summaryrefslogtreecommitdiff
path: root/arch/arm64/kvm/sys_regs.c
blob: 03244582bc555af4b303fca4370890e278114d16 (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
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
/*
 * Copyright (C) 2012,2013 - ARM Ltd
 * Author: Marc Zyngier <marc.zyngier@arm.com>
 *
 * Derived from arch/arm/kvm/coproc.c:
 * Copyright (C) 2012 - Virtual Open Systems and Columbia University
 * Authors: Rusty Russell <rusty@rustcorp.com.au>
 *          Christoffer Dall <c.dall@virtualopensystems.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License, version 2, as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <linux/mm.h>
#include <linux/kvm_host.h>
#include <linux/uaccess.h>
#include <asm/kvm_arm.h>
#include <asm/kvm_host.h>
#include <asm/kvm_emulate.h>
#include <asm/kvm_coproc.h>
#include <asm/kvm_mmu.h>
#include <asm/cacheflush.h>
#include <asm/cputype.h>
#include <trace/events/kvm.h>

#include "sys_regs.h"

/*
 * All of this file is extremly similar to the ARM coproc.c, but the
 * types are different. My gut feeling is that it should be pretty
 * easy to merge, but that would be an ABI breakage -- again. VFP
 * would also need to be abstracted.
 *
 * For AArch32, we only take care of what is being trapped. Anything
 * that has to do with init and userspace access has to go via the
 * 64bit interface.
 */

/* 3 bits per cache level, as per CLIDR, but non-existent caches always 0 */
static u32 cache_levels;

/* CSSELR values; used to index KVM_REG_ARM_DEMUX_ID_CCSIDR */
#define CSSELR_MAX 12

/* Which cache CCSIDR represents depends on CSSELR value. */
static u32 get_ccsidr(u32 csselr)
{
	u32 ccsidr;

	/* Make sure noone else changes CSSELR during this! */
	local_irq_disable();
	/* Put value into CSSELR */
	asm volatile("msr csselr_el1, %x0" : : "r" (csselr));
	isb();
	/* Read result out of CCSIDR */
	asm volatile("mrs %0, ccsidr_el1" : "=r" (ccsidr));
	local_irq_enable();

	return ccsidr;
}

static void do_dc_cisw(u32 val)
{
	asm volatile("dc cisw, %x0" : : "r" (val));
	dsb();
}

static void do_dc_csw(u32 val)
{
	asm volatile("dc csw, %x0" : : "r" (val));
	dsb();
}

/* See note at ARM ARM B1.14.4 */
static bool access_dcsw(struct kvm_vcpu *vcpu,
			const struct sys_reg_params *p,
			const struct sys_reg_desc *r)
{
	unsigned long val;
	int cpu;

	if (!p->is_write)
		return read_from_write_only(vcpu, p);

	cpu = get_cpu();

	cpumask_setall(&vcpu->arch.require_dcache_flush);
	cpumask_clear_cpu(cpu, &vcpu->arch.require_dcache_flush);

	/* If we were already preempted, take the long way around */
	if (cpu != vcpu->arch.last_pcpu) {
		flush_cache_all();
		goto done;
	}

	val = *vcpu_reg(vcpu, p->Rt);

	switch (p->CRm) {
	case 6:			/* Upgrade DCISW to DCCISW, as per HCR.SWIO */
	case 14:		/* DCCISW */
		do_dc_cisw(val);
		break;

	case 10:		/* DCCSW */
		do_dc_csw(val);
		break;
	}

done:
	put_cpu();

	return true;
}

/*
 * Generic accessor for VM registers. Only called as long as HCR_TVM
 * is set.
 */
static bool access_vm_reg(struct kvm_vcpu *vcpu,
			  const struct sys_reg_params *p,
			  const struct sys_reg_desc *r)
{
	unsigned long val;

	BUG_ON(!p->is_write);

	val = *vcpu_reg(vcpu, p->Rt);
	if (!p->is_aarch32) {
		vcpu_sys_reg(vcpu, r->reg) = val;
	} else {
		vcpu_cp15(vcpu, r->reg) = val & 0xffffffffUL;
		if (!p->is_32bit)
			vcpu_cp15(vcpu, r->reg + 1) = val >> 32;
	}
	return true;
}

/*
 * SCTLR_EL1 accessor. Only called as long as HCR_TVM is set.  If the
 * guest enables the MMU, we stop trapping the VM sys_regs and leave
 * it in complete control of the caches.
 */
static bool access_sctlr(struct kvm_vcpu *vcpu,
			 const struct sys_reg_params *p,
			 const struct sys_reg_desc *r)
{
	access_vm_reg(vcpu, p, r);

	if (vcpu_has_cache_enabled(vcpu)) {	/* MMU+Caches enabled? */
		vcpu->arch.hcr_el2 &= ~HCR_TVM;
		stage2_flush_vm(vcpu->kvm);
	}

	return true;
}

/*
 * We could trap ID_DFR0 and tell the guest we don't support performance
 * monitoring.  Unfortunately the patch to make the kernel check ID_DFR0 was
 * NAKed, so it will read the PMCR anyway.
 *
 * Therefore we tell the guest we have 0 counters.  Unfortunately, we
 * must always support PMCCNTR (the cycle counter): we just RAZ/WI for
 * all PM registers, which doesn't crash the guest kernel at least.
 */
static bool pm_fake(struct kvm_vcpu *vcpu,
		    const struct sys_reg_params *p,
		    const struct sys_reg_desc *r)
{
	if (p->is_write)
		return ignore_write(vcpu, p);
	else
		return read_zero(vcpu, p);
}

static void reset_amair_el1(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r)
{
	u64 amair;

	asm volatile("mrs %0, amair_el1\n" : "=r" (amair));
	vcpu_sys_reg(vcpu, AMAIR_EL1) = amair;
}

static void reset_mpidr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r)
{
	/*
	 * Simply map the vcpu_id into the Aff0 field of the MPIDR.
	 */
	vcpu_sys_reg(vcpu, MPIDR_EL1) = (1UL << 31) | (vcpu->vcpu_id & 0xff);
}

