GNU Linux-libre 4.14.290-gnu1
[releases.git] / drivers / acpi / acpica / tbfadt.c
1 /******************************************************************************
2  *
3  * Module Name: tbfadt   - FADT table utilities
4  *
5  *****************************************************************************/
6
7 /*
8  * Copyright (C) 2000 - 2017, 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,
56                              u64 address, const char *register_name, u8 flags);
57
58 static void acpi_tb_convert_fadt(void);
59
60 static void acpi_tb_setup_fadt_registers(void);
61
62 static u64
63 acpi_tb_select_address(char *register_name, u32 address32, u64 address64);
64
65 /* Table for conversion of FADT to common internal format and FADT validation */
66
67 typedef struct acpi_fadt_info {
68         const char *name;
69         u16 address64;
70         u16 address32;
71         u16 length;
72         u8 default_length;
73         u8 flags;
74
75 } acpi_fadt_info;
76
77 #define ACPI_FADT_OPTIONAL          0
78 #define ACPI_FADT_REQUIRED          1
79 #define ACPI_FADT_SEPARATE_LENGTH   2
80 #define ACPI_FADT_GPE_REGISTER      4
81
82 static struct acpi_fadt_info fadt_info_table[] = {
83         {"Pm1aEventBlock",
84          ACPI_FADT_OFFSET(xpm1a_event_block),
85          ACPI_FADT_OFFSET(pm1a_event_block),
86          ACPI_FADT_OFFSET(pm1_event_length),
87          ACPI_PM1_REGISTER_WIDTH * 2,   /* Enable + Status register */
88          ACPI_FADT_REQUIRED},
89
90         {"Pm1bEventBlock",
91          ACPI_FADT_OFFSET(xpm1b_event_block),
92          ACPI_FADT_OFFSET(pm1b_event_block),
93          ACPI_FADT_OFFSET(pm1_event_length),
94          ACPI_PM1_REGISTER_WIDTH * 2,   /* Enable + Status register */
95          ACPI_FADT_OPTIONAL},
96
97         {"Pm1aControlBlock",
98          ACPI_FADT_OFFSET(xpm1a_control_block),
99          ACPI_FADT_OFFSET(pm1a_control_block),
100          ACPI_FADT_OFFSET(pm1_control_length),
101          ACPI_PM1_REGISTER_WIDTH,
102          ACPI_FADT_REQUIRED},
103
104         {"Pm1bControlBlock",
105          ACPI_FADT_OFFSET(xpm1b_control_block),
106          ACPI_FADT_OFFSET(pm1b_control_block),
107          ACPI_FADT_OFFSET(pm1_control_length),
108          ACPI_PM1_REGISTER_WIDTH,
109          ACPI_FADT_OPTIONAL},
110
111         {"Pm2ControlBlock",
112          ACPI_FADT_OFFSET(xpm2_control_block),
113          ACPI_FADT_OFFSET(pm2_control_block),
114          ACPI_FADT_OFFSET(pm2_control_length),
115          ACPI_PM2_REGISTER_WIDTH,
116          ACPI_FADT_SEPARATE_LENGTH},
117
118         {"PmTimerBlock",
119          ACPI_FADT_OFFSET(xpm_timer_block),
120          ACPI_FADT_OFFSET(pm_timer_block),
121          ACPI_FADT_OFFSET(pm_timer_length),
122          ACPI_PM_TIMER_WIDTH,
123          ACPI_FADT_SEPARATE_LENGTH},    /* ACPI 5.0A: Timer is optional */
124
125         {"Gpe0Block",
126          ACPI_FADT_OFFSET(xgpe0_block),
127          ACPI_FADT_OFFSET(gpe0_block),
128          ACPI_FADT_OFFSET(gpe0_block_length),
129          0,
130          ACPI_FADT_SEPARATE_LENGTH | ACPI_FADT_GPE_REGISTER},
131
132         {"Gpe1Block",
133          ACPI_FADT_OFFSET(xgpe1_block),
134          ACPI_FADT_OFFSET(gpe1_block),
135          ACPI_FADT_OFFSET(gpe1_block_length),
136          0,
137          ACPI_FADT_SEPARATE_LENGTH | ACPI_FADT_GPE_REGISTER}
138 };
139
140 #define ACPI_FADT_INFO_ENTRIES \
141                         (sizeof (fadt_info_table) / sizeof (struct acpi_fadt_info))
142
143 /* Table used to split Event Blocks into separate status/enable registers */
144
145 typedef struct acpi_fadt_pm_info {
146         struct acpi_generic_address *target;
147         u16 source;
148         u8 register_num;
149
150 } acpi_fadt_pm_info;
151
152 static struct acpi_fadt_pm_info fadt_pm_info_table[] = {
