aboutsummaryrefslogtreecommitdiff
path: root/drivers/mtd/spi-nor/sfdp.c
blob: 2257f1b4c2e2da6b72186b179ff18548a8514ac3 (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
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (C) 2005, Intec Automation Inc.
 * Copyright (C) 2014, Freescale Semiconductor, Inc.
 */

#include <linux/bitfield.h>
#include <linux/slab.h>
#include <linux/sort.h>
#include <linux/mtd/spi-nor.h>

#include "core.h"

#define SFDP_PARAM_HEADER_ID(p)	(((p)->id_msb << 8) | (p)->id_lsb)
#define SFDP_PARAM_HEADER_PTP(p) \
	(((p)->parameter_table_pointer[2] << 16) | \
	 ((p)->parameter_table_pointer[1] <<  8) | \
	 ((p)->parameter_table_pointer[0] <<  0))
#define SFDP_PARAM_HEADER_PARAM_LEN(p) ((p)->length * 4)

#define SFDP_BFPT_ID		0xff00	/* Basic Flash Parameter Table */
#define SFDP_SECTOR_MAP_ID	0xff81	/* Sector Map Table */
#define SFDP_4BAIT_ID		0xff84  /* 4-byte Address Instruction Table */
#define SFDP_PROFILE1_ID	0xff05	/* xSPI Profile 1.0 table. */
#define SFDP_SCCR_MAP_ID	0xff87	/*
					 * Status, Control and Configuration
					 * Register Map.
					 */

#define SFDP_SIGNATURE		0x50444653U

struct sfdp_header {
	u32		signature; /* Ox50444653U <=> "SFDP" */
	u8		minor;
	u8		major;
	u8		nph; /* 0-base number of parameter headers */
	u8		unused;

	/* Basic Flash Parameter Table. */
	struct sfdp_parameter_header	bfpt_header;
};

/* Fast Read settings. */
struct sfdp_bfpt_read {
	/* The Fast Read x-y-z hardware capability in params->hwcaps.mask. */
	u32			hwcaps;

	/*
	 * The <supported_bit> bit in <supported_dword> BFPT DWORD tells us
	 * whether the Fast Read x-y-z command is supported.
	 */
	u32			supported_dword;
	u32			supported_bit;

	/*
	 * The half-word at offset <setting_shift> in <setting_dword> BFPT DWORD
	 * encodes the op code, the number of mode clocks and the number of wait
	 * states to be used by Fast Read x-y-z command.
	 */
	u32			settings_dword;
	u32			settings_shift;

	/* The SPI protocol for this Fast Read x-y-z command. */
	enum spi_nor_protocol	proto;
};

struct sfdp_bfpt_erase {
	/*
	 * The half-word at offset <shift> in DWORD <dword> encodes the
	 * op code and erase sector size to be used by Sector Erase commands.
	 */
	u32			dword;
	u32			shift;
};

#define SMPT_CMD_ADDRESS_LEN_MASK		GENMASK(23, 22)
#define SMPT_CMD_ADDRESS_LEN_0			(0x0UL << 22)
#define SMPT_CMD_ADDRESS_LEN_3			(0x1UL << 22)
#define SMPT_CMD_ADDRESS_LEN_4			(0x2UL << 22)
#define SMPT_CMD_ADDRESS_LEN_USE_CURRENT	(0x3UL << 22)

#define SMPT_CMD_READ_DUMMY_MASK		GENMASK(19, 16)
#define SMPT_CMD_READ_DUMMY_SHIFT		16
#define SMPT_CMD_READ_DUMMY(_cmd) \
	(((_cmd) & SMPT_CMD_READ_DUMMY_MASK) >> SMPT_CMD_READ_DUMMY_SHIFT)
#define SMPT_CMD_READ_DUMMY_IS_VARIABLE		0xfUL

#define SMPT_CMD_READ_DATA_MASK			GENMASK(31, 24)
#define SMPT_CMD_READ_DATA_SHIFT		24
#define SMPT_CMD_READ_DATA(_cmd) \
	(((_cmd) & SMPT_CMD_READ_DATA_MASK) >> SMPT_CMD_READ_DATA_SHIFT)

#define SMPT_CMD_OPCODE_MASK			GENMASK(15, 8)
#define SMPT_CMD_OPCODE_SHIFT			8
#define SMPT_CMD_OPCODE(_cmd) \
	(((_cmd) & SMPT_CMD_OPCODE_MASK) >> SMPT_CMD_OPCODE_SHIFT)

#define SMPT_MAP_REGION_COUNT_MASK		GENMASK(23, 16)
#define SMPT_MAP_REGION_COUNT_SHIFT		16
#define SMPT_MAP_REGION_COUNT(_header) \
	((((_header) & SMPT_MAP_REGION_COUNT_MASK) >> \
	  SMPT_MAP_REGION_COUNT_SHIFT) + 1)

#define SMPT_MAP_ID_MASK			GENMASK(15, 8)
#define SMPT_MAP_ID_SHIFT			8
#define SMPT_MAP_ID(_header) \
	(((_header) & SMPT_MAP_ID_MASK) >> SMPT_MAP_ID_SHIFT)

#define SMPT_MAP_REGION_SIZE_MASK		GENMASK(31, 8)
#define SMPT_MAP_REGION_SIZE_SHIFT		8
#define SMPT_MAP_REGION_SIZE(_region) \
	(((((_region) & SMPT_MAP_REGION_SIZE_MASK) >> \
	   SMPT_MAP_REGION_SIZE_SHIFT) + 1) * 256)

#define SMPT_MAP_REGION_ERASE_TYPE_MASK		GENMASK(3, 0)
#define SMPT_MAP_REGION_ERASE_TYPE(_region) \
	((_region) & SMPT_MAP_REGION_ERASE_TYPE_MASK)