/*
 * Architected system registers.
 * Important: Must be sorted ascending by Op0, Op1, CRn, CRm, Op2
 */
static const struct sys_reg_desc sys_reg_descs[] = {
	/* DC ISW */
	{ Op0(0b01), Op1(0b000), CRn(0b0111), CRm(0b0110), Op2(0b010),
	  access_dcsw },
	/* DC CSW */
	{ Op0(0b01), Op1(0b000), CRn(0b0111), CRm(0b1010), Op2(0b010),
	  access_dcsw },
	/* DC CISW */
	{ Op0(0b01), Op1(0b000), CRn(0b0111), CRm(0b1110), Op2(0b010),
	  access_dcsw },

	/* TEECR32_EL1 */
	{ Op0(0b10), Op1(0b010), CRn(0b0000), CRm(0b0000), Op2(0b000),
	  NULL, reset_val, TEECR32_EL1, 0 },
	/* TEEHBR32_EL1 */
	{ Op0(0b10), Op1(0b010), CRn(0b0001), CRm(0b0000), Op2(0b000),
	  NULL, reset_val, TEEHBR32_EL1, 0 },
	/* DBGVCR32_EL2 */
	{ Op0(0b10), Op1(0b100), CRn(0b0000), CRm(0b0111), Op2(0b000),
	  NULL, reset_val, DBGVCR32_EL2, 0 },

	/* MPIDR_EL1 */
	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0000), Op2(0b101),
	  NULL, reset_mpidr, MPIDR_EL1 },
	/* SCTLR_EL1 */
	{ Op0(0b11), Op1(0b000), CRn(0b0001), CRm(0b0000), Op2(0b000),
	  access_sctlr, reset_val, SCTLR_EL1, 0x00C50078 },
	/* CPACR_EL1 */
	{ Op0(0b11), Op1(0b000), CRn(0b0001), CRm(0b0000), Op2(0b010),
	  NULL, reset_val, CPACR_EL1, 0 },
	/* TTBR0_EL1 */
	{ Op0(0b11), Op1(0b000), CRn(0b0010), CRm(0b0000), Op2(0b000),
	  access_vm_reg, reset_unknown, TTBR0_EL1 },
	/* TTBR1_EL1 */
	{ Op0(0b11), Op1(0b000), CRn(0b0010), CRm(0b0000), Op2(0b001),
	  access_vm_reg, reset_unknown, TTBR1_EL1 },
	/* TCR_EL1 */
	{ Op0(0b11), Op1(0b000), CRn(0b0010), CRm(0b0000), Op2(0b010),
	  access_vm_reg, reset_val, TCR_EL1, 0 },

	/* AFSR0_EL1 */
	{ Op0(0b11), Op1(0b000), CRn(0b0101), CRm(0b0001), Op2(0b000),
	  access_vm_reg, reset_unknown, AFSR0_EL1 },
	/* AFSR1_EL1 */
	{ Op0(0b11), Op1(0b000), CRn(0b0101), CRm(0b0001), Op2(0b001),
	  access_vm_reg, reset_unknown, AFSR1_EL1 },
	/* ESR_EL1 */
	{ Op0(0b11), Op1(0b000), CRn(0b0101), CRm(0b0010), Op2(0b000),
	  access_vm_reg, reset_unknown, ESR_EL1 },
	/* FAR_EL1 */
	{ Op0(0b11), Op1(0b000), CRn(0b0110), CRm(0b0000), Op2(0b000),
	  access_vm_reg, reset_unknown, FAR_EL1 },
	/* PAR_EL1 */
	{ Op0(0b11), Op1(0b000), CRn(0b0111), CRm(0b0100), Op2(0b000),
	  NULL, reset_unknown, PAR_EL1 },

	/* PMINTENSET_EL1 */
	{ Op0(0b11), Op1(0b000), CRn(0b1001), CRm(0b1110), Op2(0b001),
	  pm_fake },
	/* PMINTENCLR_EL1 */
	{ Op0(0b11), Op1(0b000), CRn(0b1001), CRm(0b1110), Op2(0b010),
	  pm_fake },

	/* MAIR_EL1 */
	{ Op0(0b11), Op1(0b000), CRn(0b1010), CRm(0b0010), Op2(0b000),
	  access_vm_reg, reset_unknown, MAIR_EL1 },
	/* AMAIR_EL1 */
	{ Op0(0b11), Op1(0b000), CRn(0b1010), CRm(0b0011), Op2(0b000),
	  access_vm_reg, reset_amair_el1, AMAIR_EL1 },

	/* VBAR_EL1 */
	{ Op0(0b11), Op1(0b000), CRn(0b1100), CRm(0b0000), Op2(0b000),
	  NULL, reset_val, VBAR_EL1, 0 },
	/* CONTEXTIDR_EL1 */
	{ Op0(0b11), Op1(0b000), CRn(0b1101), CRm(0b0000), Op2(0b001),
	  access_vm_reg, reset_val, CONTEXTIDR_EL1, 0 },
	/* TPIDR_EL1 */
	{ Op0(0b11), Op1(0b000), CRn(0b1101), CRm(0b0000), Op2(0b100),
	  NULL, reset_unknown, TPIDR_EL1 },

