1 /******************************************************************************
2  *
3  * Module Name: tbfadt   - FADT table utilities
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2012, 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 ACPI_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 static void acpi_tb_setup_fadt_registers(void);
61 
62 /* Table for conversion of FADT to common internal format and FADT validation */
63 
64 typedef struct acpi_fadt_info {
65 	char *name;
66 	u16 address64;
67 	u16 address32;
68 	u16 length;
69 	u8 default_length;
70 	u8 type;
71 
72 } acpi_fadt_info;
73 
74 #define ACPI_FADT_OPTIONAL          0
75 #define ACPI_FADT_REQUIRED          1
76 #define ACPI_FADT_SEPARATE_LENGTH   2
77 
78 static struct acpi_fadt_info fadt_info_table[] = {
79 	{"Pm1aEventBlock",
80 	 ACPI_FADT_OFFSET(xpm1a_event_block),
81 	 ACPI_FADT_OFFSET(pm1a_event_block),
82 	 ACPI_FADT_OFFSET(pm1_event_length),
83 	 ACPI_PM1_REGISTER_WIDTH * 2,	/* Enable + Status register */
84 	 ACPI_FADT_REQUIRED},
85 
86 	{"Pm1bEventBlock",
87 	 ACPI_FADT_OFFSET(xpm1b_event_block),
88 	 ACPI_FADT_OFFSET(pm1b_event_block),
89 	 ACPI_FADT_OFFSET(pm1_event_length),
90 	 ACPI_PM1_REGISTER_WIDTH * 2,	/* Enable + Status register */
91 	 ACPI_FADT_OPTIONAL},
92 
93 	{"Pm1aControlBlock",
94 	 ACPI_FADT_OFFSET(xpm1a_control_block),
95 	 ACPI_FADT_OFFSET(pm1a_control_block),
96 	 ACPI_FADT_OFFSET(pm1_control_length),
97 	 ACPI_PM1_REGISTER_WIDTH,
98 	 ACPI_FADT_REQUIRED},
99 
100 	{"Pm1bControlBlock",
101 	 ACPI_FADT_OFFSET(xpm1b_control_block),
102 	 ACPI_FADT_OFFSET(pm1b_control_block),
103 	 ACPI_FADT_OFFSET(pm1_control_length),
104 	 ACPI_PM1_REGISTER_WIDTH,
105 	 ACPI_FADT_OPTIONAL},
106 
107 	{"Pm2ControlBlock",
108 	 ACPI_FADT_OFFSET(xpm2_control_block),
109 	 ACPI_FADT_OFFSET(pm2_control_block),
110 	 ACPI_FADT_OFFSET(pm2_control_length),
111 	 ACPI_PM2_REGISTER_WIDTH,
112 	 ACPI_FADT_SEPARATE_LENGTH},
113 
114 	{"PmTimerBlock",
115 	 ACPI_FADT_OFFSET(xpm_timer_block),
116 	 ACPI_FADT_OFFSET(pm_timer_block),
117 	 ACPI_FADT_OFFSET(pm_timer_length),
118 	 ACPI_PM_TIMER_WIDTH,
119 	 ACPI_FADT_REQUIRED},
120 
121 	{"Gpe0Block",
122 	 ACPI_FADT_OFFSET(xgpe0_block),
123 	 ACPI_FADT_OFFSET(gpe0_block),
124 	 ACPI_FADT_OFFSET(gpe0_block_length),
125 	 0,
126 	 ACPI_FADT_SEPARATE_LENGTH},
127 
128 	{"Gpe1Block",
129 	 ACPI_FADT_OFFSET(xgpe1_block),
130 	 ACPI_FADT_OFFSET(gpe1_block),
131 	 ACPI_FADT_OFFSET(gpe1_block_length),
132 	 0,
133 	 ACPI_FADT_SEPARATE_LENGTH}
134 };
135 
136 #define ACPI_FADT_INFO_ENTRIES \
137 			(sizeof (fadt_info_table) / sizeof (struct acpi_fadt_info))
138 
139 /* Table used to split Event Blocks into separate status/enable registers */
140 
141 typedef struct acpi_fadt_pm_info {
142 	struct acpi_generic_address *target;
143 	u16 source;
144 	u8 register_num;
145 
146 } acpi_fadt_pm_info;
147 
148 static struct acpi_fadt_pm_info fadt_pm_info_table[] = {
149 	{&acpi_gbl_xpm1a_status,
150 	 ACPI_FADT_OFFSET(xpm1a_event_block),
151 	 0},
152 
153 	{&acpi_gbl_xpm1a_enable,
154 	 ACPI_FADT_OFFSET(xpm1a_event_block),
155 	 1},
156 
157 	{&acpi_gbl_xpm1b_status,
158 	 ACPI_FADT_OFFSET(xpm1b_event_block),
159 	 0},
160 
161 	{&acpi_gbl_xpm1b_enable,
162 	 ACPI_FADT_OFFSET(xpm1b_event_block),
163 	 1}
164 };
165 
166 #define ACPI_FADT_PM_INFO_ENTRIES \
167 			(sizeof (fadt_pm_info_table) / sizeof (struct acpi_fadt_pm_info))
168 
169 /*******************************************************************************
170  *
171  * FUNCTION:    acpi_tb_init_generic_address
172  *
173  * PARAMETERS:  generic_address     - GAS struct to be initialized
174  *              byte_width          - Width of this register
175  *              Address             - Address of the register
176  *
177  * RETURN:      None
178  *
179  * DESCRIPTION: Initialize a Generic Address Structure (GAS)
180  *              See the ACPI specification for a full description and
181  *              definition of this structure.
