aboutsummaryrefslogtreecommitdiff
path: root/drivers/spi/spi-intel.c
blob: 66063687ae2714745f869ddb78c903b32fcf031b (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
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Intel PCH/PCU SPI flash driver.
 *
 * Copyright (C) 2016 - 2022, Intel Corporation
 * Author: Mika Westerberg <mika.westerberg@linux.intel.com>
 */

#include <linux/iopoll.h>
#include <linux/module.h>

#include <linux/mtd/partitions.h>
#include <linux/mtd/spi-nor.h>

#include <linux/spi/flash.h>
#include <linux/spi/spi.h>
#include <linux/spi/spi-mem.h>

#include "spi-intel.h"

/* Offsets are from @ispi->base */
#define BFPREG				0x00

#define HSFSTS_CTL			0x04
#define HSFSTS_CTL_FSMIE		BIT(31)
#define HSFSTS_CTL_FDBC_SHIFT		24
#define HSFSTS_CTL_FDBC_MASK		(0x3f << HSFSTS_CTL_FDBC_SHIFT)

#define HSFSTS_CTL_FCYCLE_SHIFT		17
#define HSFSTS_CTL_FCYCLE_MASK		(0x0f << HSFSTS_CTL_FCYCLE_SHIFT)
/* HW sequencer opcodes */
#define HSFSTS_CTL_FCYCLE_READ		(0x00 << HSFSTS_CTL_FCYCLE_SHIFT)
#define HSFSTS_CTL_FCYCLE_WRITE		(0x02 << HSFSTS_CTL_FCYCLE_SHIFT)
#define HSFSTS_CTL_FCYCLE_ERASE		(0x03 << HSFSTS_CTL_FCYCLE_SHIFT)
#define HSFSTS_CTL_FCYCLE_ERASE_64K	(0x04 << HSFSTS_CTL_FCYCLE_SHIFT)
#define HSFSTS_CTL_FCYCLE_RDID		(0x06 << HSFSTS_CTL_FCYCLE_SHIFT)
#define HSFSTS_CTL_FCYCLE_WRSR		(0x07 << HSFSTS_CTL_FCYCLE_SHIFT)
#define HSFSTS_CTL_FCYCLE_RDSR		(0x08 << HSFSTS_CTL_FCYCLE_SHIFT)

#define HSFSTS_CTL_FGO			BIT(16)
#define HSFSTS_CTL_FLOCKDN		BIT(15)
#define HSFSTS_CTL_FDV			BIT(14)
#define HSFSTS_CTL_SCIP			BIT(5)
#define HSFSTS_CTL_AEL			BIT(2)
#define HSFSTS_CTL_FCERR		BIT(1)
#define HSFSTS_CTL_FDONE		BIT(0)

#define FADDR				0x08
#define DLOCK				0x0c
#define FDATA(n)			(0x10 + ((n) * 4))

#define FRACC				0x50

#define FREG(n)				(0x54 + ((n) * 4))
#define FREG_BASE_MASK			0x3fff
#define FREG_LIMIT_SHIFT		16
#define FREG_LIMIT_MASK			(0x03fff << FREG_LIMIT_SHIFT)

/* Offset is from @ispi->pregs */
#define PR(n)				((n) * 4)
#define PR_WPE				BIT(31)
#define PR_LIMIT_SHIFT			16
#define PR_LIMIT_MASK			(0x3fff << PR_LIMIT_SHIFT)
#define PR_RPE				BIT(15)
#define PR_BASE_MASK			0x3fff

/* Offsets are from @ispi->sregs */
#define SSFSTS_CTL			0x00
#define SSFSTS_CTL_FSMIE		BIT(23)
#define SSFSTS_CTL_DS			BIT(22)
#define SSFSTS_CTL_DBC_SHIFT		16
#define SSFSTS_CTL_SPOP			BIT(11)
#define SSFSTS_CTL_ACS			BIT(10)
#define SSFSTS_CTL_SCGO			BIT(9)
#define SSFSTS_CTL_COP_SHIFT		12
#define SSFSTS_CTL_FRS			BIT(7)
#define SSFSTS_CTL_DOFRS		BIT(6)
#define SSFSTS_CTL_AEL			BIT(4)
#define SSFSTS_CTL_FCERR		BIT(3)
#define SSFSTS_CTL_FDONE		BIT(2)
#define SSFSTS_CTL_SCIP			BIT(0)

#define PREOP_OPTYPE			0x04
#define OPMENU0				0x08
#define OPMENU1				0x0c

#define OPTYPE_READ_NO_ADDR		0
#define OPTYPE_WRITE_NO_ADDR		1
#define OPTYPE_READ_WITH_ADDR		2
#define OPTYPE_WRITE_WITH_ADDR		3

/* CPU specifics */
#define BYT_PR				0x74
#define BYT_SSFSTS_CTL			0x90
#define BYT_FREG_NUM			5
#define BYT_PR_NUM			5

#define LPT_PR				0x74
#define LPT_SSFSTS_CTL			0x90
#define LPT_FREG_NUM			5
#define LPT_PR_NUM			5

#define BXT_PR				0x84
#define BXT_SSFSTS_CTL			0xa0
#define BXT_FREG_NUM			12
#define BXT_PR_NUM			6

#define CNL_PR				0x84
#define CNL_FREG_NUM			6
#define CNL_PR_NUM			5

#define LVSCC				0xc4
#define UVSCC				0xc8
#define ERASE_OPCODE_SHIFT		8
#define ERASE_OPCODE_MASK		(0xff << ERASE_OPCODE_SHIFT)
#define ERASE_64K_OPCODE_SHIFT		16
#define ERASE_64K_OPCODE_MASK		(0xff << ERASE_OPCODE_SHIFT)