	/* CNTKCTL_EL1 */
	{ Op0(0b11), Op1(0b000), CRn(0b1110), CRm(0b0001), Op2(0b000),
	  NULL, reset_val, CNTKCTL_EL1, 0},

	/* CSSELR_EL1 */
	{ Op0(0b11), Op1(0b010), CRn(0b0000), CRm(0b0000), Op2(0b000),
	  NULL, reset_unknown, CSSELR_EL1 },

	/* PMCR_EL0 */
	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1100), Op2(0b000),
	  pm_fake },
	/* PMCNTENSET_EL0 */
	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1100), Op2(0b001),
	  pm_fake },
	/* PMCNTENCLR_EL0 */
	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1100), Op2(0b010),
	  pm_fake },
	/* PMOVSCLR_EL0 */
	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1100), Op2(0b011),
	  pm_fake },
	/* PMSWINC_EL0 */
	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1100), Op2(0b100),
	  pm_fake },
	/* PMSELR_EL0 */
	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1100), Op2(0b101),
	  pm_fake },
	/* PMCEID0_EL0 */
	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1100), Op2(0b110),
	  pm_fake },
	/* PMCEID1_EL0 */
	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1100), Op2(0b111),
	  pm_fake },
	/* PMCCNTR_EL0 */
	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1101), Op2(0b000),
	  pm_fake },
	/* PMXEVTYPER_EL0 */
	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1101), Op2(0b001),
	  pm_fake },
	/* PMXEVCNTR_EL0 */
	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1101), Op2(0b010),
	  pm_fake },
	/* PMUSERENR_EL0 */
	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1110), Op2(0b000),
	  pm_fake },
	/* PMOVSSET_EL0 */
	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1110), Op2(0b011),
	  pm_fake },

	/* TPIDR_EL0 */
	{ Op0(0b11), Op1(0b011), CRn(0b1101), CRm(0b0000), Op2(0b010),
	  NULL, reset_unknown, TPIDR_EL0 },
	/* TPIDRRO_EL0 */
	{ Op0(0b11), Op1(0b011), CRn(0b1101), CRm(0b0000), Op2(0b011),
	  NULL, reset_unknown, TPIDRRO_EL0 },

	/* DACR32_EL2 */
	{ Op0(0b11), Op1(0b100), CRn(0b0011), CRm(0b0000), Op2(0b000),
	  NULL, reset_unknown, DACR32_EL2 },
	/* IFSR32_EL2 */
	{ Op0(0b11), Op1(0b100), CRn(0b0101), CRm(0b0000), Op2(0b001),
	  NULL, reset_unknown, IFSR32_EL2 },
	/* FPEXC32_EL2 */
	{ Op0(0b11), Op1(0b100), CRn(0b0101), CRm(0b0011), Op2(0b000),
	  NULL, reset_val, FPEXC32_EL2, 0x70 },
};

/*
 * Trapped cp15 registers. TTBR0/TTBR1 get a double encoding,
 * depending on the way they are accessed (as a 32bit or a 64bit
 * register).
 */
static const struct sys_reg_desc cp15_regs[] = {
	{ Op1( 0), CRn( 0), CRm( 2), Op2( 0), access_vm_reg, NULL, c2_TTBR0 },
	{ Op1( 0), CRn( 1), CRm( 0), Op2( 0), access_sctlr, NULL, c1_SCTLR },
	{ Op1( 0), CRn( 2), CRm( 0), Op2( 0), access_vm_reg, NULL, c2_TTBR0 },
	{ Op1( 0), CRn( 2), CRm( 0), Op2( 1), access_vm_reg, NULL, c2_TTBR1 },
	{ Op1( 0), CRn( 2), CRm( 0), Op2( 2), access_vm_reg, NULL, c2_TTBCR },
	{ Op1( 0), CRn( 3), CRm( 0), Op2( 0), access_vm_reg, NULL, c3_DACR },
	{ Op1( 0), CRn( 5), CRm( 0), Op2( 0), access_vm_reg, NULL, c5_DFSR },
	{ Op1( 0), CRn( 5), CRm( 0), Op2( 1), access_vm_reg, NULL, c5_IFSR },
	{ Op1( 0), CRn( 5), CRm( 1), Op2( 0), access_vm_reg, NULL, c5_ADFSR },
	{ Op1( 0), CRn( 5), CRm( 1), Op2( 1), access_vm_reg, NULL, c5_AIFSR },
	{ Op1( 0), CRn( 6), CRm( 0), Op2( 0), access_vm_reg, NULL, c6_DFAR },
	{ Op1( 0), CRn( 6), CRm( 0), Op2( 2), access_vm_reg, NULL, c6_IFAR },

	/*
	 * DC{C,I,CI}SW operations:
	 */
	{ Op1( 0), CRn( 7), CRm( 6), Op2( 2), access_dcsw },
	{ Op1( 0), CRn( 7), CRm(10), Op2( 2), access_dcsw },
	{ Op1( 0), CRn( 7), CRm(14), Op2( 2), access_dcsw },

