summaryrefslogtreecommitdiffstats
path: root/drivers/acpi/apei/apei-base.c
blob: 131c35ee9ed3d598c46a53986232de348f2f3b33 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
// SPDX-License-Identifier: GPL-2.0-only
/*
 * apei-base.c - ACPI Platform Error Interface (APEI) supporting
 * infrastructure
 *
 * APEI allows to report errors (for example from the chipset) to the
 * the operating system. This improves NMI handling especially. In
 * addition it supports error serialization and error injection.
 *
 * For more information about APEI, please refer to ACPI Specification
 * version 4.0, chapter 17.
 *
 * This file has Common functions used by more than one APEI table,
 * including framework of interpreter for ERST and EINJ; resource
 * management for APEI registers.
 *
 * Copyright (C) 2009, Intel Corp.
 *	Author: Huang Ying <ying.huang@intel.com>
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/acpi.h>
#include <linux/slab.h>
#include <linux/io.h>
#include <linux/kref.h>
#include <linux/rculist.h>
#include <linux/interrupt.h>
#include <linux/debugfs.h>
#include <asm/unaligned.h>

#include "apei-internal.h"

#define APEI_PFX "APEI: "

/*
 * APEI ERST (Error Record Serialization Table) and EINJ (Error
 * INJection) interpreter framework.
 */

#define APEI_EXEC_PRESERVE_REGISTER	0x1

void apei_exec_ctx_init(struct apei_exec_context *ctx,
			struct apei_exec_ins_type *ins_table,
			u32 instructions,
			struct acpi_whea_header *action_table,
			u32 entries)
{
	ctx->ins_table = ins_table;
	ctx->instructions = instructions;
	ctx->action_table = action_table;
	ctx->entries = entries;
}
EXPORT_SYMBOL_GPL(apei_exec_ctx_init);

int __apei_exec_read_register(struct acpi_whea_header *entry, u64 *val)
{
	int rc;

	rc = apei_read(val, &entry->register_region);
	if (rc)
		return rc;
	*val >>= entry->register_region.bit_offset;
	*val &= entry->mask;

	return 0;
}

int apei_exec_read_register(struct apei_exec_context *ctx,
			    struct acpi_whea_header *entry)
{
	int rc;
	u64 val = 0;

	rc = __apei_exec_read_register(entry, &val);
	if (rc)
		return rc;
	ctx->value = val;

	return 0;
}
EXPORT_SYMBOL_GPL(apei_exec_read_register);

int apei_exec_read_register_value(struct apei_exec_context *ctx,
				  struct acpi_whea_header *entry)
{
	int rc;

	rc = apei_exec_read_register(ctx, entry);
	if (rc)
		return rc;
	ctx->value = (ctx->value == entry->value);

	return 0;
}
EXPORT_SYMBOL_GPL(apei_exec_read_register_value);

int __apei_exec_write_register(struct acpi_whea_header *entry, u64 val)
{
	int rc;

	val &= entry->mask;
	val <<= entry->register_region.bit_offset;
	if (entry->flags & APEI_EXEC_PRESERVE_REGISTER) {
		u64 valr = 0;
		rc = apei_read(&valr, &entry->register_region);
		if (rc)
			return rc;
		valr &= ~(entry->mask << entry->register_region.bit_offset);
		val |= valr;
	}
	rc = apei_write(val, &entry->register_region);

	return rc;
}

int apei_exec_write_register(struct apei_exec_context *ctx,
			     struct acpi_whea_header *entry)
{
	return __apei_exec_write_register(entry, ctx->value);
}
EXPORT_SYMBOL_GPL(apei_exec_write_register);

int apei_exec_write_register_value(struct apei_exec_context *ctx,
				   struct acpi_whea_header *entry)
{
	int rc;

	ctx->value = entry->value;
	rc = apei_exec_write_register(ctx, entry);

	return rc;
}
EXPORT_SYMBOL_GPL(apei_exec_write_register_value);

int apei_exec_noop(struct apei_exec_context *ctx,
		   struct acpi_whea_header *entry)
{
	return 0;
}
EXPORT_SYMBOL_GPL(apei_exec_noop);