#define INTEL_SPI_TIMEOUT		5000 /* ms */
#define INTEL_SPI_FIFO_SZ		64

/**
 * struct intel_spi - Driver private data
 * @dev: Device pointer
 * @info: Pointer to board specific info
 * @base: Beginning of MMIO space
 * @pregs: Start of protection registers
 * @sregs: Start of software sequencer registers
 * @master: Pointer to the SPI controller structure
 * @nregions: Maximum number of regions
 * @pr_num: Maximum number of protected range registers
 * @locked: Is SPI setting locked
 * @swseq_reg: Use SW sequencer in register reads/writes
 * @swseq_erase: Use SW sequencer in erase operation
 * @atomic_preopcode: Holds preopcode when atomic sequence is requested
 * @opcodes: Opcodes which are supported. This are programmed by BIOS
 *           before it locks down the controller.
 * @mem_ops: Pointer to SPI MEM ops supported by the controller
 */
struct intel_spi {
	struct device *dev;
	const struct intel_spi_boardinfo *info;
	void __iomem *base;
	void __iomem *pregs;
	void __iomem *sregs;
	struct spi_controller *master;
	size_t nregions;
	size_t pr_num;
	bool locked;
	bool swseq_reg;
	bool swseq_erase;
	u8 atomic_preopcode;
	u8 opcodes[8];
	const struct intel_spi_mem_op *mem_ops;
};

struct intel_spi_mem_op {
	struct spi_mem_op mem_op;
	u32 replacement_op;
	int (*exec_op)(struct intel_spi *ispi,
		       const struct intel_spi_mem_op *iop,
		       const struct spi_mem_op *op);
};

static bool writeable;
module_param(writeable, bool, 0);
MODULE_PARM_DESC(writeable, "Enable write access to SPI flash chip (default=0)");

static void intel_spi_dump_regs(struct intel_spi *ispi)
{
	u32 value;
	int i;

	dev_dbg(ispi->dev, "BFPREG=0x%08x\n", readl(ispi->base + BFPREG));

	value = readl(ispi->base + HSFSTS_CTL);
	dev_dbg(ispi->dev, "HSFSTS_CTL=0x%08x\n", value);
	if (value & HSFSTS_CTL_FLOCKDN)
		dev_dbg(ispi->dev, "-> Locked\n");

	dev_dbg(ispi->dev, "FADDR=0x%08x\n", readl(ispi->base + FADDR));
	dev_dbg(ispi->dev, "DLOCK=0x%08x\n", readl(ispi->base + DLOCK));

	for (i = 0; i < 16; i++)
		dev_dbg(ispi->dev, "FDATA(%d)=0x%08x\n",
			i, readl(ispi->base + FDATA(i)));

	dev_dbg(ispi->dev, "FRACC=0x%08x\n", readl(ispi->base + FRACC));

	for (i = 0; i < ispi->nregions; i++)
		dev_dbg(ispi->dev, "FREG(%d)=0x%08x\n", i,
			readl(ispi->base + FREG(i)));
	for (i = 0; i < ispi->pr_num; i++)
		dev_dbg(ispi->dev, "PR(%d)=0x%08x\n", i,
			readl(ispi->pregs + PR(i)));

	if (ispi->sregs) {
		value = readl(ispi->sregs + SSFSTS_CTL);
		dev_dbg(ispi->dev, "SSFSTS_CTL=0x%08x\n", value);
		dev_dbg(ispi->dev, "PREOP_OPTYPE=0x%08x\n",
			readl(ispi->sregs + PREOP_OPTYPE));
		dev_dbg(ispi->dev, "OPMENU0=0x%08x\n",
			readl(ispi->sregs + OPMENU0));
		dev_dbg(ispi->dev, "OPMENU1=0x%08x\n",
			readl(ispi->sregs + OPMENU1));
	}

	dev_dbg(ispi->dev, "LVSCC=0x%08x\n", readl(ispi->base + LVSCC));
	dev_dbg(ispi->dev, "UVSCC=0x%08x\n", readl(ispi->base + UVSCC));

	dev_dbg(ispi->dev, "Protected regions:\n");
	for (i = 0; i < ispi->pr_num; i++) {
		u32 base, limit;

		value = readl(ispi->pregs + PR(i));
		if (!(value & (PR_WPE | PR_RPE)))
			continue;

		limit = (value & PR_LIMIT_MASK) >> PR_LIMIT_SHIFT;
		base = value & PR_BASE_MASK;

		dev_dbg(ispi->dev, " %02d base: 0x%08x limit: 0x%08x [%c%c]\n",
			i, base << 12, (limit << 12) | 0xfff,
			value & PR_WPE ? 'W' : '.', value & PR_RPE ? 'R' : '.');
	}

	dev_dbg(ispi->dev, "Flash regions:\n");
	for (i = 0; i < ispi->nregions; i++) {
		u32 region, base, limit;

		region = readl(ispi->base + FREG(i));
		base = region & FREG_BASE_MASK;
		limit = (region & FREG_LIMIT_MASK) >> FREG_LIMIT_SHIFT;

		if (base >= limit || (i > 0 && limit == 0))
			dev_dbg(ispi->dev, " %02d disabled\n", i);
		else
			dev_dbg(ispi->dev, " %02d base: 0x%08x limit: 0x%08x\n",
				i, base << 12, (limit << 12) | 0xfff);
	}

	dev_dbg(ispi->dev, "Using %cW sequencer for register access\n",
		ispi->swseq_reg ? 'S' : 'H');
	dev_dbg(ispi->dev, "Using %cW sequencer for erase operation\n",
		ispi->swseq_erase ? 'S' : 'H');
}