182  *
183  ******************************************************************************/
184 
185 static ACPI_INLINE void
acpi_tb_init_generic_address(struct acpi_generic_address * generic_address,u8 space_id,u8 byte_width,u64 address)186 acpi_tb_init_generic_address(struct acpi_generic_address *generic_address,
187 			     u8 space_id, u8 byte_width, u64 address)
188 {
189 
190 	/*
191 	 * The 64-bit Address field is non-aligned in the byte packed
192 	 * GAS struct.
193 	 */
194 	ACPI_MOVE_64_TO_64(&generic_address->address, &address);
195 
196 	/* All other fields are byte-wide */
197 
198 	generic_address->space_id = space_id;
199 	generic_address->bit_width = (u8)ACPI_MUL_8(byte_width);
200 	generic_address->bit_offset = 0;
201 	generic_address->access_width = 0;	/* Access width ANY */
202 }
203 
204 /*******************************************************************************
205  *
206  * FUNCTION:    acpi_tb_parse_fadt
207  *
208  * PARAMETERS:  table_index         - Index for the FADT
209  *
210  * RETURN:      None
211  *
212  * DESCRIPTION: Initialize the FADT, DSDT and FACS tables
213  *              (FADT contains the addresses of the DSDT and FACS)
214  *
215  ******************************************************************************/
216 
acpi_tb_parse_fadt(u32 table_index)217 void acpi_tb_parse_fadt(u32 table_index)
218 {
219 	u32 length;
220 	struct acpi_table_header *table;
221 
222 	/*
223 	 * The FADT has multiple versions with different lengths,
224 	 * and it contains pointers to both the DSDT and FACS tables.
225 	 *
226 	 * Get a local copy of the FADT and convert it to a common format
227 	 * Map entire FADT, assumed to be smaller than one page.
228 	 */
229 	length = acpi_gbl_root_table_list.tables[table_index].length;
230 
231 	table =
232 	    acpi_os_map_memory(acpi_gbl_root_table_list.tables[table_index].
233 			       address, length);
234 	if (!table) {
235 		return;
236 	}
237 
238 	/*
239 	 * Validate the FADT checksum before we copy the table. Ignore
240 	 * checksum error as we want to try to get the DSDT and FACS.
241 	 */
242 	(void)acpi_tb_verify_checksum(table, length);
243 
244 	/* Create a local copy of the FADT in common ACPI 2.0+ format */
245 
246 	acpi_tb_create_local_fadt(table, length);
247 
248 	/* All done with the real FADT, unmap it */
249 
250 	acpi_os_unmap_memory(table, length);
251 
252 	/* Obtain the DSDT and FACS tables via their addresses within the FADT */
253 
254 	acpi_tb_install_table((acpi_physical_address) acpi_gbl_FADT.Xdsdt,
255 			      ACPI_SIG_DSDT, ACPI_TABLE_INDEX_DSDT);
256 
257 	/* If Hardware Reduced flag is set, there is no FACS */
258 
259 	if (!acpi_gbl_reduced_hardware) {
260 		acpi_tb_install_table((acpi_physical_address) acpi_gbl_FADT.
