tbfadt.c 19.5 KB
Newer Older
1 2 3 4 5 6 7
/******************************************************************************
 *
 * Module Name: tbfadt   - FADT table utilities
 *
 *****************************************************************************/

/*
L
Len Brown 已提交
8
 * Copyright (C) 2000 - 2008, Intel Corp.
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
 * 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>
L
Len Brown 已提交
45 46
#include "accommon.h"
#include "actables.h"
47 48 49 50 51

#define _COMPONENT          ACPI_TABLES
ACPI_MODULE_NAME("tbfadt")

/* Local prototypes */
52
static inline void
53
acpi_tb_init_generic_address(struct acpi_generic_address *generic_address,
B
Bob Moore 已提交
54
			     u8 space_id, u8 byte_width, u64 address);
55

56 57 58 59
static void acpi_tb_convert_fadt(void);

static void acpi_tb_validate_fadt(void);

60 61
static void acpi_tb_setup_fadt_registers(void);

62
/* Table for conversion of FADT to common internal format and FADT validation */
63

64 65
typedef struct acpi_fadt_info {
	char *name;
66 67
	u8 address64;
	u8 address32;
68
	u8 length;
69
	u8 default_length;
70
	u8 type;
71

72
} acpi_fadt_info;
73

74 75 76 77
#define ACPI_FADT_REQUIRED          1
#define ACPI_FADT_SEPARATE_LENGTH   2

static struct acpi_fadt_info fadt_info_table[] = {
78 79
	{"Pm1aEventBlock",
	 ACPI_FADT_OFFSET(xpm1a_event_block),
80
	 ACPI_FADT_OFFSET(pm1a_event_block),
81 82 83
	 ACPI_FADT_OFFSET(pm1_event_length),
	 ACPI_PM1_REGISTER_WIDTH * 2,	/* Enable + Status register */
	 ACPI_FADT_REQUIRED},
84

85 86
	{"Pm1bEventBlock",
	 ACPI_FADT_OFFSET(xpm1b_event_block),
87
	 ACPI_FADT_OFFSET(pm1b_event_block),
88 89 90
	 ACPI_FADT_OFFSET(pm1_event_length),
	 ACPI_PM1_REGISTER_WIDTH * 2,	/* Enable + Status register */
	 0},
91

92 93
	{"Pm1aControlBlock",
	 ACPI_FADT_OFFSET(xpm1a_control_block),
94
	 ACPI_FADT_OFFSET(pm1a_control_block),
95 96 97
	 ACPI_FADT_OFFSET(pm1_control_length),
	 ACPI_PM1_REGISTER_WIDTH,
	 ACPI_FADT_REQUIRED},
98

99 100
	{"Pm1bControlBlock",
	 ACPI_FADT_OFFSET(xpm1b_control_block),
101
	 ACPI_FADT_OFFSET(pm1b_control_block),
102 103 104
	 ACPI_FADT_OFFSET(pm1_control_length),
	 ACPI_PM1_REGISTER_WIDTH,
	 0},
105

106 107
	{"Pm2ControlBlock",
	 ACPI_FADT_OFFSET(xpm2_control_block),
108
	 ACPI_FADT_OFFSET(pm2_control_block),
109 110 111
	 ACPI_FADT_OFFSET(pm2_control_length),
	 ACPI_PM2_REGISTER_WIDTH,
	 ACPI_FADT_SEPARATE_LENGTH},
112

113 114
	{"PmTimerBlock",
	 ACPI_FADT_OFFSET(xpm_timer_block),
115
	 ACPI_FADT_OFFSET(pm_timer_block),
116 117 118
	 ACPI_FADT_OFFSET(pm_timer_length),
	 ACPI_PM_TIMER_WIDTH,
	 ACPI_FADT_REQUIRED},
119

120 121
	{"Gpe0Block",
	 ACPI_FADT_OFFSET(xgpe0_block),
122
	 ACPI_FADT_OFFSET(gpe0_block),
123 124 125
	 ACPI_FADT_OFFSET(gpe0_block_length),
	 0,
	 ACPI_FADT_SEPARATE_LENGTH},
126