/* Reads max INTEL_SPI_FIFO_SZ bytes from the device fifo */
static int intel_spi_read_block(struct intel_spi *ispi, void *buf, size_t size)
{
	size_t bytes;
	int i = 0;

	if (size > INTEL_SPI_FIFO_SZ)
		return -EINVAL;

	while (size > 0) {
		bytes = min_t(size_t, size, 4);
		memcpy_fromio(buf, ispi->base + FDATA(i), bytes);
		size -= bytes;
		buf += bytes;
		i++;
	}

	return 0;
}

/* Writes max INTEL_SPI_FIFO_SZ bytes to the device fifo */
static int intel_spi_write_block(struct intel_spi *ispi, const void *buf,
				 size_t size)
{
	size_t bytes;
	int i = 0;

	if (size > INTEL_SPI_FIFO_SZ)
		return -EINVAL;

	while (size > 0) {
		bytes = min_t(size_t, size, 4);
		memcpy_toio(ispi->base + FDATA(i), buf, bytes);
		size -= bytes;
		buf += bytes;
		i++;
	}

	return 0;
}

static int intel_spi_wait_hw_busy(struct intel_spi *ispi)
{
	u32 val;

	return readl_poll_timeout(ispi->base + HSFSTS_CTL, val,
				  !(val & HSFSTS_CTL_SCIP), 0,
				  INTEL_SPI_TIMEOUT * 1000);
}

static int intel_spi_wait_sw_busy(struct intel_spi *ispi)
{
	u32 val;

	return readl_poll_timeout(ispi->sregs + SSFSTS_CTL, val,
				  !(val & SSFSTS_CTL_SCIP), 0,
				  INTEL_SPI_TIMEOUT * 1000);
}

static bool intel_spi_set_writeable(struct intel_spi *ispi)
{
	if (!ispi->info->set_writeable)
		return false;

	return ispi->info->set_writeable(ispi->base, ispi->info->data);
}

static int intel_spi_opcode_index(struct intel_spi *ispi, u8 opcode, int optype)
{
	int i;
	int preop;

	if (ispi->locked) {
		for (i = 0; i < ARRAY_SIZE(ispi->opcodes); i++)
			if (ispi->opcodes[i] == opcode)
				return i;

		return -EINVAL;
	}

	/* The lock is off, so just use index 0 */
	writel(opcode, ispi->sregs + OPMENU0);
	preop = readw(ispi->sregs + PREOP_OPTYPE);
	writel(optype << 16 | preop, ispi->sregs + PREOP_OPTYPE);

	return 0;
}

static int intel_spi_hw_cycle(struct intel_spi *ispi, u8 opcode, size_t len)
{
	u32 val, status;
	int ret;

	val = readl(ispi->base + HSFSTS_CTL);
	val &= ~(HSFSTS_CTL_FCYCLE_MASK | HSFSTS_CTL_FDBC_MASK);

	switch (opcode) {
	case SPINOR_OP_RDID:
		val |= HSFSTS_CTL_FCYCLE_RDID;
		break;
	case SPINOR_OP_WRSR:
		val |= HSFSTS_CTL_FCYCLE_WRSR;
		break;
	case SPINOR_OP_RDSR:
		val |= HSFSTS_CTL_FCYCLE_RDSR;
		break;
	default:
		return -EINVAL;
	}

	if (len > INTEL_SPI_FIFO_SZ)
		return -EINVAL;

	val |= (len - 1) << HSFSTS_CTL_FDBC_SHIFT;
	val |= HSFSTS_CTL_FCERR | HSFSTS_CTL_FDONE;
	val |= HSFSTS_CTL_FGO;
	writel(val, ispi->base + HSFSTS_CTL);

	ret = intel_spi_wait_hw_busy(ispi);
	if (ret)
		return ret;

	status = readl(ispi->base + HSFSTS_CTL);
	if (status & HSFSTS_CTL_FCERR)
		return -EIO;
	else if (status & HSFSTS_CTL_AEL)
		return -EACCES;

	return 0;
}

static int intel_spi_sw_cycle(struct intel_spi *ispi, u8 opcode, size_t len,
			      int optype)
{
	u32 val = 0, status;
	u8 atomic_preopcode;
	int ret;

	ret = intel_spi_opcode_index(ispi, opcode, optype);
	if (ret < 0)
		return ret;

	if (len > INTEL_SPI_FIFO_SZ)
		return -EINVAL;

	/*
	 * Always clear it after each SW sequencer operation regardless
	 * of whether it is successful or not.
	 */
	atomic_preopcode = ispi->atomic_preopcode;
	ispi->atomic_preopcode = 0;

	/* Only mark 'Data Cycle' bit when there is data to be transferred */
	if (len > 0)
		val = ((len - 1) << SSFSTS_CTL_DBC_SHIFT) | SSFSTS_CTL_DS;
	val |= ret << SSFSTS_CTL_COP_SHIFT;
	val |= SSFSTS_CTL_FCERR | SSFSTS_CTL_FDONE;
	val |= SSFSTS_CTL_SCGO;
	if (atomic_preopcode) {
		u16 preop;

		switch (optype) {
		case OPTYPE_WRITE_NO_ADDR:
		case OPTYPE_WRITE_WITH_ADDR:
			/* Pick matching preopcode for the atomic sequence */
			preop = readw(ispi->sregs + PREOP_OPTYPE);
			if ((preop & 0xff) == atomic_preopcode)
				; /* Do nothing */
			else if ((preop >> 8) == atomic_preopcode)
				val |= SSFSTS_CTL_SPOP;
			else
				return -EINVAL;

			/* Enable atomic sequence */
			val |= SSFSTS_CTL_ACS;
			break;

		default:
			return -EINVAL;
		}
	}
	writel(val, ispi->sregs + SSFSTS_CTL);

	ret = intel_spi_wait_sw_busy(ispi);
	if (ret)
		return ret;

	status = readl(ispi->sregs + SSFSTS_CTL);
	if (status & SSFSTS_CTL_FCERR)
		return -EIO;
	else if (status & SSFSTS_CTL_AEL)
		return -EACCES;

	return 0;
}

static int intel_spi_read_reg(struct intel_spi *ispi,
			      const struct intel_spi_mem_op *iop,
			      const struct spi_mem_op *op)
{
	size_t nbytes = op->data.nbytes;
	u8 opcode = op->cmd.opcode;
	int ret;

	/* Address of the first chip */
	writel(0, ispi->base + FADDR);

	if (ispi->swseq_reg)
		ret = intel_spi_sw_cycle(ispi, opcode, nbytes,
					 OPTYPE_READ_NO_ADDR);
	else
		ret = intel_spi_hw_cycle(ispi, opcode, nbytes);

	if (ret)
		return ret;

	return intel_spi_read_block(ispi, op->data.buf.in, nbytes);
}

static int intel_spi_write_reg(struct intel_spi *ispi,
			       const struct intel_spi_mem_op *iop,
			       const struct spi_mem_op *op)
{
	size_t nbytes = op->data.nbytes;
	u8 opcode = op->cmd.opcode;
	int ret;

