summaryrefslogtreecommitdiffstats
path: root/drivers/acpi/acpica/tbfadt.c
blob: 1e1a7de34439678fbb8f7cad23335f43f6bab907 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
/******************************************************************************
 *
 * Module Name: tbfadt   - FADT table utilities
 *
 *****************************************************************************/

/*
 * Copyright (C) 2000 - 2011, Intel Corp.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions, and the following disclaimer,
 *    without modification.
 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
 *    substantially similar to the "NO WARRANTY" disclaimer below
 *    ("Disclaimer") and any redistribution must be conditioned upon
 *    including a substantially similar Disclaimer requirement for further
 *    binary redistribution.
 * 3. Neither the names of the above-listed copyright holders nor the names
 *    of any contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * Alternatively, this software may be distributed under the terms of the
 * GNU General Public License ("GPL") version 2 as published by the Free
 * Software Foundation.
 *
 * NO WARRANTY
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGES.
 */

#include <acpi/acpi.h>
#include "accommon.h"
#include "actables.h"

#define _COMPONENT          ACPI_TABLES
ACPI_MODULE_NAME("tbfadt")

/* Local prototypes */
static ACPI_INLINE void
acpi_tb_init_generic_address(struct acpi_generic_address *generic_address,
			     u8 space_id, u8 byte_width, u64 address);

static void acpi_tb_convert_fadt(void);

static void acpi_tb_validate_fadt(void);

static void acpi_tb_setup_fadt_registers(void);

/* Table for conversion of FADT to common internal format and FADT validation */

typedef struct acpi_fadt_info {
	char *name;
	u8 address64;
	u8 address32;
	u8 length;
	u8 default_length;
	u8 type;

} acpi_fadt_info;

#define ACPI_FADT_REQUIRED          1
#define ACPI_FADT_SEPARATE_LENGTH   2

static struct acpi_fadt_info fadt_info_table[] = {
	{"Pm1aEventBlock",
	 ACPI_FADT_OFFSET(xpm1a_event_block),
	 ACPI_FADT_OFFSET(pm1a_event_block),
	 ACPI_FADT_OFFSET(pm1_event_length),
	 ACPI_PM1_REGISTER_WIDTH * 2,	/* Enable + Status register */
	 ACPI_FADT_REQUIRED},

	{"Pm1bEventBlock",
	 ACPI_FADT_OFFSET(xpm1b_event_block),
	 ACPI_FADT_OFFSET(pm1b_event_block),
	 ACPI_FADT_OFFSET(pm1_event_length),
	 ACPI_PM1_REGISTER_WIDTH * 2,	/* Enable + Status register */
	 0},

	{"Pm1aControlBlock",
	 ACPI_FADT_OFFSET(xpm1a_control_block),
	 ACPI_FADT_OFFSET(pm1a_control_block),
	 ACPI_FADT_OFFSET(pm1_control_length),
	 ACPI_PM1_REGISTER_WIDTH,
	 ACPI_FADT_REQUIRED},

	{"Pm1bControlBlock",
	 ACPI_FADT_OFFSET(xpm1b_control_block),
	 ACPI_FADT_OFFSET(pm1b_control_block),
	 ACPI_FADT_OFFSET(pm1_control_length),
	 ACPI_PM1_REGISTER_WIDTH,
	 0},

	{"Pm2ControlBlock",
	 ACPI_FADT_OFFSET(xpm2_control_block),
	 ACPI_FADT_OFFSET(pm2_control_block),
	 ACPI_FADT_OFFSET(pm2_control_length),
	 ACPI_PM2_REGISTER_WIDTH,
	 ACPI_FADT_SEPARATE_LENGTH},

	{"PmTimerBlock",
	 ACPI_FADT_OFFSET(xpm_timer_block),
	 ACPI_FADT_OFFSET(pm_timer_block),
	 ACPI_FADT_OFFSET(pm_timer_length),
	 ACPI_PM_TIMER_WIDTH,
	 ACPI_FADT_REQUIRED},

