]> git.proxmox.com Git - mirror_ubuntu-zesty-kernel.git/blob - drivers/acpi/acpica/tbfadt.c
ACPICA: Add option to favor 32-bit FADT addresses.
[mirror_ubuntu-zesty-kernel.git] / drivers / acpi / acpica / tbfadt.c
1 /******************************************************************************
2 *
3 * Module Name: tbfadt - FADT table utilities
4 *
5 *****************************************************************************/
6
7 /*
8 * Copyright (C) 2000 - 2013, Intel Corp.
9 * All rights reserved.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions, and the following disclaimer,
16 * without modification.
17 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18 * substantially similar to the "NO WARRANTY" disclaimer below
19 * ("Disclaimer") and any redistribution must be conditioned upon
20 * including a substantially similar Disclaimer requirement for further
21 * binary redistribution.
22 * 3. Neither the names of the above-listed copyright holders nor the names
23 * of any contributors may be used to endorse or promote products derived
24 * from this software without specific prior written permission.
25 *
26 * Alternatively, this software may be distributed under the terms of the
27 * GNU General Public License ("GPL") version 2 as published by the Free
28 * Software Foundation.
29 *
30 * NO WARRANTY
31 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
34 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41 * POSSIBILITY OF SUCH DAMAGES.
42 */
43
44 #include <acpi/acpi.h>
45 #include "accommon.h"
46 #include "actables.h"
47
48 #define _COMPONENT ACPI_TABLES
49 ACPI_MODULE_NAME("tbfadt")
50
51 /* Local prototypes */
52 static void
53 acpi_tb_init_generic_address(struct acpi_generic_address *generic_address,
54 u8 space_id,
55 u8 byte_width, u64 address, char *register_name);
56
57 static void acpi_tb_convert_fadt(void);
58
59 static void acpi_tb_setup_fadt_registers(void);
60
61 static u64
62 acpi_tb_select_address(char *register_name, u32 address32, u64 address64);
63
64 /* Table for conversion of FADT to common internal format and FADT validation */
65
66 typedef struct acpi_fadt_info {
67 char *name;
68 u16 address64;
69 u16 address32;
70 u16 length;
71 u8 default_length;
72 u8 type;
73
74 } acpi_fadt_info;
75
76 #define ACPI_FADT_OPTIONAL 0
77 #define ACPI_FADT_REQUIRED 1
78 #define ACPI_FADT_SEPARATE_LENGTH 2
79
80 static struct acpi_fadt_info fadt_info_table[] = {
81 {"Pm1aEventBlock",
82 ACPI_FADT_OFFSET(xpm1a_event_block),
83 ACPI_FADT_OFFSET(pm1a_event_block),
84 ACPI_FADT_OFFSET(pm1_event_length),
85 ACPI_PM1_REGISTER_WIDTH * 2, /* Enable + Status register */
86 ACPI_FADT_REQUIRED},
87
88 {"Pm1bEventBlock",
89 ACPI_FADT_OFFSET(xpm1b_event_block),
90 ACPI_FADT_OFFSET(pm1b_event_block),
91 ACPI_FADT_OFFSET(pm1_event_length),
92 ACPI_PM1_REGISTER_WIDTH * 2, /* Enable + Status register */
93 ACPI_FADT_OPTIONAL},
94
95 {"Pm1aControlBlock",
96 ACPI_FADT_OFFSET(xpm1a_control_block),
97 ACPI_FADT_OFFSET(pm1a_control_block),
98 ACPI_FADT_OFFSET(pm1_control_length),
99 ACPI_PM1_REGISTER_WIDTH,
100 ACPI_FADT_REQUIRED},
101
102 {"Pm1bControlBlock",
103 ACPI_FADT_OFFSET(xpm1b_control_block),
