Merge branch 'drivers-platform' into release
[linux-2.6] / drivers / acpi / acpica / tbfadt.c
1 /******************************************************************************
2  *
3  * Module Name: tbfadt   - FADT table utilities
4  *
5  *****************************************************************************/
6
7 /*
8  * Copyright (C) 2000 - 2008, 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 inline void
53 acpi_tb_init_generic_address(struct acpi_generic_address *generic_address,
54                              u8 space_id, u8 byte_width, u64 address);
55
56 static void acpi_tb_convert_fadt(void);
57
58 static void acpi_tb_validate_fadt(void);
59
60 /* Table for conversion of FADT to common internal format and FADT validation */
61
62 typedef struct acpi_fadt_info {
63         char *name;
64         u8 address64;
65         u8 address32;
66         u8 length;
67         u8 default_length;
68         u8 type;
69
70 } acpi_fadt_info;
71
72 #define ACPI_FADT_REQUIRED          1
73 #define ACPI_FADT_SEPARATE_LENGTH   2
74
75 static struct acpi_fadt_info fadt_info_table[] = {
76         {"Pm1aEventBlock",
77          ACPI_FADT_OFFSET(xpm1a_event_block),
78          ACPI_FADT_OFFSET(pm1a_event_block),
79          ACPI_FADT_OFFSET(pm1_event_length),
80          ACPI_PM1_REGISTER_WIDTH * 2,   /* Enable + Status register */
81          ACPI_FADT_REQUIRED},
82
83         {"Pm1bEventBlock",
84          ACPI_FADT_OFFSET(xpm1b_event_block),
85          ACPI_FADT_OFFSET(pm1b_event_block),
86          ACPI_FADT_OFFSET(pm1_event_length),
87          ACPI_PM1_REGISTER_WIDTH * 2,   /* Enable + Status register */
88          0},
89
90         {"Pm1aControlBlock",
91          ACPI_FADT_OFFSET(xpm1a_control_block),
92          ACPI_FADT_OFFSET(pm1a_control_block),
93          ACPI_FADT_OFFSET(pm1_control_length),
94          ACPI_PM1_REGISTER_WIDTH,
95          ACPI_FADT_REQUIRED},
96
97         {"Pm1bControlBlock",
98          ACPI_FADT_OFFSET(xpm1b_control_block),
99          ACPI_FADT_OFFSET(pm1b_control_block),
100          ACPI_FADT_OFFSET(pm1_control_length),
101          ACPI_PM1_REGISTER_WIDTH,
102          0},
103
104         {"Pm2ControlBlock",
105          ACPI_FADT_OFFSET(xpm2_control_block),
106          ACPI_FADT_OFFSET(pm2_control_block),
107          ACPI_FADT_OFFSET(pm2_control_length),
108          ACPI_PM2_REGISTER_WIDTH,
109          ACPI_FADT_SEPARATE_LENGTH},
110
111         {"PmTimerBlock",
112          ACPI_FADT_OFFSET(xpm_timer_block),
113          ACPI_FADT_OFFSET(pm_timer_block),
114          ACPI_FADT_OFFSET(pm_timer_length),
115          ACPI_PM_TIMER_WIDTH,
116          ACPI_FADT_REQUIRED},
117
118         {"Gpe0Block",
119          ACPI_FADT_OFFSET(xgpe0_block),
120          ACPI_FADT_OFFSET(gpe0_block),
121          ACPI_FADT_OFFSET(gpe0_block_length),
122          0,
123          ACPI_FADT_SEPARATE_LENGTH},
124
125         {"Gpe1Block",
126          ACPI_FADT_OFFSET(xgpe1_block),
127          ACPI_FADT_OFFSET(gpe1_block),
128          ACPI_FADT_OFFSET(gpe1_block_length),
129          0,
130          ACPI_FADT_SEPARATE_LENGTH}
131 };
132
133 #define ACPI_FADT_INFO_ENTRIES        (sizeof (fadt_info_table) / sizeof (struct acpi_fadt_info))
134
135 /*******************************************************************************
136  *
137  * FUNCTION:    acpi_tb_init_generic_address
138  *
139  * PARAMETERS:  generic_address     - GAS struct to be initialized
140  *              byte_width          - Width of this register
141  *              Address             - Address of the register
142  *
143  * RETURN:      None
144  *
145  * DESCRIPTION: Initialize a Generic Address Structure (GAS)
146  *              See the ACPI specification for a full description and
147  *              definition of this structure.