	/*
	 * This is handled with atomic operation and preop code in Intel
	 * controller so we only verify that it is available. If the
	 * controller is not locked, program the opcode to the PREOP
	 * register for later use.
	 *
	 * When hardware sequencer is used there is no need to program
	 * any opcodes (it handles them automatically as part of a command).
	 */
	if (opcode == SPINOR_OP_WREN) {
		u16 preop;

		if (!ispi->swseq_reg)
			return 0;

		preop = readw(ispi->sregs + PREOP_OPTYPE);
		if ((preop & 0xff) != opcode && (preop >> 8) != opcode) {
			if (ispi->locked)
				return -EINVAL;
			writel(opcode, ispi->sregs + PREOP_OPTYPE);
		}

		/*
		 * This enables atomic sequence on next SW sycle. Will
		 * be cleared after next operation.
		 */
		ispi->atomic_preopcode = opcode;
		return 0;
	}

	/*
	 * We hope that HW sequencer will do the right thing automatically and
	 * with the SW sequencer we cannot use preopcode anyway, so just ignore
	 * the Write Disable operation and pretend it was completed
	 * successfully.
	 */
	if (opcode == SPINOR_OP_WRDI)
		return 0;

	writel(0, ispi->base + FADDR);

	/* Write the value beforehand */
	ret = intel_spi_write_block(ispi, op->data.buf.out, nbytes);
	if (ret)
		return ret;

	if (ispi->swseq_reg)
		return intel_spi_sw_cycle(ispi, opcode, nbytes,
					  OPTYPE_WRITE_NO_ADDR);
	return intel_spi_hw_cycle(ispi, opcode, nbytes);
}

static int intel_spi_read(struct intel_spi *ispi,
			  const struct intel_spi_mem_op *iop,
			  const struct spi_mem_op *op)
{
	void *read_buf = op->data.buf.in;
	size_t block_size, nbytes = op->data.nbytes;
	u32 addr = op->addr.val;
	u32 val, status;
	int ret;

	/*
	 * Atomic sequence is not expected with HW sequencer reads. Make
	 * sure it is cleared regardless.
	 */
	if (WARN_ON_ONCE(ispi->atomic_preopcode))
		ispi->atomic_preopcode = 0;

	while (nbytes > 0) {
		block_size = min_t(size_t, nbytes, INTEL_SPI_FIFO_SZ);

		/* Read cannot cross 4K boundary */
		block_size = min_t(loff_t, addr + block_size,
				   round_up(addr + 1, SZ_4K)) - addr;

		writel(addr, ispi->base + FADDR);

		val = readl(ispi->base + HSFSTS_CTL);
		val &= ~(HSFSTS_CTL_FDBC_MASK | HSFSTS_CTL_FCYCLE_MASK);
		val |= HSFSTS_CTL_AEL | HSFSTS_CTL_FCERR | HSFSTS_CTL_FDONE;
		val |= (block_size - 1) << HSFSTS_CTL_FDBC_SHIFT;
		val |= HSFSTS_CTL_FCYCLE_READ;
		val |= HSFSTS_CTL_FGO;
		writel(val, ispi->base + HSFSTS_CTL);

		ret = intel_spi_wait_hw_busy(ispi);
		if (ret)
			return ret;

		status = readl(ispi->base + HSFSTS_CTL);
		if (status & HSFSTS_CTL_FCERR)
			ret = -EIO;
		else if (status & HSFSTS_CTL_AEL)
			ret = -EACCES;

		if (ret < 0) {
			dev_err(ispi->dev, "read error: %x: %#x\n", addr, status);
			return ret;
		}

		ret = intel_spi_read_block(ispi, read_buf, block_size);
		if (ret)
			return ret;

		nbytes -= block_size;
		addr += block_size;
		read_buf += block_size;
	}

	return 0;
}

static int intel_spi_write(struct intel_spi *ispi,
			   const struct intel_spi_mem_op *iop,
			   const struct spi_mem_op *op)
{
	size_t block_size, nbytes = op->data.nbytes;
	const void *write_buf = op->data.buf.out;
	u32 addr = op->addr.val;
	u32 val, status;
	int ret;

	/* Not needed with HW sequencer write, make sure it is cleared */
	ispi->atomic_preopcode = 0;

	while (nbytes > 0) {
		block_size = min_t(size_t, nbytes, INTEL_SPI_FIFO_SZ);

		/* Write cannot cross 4K boundary */
		block_size = min_t(loff_t, addr + block_size,
				   round_up(addr + 1, SZ_4K)) - addr;

		writel(addr, ispi->base + FADDR);

		val = readl(ispi->base + HSFSTS_CTL);
		val &= ~(HSFSTS_CTL_FDBC_MASK | HSFSTS_CTL_FCYCLE_MASK);
		val |= HSFSTS_CTL_AEL | HSFSTS_CTL_FCERR | HSFSTS_CTL_FDONE;
		val |= (block_size - 1) << HSFSTS_CTL_FDBC_SHIFT;
		val |= HSFSTS_CTL_FCYCLE_WRITE;

		ret = intel_spi_write_block(ispi, write_buf, block_size);
		if (ret) {
			dev_err(ispi->dev, "failed to write block\n");
			return ret;
		}

		/* Start the write now */
		val |= HSFSTS_CTL_FGO;
		writel(val, ispi->base + HSFSTS_CTL);

		ret = intel_spi_wait_hw_busy(ispi);
		if (ret) {
			dev_err(ispi->dev, "timeout\n");
			return ret;
		}

		status = readl(ispi->base + HSFSTS_CTL);
		if (status & HSFSTS_CTL_FCERR)
			ret = -EIO;
		else if (status & HSFSTS_CTL_AEL)
			ret = -EACCES;

		if (ret < 0) {
			dev_err(ispi->dev, "write error: %x: %#x\n", addr, status);
			return ret;
		}

		nbytes -= block_size;
		addr += block_size;
		write_buf += block_size;
	}

	return 0;
}

static int intel_spi_erase(struct intel_spi *ispi,
			   const struct intel_spi_mem_op *iop,
			   const struct spi_mem_op *op)
{
	u8 opcode = op->cmd.opcode;
	u32 addr = op->addr.val;
	u32 val, status;
	int ret;

	writel(addr, ispi->base + FADDR);

	if (ispi->swseq_erase)
		return intel_spi_sw_cycle(ispi, opcode, 0,
					  OPTYPE_WRITE_WITH_ADDR);