153         {&acpi_gbl_xpm1a_status,
154          ACPI_FADT_OFFSET(xpm1a_event_block),
155          0},
156
157         {&acpi_gbl_xpm1a_enable,
158          ACPI_FADT_OFFSET(xpm1a_event_block),
159          1},
160
161         {&acpi_gbl_xpm1b_status,
162          ACPI_FADT_OFFSET(xpm1b_event_block),
163          0},
164
165         {&acpi_gbl_xpm1b_enable,
166          ACPI_FADT_OFFSET(xpm1b_event_block),
167          1}
168 };
169
170 #define ACPI_FADT_PM_INFO_ENTRIES \
171                         (sizeof (fadt_pm_info_table) / sizeof (struct acpi_fadt_pm_info))
172
173 /*******************************************************************************
174  *
175  * FUNCTION:    acpi_tb_init_generic_address
176  *
177  * PARAMETERS:  generic_address     - GAS struct to be initialized
178  *              space_id            - ACPI Space ID for this register
179  *              byte_width          - Width of this register
180  *              address             - Address of the register
181  *              register_name       - ASCII name of the ACPI register
182  *
183  * RETURN:      None
184  *
185  * DESCRIPTION: Initialize a Generic Address Structure (GAS)
186  *              See the ACPI specification for a full description and
187  *              definition of this structure.
188  *
189  ******************************************************************************/
190
191 static void
192 acpi_tb_init_generic_address(struct acpi_generic_address *generic_address,
193                              u8 space_id,
194                              u8 byte_width,
195                              u64 address, const char *register_name, u8 flags)
196 {
197         u8 bit_width;
198
199         /*
200          * Bit width field in the GAS is only one byte long, 255 max.
201          * Check for bit_width overflow in GAS.
202          */
203         bit_width = (u8)(byte_width * 8);
204         if (byte_width > 31) {  /* (31*8)=248, (32*8)=256 */
205                 /*
206                  * No error for GPE blocks, because we do not use the bit_width
207                  * for GPEs, the legacy length (byte_width) is used instead to
208                  * allow for a large number of GPEs.
209                  */
210                 if (!(flags & ACPI_FADT_GPE_REGISTER)) {
211                         ACPI_ERROR((AE_INFO,
212                                     "%s - 32-bit FADT register is too long (%u bytes, %u bits) "
213                                     "to convert to GAS struct - 255 bits max, truncating",
214                                     register_name, byte_width,
215                                     (byte_width * 8)));
216                 }
217
218                 bit_width = 255;
219         }
220
221         /*
222          * The 64-bit Address field is non-aligned in the byte packed
223          * GAS struct.
224          */
225         ACPI_MOVE_64_TO_64(&generic_address->address, &address);
226
227         /* All other fields are byte-wide */
228
229         generic_address->space_id = space_id;
230         generic_address->bit_width = bit_width;
231         generic_address->bit_offset = 0;
232         generic_address->access_width = 0;      /* Access width ANY */
233 }
234
235 /*******************************************************************************
236  *
237  * FUNCTION:    acpi_tb_select_address
238  *
239  * PARAMETERS:  register_name       - ASCII name of the ACPI register
240  *              address32           - 32-bit address of the register
241  *              address64           - 64-bit address of the register
242  *
243  * RETURN:      The resolved 64-bit address
244  *
245  * DESCRIPTION: Select between 32-bit and 64-bit versions of addresses within
246  *              the FADT. Used for the FACS and DSDT addresses.
