1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /******************************************************************************
3 *
4 * Module Name: tbfadt - FADT table utilities
5 *
6 * Copyright (C) 2000 - 2023, Intel Corp.
7 *
8 *****************************************************************************/
9
10 #include <acpi/acpi.h>
11 #include "accommon.h"
12 #include "actables.h"
13
14 #define _COMPONENT ACPI_TABLES
15 ACPI_MODULE_NAME("tbfadt")
16
17 /* Local prototypes */
18 static void
19 acpi_tb_init_generic_address(struct acpi_generic_address *generic_address,
20 u8 space_id,
21 u8 byte_width,
22 u64 address, const char *register_name, u8 flags);
23
24 static void acpi_tb_convert_fadt(void);
25
26 static void acpi_tb_setup_fadt_registers(void);
27
28 static u64
29 acpi_tb_select_address(char *register_name, u32 address32, u64 address64);
30
31 /* Table for conversion of FADT to common internal format and FADT validation */
32
33 typedef struct acpi_fadt_info {
34 const char *name;
35 u16 address64;
36 u16 address32;
37 u16 length;
38 u8 default_length;
39 u8 flags;
40
41 } acpi_fadt_info;
42
43 #define ACPI_FADT_OPTIONAL 0
44 #define ACPI_FADT_REQUIRED 1
45 #define ACPI_FADT_SEPARATE_LENGTH 2
46 #define ACPI_FADT_GPE_REGISTER 4
47
48 static struct acpi_fadt_info fadt_info_table[] = {
49 {"Pm1aEventBlock",
50 ACPI_FADT_OFFSET(xpm1a_event_block),
51 ACPI_FADT_OFFSET(pm1a_event_block),
52 ACPI_FADT_OFFSET(pm1_event_length),
53 ACPI_PM1_REGISTER_WIDTH * 2, /* Enable + Status register */
54 ACPI_FADT_REQUIRED},
55
56 {"Pm1bEventBlock",
57 ACPI_FADT_OFFSET(xpm1b_event_block),
58 ACPI_FADT_OFFSET(pm1b_event_block),
59 ACPI_FADT_OFFSET(pm1_event_length),
60 ACPI_PM1_REGISTER_WIDTH * 2, /* Enable + Status register */
61 ACPI_FADT_OPTIONAL},
62
63 {"Pm1aControlBlock",
64 ACPI_FADT_OFFSET(xpm1a_control_block),
65 ACPI_FADT_OFFSET(pm1a_control_block),
66 ACPI_FADT_OFFSET(pm1_control_length),
67 ACPI_PM1_REGISTER_WIDTH,
68 ACPI_FADT_REQUIRED},
69
70 {"Pm1bControlBlock",
71 ACPI_FADT_OFFSET(xpm1b_control_block),
72 ACPI_FADT_OFFSET(pm1b_control_block),
73 ACPI_FADT_OFFSET(pm1_control_length),
74 ACPI_PM1_REGISTER_WIDTH,
75 ACPI_FADT_OPTIONAL},
76
77 {"Pm2ControlBlock",
78 ACPI_FADT_OFFSET(xpm2_control_block),
79 ACPI_FADT_OFFSET(pm2_control_block),
80 ACPI_FADT_OFFSET(pm2_control_length),
81 ACPI_PM2_REGISTER_WIDTH,
82 ACPI_FADT_SEPARATE_LENGTH},
83
84 {"PmTimerBlock",
85 ACPI_FADT_OFFSET(xpm_timer_block),
86 ACPI_FADT_OFFSET(pm_timer_block),
87 ACPI_FADT_OFFSET(pm_timer_length),
88 ACPI_PM_TIMER_WIDTH,
89 ACPI_FADT_SEPARATE_LENGTH}, /* ACPI 5.0A: Timer is optional */
90
91 {"Gpe0Block",
92 ACPI_FADT_OFFSET(xgpe0_block),
93 ACPI_FADT_OFFSET(gpe0_block),
94 ACPI_FADT_OFFSET(gpe0_block_length),
95 0,
96 ACPI_FADT_SEPARATE_LENGTH | ACPI_FADT_GPE_REGISTER},
97
98 {"Gpe1Block",