	/* Not needed with HW sequencer erase, make sure it is cleared */
	ispi->atomic_preopcode = 0;

	val = readl(ispi->base + HSFSTS_CTL);
	val &= ~(HSFSTS_CTL_FDBC_MASK | HSFSTS_CTL_FCYCLE_MASK);
	val |= HSFSTS_CTL_AEL | HSFSTS_CTL_FCERR | HSFSTS_CTL_FDONE;
	val |= HSFSTS_CTL_FGO;
	val |= iop->replacement_op;
	writel(val, ispi->base + HSFSTS_CTL);

	ret = intel_spi_wait_hw_busy(ispi);
	if (ret)
		return ret;

	status = readl(ispi->base + HSFSTS_CTL);
	if (status & HSFSTS_CTL_FCERR)
		return -EIO;
	if (status & HSFSTS_CTL_AEL)
		return -EACCES;

	return 0;
}

static bool intel_spi_cmp_mem_op(const struct intel_spi_mem_op *iop,
				 const struct spi_mem_op *op)
{
	if (iop->mem_op.cmd.nbytes != op->cmd.nbytes ||
	    iop->mem_op.cmd.buswidth != op->cmd.buswidth ||
	    iop->mem_op.cmd.dtr != op->cmd.dtr ||
	    iop->mem_op.cmd.opcode != op->cmd.opcode)
		return false;

	if (iop->mem_op.addr.nbytes != op->addr.nbytes ||
	    iop->mem_op.addr.dtr != op->addr.dtr)
		return false;

	if (iop->mem_op.data.dir != op->data.dir ||
	    iop->mem_op.data.dtr != op->data.dtr)
		return false;

	if (iop->mem_op.data.dir != SPI_MEM_NO_DATA) {
		if (iop->mem_op.data.buswidth != op->data.buswidth)
			return false;
	}

	return true;
}

static const struct intel_spi_mem_op *
intel_spi_match_mem_op(struct intel_spi *ispi, const struct spi_mem_op *op)
{
	const struct intel_spi_mem_op *iop;

	for (iop = ispi->mem_ops; iop->mem_op.cmd.opcode; iop++) {
		if (intel_spi_cmp_mem_op(iop, op))
			break;
	}

	return iop->mem_op.cmd.opcode ? iop : NULL;
}

static bool intel_spi_supports_mem_op(struct spi_mem *mem,
				      const struct spi_mem_op *op)
{
	struct intel_spi *ispi = spi_master_get_devdata(mem->spi->master);
	const struct intel_spi_mem_op *iop;

	iop = intel_spi_match_mem_op(ispi, op);
	if (!iop) {
		dev_dbg(ispi->dev, "%#x not supported\n", op->cmd.opcode);
		return false;
	}

	/*
	 * For software sequencer check that the opcode is actually
	 * present in the opmenu if it is locked.
	 */
	if (ispi->swseq_reg && ispi->locked) {
		int i;

		/* Check if it is in the locked opcodes list */
		for (i = 0; i < ARRAY_SIZE(ispi->opcodes); i++) {
			if (ispi->opcodes[i] == op->cmd.opcode)
				return true;
		}

		dev_dbg(ispi->dev, "%#x not supported\n", op->cmd.opcode);
		return false;
	}

	return true;
}

static int intel_spi_exec_mem_op(struct spi_mem *mem, const struct spi_mem_op *op)
{
	struct intel_spi *ispi = spi_master_get_devdata(mem->spi->master);
	const struct intel_spi_mem_op *iop;

	iop = intel_spi_match_mem_op(ispi, op);
	if (!iop)
		return -EOPNOTSUPP;

	return iop->exec_op(ispi, iop, op);
}

static const char *intel_spi_get_name(struct spi_mem *mem)
{
	const struct intel_spi *ispi = spi_master_get_devdata(mem->spi->master);

	/*
	 * Return name of the flash controller device to be compatible
	 * with the MTD version.
	 */
	return dev_name(ispi->dev);
}

static int intel_spi_dirmap_create(struct spi_mem_dirmap_desc *desc)
{
	struct intel_spi *ispi = spi_master_get_devdata(desc->mem->spi->master);
	const struct intel_spi_mem_op *iop;

	iop = intel_spi_match_mem_op(ispi, &desc->info.op_tmpl);
	if (!iop)
		return -EOPNOTSUPP;

	desc->priv = (void *)iop;
	return 0;
}

static ssize_t intel_spi_dirmap_read(struct spi_mem_dirmap_desc *desc, u64 offs,
				     size_t len, void *buf)
{
	struct intel_spi *ispi = spi_master_get_devdata(desc->mem->spi->master);
	const struct intel_spi_mem_op *iop = desc->priv;
	struct spi_mem_op op = desc->info.op_tmpl;
	int ret;

	/* Fill in the gaps */
	op.addr.val = offs;
	op.data.nbytes = len;
	op.data.buf.in = buf;

	ret = iop->exec_op(ispi, iop, &op);
	return ret ? ret : len;
}

static ssize_t intel_spi_dirmap_write(struct spi_mem_dirmap_desc *desc, u64 offs,
				      size_t len, const void *buf)
{
	struct intel_spi *ispi = spi_master_get_devdata(desc->mem->spi->master);
	const struct intel_spi_mem_op *iop = desc->priv;
	struct spi_mem_op op = desc->info.op_tmpl;
	int ret;

	op.addr.val = offs;
	op.data.nbytes = len;
	op.data.buf.out = buf;

	ret = iop->exec_op(ispi, iop, &op);
	return ret ? ret : len;
}

static const struct spi_controller_mem_ops intel_spi_mem_ops = {
	.supports_op = intel_spi_supports_mem_op,
	.exec_op = intel_spi_exec_mem_op,
	.get_name = intel_spi_get_name,
	.dirmap_create = intel_spi_dirmap_create,
	.dirmap_read = intel_spi_dirmap_read,
	.dirmap_write = intel_spi_dirmap_write,
};