/*
 * Interpret the specified action. Go through whole action table,
 * execute all instructions belong to the action.
 */
int __apei_exec_run(struct apei_exec_context *ctx, u8 action,
		    bool optional)
{
	int rc = -ENOENT;
	u32 i, ip;
	struct acpi_whea_header *entry;
	apei_exec_ins_func_t run;

	ctx->ip = 0;

	/*
	 * "ip" is the instruction pointer of current instruction,
	 * "ctx->ip" specifies the next instruction to executed,
	 * instruction "run" function may change the "ctx->ip" to
	 * implement "goto" semantics.
	 */
rewind:
	ip = 0;
	for (i = 0; i < ctx->entries; i++) {
		entry = &ctx->action_table[i];
		if (entry->action != action)
			continue;
		if (ip == ctx->ip) {
			if (entry->instruction >= ctx->instructions ||
			    !ctx->ins_table[entry->instruction].run) {
				pr_warning(FW_WARN APEI_PFX
			"Invalid action table, unknown instruction type: %d\n",
					   entry->instruction);
				return -EINVAL;
			}
			run = ctx->ins_table[entry->instruction].run;
			rc = run(ctx, entry);
			if (rc < 0)
				return rc;
			else if (rc != APEI_EXEC_SET_IP)
				ctx->ip++;
		}
		ip++;
		if (ctx->ip < ip)
			goto rewind;
	}

	return !optional && rc < 0 ? rc : 0;
}
EXPORT_SYMBOL_GPL(__apei_exec_run);

typedef int (*apei_exec_entry_func_t)(struct apei_exec_context *ctx,
				      struct acpi_whea_header *entry,
				      void *data);

static int apei_exec_for_each_entry(struct apei_exec_context *ctx,
				    apei_exec_entry_func_t func,
				    void *data,
				    int *end)
{
	u8 ins;
	int i, rc;
	struct acpi_whea_header *entry;
	struct apei_exec_ins_type *ins_table = ctx->ins_table;

	for (i = 0; i < ctx->entries; i++) {
		entry = ctx->action_table + i;
		ins = entry->instruction;
		if (end)
			*end = i;
		if (ins >= ctx->instructions || !ins_table[ins].run) {
			pr_warning(FW_WARN APEI_PFX
			"Invalid action table, unknown instruction type: %d\n",
				   ins);
			return -EINVAL;
		}
		rc = func(ctx, entry, data);
		if (rc)
			return rc;
	}

	return 0;
}

static int pre_map_gar_callback(struct apei_exec_context *ctx,
				struct acpi_whea_header *entry,
				void *data)
{
	u8 ins = entry->instruction;

	if (ctx->ins_table[ins].flags & APEI_EXEC_INS_ACCESS_REGISTER)
		return apei_map_generic_address(&entry->register_region);

	return 0;
}

/*
 * Pre-map all GARs in action table to make it possible to access them
 * in NMI handler.
 */
int apei_exec_pre_map_gars(struct apei_exec_context *ctx)
{
	int rc, end;

	rc = apei_exec_for_each_entry(ctx, pre_map_gar_callback,
				      NULL, &end);
	if (rc) {
		struct apei_exec_context ctx_unmap;
		memcpy(&ctx_unmap, ctx, sizeof(*ctx));
		ctx_unmap.entries = end;
		apei_exec_post_unmap_gars(&ctx_unmap);
	}

	return rc;
}
EXPORT_SYMBOL_GPL(apei_exec_pre_map_gars);

static int post_unmap_gar_callback(struct apei_exec_context *ctx,
				   struct acpi_whea_header *entry,
				   void *data)
{
	u8 ins = entry->instruction;

	if (ctx->ins_table[ins].flags & APEI_EXEC_INS_ACCESS_REGISTER)
		apei_unmap_generic_address(&entry->register_region);

	return 0;
}

/* Post-unmap all GAR in action table. */
int apei_exec_post_unmap_gars(struct apei_exec_context *ctx)
{
	return apei_exec_for_each_entry(ctx, post_unmap_gar_callback,
					NULL, NULL);
}
EXPORT_SYMBOL_GPL(apei_exec_post_unmap_gars);