	{ Op1( 0), CRn( 9), CRm(12), Op2( 0), pm_fake },
	{ Op1( 0), CRn( 9), CRm(12), Op2( 1), pm_fake },
	{ Op1( 0), CRn( 9), CRm(12), Op2( 2), pm_fake },
	{ Op1( 0), CRn( 9), CRm(12), Op2( 3), pm_fake },
	{ Op1( 0), CRn( 9), CRm(12), Op2( 5), pm_fake },
	{ Op1( 0), CRn( 9), CRm(12), Op2( 6), pm_fake },
	{ Op1( 0), CRn( 9), CRm(12), Op2( 7), pm_fake },
	{ Op1( 0), CRn( 9), CRm(13), Op2( 0), pm_fake },
	{ Op1( 0), CRn( 9), CRm(13), Op2( 1), pm_fake },
	{ Op1( 0), CRn( 9), CRm(13), Op2( 2), pm_fake },
	{ Op1( 0), CRn( 9), CRm(14), Op2( 0), pm_fake },
	{ Op1( 0), CRn( 9), CRm(14), Op2( 1), pm_fake },
	{ Op1( 0), CRn( 9), CRm(14), Op2( 2), pm_fake },

	{ Op1( 0), CRn(10), CRm( 2), Op2( 0), access_vm_reg, NULL, c10_PRRR },
	{ Op1( 0), CRn(10), CRm( 2), Op2( 1), access_vm_reg, NULL, c10_NMRR },
	{ Op1( 0), CRn(10), CRm( 3), Op2( 0), access_vm_reg, NULL, c10_AMAIR0 },
	{ Op1( 0), CRn(10), CRm( 3), Op2( 1), access_vm_reg, NULL, c10_AMAIR1 },
	{ Op1( 0), CRn(13), CRm( 0), Op2( 1), access_vm_reg, NULL, c13_CID },

	{ Op1( 1), CRn( 0), CRm( 2), Op2( 0), access_vm_reg, NULL, c2_TTBR1 },
};

/* Target specific emulation tables */
static struct kvm_sys_reg_target_table *target_tables[KVM_ARM_NUM_TARGETS];

void kvm_register_target_sys_reg_table(unsigned int target,
				       struct kvm_sys_reg_target_table *table)
{
	target_tables[target] = table;
}

/* Get specific register table for this target. */
static const struct sys_reg_desc *get_target_table(unsigned target,
						   bool mode_is_64,
						   size_t *num)
{
	struct kvm_sys_reg_target_table *table;

	table = target_tables[target];
	if (mode_is_64) {
		*num = table->table64.num;
		return table->table64.table;
	} else {
		*num = table->table32.num;
		return table->table32.table;
	}
}

static const struct sys_reg_desc *find_reg(const struct sys_reg_params *params,
					 const struct sys_reg_desc table[],
					 unsigned int num)
{
	unsigned int i;

	for (i = 0; i < num; i++) {
		const struct sys_reg_desc *r = &table[i];

		if (params->Op0 != r->Op0)
			continue;
		if (params->Op1 != r->Op1)
			continue;
		if (params->CRn != r->CRn)
			continue;
		if (params->CRm != r->CRm)
			continue;
		if (params->Op2 != r->Op2)
			continue;

		return r;
	}
	return NULL;
}

int kvm_handle_cp14_load_store(struct kvm_vcpu *vcpu, struct kvm_run *run)
{
	kvm_inject_undefined(vcpu);
	return 1;
}

int kvm_handle_cp14_access(struct kvm_vcpu *vcpu, struct kvm_run *run)
{
	kvm_inject_undefined(vcpu);
	return 1;
}

static void emulate_cp15(struct kvm_vcpu *vcpu,
			 const struct sys_reg_params *params)
{
	size_t num;
	const struct sys_reg_desc *table, *r;

	table = get_target_table(vcpu->arch.target, false, &num);

	/* Search target-specific then generic table. */
	r = find_reg(params, table, num);
	if (!r)
		r = find_reg(params, cp15_regs, ARRAY_SIZE(cp15_regs));

	if (likely(r)) {
		/*
		 * Not having an accessor means that we have
		 * configured a trap that we don't know how to
		 * handle. This certainly qualifies as a gross bug
		 * that should be fixed right away.
		 */
		BUG_ON(!r->access);

		if (likely(r->access(vcpu, params, r))) {
			/* Skip instruction, since it was emulated */
			kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu));
			return;
		}
		/* If access function fails, it should complain. */
	}

	kvm_err("Unsupported guest CP15 access at: %08lx\n", *vcpu_pc(vcpu));
	print_sys_reg_instr(params);
	kvm_inject_undefined(vcpu);
}

/**
 * kvm_handle_cp15_64 -- handles a mrrc/mcrr trap on a guest CP15 access
 * @vcpu: The VCPU pointer
 * @run:  The kvm_run struct
 */
int kvm_handle_cp15_64(struct kvm_vcpu *vcpu, struct kvm_run *run)
{
	struct sys_reg_params params;
	u32 hsr = kvm_vcpu_get_hsr(vcpu);
	int Rt2 = (hsr >> 10) & 0xf;

	params.is_aarch32 = true;
	params.is_32bit = false;
	params.CRm = (hsr >> 1) & 0xf;
	params.Rt = (hsr >> 5) & 0xf;
	params.is_write = ((hsr & 1) == 0);

	params.Op0 = 0;
	params.Op1 = (hsr >> 16) & 0xf;
	params.Op2 = 0;
	params.CRn = 0;

