xref: /openbmc/linux/drivers/acpi/acpica/tbutils.c (revision afc98d90)
1 /******************************************************************************
2  *
3  * Module Name: tbutils - ACPI Table utilities
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2013, 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 acpi_status acpi_tb_validate_xsdt(acpi_physical_address address);
53 
54 static acpi_physical_address
55 acpi_tb_get_root_table_entry(u8 *table_entry, u32 table_entry_size);
56 
57 #if (!ACPI_REDUCED_HARDWARE)
58 /*******************************************************************************
59  *
60  * FUNCTION:    acpi_tb_initialize_facs
61  *
62  * PARAMETERS:  None
63  *
64  * RETURN:      Status
65  *
66  * DESCRIPTION: Create a permanent mapping for the FADT and save it in a global
67  *              for accessing the Global Lock and Firmware Waking Vector
68  *
69  ******************************************************************************/
70 
71 acpi_status acpi_tb_initialize_facs(void)
72 {
73 	acpi_status status;
74 
75 	/* If Hardware Reduced flag is set, there is no FACS */
76 
77 	if (acpi_gbl_reduced_hardware) {
78 		acpi_gbl_FACS = NULL;
79 		return (AE_OK);
80 	}
81 
82 	status = acpi_get_table_by_index(ACPI_TABLE_INDEX_FACS,
83 					 ACPI_CAST_INDIRECT_PTR(struct
84 								acpi_table_header,
85 								&acpi_gbl_FACS));
86 	return (status);
87 }
88 #endif				/* !ACPI_REDUCED_HARDWARE */
89 
90 /*******************************************************************************
91  *
92  * FUNCTION:    acpi_tb_tables_loaded
93  *
94  * PARAMETERS:  None
95  *
96  * RETURN:      TRUE if required ACPI tables are loaded
97  *
98  * DESCRIPTION: Determine if the minimum required ACPI tables are present
99  *              (FADT, FACS, DSDT)
100  *
101  ******************************************************************************/
102 
103 u8 acpi_tb_tables_loaded(void)
104 {
105 
106 	if (acpi_gbl_root_table_list.current_table_count >= 3) {
107 		return (TRUE);
108 	}
109 
110 	return (FALSE);
111 }
112 
113 /*******************************************************************************
114  *
115  * FUNCTION:    acpi_tb_check_dsdt_header
116  *
117  * PARAMETERS:  None
118  *
119  * RETURN:      None
120  *
121  * DESCRIPTION: Quick compare to check validity of the DSDT. This will detect
122  *              if the DSDT has been replaced from outside the OS and/or if
123  *              the DSDT header has been corrupted.
124  *
125  ******************************************************************************/
126 
127 void acpi_tb_check_dsdt_header(void)
128 {
129 
130 	/* Compare original length and checksum to current values */
131 
132 	if (acpi_gbl_original_dsdt_header.length != acpi_gbl_DSDT->length ||
133 	    acpi_gbl_original_dsdt_header.checksum != acpi_gbl_DSDT->checksum) {
134 		ACPI_BIOS_ERROR((AE_INFO,
135 				 "The DSDT has been corrupted or replaced - "
136 				 "old, new headers below"));
137 		acpi_tb_print_table_header(0, &acpi_gbl_original_dsdt_header);
138 		acpi_tb_print_table_header(0, acpi_gbl_DSDT);
139 
140 		ACPI_ERROR((AE_INFO,
141 			    "Please send DMI info to linux-acpi@vger.kernel.org\n"
142 			    "If system does not work as expected, please boot with acpi=copy_dsdt"));
143 
144 		/* Disable further error messages */
145 
146 		acpi_gbl_original_dsdt_header.length = acpi_gbl_DSDT->length;
147 		acpi_gbl_original_dsdt_header.checksum =
148 		    acpi_gbl_DSDT->checksum;
149 	}
150 }
151 
152 /*******************************************************************************
153  *
154  * FUNCTION:    acpi_tb_copy_dsdt
155  *
156  * PARAMETERS:  table_desc          - Installed table to copy
157  *
158  * RETURN:      None
159  *
160  * DESCRIPTION: Implements a subsystem option to copy the DSDT to local memory.
161  *              Some very bad BIOSs are known to either corrupt the DSDT or
162  *              install a new, bad DSDT. This copy works around the problem.