	{"Gpe0Block",
	 ACPI_FADT_OFFSET(xgpe0_block),
	 ACPI_FADT_OFFSET(gpe0_block),
	 ACPI_FADT_OFFSET(gpe0_block_length),
	 0,
	 ACPI_FADT_SEPARATE_LENGTH},

	{"Gpe1Block",
	 ACPI_FADT_OFFSET(xgpe1_block),
	 ACPI_FADT_OFFSET(gpe1_block),
	 ACPI_FADT_OFFSET(gpe1_block_length),
	 0,
	 ACPI_FADT_SEPARATE_LENGTH}
};

#define ACPI_FADT_INFO_ENTRIES \
			(sizeof (fadt_info_table) / sizeof (struct acpi_fadt_info))

/* Table used to split Event Blocks into separate status/enable registers */

typedef struct acpi_fadt_pm_info {
	struct acpi_generic_address *target;
	u8 source;
	u8 register_num;

} acpi_fadt_pm_info;

static struct acpi_fadt_pm_info fadt_pm_info_table[] = {
	{&acpi_gbl_xpm1a_status,
	 ACPI_FADT_OFFSET(xpm1a_event_block),
	 0},

	{&acpi_gbl_xpm1a_enable,
	 ACPI_FADT_OFFSET(xpm1a_event_block),
	 1},

	{&acpi_gbl_xpm1b_status,
	 ACPI_FADT_OFFSET(xpm1b_event_block),
	 0},

	{&acpi_gbl_xpm1b_enable,
	 ACPI_FADT_OFFSET(xpm1b_event_block),
	 1}
};

#define ACPI_FADT_PM_INFO_ENTRIES \
			(sizeof (fadt_pm_info_table) / sizeof (struct acpi_fadt_pm_info))

/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_init_generic_address
 *
 * PARAMETERS:  generic_address     - GAS struct to be initialized
 *              byte_width          - Width of this register
 *              Address             - Address of the register
 *
 * RETURN:      None
 *
 * DESCRIPTION: Initialize a Generic Address Structure (GAS)
 *              See the ACPI specification for a full description and
 *              definition of this structure.
 *
 ******************************************************************************/

static ACPI_INLINE void
acpi_tb_init_generic_address(struct acpi_generic_address *generic_address,
			     u8 space_id, u8 byte_width, u64 address)
{

	/*
	 * The 64-bit Address field is non-aligned in the byte packed
	 * GAS struct.
	 */
	ACPI_MOVE_64_TO_64(&generic_address->address, &address);

	/* All other fields are byte-wide */

	generic_address->space_id = space_id;
	generic_address->bit_width = (u8)ACPI_MUL_8(byte_width);
	generic_address->bit_offset = 0;
	generic_address->access_width = 0;	/* Access width ANY */
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_parse_fadt
 *
 * PARAMETERS:  table_index         - Index for the FADT
 *
 * RETURN:      None
 *
 * DESCRIPTION: Initialize the FADT, DSDT and FACS tables
 *              (FADT contains the addresses of the DSDT and FACS)
 *
 ******************************************************************************/

void acpi_tb_parse_fadt(u32 table_index)
{
	u32 length;
	struct acpi_table_header *table;

	/*
	 * The FADT has multiple versions with different lengths,
	 * and it contains pointers to both the DSDT and FACS tables.
	 *
	 * Get a local copy of the FADT and convert it to a common format
	 * Map entire FADT, assumed to be smaller than one page.
	 */
	length = acpi_gbl_root_table_list.tables[table_index].length;

	table =
	    acpi_os_map_memory(acpi_gbl_root_table_list.tables[table_index].
			       address, length);
	if (!table) {
		return;
	}

	/*
	 * Validate the FADT checksum before we copy the table. Ignore
	 * checksum error as we want to try to get the DSDT and FACS.
	 */
	(void)acpi_tb_verify_checksum(table, length);

	/* Create a local copy of the FADT in common ACPI 2.0+ format */

	acpi_tb_create_local_fadt(table, length);