/*
 * Resource management for GARs in APEI
 */
struct apei_res {
	struct list_head list;
	unsigned long start;
	unsigned long end;
};

/* Collect all resources requested, to avoid conflict */
struct apei_resources apei_resources_all = {
	.iomem = LIST_HEAD_INIT(apei_resources_all.iomem),
	.ioport = LIST_HEAD_INIT(apei_resources_all.ioport),
};

static int apei_res_add(struct list_head *res_list,
			unsigned long start, unsigned long size)
{
	struct apei_res *res, *resn, *res_ins = NULL;
	unsigned long end = start + size;

	if (end <= start)
		return 0;
repeat:
	list_for_each_entry_safe(res, resn, res_list, list) {
		if (res->start > end || res->end < start)
			continue;
		else if (end <= res->end && start >= res->start) {
			kfree(res_ins);
			return 0;
		}
		list_del(&res->list);
		res->start = start = min(res->start, start);
		res->end = end = max(res->end, end);
		kfree(res_ins);
		res_ins = res;
		goto repeat;
	}

	if (res_ins)
		list_add(&res_ins->list, res_list);
	else {
		res_ins = kmalloc(sizeof(*res), GFP_KERNEL);
		if (!res_ins)
			return -ENOMEM;
		res_ins->start = start;
		res_ins->end = end;
		list_add(&res_ins->list, res_list);
	}

	return 0;
}

static int apei_res_sub(struct list_head *res_list1,
			struct list_head *res_list2)
{
	struct apei_res *res1, *resn1, *res2, *res;
	res1 = list_entry(res_list1->next, struct apei_res, list);
	resn1 = list_entry(res1->list.next, struct apei_res, list);
	while (&res1->list != res_list1) {
		list_for_each_entry(res2, res_list2, list) {
			if (res1->start >= res2->end ||
			    res1->end <= res2->start)
				continue;
			else if (res1->end <= res2->end &&
				 res1->start >= res2->start) {
				list_del(&res1->list);
				kfree(res1);
				break;
			} else if (res1->end > res2->end &&
				   res1->start < res2->start) {
				res = kmalloc(sizeof(*res), GFP_KERNEL);
				if (!res)
					return -ENOMEM;
				res->start = res2->end;
				res->end = res1->end;
				res1->end = res2->start;
				list_add(&res->list, &res1->list);
				resn1 = res;
			} else {
				if (res1->start < res2->start)
					res1->end = res2->start;
				else
					res1->start = res2->end;
			}
		}
		res1 = resn1;
		resn1 = list_entry(resn1->list.next, struct apei_res, list);
	}

	return 0;
}

static void apei_res_clean(struct list_head *res_list)
{
	struct apei_res *res, *resn;

	list_for_each_entry_safe(res, resn, res_list, list) {
		list_del(&res->list);
		kfree(res);
	}
}

void apei_resources_fini(struct apei_resources *resources)
{
	apei_res_clean(&resources->iomem);
	apei_res_clean(&resources->ioport);
}
EXPORT_SYMBOL_GPL(apei_resources_fini);

static int apei_resources_merge(struct apei_resources *resources1,
				struct apei_resources *resources2)
{
	int rc;
	struct apei_res *res;

	list_for_each_entry(res, &resources2->iomem, list) {
		rc = apei_res_add(&resources1->iomem, res->start,
				  res->end - res->start);
		if (rc)
			return rc;
	}
	list_for_each_entry(res, &resources2->ioport, list) {
		rc = apei_res_add(&resources1->ioport, res->start,
				  res->end - res->start);
		if (rc)
			return rc;
	}

	return 0;
}

int apei_resources_add(struct apei_resources *resources,
		       unsigned long start, unsigned long size,
		       bool iomem)
{
	if (iomem)
		return apei_res_add(&resources->iomem, start, size);
	else
		return apei_res_add(&resources->ioport, start, size);
}
EXPORT_SYMBOL_GPL(apei_resources_add);