#define INTEL_SPI_OP_ADDR(__nbytes)					\
	{								\
		.nbytes = __nbytes,					\
	}

#define INTEL_SPI_OP_NO_DATA						\
	{								\
		.dir = SPI_MEM_NO_DATA,					\
	}

#define INTEL_SPI_OP_DATA_IN(__buswidth)				\
	{								\
		.dir = SPI_MEM_DATA_IN,					\
		.buswidth = __buswidth,					\
	}

#define INTEL_SPI_OP_DATA_OUT(__buswidth)				\
	{								\
		.dir = SPI_MEM_DATA_OUT,				\
		.buswidth = __buswidth,					\
	}

#define INTEL_SPI_MEM_OP(__cmd, __addr, __data, __exec_op)		\
	{								\
		.mem_op = {						\
			.cmd = __cmd,					\
			.addr = __addr,					\
			.data = __data,					\
		},							\
		.exec_op = __exec_op,					\
	}

#define INTEL_SPI_MEM_OP_REPL(__cmd, __addr, __data, __exec_op, __repl)	\
	{								\
		.mem_op = {						\
			.cmd = __cmd,					\
			.addr = __addr,					\
			.data = __data,					\
		},							\
		.exec_op = __exec_op,					\
		.replacement_op = __repl,				\
	}

/*
 * The controller handles pretty much everything internally based on the
 * SFDP data but we want to make sure we only support the operations
 * actually possible. Only check buswidth and transfer direction, the
 * core validates data.
 */
#define INTEL_SPI_GENERIC_OPS						\
	/* Status register operations */				\
	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_RDID, 1),		\
			 SPI_MEM_OP_NO_ADDR,				\
			 INTEL_SPI_OP_DATA_IN(1),			\
			 intel_spi_read_reg),				\
	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_RDSR, 1),		\
			 SPI_MEM_OP_NO_ADDR,				\
			 INTEL_SPI_OP_DATA_IN(1),			\
			 intel_spi_read_reg),				\
	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_WRSR, 1),		\
			 SPI_MEM_OP_NO_ADDR,				\
			 INTEL_SPI_OP_DATA_OUT(1),			\
			 intel_spi_write_reg),				\
	/* Normal read */						\
	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_READ, 1),		\
			 INTEL_SPI_OP_ADDR(3),				\
			 INTEL_SPI_OP_DATA_IN(1),			\
			 intel_spi_read),				\
	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_READ, 1),		\
			 INTEL_SPI_OP_ADDR(3),				\
			 INTEL_SPI_OP_DATA_IN(2),			\
			 intel_spi_read),				\
	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_READ, 1),		\
			 INTEL_SPI_OP_ADDR(3),				\
			 INTEL_SPI_OP_DATA_IN(4),			\
			 intel_spi_read),				\
	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_READ, 1),		\
			 INTEL_SPI_OP_ADDR(4),				\
			 INTEL_SPI_OP_DATA_IN(1),			\
			 intel_spi_read),				\
	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_READ, 1),		\
			 INTEL_SPI_OP_ADDR(4),				\
			 INTEL_SPI_OP_DATA_IN(2),			\
			 intel_spi_read),				\
	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_READ, 1),		\
			 INTEL_SPI_OP_ADDR(4),				\
			 INTEL_SPI_OP_DATA_IN(4),			\
			 intel_spi_read),				\
	/* Fast read */							\
	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_READ_FAST, 1),	\
			 INTEL_SPI_OP_ADDR(3),				\
			 INTEL_SPI_OP_DATA_IN(1),			\
			 intel_spi_read),				\
	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_READ_FAST, 1),	\
			 INTEL_SPI_OP_ADDR(3),				\
			 INTEL_SPI_OP_DATA_IN(2),			\
			 intel_spi_read),				\
	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_READ_FAST, 1),	\
			 INTEL_SPI_OP_ADDR(3),				\
			 INTEL_SPI_OP_DATA_IN(4),			\
			 intel_spi_read),				\
	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_READ_FAST, 1),	\
			 INTEL_SPI_OP_ADDR(4),				\
			 INTEL_SPI_OP_DATA_IN(1),			\
			 intel_spi_read),				\
	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_READ_FAST, 1),	\
			 INTEL_SPI_OP_ADDR(4),				\
			 INTEL_SPI_OP_DATA_IN(2),			\
			 intel_spi_read),				\
	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_READ_FAST, 1),	\
			 INTEL_SPI_OP_ADDR(4),				\
			 INTEL_SPI_OP_DATA_IN(4),			\
			 intel_spi_read),				\
	/* Read with 4-byte address opcode */				\
	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_READ_4B, 1),		\
			 INTEL_SPI_OP_ADDR(4),				\
			 INTEL_SPI_OP_DATA_IN(1),			\
			 intel_spi_read),				\
	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_READ_4B, 1),		\
			 INTEL_SPI_OP_ADDR(4),				\
			 INTEL_SPI_OP_DATA_IN(2),			\
			 intel_spi_read),				\
	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_READ_4B, 1),		\
			 INTEL_SPI_OP_ADDR(4),				\
			 INTEL_SPI_OP_DATA_IN(4),			\
			 intel_spi_read),				\
	/* Fast read with 4-byte address opcode */			\
	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_READ_FAST_4B, 1),	\
			 INTEL_SPI_OP_ADDR(4),				\
			 INTEL_SPI_OP_DATA_IN(1),			\
			 intel_spi_read),				\
	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_READ_FAST_4B, 1),	\
			 INTEL_SPI_OP_ADDR(4),				\
			 INTEL_SPI_OP_DATA_IN(2),			\
			 intel_spi_read),				\
	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_READ_FAST_4B, 1),	\
			 INTEL_SPI_OP_ADDR(4),				\
			 INTEL_SPI_OP_DATA_IN(4),			\
			 intel_spi_read),				\
	/* Write operations */						\
	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_PP, 1),		\
			 INTEL_SPI_OP_ADDR(3),				\
			 INTEL_SPI_OP_DATA_OUT(1),			\
			 intel_spi_write),				\
	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_PP, 1),		\
			 INTEL_SPI_OP_ADDR(4),				\
			 INTEL_SPI_OP_DATA_OUT(1),			\
			 intel_spi_write),				\
	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_PP_4B, 1),		\
			 INTEL_SPI_OP_ADDR(4),				\
			 INTEL_SPI_OP_DATA_OUT(1),			\
			 intel_spi_write),				\
	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_WREN, 1),		\
			 SPI_MEM_OP_NO_ADDR,				\
			 SPI_MEM_OP_NO_DATA,				\
			 intel_spi_write_reg),				\
	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_WRDI, 1),		\
			 SPI_MEM_OP_NO_ADDR,				\
			 SPI_MEM_OP_NO_DATA,				\
			 intel_spi_write_reg),				\
	/* Erase operations */						\
	INTEL_SPI_MEM_OP_REPL(SPI_MEM_OP_CMD(SPINOR_OP_BE_4K, 1),	\
			      INTEL_SPI_OP_ADDR(3),			\
			      SPI_MEM_OP_NO_DATA,			\
			      intel_spi_erase,				\
			      HSFSTS_CTL_FCYCLE_ERASE),			\
	INTEL_SPI_MEM_OP_REPL(SPI_MEM_OP_CMD(SPINOR_OP_BE_4K, 1),	\
			      INTEL_SPI_OP_ADDR(4),			\
			      SPI_MEM_OP_NO_DATA,			\
			      intel_spi_erase,				\
			      HSFSTS_CTL_FCYCLE_ERASE),			\
	INTEL_SPI_MEM_OP_REPL(SPI_MEM_OP_CMD(SPINOR_OP_BE_4K_4B, 1),	\
			      INTEL_SPI_OP_ADDR(4),			\
			      SPI_MEM_OP_NO_DATA,			\
			      intel_spi_erase,				\
			      HSFSTS_CTL_FCYCLE_ERASE)			\