261 				      Xfacs, ACPI_SIG_FACS,
262 				      ACPI_TABLE_INDEX_FACS);
263 	}
264 }
265 
266 /*******************************************************************************
267  *
268  * FUNCTION:    acpi_tb_create_local_fadt
269  *
270  * PARAMETERS:  Table               - Pointer to BIOS FADT
271  *              Length              - Length of the table
272  *
273  * RETURN:      None
274  *
275  * DESCRIPTION: Get a local copy of the FADT and convert it to a common format.
276  *              Performs validation on some important FADT fields.
277  *
278  * NOTE:        We create a local copy of the FADT regardless of the version.
279  *
280  ******************************************************************************/
281 
acpi_tb_create_local_fadt(struct acpi_table_header * table,u32 length)282 void acpi_tb_create_local_fadt(struct acpi_table_header *table, u32 length)
283 {
284 	/*
285 	 * Check if the FADT is larger than the largest table that we expect
286 	 * (the ACPI 5.0 version). If so, truncate the table, and issue
287 	 * a warning.
288 	 */
289 	if (length > sizeof(struct acpi_table_fadt)) {
290 		ACPI_WARNING((AE_INFO,
291 			      "FADT (revision %u) is longer than ACPI 5.0 version, "
292 			      "truncating length %u to %u",
293 			      table->revision, length,
294 			      (u32)sizeof(struct acpi_table_fadt)));
295 	}
296 
297 	/* Clear the entire local FADT */
298 
299 	ACPI_MEMSET(&acpi_gbl_FADT, 0, sizeof(struct acpi_table_fadt));
300 
301 	/* Copy the original FADT, up to sizeof (struct acpi_table_fadt) */
302 
303 	ACPI_MEMCPY(&acpi_gbl_FADT, table,
304 		    ACPI_MIN(length, sizeof(struct acpi_table_fadt)));
305 
306 	/* Take a copy of the Hardware Reduced flag */
307 
308 	acpi_gbl_reduced_hardware = FALSE;
309 	if (acpi_gbl_FADT.flags & ACPI_FADT_HW_REDUCED) {
310 		acpi_gbl_reduced_hardware = TRUE;
311 	}
312 
313 	/* Convert the local copy of the FADT to the common internal format */
314 
315 	acpi_tb_convert_fadt();
316 
317 	/* Validate FADT values now, before we make any changes */
318 
319 	acpi_tb_validate_fadt();
320 
321 	/* Initialize the global ACPI register structures */
322 
323 	acpi_tb_setup_fadt_registers();
324 }
325 
326 /*******************************************************************************
327  *
328  * FUNCTION:    acpi_tb_convert_fadt
329  *
330  * PARAMETERS:  None, uses acpi_gbl_FADT
331  *
332  * RETURN:      None
333  *
334  * DESCRIPTION: Converts all versions of the FADT to a common internal format.
335  *              Expand 32-bit addresses to 64-bit as necessary.
336  *
337  * NOTE:        acpi_gbl_FADT must be of size (struct acpi_table_fadt),
338  *              and must contain a copy of the actual FADT.
339  *
340  * Notes on 64-bit register addresses:
341  *
342  * After this FADT conversion, later ACPICA code will only use the 64-bit "X"
343  * fields of the FADT for all ACPI register addresses.
344  *
345  * The 64-bit "X" fields are optional extensions to the original 32-bit FADT
346  * V1.0 fields. Even if they are present in the FADT, they are optional and
347  * are unused if the BIOS sets them to zero. Therefore, we must copy/expand
348  * 32-bit V1.0 fields if the corresponding X field is zero.
349  *
350  * For ACPI 1.0 FADTs, all 32-bit address fields are expanded to the
351  * corresponding "X" fields in the internal FADT.
352  *
353  * For ACPI 2.0+ FADTs, all valid (non-zero) 32-bit address fields are expanded
354  * to the corresponding 64-bit X fields. For compatibility with other ACPI
355  * implementations, we ignore the 64-bit field if the 32-bit field is valid,
356  * regardless of whether the host OS is 32-bit or 64-bit.
357  *
358  ******************************************************************************/
359 
acpi_tb_convert_fadt(void)360 static void acpi_tb_convert_fadt(void)
361 {
362 	struct acpi_generic_address *address64;
363 	u32 address32;
364 	u32 i;
365 
366 	/*
367 	 * Expand the 32-bit FACS and DSDT addresses to 64-bit as necessary.
368 	 * Later code will always use the X 64-bit field. Also, check for an
369 	 * address mismatch between the 32-bit and 64-bit address fields
370 	 * (FIRMWARE_CTRL/X_FIRMWARE_CTRL, DSDT/X_DSDT) which would indicate
371 	 * the presence of two FACS or two DSDT tables.