127 128
	{"Gpe1Block",
	 ACPI_FADT_OFFSET(xgpe1_block),
129
	 ACPI_FADT_OFFSET(gpe1_block),
130 131 132
	 ACPI_FADT_OFFSET(gpe1_block_length),
	 0,
	 ACPI_FADT_SEPARATE_LENGTH}
133 134
};

135
#define ACPI_FADT_INFO_ENTRIES        (sizeof (fadt_info_table) / sizeof (struct acpi_fadt_info))
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
/* 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))

166 167 168 169
/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_init_generic_address
 *
170
 * PARAMETERS:  generic_address     - GAS struct to be initialized
J
Jan Beulich 已提交
171
 *              byte_width          - Width of this register
172 173 174 175
 *              Address             - Address of the register
 *
 * RETURN:      None
 *
176 177 178
 * DESCRIPTION: Initialize a Generic Address Structure (GAS)
 *              See the ACPI specification for a full description and
 *              definition of this structure.
179 180 181
 *
 ******************************************************************************/

182
static inline void
183
acpi_tb_init_generic_address(struct acpi_generic_address *generic_address,
B
Bob Moore 已提交
184
			     u8 space_id, u8 byte_width, u64 address)
185 186
{

187 188 189 190 191 192 193 194
	/*
	 * 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 */

B
Bob Moore 已提交
195 196
	generic_address->space_id = space_id;
	generic_address->bit_width = (u8)ACPI_MUL_8(byte_width);
197
	generic_address->bit_offset = 0;
B
Bob Moore 已提交
198
	generic_address->access_width = 0;	/* Access width ANY */
199 200 201 202 203 204 205 206 207 208 209 210 211 212 213
}

/*******************************************************************************
 *
 * 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)
 *
 ******************************************************************************/

214
void acpi_tb_parse_fadt(u32 table_index)
215 216 217 218 219
{
	u32 length;
	struct acpi_table_header *table;

	/*
220 221
	 * The FADT has multiple versions with different lengths,
	 * and it contains pointers to both the DSDT and FACS tables.
222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240
	 *
	 * 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);

241
	/* Create a local copy of the FADT in common ACPI 2.0+ format */
242 243 244 245 246 247 248 249 250 251

	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,
252
			      ACPI_SIG_DSDT, ACPI_TABLE_INDEX_DSDT);
253 254

	acpi_tb_install_table((acpi_physical_address) acpi_gbl_FADT.Xfacs,
255
			      ACPI_SIG_FACS, ACPI_TABLE_INDEX_FACS);
256 257 258 259 260 261 262 263 264 265 266 267 268 269
}

/*******************************************************************************
 *
 * 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.
 *
270 271
 * NOTE:        We create a local copy of the FADT regardless of the version.
 *
272 273 274 275 276
 ******************************************************************************/

void acpi_tb_create_local_fadt(struct acpi_table_header *table, u32 length)
{

277
	/*
278 279 280
	 * Check if the FADT is larger than the largest table that we expect
	 * (the ACPI 2.0/3.0 version). If so, truncate the table, and issue
	 * a warning.
281 282 283
	 */
	if (length > sizeof(struct acpi_table_fadt)) {
		ACPI_WARNING((AE_INFO,
B
Bob Moore 已提交
284 285
			      "FADT (revision %u) is longer than ACPI 2.0 version, "
			      "truncating length 0x%X to 0x%zX",
286
			      table->revision, (unsigned)length,
287 288
			      sizeof(struct acpi_table_fadt)));
	}
289

290
	/* Clear the entire local FADT */
291

292
	ACPI_MEMSET(&acpi_gbl_FADT, 0, sizeof(struct acpi_table_fadt));
293

294 295
	/* Copy the original FADT, up to sizeof (struct acpi_table_fadt) */

296 297 298
	ACPI_MEMCPY(&acpi_gbl_FADT, table,
		    ACPI_MIN(length, sizeof(struct acpi_table_fadt)));