#define SMPT_DESC_TYPE_MAP			BIT(1)
#define SMPT_DESC_END				BIT(0)

#define SFDP_4BAIT_DWORD_MAX	2

struct sfdp_4bait {
	/* The hardware capability. */
	u32		hwcaps;

	/*
	 * The <supported_bit> bit in DWORD1 of the 4BAIT tells us whether
	 * the associated 4-byte address op code is supported.
	 */
	u32		supported_bit;
};

/**
 * spi_nor_read_raw() - raw read of serial flash memory. read_opcode,
 *			addr_nbytes and read_dummy members of the struct spi_nor
 *			should be previously
 * set.
 * @nor:	pointer to a 'struct spi_nor'
 * @addr:	offset in the serial flash memory
 * @len:	number of bytes to read
 * @buf:	buffer where the data is copied into (dma-safe memory)
 *
 * Return: 0 on success, -errno otherwise.
 */
static int spi_nor_read_raw(struct spi_nor *nor, u32 addr, size_t len, u8 *buf)
{
	ssize_t ret;

	while (len) {
		ret = spi_nor_read_data(nor, addr, len, buf);
		if (ret < 0)
			return ret;
		if (!ret || ret > len)
			return -EIO;

		buf += ret;
		addr += ret;
		len -= ret;
	}
	return 0;
}

/**
 * spi_nor_read_sfdp() - read Serial Flash Discoverable Parameters.
 * @nor:	pointer to a 'struct spi_nor'
 * @addr:	offset in the SFDP area to start reading data from
 * @len:	number of bytes to read
 * @buf:	buffer where the SFDP data are copied into (dma-safe memory)
 *
 * Whatever the actual numbers of bytes for address and dummy cycles are
 * for (Fast) Read commands, the Read SFDP (5Ah) instruction is always
 * followed by a 3-byte address and 8 dummy clock cycles.
 *
 * Return: 0 on success, -errno otherwise.
 */
static int spi_nor_read_sfdp(struct spi_nor *nor, u32 addr,
			     size_t len, void *buf)
{
	u8 addr_nbytes, read_opcode, read_dummy;
	int ret;

	read_opcode = nor->read_opcode;
	addr_nbytes = nor->addr_nbytes;
	read_dummy = nor->read_dummy;

	nor->read_opcode = SPINOR_OP_RDSFDP;
	nor->addr_nbytes = 3;
	nor->read_dummy = 8;

	ret = spi_nor_read_raw(nor, addr, len, buf);

	nor->read_opcode = read_opcode;
	nor->addr_nbytes = addr_nbytes;
	nor->read_dummy = read_dummy;

	return ret;
}

/**
 * spi_nor_read_sfdp_dma_unsafe() - read Serial Flash Discoverable Parameters.
 * @nor:	pointer to a 'struct spi_nor'
 * @addr:	offset in the SFDP area to start reading data from
 * @len:	number of bytes to read
 * @buf:	buffer where the SFDP data are copied into
 *
 * Wrap spi_nor_read_sfdp() using a kmalloc'ed bounce buffer as @buf is now not
 * guaranteed to be dma-safe.
 *
 * Return: -ENOMEM if kmalloc() fails, the return code of spi_nor_read_sfdp()
 *          otherwise.
 */
static int spi_nor_read_sfdp_dma_unsafe(struct spi_nor *nor, u32 addr,
					size_t len, void *buf)
{
	void *dma_safe_buf;
	int ret;

	dma_safe_buf = kmalloc(len, GFP_KERNEL);
	if (!dma_safe_buf)
		return -ENOMEM;

	ret = spi_nor_read_sfdp(nor, addr, len, dma_safe_buf);
	memcpy(buf, dma_safe_buf, len);
	kfree(dma_safe_buf);

	return ret;
}

static void
spi_nor_set_read_settings_from_bfpt(struct spi_nor_read_command *read,
				    u16 half,
				    enum spi_nor_protocol proto)
{
	read->num_mode_clocks = (half >> 5) & 0x07;
	read->num_wait_states = (half >> 0) & 0x1f;
	read->opcode = (half >> 8) & 0xff;
	read->proto = proto;
}

static const struct sfdp_bfpt_read sfdp_bfpt_reads[] = {
	/* Fast Read 1-1-2 */
	{
		SNOR_HWCAPS_READ_1_1_2,
		BFPT_DWORD(1), BIT(16),	/* Supported bit */
		BFPT_DWORD(4), 0,	/* Settings */
		SNOR_PROTO_1_1_2,
	},

	/* Fast Read 1-2-2 */
	{
		SNOR_HWCAPS_READ_1_2_2,
		BFPT_DWORD(1), BIT(20),	/* Supported bit */
		BFPT_DWORD(4), 16,	/* Settings */
		SNOR_PROTO_1_2_2,
	},

	/* Fast Read 2-2-2 */
	{
		SNOR_HWCAPS_READ_2_2_2,
		BFPT_DWORD(5),  BIT(0),	/* Supported bit */
		BFPT_DWORD(6), 16,	/* Settings */
		SNOR_PROTO_2_2_2,
	},

	/* Fast Read 1-1-4 */
	{
		SNOR_HWCAPS_READ_1_1_4,
		BFPT_DWORD(1), BIT(22),	/* Supported bit */
		BFPT_DWORD(3), 16,	/* Settings */
		SNOR_PROTO_1_1_4,
	},

	/* Fast Read 1-4-4 */
	{
		SNOR_HWCAPS_READ_1_4_4,
		BFPT_DWORD(1), BIT(21),	/* Supported bit */
		BFPT_DWORD(3), 0,	/* Settings */
		SNOR_PROTO_1_4_4,
	},