99 ACPI_FADT_OFFSET(xgpe1_block),
100 ACPI_FADT_OFFSET(gpe1_block),
101 ACPI_FADT_OFFSET(gpe1_block_length),
102 0,
103 ACPI_FADT_SEPARATE_LENGTH | ACPI_FADT_GPE_REGISTER}
104 };
105
106 #define ACPI_FADT_INFO_ENTRIES \
107 (sizeof (fadt_info_table) / sizeof (struct acpi_fadt_info))
108
109 /* Table used to split Event Blocks into separate status/enable registers */
110
111 typedef struct acpi_fadt_pm_info {
112 struct acpi_generic_address *target;
113 u16 source;
114 u8 register_num;
115
116 } acpi_fadt_pm_info;
117
118 static struct acpi_fadt_pm_info fadt_pm_info_table[] = {
119 {&acpi_gbl_xpm1a_status,
120 ACPI_FADT_OFFSET(xpm1a_event_block),
121 0},
122
123 {&acpi_gbl_xpm1a_enable,
124 ACPI_FADT_OFFSET(xpm1a_event_block),
125 1},
126
127 {&acpi_gbl_xpm1b_status,
128 ACPI_FADT_OFFSET(xpm1b_event_block),
129 0},
130
131 {&acpi_gbl_xpm1b_enable,
132 ACPI_FADT_OFFSET(xpm1b_event_block),
133 1}
134 };
135
136 #define ACPI_FADT_PM_INFO_ENTRIES \
137 (sizeof (fadt_pm_info_table) / sizeof (struct acpi_fadt_pm_info))
138
139 /*******************************************************************************
140 *
141 * FUNCTION: acpi_tb_init_generic_address
142 *
143 * PARAMETERS: generic_address - GAS struct to be initialized
144 * space_id - ACPI Space ID for this register
145 * byte_width - Width of this register
146 * address - Address of the register
147 * register_name - ASCII name of the ACPI register
148 *
149 * RETURN: None
150 *
151 * DESCRIPTION: Initialize a Generic Address Structure (GAS)
152 * See the ACPI specification for a full description and
153 * definition of this structure.
154 *
155 ******************************************************************************/
156
157 static void
acpi_tb_init_generic_address(struct acpi_generic_address * generic_address,u8 space_id,u8 byte_width,u64 address,const char * register_name,u8 flags)158 acpi_tb_init_generic_address(struct acpi_generic_address *generic_address,
159 u8 space_id,
160 u8 byte_width,
161 u64 address, const char *register_name, u8 flags)
162 {
163 u8 bit_width;
164
165 /*
166 * Bit width field in the GAS is only one byte long, 255 max.
167 * Check for bit_width overflow in GAS.
168 */
169 bit_width = (u8)(byte_width * 8);
170 if (byte_width > 31) { /* (31*8)=248, (32*8)=256 */
171 /*
172 * No error for GPE blocks, because we do not use the bit_width
173 * for GPEs, the legacy length (byte_width) is used instead to
174 * allow for a large number of GPEs.
175 */
176 if (!(flags & ACPI_FADT_GPE_REGISTER)) {
177 ACPI_ERROR((AE_INFO,
178 "%s - 32-bit FADT register is too long (%u bytes, %u bits) "
179 "to convert to GAS struct - 255 bits max, truncating",
180 register_name, byte_width,
181 (byte_width * 8)));
182 }
183
184 bit_width = 255;
185 }
186
187 /*
188 * The 64-bit Address field is non-aligned in the byte packed
189 * GAS struct.