static const struct intel_spi_mem_op generic_mem_ops[] = {
	INTEL_SPI_GENERIC_OPS,
	{ },
};

static const struct intel_spi_mem_op erase_64k_mem_ops[] = {
	INTEL_SPI_GENERIC_OPS,
	/* 64k sector erase operations */
	INTEL_SPI_MEM_OP_REPL(SPI_MEM_OP_CMD(SPINOR_OP_SE, 1),
			      INTEL_SPI_OP_ADDR(3),
			      SPI_MEM_OP_NO_DATA,
			      intel_spi_erase,
			      HSFSTS_CTL_FCYCLE_ERASE_64K),
	INTEL_SPI_MEM_OP_REPL(SPI_MEM_OP_CMD(SPINOR_OP_SE, 1),
			      INTEL_SPI_OP_ADDR(4),
			      SPI_MEM_OP_NO_DATA,
			      intel_spi_erase,
			      HSFSTS_CTL_FCYCLE_ERASE_64K),
	INTEL_SPI_MEM_OP_REPL(SPI_MEM_OP_CMD(SPINOR_OP_SE_4B, 1),
			      INTEL_SPI_OP_ADDR(4),
			      SPI_MEM_OP_NO_DATA,
			      intel_spi_erase,
			      HSFSTS_CTL_FCYCLE_ERASE_64K),
	{ },
};

static int intel_spi_init(struct intel_spi *ispi)
{
	u32 opmenu0, opmenu1, lvscc, uvscc, val;
	bool erase_64k = false;
	int i;

	switch (ispi->info->type) {
	case INTEL_SPI_BYT:
		ispi->sregs = ispi->base + BYT_SSFSTS_CTL;
		ispi->pregs = ispi->base + BYT_PR;
		ispi->nregions = BYT_FREG_NUM;
		ispi->pr_num = BYT_PR_NUM;
		ispi->swseq_reg = true;
		break;

	case INTEL_SPI_LPT:
		ispi->sregs = ispi->base + LPT_SSFSTS_CTL;
		ispi->pregs = ispi->base + LPT_PR;
		ispi->nregions = LPT_FREG_NUM;
		ispi->pr_num = LPT_PR_NUM;
		ispi->swseq_reg = true;
		break;

	case INTEL_SPI_BXT:
		ispi->sregs = ispi->base + BXT_SSFSTS_CTL;
		ispi->pregs = ispi->base + BXT_PR;
		ispi->nregions = BXT_FREG_NUM;
		ispi->pr_num = BXT_PR_NUM;
		erase_64k = true;
		break;

	case INTEL_SPI_CNL:
		ispi->sregs = NULL;
		ispi->pregs = ispi->base + CNL_PR;
		ispi->nregions = CNL_FREG_NUM;
		ispi->pr_num = CNL_PR_NUM;
		break;

	default:
		return -EINVAL;
	}

	/* Try to disable write protection if user asked to do so */
	if (writeable && !intel_spi_set_writeable(ispi)) {
		dev_warn(ispi->dev, "can't disable chip write protection\n");
		writeable = false;
	}

	/* Disable #SMI generation from HW sequencer */
	val = readl(ispi->base + HSFSTS_CTL);
	val &= ~HSFSTS_CTL_FSMIE;
	writel(val, ispi->base + HSFSTS_CTL);

	/*
	 * Determine whether erase operation should use HW or SW sequencer.
	 *
	 * The HW sequencer has a predefined list of opcodes, with only the
	 * erase opcode being programmable in LVSCC and UVSCC registers.
	 * If these registers don't contain a valid erase opcode, erase
	 * cannot be done using HW sequencer.
	 */
	lvscc = readl(ispi->base + LVSCC);
	uvscc = readl(ispi->base + UVSCC);
	if (!(lvscc & ERASE_OPCODE_MASK) || !(uvscc & ERASE_OPCODE_MASK))
		ispi->swseq_erase = true;
	/* SPI controller on Intel BXT supports 64K erase opcode */
	if (ispi->info->type == INTEL_SPI_BXT && !ispi->swseq_erase)
		if (!(lvscc & ERASE_64K_OPCODE_MASK) ||
		    !(uvscc & ERASE_64K_OPCODE_MASK))
			erase_64k = false;

	if (!ispi->sregs && (ispi->swseq_reg || ispi->swseq_erase)) {
		dev_err(ispi->dev, "software sequencer not supported, but required\n");
		return -EINVAL;
	}

