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 - 2019, 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
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
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
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_tb_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 FALSE, TRUE, &acpi_gbl_dsdt_index);
317
318 /* If Hardware Reduced flag is set, there is no FACS */
319
320 if (!acpi_gbl_reduced_hardware) {
321 if (acpi_gbl_FADT.facs) {
322 acpi_tb_install_standard_table((acpi_physical_address)
323 acpi_gbl_FADT.facs,
324 ACPI_TABLE_ORIGIN_INTERNAL_PHYSICAL,
325 FALSE, TRUE,
326 &acpi_gbl_facs_index);
327 }
328 if (acpi_gbl_FADT.Xfacs) {
329 acpi_tb_install_standard_table((acpi_physical_address)
330 acpi_gbl_FADT.Xfacs,
331 ACPI_TABLE_ORIGIN_INTERNAL_PHYSICAL,
332 FALSE, TRUE,
333 &acpi_gbl_xfacs_index);
334 }
335 }
336 }
337
338 /*******************************************************************************
339 *
340 * FUNCTION: acpi_tb_create_local_fadt
341 *
342 * PARAMETERS: table - Pointer to BIOS FADT
343 * length - Length of the table
344 *
345 * RETURN: None
346 *
347 * DESCRIPTION: Get a local copy of the FADT and convert it to a common format.
348 * Performs validation on some important FADT fields.
349 *
350 * NOTE: We create a local copy of the FADT regardless of the version.
351 *
352 ******************************************************************************/
353
354 void acpi_tb_create_local_fadt(struct acpi_table_header *table, u32 length)
355 {
356 /*
357 * Check if the FADT is larger than the largest table that we expect
358 * (typically the current ACPI specification version). If so, truncate
359 * the table, and issue a warning.
360 */
361 if (length > sizeof(struct acpi_table_fadt)) {
362 ACPI_BIOS_WARNING((AE_INFO,
363 "FADT (revision %u) is longer than %s length, "
364 "truncating length %u to %u",
365 table->revision, ACPI_FADT_CONFORMANCE,
366 length,
367 (u32)sizeof(struct acpi_table_fadt)));
368 }
369
370 /* Clear the entire local FADT */
371
372 memset(&acpi_gbl_FADT, 0, sizeof(struct acpi_table_fadt));
373
374 /* Copy the original FADT, up to sizeof (struct acpi_table_fadt) */
375
376 memcpy(&acpi_gbl_FADT, table,
377 ACPI_MIN(length, sizeof(struct acpi_table_fadt)));
378
379 /* Take a copy of the Hardware Reduced flag */
380
381 acpi_gbl_reduced_hardware = FALSE;
382 if (acpi_gbl_FADT.flags & ACPI_FADT_HW_REDUCED) {
383 acpi_gbl_reduced_hardware = TRUE;
384 }
385
386 /* Convert the local copy of the FADT to the common internal format */
387
388 acpi_tb_convert_fadt();
389
390 /* Initialize the global ACPI register structures */
391
392 acpi_tb_setup_fadt_registers();
393 }
394
395 /*******************************************************************************
396 *
397 * FUNCTION: acpi_tb_convert_fadt
398 *
399 * PARAMETERS: none - acpi_gbl_FADT is used.
400 *
401 * RETURN: None
402 *
403 * DESCRIPTION: Converts all versions of the FADT to a common internal format.
404 * Expand 32-bit addresses to 64-bit as necessary. Also validate
405 * important fields within the FADT.
406 *
407 * NOTE: acpi_gbl_FADT must be of size (struct acpi_table_fadt), and must
408 * contain a copy of the actual BIOS-provided FADT.
409 *
410 * Notes on 64-bit register addresses:
411 *
412 * After this FADT conversion, later ACPICA code will only use the 64-bit "X"
413 * fields of the FADT for all ACPI register addresses.