	/* All done with the real FADT, unmap it */

	acpi_os_unmap_memory(table, length);

	/* Obtain the DSDT and FACS tables via their addresses within the FADT */

	acpi_tb_install_table((acpi_physical_address) acpi_gbl_FADT.Xdsdt,
			      ACPI_SIG_DSDT, ACPI_TABLE_INDEX_DSDT);

	/* If Hardware Reduced flag is set, there is no FACS */

	if (!acpi_gbl_reduced_hardware) {
		acpi_tb_install_table((acpi_physical_address) acpi_gbl_FADT.
				      Xfacs, ACPI_SIG_FACS,
				      ACPI_TABLE_INDEX_FACS);
	}
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_create_local_fadt
 *
 * PARAMETERS:  Table               - Pointer to BIOS FADT
 *              Length              - Length of the table
 *
 * RETURN:      None
 *
 * DESCRIPTION: Get a local copy of the FADT and convert it to a common format.
 *              Performs validation on some important FADT fields.
 *
 * NOTE:        We create a local copy of the FADT regardless of the version.
 *
 ******************************************************************************/

void acpi_tb_create_local_fadt(struct acpi_table_header *table, u32 length)
{
	/*
	 * Check if the FADT is larger than the largest table that we expect
	 * (the ACPI 5.0 version). If so, truncate the table, and issue
	 * a warning.
	 */
	if (length > sizeof(struct acpi_table_fadt)) {
		ACPI_WARNING((AE_INFO,
			      "FADT (revision %u) is longer than ACPI 5.0 version, "
			      "truncating length %u to %u",
			      table->revision, length,
			      (u32)sizeof(struct acpi_table_fadt)));
	}

	/* Clear the entire local FADT */

	ACPI_MEMSET(&acpi_gbl_FADT, 0, sizeof(struct acpi_table_fadt));

	/* Copy the original FADT, up to sizeof (struct acpi_table_fadt) */

	ACPI_MEMCPY(&acpi_gbl_FADT, table,
		    ACPI_MIN(length, sizeof(struct acpi_table_fadt)));

	/* Take a copy of the Hardware Reduced flag */

	acpi_gbl_reduced_hardware = FALSE;
	if (acpi_gbl_FADT.flags & ACPI_FADT_HW_REDUCED) {
		acpi_gbl_reduced_hardware = TRUE;
	}

	/* Convert the local copy of the FADT to the common internal format */

	acpi_tb_convert_fadt();

	/* Validate FADT values now, before we make any changes */

	acpi_tb_validate_fadt();

	/* Initialize the global ACPI register structures */

	acpi_tb_setup_fadt_registers();
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_convert_fadt
 *
 * PARAMETERS:  None, uses acpi_gbl_FADT
 *
 * RETURN:      None
 *
 * DESCRIPTION: Converts all versions of the FADT to a common internal format.
 *              Expand 32-bit addresses to 64-bit as necessary.
 *
 * NOTE:        acpi_gbl_FADT must be of size (struct acpi_table_fadt),
 *              and must contain a copy of the actual FADT.
 *
 * Notes on 64-bit register addresses:
 *
 * After this FADT conversion, later ACPICA code will only use the 64-bit "X"
 * fields of the FADT for all ACPI register addresses.
 *
 * The 64-bit "X" fields are optional extensions to the original 32-bit FADT
 * V1.0 fields. Even if they are present in the FADT, they are optional and
 * are unused if the BIOS sets them to zero. Therefore, we must copy/expand
 * 32-bit V1.0 fields if the corresponding X field is zero.
 *
 * For ACPI 1.0 FADTs, all 32-bit address fields are expanded to the
 * corresponding "X" fields in the internal FADT.
 *
 * For ACPI 2.0+ FADTs, all valid (non-zero) 32-bit address fields are expanded
 * to the corresponding 64-bit X fields. For compatibility with other ACPI
 * implementations, we ignore the 64-bit field if the 32-bit field is valid,
 * regardless of whether the host OS is 32-bit or 64-bit.
 *
 ******************************************************************************/

static void acpi_tb_convert_fadt(void)
{
	struct acpi_generic_address *address64;
	u32 address32;
	u32 i;