	/* Fast Read 4-4-4 */
	{
		SNOR_HWCAPS_READ_4_4_4,
		BFPT_DWORD(5), BIT(4),	/* Supported bit */
		BFPT_DWORD(7), 16,	/* Settings */
		SNOR_PROTO_4_4_4,
	},
};

static const struct sfdp_bfpt_erase sfdp_bfpt_erases[] = {
	/* Erase Type 1 in DWORD8 bits[15:0] */
	{BFPT_DWORD(8), 0},

	/* Erase Type 2 in DWORD8 bits[31:16] */
	{BFPT_DWORD(8), 16},

	/* Erase Type 3 in DWORD9 bits[15:0] */
	{BFPT_DWORD(9), 0},

	/* Erase Type 4 in DWORD9 bits[31:16] */
	{BFPT_DWORD(9), 16},
};

/**
 * spi_nor_set_erase_settings_from_bfpt() - set erase type settings from BFPT
 * @erase:	pointer to a structure that describes a SPI NOR erase type
 * @size:	the size of the sector/block erased by the erase type
 * @opcode:	the SPI command op code to erase the sector/block
 * @i:		erase type index as sorted in the Basic Flash Parameter Table
 *
 * The supported Erase Types will be sorted at init in ascending order, with
 * the smallest Erase Type size being the first member in the erase_type array
 * of the spi_nor_erase_map structure. Save the Erase Type index as sorted in
 * the Basic Flash Parameter Table since it will be used later on to
 * synchronize with the supported Erase Types defined in SFDP optional tables.
 */
static void
spi_nor_set_erase_settings_from_bfpt(struct spi_nor_erase_type *erase,
				     u32 size, u8 opcode, u8 i)
{
	erase->idx = i;
	spi_nor_set_erase_type(erase, size, opcode);
}

/**
 * spi_nor_map_cmp_erase_type() - compare the map's erase types by size
 * @l:	member in the left half of the map's erase_type array
 * @r:	member in the right half of the map's erase_type array
 *
 * Comparison function used in the sort() call to sort in ascending order the
 * map's erase types, the smallest erase type size being the first member in the
 * sorted erase_type array.
 *
 * Return: the result of @l->size - @r->size
 */
static int spi_nor_map_cmp_erase_type(const void *l, const void *r)
{
	const struct spi_nor_erase_type *left = l, *right = r;

	return left->size - right->size;
}

/**
 * spi_nor_sort_erase_mask() - sort erase mask
 * @map:	the erase map of the SPI NOR
 * @erase_mask:	the erase type mask to be sorted
 *
 * Replicate the sort done for the map's erase types in BFPT: sort the erase
 * mask in ascending order with the smallest erase type size starting from
 * BIT(0) in the sorted erase mask.
 *
 * Return: sorted erase mask.
 */
static u8 spi_nor_sort_erase_mask(struct spi_nor_erase_map *map, u8 erase_mask)
{
	struct spi_nor_erase_type *erase_type = map->erase_type;
	int i;
	u8 sorted_erase_mask = 0;

	if (!erase_mask)
		return 0;

	/* Replicate the sort done for the map's erase types. */
	for (i = 0; i < SNOR_ERASE_TYPE_MAX; i++)
		if (erase_type[i].size && erase_mask & BIT(erase_type[i].idx))
			sorted_erase_mask |= BIT(i);

	return sorted_erase_mask;
}

/**
 * spi_nor_regions_sort_erase_types() - sort erase types in each region
 * @map:	the erase map of the SPI NOR
 *
 * Function assumes that the erase types defined in the erase map are already
 * sorted in ascending order, with the smallest erase type size being the first
 * member in the erase_type array. It replicates the sort done for the map's
 * erase types. Each region's erase bitmask will indicate which erase types are
 * supported from the sorted erase types defined in the erase map.
 * Sort the all region's erase type at init in order to speed up the process of
 * finding the best erase command at runtime.
 */
static void spi_nor_regions_sort_erase_types(struct spi_nor_erase_map *map)
{
	struct spi_nor_erase_region *region = map->regions;
	u8 region_erase_mask, sorted_erase_mask;

	while (region) {
		region_erase_mask = region->offset & SNOR_ERASE_TYPE_MASK;

		sorted_erase_mask = spi_nor_sort_erase_mask(map,
							    region_erase_mask);

		/* Overwrite erase mask. */
		region->offset = (region->offset & ~SNOR_ERASE_TYPE_MASK) |
				 sorted_erase_mask;

		region = spi_nor_region_next(region);
	}
}

/**
 * spi_nor_parse_bfpt() - read and parse the Basic Flash Parameter Table.
 * @nor:		pointer to a 'struct spi_nor'
 * @bfpt_header:	pointer to the 'struct sfdp_parameter_header' describing
 *			the Basic Flash Parameter Table length and version
 *
 * The Basic Flash Parameter Table is the main and only mandatory table as
 * defined by the SFDP (JESD216) specification.
 * It provides us with the total size (memory density) of the data array and
 * the number of address bytes for Fast Read, Page Program and Sector Erase
 * commands.
 * For Fast READ commands, it also gives the number of mode clock cycles and
 * wait states (regrouped in the number of dummy clock cycles) for each
 * supported instruction op code.
 * For Page Program, the page size is now available since JESD216 rev A, however
 * the supported instruction op codes are still not provided.
 * For Sector Erase commands, this table stores the supported instruction op
 * codes and the associated sector sizes.
 * Finally, the Quad Enable Requirements (QER) are also available since JESD216
 * rev A. The QER bits encode the manufacturer dependent procedure to be
 * executed to set the Quad Enable (QE) bit in some internal register of the
 * Quad SPI memory. Indeed the QE bit, when it exists, must be set before
 * sending any Quad SPI command to the memory. Actually, setting the QE bit
 * tells the memory to reassign its WP# and HOLD#/RESET# pins to functions IO2
 * and IO3 hence enabling 4 (Quad) I/O lines.
 *
 * Return: 0 on success, -errno otherwise.
 */
static int spi_nor_parse_bfpt(struct spi_nor *nor,
			      const struct sfdp_parameter_header *bfpt_header)
{
	struct spi_nor_flash_parameter *params = nor->params;
	struct spi_nor_erase_map *map = &params->erase_map;
	struct spi_nor_erase_type *erase_type = map->erase_type;
	struct sfdp_bfpt bfpt;
	size_t len;
	int i, cmd, err;
	u32 addr, val;
	u16 half;
	u8 erase_mask;