190 */
191 ACPI_MOVE_64_TO_64(&generic_address->address, &address);
192
193 /* All other fields are byte-wide */
194
195 generic_address->space_id = space_id;
196 generic_address->bit_width = bit_width;
197 generic_address->bit_offset = 0;
198 generic_address->access_width = 0; /* Access width ANY */
199 }
200
201 /*******************************************************************************
202 *
203 * FUNCTION: acpi_tb_select_address
204 *
205 * PARAMETERS: register_name - ASCII name of the ACPI register
206 * address32 - 32-bit address of the register
207 * address64 - 64-bit address of the register
208 *
209 * RETURN: The resolved 64-bit address
210 *
211 * DESCRIPTION: Select between 32-bit and 64-bit versions of addresses within
212 * the FADT. Used for the FACS and DSDT addresses.
213 *
214 * NOTES:
215 *
216 * Check for FACS and DSDT address mismatches. An address mismatch between
217 * the 32-bit and 64-bit address fields (FIRMWARE_CTRL/X_FIRMWARE_CTRL and
218 * DSDT/X_DSDT) could be a corrupted address field or it might indicate
219 * the presence of two FACS or two DSDT tables.
220 *
221 * November 2013:
222 * By default, as per the ACPICA specification, a valid 64-bit address is
223 * used regardless of the value of the 32-bit address. However, this
224 * behavior can be overridden via the acpi_gbl_use32_bit_fadt_addresses flag.
225 *
226 ******************************************************************************/
227
228 static u64
acpi_tb_select_address(char * register_name,u32 address32,u64 address64)229 acpi_tb_select_address(char *register_name, u32 address32, u64 address64)
230 {
231
232 if (!address64) {
233
234 /* 64-bit address is zero, use 32-bit address */
235
236 return ((u64)address32);
237 }
238
239 if (address32 && (address64 != (u64)address32)) {
240
241 /* Address mismatch between 32-bit and 64-bit versions */
242
243 ACPI_BIOS_WARNING((AE_INFO,
244 "32/64X %s address mismatch in FADT: "
245 "0x%8.8X/0x%8.8X%8.8X, using %u-bit address",
246 register_name, address32,
247 ACPI_FORMAT_UINT64(address64),
248 acpi_gbl_use32_bit_fadt_addresses ? 32 :
249 64));
250
251 /* 32-bit address override */
252
253 if (acpi_gbl_use32_bit_fadt_addresses) {
254 return ((u64)address32);
255 }
256 }
257
258 /* Default is to use the 64-bit address */
259
260 return (address64);
261 }
262
263 /*******************************************************************************
264 *
265 * FUNCTION: acpi_tb_parse_fadt
266 *
267 * PARAMETERS: None
268 *
269 * RETURN: None
270 *
271 * DESCRIPTION: Initialize the FADT, DSDT and FACS tables
272 * (FADT contains the addresses of the DSDT and FACS)
273 *
274 ******************************************************************************/
275
acpi_tb_parse_fadt(void)276 void acpi_tb_parse_fadt(void)
277 {
278 u32 length;
279 struct acpi_table_header *table;
280 struct acpi_table_desc *fadt_desc;
281 acpi_status status;
282
283 /*
284 * The FADT has multiple versions with different lengths,
285 * and it contains pointers to both the DSDT and FACS tables.
286 *
287 * Get a local copy of the FADT and convert it to a common format
288 * Map entire FADT, assumed to be smaller than one page.
289 */
290 fadt_desc = &acpi_gbl_root_table_list.tables[acpi_gbl_fadt_index];
291 status = acpi_tb_get_table(fadt_desc, &table);
292 if (ACPI_FAILURE(status)) {
293 return;
294 }
295 length = fadt_desc->length;
296
297 /*
298 * Validate the FADT checksum before we copy the table. Ignore
299 * checksum error as we want to try to get the DSDT and FACS.
300 */
301 (void)acpi_ut_verify_checksum(table, length);
302
303 /* Create a local copy of the FADT in common ACPI 2.0+ format */
304
305 acpi_tb_create_local_fadt(table, length);
306
307 /* All done with the real FADT, unmap it */
308
309 acpi_tb_put_table(fadt_desc);
310
311 /* Obtain the DSDT and FACS tables via their addresses within the FADT */
312
313 acpi_tb_install_standard_table((acpi_physical_address)acpi_gbl_FADT.