247  *
248  * NOTES:
249  *
250  * Check for FACS and DSDT address mismatches. An address mismatch between
251  * the 32-bit and 64-bit address fields (FIRMWARE_CTRL/X_FIRMWARE_CTRL and
252  * DSDT/X_DSDT) could be a corrupted address field or it might indicate
253  * the presence of two FACS or two DSDT tables.
254  *
255  * November 2013:
256  * By default, as per the ACPICA specification, a valid 64-bit address is
257  * used regardless of the value of the 32-bit address. However, this
258  * behavior can be overridden via the acpi_gbl_use32_bit_fadt_addresses flag.
259  *
260  ******************************************************************************/
261
262 static u64
263 acpi_tb_select_address(char *register_name, u32 address32, u64 address64)
264 {
265
266         if (!address64) {
267
268                 /* 64-bit address is zero, use 32-bit address */
269
270                 return ((u64)address32);
271         }
272
273         if (address32 && (address64 != (u64)address32)) {
274
275                 /* Address mismatch between 32-bit and 64-bit versions */
276
277                 ACPI_BIOS_WARNING((AE_INFO,
278                                    "32/64X %s address mismatch in FADT: "
279                                    "0x%8.8X/0x%8.8X%8.8X, using %u-bit address",
280                                    register_name, address32,
281                                    ACPI_FORMAT_UINT64(address64),
282                                    acpi_gbl_use32_bit_fadt_addresses ? 32 :
283                                    64));
284
285                 /* 32-bit address override */
286
287                 if (acpi_gbl_use32_bit_fadt_addresses) {
288                         return ((u64)address32);
289                 }
290         }
291
292         /* Default is to use the 64-bit address */
293
294         return (address64);
295 }
296
297 /*******************************************************************************
298  *
299  * FUNCTION:    acpi_tb_parse_fadt
300  *
301  * PARAMETERS:  None
302  *
303  * RETURN:      None
304  *
305  * DESCRIPTION: Initialize the FADT, DSDT and FACS tables
306  *              (FADT contains the addresses of the DSDT and FACS)
307  *
308  ******************************************************************************/
309
310 void acpi_tb_parse_fadt(void)
311 {
312         u32 length;
313         struct acpi_table_header *table;
314         struct acpi_table_desc *fadt_desc;
315         acpi_status status;
316
317         /*
318          * The FADT has multiple versions with different lengths,
319          * and it contains pointers to both the DSDT and FACS tables.
320          *
321          * Get a local copy of the FADT and convert it to a common format
322          * Map entire FADT, assumed to be smaller than one page.
323          */
324         fadt_desc = &acpi_gbl_root_table_list.tables[acpi_gbl_fadt_index];
325         status = acpi_tb_get_table(fadt_desc, &table);
326         if (ACPI_FAILURE(status)) {
327                 return;
328         }
329         length = fadt_desc->length;
330
331         /*
332          * Validate the FADT checksum before we copy the table. Ignore
333          * checksum error as we want to try to get the DSDT and FACS.
334          */
335         (void)acpi_tb_verify_checksum(table, length);
336
337         /* Create a local copy of the FADT in common ACPI 2.0+ format */
338
339         acpi_tb_create_local_fadt(table, length);
340
341         /* All done with the real FADT, unmap it */
342
343         acpi_tb_put_table(fadt_desc);
344
345         /* Obtain the DSDT and FACS tables via their addresses within the FADT */
346
347         acpi_tb_install_standard_table((acpi_physical_address)acpi_gbl_FADT.