104 ACPI_FADT_OFFSET(pm1b_control_block),
105 ACPI_FADT_OFFSET(pm1_control_length),
106 ACPI_PM1_REGISTER_WIDTH,
107 ACPI_FADT_OPTIONAL},
108
109 {"Pm2ControlBlock",
110 ACPI_FADT_OFFSET(xpm2_control_block),
111 ACPI_FADT_OFFSET(pm2_control_block),
112 ACPI_FADT_OFFSET(pm2_control_length),
113 ACPI_PM2_REGISTER_WIDTH,
114 ACPI_FADT_SEPARATE_LENGTH},
115
116 {"PmTimerBlock",
117 ACPI_FADT_OFFSET(xpm_timer_block),
118 ACPI_FADT_OFFSET(pm_timer_block),
119 ACPI_FADT_OFFSET(pm_timer_length),
120 ACPI_PM_TIMER_WIDTH,
121 ACPI_FADT_SEPARATE_LENGTH}, /* ACPI 5.0A: Timer is optional */
122
123 {"Gpe0Block",
124 ACPI_FADT_OFFSET(xgpe0_block),
125 ACPI_FADT_OFFSET(gpe0_block),
126 ACPI_FADT_OFFSET(gpe0_block_length),
127 0,
128 ACPI_FADT_SEPARATE_LENGTH},
129
130 {"Gpe1Block",
131 ACPI_FADT_OFFSET(xgpe1_block),
132 ACPI_FADT_OFFSET(gpe1_block),
133 ACPI_FADT_OFFSET(gpe1_block_length),
134 0,
135 ACPI_FADT_SEPARATE_LENGTH}
136 };
137
138 #define ACPI_FADT_INFO_ENTRIES \
139 (sizeof (fadt_info_table) / sizeof (struct acpi_fadt_info))
140
141 /* Table used to split Event Blocks into separate status/enable registers */
142
143 typedef struct acpi_fadt_pm_info {
144 struct acpi_generic_address *target;
145 u16 source;
146 u8 register_num;
147
148 } acpi_fadt_pm_info;
149
150 static struct acpi_fadt_pm_info fadt_pm_info_table[] = {
151 {&acpi_gbl_xpm1a_status,
152 ACPI_FADT_OFFSET(xpm1a_event_block),
153 0},
154
155 {&acpi_gbl_xpm1a_enable,
156 ACPI_FADT_OFFSET(xpm1a_event_block),
157 1},
158
159 {&acpi_gbl_xpm1b_status,
160 ACPI_FADT_OFFSET(xpm1b_event_block),
161 0},
162
163 {&acpi_gbl_xpm1b_enable,
164 ACPI_FADT_OFFSET(xpm1b_event_block),
165 1}
166 };
167
168 #define ACPI_FADT_PM_INFO_ENTRIES \
169 (sizeof (fadt_pm_info_table) / sizeof (struct acpi_fadt_pm_info))
170
171 /*******************************************************************************
172 *
173 * FUNCTION: acpi_tb_init_generic_address
174 *
175 * PARAMETERS: generic_address - GAS struct to be initialized
176 * space_id - ACPI Space ID for this register
177 * byte_width - Width of this register
178 * address - Address of the register
179 * register_name - ASCII name of the ACPI register
180 *
181 * RETURN: None
182 *
183 * DESCRIPTION: Initialize a Generic Address Structure (GAS)
184 * See the ACPI specification for a full description and
185 * definition of this structure.
186 *
187 ******************************************************************************/
188
189 static void
190 acpi_tb_init_generic_address(struct acpi_generic_address *generic_address,
191 u8 space_id,
192 u8 byte_width, u64 address, char *register_name)
193 {
194 u8 bit_width;
195
196 /* Bit width field in the GAS is only one byte long, 255 max */
197
198 bit_width = (u8)(byte_width * 8);
199
200 if (byte_width > 31) { /* (31*8)=248 */
201 ACPI_ERROR((AE_INFO,
202 "%s - 32-bit FADT register is too long (%u bytes, %u bits) "
203 "to convert to GAS struct - 255 bits max, truncating",
204 register_name, byte_width, (byte_width * 8)));
205
206 bit_width = 255;
207 }
208
209 /*
210 * The 64-bit Address field is non-aligned in the byte packed
211 * GAS struct.