/*
 * EINJ has two groups of GARs (EINJ table entry and trigger table
 * entry), so common resources are subtracted from the trigger table
 * resources before the second requesting.
 */
int apei_resources_sub(struct apei_resources *resources1,
		       struct apei_resources *resources2)
{
	int rc;

	rc = apei_res_sub(&resources1->iomem, &resources2->iomem);
	if (rc)
		return rc;
	return apei_res_sub(&resources1->ioport, &resources2->ioport);
}
EXPORT_SYMBOL_GPL(apei_resources_sub);

static int apei_get_res_callback(__u64 start, __u64 size, void *data)
{
	struct apei_resources *resources = data;
	return apei_res_add(&resources->iomem, start, size);
}

static int apei_get_nvs_resources(struct apei_resources *resources)
{
	return acpi_nvs_for_each_region(apei_get_res_callback, resources);
}

int (*arch_apei_filter_addr)(int (*func)(__u64 start, __u64 size,
				     void *data), void *data);
static int apei_get_arch_resources(struct apei_resources *resources)

{
	return arch_apei_filter_addr(apei_get_res_callback, resources);
}

/*
 * IO memory/port resource management mechanism is used to check
 * whether memory/port area used by GARs conflicts with normal memory
 * or IO memory/port of devices.
 */
int apei_resources_request(struct apei_resources *resources,
			   const char *desc)
{
	struct apei_res *res, *res_bak = NULL;
	struct resource *r;
	struct apei_resources nvs_resources, arch_res;
	int rc;

	rc = apei_resources_sub(resources, &apei_resources_all);
	if (rc)
		return rc;

	/*
	 * Some firmware uses ACPI NVS region, that has been marked as
	 * busy, so exclude it from APEI resources to avoid false
	 * conflict.
	 */
	apei_resources_init(&nvs_resources);
	rc = apei_get_nvs_resources(&nvs_resources);
	if (rc)
		goto nvs_res_fini;
	rc = apei_resources_sub(resources, &nvs_resources);
	if (rc)
		goto nvs_res_fini;

	if (arch_apei_filter_addr) {
		apei_resources_init(&arch_res);
		rc = apei_get_arch_resources(&arch_res);
		if (rc)
			goto arch_res_fini;
		rc = apei_resources_sub(resources, &arch_res);
		if (rc)
			goto arch_res_fini;
	}

	rc = -EINVAL;
	list_for_each_entry(res, &resources->iomem, list) {
		r = request_mem_region(res->start, res->end - res->start,
				       desc);
		if (!r) {
			pr_err(APEI_PFX
		"Can not request [mem %#010llx-%#010llx] for %s registers\n",
			       (unsigned long long)res->start,
			       (unsigned long long)res->end - 1, desc);
			res_bak = res;
			goto err_unmap_iomem;
		}
	}

	list_for_each_entry(res, &resources->ioport, list) {
		r = request_region(res->start, res->end - res->start, desc);
		if (!r) {
			pr_err(APEI_PFX
		"Can not request [io  %#06llx-%#06llx] for %s registers\n",
			       (unsigned long long)res->start,
			       (unsigned long long)res->end - 1, desc);
			res_bak = res;
			goto err_unmap_ioport;
		}
	}

	rc = apei_resources_merge(&apei_resources_all, resources);
	if (rc) {
		pr_err(APEI_PFX "Fail to merge resources!\n");
		goto err_unmap_ioport;
	}

	goto arch_res_fini;

err_unmap_ioport:
	list_for_each_entry(res, &resources->ioport, list) {
		if (res == res_bak)
			break;
		release_region(res->start, res->end - res->start);
	}
	res_bak = NULL;
err_unmap_iomem:
	list_for_each_entry(res, &resources->iomem, list) {
		if (res == res_bak)
			break;
		release_mem_region(res->start, res->end - res->start);
	}
arch_res_fini:
	if (arch_apei_filter_addr)
		apei_resources_fini(&arch_res);
nvs_res_fini:
	apei_resources_fini(&nvs_resources);
	return rc;
}
EXPORT_SYMBOL_GPL(apei_resources_request);