314 Xdsdt,
315 ACPI_TABLE_ORIGIN_INTERNAL_PHYSICAL,
316 NULL, FALSE, TRUE, &acpi_gbl_dsdt_index);
317
318 if (acpi_gbl_FADT.facs) {
319 acpi_tb_install_standard_table((acpi_physical_address)
320 acpi_gbl_FADT.facs,
321 ACPI_TABLE_ORIGIN_INTERNAL_PHYSICAL,
322 NULL, FALSE, TRUE,
323 &acpi_gbl_facs_index);
324 }
325 if (acpi_gbl_FADT.Xfacs) {
326 acpi_tb_install_standard_table((acpi_physical_address)
327 acpi_gbl_FADT.Xfacs,
328 ACPI_TABLE_ORIGIN_INTERNAL_PHYSICAL,
329 NULL, FALSE, TRUE,
330 &acpi_gbl_xfacs_index);
331 }
332 }
333
334 /*******************************************************************************
335 *
336 * FUNCTION: acpi_tb_create_local_fadt
337 *
338 * PARAMETERS: table - Pointer to BIOS FADT
339 * length - Length of the table
340 *
341 * RETURN: None
342 *
343 * DESCRIPTION: Get a local copy of the FADT and convert it to a common format.
344 * Performs validation on some important FADT fields.
345 *
346 * NOTE: We create a local copy of the FADT regardless of the version.
347 *
348 ******************************************************************************/
349
acpi_tb_create_local_fadt(struct acpi_table_header * table,u32 length)350 void acpi_tb_create_local_fadt(struct acpi_table_header *table, u32 length)
351 {
352 /*
353 * Check if the FADT is larger than the largest table that we expect
354 * (typically the current ACPI specification version). If so, truncate
355 * the table, and issue a warning.
356 */
357 if (length > sizeof(struct acpi_table_fadt)) {
358 ACPI_BIOS_WARNING((AE_INFO,
359 "FADT (revision %u) is longer than %s length, "
360 "truncating length %u to %u",
361 table->revision, ACPI_FADT_CONFORMANCE,
362 length,
363 (u32)sizeof(struct acpi_table_fadt)));
364 }
365
366 /* Clear the entire local FADT */
367
368 memset(&acpi_gbl_FADT, 0, sizeof(struct acpi_table_fadt));
369
370 /* Copy the original FADT, up to sizeof (struct acpi_table_fadt) */
371
372 memcpy(&acpi_gbl_FADT, table,
373 ACPI_MIN(length, sizeof(struct acpi_table_fadt)));
374
375 /* Take a copy of the Hardware Reduced flag */
376
377 acpi_gbl_reduced_hardware = FALSE;
378 if (acpi_gbl_FADT.flags & ACPI_FADT_HW_REDUCED) {
379 acpi_gbl_reduced_hardware = TRUE;
380 }
381
382 /* Convert the local copy of the FADT to the common internal format */
383
384 acpi_tb_convert_fadt();
385
386 /* Initialize the global ACPI register structures */
387
388 acpi_tb_setup_fadt_registers();
389 }
390
391 /*******************************************************************************
392 *
393 * FUNCTION: acpi_tb_convert_fadt
394 *
395 * PARAMETERS: none - acpi_gbl_FADT is used.
396 *
397 * RETURN: None
398 *
399 * DESCRIPTION: Converts all versions of the FADT to a common internal format.
400 * Expand 32-bit addresses to 64-bit as necessary. Also validate
401 * important fields within the FADT.
402 *
403 * NOTE: acpi_gbl_FADT must be of size (struct acpi_table_fadt), and must
404 * contain a copy of the actual BIOS-provided FADT.
405 *
406 * Notes on 64-bit register addresses:
407 *
408 * After this FADT conversion, later ACPICA code will only use the 64-bit "X"
409 * fields of the FADT for all ACPI register addresses.