212 */
213 ACPI_MOVE_64_TO_64(&generic_address->address, &address);
214
215 /* All other fields are byte-wide */
216
217 generic_address->space_id = space_id;
218 generic_address->bit_width = bit_width;
219 generic_address->bit_offset = 0;
220 generic_address->access_width = 0; /* Access width ANY */
221 }
222
223 /*******************************************************************************
224 *
225 * FUNCTION: acpi_tb_select_address
226 *
227 * PARAMETERS: register_name - ASCII name of the ACPI register
228 * address32 - 32-bit address of the register
229 * address64 - 64-bit address of the register
230 *
231 * RETURN: The resolved 64-bit address
232 *
233 * DESCRIPTION: Select between 32-bit and 64-bit versions of addresses within
234 * the FADT. Used for the FACS and DSDT addresses.
235 *
236 * NOTES:
237 *
238 * Check for FACS and DSDT address mismatches. An address mismatch between
239 * the 32-bit and 64-bit address fields (FIRMWARE_CTRL/X_FIRMWARE_CTRL and
240 * DSDT/X_DSDT) could be a corrupted address field or it might indicate
241 * the presence of two FACS or two DSDT tables.
242 *
243 * November 2013:
244 * By default, as per the ACPICA specification, a valid 64-bit address is
245 * used regardless of the value of the 32-bit address. However, this
246 * behavior can be overridden via the acpi_gbl_use32_bit_fadt_addresses flag.
247 *
248 ******************************************************************************/
249
250 static u64
251 acpi_tb_select_address(char *register_name, u32 address32, u64 address64)
252 {
253
254 if (!address64) {
255
256 /* 64-bit address is zero, use 32-bit address */
257
258 return ((u64)address32);
259 }
260
261 if (address32 && (address64 != (u64)address32)) {
262
263 /* Address mismatch between 32-bit and 64-bit versions */
264
265 ACPI_BIOS_WARNING((AE_INFO,
266 "32/64X %s address mismatch in FADT: "
267 "0x%8.8X/0x%8.8X%8.8X, using %u-bit address",
268 register_name, address32,
269 ACPI_FORMAT_UINT64(address64),
270 acpi_gbl_use32_bit_fadt_addresses ? 32 :
271 64));
272
273 /* 32-bit address override */
274
275 if (acpi_gbl_use32_bit_fadt_addresses) {
276 return ((u64)address32);
277 }
278 }
279
280 /* Default is to use the 64-bit address */
281
282 return (address64);
283 }
284
285 /*******************************************************************************
286 *
287 * FUNCTION: acpi_tb_parse_fadt
288 *
289 * PARAMETERS: table_index - Index for the FADT
290 *
291 * RETURN: None
292 *
293 * DESCRIPTION: Initialize the FADT, DSDT and FACS tables
294 * (FADT contains the addresses of the DSDT and FACS)
295 *
296 ******************************************************************************/
297
298 void acpi_tb_parse_fadt(u32 table_index)
299 {
300 u32 length;
301 struct acpi_table_header *table;
302
303 /*
304 * The FADT has multiple versions with different lengths,
305 * and it contains pointers to both the DSDT and FACS tables.
306 *
307 * Get a local copy of the FADT and convert it to a common format
308 * Map entire FADT, assumed to be smaller than one page.
309 */
310 length = acpi_gbl_root_table_list.tables[table_index].length;
311
312 table =
313 acpi_os_map_memory(acpi_gbl_root_table_list.tables[table_index].
314 address, length);
315 if (!table) {
316 return;
317 }
318
319 /*
320 * Validate the FADT checksum before we copy the table. Ignore
321 * checksum error as we want to try to get the DSDT and FACS.