	/* Update the local FADT table header length */

	acpi_gbl_FADT.header.length = sizeof(struct acpi_table_fadt);

	/*
	 * Expand the 32-bit FACS and DSDT addresses to 64-bit as necessary.
	 * Later code will always use the X 64-bit field. Also, check for an
	 * address mismatch between the 32-bit and 64-bit address fields
	 * (FIRMWARE_CTRL/X_FIRMWARE_CTRL, DSDT/X_DSDT) which would indicate
	 * the presence of two FACS or two DSDT tables.
	 */
	if (!acpi_gbl_FADT.Xfacs) {
		acpi_gbl_FADT.Xfacs = (u64) acpi_gbl_FADT.facs;
	} else if (acpi_gbl_FADT.facs &&
		   (acpi_gbl_FADT.Xfacs != (u64) acpi_gbl_FADT.facs)) {
		ACPI_WARNING((AE_INFO,
		    "32/64 FACS address mismatch in FADT - two FACS tables!"));
	}

	if (!acpi_gbl_FADT.Xdsdt) {
		acpi_gbl_FADT.Xdsdt = (u64) acpi_gbl_FADT.dsdt;
	} else if (acpi_gbl_FADT.dsdt &&
		   (acpi_gbl_FADT.Xdsdt != (u64) acpi_gbl_FADT.dsdt)) {
		ACPI_WARNING((AE_INFO,
		    "32/64 DSDT address mismatch in FADT - two DSDT tables!"));
	}

	/*
	 * For ACPI 1.0 FADTs (revision 1 or 2), ensure that reserved fields which
	 * should be zero are indeed zero. This will workaround BIOSs that
	 * inadvertently place values in these fields.
	 *
	 * The ACPI 1.0 reserved fields that will be zeroed are the bytes located at
	 * offset 45, 55, 95, and the word located at offset 109, 110.
	 *
	 * Note: The FADT revision value is unreliable. Only the length can be
	 * trusted.
	 */
	if (acpi_gbl_FADT.header.length <= ACPI_FADT_V2_SIZE) {
		acpi_gbl_FADT.preferred_profile = 0;
		acpi_gbl_FADT.pstate_control = 0;
		acpi_gbl_FADT.cst_control = 0;
		acpi_gbl_FADT.boot_flags = 0;
	}

	/*
	 * Expand the ACPI 1.0 32-bit addresses to the ACPI 2.0 64-bit "X"
	 * generic address structures as necessary. Later code will always use
	 * the 64-bit address structures.
	 *
	 * March 2009:
	 * We now always use the 32-bit address if it is valid (non-null). This
	 * is not in accordance with the ACPI specification which states that
	 * the 64-bit address supersedes the 32-bit version, but we do this for
	 * compatibility with other ACPI implementations. Most notably, in the
	 * case where both the 32 and 64 versions are non-null, we use the 32-bit
	 * version. This is the only address that is guaranteed to have been
	 * tested by the BIOS manufacturer.
	 */
	for (i = 0; i < ACPI_FADT_INFO_ENTRIES; i++) {
		address32 = *ACPI_ADD_PTR(u32,
					  &acpi_gbl_FADT,
					  fadt_info_table[i].address32);

		address64 = ACPI_ADD_PTR(struct acpi_generic_address,
					 &acpi_gbl_FADT,
					 fadt_info_table[i].address64);

		/*
		 * If both 32- and 64-bit addresses are valid (non-zero),
		 * they must match.
		 */
		if (address64->address && address32 &&
		    (address64->address != (u64) address32)) {
			ACPI_ERROR((AE_INFO,
				    "32/64X address mismatch in %s: 0x%8.8X/0x%8.8X%8.8X, using 32",
				    fadt_info_table[i].name, address32,
				    ACPI_FORMAT_UINT64(address64->address)));
		}