299 300
	/* Convert the local copy of the FADT to the common internal format */

301
	acpi_tb_convert_fadt();
302 303 304 305 306 307 308 309

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

	acpi_tb_validate_fadt();

	/* Initialize the global ACPI register structures */

	acpi_tb_setup_fadt_registers();
310 311 312 313 314 315 316 317 318 319 320
}

/*******************************************************************************
 *
 * 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.
321
 *              Expand all 32-bit addresses to 64-bit.
322
 *
B
Bob Moore 已提交
323 324
 * NOTE:        acpi_gbl_FADT must be of size (struct acpi_table_fadt),
 *              and must contain a copy of the actual FADT.
325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340
 *
 * ACPICA will use the "X" fields of the FADT for all addresses.
 *
 * "X" fields are optional extensions to the original V1.0 fields. Even if
 * they are present in the structure, they can be optionally not used by
 * setting them to zero. Therefore, we must selectively expand V1.0 fields
 * if the corresponding X field is zero.
 *
 * For ACPI 1.0 FADTs, all address fields are expanded to the corresponding
 * "X" fields.
 *
 * For ACPI 2.0 FADTs, any "X" fields that are NULL are filled in by
 * expanding the corresponding ACPI 1.0 field.
 *
 ******************************************************************************/

341
static void acpi_tb_convert_fadt(void)
342
{
343
	struct acpi_generic_address *target64;
344
	u32 i;
345

346 347 348 349
	/* Update the local FADT table header length */

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

350 351 352 353 354 355 356
	/*
	 * 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.
	 */
357 358
	if (!acpi_gbl_FADT.Xfacs) {
		acpi_gbl_FADT.Xfacs = (u64) acpi_gbl_FADT.facs;
359 360 361 362
	} 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!"));
363 364 365 366
	}

	if (!acpi_gbl_FADT.Xdsdt) {
		acpi_gbl_FADT.Xdsdt = (u64) acpi_gbl_FADT.dsdt;
367 368 369 370
	} 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!"));
371 372 373
	}

	/*
374 375 376 377 378 379 380
	 * 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.
	 */
381
	if (acpi_gbl_FADT.header.revision < FADT2_REVISION_ID) {
382 383 384 385 386 387 388
		acpi_gbl_FADT.preferred_profile = 0;
		acpi_gbl_FADT.pstate_control = 0;
		acpi_gbl_FADT.cst_control = 0;
		acpi_gbl_FADT.boot_flags = 0;
	}

	/*
389 390 391
	 * 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.
392
	 */
393
	for (i = 0; i < ACPI_FADT_INFO_ENTRIES; i++) {
394
		target64 =
395
		    ACPI_ADD_PTR(struct acpi_generic_address, &acpi_gbl_FADT,
396
				 fadt_info_table[i].address64);
397

398
		/* Expand only if the 64-bit X target is null */
399

400
		if (!target64->address) {
B
Bob Moore 已提交
401

402
			/* The space_id is always I/O for the 32-bit legacy address fields */
B
Bob Moore 已提交
403

404
			acpi_tb_init_generic_address(target64,
B
Bob Moore 已提交
405
						     ACPI_ADR_SPACE_SYSTEM_IO,
406 407
						     *ACPI_ADD_PTR(u8,
								   &acpi_gbl_FADT,
408
								   fadt_info_table
409 410 411
								   [i].length),
						     (u64) * ACPI_ADD_PTR(u32,
									  &acpi_gbl_FADT,
412
									  fadt_info_table
413
									  [i].
414
									  address32));
415 416 417 418 419 420 421 422
		}
	}
}

/******************************************************************************
 *
 * FUNCTION:    acpi_tb_validate_fadt
 *
423
 * PARAMETERS:  Table           - Pointer to the FADT to be validated
424
 *
B
Bob Moore 已提交
425
 * RETURN:      None
426
 *
427 428 429 430 431 432 433 434 435
 * 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
436 437 438
 *
 ******************************************************************************/