348                                        Xdsdt,
349                                        ACPI_TABLE_ORIGIN_INTERNAL_PHYSICAL,
350                                        FALSE, TRUE, &acpi_gbl_dsdt_index);
351
352         /* If Hardware Reduced flag is set, there is no FACS */
353
354         if (!acpi_gbl_reduced_hardware) {
355                 if (acpi_gbl_FADT.facs) {
356                         acpi_tb_install_standard_table((acpi_physical_address)
357                                                        acpi_gbl_FADT.facs,
358                                                        ACPI_TABLE_ORIGIN_INTERNAL_PHYSICAL,
359                                                        FALSE, TRUE,
360                                                        &acpi_gbl_facs_index);
361                 }
362                 if (acpi_gbl_FADT.Xfacs) {
363                         acpi_tb_install_standard_table((acpi_physical_address)
364                                                        acpi_gbl_FADT.Xfacs,
365                                                        ACPI_TABLE_ORIGIN_INTERNAL_PHYSICAL,
366                                                        FALSE, TRUE,
367                                                        &acpi_gbl_xfacs_index);
368                 }
369         }
370 }
371
372 /*******************************************************************************
373  *
374  * FUNCTION:    acpi_tb_create_local_fadt
375  *
376  * PARAMETERS:  table               - Pointer to BIOS FADT
377  *              length              - Length of the table
378  *
379  * RETURN:      None
380  *
381  * DESCRIPTION: Get a local copy of the FADT and convert it to a common format.
382  *              Performs validation on some important FADT fields.
383  *
384  * NOTE:        We create a local copy of the FADT regardless of the version.
385  *
386  ******************************************************************************/
387
388 void acpi_tb_create_local_fadt(struct acpi_table_header *table, u32 length)
389 {
390         /*
391          * Check if the FADT is larger than the largest table that we expect
392          * (typically the current ACPI specification version). If so, truncate
393          * the table, and issue a warning.
394          */
395         if (length > sizeof(struct acpi_table_fadt)) {
396                 ACPI_BIOS_WARNING((AE_INFO,
397                                    "FADT (revision %u) is longer than %s length, "
398                                    "truncating length %u to %u",
399                                    table->revision, ACPI_FADT_CONFORMANCE,
400                                    length,
401                                    (u32)sizeof(struct acpi_table_fadt)));
402         }
403
404         /* Clear the entire local FADT */
405
406         memset(&acpi_gbl_FADT, 0, sizeof(struct acpi_table_fadt));
407
408         /* Copy the original FADT, up to sizeof (struct acpi_table_fadt) */
409
410         memcpy(&acpi_gbl_FADT, table,
411                ACPI_MIN(length, sizeof(struct acpi_table_fadt)));
412
413         /* Take a copy of the Hardware Reduced flag */
414
415         acpi_gbl_reduced_hardware = FALSE;
416         if (acpi_gbl_FADT.flags & ACPI_FADT_HW_REDUCED) {
417                 acpi_gbl_reduced_hardware = TRUE;
418         }
419
420         /* Convert the local copy of the FADT to the common internal format */
421
422         acpi_tb_convert_fadt();
423
424         /* Initialize the global ACPI register structures */
425
426         acpi_tb_setup_fadt_registers();
427 }
428
429 /*******************************************************************************
430  *
431  * FUNCTION:    acpi_tb_convert_fadt
432  *
433  * PARAMETERS:  none - acpi_gbl_FADT is used.
434  *
435  * RETURN:      None
436  *
437  * DESCRIPTION: Converts all versions of the FADT to a common internal format.
438  *              Expand 32-bit addresses to 64-bit as necessary. Also validate
439  *              important fields within the FADT.
440  *
441  * NOTE:        acpi_gbl_FADT must be of size (struct acpi_table_fadt), and must
442  *              contain a copy of the actual BIOS-provided FADT.
443  *
444  * Notes on 64-bit register addresses:
445  *
446  * After this FADT conversion, later ACPICA code will only use the 64-bit "X"
447  * fields of the FADT for all ACPI register addresses.
448  *
449  * The 64-bit X fields are optional extensions to the original 32-bit FADT
450  * V1.0 fields. Even if they are present in the FADT, they are optional and
451  * are unused if the BIOS sets them to zero. Therefore, we must copy/expand
452  * 32-bit V1.0 fields to the 64-bit X fields if the 64-bit X field is originally
453  * zero.
454  *
455  * For ACPI 1.0 FADTs (that contain no 64-bit addresses), all 32-bit address
456  * fields are expanded to the corresponding 64-bit X fields in the internal
457  * common FADT.