		/* Always use 32-bit address if it is valid (non-null) */

		if (address32) {
			/*
			 * Copy the 32-bit address to the 64-bit GAS structure. The
			 * Space ID is always I/O for 32-bit legacy address fields
			*/
			acpi_tb_init_generic_address(address64,
						     ACPI_ADR_SPACE_SYSTEM_IO,
						     *ACPI_ADD_PTR(u8,
								   &acpi_gbl_FADT,
								   fadt_info_table
								   [i].length),
						     (u64) address32);
		}
	}
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_validate_fadt
 *
 * PARAMETERS:  Table           - Pointer to the FADT to be validated
 *
 * RETURN:      None
 *
 * DESCRIPTION: Validate various important fields within the FADT. If a problem
 *              is found, issue a message, but no status is returned.
 *              Used by both the table manager and the disassembler.
 *
 * Possible additional checks:
 * (acpi_gbl_FADT.pm1_event_length >= 4)
 * (acpi_gbl_FADT.pm1_control_length >= 2)
 * (acpi_gbl_FADT.pm_timer_length >= 4)
 * Gpe block lengths must be multiple of 2
 *
 ******************************************************************************/

static void acpi_tb_validate_fadt(void)
{
	char *name;
	struct acpi_generic_address *address64;
	u8 length;
	u32 i;

	/*
	 * Check for FACS and DSDT address mismatches. An address mismatch between
	 * the 32-bit and 64-bit address fields (FIRMWARE_CTRL/X_FIRMWARE_CTRL and
	 * DSDT/X_DSDT) would indicate the presence of two FACS or two DSDT tables.
	 */
	if (acpi_gbl_FADT.facs &&
	    (acpi_gbl_FADT.Xfacs != (u64) acpi_gbl_FADT.facs)) {
		ACPI_WARNING((AE_INFO,
			      "32/64X FACS address mismatch in FADT - "
			      "0x%8.8X/0x%8.8X%8.8X, using 32",
			      acpi_gbl_FADT.facs,
			      ACPI_FORMAT_UINT64(acpi_gbl_FADT.Xfacs)));

		acpi_gbl_FADT.Xfacs = (u64) acpi_gbl_FADT.facs;
	}

	if (acpi_gbl_FADT.dsdt &&
	    (acpi_gbl_FADT.Xdsdt != (u64) acpi_gbl_FADT.dsdt)) {
		ACPI_WARNING((AE_INFO,
			      "32/64X DSDT address mismatch in FADT - "
			      "0x%8.8X/0x%8.8X%8.8X, using 32",
			      acpi_gbl_FADT.dsdt,
			      ACPI_FORMAT_UINT64(acpi_gbl_FADT.Xdsdt)));

		acpi_gbl_FADT.Xdsdt = (u64) acpi_gbl_FADT.dsdt;
	}

	/* If Hardware Reduced flag is set, we are all done */

	if (acpi_gbl_reduced_hardware) {
		return;
	}

	/* Examine all of the 64-bit extended address fields (X fields) */

	for (i = 0; i < ACPI_FADT_INFO_ENTRIES; i++) {
		/*
		 * Generate pointer to the 64-bit address, get the register
		 * length (width) and the register name
		 */
		address64 = ACPI_ADD_PTR(struct acpi_generic_address,
					 &acpi_gbl_FADT,
					 fadt_info_table[i].address64);
		length =
		    *ACPI_ADD_PTR(u8, &acpi_gbl_FADT,
				  fadt_info_table[i].length);
		name = fadt_info_table[i].name;