163  *
164  ******************************************************************************/
165 
166 struct acpi_table_header *acpi_tb_copy_dsdt(u32 table_index)
167 {
168 	struct acpi_table_header *new_table;
169 	struct acpi_table_desc *table_desc;
170 
171 	table_desc = &acpi_gbl_root_table_list.tables[table_index];
172 
173 	new_table = ACPI_ALLOCATE(table_desc->length);
174 	if (!new_table) {
175 		ACPI_ERROR((AE_INFO, "Could not copy DSDT of length 0x%X",
176 			    table_desc->length));
177 		return (NULL);
178 	}
179 
180 	ACPI_MEMCPY(new_table, table_desc->pointer, table_desc->length);
181 	acpi_tb_delete_table(table_desc);
182 	table_desc->pointer = new_table;
183 	table_desc->flags = ACPI_TABLE_ORIGIN_ALLOCATED;
184 
185 	ACPI_INFO((AE_INFO,
186 		   "Forced DSDT copy: length 0x%05X copied locally, original unmapped",
187 		   new_table->length));
188 
189 	return (new_table);
190 }
191 
192 /*******************************************************************************
193  *
194  * FUNCTION:    acpi_tb_install_table
195  *
196  * PARAMETERS:  address                 - Physical address of DSDT or FACS
197  *              signature               - Table signature, NULL if no need to
198  *                                        match
199  *              table_index             - Index into root table array
200  *
201  * RETURN:      None
202  *
203  * DESCRIPTION: Install an ACPI table into the global data structure. The
204  *              table override mechanism is called to allow the host
205  *              OS to replace any table before it is installed in the root
206  *              table array.
207  *
208  ******************************************************************************/
209 
210 void
211 acpi_tb_install_table(acpi_physical_address address,
212 		      char *signature, u32 table_index)
213 {
214 	struct acpi_table_header *table;
215 	struct acpi_table_header *final_table;
216 	struct acpi_table_desc *table_desc;
217 
218 	if (!address) {
219 		ACPI_ERROR((AE_INFO,
220 			    "Null physical address for ACPI table [%s]",
221 			    signature));
222 		return;
223 	}
224 
225 	/* Map just the table header */
226 
227 	table = acpi_os_map_memory(address, sizeof(struct acpi_table_header));
228 	if (!table) {
229 		ACPI_ERROR((AE_INFO,
230 			    "Could not map memory for table [%s] at %p",
231 			    signature, ACPI_CAST_PTR(void, address)));
232 		return;
233 	}
234 
235 	/* If a particular signature is expected (DSDT/FACS), it must match */
236 
237 	if (signature && !ACPI_COMPARE_NAME(table->signature, signature)) {
238 		ACPI_BIOS_ERROR((AE_INFO,
239 				 "Invalid signature 0x%X for ACPI table, expected [%s]",
240 				 *ACPI_CAST_PTR(u32, table->signature),
241 				 signature));
242 		goto unmap_and_exit;
243 	}
244 
245 	/*
246 	 * Initialize the table entry. Set the pointer to NULL, since the
247 	 * table is not fully mapped at this time.
248 	 */
249 	table_desc = &acpi_gbl_root_table_list.tables[table_index];
250 
251 	table_desc->address = address;
252 	table_desc->pointer = NULL;
253 	table_desc->length = table->length;
254 	table_desc->flags = ACPI_TABLE_ORIGIN_MAPPED;
255 	ACPI_MOVE_32_TO_32(table_desc->signature.ascii, table->signature);
256 
257 	/*
258 	 * ACPI Table Override:
259 	 *
260 	 * Before we install the table, let the host OS override it with a new
261 	 * one if desired. Any table within the RSDT/XSDT can be replaced,
262 	 * including the DSDT which is pointed to by the FADT.
263 	 *
264 	 * NOTE: If the table is overridden, then final_table will contain a
265 	 * mapped pointer to the full new table. If the table is not overridden,
266 	 * or if there has been a physical override, then the table will be
267 	 * fully mapped later (in verify table). In any case, we must
268 	 * unmap the header that was mapped above.
269 	 */
270 	final_table = acpi_tb_table_override(table, table_desc);
271 	if (!final_table) {
272 		final_table = table;	/* There was no override */
273 	}
274 
275 	acpi_tb_print_table_header(table_desc->address, final_table);
276 
277 	/* Set the global integer width (based upon revision of the DSDT) */
278 
279 	if (table_index == ACPI_TABLE_INDEX_DSDT) {
280 		acpi_ut_set_integer_width(final_table->revision);
281 	}
282 
283 	/*
284 	 * If we have a physical override during this early loading of the ACPI
285 	 * tables, unmap the table for now. It will be mapped again later when
286 	 * it is actually used. This supports very early loading of ACPI tables,
287 	 * before virtual memory is fully initialized and running within the
288 	 * host OS. Note: A logical override has the ACPI_TABLE_ORIGIN_OVERRIDE
289 	 * flag set and will not be deleted below.