458  *
459  * For ACPI 2.0+ FADTs, all valid (non-zero) 32-bit address fields are expanded
460  * to the corresponding 64-bit X fields, if the 64-bit field is originally
461  * zero. Adhering to the ACPI specification, we completely ignore the 32-bit
462  * field if the 64-bit field is valid, regardless of whether the host OS is
463  * 32-bit or 64-bit.
464  *
465  * Possible additional checks:
466  *  (acpi_gbl_FADT.pm1_event_length >= 4)
467  *  (acpi_gbl_FADT.pm1_control_length >= 2)
468  *  (acpi_gbl_FADT.pm_timer_length >= 4)
469  *  Gpe block lengths must be multiple of 2
470  *
471  ******************************************************************************/
472
473 static void acpi_tb_convert_fadt(void)
474 {
475         const char *name;
476         struct acpi_generic_address *address64;
477         u32 address32;
478         u8 length;
479         u8 flags;
480         u32 i;
481
482         /*
483          * For ACPI 1.0 FADTs (revision 1 or 2), ensure that reserved fields which
484          * should be zero are indeed zero. This will workaround BIOSs that
485          * inadvertently place values in these fields.
486          *
487          * The ACPI 1.0 reserved fields that will be zeroed are the bytes located
488          * at offset 45, 55, 95, and the word located at offset 109, 110.
489          *
490          * Note: The FADT revision value is unreliable. Only the length can be
491          * trusted.
492          */
493         if (acpi_gbl_FADT.header.length <= ACPI_FADT_V2_SIZE) {
494                 acpi_gbl_FADT.preferred_profile = 0;
495                 acpi_gbl_FADT.pstate_control = 0;
496                 acpi_gbl_FADT.cst_control = 0;
497                 acpi_gbl_FADT.boot_flags = 0;
498         }
499
500         /*
501          * Now we can update the local FADT length to the length of the
502          * current FADT version as defined by the ACPI specification.
503          * Thus, we will have a common FADT internally.
504          */
505         acpi_gbl_FADT.header.length = sizeof(struct acpi_table_fadt);
506
507         /*
508          * Expand the 32-bit DSDT addresses to 64-bit as necessary.
509          * Later ACPICA code will always use the X 64-bit field.
510          */
511         acpi_gbl_FADT.Xdsdt = acpi_tb_select_address("DSDT",
512                                                      acpi_gbl_FADT.dsdt,
513                                                      acpi_gbl_FADT.Xdsdt);
514
515         /* If Hardware Reduced flag is set, we are all done */
516
517         if (acpi_gbl_reduced_hardware) {
518                 return;
519         }
520
521         /* Examine all of the 64-bit extended address fields (X fields) */
522
523         for (i = 0; i < ACPI_FADT_INFO_ENTRIES; i++) {
524                 /*
525                  * Get the 32-bit and 64-bit addresses, as well as the register
526                  * length and register name.
527                  */
528                 address32 = *ACPI_ADD_PTR(u32,
529                                           &acpi_gbl_FADT,
530                                           fadt_info_table[i].address32);
531
532                 address64 = ACPI_ADD_PTR(struct acpi_generic_address,
533                                          &acpi_gbl_FADT,
534                                          fadt_info_table[i].address64);
535
536                 length = *ACPI_ADD_PTR(u8,
537                                        &acpi_gbl_FADT,
538                                        fadt_info_table[i].length);
539
540                 name = fadt_info_table[i].name;
541                 flags = fadt_info_table[i].flags;
542
543                 /*
544                  * Expand the ACPI 1.0 32-bit addresses to the ACPI 2.0 64-bit "X"
545                  * generic address structures as necessary. Later code will always use
546                  * the 64-bit address structures.
547                  *
548                  * November 2013:
549                  * Now always use the 64-bit address if it is valid (non-zero), in
550                  * accordance with the ACPI specification which states that a 64-bit
551                  * address supersedes the 32-bit version. This behavior can be
552                  * overridden by the acpi_gbl_use32_bit_fadt_addresses flag.