	/* JESD216 Basic Flash Parameter Table length is at least 9 DWORDs. */
	if (bfpt_header->length < BFPT_DWORD_MAX_JESD216)
		return -EINVAL;

	/* Read the Basic Flash Parameter Table. */
	len = min_t(size_t, sizeof(bfpt),
		    bfpt_header->length * sizeof(u32));
	addr = SFDP_PARAM_HEADER_PTP(bfpt_header);
	memset(&bfpt, 0, sizeof(bfpt));
	err = spi_nor_read_sfdp_dma_unsafe(nor,  addr, len, &bfpt);
	if (err < 0)
		return err;

	/* Fix endianness of the BFPT DWORDs. */
	le32_to_cpu_array(bfpt.dwords, BFPT_DWORD_MAX);

	/* Number of address bytes. */
	switch (bfpt.dwords[BFPT_DWORD(1)] & BFPT_DWORD1_ADDRESS_BYTES_MASK) {
	case BFPT_DWORD1_ADDRESS_BYTES_3_ONLY:
	case BFPT_DWORD1_ADDRESS_BYTES_3_OR_4:
		params->addr_nbytes = 3;
		params->addr_mode_nbytes = 3;
		break;

	case BFPT_DWORD1_ADDRESS_BYTES_4_ONLY:
		params->addr_nbytes = 4;
		params->addr_mode_nbytes = 4;
		break;

	default:
		break;
	}

	/* Flash Memory Density (in bits). */
	val = bfpt.dwords[BFPT_DWORD(2)];
	if (val & BIT(31)) {
		val &= ~BIT(31);

		/*
		 * Prevent overflows on params->size. Anyway, a NOR of 2^64
		 * bits is unlikely to exist so this error probably means
		 * the BFPT we are reading is corrupted/wrong.
		 */
		if (val > 63)
			return -EINVAL;

		params->size = 1ULL << val;
	} else {
		params->size = val + 1;
	}
	params->size >>= 3; /* Convert to bytes. */

	/* Fast Read settings. */
	for (i = 0; i < ARRAY_SIZE(sfdp_bfpt_reads); i++) {
		const struct sfdp_bfpt_read *rd = &sfdp_bfpt_reads[i];
		struct spi_nor_read_command *read;

		if (!(bfpt.dwords[rd->supported_dword] & rd->supported_bit)) {
			params->hwcaps.mask &= ~rd->hwcaps;
			continue;
		}

		params->hwcaps.mask |= rd->hwcaps;
		cmd = spi_nor_hwcaps_read2cmd(rd->hwcaps);
		read = &params->reads[cmd];
		half = bfpt.dwords[rd->settings_dword] >> rd->settings_shift;
		spi_nor_set_read_settings_from_bfpt(read, half, rd->proto);
	}

	/*
	 * Sector Erase settings. Reinitialize the uniform erase map using the
	 * Erase Types defined in the bfpt table.
	 */
	erase_mask = 0;
	memset(&params->erase_map, 0, sizeof(params->erase_map));
	for (i = 0; i < ARRAY_SIZE(sfdp_bfpt_erases); i++) {
		const struct sfdp_bfpt_erase *er = &sfdp_bfpt_erases[i];
		u32 erasesize;
		u8 opcode;

		half = bfpt.dwords[er->dword] >> er->shift;
		erasesize = half & 0xff;

		/* erasesize == 0 means this Erase Type is not supported. */
		if (!erasesize)
			continue;

		erasesize = 1U << erasesize;
		opcode = (half >> 8) & 0xff;
		erase_mask |= BIT(i);
		spi_nor_set_erase_settings_from_bfpt(&erase_type[i], erasesize,
						     opcode, i);
	}
	spi_nor_init_uniform_erase_map(map, erase_mask, params->size);
	/*
	 * Sort all the map's Erase Types in ascending order with the smallest
	 * erase size being the first member in the erase_type array.
	 */
	sort(erase_type, SNOR_ERASE_TYPE_MAX, sizeof(erase_type[0]),
	     spi_nor_map_cmp_erase_type, NULL);
	/*
	 * Sort the erase types in the uniform region in order to update the
	 * uniform_erase_type bitmask. The bitmask will be used later on when
	 * selecting the uniform erase.
	 */
	spi_nor_regions_sort_erase_types(map);
	map->uniform_erase_type = map->uniform_region.offset &
				  SNOR_ERASE_TYPE_MASK;

	/* Stop here if not JESD216 rev A or later. */
	if (bfpt_header->length == BFPT_DWORD_MAX_JESD216)
		return spi_nor_post_bfpt_fixups(nor, bfpt_header, &bfpt);

	/* Page size: this field specifies 'N' so the page size = 2^N bytes. */
	val = bfpt.dwords[BFPT_DWORD(11)];
	val &= BFPT_DWORD11_PAGE_SIZE_MASK;
	val >>= BFPT_DWORD11_PAGE_SIZE_SHIFT;
	params->page_size = 1U << val;