322 */
323 (void)acpi_tb_verify_checksum(table, length);
324
325 /* Create a local copy of the FADT in common ACPI 2.0+ format */
326
327 acpi_tb_create_local_fadt(table, length);
328
329 /* All done with the real FADT, unmap it */
330
331 acpi_os_unmap_memory(table, length);
332
333 /* Obtain the DSDT and FACS tables via their addresses within the FADT */
334
335 acpi_tb_install_table((acpi_physical_address) acpi_gbl_FADT.Xdsdt,
336 ACPI_SIG_DSDT, ACPI_TABLE_INDEX_DSDT);
337
338 /* If Hardware Reduced flag is set, there is no FACS */
339
340 if (!acpi_gbl_reduced_hardware) {
341 acpi_tb_install_table((acpi_physical_address) acpi_gbl_FADT.
342 Xfacs, ACPI_SIG_FACS,
343 ACPI_TABLE_INDEX_FACS);
344 }
345 }
346
347 /*******************************************************************************
348 *
349 * FUNCTION: acpi_tb_create_local_fadt
350 *
351 * PARAMETERS: table - Pointer to BIOS FADT
352 * length - Length of the table
353 *
354 * RETURN: None
355 *
356 * DESCRIPTION: Get a local copy of the FADT and convert it to a common format.
357 * Performs validation on some important FADT fields.
358 *
359 * NOTE: We create a local copy of the FADT regardless of the version.
360 *
361 ******************************************************************************/
362
363 void acpi_tb_create_local_fadt(struct acpi_table_header *table, u32 length)
364 {
365 /*
366 * Check if the FADT is larger than the largest table that we expect
367 * (the ACPI 5.0 version). If so, truncate the table, and issue
368 * a warning.
369 */
370 if (length > sizeof(struct acpi_table_fadt)) {
371 ACPI_BIOS_WARNING((AE_INFO,
372 "FADT (revision %u) is longer than ACPI 5.0 version, "
373 "truncating length %u to %u",
374 table->revision, length,
375 (u32)sizeof(struct acpi_table_fadt)));
376 }
377
378 /* Clear the entire local FADT */
379
380 ACPI_MEMSET(&acpi_gbl_FADT, 0, sizeof(struct acpi_table_fadt));
381
382 /* Copy the original FADT, up to sizeof (struct acpi_table_fadt) */
383
384 ACPI_MEMCPY(&acpi_gbl_FADT, table,
385 ACPI_MIN(length, sizeof(struct acpi_table_fadt)));
386
387 /* Take a copy of the Hardware Reduced flag */
388
389 acpi_gbl_reduced_hardware = FALSE;
390 if (acpi_gbl_FADT.flags & ACPI_FADT_HW_REDUCED) {
391 acpi_gbl_reduced_hardware = TRUE;
392 }
393
394 /* Convert the local copy of the FADT to the common internal format */
395
396 acpi_tb_convert_fadt();
397
398 /* Initialize the global ACPI register structures */
399
400 acpi_tb_setup_fadt_registers();
401 }
402
403 /*******************************************************************************
404 *
405 * FUNCTION: acpi_tb_convert_fadt
406 *
407 * PARAMETERS: none - acpi_gbl_FADT is used.
408 *
409 * RETURN: None
410 *
411 * DESCRIPTION: Converts all versions of the FADT to a common internal format.
412 * Expand 32-bit addresses to 64-bit as necessary. Also validate
413 * important fields within the FADT.
414 *
415 * NOTE: acpi_gbl_FADT must be of size (struct acpi_table_fadt), and must
416 * contain a copy of the actual BIOS-provided FADT.
417 *
418 * Notes on 64-bit register addresses:
419 *
420 * After this FADT conversion, later ACPICA code will only use the 64-bit "X"
421 * fields of the FADT for all ACPI register addresses.