553                  *
554                  * During 64-bit address construction and verification,
555                  * these cases are handled:
556                  *
557                  * Address32 zero, Address64 [don't care]   - Use Address64
558                  *
559                  * No override: if acpi_gbl_use32_bit_fadt_addresses is FALSE, and:
560                  * Address32 non-zero, Address64 zero       - Copy/use Address32
561                  * Address32 non-zero == Address64 non-zero - Use Address64
562                  * Address32 non-zero != Address64 non-zero - Warning, use Address64
563                  *
564                  * Override: if acpi_gbl_use32_bit_fadt_addresses is TRUE, and:
565                  * Address32 non-zero, Address64 zero       - Copy/use Address32
566                  * Address32 non-zero == Address64 non-zero - Copy/use Address32
567                  * Address32 non-zero != Address64 non-zero - Warning, copy/use Address32
568                  *
569                  * Note: space_id is always I/O for 32-bit legacy address fields
570                  */
571                 if (address32) {
572                         if (address64->address) {
573                                 if (address64->address != (u64)address32) {
574
575                                         /* Address mismatch */
576
577                                         ACPI_BIOS_WARNING((AE_INFO,
578                                                            "32/64X address mismatch in FADT/%s: "
579                                                            "0x%8.8X/0x%8.8X%8.8X, using %u-bit address",
580                                                            name, address32,
581                                                            ACPI_FORMAT_UINT64
582                                                            (address64->address),
583                                                            acpi_gbl_use32_bit_fadt_addresses
584                                                            ? 32 : 64));
585                                 }
586
587                                 /*
588                                  * For each extended field, check for length mismatch
589                                  * between the legacy length field and the corresponding
590                                  * 64-bit X length field.
591                                  * Note: If the legacy length field is > 0xFF bits, ignore
592                                  * this check. (GPE registers can be larger than the
593                                  * 64-bit GAS structure can accomodate, 0xFF bits).
594                                  */
595                                 if ((ACPI_MUL_8(length) <= ACPI_UINT8_MAX) &&
596                                     (address64->bit_width !=
597                                      ACPI_MUL_8(length))) {
598                                         ACPI_BIOS_WARNING((AE_INFO,
599                                                            "32/64X length mismatch in FADT/%s: %u/%u",
600                                                            name,
601                                                            ACPI_MUL_8(length),
602                                                            address64->
603                                                            bit_width));
604                                 }
605                         }
606
607                         /*
608                          * Hardware register access code always uses the 64-bit fields.
609                          * So if the 64-bit field is zero or is to be overridden,
610                          * initialize it with the 32-bit fields.
611                          * Note that when the 32-bit address favor is specified, the
612                          * 64-bit fields are always re-initialized so that
613                          * access_size/bit_width/bit_offset fields can be correctly
614                          * configured to the values to trigger a 32-bit compatible
615                          * access mode in the hardware register access code.
616                          */
617                         if (!address64->address
618                             || acpi_gbl_use32_bit_fadt_addresses) {
619                                 acpi_tb_init_generic_address(address64,
620                                                              ACPI_ADR_SPACE_SYSTEM_IO,
621                                                              length,
622                                                              (u64)address32,
623                                                              name, flags);
624                         }
625                 }
626
627                 if (fadt_info_table[i].flags & ACPI_FADT_REQUIRED) {
628                         /*
629                          * Field is required (Pm1a_event, Pm1a_control).
630                          * Both the address and length must be non-zero.
631                          */
632                         if (!address64->address || !length) {
633                                 ACPI_BIOS_ERROR((AE_INFO,
634                                                  "Required FADT field %s has zero address and/or length: "
635                                                  "0x%8.8X%8.8X/0x%X",
636                                                  name,
637                                                  ACPI_FORMAT_UINT64(address64->
638                                                                     address),
639                                                  length));
640                         }
641                 } else if (fadt_info_table[i].flags & ACPI_FADT_SEPARATE_LENGTH) {
642                         /*
643                          * Field is optional (Pm2_control, GPE0, GPE1) AND has its own
644                          * length field. If present, both the address and length must
645                          * be valid.