290 	 */
291 	if (final_table != table) {
292 		acpi_tb_delete_table(table_desc);
293 	}
294 
295 unmap_and_exit:
296 
297 	/* Always unmap the table header that we mapped above */
298 
299 	acpi_os_unmap_memory(table, sizeof(struct acpi_table_header));
300 }
301 
302 /*******************************************************************************
303  *
304  * FUNCTION:    acpi_tb_get_root_table_entry
305  *
306  * PARAMETERS:  table_entry         - Pointer to the RSDT/XSDT table entry
307  *              table_entry_size    - sizeof 32 or 64 (RSDT or XSDT)
308  *
309  * RETURN:      Physical address extracted from the root table
310  *
311  * DESCRIPTION: Get one root table entry. Handles 32-bit and 64-bit cases on
312  *              both 32-bit and 64-bit platforms
313  *
314  * NOTE:        acpi_physical_address is 32-bit on 32-bit platforms, 64-bit on
315  *              64-bit platforms.
316  *
317  ******************************************************************************/
318 
319 static acpi_physical_address
320 acpi_tb_get_root_table_entry(u8 *table_entry, u32 table_entry_size)
321 {
322 	u64 address64;
323 
324 	/*
325 	 * Get the table physical address (32-bit for RSDT, 64-bit for XSDT):
326 	 * Note: Addresses are 32-bit aligned (not 64) in both RSDT and XSDT
327 	 */
328 	if (table_entry_size == ACPI_RSDT_ENTRY_SIZE) {
329 		/*
330 		 * 32-bit platform, RSDT: Return 32-bit table entry
331 		 * 64-bit platform, RSDT: Expand 32-bit to 64-bit and return
332 		 */
333 		return ((acpi_physical_address)
334 			(*ACPI_CAST_PTR(u32, table_entry)));
335 	} else {
336 		/*
337 		 * 32-bit platform, XSDT: Truncate 64-bit to 32-bit and return
338 		 * 64-bit platform, XSDT: Move (unaligned) 64-bit to local,
339 		 *  return 64-bit
340 		 */
341 		ACPI_MOVE_64_TO_64(&address64, table_entry);
342 
343 #if ACPI_MACHINE_WIDTH == 32
344 		if (address64 > ACPI_UINT32_MAX) {
345 
346 			/* Will truncate 64-bit address to 32 bits, issue warning */
347 
348 			ACPI_BIOS_WARNING((AE_INFO,
349 					   "64-bit Physical Address in XSDT is too large (0x%8.8X%8.8X),"
350 					   " truncating",
351 					   ACPI_FORMAT_UINT64(address64)));
352 		}
353 #endif
354 		return ((acpi_physical_address) (address64));
355 	}
356 }
357 
358 /*******************************************************************************
359  *
360  * FUNCTION:    acpi_tb_validate_xsdt
361  *
362  * PARAMETERS:  address             - Physical address of the XSDT (from RSDP)
363  *
364  * RETURN:      Status. AE_OK if the table appears to be valid.
365  *
366  * DESCRIPTION: Validate an XSDT to ensure that it is of minimum size and does
367  *              not contain any NULL entries. A problem that is seen in the
368  *              field is that the XSDT exists, but is actually useless because
369  *              of one or more (or all) NULL entries.