422 *
423 * The 64-bit X fields are optional extensions to the original 32-bit FADT
424 * V1.0 fields. Even if they are present in the FADT, they are optional and
425 * are unused if the BIOS sets them to zero. Therefore, we must copy/expand
426 * 32-bit V1.0 fields to the 64-bit X fields if the the 64-bit X field is
427 * originally zero.
428 *
429 * For ACPI 1.0 FADTs (that contain no 64-bit addresses), all 32-bit address
430 * fields are expanded to the corresponding 64-bit X fields in the internal
431 * common FADT.
432 *
433 * For ACPI 2.0+ FADTs, all valid (non-zero) 32-bit address fields are expanded
434 * to the corresponding 64-bit X fields, if the 64-bit field is originally
435 * zero. Adhering to the ACPI specification, we completely ignore the 32-bit
436 * field if the 64-bit field is valid, regardless of whether the host OS is
437 * 32-bit or 64-bit.
438 *
439 * Possible additional checks:
440 * (acpi_gbl_FADT.pm1_event_length >= 4)
441 * (acpi_gbl_FADT.pm1_control_length >= 2)
442 * (acpi_gbl_FADT.pm_timer_length >= 4)
443 * Gpe block lengths must be multiple of 2
444 *
445 ******************************************************************************/
446
447 static void acpi_tb_convert_fadt(void)
448 {
449 char *name;
450 struct acpi_generic_address *address64;
451 u32 address32;
452 u8 length;
453 u32 i;
454
455 /*
456 * For ACPI 1.0 FADTs (revision 1 or 2), ensure that reserved fields which
457 * should be zero are indeed zero. This will workaround BIOSs that
458 * inadvertently place values in these fields.
459 *
460 * The ACPI 1.0 reserved fields that will be zeroed are the bytes located
461 * at offset 45, 55, 95, and the word located at offset 109, 110.
462 *
463 * Note: The FADT revision value is unreliable. Only the length can be
464 * trusted.
465 */
466 if (acpi_gbl_FADT.header.length <= ACPI_FADT_V2_SIZE) {
467 acpi_gbl_FADT.preferred_profile = 0;
468 acpi_gbl_FADT.pstate_control = 0;
469 acpi_gbl_FADT.cst_control = 0;
470 acpi_gbl_FADT.boot_flags = 0;
471 }
472
473 /*
474 * Now we can update the local FADT length to the length of the
475 * current FADT version as defined by the ACPI specification.
476 * Thus, we will have a common FADT internally.
477 */
478 acpi_gbl_FADT.header.length = sizeof(struct acpi_table_fadt);
479
480 /*
481 * Expand the 32-bit FACS and DSDT addresses to 64-bit as necessary.
482 * Later ACPICA code will always use the X 64-bit field.
483 */
484 acpi_gbl_FADT.Xfacs = acpi_tb_select_address("FACS",
485 acpi_gbl_FADT.facs,
486 acpi_gbl_FADT.Xfacs);
487
488 acpi_gbl_FADT.Xdsdt = acpi_tb_select_address("DSDT",
489 acpi_gbl_FADT.dsdt,
490 acpi_gbl_FADT.Xdsdt);
491
492 /* If Hardware Reduced flag is set, we are all done */
493
494 if (acpi_gbl_reduced_hardware) {
495 return;
496 }
497
498 /* Examine all of the 64-bit extended address fields (X fields) */
499
500 for (i = 0; i < ACPI_FADT_INFO_ENTRIES; i++) {
501 /*
502 * Get the 32-bit and 64-bit addresses, as well as the register
503 * length and register name.
504 */
505 address32 = *ACPI_ADD_PTR(u32,
506 &acpi_gbl_FADT,
507 fadt_info_table[i].address32);
508
509 address64 = ACPI_ADD_PTR(struct acpi_generic_address,
510 &acpi_gbl_FADT,
511 fadt_info_table[i].address64);
512
513 length = *ACPI_ADD_PTR(u8,
514 &acpi_gbl_FADT,
515 fadt_info_table[i].length);
516
517 name = fadt_info_table[i].name;
518
519 /*
520 * Expand the ACPI 1.0 32-bit addresses to the ACPI 2.0 64-bit "X"
521 * generic address structures as necessary. Later code will always use
522 * the 64-bit address structures.