148  *
149  ******************************************************************************/
150
151 static inline void
152 acpi_tb_init_generic_address(struct acpi_generic_address *generic_address,
153                              u8 space_id, u8 byte_width, u64 address)
154 {
155
156         /*
157          * The 64-bit Address field is non-aligned in the byte packed
158          * GAS struct.
159          */
160         ACPI_MOVE_64_TO_64(&generic_address->address, &address);
161
162         /* All other fields are byte-wide */
163
164         generic_address->space_id = space_id;
165         generic_address->bit_width = (u8)ACPI_MUL_8(byte_width);
166         generic_address->bit_offset = 0;
167         generic_address->access_width = 0;      /* Access width ANY */
168 }
169
170 /*******************************************************************************
171  *
172  * FUNCTION:    acpi_tb_parse_fadt
173  *
174  * PARAMETERS:  table_index         - Index for the FADT
175  *              Flags               - Flags
176  *
177  * RETURN:      None
178  *
179  * DESCRIPTION: Initialize the FADT, DSDT and FACS tables
180  *              (FADT contains the addresses of the DSDT and FACS)
181  *
182  ******************************************************************************/
183
184 void acpi_tb_parse_fadt(u32 table_index, u8 flags)
185 {
186         u32 length;
187         struct acpi_table_header *table;
188
189         /*
190          * The FADT has multiple versions with different lengths,
191          * and it contains pointers to both the DSDT and FACS tables.
192          *
193          * Get a local copy of the FADT and convert it to a common format
194          * Map entire FADT, assumed to be smaller than one page.
195          */
196         length = acpi_gbl_root_table_list.tables[table_index].length;
197
198         table =
199             acpi_os_map_memory(acpi_gbl_root_table_list.tables[table_index].
200                                address, length);
201         if (!table) {
202                 return;
203         }
204
205         /*
206          * Validate the FADT checksum before we copy the table. Ignore
207          * checksum error as we want to try to get the DSDT and FACS.
208          */
209         (void)acpi_tb_verify_checksum(table, length);
210
211         /* Obtain a local copy of the FADT in common ACPI 2.0+ format */
212
213         acpi_tb_create_local_fadt(table, length);
214
215         /* All done with the real FADT, unmap it */
216
217         acpi_os_unmap_memory(table, length);
218
219         /* Obtain the DSDT and FACS tables via their addresses within the FADT */
220
221         acpi_tb_install_table((acpi_physical_address) acpi_gbl_FADT.Xdsdt,
222                               flags, ACPI_SIG_DSDT, ACPI_TABLE_INDEX_DSDT);
223
224         acpi_tb_install_table((acpi_physical_address) acpi_gbl_FADT.Xfacs,
225                               flags, ACPI_SIG_FACS, ACPI_TABLE_INDEX_FACS);
226 }
227
228 /*******************************************************************************
229  *
230  * FUNCTION:    acpi_tb_create_local_fadt
231  *
232  * PARAMETERS:  Table               - Pointer to BIOS FADT
233  *              Length              - Length of the table
234  *
235  * RETURN:      None
236  *
237  * DESCRIPTION: Get a local copy of the FADT and convert it to a common format.
238  *              Performs validation on some important FADT fields.
239  *
240  * NOTE:        We create a local copy of the FADT regardless of the version.
241  *
242  ******************************************************************************/
243
244 void acpi_tb_create_local_fadt(struct acpi_table_header *table, u32 length)
245 {
246
247         /*
248          * Check if the FADT is larger than the largest table that we expect
249          * (the ACPI 2.0/3.0 version). If so, truncate the table, and issue
250          * a warning.