370  *
371  ******************************************************************************/
372 
373 static acpi_status acpi_tb_validate_xsdt(acpi_physical_address xsdt_address)
374 {
375 	struct acpi_table_header *table;
376 	u8 *next_entry;
377 	acpi_physical_address address;
378 	u32 length;
379 	u32 entry_count;
380 	acpi_status status;
381 	u32 i;
382 
383 	/* Get the XSDT length */
384 
385 	table =
386 	    acpi_os_map_memory(xsdt_address, sizeof(struct acpi_table_header));
387 	if (!table) {
388 		return (AE_NO_MEMORY);
389 	}
390 
391 	length = table->length;
392 	acpi_os_unmap_memory(table, sizeof(struct acpi_table_header));
393 
394 	/*
395 	 * Minimum XSDT length is the size of the standard ACPI header
396 	 * plus one physical address entry
397 	 */
398 	if (length < (sizeof(struct acpi_table_header) + ACPI_XSDT_ENTRY_SIZE)) {
399 		return (AE_INVALID_TABLE_LENGTH);
400 	}
401 
402 	/* Map the entire XSDT */
403 
404 	table = acpi_os_map_memory(xsdt_address, length);
405 	if (!table) {
406 		return (AE_NO_MEMORY);
407 	}
408 
409 	/* Get the number of entries and pointer to first entry */
410 
411 	status = AE_OK;
412 	next_entry = ACPI_ADD_PTR(u8, table, sizeof(struct acpi_table_header));
413 	entry_count = (u32)((table->length - sizeof(struct acpi_table_header)) /
414 			    ACPI_XSDT_ENTRY_SIZE);
415 
416 	/* Validate each entry (physical address) within the XSDT */
417 
418 	for (i = 0; i < entry_count; i++) {
419 		address =
420 		    acpi_tb_get_root_table_entry(next_entry,
421 						 ACPI_XSDT_ENTRY_SIZE);
422 		if (!address) {
423 
424 			/* Detected a NULL entry, XSDT is invalid */
425 
426 			status = AE_NULL_ENTRY;
427 			break;
428 		}
429 
430 		next_entry += ACPI_XSDT_ENTRY_SIZE;
431 	}
432 
433 	/* Unmap table */
434 
435 	acpi_os_unmap_memory(table, length);
436 	return (status);
437 }
438 
439 /*******************************************************************************
440  *
441  * FUNCTION:    acpi_tb_parse_root_table
442  *
443  * PARAMETERS:  rsdp                    - Pointer to the RSDP
444  *
445  * RETURN:      Status
446  *
447  * DESCRIPTION: This function is called to parse the Root System Description
448  *              Table (RSDT or XSDT)
449  *
450  * NOTE:        Tables are mapped (not copied) for efficiency. The FACS must
451  *              be mapped and cannot be copied because it contains the actual
452  *              memory location of the ACPI Global Lock.
453  *
454  ******************************************************************************/
455 
456 acpi_status __init acpi_tb_parse_root_table(acpi_physical_address rsdp_address)
457 {
458 	struct acpi_table_rsdp *rsdp;
459 	u32 table_entry_size;
460 	u32 i;
461 	u32 table_count;
462 	struct acpi_table_header *table;
463 	acpi_physical_address address;
464 	u32 length;
465 	u8 *table_entry;
466 	acpi_status status;
467 
468 	ACPI_FUNCTION_TRACE(tb_parse_root_table);
469 
470 	/* Map the entire RSDP and extract the address of the RSDT or XSDT */
471 
472 	rsdp = acpi_os_map_memory(rsdp_address, sizeof(struct acpi_table_rsdp));
473 	if (!rsdp) {
474 		return_ACPI_STATUS(AE_NO_MEMORY);
475 	}
476 
477 	acpi_tb_print_table_header(rsdp_address,
478 				   ACPI_CAST_PTR(struct acpi_table_header,
479 						 rsdp));
480 
481 	/* Use XSDT if present and not overridden. Otherwise, use RSDT */
482 
483 	if ((rsdp->revision > 1) &&
484 	    rsdp->xsdt_physical_address && !acpi_gbl_do_not_use_xsdt) {
485 		/*
486 		 * RSDP contains an XSDT (64-bit physical addresses). We must use
487 		 * the XSDT if the revision is > 1 and the XSDT pointer is present,
488 		 * as per the ACPI specification.
489 		 */
490 		address = (acpi_physical_address) rsdp->xsdt_physical_address;
491 		table_entry_size = ACPI_XSDT_ENTRY_SIZE;
492 	} else {
493 		/* Root table is an RSDT (32-bit physical addresses) */
494 
495 		address = (acpi_physical_address) rsdp->rsdt_physical_address;
496 		table_entry_size = ACPI_RSDT_ENTRY_SIZE;
497 	}
498 
499 	/*
500 	 * It is not possible to map more than one entry in some environments,
501 	 * so unmap the RSDP here before mapping other tables
502 	 */
503 	acpi_os_unmap_memory(rsdp, sizeof(struct acpi_table_rsdp));
504 
505 	/*
506 	 * If it is present and used, validate the XSDT for access/size
507 	 * and ensure that all table entries are at least non-NULL
508 	 */
509 	if (table_entry_size == ACPI_XSDT_ENTRY_SIZE) {
510 		status = acpi_tb_validate_xsdt(address);
511 		if (ACPI_FAILURE(status)) {
512 			ACPI_BIOS_WARNING((AE_INFO,
513 					   "XSDT is invalid (%s), using RSDT",
514 					   acpi_format_exception(status)));
515 
516 			/* Fall back to the RSDT */
517 
518 			address =
519 			    (acpi_physical_address) rsdp->rsdt_physical_address;
520 			table_entry_size = ACPI_RSDT_ENTRY_SIZE;
521 		}
522 	}
523 
524 	/* Map the RSDT/XSDT table header to get the full table length */
525 
526 	table = acpi_os_map_memory(address, sizeof(struct acpi_table_header));
527 	if (!table) {
528 		return_ACPI_STATUS(AE_NO_MEMORY);
529 	}
530 
531 	acpi_tb_print_table_header(address, table);
532 
533 	/*
534 	 * Validate length of the table, and map entire table.