void apei_resources_release(struct apei_resources *resources)
{
	int rc;
	struct apei_res *res;

	list_for_each_entry(res, &resources->iomem, list)
		release_mem_region(res->start, res->end - res->start);
	list_for_each_entry(res, &resources->ioport, list)
		release_region(res->start, res->end - res->start);

	rc = apei_resources_sub(&apei_resources_all, resources);
	if (rc)
		pr_err(APEI_PFX "Fail to sub resources!\n");
}
EXPORT_SYMBOL_GPL(apei_resources_release);

static int apei_check_gar(struct acpi_generic_address *reg, u64 *paddr,
				u32 *access_bit_width)
{
	u32 bit_width, bit_offset, access_size_code, space_id;

	bit_width = reg->bit_width;
	bit_offset = reg->bit_offset;
	access_size_code = reg->access_width;
	space_id = reg->space_id;
	*paddr = get_unaligned(&reg->address);
	if (!*paddr) {
		pr_warning(FW_BUG APEI_PFX
			   "Invalid physical address in GAR [0x%llx/%u/%u/%u/%u]\n",
			   *paddr, bit_width, bit_offset, access_size_code,
			   space_id);
		return -EINVAL;
	}

	if (access_size_code < 1 || access_size_code > 4) {
		pr_warning(FW_BUG APEI_PFX
			   "Invalid access size code in GAR [0x%llx/%u/%u/%u/%u]\n",
			   *paddr, bit_width, bit_offset, access_size_code,
			   space_id);
		return -EINVAL;
	}
	*access_bit_width = 1UL << (access_size_code + 2);

	/* Fixup common BIOS bug */
	if (bit_width == 32 && bit_offset == 0 && (*paddr & 0x03) == 0 &&
	    *access_bit_width < 32)
		*access_bit_width = 32;
	else if (bit_width == 64 && bit_offset == 0 && (*paddr & 0x07) == 0 &&
	    *access_bit_width < 64)
		*access_bit_width = 64;

	if ((bit_width + bit_offset) > *access_bit_width) {
		pr_warning(FW_BUG APEI_PFX
			   "Invalid bit width + offset in GAR [0x%llx/%u/%u/%u/%u]\n",
			   *paddr, bit_width, bit_offset, access_size_code,
			   space_id);
		return -EINVAL;
	}

	if (space_id != ACPI_ADR_SPACE_SYSTEM_MEMORY &&
	    space_id != ACPI_ADR_SPACE_SYSTEM_IO) {
		pr_warning(FW_BUG APEI_PFX
			   "Invalid address space type in GAR [0x%llx/%u/%u/%u/%u]\n",
			   *paddr, bit_width, bit_offset, access_size_code,
			   space_id);
		return -EINVAL;
	}

	return 0;
}

int apei_map_generic_address(struct acpi_generic_address *reg)
{
	int rc;
	u32 access_bit_width;
	u64 address;

	rc = apei_check_gar(reg, &address, &access_bit_width);
	if (rc)
		return rc;
	return acpi_os_map_generic_address(reg);
}
EXPORT_SYMBOL_GPL(apei_map_generic_address);

/* read GAR in interrupt (including NMI) or process context */
int apei_read(u64 *val, struct acpi_generic_address *reg)
{
	int rc;
	u32 access_bit_width;
	u64 address;
	acpi_status status;

	rc = apei_check_gar(reg, &address, &access_bit_width);
	if (rc)
		return rc;

	*val = 0;
	switch(reg->space_id) {
	case ACPI_ADR_SPACE_SYSTEM_MEMORY:
		status = acpi_os_read_memory((acpi_physical_address) address,
					       val, access_bit_width);
		if (ACPI_FAILURE(status))
			return -EIO;
		break;
	case ACPI_ADR_SPACE_SYSTEM_IO:
		status = acpi_os_read_port(address, (u32 *)val,
					   access_bit_width);
		if (ACPI_FAILURE(status))
			return -EIO;
		break;
	default:
		return -EINVAL;
	}

	return 0;
}
EXPORT_SYMBOL_GPL(apei_read);