251          */
252         if (length > sizeof(struct acpi_table_fadt)) {
253                 ACPI_WARNING((AE_INFO,
254                               "FADT (revision %u) is longer than ACPI 2.0 version, "
255                               "truncating length 0x%X to 0x%zX",
256                               table->revision, (unsigned)length,
257                               sizeof(struct acpi_table_fadt)));
258         }
259
260         /* Clear the entire local FADT */
261
262         ACPI_MEMSET(&acpi_gbl_FADT, 0, sizeof(struct acpi_table_fadt));
263
264         /* Copy the original FADT, up to sizeof (struct acpi_table_fadt) */
265
266         ACPI_MEMCPY(&acpi_gbl_FADT, table,
267                     ACPI_MIN(length, sizeof(struct acpi_table_fadt)));
268
269         /*
270          * 1) Convert the local copy of the FADT to the common internal format
271          * 2) Validate some of the important values within the FADT
272          */
273         acpi_tb_convert_fadt();
274 }
275
276 /*******************************************************************************
277  *
278  * FUNCTION:    acpi_tb_convert_fadt
279  *
280  * PARAMETERS:  None, uses acpi_gbl_FADT
281  *
282  * RETURN:      None
283  *
284  * DESCRIPTION: Converts all versions of the FADT to a common internal format.
285  *              Expand all 32-bit addresses to 64-bit.
286  *
287  * NOTE:        acpi_gbl_FADT must be of size (struct acpi_table_fadt),
288  *              and must contain a copy of the actual FADT.
289  *
290  * ACPICA will use the "X" fields of the FADT for all addresses.
291  *
292  * "X" fields are optional extensions to the original V1.0 fields. Even if
293  * they are present in the structure, they can be optionally not used by
294  * setting them to zero. Therefore, we must selectively expand V1.0 fields
295  * if the corresponding X field is zero.
296  *
297  * For ACPI 1.0 FADTs, all address fields are expanded to the corresponding
298  * "X" fields.
299  *
300  * For ACPI 2.0 FADTs, any "X" fields that are NULL are filled in by
301  * expanding the corresponding ACPI 1.0 field.
302  *
303  ******************************************************************************/
304
305 static void acpi_tb_convert_fadt(void)
306 {
307         u8 pm1_register_bit_width;
308         u8 pm1_register_byte_width;
309         struct acpi_generic_address *target64;
310         u32 i;
311
312         /* Update the local FADT table header length */
313
314         acpi_gbl_FADT.header.length = sizeof(struct acpi_table_fadt);
315
316         /*
317          * Expand the 32-bit FACS and DSDT addresses to 64-bit as necessary.
318          * Later code will always use the X 64-bit field. Also, check for an
319          * address mismatch between the 32-bit and 64-bit address fields
320          * (FIRMWARE_CTRL/X_FIRMWARE_CTRL, DSDT/X_DSDT) which would indicate
321          * the presence of two FACS or two DSDT tables.
322          */
323         if (!acpi_gbl_FADT.Xfacs) {
324                 acpi_gbl_FADT.Xfacs = (u64) acpi_gbl_FADT.facs;
325         } else if (acpi_gbl_FADT.facs &&
326                    (acpi_gbl_FADT.Xfacs != (u64) acpi_gbl_FADT.facs)) {
327                 ACPI_WARNING((AE_INFO,
328                     "32/64 FACS address mismatch in FADT - two FACS tables!"));
329         }
330
331         if (!acpi_gbl_FADT.Xdsdt) {
332                 acpi_gbl_FADT.Xdsdt = (u64) acpi_gbl_FADT.dsdt;
333         } else if (acpi_gbl_FADT.dsdt &&
334                    (acpi_gbl_FADT.Xdsdt != (u64) acpi_gbl_FADT.dsdt)) {
335                 ACPI_WARNING((AE_INFO,
336                     "32/64 DSDT address mismatch in FADT - two DSDT tables!"));
337         }
338
339         /*
340          * For ACPI 1.0 FADTs (revision 1 or 2), ensure that reserved fields which
341          * should be zero are indeed zero. This will workaround BIOSs that
342          * inadvertently place values in these fields.