535 	 * Minimum length table must contain at least one entry.
536 	 */
537 	length = table->length;
538 	acpi_os_unmap_memory(table, sizeof(struct acpi_table_header));
539 
540 	if (length < (sizeof(struct acpi_table_header) + table_entry_size)) {
541 		ACPI_BIOS_ERROR((AE_INFO,
542 				 "Invalid table length 0x%X in RSDT/XSDT",
543 				 length));
544 		return_ACPI_STATUS(AE_INVALID_TABLE_LENGTH);
545 	}
546 
547 	table = acpi_os_map_memory(address, length);
548 	if (!table) {
549 		return_ACPI_STATUS(AE_NO_MEMORY);
550 	}
551 
552 	/* Validate the root table checksum */
553 
554 	status = acpi_tb_verify_checksum(table, length);
555 	if (ACPI_FAILURE(status)) {
556 		acpi_os_unmap_memory(table, length);
557 		return_ACPI_STATUS(status);
558 	}
559 
560 	/* Get the number of entries and pointer to first entry */
561 
562 	table_count = (u32)((table->length - sizeof(struct acpi_table_header)) /
563 			    table_entry_size);
564 	table_entry = ACPI_ADD_PTR(u8, table, sizeof(struct acpi_table_header));
565 
566 	/*
567 	 * First two entries in the table array are reserved for the DSDT
568 	 * and FACS, which are not actually present in the RSDT/XSDT - they
569 	 * come from the FADT
570 	 */
571 	acpi_gbl_root_table_list.current_table_count = 2;
572 
573 	/* Initialize the root table array from the RSDT/XSDT */
574 
575 	for (i = 0; i < table_count; i++) {
576 		if (acpi_gbl_root_table_list.current_table_count >=
577 		    acpi_gbl_root_table_list.max_table_count) {
578 
579 			/* There is no more room in the root table array, attempt resize */
580 
581 			status = acpi_tb_resize_root_table_list();
582 			if (ACPI_FAILURE(status)) {
583 				ACPI_WARNING((AE_INFO,
584 					      "Truncating %u table entries!",
585 					      (unsigned) (table_count -
586 					       (acpi_gbl_root_table_list.
587 							  current_table_count -
588 							  2))));
589 				break;
590 			}
591 		}
592 
593 		/* Get the table physical address (32-bit for RSDT, 64-bit for XSDT) */
594 
595 		acpi_gbl_root_table_list.tables[acpi_gbl_root_table_list.
596 						current_table_count].address =
597 		    acpi_tb_get_root_table_entry(table_entry, table_entry_size);
598 
599 		table_entry += table_entry_size;
600 		acpi_gbl_root_table_list.current_table_count++;
601 	}
602 
603 	/*
604 	 * It is not possible to map more than one entry in some environments,
605 	 * so unmap the root table here before mapping other tables
606 	 */
607 	acpi_os_unmap_memory(table, length);
608 
609 	/*
610 	 * Complete the initialization of the root table array by examining
611 	 * the header of each table
612 	 */
613 	for (i = 2; i < acpi_gbl_root_table_list.current_table_count; i++) {
614 		acpi_tb_install_table(acpi_gbl_root_table_list.tables[i].
615 				      address, NULL, i);
616 
617 		/* Special case for FADT - validate it then get the DSDT and FACS */
618 
619 		if (ACPI_COMPARE_NAME
620 		    (&acpi_gbl_root_table_list.tables[i].signature,
621 		     ACPI_SIG_FADT)) {
622 			acpi_tb_parse_fadt(i);
623 		}
624 	}
625 
626 	return_ACPI_STATUS(AE_OK);
627 }
628