	/*
	 * Some controllers can only do basic operations using hardware
	 * sequencer. All other operations are supposed to be carried out
	 * using software sequencer.
	 */
	if (ispi->swseq_reg) {
		/* Disable #SMI generation from SW sequencer */
		val = readl(ispi->sregs + SSFSTS_CTL);
		val &= ~SSFSTS_CTL_FSMIE;
		writel(val, ispi->sregs + SSFSTS_CTL);
	}

	/* Check controller's lock status */
	val = readl(ispi->base + HSFSTS_CTL);
	ispi->locked = !!(val & HSFSTS_CTL_FLOCKDN);

	if (ispi->locked && ispi->sregs) {
		/*
		 * BIOS programs allowed opcodes and then locks down the
		 * register. So read back what opcodes it decided to support.
		 * That's the set we are going to support as well.
		 */
		opmenu0 = readl(ispi->sregs + OPMENU0);
		opmenu1 = readl(ispi->sregs + OPMENU1);

		if (opmenu0 && opmenu1) {
			for (i = 0; i < ARRAY_SIZE(ispi->opcodes) / 2; i++) {
				ispi->opcodes[i] = opmenu0 >> i * 8;
				ispi->opcodes[i + 4] = opmenu1 >> i * 8;
			}
		}
	}

	if (erase_64k) {
		dev_dbg(ispi->dev, "Using erase_64k memory operations");
		ispi->mem_ops = erase_64k_mem_ops;
	} else {
		dev_dbg(ispi->dev, "Using generic memory operations");
		ispi->mem_ops = generic_mem_ops;
	}

	intel_spi_dump_regs(ispi);
	return 0;
}

static bool intel_spi_is_protected(const struct intel_spi *ispi,
				   unsigned int base, unsigned int limit)
{
	int i;

	for (i = 0; i < ispi->pr_num; i++) {
		u32 pr_base, pr_limit, pr_value;

		pr_value = readl(ispi->pregs + PR(i));
		if (!(pr_value & (PR_WPE | PR_RPE)))
			continue;

		pr_limit = (pr_value & PR_LIMIT_MASK) >> PR_LIMIT_SHIFT;
		pr_base = pr_value & PR_BASE_MASK;

		if (pr_base >= base && pr_limit <= limit)
			return true;
	}

	return false;
}

/*
 * There will be a single partition holding all enabled flash regions. We
 * call this "BIOS".
 */
static void intel_spi_fill_partition(struct intel_spi *ispi,
				     struct mtd_partition *part)
{
	u64 end;
	int i;

	memset(part, 0, sizeof(*part));

	/* Start from the mandatory descriptor region */
	part->size = 4096;
	part->name = "BIOS";

	/*
	 * Now try to find where this partition ends based on the flash
	 * region registers.
	 */
	for (i = 1; i < ispi->nregions; i++) {
		u32 region, base, limit;

		region = readl(ispi->base + FREG(i));
		base = region & FREG_BASE_MASK;
		limit = (region & FREG_LIMIT_MASK) >> FREG_LIMIT_SHIFT;

		if (base >= limit || limit == 0)
			continue;

		/*
		 * If any of the regions have protection bits set, make the
		 * whole partition read-only to be on the safe side.
		 *
		 * Also if the user did not ask the chip to be writeable
		 * mask the bit too.
		 */
		if (!writeable || intel_spi_is_protected(ispi, base, limit))
			part->mask_flags |= MTD_WRITEABLE;

		end = (limit << 12) + 4096;
		if (end > part->size)
			part->size = end;
	}
}

static int intel_spi_populate_chip(struct intel_spi *ispi)
{
	struct flash_platform_data *pdata;
	struct spi_board_info chip;

	pdata = devm_kzalloc(ispi->dev, sizeof(*pdata), GFP_KERNEL);
	if (!pdata)
		return -ENOMEM;

	pdata->nr_parts = 1;
	pdata->parts = devm_kcalloc(ispi->dev, pdata->nr_parts,
				    sizeof(*pdata->parts), GFP_KERNEL);
	if (!pdata->parts)
		return -ENOMEM;

	intel_spi_fill_partition(ispi, pdata->parts);

	memset(&chip, 0, sizeof(chip));
	snprintf(chip.modalias, 8, "spi-nor");
	chip.platform_data = pdata;

	return spi_new_device(ispi->master, &chip) ? 0 : -ENODEV;
}

/**
 * intel_spi_probe() - Probe the Intel SPI flash controller
 * @dev: Pointer to the parent device
 * @mem: MMIO resource
 * @info: Platform specific information
 *
 * Probes Intel SPI flash controller and creates the flash chip device.
 * Returns %0 on success and negative errno in case of failure.
 */
int intel_spi_probe(struct device *dev, struct resource *mem,
		    const struct intel_spi_boardinfo *info)
{
	struct spi_controller *master;
	struct intel_spi *ispi;
	int ret;

	master = devm_spi_alloc_master(dev, sizeof(*ispi));
	if (!master)
		return -ENOMEM;

	master->mem_ops = &intel_spi_mem_ops;

	ispi = spi_master_get_devdata(master);

	ispi->base = devm_ioremap_resource(dev, mem);
	if (IS_ERR(ispi->base))
		return PTR_ERR(ispi->base);

	ispi->dev = dev;
	ispi->master = master;
	ispi->info = info;

	ret = intel_spi_init(ispi);
	if (ret)
		return ret;

	ret = devm_spi_register_master(dev, master);
	if (ret)
		return ret;

	return intel_spi_populate_chip(ispi);
}
EXPORT_SYMBOL_GPL(intel_spi_probe);

MODULE_DESCRIPTION("Intel PCH/PCU SPI flash core driver");
MODULE_AUTHOR("Mika Westerberg <mika.westerberg@linux.intel.com>");
MODULE_LICENSE("GPL v2");