410 *
411 * The 64-bit X fields are optional extensions to the original 32-bit FADT
412 * V1.0 fields. Even if they are present in the FADT, they are optional and
413 * are unused if the BIOS sets them to zero. Therefore, we must copy/expand
414 * 32-bit V1.0 fields to the 64-bit X fields if the 64-bit X field is originally
415 * zero.
416 *
417 * For ACPI 1.0 FADTs (that contain no 64-bit addresses), all 32-bit address
418 * fields are expanded to the corresponding 64-bit X fields in the internal
419 * common FADT.
420 *
421 * For ACPI 2.0+ FADTs, all valid (non-zero) 32-bit address fields are expanded
422 * to the corresponding 64-bit X fields, if the 64-bit field is originally
423 * zero. Adhering to the ACPI specification, we completely ignore the 32-bit
424 * field if the 64-bit field is valid, regardless of whether the host OS is
425 * 32-bit or 64-bit.
426 *
427 * Possible additional checks:
428 * (acpi_gbl_FADT.pm1_event_length >= 4)
429 * (acpi_gbl_FADT.pm1_control_length >= 2)
430 * (acpi_gbl_FADT.pm_timer_length >= 4)
431 * Gpe block lengths must be multiple of 2
432 *
433 ******************************************************************************/
434
acpi_tb_convert_fadt(void)435 static void acpi_tb_convert_fadt(void)
436 {
437 const char *name;
438 struct acpi_generic_address *address64;
439 u32 address32;
440 u8 length;
441 u8 flags;
442 u32 i;
443
444 /*
445 * For ACPI 1.0 FADTs (revision 1 or 2), ensure that reserved fields which
446 * should be zero are indeed zero. This will workaround BIOSs that
447 * inadvertently place values in these fields.
448 *
449 * The ACPI 1.0 reserved fields that will be zeroed are the bytes located
450 * at offset 45, 55, 95, and the word located at offset 109, 110.
451 *
452 * Note: The FADT revision value is unreliable. Only the length can be
453 * trusted.
454 */
455 if (acpi_gbl_FADT.header.length <= ACPI_FADT_V2_SIZE) {
456 acpi_gbl_FADT.preferred_profile = 0;
457 acpi_gbl_FADT.pstate_control = 0;
458 acpi_gbl_FADT.cst_control = 0;
459 acpi_gbl_FADT.boot_flags = 0;
460 }
461
462 /*
463 * Now we can update the local FADT length to the length of the
464 * current FADT version as defined by the ACPI specification.
465 * Thus, we will have a common FADT internally.
466 */
467 acpi_gbl_FADT.header.length = sizeof(struct acpi_table_fadt);
468
469 /*
470 * Expand the 32-bit DSDT addresses to 64-bit as necessary.
471 * Later ACPICA code will always use the X 64-bit field.
472 */
473 acpi_gbl_FADT.Xdsdt = acpi_tb_select_address("DSDT",
474 acpi_gbl_FADT.dsdt,
475 acpi_gbl_FADT.Xdsdt);
476
477 /* If Hardware Reduced flag is set, we are all done */
478
479 if (acpi_gbl_reduced_hardware) {
480 return;
481 }
482
483 /* Examine all of the 64-bit extended address fields (X fields) */
484
485 for (i = 0; i < ACPI_FADT_INFO_ENTRIES; i++) {
486 /*
487 * Get the 32-bit and 64-bit addresses, as well as the register
488 * length and register name.
489 */
490 address32 = *ACPI_ADD_PTR(u32,
491 &acpi_gbl_FADT,
492 fadt_info_table[i].address32);
493
494 address64 = ACPI_ADD_PTR(struct acpi_generic_address,
495 &acpi_gbl_FADT,
496 fadt_info_table[i].address64);
497
498 length = *ACPI_ADD_PTR(u8,
499 &acpi_gbl_FADT,
500 fadt_info_table[i].length);
501
502 name = fadt_info_table[i].name;
503 flags = fadt_info_table[i].flags;
504
505 /*
506 * Expand the ACPI 1.0 32-bit addresses to the ACPI 2.0 64-bit "X"
507 * generic address structures as necessary. Later code will always use
508 * the 64-bit address structures.