	/*
	 * Massive hack here. Store Rt2 in the top 32bits so we only
	 * have one register to deal with. As we use the same trap
	 * backends between AArch32 and AArch64, we get away with it.
	 */
	if (params.is_write) {
		u64 val = *vcpu_reg(vcpu, params.Rt);
		val &= 0xffffffff;
		val |= *vcpu_reg(vcpu, Rt2) << 32;
		*vcpu_reg(vcpu, params.Rt) = val;
	}

	emulate_cp15(vcpu, &params);

	/* Do the opposite hack for the read side */
	if (!params.is_write) {
		u64 val = *vcpu_reg(vcpu, params.Rt);
		val >>= 32;
		*vcpu_reg(vcpu, Rt2) = val;
	}

	return 1;
}

/**
 * kvm_handle_cp15_32 -- handles a mrc/mcr trap on a guest CP15 access
 * @vcpu: The VCPU pointer
 * @run:  The kvm_run struct
 */
int kvm_handle_cp15_32(struct kvm_vcpu *vcpu, struct kvm_run *run)
{
	struct sys_reg_params params;
	u32 hsr = kvm_vcpu_get_hsr(vcpu);

	params.is_aarch32 = true;
	params.is_32bit = true;
	params.CRm = (hsr >> 1) & 0xf;
	params.Rt  = (hsr >> 5) & 0xf;
	params.is_write = ((hsr & 1) == 0);
	params.CRn = (hsr >> 10) & 0xf;
	params.Op0 = 0;
	params.Op1 = (hsr >> 14) & 0x7;
	params.Op2 = (hsr >> 17) & 0x7;

	emulate_cp15(vcpu, &params);
	return 1;
}

static int emulate_sys_reg(struct kvm_vcpu *vcpu,
			   const struct sys_reg_params *params)
{
	size_t num;
	const struct sys_reg_desc *table, *r;

	table = get_target_table(vcpu->arch.target, true, &num);

	/* Search target-specific then generic table. */
	r = find_reg(params, table, num);
	if (!r)
		r = find_reg(params, sys_reg_descs, ARRAY_SIZE(sys_reg_descs));

	if (likely(r)) {
		/*
		 * Not having an accessor means that we have
		 * configured a trap that we don't know how to
		 * handle. This certainly qualifies as a gross bug
		 * that should be fixed right away.
		 */
		BUG_ON(!r->access);

		if (likely(r->access(vcpu, params, r))) {
			/* Skip instruction, since it was emulated */
			kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu));
			return 1;
		}
		/* If access function fails, it should complain. */
	} else {
		kvm_err("Unsupported guest sys_reg access at: %lx\n",
			*vcpu_pc(vcpu));
		print_sys_reg_instr(params);
	}
	kvm_inject_undefined(vcpu);
	return 1;
}

static void reset_sys_reg_descs(struct kvm_vcpu *vcpu,
			      const struct sys_reg_desc *table, size_t num)
{
	unsigned long i;

	for (i = 0; i < num; i++)
		if (table[i].reset)
			table[i].reset(vcpu, &table[i]);
}

/**
 * kvm_handle_sys_reg -- handles a mrs/msr trap on a guest sys_reg access
 * @vcpu: The VCPU pointer
 * @run:  The kvm_run struct
 */
int kvm_handle_sys_reg(struct kvm_vcpu *vcpu, struct kvm_run *run)
{
	struct sys_reg_params params;
	unsigned long esr = kvm_vcpu_get_hsr(vcpu);

	params.is_aarch32 = false;
	params.is_32bit = false;
	params.Op0 = (esr >> 20) & 3;
	params.Op1 = (esr >> 14) & 0x7;
	params.CRn = (esr >> 10) & 0xf;
	params.CRm = (esr >> 1) & 0xf;
	params.Op2 = (esr >> 17) & 0x7;
	params.Rt = (esr >> 5) & 0x1f;
	params.is_write = !(esr & 1);

	return emulate_sys_reg(vcpu, &params);
}

/******************************************************************************
 * Userspace API
 *****************************************************************************/

static bool index_to_params(u64 id, struct sys_reg_params *params)
{
	switch (id & KVM_REG_SIZE_MASK) {
	case KVM_REG_SIZE_U64:
		/* Any unused index bits means it's not valid. */
		if (id & ~(KVM_REG_ARCH_MASK | KVM_REG_SIZE_MASK
			      | KVM_REG_ARM_COPROC_MASK
			      | KVM_REG_ARM64_SYSREG_OP0_MASK
			      | KVM_REG_ARM64_SYSREG_OP1_MASK
			      | KVM_REG_ARM64_SYSREG_CRN_MASK
			      | KVM_REG_ARM64_SYSREG_CRM_MASK
			      | KVM_REG_ARM64_SYSREG_OP2_MASK))
			return false;
		params->Op0 = ((id & KVM_REG_ARM64_SYSREG_OP0_MASK)
			       >> KVM_REG_ARM64_SYSREG_OP0_SHIFT);
		params->Op1 = ((id & KVM_REG_ARM64_SYSREG_OP1_MASK)
			       >> KVM_REG_ARM64_SYSREG_OP1_SHIFT);
		params->CRn = ((id & KVM_REG_ARM64_SYSREG_CRN_MASK)
			       >> KVM_REG_ARM64_SYSREG_CRN_SHIFT);
		params->CRm = ((id & KVM_REG_ARM64_SYSREG_CRM_MASK)
			       >> KVM_REG_ARM64_SYSREG_CRM_SHIFT);
		params->Op2 = ((id & KVM_REG_ARM64_SYSREG_OP2_MASK)
			       >> KVM_REG_ARM64_SYSREG_OP2_SHIFT);
		return true;
	default:
		return false;
	}
}