343          *
344          * The ACPI 1.0 reserved fields that will be zeroed are the bytes located at
345          * offset 45, 55, 95, and the word located at offset 109, 110.
346          */
347         if (acpi_gbl_FADT.header.revision < FADT2_REVISION_ID) {
348                 acpi_gbl_FADT.preferred_profile = 0;
349                 acpi_gbl_FADT.pstate_control = 0;
350                 acpi_gbl_FADT.cst_control = 0;
351                 acpi_gbl_FADT.boot_flags = 0;
352         }
353
354         /*
355          * Expand the ACPI 1.0 32-bit addresses to the ACPI 2.0 64-bit "X"
356          * generic address structures as necessary. Later code will always use
357          * the 64-bit address structures.
358          */
359         for (i = 0; i < ACPI_FADT_INFO_ENTRIES; i++) {
360                 target64 =
361                     ACPI_ADD_PTR(struct acpi_generic_address, &acpi_gbl_FADT,
362                                  fadt_info_table[i].address64);
363
364                 /* Expand only if the 64-bit X target is null */
365
366                 if (!target64->address) {
367
368                         /* The space_id is always I/O for the 32-bit legacy address fields */
369
370                         acpi_tb_init_generic_address(target64,
371                                                      ACPI_ADR_SPACE_SYSTEM_IO,
372                                                      *ACPI_ADD_PTR(u8,
373                                                                    &acpi_gbl_FADT,
374                                                                    fadt_info_table
375                                                                    [i].length),
376                                                      (u64) * ACPI_ADD_PTR(u32,
377                                                                           &acpi_gbl_FADT,
378                                                                           fadt_info_table
379                                                                           [i].
380                                                                           address32));
381                 }
382         }
383
384         /* Validate FADT values now, before we make any changes */
385
386         acpi_tb_validate_fadt();
387
388         /*
389          * Optionally check all register lengths against the default values and
390          * update them if they are incorrect.
391          */
392         if (acpi_gbl_use_default_register_widths) {
393                 for (i = 0; i < ACPI_FADT_INFO_ENTRIES; i++) {
394                         target64 =
395                             ACPI_ADD_PTR(struct acpi_generic_address,
396                                          &acpi_gbl_FADT,
397                                          fadt_info_table[i].address64);
398
399                         /*
400                          * If a valid register (Address != 0) and the (default_length > 0)
401                          * (Not a GPE register), then check the width against the default.
402                          */
403                         if ((target64->address) &&
404                             (fadt_info_table[i].default_length > 0) &&
405                             (fadt_info_table[i].default_length !=
406                              target64->bit_width)) {
407                                 ACPI_WARNING((AE_INFO,
408                                               "Invalid length for %s: %d, using default %d",
409                                               fadt_info_table[i].name,
410                                               target64->bit_width,
411                                               fadt_info_table[i].
412                                               default_length));
413
414                                 /* Incorrect size, set width to the default */
415
416                                 target64->bit_width =
417                                     fadt_info_table[i].default_length;
418                         }
419                 }
420         }
421
422         /*
423          * Get the length of the individual PM1 registers (enable and status).
424          * Each register is defined to be (event block length / 2).
425          */
426         pm1_register_bit_width =
427             (u8)ACPI_DIV_2(acpi_gbl_FADT.xpm1a_event_block.bit_width);
428         pm1_register_byte_width = (u8)ACPI_DIV_8(pm1_register_bit_width);
429
430         /*
431          * Adjust the lengths of the PM1 Event Blocks so that they can be used to
432          * access the PM1 status register(s). Use (width / 2)
433          */
434         acpi_gbl_FADT.xpm1a_event_block.bit_width = pm1_register_bit_width;
435         acpi_gbl_FADT.xpm1b_event_block.bit_width = pm1_register_bit_width;
436
437         /*
438          * Calculate separate GAS structs for the PM1 Enable registers.