/* write GAR in interrupt (including NMI) or process context */
int apei_write(u64 val, struct acpi_generic_address *reg)
{
	int rc;
	u32 access_bit_width;
	u64 address;
	acpi_status status;

	rc = apei_check_gar(reg, &address, &access_bit_width);
	if (rc)
		return rc;

	switch (reg->space_id) {
	case ACPI_ADR_SPACE_SYSTEM_MEMORY:
		status = acpi_os_write_memory((acpi_physical_address) address,
						val, access_bit_width);
		if (ACPI_FAILURE(status))
			return -EIO;
		break;
	case ACPI_ADR_SPACE_SYSTEM_IO:
		status = acpi_os_write_port(address, val, access_bit_width);
		if (ACPI_FAILURE(status))
			return -EIO;
		break;
	default:
		return -EINVAL;
	}

	return 0;
}
EXPORT_SYMBOL_GPL(apei_write);

static int collect_res_callback(struct apei_exec_context *ctx,
				struct acpi_whea_header *entry,
				void *data)
{
	struct apei_resources *resources = data;
	struct acpi_generic_address *reg = &entry->register_region;
	u8 ins = entry->instruction;
	u32 access_bit_width;
	u64 paddr;
	int rc;

	if (!(ctx->ins_table[ins].flags & APEI_EXEC_INS_ACCESS_REGISTER))
		return 0;

	rc = apei_check_gar(reg, &paddr, &access_bit_width);
	if (rc)
		return rc;

	switch (reg->space_id) {
	case ACPI_ADR_SPACE_SYSTEM_MEMORY:
		return apei_res_add(&resources->iomem, paddr,
				    access_bit_width / 8);
	case ACPI_ADR_SPACE_SYSTEM_IO:
		return apei_res_add(&resources->ioport, paddr,
				    access_bit_width / 8);
	default:
		return -EINVAL;
	}
}

/*
 * Same register may be used by multiple instructions in GARs, so
 * resources are collected before requesting.
 */
int apei_exec_collect_resources(struct apei_exec_context *ctx,
				struct apei_resources *resources)
{
	return apei_exec_for_each_entry(ctx, collect_res_callback,
					resources, NULL);
}
EXPORT_SYMBOL_GPL(apei_exec_collect_resources);

struct dentry *apei_get_debugfs_dir(void)
{
	static struct dentry *dapei;

	if (!dapei)
		dapei = debugfs_create_dir("apei", NULL);

	return dapei;
}
EXPORT_SYMBOL_GPL(apei_get_debugfs_dir);

int __weak arch_apei_enable_cmcff(struct acpi_hest_header *hest_hdr,
				  void *data)
{
	return 1;
}
EXPORT_SYMBOL_GPL(arch_apei_enable_cmcff);

void __weak arch_apei_report_mem_error(int sev,
				       struct cper_sec_mem_err *mem_err)
{
}
EXPORT_SYMBOL_GPL(arch_apei_report_mem_error);

int apei_osc_setup(void)
{
	static u8 whea_uuid_str[] = "ed855e0c-6c90-47bf-a62a-26de0fc5ad5c";
	acpi_handle handle;
	u32 capbuf[3];
	struct acpi_osc_context context = {
		.uuid_str	= whea_uuid_str,
		.rev		= 1,
		.cap.length	= sizeof(capbuf),
		.cap.pointer	= capbuf,
	};

	capbuf[OSC_QUERY_DWORD] = OSC_QUERY_ENABLE;
	capbuf[OSC_SUPPORT_DWORD] = 1;
	capbuf[OSC_CONTROL_DWORD] = 0;

	if (ACPI_FAILURE(acpi_get_handle(NULL, "\\_SB", &handle))
	    || ACPI_FAILURE(acpi_run_osc(handle, &context)))
		return -EIO;
	else {
		kfree(context.ret.pointer);
		return 0;
	}
}
EXPORT_SYMBOL_GPL(apei_osc_setup);