439
static void acpi_tb_validate_fadt(void)
440
{
B
Bob Moore 已提交
441
	char *name;
442 443 444
	u32 *address32;
	struct acpi_generic_address *address64;
	u8 length;
445
	u32 i;
446

B
Bob Moore 已提交
447 448 449 450 451 452 453 454
	/*
	 * 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,
455
			      "32/64X FACS address mismatch in FADT - "
B
Bob Moore 已提交
456 457 458 459
			      "two FACS tables! %8.8X/%8.8X%8.8X",
			      acpi_gbl_FADT.facs,
			      ACPI_FORMAT_UINT64(acpi_gbl_FADT.Xfacs)));
	}
460

B
Bob Moore 已提交
461 462 463
	if (acpi_gbl_FADT.dsdt &&
	    (acpi_gbl_FADT.Xdsdt != (u64) acpi_gbl_FADT.dsdt)) {
		ACPI_WARNING((AE_INFO,
464
			      "32/64X DSDT address mismatch in FADT - "
B
Bob Moore 已提交
465 466 467 468
			      "two DSDT tables! %8.8X/%8.8X%8.8X",
			      acpi_gbl_FADT.dsdt,
			      ACPI_FORMAT_UINT64(acpi_gbl_FADT.Xdsdt)));
	}
469

B
Bob Moore 已提交
470
	/* Examine all of the 64-bit extended address fields (X fields) */
471

B
Bob Moore 已提交
472 473 474 475 476 477 478
	for (i = 0; i < ACPI_FADT_INFO_ENTRIES; i++) {
		/*
		 * Generate pointers to the 32-bit and 64-bit addresses, get the
		 * register length (width), and the register name
		 */
		address64 = ACPI_ADD_PTR(struct acpi_generic_address,
					 &acpi_gbl_FADT,
479
					 fadt_info_table[i].address64);
480 481
		address32 =
		    ACPI_ADD_PTR(u32, &acpi_gbl_FADT,
482
				 fadt_info_table[i].address32);
483 484 485
		length =
		    *ACPI_ADD_PTR(u8, &acpi_gbl_FADT,
				  fadt_info_table[i].length);
B
Bob Moore 已提交
486 487 488 489
		name = fadt_info_table[i].name;

		/*
		 * For each extended field, check for length mismatch between the
490
		 * legacy length field and the corresponding 64-bit X length field.
B
Bob Moore 已提交
491 492 493
		 */
		if (address64 && (address64->bit_width != ACPI_MUL_8(length))) {
			ACPI_WARNING((AE_INFO,
494
				      "32/64X length mismatch in %s: %d/%d",
B
Bob Moore 已提交
495 496 497
				      name, ACPI_MUL_8(length),
				      address64->bit_width));
		}
498 499 500 501 502 503 504 505

		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,
B
Bob Moore 已提交
506 507
					    "Required field %s has zero address and/or length: %8.8X%8.8X/%X",
					    name,
508 509 510 511 512 513 514 515 516 517 518 519
					    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,
B
Bob Moore 已提交
520 521
					      "Optional field %s has zero address or length: %8.8X%8.8X/%X",
					      name,
522 523 524 525 526
					      ACPI_FORMAT_UINT64(address64->
								 address),
					      length));
			}
		}
527

528
		/* If both 32- and 64-bit addresses are valid (non-zero), they must match */
529

530 531 532
		if (address64->address && *address32 &&
		    (address64->address != (u64) * address32)) {
			ACPI_ERROR((AE_INFO,
533
				    "32/64X address mismatch in %s: %8.8X/%8.8X%8.8X, using 64X",
B
Bob Moore 已提交
534
				    name, *address32,
535 536
				    ACPI_FORMAT_UINT64(address64->address)));
		}
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

/******************************************************************************
 *
 * 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: %d, using default %d",
					      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);

621 622 623 624 625 626 627 628 629
		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));
		}
630 631
	}
}