414 *
415 * The 64-bit X fields are optional extensions to the original 32-bit FADT
416 * V1.0 fields. Even if they are present in the FADT, they are optional and
417 * are unused if the BIOS sets them to zero. Therefore, we must copy/expand
418 * 32-bit V1.0 fields to the 64-bit X fields if the 64-bit X field is originally
419 * zero.
420 *
421 * For ACPI 1.0 FADTs (that contain no 64-bit addresses), all 32-bit address
422 * fields are expanded to the corresponding 64-bit X fields in the internal
423 * common FADT.
424 *
425 * For ACPI 2.0+ FADTs, all valid (non-zero) 32-bit address fields are expanded
426 * to the corresponding 64-bit X fields, if the 64-bit field is originally
427 * zero. Adhering to the ACPI specification, we completely ignore the 32-bit
428 * field if the 64-bit field is valid, regardless of whether the host OS is
429 * 32-bit or 64-bit.
430 *
431 * Possible additional checks:
432 * (acpi_gbl_FADT.pm1_event_length >= 4)
433 * (acpi_gbl_FADT.pm1_control_length >= 2)
434 * (acpi_gbl_FADT.pm_timer_length >= 4)
435 * Gpe block lengths must be multiple of 2
436 *
437 ******************************************************************************/
438
439 static void acpi_tb_convert_fadt(void)
440 {
441 const char *name;
442 struct acpi_generic_address *address64;
443 u32 address32;
444 u8 length;
445 u8 flags;
446 u32 i;
447
448 /*
449 * For ACPI 1.0 FADTs (revision 1 or 2), ensure that reserved fields which
450 * should be zero are indeed zero. This will workaround BIOSs that
451 * inadvertently place values in these fields.
452 *
453 * The ACPI 1.0 reserved fields that will be zeroed are the bytes located
454 * at offset 45, 55, 95, and the word located at offset 109, 110.
455 *
456 * Note: The FADT revision value is unreliable. Only the length can be
457 * trusted.
458 */
459 if (acpi_gbl_FADT.header.length <= ACPI_FADT_V2_SIZE) {
460 acpi_gbl_FADT.preferred_profile = 0;
461 acpi_gbl_FADT.pstate_control = 0;
462 acpi_gbl_FADT.cst_control = 0;
463 acpi_gbl_FADT.boot_flags = 0;
464 }
465
466 /*
467 * Now we can update the local FADT length to the length of the
468 * current FADT version as defined by the ACPI specification.
469 * Thus, we will have a common FADT internally.
470 */
471 acpi_gbl_FADT.header.length = sizeof(struct acpi_table_fadt);
472
473 /*
474 * Expand the 32-bit DSDT addresses to 64-bit as necessary.
475 * Later ACPICA code will always use the X 64-bit field.
476 */
477 acpi_gbl_FADT.Xdsdt = acpi_tb_select_address("DSDT",
478 acpi_gbl_FADT.dsdt,
479 acpi_gbl_FADT.Xdsdt);
480
481 /* If Hardware Reduced flag is set, we are all done */
482
483 if (acpi_gbl_reduced_hardware) {
484 return;
485 }
486
487 /* Examine all of the 64-bit extended address fields (X fields) */
488
489 for (i = 0; i < ACPI_FADT_INFO_ENTRIES; i++) {
490 /*
491 * Get the 32-bit and 64-bit addresses, as well as the register
492 * length and register name.
493 */
494 address32 = *ACPI_ADD_PTR(u32,
495 &acpi_gbl_FADT,
496 fadt_info_table[i].address32);
497
498 address64 = ACPI_ADD_PTR(struct acpi_generic_address,
499 &acpi_gbl_FADT,
500 fadt_info_table[i].address64);
501
502 length = *ACPI_ADD_PTR(u8,
503 &acpi_gbl_FADT,
504 fadt_info_table[i].length);
505
506 name = fadt_info_table[i].name;
507 flags = fadt_info_table[i].flags;
508
509 /*
510 * Expand the ACPI 1.0 32-bit addresses to the ACPI 2.0 64-bit "X"
511 * generic address structures as necessary. Later code will always use
512 * the 64-bit address structures.