	/* Quad Enable Requirements. */
	switch (bfpt.dwords[BFPT_DWORD(15)] & BFPT_DWORD15_QER_MASK) {
	case BFPT_DWORD15_QER_NONE:
		params->quad_enable = NULL;
		break;

	case BFPT_DWORD15_QER_SR2_BIT1_BUGGY:
		/*
		 * Writing only one byte to the Status Register has the
		 * side-effect of clearing Status Register 2.
		 */
	case BFPT_DWORD15_QER_SR2_BIT1_NO_RD:
		/*
		 * Read Configuration Register (35h) instruction is not
		 * supported.
		 */
		nor->flags |= SNOR_F_HAS_16BIT_SR | SNOR_F_NO_READ_CR;
		params->quad_enable = spi_nor_sr2_bit1_quad_enable;
		break;

	case BFPT_DWORD15_QER_SR1_BIT6:
		nor->flags &= ~SNOR_F_HAS_16BIT_SR;
		params->quad_enable = spi_nor_sr1_bit6_quad_enable;
		break;

	case BFPT_DWORD15_QER_SR2_BIT7:
		nor->flags &= ~SNOR_F_HAS_16BIT_SR;
		params->quad_enable = spi_nor_sr2_bit7_quad_enable;
		break;

	case BFPT_DWORD15_QER_SR2_BIT1:
		/*
		 * JESD216 rev B or later does not specify if writing only one
		 * byte to the Status Register clears or not the Status
		 * Register 2, so let's be cautious and keep the default
		 * assumption of a 16-bit Write Status (01h) command.
		 */
		nor->flags |= SNOR_F_HAS_16BIT_SR;

		params->quad_enable = spi_nor_sr2_bit1_quad_enable;
		break;

	default:
		dev_dbg(nor->dev, "BFPT QER reserved value used\n");
		break;
	}

	/* Soft Reset support. */
	if (bfpt.dwords[BFPT_DWORD(16)] & BFPT_DWORD16_SWRST_EN_RST)
		nor->flags |= SNOR_F_SOFT_RESET;

	/* Stop here if not JESD216 rev C or later. */
	if (bfpt_header->length == BFPT_DWORD_MAX_JESD216B)
		return spi_nor_post_bfpt_fixups(nor, bfpt_header, &bfpt);

	/* 8D-8D-8D command extension. */
	switch (bfpt.dwords[BFPT_DWORD(18)] & BFPT_DWORD18_CMD_EXT_MASK) {
	case BFPT_DWORD18_CMD_EXT_REP:
		nor->cmd_ext_type = SPI_NOR_EXT_REPEAT;
		break;

	case BFPT_DWORD18_CMD_EXT_INV:
		nor->cmd_ext_type = SPI_NOR_EXT_INVERT;
		break;

	case BFPT_DWORD18_CMD_EXT_RES:
		dev_dbg(nor->dev, "Reserved command extension used\n");
		break;

	case BFPT_DWORD18_CMD_EXT_16B:
		dev_dbg(nor->dev, "16-bit opcodes not supported\n");
		return -EOPNOTSUPP;
	}

	return spi_nor_post_bfpt_fixups(nor, bfpt_header, &bfpt);
}

/**
 * spi_nor_smpt_addr_nbytes() - return the number of address bytes used in the
 *			       configuration detection command.
 * @nor:	pointer to a 'struct spi_nor'
 * @settings:	configuration detection command descriptor, dword1
 */
static u8 spi_nor_smpt_addr_nbytes(const struct spi_nor *nor, const u32 settings)
{
	switch (settings & SMPT_CMD_ADDRESS_LEN_MASK) {
	case SMPT_CMD_ADDRESS_LEN_0:
		return 0;
	case SMPT_CMD_ADDRESS_LEN_3:
		return 3;
	case SMPT_CMD_ADDRESS_LEN_4:
		return 4;
	case SMPT_CMD_ADDRESS_LEN_USE_CURRENT:
	default:
		return nor->params->addr_mode_nbytes;
	}
}

/**
 * spi_nor_smpt_read_dummy() - return the configuration detection command read
 *			       latency, in clock cycles.
 * @nor:	pointer to a 'struct spi_nor'
 * @settings:	configuration detection command descriptor, dword1
 *
 * Return: the number of dummy cycles for an SMPT read
 */
static u8 spi_nor_smpt_read_dummy(const struct spi_nor *nor, const u32 settings)
{
	u8 read_dummy = SMPT_CMD_READ_DUMMY(settings);

	if (read_dummy == SMPT_CMD_READ_DUMMY_IS_VARIABLE)
		return nor->read_dummy;
	return read_dummy;
}

/**
 * spi_nor_get_map_in_use() - get the configuration map in use
 * @nor:	pointer to a 'struct spi_nor'
 * @smpt:	pointer to the sector map parameter table
 * @smpt_len:	sector map parameter table length
 *
 * Return: pointer to the map in use, ERR_PTR(-errno) otherwise.
 */
static const u32 *spi_nor_get_map_in_use(struct spi_nor *nor, const u32 *smpt,
					 u8 smpt_len)
{
	const u32 *ret;
	u8 *buf;
	u32 addr;
	int err;
	u8 i;
	u8 addr_nbytes, read_opcode, read_dummy;
	u8 read_data_mask, map_id;