509 *
510 * November 2013:
511 * Now always use the 64-bit address if it is valid (non-zero), in
512 * accordance with the ACPI specification which states that a 64-bit
513 * address supersedes the 32-bit version. This behavior can be
514 * overridden by the acpi_gbl_use32_bit_fadt_addresses flag.
515 *
516 * During 64-bit address construction and verification,
517 * these cases are handled:
518 *
519 * Address32 zero, Address64 [don't care] - Use Address64
520 *
521 * No override: if acpi_gbl_use32_bit_fadt_addresses is FALSE, and:
522 * Address32 non-zero, Address64 zero - Copy/use Address32
523 * Address32 non-zero == Address64 non-zero - Use Address64
524 * Address32 non-zero != Address64 non-zero - Warning, use Address64
525 *
526 * Override: if acpi_gbl_use32_bit_fadt_addresses is TRUE, and:
527 * Address32 non-zero, Address64 zero - Copy/use Address32
528 * Address32 non-zero == Address64 non-zero - Copy/use Address32
529 * Address32 non-zero != Address64 non-zero - Warning, copy/use Address32
530 *
531 * Note: space_id is always I/O for 32-bit legacy address fields
532 */
533 if (address32) {
534 if (address64->address) {
535 if (address64->address != (u64)address32) {
536
537 /* Address mismatch */
538
539 ACPI_BIOS_WARNING((AE_INFO,
540 "32/64X address mismatch in FADT/%s: "
541 "0x%8.8X/0x%8.8X%8.8X, using %u-bit address",
542 name, address32,
543 ACPI_FORMAT_UINT64
544 (address64->address),
545 acpi_gbl_use32_bit_fadt_addresses
546 ? 32 : 64));
547 }
548
549 /*
550 * For each extended field, check for length mismatch
551 * between the legacy length field and the corresponding
552 * 64-bit X length field.
553 * Note: If the legacy length field is > 0xFF bits, ignore
554 * this check. (GPE registers can be larger than the
555 * 64-bit GAS structure can accommodate, 0xFF bits).
556 */
557 if ((ACPI_MUL_8(length) <= ACPI_UINT8_MAX) &&
558 (address64->bit_width !=
559 ACPI_MUL_8(length))) {
560 ACPI_BIOS_WARNING((AE_INFO,
561 "32/64X length mismatch in FADT/%s: %u/%u",
562 name,
563 ACPI_MUL_8(length),
564 address64->
565 bit_width));
566 }
567 }
568
569 /*
570 * Hardware register access code always uses the 64-bit fields.
571 * So if the 64-bit field is zero or is to be overridden,
572 * initialize it with the 32-bit fields.
573 * Note that when the 32-bit address favor is specified, the
574 * 64-bit fields are always re-initialized so that
575 * access_size/bit_width/bit_offset fields can be correctly
576 * configured to the values to trigger a 32-bit compatible
577 * access mode in the hardware register access code.
578 */
579 if (!address64->address
580 || acpi_gbl_use32_bit_fadt_addresses) {
581 acpi_tb_init_generic_address(address64,
582 ACPI_ADR_SPACE_SYSTEM_IO,
583 length,
584 (u64)address32,
585 name, flags);
586 }
587 }
588
589 if (fadt_info_table[i].flags & ACPI_FADT_REQUIRED) {
590 /*
591 * Field is required (Pm1a_event, Pm1a_control).
592 * Both the address and length must be non-zero.
593 */
594 if (!address64->address || !length) {
595 ACPI_BIOS_ERROR((AE_INFO,
596 "Required FADT field %s has zero address and/or length: "
597 "0x%8.8X%8.8X/0x%X",
598 name,
599 ACPI_FORMAT_UINT64(address64->
600 address),
601 length));
602 }
603 } else if (fadt_info_table[i].flags & ACPI_FADT_SEPARATE_LENGTH) {
604 /*
605 * Field is optional (Pm2_control, GPE0, GPE1) AND has its own
606 * length field. If present, both the address and length must
607 * be valid.