523 *
524 * November 2013:
525 * Now always use the 64-bit address if it is valid (non-zero), in
526 * accordance with the ACPI specification which states that a 64-bit
527 * address supersedes the 32-bit version. This behavior can be
528 * overridden by the acpi_gbl_use32_bit_fadt_addresses flag.
529 *
530 * During 64-bit address construction and verification,
531 * these cases are handled:
532 *
533 * Address32 zero, Address64 [don't care] - Use Address64
534 *
535 * Address32 non-zero, Address64 zero - Copy/use Address32
536 * Address32 non-zero == Address64 non-zero - Use Address64
537 * Address32 non-zero != Address64 non-zero - Warning, use Address64
538 *
539 * Override: if acpi_gbl_use32_bit_fadt_addresses is TRUE, and:
540 * Address32 non-zero != Address64 non-zero - Warning, copy/use Address32
541 *
542 * Note: space_id is always I/O for 32-bit legacy address fields
543 */
544 if (address32) {
545 if (!address64->address) {
546
547 /* 64-bit address is zero, use 32-bit address */
548
549 acpi_tb_init_generic_address(address64,
550 ACPI_ADR_SPACE_SYSTEM_IO,
551 *ACPI_ADD_PTR(u8,
552 &acpi_gbl_FADT,
553 fadt_info_table
554 [i].
555 length),
556 (u64)address32,
557 name);
558 } else if (address64->address != (u64)address32) {
559
560 /* Address mismatch */
561
562 ACPI_BIOS_WARNING((AE_INFO,
563 "32/64X address mismatch in FADT/%s: "
564 "0x%8.8X/0x%8.8X%8.8X, using %u-bit address",
565 name, address32,
566 ACPI_FORMAT_UINT64
567 (address64->address),
568 acpi_gbl_use32_bit_fadt_addresses
569 ? 32 : 64));
570
571 if (acpi_gbl_use32_bit_fadt_addresses) {
572
573 /* 32-bit address override */
574
575 acpi_tb_init_generic_address(address64,
576 ACPI_ADR_SPACE_SYSTEM_IO,
577 *ACPI_ADD_PTR
578 (u8,
579 &acpi_gbl_FADT,
580 fadt_info_table
581 [i].
582 length),
583 (u64)
584 address32,
585 name);
586 }
587 }
588 }
589
590 /*
591 * For each extended field, check for length mismatch between the
592 * legacy length field and the corresponding 64-bit X length field.
593 * Note: If the legacy length field is > 0xFF bits, ignore this
594 * check. (GPE registers can be larger than the 64-bit GAS structure
595 * can accomodate, 0xFF bits).
596 */
597 if (address64->address &&
598 (ACPI_MUL_8(length) <= ACPI_UINT8_MAX) &&
599 (address64->bit_width != ACPI_MUL_8(length))) {
600 ACPI_BIOS_WARNING((AE_INFO,
601 "32/64X length mismatch in FADT/%s: %u/%u",
602 name, ACPI_MUL_8(length),
603 address64->bit_width));
604 }
605
606 if (fadt_info_table[i].type & ACPI_FADT_REQUIRED) {
607 /*
608 * Field is required (Pm1a_event, Pm1a_control).
609 * Both the address and length must be non-zero.
610 */
611 if (!address64->address || !length) {
612 ACPI_BIOS_ERROR((AE_INFO,
613 "Required FADT field %s has zero address and/or length: "
614 "0x%8.8X%8.8X/0x%X",
615 name,
616 ACPI_FORMAT_UINT64(address64->
617 address),
618 length));
619 }
620 } else if (fadt_info_table[i].type & ACPI_FADT_SEPARATE_LENGTH) {
621 /*
622 * Field is optional (Pm2_control, GPE0, GPE1) AND has its own
623 * length field. If present, both the address and length must
624 * be valid.