439          * These addresses do not appear (directly) in the FADT, so it is
440          * useful to calculate them once, here.
441          *
442          * The PM event blocks are split into two register blocks, first is the
443          * PM Status Register block, followed immediately by the PM Enable
444          * Register block. Each is of length (xpm1x_event_block.bit_width/2).
445          *
446          * On various systems the v2 fields (and particularly the bit widths)
447          * cannot be relied upon, though. Hence resort to using the v1 length
448          * here (and warn about the inconsistency).
449          */
450         if (acpi_gbl_FADT.xpm1a_event_block.bit_width
451             != acpi_gbl_FADT.pm1_event_length * 8)
452                 printk(KERN_WARNING "FADT: "
453                        "X_PM1a_EVT_BLK.bit_width (%u) does not match"
454                        " PM1_EVT_LEN (%u)\n",
455                        acpi_gbl_FADT.xpm1a_event_block.bit_width,
456                        acpi_gbl_FADT.pm1_event_length);
457
458         /* The PM1A register block is required */
459
460         acpi_tb_init_generic_address(&acpi_gbl_xpm1a_enable,
461                                      acpi_gbl_FADT.xpm1a_event_block.space_id,
462                                      pm1_register_byte_width,
463                                      (acpi_gbl_FADT.xpm1a_event_block.address +
464                                       pm1_register_byte_width));
465         /* Don't forget to copy space_id of the GAS */
466         acpi_gbl_xpm1a_enable.space_id =
467             acpi_gbl_FADT.xpm1a_event_block.space_id;
468
469         /* The PM1B register block is optional, ignore if not present */
470
471         if (acpi_gbl_FADT.xpm1b_event_block.address) {
472                 if (acpi_gbl_FADT.xpm1b_event_block.bit_width
473                     != acpi_gbl_FADT.pm1_event_length * 8)
474                         printk(KERN_WARNING "FADT: "
475                                "X_PM1b_EVT_BLK.bit_width (%u) does not match"
476                                " PM1_EVT_LEN (%u)\n",
477                                acpi_gbl_FADT.xpm1b_event_block.bit_width,
478                                acpi_gbl_FADT.pm1_event_length);
479                 acpi_tb_init_generic_address(&acpi_gbl_xpm1b_enable,
480                                              acpi_gbl_FADT.xpm1b_event_block.space_id,
481                                              pm1_register_byte_width,
482                                              (acpi_gbl_FADT.xpm1b_event_block.
483                                               address + pm1_register_byte_width));
484                 /* Don't forget to copy space_id of the GAS */
485                 acpi_gbl_xpm1b_enable.space_id =
486                     acpi_gbl_FADT.xpm1b_event_block.space_id;
487
488         }
489 }
490
491 /******************************************************************************
492  *
493  * FUNCTION:    acpi_tb_validate_fadt
494  *
495  * PARAMETERS:  Table           - Pointer to the FADT to be validated
496  *
497  * RETURN:      None
498  *
499  * DESCRIPTION: Validate various important fields within the FADT. If a problem
500  *              is found, issue a message, but no status is returned.
501  *              Used by both the table manager and the disassembler.
502  *
503  * Possible additional checks:
504  * (acpi_gbl_FADT.pm1_event_length >= 4)
505  * (acpi_gbl_FADT.pm1_control_length >= 2)
506  * (acpi_gbl_FADT.pm_timer_length >= 4)
507  * Gpe block lengths must be multiple of 2
508  *
509  ******************************************************************************/
510
511 static void acpi_tb_validate_fadt(void)
512 {
513         char *name;
514         u32 *address32;
515         struct acpi_generic_address *address64;
516         u8 length;
517         u32 i;
518
519         /*
520          * Check for FACS and DSDT address mismatches. An address mismatch between
521          * the 32-bit and 64-bit address fields (FIRMWARE_CTRL/X_FIRMWARE_CTRL and
522          * DSDT/X_DSDT) would indicate the presence of two FACS or two DSDT tables.