	/* Use a kmalloc'ed bounce buffer to guarantee it is DMA-able. */
	buf = kmalloc(sizeof(*buf), GFP_KERNEL);
	if (!buf)
		return ERR_PTR(-ENOMEM);

	addr_nbytes = nor->addr_nbytes;
	read_dummy = nor->read_dummy;
	read_opcode = nor->read_opcode;

	map_id = 0;
	/* Determine if there are any optional Detection Command Descriptors */
	for (i = 0; i < smpt_len; i += 2) {
		if (smpt[i] & SMPT_DESC_TYPE_MAP)
			break;

		read_data_mask = SMPT_CMD_READ_DATA(smpt[i]);
		nor->addr_nbytes = spi_nor_smpt_addr_nbytes(nor, smpt[i]);
		nor->read_dummy = spi_nor_smpt_read_dummy(nor, smpt[i]);
		nor->read_opcode = SMPT_CMD_OPCODE(smpt[i]);
		addr = smpt[i + 1];

		err = spi_nor_read_raw(nor, addr, 1, buf);
		if (err) {
			ret = ERR_PTR(err);
			goto out;
		}

		/*
		 * Build an index value that is used to select the Sector Map
		 * Configuration that is currently in use.
		 */
		map_id = map_id << 1 | !!(*buf & read_data_mask);
	}

	/*
	 * If command descriptors are provided, they always precede map
	 * descriptors in the table. There is no need to start the iteration
	 * over smpt array all over again.
	 *
	 * Find the matching configuration map.
	 */
	ret = ERR_PTR(-EINVAL);
	while (i < smpt_len) {
		if (SMPT_MAP_ID(smpt[i]) == map_id) {
			ret = smpt + i;
			break;
		}

		/*
		 * If there are no more configuration map descriptors and no
		 * configuration ID matched the configuration identifier, the
		 * sector address map is unknown.
		 */
		if (smpt[i] & SMPT_DESC_END)
			break;

		/* increment the table index to the next map */
		i += SMPT_MAP_REGION_COUNT(smpt[i]) + 1;
	}

	/* fall through */
out:
	kfree(buf);
	nor->addr_nbytes = addr_nbytes;
	nor->read_dummy = read_dummy;
	nor->read_opcode = read_opcode;
	return ret;
}

static void spi_nor_region_mark_end(struct spi_nor_erase_region *region)
{
	region->offset |= SNOR_LAST_REGION;
}

static void spi_nor_region_mark_overlay(struct spi_nor_erase_region *region)
{
	region->offset |= SNOR_OVERLAID_REGION;
}

/**
 * spi_nor_region_check_overlay() - set overlay bit when the region is overlaid
 * @region:	pointer to a structure that describes a SPI NOR erase region
 * @erase:	pointer to a structure that describes a SPI NOR erase type
 * @erase_type:	erase type bitmask
 */
static void
spi_nor_region_check_overlay(struct spi_nor_erase_region *region,
			     const struct spi_nor_erase_type *erase,
			     const u8 erase_type)
{
	int i;

	for (i = 0; i < SNOR_ERASE_TYPE_MAX; i++) {
		if (!(erase[i].size && erase_type & BIT(erase[i].idx)))
			continue;
		if (region->size & erase[i].size_mask) {
			spi_nor_region_mark_overlay(region);
			return;
		}
	}
}

/**
 * spi_nor_init_non_uniform_erase_map() - initialize the non-uniform erase map
 * @nor:	pointer to a 'struct spi_nor'
 * @smpt:	pointer to the sector map parameter table
 *
 * Return: 0 on success, -errno otherwise.
 */
static int spi_nor_init_non_uniform_erase_map(struct spi_nor *nor,
					      const u32 *smpt)
{
	struct spi_nor_erase_map *map = &nor->params->erase_map;
	struct spi_nor_erase_type *erase = map->erase_type;
	struct spi_nor_erase_region *region;
	u64 offset;
	u32 region_count;
	int i, j;
	u8 uniform_erase_type, save_uniform_erase_type;
	u8 erase_type, regions_erase_type;

	region_count = SMPT_MAP_REGION_COUNT(*smpt);
	/*
	 * The regions will be freed when the driver detaches from the
	 * device.
	 */
	region = devm_kcalloc(nor->dev, region_count, sizeof(*region),
			      GFP_KERNEL);
	if (!region)
		return -ENOMEM;
	map->regions = region;

	uniform_erase_type = 0xff;
	regions_erase_type = 0;
	offset = 0;
	/* Populate regions. */
	for (i = 0; i < region_count; i++) {
		j = i + 1; /* index for the region dword */
		region[i].size = SMPT_MAP_REGION_SIZE(smpt[j]);
		erase_type = SMPT_MAP_REGION_ERASE_TYPE(smpt[j]);
		region[i].offset = offset | erase_type;

		spi_nor_region_check_overlay(&region[i], erase, erase_type);

		/*
		 * Save the erase types that are supported in all regions and
		 * can erase the entire flash memory.
		 */
		uniform_erase_type &= erase_type;

		/*
		 * regions_erase_type mask will indicate all the erase types
		 * supported in this configuration map.
		 */
		regions_erase_type |= erase_type;

		offset = (region[i].offset & ~SNOR_ERASE_FLAGS_MASK) +
			 region[i].size;
	}
	spi_nor_region_mark_end(&region[i - 1]);

	save_uniform_erase_type = map->uniform_erase_type;
	map->uniform_erase_type = spi_nor_sort_erase_mask(map,
							  uniform_erase_type);

	if (!regions_erase_type) {
		/*
		 * Roll back to the previous uniform_erase_type mask, SMPT is
		 * broken.
		 */
		map->uniform_erase_type = save_uniform_erase_type;
		return -EINVAL;
	}

