
1356 		return (AE_LIMIT);
1357 	}
1358 
1359 	/* There is no physical address saved for customized tables, use zero */
1360 
1361 	*address = 0;
1362 	status = osl_read_table_from_file(table_filename, 0, NULL, table);
1363 
1364 	return (status);
1365 }
1366