523          */
524         if (acpi_gbl_FADT.facs &&
525             (acpi_gbl_FADT.Xfacs != (u64) acpi_gbl_FADT.facs)) {
526                 ACPI_WARNING((AE_INFO,
527                               "32/64X FACS address mismatch in FADT - "
528                               "two FACS tables! %8.8X/%8.8X%8.8X",
529                               acpi_gbl_FADT.facs,
530                               ACPI_FORMAT_UINT64(acpi_gbl_FADT.Xfacs)));
531         }
532
533         if (acpi_gbl_FADT.dsdt &&
534             (acpi_gbl_FADT.Xdsdt != (u64) acpi_gbl_FADT.dsdt)) {
535                 ACPI_WARNING((AE_INFO,
536                               "32/64X DSDT address mismatch in FADT - "
537                               "two DSDT tables! %8.8X/%8.8X%8.8X",
538                               acpi_gbl_FADT.dsdt,
539                               ACPI_FORMAT_UINT64(acpi_gbl_FADT.Xdsdt)));
540         }
541
542         /* Examine all of the 64-bit extended address fields (X fields) */
543
544         for (i = 0; i < ACPI_FADT_INFO_ENTRIES; i++) {
545                 /*
546                  * Generate pointers to the 32-bit and 64-bit addresses, get the
547                  * register length (width), and the register name
548                  */
549                 address64 = ACPI_ADD_PTR(struct acpi_generic_address,
550                                          &acpi_gbl_FADT,
551                                          fadt_info_table[i].address64);
552                 address32 =
553                     ACPI_ADD_PTR(u32, &acpi_gbl_FADT,
554                                  fadt_info_table[i].address32);
555                 length =
556                     *ACPI_ADD_PTR(u8, &acpi_gbl_FADT,
557                                   fadt_info_table[i].length);
558                 name = fadt_info_table[i].name;
559
560                 /*
561                  * For each extended field, check for length mismatch between the
562                  * legacy length field and the corresponding 64-bit X length field.
563                  */
564                 if (address64 && (address64->bit_width != ACPI_MUL_8(length))) {
565                         ACPI_WARNING((AE_INFO,
566                                       "32/64X length mismatch in %s: %d/%d",
567                                       name, ACPI_MUL_8(length),
568                                       address64->bit_width));
569                 }
570
571                 if (fadt_info_table[i].type & ACPI_FADT_REQUIRED) {
572                         /*
573                          * Field is required (Pm1a_event, Pm1a_control, pm_timer).
574                          * Both the address and length must be non-zero.
575                          */
576                         if (!address64->address || !length) {
577                                 ACPI_ERROR((AE_INFO,
578                                             "Required field %s has zero address and/or length: %8.8X%8.8X/%X",
579                                             name,
580                                             ACPI_FORMAT_UINT64(address64->
581                                                                address),
582                                             length));
583                         }
584                 } else if (fadt_info_table[i].type & ACPI_FADT_SEPARATE_LENGTH) {
585                         /*
586                          * Field is optional (PM2Control, GPE0, GPE1) AND has its own
587                          * length field. If present, both the address and length must be valid.
588                          */
589                         if ((address64->address && !length)
590                             || (!address64->address && length)) {
591                                 ACPI_WARNING((AE_INFO,
592                                               "Optional field %s has zero address or length: %8.8X%8.8X/%X",
593                                               name,
594                                               ACPI_FORMAT_UINT64(address64->
595                                                                  address),
596                                               length));
597                         }
598                 }
599
600                 /* If both 32- and 64-bit addresses are valid (non-zero), they must match */
601
602                 if (address64->address && *address32 &&
603                     (address64->address != (u64) * address32)) {
604                         ACPI_ERROR((AE_INFO,
605                                     "32/64X address mismatch in %s: %8.8X/%8.8X%8.8X, using 64X",
606                                     name, *address32,
607                                     ACPI_FORMAT_UINT64(address64->address)));
608                 }
609         }
610 }