/* Decode an index value, and find the sys_reg_desc entry. */
static const struct sys_reg_desc *index_to_sys_reg_desc(struct kvm_vcpu *vcpu,
						    u64 id)
{
	size_t num;
	const struct sys_reg_desc *table, *r;
	struct sys_reg_params params;

	/* We only do sys_reg for now. */
	if ((id & KVM_REG_ARM_COPROC_MASK) != KVM_REG_ARM64_SYSREG)
		return NULL;

	if (!index_to_params(id, &params))
		return NULL;

	table = get_target_table(vcpu->arch.target, true, &num);
	r = find_reg(&params, table, num);
	if (!r)
		r = find_reg(&params, sys_reg_descs, ARRAY_SIZE(sys_reg_descs));

	/* Not saved in the sys_reg array? */
	if (r && !r->reg)
		r = NULL;

	return r;
}

/*
 * These are the invariant sys_reg registers: we let the guest see the
 * host versions of these, so they're part of the guest state.
 *
 * A future CPU may provide a mechanism to present different values to
 * the guest, or a future kvm may trap them.
 */

#define FUNCTION_INVARIANT(reg)						\
	static void get_##reg(struct kvm_vcpu *v,			\
			      const struct sys_reg_desc *r)		\
	{								\
		u64 val;						\
									\
		asm volatile("mrs %0, " __stringify(reg) "\n"		\
			     : "=r" (val));				\
		((struct sys_reg_desc *)r)->val = val;			\
	}

FUNCTION_INVARIANT(midr_el1)
FUNCTION_INVARIANT(ctr_el0)
FUNCTION_INVARIANT(revidr_el1)
FUNCTION_INVARIANT(id_pfr0_el1)
FUNCTION_INVARIANT(id_pfr1_el1)
FUNCTION_INVARIANT(id_dfr0_el1)
FUNCTION_INVARIANT(id_afr0_el1)
FUNCTION_INVARIANT(id_mmfr0_el1)
FUNCTION_INVARIANT(id_mmfr1_el1)
FUNCTION_INVARIANT(id_mmfr2_el1)
FUNCTION_INVARIANT(id_mmfr3_el1)
FUNCTION_INVARIANT(id_isar0_el1)
FUNCTION_INVARIANT(id_isar1_el1)
FUNCTION_INVARIANT(id_isar2_el1)
FUNCTION_INVARIANT(id_isar3_el1)
FUNCTION_INVARIANT(id_isar4_el1)
FUNCTION_INVARIANT(id_isar5_el1)
FUNCTION_INVARIANT(clidr_el1)
FUNCTION_INVARIANT(aidr_el1)

/* ->val is filled in by kvm_sys_reg_table_init() */
static struct sys_reg_desc invariant_sys_regs[] = {
	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0000), Op2(0b000),
	  NULL, get_midr_el1 },
	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0000), Op2(0b110),
	  NULL, get_revidr_el1 },
	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0001), Op2(0b000),
	  NULL, get_id_pfr0_el1 },
	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0001), Op2(0b001),
	  NULL, get_id_pfr1_el1 },
	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0001), Op2(0b010),
	  NULL, get_id_dfr0_el1 },
	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0001), Op2(0b011),
	  NULL, get_id_afr0_el1 },
	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0001), Op2(0b100),
	  NULL, get_id_mmfr0_el1 },
	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0001), Op2(0b101),
	  NULL, get_id_mmfr1_el1 },
	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0001), Op2(0b110),
	  NULL, get_id_mmfr2_el1 },
	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0001), Op2(0b111),
	  NULL, get_id_mmfr3_el1 },
	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0010), Op2(0b000),
	  NULL, get_id_isar0_el1 },
	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0010), Op2(0b001),
	  NULL, get_id_isar1_el1 },
	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0010), Op2(0b010),
	  NULL, get_id_isar2_el1 },
	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0010), Op2(0b011),
	  NULL, get_id_isar3_el1 },
	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0010), Op2(0b100),
	  NULL, get_id_isar4_el1 },
	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0010), Op2(0b101),
	  NULL, get_id_isar5_el1 },
	{ Op0(0b11), Op1(0b001), CRn(0b0000), CRm(0b0000), Op2(0b001),
	  NULL, get_clidr_el1 },
	{ Op0(0b11), Op1(0b001), CRn(0b0000), CRm(0b0000), Op2(0b111),
	  NULL, get_aidr_el1 },
	{ Op0(0b11), Op1(0b011), CRn(0b0000), CRm(0b0000), Op2(0b001),
	  NULL, get_ctr_el0 },
};

static int reg_from_user(void *val, const void __user *uaddr, u64 id)
{
	/* This Just Works because we are little endian. */
	if (copy_from_user(val, uaddr, KVM_REG_SIZE(id)) != 0)
		return -EFAULT;
	return 0;
}

static int reg_to_user(void __user *uaddr, const void *val, u64 id)
{
	/* This Just Works because we are little endian. */
	if (copy_to_user(uaddr, val, KVM_REG_SIZE(id)) != 0)
		return -EFAULT;
	return 0;
}

static int get_invariant_sys_reg(u64 id, void __user *uaddr)
{
	struct sys_reg_params params;
	const struct sys_reg_desc *r;

	if (!index_to_params(id, &params))
		return -ENOENT;

	r = find_reg(&params, invariant_sys_regs, ARRAY_SIZE(invariant_sys_regs));
	if (!r)
		return -ENOENT;

	return reg_to_user(uaddr, &r->val, id);
}

static int set_invariant_sys_reg(u64 id, void __user *uaddr)
{
	struct sys_reg_params params;
	const struct sys_reg_desc *r;
	int err;
	u64 val = 0; /* Make sure high bits are 0 for 32-bit regs */

	if (!index_to_params(id, &params))
		return -ENOENT;
	r = find_reg(&params, invariant_sys_regs, ARRAY_SIZE(invariant_sys_regs));
	if (!r)
		return -ENOENT;

	err = reg_from_user(&val, uaddr, id);
	if (err)
		return err;