		/*
		 * For each extended field, check for length mismatch between the
		 * legacy length field and the corresponding 64-bit X length field.
		 */
		if (address64->address &&
		    (address64->bit_width != ACPI_MUL_8(length))) {
			ACPI_WARNING((AE_INFO,
				      "32/64X length mismatch in %s: %u/%u",
				      name, ACPI_MUL_8(length),
				      address64->bit_width));
		}

		if (fadt_info_table[i].type & ACPI_FADT_REQUIRED) {
			/*
			 * Field is required (Pm1a_event, Pm1a_control, pm_timer).
			 * Both the address and length must be non-zero.
			 */
			if (!address64->address || !length) {
				ACPI_ERROR((AE_INFO,
					    "Required field %s has zero address and/or length:"
					    " 0x%8.8X%8.8X/0x%X",
					    name,
					    ACPI_FORMAT_UINT64(address64->
							       address),
					    length));
			}
		} else if (fadt_info_table[i].type & ACPI_FADT_SEPARATE_LENGTH) {
			/*
			 * Field is optional (PM2Control, GPE0, GPE1) AND has its own
			 * length field. If present, both the address and length must
			 * be valid.
			 */
			if ((address64->address && !length) ||
			    (!address64->address && length)) {
				ACPI_WARNING((AE_INFO,
					      "Optional field %s has zero address or length: "
					      "0x%8.8X%8.8X/0x%X",
					      name,
					      ACPI_FORMAT_UINT64(address64->
								 address),
					      length));
			}
		}
	}
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_setup_fadt_registers
 *
 * PARAMETERS:  None, uses acpi_gbl_FADT.
 *
 * RETURN:      None
 *
 * DESCRIPTION: Initialize global ACPI PM1 register definitions. Optionally,
 *              force FADT register definitions to their default lengths.
 *
 ******************************************************************************/

static void acpi_tb_setup_fadt_registers(void)
{
	struct acpi_generic_address *target64;
	struct acpi_generic_address *source64;
	u8 pm1_register_byte_width;
	u32 i;

	/*
	 * Optionally check all register lengths against the default values and
	 * update them if they are incorrect.
	 */
	if (acpi_gbl_use_default_register_widths) {
		for (i = 0; i < ACPI_FADT_INFO_ENTRIES; i++) {
			target64 =
			    ACPI_ADD_PTR(struct acpi_generic_address,
					 &acpi_gbl_FADT,
					 fadt_info_table[i].address64);

			/*
			 * If a valid register (Address != 0) and the (default_length > 0)
			 * (Not a GPE register), then check the width against the default.
			 */
			if ((target64->address) &&
			    (fadt_info_table[i].default_length > 0) &&
			    (fadt_info_table[i].default_length !=
			     target64->bit_width)) {
				ACPI_WARNING((AE_INFO,
					      "Invalid length for %s: %u, using default %u",
					      fadt_info_table[i].name,
					      target64->bit_width,
					      fadt_info_table[i].
					      default_length));

				/* Incorrect size, set width to the default */

				target64->bit_width =
				    fadt_info_table[i].default_length;
			}
		}
	}

	/*
	 * Get the length of the individual PM1 registers (enable and status).
	 * Each register is defined to be (event block length / 2). Extra divide
	 * by 8 converts bits to bytes.
	 */
	pm1_register_byte_width = (u8)
	    ACPI_DIV_16(acpi_gbl_FADT.xpm1a_event_block.bit_width);

	/*
	 * Calculate separate GAS structs for the PM1x (A/B) Status and Enable
	 * registers. These addresses do not appear (directly) in the FADT, so it
	 * is useful to pre-calculate them from the PM1 Event Block definitions.
	 *
	 * The PM event blocks are split into two register blocks, first is the
	 * PM Status Register block, followed immediately by the PM Enable
	 * Register block. Each is of length (pm1_event_length/2)
	 *
	 * Note: The PM1A event block is required by the ACPI specification.
	 * However, the PM1B event block is optional and is rarely, if ever,
	 * used.
	 */

	for (i = 0; i < ACPI_FADT_PM_INFO_ENTRIES; i++) {
		source64 =
		    ACPI_ADD_PTR(struct acpi_generic_address, &acpi_gbl_FADT,
				 fadt_pm_info_table[i].source);

		if (source64->address) {
			acpi_tb_init_generic_address(fadt_pm_info_table[i].
						     target, source64->space_id,
						     pm1_register_byte_width,
						     source64->address +
						     (fadt_pm_info_table[i].
						      register_num *
						      pm1_register_byte_width));
		}
	}
}