	/*
	 * BFPT advertises all the erase types supported by all the possible
	 * map configurations. Mask out the erase types that are not supported
	 * by the current map configuration.
	 */
	for (i = 0; i < SNOR_ERASE_TYPE_MAX; i++)
		if (!(regions_erase_type & BIT(erase[i].idx)))
			spi_nor_set_erase_type(&erase[i], 0, 0xFF);

	return 0;
}

/**
 * spi_nor_parse_smpt() - parse Sector Map Parameter Table
 * @nor:		pointer to a 'struct spi_nor'
 * @smpt_header:	sector map parameter table header
 *
 * This table is optional, but when available, we parse it to identify the
 * location and size of sectors within the main data array of the flash memory
 * device and to identify which Erase Types are supported by each sector.
 *
 * Return: 0 on success, -errno otherwise.
 */
static int spi_nor_parse_smpt(struct spi_nor *nor,
			      const struct sfdp_parameter_header *smpt_header)
{
	const u32 *sector_map;
	u32 *smpt;
	size_t len;
	u32 addr;
	int ret;

	/* Read the Sector Map Parameter Table. */
	len = smpt_header->length * sizeof(*smpt);
	smpt = kmalloc(len, GFP_KERNEL);
	if (!smpt)
		return -ENOMEM;

	addr = SFDP_PARAM_HEADER_PTP(smpt_header);
	ret = spi_nor_read_sfdp(nor, addr, len, smpt);
	if (ret)
		goto out;

	/* Fix endianness of the SMPT DWORDs. */
	le32_to_cpu_array(smpt, smpt_header->length);

	sector_map = spi_nor_get_map_in_use(nor, smpt, smpt_header->length);
	if (IS_ERR(sector_map)) {
		ret = PTR_ERR(sector_map);
		goto out;
	}

	ret = spi_nor_init_non_uniform_erase_map(nor, sector_map);
	if (ret)
		goto out;

	spi_nor_regions_sort_erase_types(&nor->params->erase_map);
	/* fall through */
out:
	kfree(smpt);
	return ret;
}

/**
 * spi_nor_parse_4bait() - parse the 4-Byte Address Instruction Table
 * @nor:		pointer to a 'struct spi_nor'.
 * @param_header:	pointer to the 'struct sfdp_parameter_header' describing
 *			the 4-Byte Address Instruction Table length and version.
 *
 * Return: 0 on success, -errno otherwise.
 */
static int spi_nor_parse_4bait(struct spi_nor *nor,
			       const struct sfdp_parameter_header *param_header)
{
	static const struct sfdp_4bait reads[] = {
		{ SNOR_HWCAPS_READ,		BIT(0) },
		{ SNOR_HWCAPS_READ_FAST,	BIT(1) },
		{ SNOR_HWCAPS_READ_1_1_2,	BIT(2) },
		{ SNOR_HWCAPS_READ_1_2_2,	BIT(3) },
		{ SNOR_HWCAPS_READ_1_1_4,	BIT(4) },
		{ SNOR_HWCAPS_READ_1_4_4,	BIT(5) },
		{ SNOR_HWCAPS_READ_1_1_1_DTR,	BIT(13) },
		{ SNOR_HWCAPS_READ_1_2_2_DTR,	BIT(14) },
		{ SNOR_HWCAPS_READ_1_4_4_DTR,	BIT(15) },
	};
	static const struct sfdp_4bait programs[] = {
		{ SNOR_HWCAPS_PP,		BIT(6) },
		{ SNOR_HWCAPS_PP_1_1_4,		BIT(7) },
		{ SNOR_HWCAPS_PP_1_4_4,		BIT(8) },
	};
	static const struct sfdp_4bait erases[SNOR_ERASE_TYPE_MAX] = {
		{ 0u /* not used */,		BIT(9) },
		{ 0u /* not used */,		BIT(10) },
		{ 0u /* not used */,		BIT(11) },
		{ 0u /* not used */,		BIT(12) },
	};
	struct spi_nor_flash_parameter *params = nor->params;
	struct spi_nor_pp_command *params_pp = params->page_programs;
	struct spi_nor_erase_map *map = &params->erase_map;
	struct spi_nor_erase_type *erase_type = map->erase_type;
	u32 *dwords;
	size_t len;
	u32 addr, discard_hwcaps, read_hwcaps, pp_hwcaps, erase_mask;
	int i, ret;

	if (param_header->major != SFDP_JESD216_MAJOR ||
	    param_header->length < SFDP_4BAIT_DWORD_MAX)
		return -EINVAL;

	/* Read the 4-byte Address Instruction Table. */
	len = sizeof(*dwords) * SFDP_4BAIT_DWORD_MAX;

	/* Use a kmalloc'ed bounce buffer to guarantee it is DMA-able. */
	dwords = kmalloc(len, GFP_KERNEL);
	if (!dwords)
		return -ENOMEM;

	addr = SFDP_PARAM_HEADER_PTP(param_header);
	ret = spi_nor_read_sfdp(nor, addr, len, dwords);
	if (ret)
		goto out;

	/* Fix endianness of the 4BAIT DWORDs. */
	le32_to_cpu_array(dwords, SFDP_4BAIT_DWORD_MAX);

	/*
	 * Compute the subset of (Fast) Read commands for which the 4-byte
	 * version is supported.
	 */
	discard_hwcaps = 0;
	read_hwcaps = 0;
	for (i = 0; i < ARRAY_SIZE(reads); i++) {
		const struct sfdp_4bait *read = &reads[i];

		discard_hwcaps |= read->hwcaps;
		if ((params->hwcaps.mask & read->hwcaps) &&
		    (dwords[0] & read->supported_bit))
			read_hwcaps |= read->hwcaps;
	}

	/*
	 * Compute the subset of Page Program commands for which the 4-byte
	 * version is supported.
	 */
	pp_hwcaps = 0;
	for (i = 0; i < ARRAY_SIZE(programs); i++) {
		const struct sfdp_4bait *program = &programs[i];