372 	 */
373 	if (!acpi_gbl_FADT.Xfacs) {
374 		acpi_gbl_FADT.Xfacs = (u64) acpi_gbl_FADT.facs;
375 	} else if (acpi_gbl_FADT.facs &&
376 		   (acpi_gbl_FADT.Xfacs != (u64) acpi_gbl_FADT.facs)) {
377 		ACPI_WARNING((AE_INFO,
378 		    "32/64 FACS address mismatch in FADT - two FACS tables!"));
379 	}
380 
381 	if (!acpi_gbl_FADT.Xdsdt) {
382 		acpi_gbl_FADT.Xdsdt = (u64) acpi_gbl_FADT.dsdt;
383 	} else if (acpi_gbl_FADT.dsdt &&
384 		   (acpi_gbl_FADT.Xdsdt != (u64) acpi_gbl_FADT.dsdt)) {
385 		ACPI_WARNING((AE_INFO,
386 		    "32/64 DSDT address mismatch in FADT - two DSDT tables!"));
387 	}
388 
389 	/*
390 	 * For ACPI 1.0 FADTs (revision 1 or 2), ensure that reserved fields which
391 	 * should be zero are indeed zero. This will workaround BIOSs that
392 	 * inadvertently place values in these fields.
393 	 *
394 	 * The ACPI 1.0 reserved fields that will be zeroed are the bytes located at
395 	 * offset 45, 55, 95, and the word located at offset 109, 110.
396 	 *
397 	 * Note: The FADT revision value is unreliable. Only the length can be
398 	 * trusted.
399 	 */
400 	if (acpi_gbl_FADT.header.length <= ACPI_FADT_V2_SIZE) {
401 		acpi_gbl_FADT.preferred_profile = 0;
402 		acpi_gbl_FADT.pstate_control = 0;
403 		acpi_gbl_FADT.cst_control = 0;
404 		acpi_gbl_FADT.boot_flags = 0;
405 	}
406 
407 	/* Update the local FADT table header length */
408 
409 	acpi_gbl_FADT.header.length = sizeof(struct acpi_table_fadt);
410 
411 	/*
412 	 * Expand the ACPI 1.0 32-bit addresses to the ACPI 2.0 64-bit "X"
413 	 * generic address structures as necessary. Later code will always use
414 	 * the 64-bit address structures.
415 	 *
416 	 * March 2009:
417 	 * We now always use the 32-bit address if it is valid (non-null). This
418 	 * is not in accordance with the ACPI specification which states that
419 	 * the 64-bit address supersedes the 32-bit version, but we do this for
420 	 * compatibility with other ACPI implementations. Most notably, in the
421 	 * case where both the 32 and 64 versions are non-null, we use the 32-bit
422 	 * version. This is the only address that is guaranteed to have been
423 	 * tested by the BIOS manufacturer.
424 	 */
425 	for (i = 0; i < ACPI_FADT_INFO_ENTRIES; i++) {
426 		address32 = *ACPI_ADD_PTR(u32,
427 					  &acpi_gbl_FADT,
428 					  fadt_info_table[i].address32);
429 
430 		address64 = ACPI_ADD_PTR(struct acpi_generic_address,
431 					 &acpi_gbl_FADT,
432 					 fadt_info_table[i].address64);
433 
434 		/*
435 		 * If both 32- and 64-bit addresses are valid (non-zero),
436 		 * they must match.
437 		 */
438 		if (address64->address && address32 &&
439 		    (address64->address != (u64) address32)) {
440 			ACPI_ERROR((AE_INFO,
441 				    "32/64X address mismatch in %s: 0x%8.8X/0x%8.8X%8.8X, using 32",
442 				    fadt_info_table[i].name, address32,
443 				    ACPI_FORMAT_UINT64(address64->address)));
444 		}
445 
446 		/* Always use 32-bit address if it is valid (non-null) */
447 
448 		if (address32) {
449 			/*
450 			 * Copy the 32-bit address to the 64-bit GAS structure. The
451 			 * Space ID is always I/O for 32-bit legacy address fields
452 			*/
453 			acpi_tb_init_generic_address(address64,
454 						     ACPI_ADR_SPACE_SYSTEM_IO,
455 						     *ACPI_ADD_PTR(u8,
456 								   &acpi_gbl_FADT,
457 								   fadt_info_table
458 								   [i].length),
459 						     (u64) address32);
460 		}
461 	}
462 }
463 
464 /*******************************************************************************
465  *
466  * FUNCTION:    acpi_tb_validate_fadt
467  *
468  * PARAMETERS:  Table           - Pointer to the FADT to be validated
469  *
470  * RETURN:      None
471  *
472  * DESCRIPTION: Validate various important fields within the FADT. If a problem
473  *              is found, issue a message, but no status is returned.