513 *
514 * November 2013:
515 * Now always use the 64-bit address if it is valid (non-zero), in
516 * accordance with the ACPI specification which states that a 64-bit
517 * address supersedes the 32-bit version. This behavior can be
518 * overridden by the acpi_gbl_use32_bit_fadt_addresses flag.
519 *
520 * During 64-bit address construction and verification,
521 * these cases are handled:
522 *
523 * Address32 zero, Address64 [don't care] - Use Address64
524 *
525 * No override: if acpi_gbl_use32_bit_fadt_addresses is FALSE, and:
526 * Address32 non-zero, Address64 zero - Copy/use Address32
527 * Address32 non-zero == Address64 non-zero - Use Address64
528 * Address32 non-zero != Address64 non-zero - Warning, use Address64
529 *
530 * Override: if acpi_gbl_use32_bit_fadt_addresses is TRUE, and:
531 * Address32 non-zero, Address64 zero - Copy/use Address32
532 * Address32 non-zero == Address64 non-zero - Copy/use Address32
533 * Address32 non-zero != Address64 non-zero - Warning, copy/use Address32
534 *
535 * Note: space_id is always I/O for 32-bit legacy address fields
536 */
537 if (address32) {
538 if (address64->address) {
539 if (address64->address != (u64)address32) {
540
541 /* Address mismatch */
542
543 ACPI_BIOS_WARNING((AE_INFO,
544 "32/64X address mismatch in FADT/%s: "
545 "0x%8.8X/0x%8.8X%8.8X, using %u-bit address",
546 name, address32,
547 ACPI_FORMAT_UINT64
548 (address64->address),
549 acpi_gbl_use32_bit_fadt_addresses
550 ? 32 : 64));
551 }
552
553 /*
554 * For each extended field, check for length mismatch
555 * between the legacy length field and the corresponding
556 * 64-bit X length field.
557 * Note: If the legacy length field is > 0xFF bits, ignore
558 * this check. (GPE registers can be larger than the
559 * 64-bit GAS structure can accommodate, 0xFF bits).
560 */
561 if ((ACPI_MUL_8(length) <= ACPI_UINT8_MAX) &&
562 (address64->bit_width !=
563 ACPI_MUL_8(length))) {
564 ACPI_BIOS_WARNING((AE_INFO,
565 "32/64X length mismatch in FADT/%s: %u/%u",
566 name,
567 ACPI_MUL_8(length),
568 address64->
569 bit_width));
570 }
571 }
572
573 /*
574 * Hardware register access code always uses the 64-bit fields.
575 * So if the 64-bit field is zero or is to be overridden,
576 * initialize it with the 32-bit fields.
577 * Note that when the 32-bit address favor is specified, the
578 * 64-bit fields are always re-initialized so that
579 * access_size/bit_width/bit_offset fields can be correctly
580 * configured to the values to trigger a 32-bit compatible
581 * access mode in the hardware register access code.
582 */
583 if (!address64->address
584 || acpi_gbl_use32_bit_fadt_addresses) {
585 acpi_tb_init_generic_address(address64,
586 ACPI_ADR_SPACE_SYSTEM_IO,
587 length,
588 (u64)address32,
589 name, flags);
590 }
591 }
592
593 if (fadt_info_table[i].flags & ACPI_FADT_REQUIRED) {
594 /*
595 * Field is required (Pm1a_event, Pm1a_control).
596 * Both the address and length must be non-zero.
597 */
598 if (!address64->address || !length) {
599 ACPI_BIOS_ERROR((AE_INFO,
600 "Required FADT field %s has zero address and/or length: "
601 "0x%8.8X%8.8X/0x%X",
602 name,
603 ACPI_FORMAT_UINT64(address64->
604 address),
605 length));
606 }
607 } else if (fadt_info_table[i].flags & ACPI_FADT_SEPARATE_LENGTH) {
608 /*
609 * Field is optional (Pm2_control, GPE0, GPE1) AND has its own
610 * length field. If present, both the address and length must
611 * be valid.