625 */
626 if ((address64->address && !length) ||
627 (!address64->address && length)) {
628 ACPI_BIOS_WARNING((AE_INFO,
629 "Optional FADT field %s has zero address or length: "
630 "0x%8.8X%8.8X/0x%X",
631 name,
632 ACPI_FORMAT_UINT64
633 (address64->address),
634 length));
635 }
636 }
637 }
638 }
639
640 /*******************************************************************************
641 *
642 * FUNCTION: acpi_tb_setup_fadt_registers
643 *
644 * PARAMETERS: None, uses acpi_gbl_FADT.
645 *
646 * RETURN: None
647 *
648 * DESCRIPTION: Initialize global ACPI PM1 register definitions. Optionally,
649 * force FADT register definitions to their default lengths.
650 *
651 ******************************************************************************/
652
653 static void acpi_tb_setup_fadt_registers(void)
654 {
655 struct acpi_generic_address *target64;
656 struct acpi_generic_address *source64;
657 u8 pm1_register_byte_width;
658 u32 i;
659
660 /*
661 * Optionally check all register lengths against the default values and
662 * update them if they are incorrect.
663 */
664 if (acpi_gbl_use_default_register_widths) {
665 for (i = 0; i < ACPI_FADT_INFO_ENTRIES; i++) {
666 target64 =
667 ACPI_ADD_PTR(struct acpi_generic_address,
668 &acpi_gbl_FADT,
669 fadt_info_table[i].address64);
670
671 /*
672 * If a valid register (Address != 0) and the (default_length > 0)
673 * (Not a GPE register), then check the width against the default.
674 */
675 if ((target64->address) &&
676 (fadt_info_table[i].default_length > 0) &&
677 (fadt_info_table[i].default_length !=
678 target64->bit_width)) {
679 ACPI_BIOS_WARNING((AE_INFO,
680 "Invalid length for FADT/%s: %u, using default %u",
681 fadt_info_table[i].name,
682 target64->bit_width,
683 fadt_info_table[i].
684 default_length));
685
686 /* Incorrect size, set width to the default */
687
688 target64->bit_width =
689 fadt_info_table[i].default_length;
690 }
691 }
692 }
693
694 /*
695 * Get the length of the individual PM1 registers (enable and status).
696 * Each register is defined to be (event block length / 2). Extra divide
697 * by 8 converts bits to bytes.
698 */
699 pm1_register_byte_width = (u8)
700 ACPI_DIV_16(acpi_gbl_FADT.xpm1a_event_block.bit_width);
701
702 /*
703 * Calculate separate GAS structs for the PM1x (A/B) Status and Enable
704 * registers. These addresses do not appear (directly) in the FADT, so it
705 * is useful to pre-calculate them from the PM1 Event Block definitions.
706 *
707 * The PM event blocks are split into two register blocks, first is the
708 * PM Status Register block, followed immediately by the PM Enable
709 * Register block. Each is of length (pm1_event_length/2)
710 *
711 * Note: The PM1A event block is required by the ACPI specification.
712 * However, the PM1B event block is optional and is rarely, if ever,
713 * used.
714 */
715
716 for (i = 0; i < ACPI_FADT_PM_INFO_ENTRIES; i++) {
717 source64 =
718 ACPI_ADD_PTR(struct acpi_generic_address, &acpi_gbl_FADT,
719 fadt_pm_info_table[i].source);
720
721 if (source64->address) {
722 acpi_tb_init_generic_address(fadt_pm_info_table[i].
723 target, source64->space_id,
724 pm1_register_byte_width,
725 source64->address +
726 (fadt_pm_info_table[i].
727 register_num *
728 pm1_register_byte_width),
729 "PmRegisters");
730 }
731 }
732 }