	/* This is what we mean by invariant: you can't change it. */
	if (r->val != val)
		return -EINVAL;

	return 0;
}

static bool is_valid_cache(u32 val)
{
	u32 level, ctype;

	if (val >= CSSELR_MAX)
		return -ENOENT;

	/* Bottom bit is Instruction or Data bit.  Next 3 bits are level. */
	level = (val >> 1);
	ctype = (cache_levels >> (level * 3)) & 7;

	switch (ctype) {
	case 0: /* No cache */
		return false;
	case 1: /* Instruction cache only */
		return (val & 1);
	case 2: /* Data cache only */
	case 4: /* Unified cache */
		return !(val & 1);
	case 3: /* Separate instruction and data caches */
		return true;
	default: /* Reserved: we can't know instruction or data. */
		return false;
	}
}

static int demux_c15_get(u64 id, void __user *uaddr)
{
	u32 val;
	u32 __user *uval = uaddr;

	/* Fail if we have unknown bits set. */
	if (id & ~(KVM_REG_ARCH_MASK|KVM_REG_SIZE_MASK|KVM_REG_ARM_COPROC_MASK
		   | ((1 << KVM_REG_ARM_COPROC_SHIFT)-1)))
		return -ENOENT;

	switch (id & KVM_REG_ARM_DEMUX_ID_MASK) {
	case KVM_REG_ARM_DEMUX_ID_CCSIDR:
		if (KVM_REG_SIZE(id) != 4)
			return -ENOENT;
		val = (id & KVM_REG_ARM_DEMUX_VAL_MASK)
			>> KVM_REG_ARM_DEMUX_VAL_SHIFT;
		if (!is_valid_cache(val))
			return -ENOENT;

		return put_user(get_ccsidr(val), uval);
	default:
		return -ENOENT;
	}
}

static int demux_c15_set(u64 id, void __user *uaddr)
{
	u32 val, newval;
	u32 __user *uval = uaddr;

	/* Fail if we have unknown bits set. */
	if (id & ~(KVM_REG_ARCH_MASK|KVM_REG_SIZE_MASK|KVM_REG_ARM_COPROC_MASK
		   | ((1 << KVM_REG_ARM_COPROC_SHIFT)-1)))
		return -ENOENT;

	switch (id & KVM_REG_ARM_DEMUX_ID_MASK) {
	case KVM_REG_ARM_DEMUX_ID_CCSIDR:
		if (KVM_REG_SIZE(id) != 4)
			return -ENOENT;
		val = (id & KVM_REG_ARM_DEMUX_VAL_MASK)
			>> KVM_REG_ARM_DEMUX_VAL_SHIFT;
		if (!is_valid_cache(val))
			return -ENOENT;

		if (get_user(newval, uval))
			return -EFAULT;

		/* This is also invariant: you can't change it. */
		if (newval != get_ccsidr(val))
			return -EINVAL;
		return 0;
	default:
		return -ENOENT;
	}
}

int kvm_arm_sys_reg_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
{
	const struct sys_reg_desc *r;
	void __user *uaddr = (void __user *)(unsigned long)reg->addr;

	if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_DEMUX)
		return demux_c15_get(reg->id, uaddr);

	if (KVM_REG_SIZE(reg->id) != sizeof(__u64))
		return -ENOENT;

	r = index_to_sys_reg_desc(vcpu, reg->id);
	if (!r)
		return get_invariant_sys_reg(reg->id, uaddr);

	return reg_to_user(uaddr, &vcpu_sys_reg(vcpu, r->reg), reg->id);
}

int kvm_arm_sys_reg_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
{
	const struct sys_reg_desc *r;
	void __user *uaddr = (void __user *)(unsigned long)reg->addr;

	if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_DEMUX)
		return demux_c15_set(reg->id, uaddr);

	if (KVM_REG_SIZE(reg->id) != sizeof(__u64))
		return -ENOENT;

	r = index_to_sys_reg_desc(vcpu, reg->id);
	if (!r)
		return set_invariant_sys_reg(reg->id, uaddr);

	return reg_from_user(&vcpu_sys_reg(vcpu, r->reg), uaddr, reg->id);
}

static unsigned int num_demux_regs(void)
{
	unsigned int i, count = 0;

	for (i = 0; i < CSSELR_MAX; i++)
		if (is_valid_cache(i))
			count++;

	return count;
}

static int write_demux_regids(u64 __user *uindices)
{
	u64 val = KVM_REG_ARM | KVM_REG_SIZE_U32 | KVM_REG_ARM_DEMUX;
	unsigned int i;

	val |= KVM_REG_ARM_DEMUX_ID_CCSIDR;
	for (i = 0; i < CSSELR_MAX; i++) {
		if (!is_valid_cache(i))
			continue;
		if (put_user(val | i, uindices))
			return -EFAULT;
		uindices++;
	}
	return 0;
}

static u64 sys_reg_to_index(const struct sys_reg_desc *reg)
{
	return (KVM_REG_ARM64 | KVM_REG_SIZE_U64 |
		KVM_REG_ARM64_SYSREG |
		(reg->Op0 << KVM_REG_ARM64_SYSREG_OP0_SHIFT) |
		(reg->Op1 << KVM_REG_ARM64_SYSREG_OP1_SHIFT) |
		(reg->CRn << KVM_REG_ARM64_SYSREG_CRN_SHIFT) |
		(reg->CRm << KVM_REG_ARM64_SYSREG_CRM_SHIFT) |
		(reg->Op2 << KVM_REG_ARM64_SYSREG_OP2_SHIFT));
}

static bool copy_reg_to_user(const struct sys_reg_desc *reg, u64 __user **uind)
{
	if (!*uind)
		return true;

	if (put_user(sys_reg_to_index(reg), *uind))
		return false;