474  *              Used by both the table manager and the disassembler.
475  *
476  * Possible additional checks:
477  * (acpi_gbl_FADT.pm1_event_length >= 4)
478  * (acpi_gbl_FADT.pm1_control_length >= 2)
479  * (acpi_gbl_FADT.pm_timer_length >= 4)
480  * Gpe block lengths must be multiple of 2
481  *
482  ******************************************************************************/
483 
acpi_tb_validate_fadt(void)484 static void acpi_tb_validate_fadt(void)
485 {
486 	char *name;
487 	struct acpi_generic_address *address64;
488 	u8 length;
489 	u32 i;
490 
491 	/*
492 	 * Check for FACS and DSDT address mismatches. An address mismatch between
493 	 * the 32-bit and 64-bit address fields (FIRMWARE_CTRL/X_FIRMWARE_CTRL and
494 	 * DSDT/X_DSDT) would indicate the presence of two FACS or two DSDT tables.
495 	 */
496 	if (acpi_gbl_FADT.facs &&
497 	    (acpi_gbl_FADT.Xfacs != (u64) acpi_gbl_FADT.facs)) {
498 		ACPI_WARNING((AE_INFO,
499 			      "32/64X FACS address mismatch in FADT - "
500 			      "0x%8.8X/0x%8.8X%8.8X, using 32",
501 			      acpi_gbl_FADT.facs,
502 			      ACPI_FORMAT_UINT64(acpi_gbl_FADT.Xfacs)));
503 
504 		acpi_gbl_FADT.Xfacs = (u64) acpi_gbl_FADT.facs;
505 	}
506 
507 	if (acpi_gbl_FADT.dsdt &&
508 	    (acpi_gbl_FADT.Xdsdt != (u64) acpi_gbl_FADT.dsdt)) {
509 		ACPI_WARNING((AE_INFO,
510 			      "32/64X DSDT address mismatch in FADT - "
511 			      "0x%8.8X/0x%8.8X%8.8X, using 32",
512 			      acpi_gbl_FADT.dsdt,
513 			      ACPI_FORMAT_UINT64(acpi_gbl_FADT.Xdsdt)));
514 
515 		acpi_gbl_FADT.Xdsdt = (u64) acpi_gbl_FADT.dsdt;
516 	}
517 
518 	/* If Hardware Reduced flag is set, we are all done */
519 
520 	if (acpi_gbl_reduced_hardware) {
521 		return;
522 	}
523 
524 	/* Examine all of the 64-bit extended address fields (X fields) */
525 
526 	for (i = 0; i < ACPI_FADT_INFO_ENTRIES; i++) {
527 		/*
528 		 * Generate pointer to the 64-bit address, get the register
529 		 * length (width) and the register name
530 		 */
531 		address64 = ACPI_ADD_PTR(struct acpi_generic_address,
532 					 &acpi_gbl_FADT,
533 					 fadt_info_table[i].address64);
534 		length =
535 		    *ACPI_ADD_PTR(u8, &acpi_gbl_FADT,
536 				  fadt_info_table[i].length);
537 		name = fadt_info_table[i].name;
538 
539 		/*
540 		 * For each extended field, check for length mismatch between the
541 		 * legacy length field and the corresponding 64-bit X length field.
542 		 */
543 		if (address64->address &&
544 		    (address64->bit_width != ACPI_MUL_8(length))) {
545 			ACPI_WARNING((AE_INFO,
546 				      "32/64X length mismatch in %s: %u/%u",
547 				      name, ACPI_MUL_8(length),
548 				      address64->bit_width));
549 		}
550 
551 		if (fadt_info_table[i].type & ACPI_FADT_REQUIRED) {
552 			/*
553 			 * Field is required (Pm1a_event, Pm1a_control, pm_timer).
554 			 * Both the address and length must be non-zero.