608 */
609 if ((address64->address && !length) ||
610 (!address64->address && length)) {
611 ACPI_BIOS_WARNING((AE_INFO,
612 "Optional FADT field %s has valid %s but zero %s: "
613 "0x%8.8X%8.8X/0x%X", name,
614 (length ? "Length" :
615 "Address"),
616 (length ? "Address" :
617 "Length"),
618 ACPI_FORMAT_UINT64
619 (address64->address),
620 length));
621 }
622 }
623 }
624 }
625
626 /*******************************************************************************
627 *
628 * FUNCTION: acpi_tb_setup_fadt_registers
629 *
630 * PARAMETERS: None, uses acpi_gbl_FADT.
631 *
632 * RETURN: None
633 *
634 * DESCRIPTION: Initialize global ACPI PM1 register definitions. Optionally,
635 * force FADT register definitions to their default lengths.
636 *
637 ******************************************************************************/
638
acpi_tb_setup_fadt_registers(void)639 static void acpi_tb_setup_fadt_registers(void)
640 {
641 struct acpi_generic_address *target64;
642 struct acpi_generic_address *source64;
643 u8 pm1_register_byte_width;
644 u32 i;
645
646 /*
647 * Optionally check all register lengths against the default values and
648 * update them if they are incorrect.
649 */
650 if (acpi_gbl_use_default_register_widths) {
651 for (i = 0; i < ACPI_FADT_INFO_ENTRIES; i++) {
652 target64 =
653 ACPI_ADD_PTR(struct acpi_generic_address,
654 &acpi_gbl_FADT,
655 fadt_info_table[i].address64);
656
657 /*
658 * If a valid register (Address != 0) and the (default_length > 0)
659 * (Not a GPE register), then check the width against the default.
660 */
661 if ((target64->address) &&
662 (fadt_info_table[i].default_length > 0) &&
663 (fadt_info_table[i].default_length !=
664 target64->bit_width)) {
665 ACPI_BIOS_WARNING((AE_INFO,
666 "Invalid length for FADT/%s: %u, using default %u",
667 fadt_info_table[i].name,
668 target64->bit_width,
669 fadt_info_table[i].
670 default_length));
671
672 /* Incorrect size, set width to the default */
673
674 target64->bit_width =
675 fadt_info_table[i].default_length;
676 }
677 }
678 }
679
680 /*
681 * Get the length of the individual PM1 registers (enable and status).
682 * Each register is defined to be (event block length / 2). Extra divide
683 * by 8 converts bits to bytes.
684 */
685 pm1_register_byte_width = (u8)
686 ACPI_DIV_16(acpi_gbl_FADT.xpm1a_event_block.bit_width);
687
688 /*
689 * Calculate separate GAS structs for the PM1x (A/B) Status and Enable
690 * registers. These addresses do not appear (directly) in the FADT, so it
691 * is useful to pre-calculate them from the PM1 Event Block definitions.
692 *
693 * The PM event blocks are split into two register blocks, first is the
694 * PM Status Register block, followed immediately by the PM Enable
695 * Register block. Each is of length (pm1_event_length/2)
696 *
697 * Note: The PM1A event block is required by the ACPI specification.
698 * However, the PM1B event block is optional and is rarely, if ever,
699 * used.
700 */
701
702 for (i = 0; i < ACPI_FADT_PM_INFO_ENTRIES; i++) {
703 source64 =
704 ACPI_ADD_PTR(struct acpi_generic_address, &acpi_gbl_FADT,
705 fadt_pm_info_table[i].source);
706
707 if (source64->address) {
708 acpi_tb_init_generic_address(fadt_pm_info_table[i].
709 target, source64->space_id,
710 pm1_register_byte_width,
711 source64->address +
712 (fadt_pm_info_table[i].
713 register_num *
714 pm1_register_byte_width),
715 "PmRegisters", 0);
716 }
717 }
718 }
719