	(*uind)++;
	return true;
}

/* Assumed ordered tables, see kvm_sys_reg_table_init. */
static int walk_sys_regs(struct kvm_vcpu *vcpu, u64 __user *uind)
{
	const struct sys_reg_desc *i1, *i2, *end1, *end2;
	unsigned int total = 0;
	size_t num;

	/* We check for duplicates here, to allow arch-specific overrides. */
	i1 = get_target_table(vcpu->arch.target, true, &num);
	end1 = i1 + num;
	i2 = sys_reg_descs;
	end2 = sys_reg_descs + ARRAY_SIZE(sys_reg_descs);

	BUG_ON(i1 == end1 || i2 == end2);

	/* Walk carefully, as both tables may refer to the same register. */
	while (i1 || i2) {
		int cmp = cmp_sys_reg(i1, i2);
		/* target-specific overrides generic entry. */
		if (cmp <= 0) {
			/* Ignore registers we trap but don't save. */
			if (i1->reg) {
				if (!copy_reg_to_user(i1, &uind))
					return -EFAULT;
				total++;
			}
		} else {
			/* Ignore registers we trap but don't save. */
			if (i2->reg) {
				if (!copy_reg_to_user(i2, &uind))
					return -EFAULT;
				total++;
			}
		}

		if (cmp <= 0 && ++i1 == end1)
			i1 = NULL;
		if (cmp >= 0 && ++i2 == end2)
			i2 = NULL;
	}
	return total;
}

unsigned long kvm_arm_num_sys_reg_descs(struct kvm_vcpu *vcpu)
{
	return ARRAY_SIZE(invariant_sys_regs)
		+ num_demux_regs()
		+ walk_sys_regs(vcpu, (u64 __user *)NULL);
}

int kvm_arm_copy_sys_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
{
	unsigned int i;
	int err;

	/* Then give them all the invariant registers' indices. */
	for (i = 0; i < ARRAY_SIZE(invariant_sys_regs); i++) {
		if (put_user(sys_reg_to_index(&invariant_sys_regs[i]), uindices))
			return -EFAULT;
		uindices++;
	}

	err = walk_sys_regs(vcpu, uindices);
	if (err < 0)
		return err;
	uindices += err;

	return write_demux_regids(uindices);
}

void kvm_sys_reg_table_init(void)
{
	unsigned int i;
	struct sys_reg_desc clidr;

	/* Make sure tables are unique and in order. */
	for (i = 1; i < ARRAY_SIZE(sys_reg_descs); i++)
		BUG_ON(cmp_sys_reg(&sys_reg_descs[i-1], &sys_reg_descs[i]) >= 0);

	/* We abuse the reset function to overwrite the table itself. */
	for (i = 0; i < ARRAY_SIZE(invariant_sys_regs); i++)
		invariant_sys_regs[i].reset(NULL, &invariant_sys_regs[i]);

	/*
	 * CLIDR format is awkward, so clean it up.  See ARM B4.1.20:
	 *
	 *   If software reads the Cache Type fields from Ctype1
	 *   upwards, once it has seen a value of 0b000, no caches
	 *   exist at further-out levels of the hierarchy. So, for
	 *   example, if Ctype3 is the first Cache Type field with a
	 *   value of 0b000, the values of Ctype4 to Ctype7 must be
	 *   ignored.
	 */
	get_clidr_el1(NULL, &clidr); /* Ugly... */
	cache_levels = clidr.val;
	for (i = 0; i < 7; i++)
		if (((cache_levels >> (i*3)) & 7) == 0)
			break;
	/* Clear all higher bits. */
	cache_levels &= (1 << (i*3))-1;
}

/**
 * kvm_reset_sys_regs - sets system registers to reset value
 * @vcpu: The VCPU pointer
 *
 * This function finds the right table above and sets the registers on the
 * virtual CPU struct to their architecturally defined reset values.
 */
void kvm_reset_sys_regs(struct kvm_vcpu *vcpu)
{
	size_t num;
	const struct sys_reg_desc *table;

	/* Catch someone adding a register without putting in reset entry. */
	memset(&vcpu->arch.ctxt.sys_regs, 0x42, sizeof(vcpu->arch.ctxt.sys_regs));

	/* Generic chip reset first (so target could override). */
	reset_sys_reg_descs(vcpu, sys_reg_descs, ARRAY_SIZE(sys_reg_descs));

	table = get_target_table(vcpu->arch.target, true, &num);
	reset_sys_reg_descs(vcpu, table, num);

	for (num = 1; num < NR_SYS_REGS; num++)
		if (vcpu_sys_reg(vcpu, num) == 0x4242424242424242)
			panic("Didn't reset vcpu_sys_reg(%zi)", num);
}