555 			 */
556 			if (!address64->address || !length) {
557 				ACPI_ERROR((AE_INFO,
558 					    "Required field %s has zero address and/or length:"
559 					    " 0x%8.8X%8.8X/0x%X",
560 					    name,
561 					    ACPI_FORMAT_UINT64(address64->
562 							       address),
563 					    length));
564 			}
565 		} else if (fadt_info_table[i].type & ACPI_FADT_SEPARATE_LENGTH) {
566 			/*
567 			 * Field is optional (PM2Control, GPE0, GPE1) AND has its own
568 			 * length field. If present, both the address and length must
569 			 * be valid.
570 			 */
571 			if ((address64->address && !length) ||
572 			    (!address64->address && length)) {
573 				ACPI_WARNING((AE_INFO,
574 					      "Optional field %s has zero address or length: "
575 					      "0x%8.8X%8.8X/0x%X",
576 					      name,
577 					      ACPI_FORMAT_UINT64(address64->
578 								 address),
579 					      length));
580 			}
581 		}
582 	}
583 }
584 
585 /*******************************************************************************
586  *
587  * FUNCTION:    acpi_tb_setup_fadt_registers
588  *
589  * PARAMETERS:  None, uses acpi_gbl_FADT.
590  *
591  * RETURN:      None
592  *
593  * DESCRIPTION: Initialize global ACPI PM1 register definitions. Optionally,
594  *              force FADT register definitions to their default lengths.
595  *
596  ******************************************************************************/
597 
acpi_tb_setup_fadt_registers(void)598 static void acpi_tb_setup_fadt_registers(void)
599 {
600 	struct acpi_generic_address *target64;
601 	struct acpi_generic_address *source64;
602 	u8 pm1_register_byte_width;
603 	u32 i;
604 
605 	/*
606 	 * Optionally check all register lengths against the default values and
607 	 * update them if they are incorrect.
608 	 */
609 	if (acpi_gbl_use_default_register_widths) {
610 		for (i = 0; i < ACPI_FADT_INFO_ENTRIES; i++) {
611 			target64 =
612 			    ACPI_ADD_PTR(struct acpi_generic_address,
613 					 &acpi_gbl_FADT,
614 					 fadt_info_table[i].address64);
615 
616 			/*
617 			 * If a valid register (Address != 0) and the (default_length > 0)
618 			 * (Not a GPE register), then check the width against the default.
619 			 */
620 			if ((target64->address) &&
621 			    (fadt_info_table[i].default_length > 0) &&
622 			    (fadt_info_table[i].default_length !=
623 			     target64->bit_width)) {
624 				ACPI_WARNING((AE_INFO,
625 					      "Invalid length for %s: %u, using default %u",
626 					      fadt_info_table[i].name,
627 					      target64->bit_width,
628 					      fadt_info_table[i].
629 					      default_length));
630 
631 				/* Incorrect size, set width to the default */
632 
633 				target64->bit_width =
634 				    fadt_info_table[i].default_length;
635 			}
636 		}
637 	}
638 
639 	/*
640 	 * Get the length of the individual PM1 registers (enable and status).
641 	 * Each register is defined to be (event block length / 2). Extra divide
642 	 * by 8 converts bits to bytes.
643 	 */
644 	pm1_register_byte_width = (u8)
645 	    ACPI_DIV_16(acpi_gbl_FADT.xpm1a_event_block.bit_width);
646 
647 	/*
648 	 * Calculate separate GAS structs for the PM1x (A/B) Status and Enable
649 	 * registers. These addresses do not appear (directly) in the FADT, so it
650 	 * is useful to pre-calculate them from the PM1 Event Block definitions.
651 	 *
652 	 * The PM event blocks are split into two register blocks, first is the
653 	 * PM Status Register block, followed immediately by the PM Enable
654 	 * Register block. Each is of length (pm1_event_length/2)
655 	 *
656 	 * Note: The PM1A event block is required by the ACPI specification.
657 	 * However, the PM1B event block is optional and is rarely, if ever,
658 	 * used.
659 	 */
660 
661 	for (i = 0; i < ACPI_FADT_PM_INFO_ENTRIES; i++) {
662 		source64 =
663 		    ACPI_ADD_PTR(struct acpi_generic_address, &acpi_gbl_FADT,
664 				 fadt_pm_info_table[i].source);
665 
666 		if (source64->address) {
667 			acpi_tb_init_generic_address(fadt_pm_info_table[i].
668 						     target, source64->space_id,
669 						     pm1_register_byte_width,
670 						     source64->address +
671 						     (fadt_pm_info_table[i].
672 						      register_num *
673 						      pm1_register_byte_width));
674 		}
675 	}
676 }
677