612 */
613 if ((address64->address && !length) ||
614 (!address64->address && length)) {
615 ACPI_BIOS_WARNING((AE_INFO,
616 "Optional FADT field %s has valid %s but zero %s: "
617 "0x%8.8X%8.8X/0x%X", name,
618 (length ? "Length" :
619 "Address"),
620 (length ? "Address" :
621 "Length"),
622 ACPI_FORMAT_UINT64
623 (address64->address),
624 length));
625 }
626 }
627 }
628 }
629
630 /*******************************************************************************
631 *
632 * FUNCTION: acpi_tb_setup_fadt_registers
633 *
634 * PARAMETERS: None, uses acpi_gbl_FADT.
635 *
636 * RETURN: None
637 *
638 * DESCRIPTION: Initialize global ACPI PM1 register definitions. Optionally,
639 * force FADT register definitions to their default lengths.
640 *
641 ******************************************************************************/
642
643 static void acpi_tb_setup_fadt_registers(void)
644 {
645 struct acpi_generic_address *target64;
646 struct acpi_generic_address *source64;
647 u8 pm1_register_byte_width;
648 u32 i;
649
650 /*
651 * Optionally check all register lengths against the default values and
652 * update them if they are incorrect.
653 */
654 if (acpi_gbl_use_default_register_widths) {
655 for (i = 0; i < ACPI_FADT_INFO_ENTRIES; i++) {
656 target64 =
657 ACPI_ADD_PTR(struct acpi_generic_address,
658 &acpi_gbl_FADT,
659 fadt_info_table[i].address64);
660
661 /*
662 * If a valid register (Address != 0) and the (default_length > 0)
663 * (Not a GPE register), then check the width against the default.
664 */
665 if ((target64->address) &&
666 (fadt_info_table[i].default_length > 0) &&
667 (fadt_info_table[i].default_length !=
668 target64->bit_width)) {
669 ACPI_BIOS_WARNING((AE_INFO,
670 "Invalid length for FADT/%s: %u, using default %u",
671 fadt_info_table[i].name,
672 target64->bit_width,
673 fadt_info_table[i].
674 default_length));
675
676 /* Incorrect size, set width to the default */
677
678 target64->bit_width =
679 fadt_info_table[i].default_length;
680 }
681 }
682 }
683
684 /*
685 * Get the length of the individual PM1 registers (enable and status).
686 * Each register is defined to be (event block length / 2). Extra divide
687 * by 8 converts bits to bytes.
688 */
689 pm1_register_byte_width = (u8)
690 ACPI_DIV_16(acpi_gbl_FADT.xpm1a_event_block.bit_width);
691
692 /*
693 * Calculate separate GAS structs for the PM1x (A/B) Status and Enable
694 * registers. These addresses do not appear (directly) in the FADT, so it
695 * is useful to pre-calculate them from the PM1 Event Block definitions.
696 *
697 * The PM event blocks are split into two register blocks, first is the
698 * PM Status Register block, followed immediately by the PM Enable
699 * Register block. Each is of length (pm1_event_length/2)
700 *
701 * Note: The PM1A event block is required by the ACPI specification.
702 * However, the PM1B event block is optional and is rarely, if ever,
703 * used.
704 */
705
706 for (i = 0; i < ACPI_FADT_PM_INFO_ENTRIES; i++) {
707 source64 =
708 ACPI_ADD_PTR(struct acpi_generic_address, &acpi_gbl_FADT,
709 fadt_pm_info_table[i].source);
710
711 if (source64->address) {
712 acpi_tb_init_generic_address(fadt_pm_info_table[i].
713 target, source64->space_id,
714 pm1_register_byte_width,
715 source64->address +
716 (fadt_pm_info_table[i].
717 register_num *
718 pm1_register_byte_width),
719 "PmRegisters", 0);
720 }
721 }
722 }