646                          */
647                         if ((address64->address && !length) ||
648                             (!address64->address && length)) {
649                                 ACPI_BIOS_WARNING((AE_INFO,
650                                                    "Optional FADT field %s has valid %s but zero %s: "
651                                                    "0x%8.8X%8.8X/0x%X", name,
652                                                    (length ? "Length" :
653                                                     "Address"),
654                                                    (length ? "Address" :
655                                                     "Length"),
656                                                    ACPI_FORMAT_UINT64
657                                                    (address64->address),
658                                                    length));
659                         }
660                 }
661         }
662 }
663
664 /*******************************************************************************
665  *
666  * FUNCTION:    acpi_tb_setup_fadt_registers
667  *
668  * PARAMETERS:  None, uses acpi_gbl_FADT.
669  *
670  * RETURN:      None
671  *
672  * DESCRIPTION: Initialize global ACPI PM1 register definitions. Optionally,
673  *              force FADT register definitions to their default lengths.
674  *
675  ******************************************************************************/
676
677 static void acpi_tb_setup_fadt_registers(void)
678 {
679         struct acpi_generic_address *target64;
680         struct acpi_generic_address *source64;
681         u8 pm1_register_byte_width;
682         u32 i;
683
684         /*
685          * Optionally check all register lengths against the default values and
686          * update them if they are incorrect.
687          */
688         if (acpi_gbl_use_default_register_widths) {
689                 for (i = 0; i < ACPI_FADT_INFO_ENTRIES; i++) {
690                         target64 =
691                             ACPI_ADD_PTR(struct acpi_generic_address,
692                                          &acpi_gbl_FADT,
693                                          fadt_info_table[i].address64);
694
695                         /*
696                          * If a valid register (Address != 0) and the (default_length > 0)
697                          * (Not a GPE register), then check the width against the default.
698                          */
699                         if ((target64->address) &&
700                             (fadt_info_table[i].default_length > 0) &&
701                             (fadt_info_table[i].default_length !=
702                              target64->bit_width)) {
703                                 ACPI_BIOS_WARNING((AE_INFO,
704                                                    "Invalid length for FADT/%s: %u, using default %u",
705                                                    fadt_info_table[i].name,
706                                                    target64->bit_width,
707                                                    fadt_info_table[i].
708                                                    default_length));
709
710                                 /* Incorrect size, set width to the default */
711
712                                 target64->bit_width =
713                                     fadt_info_table[i].default_length;
714                         }
715                 }
716         }
717
718         /*
719          * Get the length of the individual PM1 registers (enable and status).
720          * Each register is defined to be (event block length / 2). Extra divide
721          * by 8 converts bits to bytes.
722          */
723         pm1_register_byte_width = (u8)
724             ACPI_DIV_16(acpi_gbl_FADT.xpm1a_event_block.bit_width);
725
726         /*
727          * Calculate separate GAS structs for the PM1x (A/B) Status and Enable
728          * registers. These addresses do not appear (directly) in the FADT, so it
729          * is useful to pre-calculate them from the PM1 Event Block definitions.
730          *
731          * The PM event blocks are split into two register blocks, first is the
732          * PM Status Register block, followed immediately by the PM Enable
733          * Register block. Each is of length (pm1_event_length/2)
734          *
735          * Note: The PM1A event block is required by the ACPI specification.
736          * However, the PM1B event block is optional and is rarely, if ever,
737          * used.
738          */
739
740         for (i = 0; i < ACPI_FADT_PM_INFO_ENTRIES; i++) {
741                 source64 =
742                     ACPI_ADD_PTR(struct acpi_generic_address, &acpi_gbl_FADT,
743                                  fadt_pm_info_table[i].source);
744
745                 if (source64->address) {
746                         acpi_tb_init_generic_address(fadt_pm_info_table[i].
747                                                      target, source64->space_id,
748                                                      pm1_register_byte_width,
749                                                      source64->address +
750                                                      (fadt_pm_info_table[i].
751                                                       register_num *
752                                                       pm1_register_byte_width),
753                                                      "PmRegisters", 0);
754                 }
755         }
756 }