		/*
		 * The 4 Byte Address Instruction (Optional) Table is the only
		 * SFDP table that indicates support for Page Program Commands.
		 * Bypass the params->hwcaps.mask and consider 4BAIT the biggest
		 * authority for specifying Page Program support.
		 */
		discard_hwcaps |= program->hwcaps;
		if (dwords[0] & program->supported_bit)
			pp_hwcaps |= program->hwcaps;
	}

	/*
	 * Compute the subset of Sector Erase commands for which the 4-byte
	 * version is supported.
	 */
	erase_mask = 0;
	for (i = 0; i < SNOR_ERASE_TYPE_MAX; i++) {
		const struct sfdp_4bait *erase = &erases[i];

		if (dwords[0] & erase->supported_bit)
			erase_mask |= BIT(i);
	}

	/* Replicate the sort done for the map's erase types in BFPT. */
	erase_mask = spi_nor_sort_erase_mask(map, erase_mask);

	/*
	 * We need at least one 4-byte op code per read, program and erase
	 * operation; the .read(), .write() and .erase() hooks share the
	 * nor->addr_nbytes value.
	 */
	if (!read_hwcaps || !pp_hwcaps || !erase_mask)
		goto out;

	/*
	 * Discard all operations from the 4-byte instruction set which are
	 * not supported by this memory.
	 */
	params->hwcaps.mask &= ~discard_hwcaps;
	params->hwcaps.mask |= (read_hwcaps | pp_hwcaps);

	/* Use the 4-byte address instruction set. */
	for (i = 0; i < SNOR_CMD_READ_MAX; i++) {
		struct spi_nor_read_command *read_cmd = &params->reads[i];

		read_cmd->opcode = spi_nor_convert_3to4_read(read_cmd->opcode);
	}

	/* 4BAIT is the only SFDP table that indicates page program support. */
	if (pp_hwcaps & SNOR_HWCAPS_PP) {
		spi_nor_set_pp_settings(&params_pp[SNOR_CMD_PP],
					SPINOR_OP_PP_4B, SNOR_PROTO_1_1_1);
		/*
		 * Since xSPI Page Program opcode is backward compatible with
		 * Legacy SPI, use Legacy SPI opcode there as well.
		 */
		spi_nor_set_pp_settings(&params_pp[SNOR_CMD_PP_8_8_8_DTR],
					SPINOR_OP_PP_4B, SNOR_PROTO_8_8_8_DTR);
	}
	if (pp_hwcaps & SNOR_HWCAPS_PP_1_1_4)
		spi_nor_set_pp_settings(&params_pp[SNOR_CMD_PP_1_1_4],
					SPINOR_OP_PP_1_1_4_4B,
					SNOR_PROTO_1_1_4);
	if (pp_hwcaps & SNOR_HWCAPS_PP_1_4_4)
		spi_nor_set_pp_settings(&params_pp[SNOR_CMD_PP_1_4_4],
					SPINOR_OP_PP_1_4_4_4B,
					SNOR_PROTO_1_4_4);

	for (i = 0; i < SNOR_ERASE_TYPE_MAX; i++) {
		if (erase_mask & BIT(i))
			erase_type[i].opcode = (dwords[1] >>
						erase_type[i].idx * 8) & 0xFF;
		else
			spi_nor_set_erase_type(&erase_type[i], 0u, 0xFF);
	}

	/*
	 * We set SNOR_F_HAS_4BAIT in order to skip spi_nor_set_4byte_opcodes()
	 * later because we already did the conversion to 4byte opcodes. Also,
	 * this latest function implements a legacy quirk for the erase size of
	 * Spansion memory. However this quirk is no longer needed with new
	 * SFDP compliant memories.
	 */
	params->addr_nbytes = 4;
	nor->flags |= SNOR_F_4B_OPCODES | SNOR_F_HAS_4BAIT;

	/* fall through */
out:
	kfree(dwords);
	return ret;
}

#define PROFILE1_DWORD1_RDSR_ADDR_BYTES		BIT(29)
#define PROFILE1_DWORD1_RDSR_DUMMY		BIT(28)
#define PROFILE1_DWORD1_RD_FAST_CMD		GENMASK(15, 8)
#define PROFILE1_DWORD4_DUMMY_200MHZ		GENMASK(11, 7)
#define PROFILE1_DWORD5_DUMMY_166MHZ		GENMASK(31, 27)
#define PROFILE1_DWORD5_DUMMY_133MHZ		GENMASK(21, 17)
#define PROFILE1_DWORD5_DUMMY_100MHZ		GENMASK(11, 7)

/**
 * spi_nor_parse_profile1() - parse the xSPI Profile 1.0 table
 * @nor:		pointer to a 'struct spi_nor'
 * @profile1_header:	pointer to the 'struct sfdp_parameter_header' describing
 *			the Profile 1.0 Table length and version.
 *
 * Return: 0 on success, -errno otherwise.
 */
static int spi_nor_parse_profile1(struct spi_nor *nor,
				  const struct sfdp_parameter_header *profile1_header)
{
	u32 *dwords, addr;
	size_t len;
	int ret;
	u8 dummy, opcode;

	len = profile1_header->length * sizeof(*dwords);
	dwords = kmalloc(len, GFP_KERNEL);
	if (!dwords)
		return -ENOMEM;

	addr = SFDP_PARAM_HEADER_PTP(profile1_header);
	ret = spi_nor_read_sfdp(nor, addr, len, dwords);
	if (ret)
		goto out;

	le32_to_cpu_array(dwords, profile1_header->length);

	/* Get 8D-8D-8D fast read opcode and dummy cycles. */
	opcode = FIELD_GET(PROFILE1_DWORD1_RD_FAST_CMD, dwords[0]);

	 /* Set the Read Status Register dummy cycles and dummy address bytes. */
	if (dwords[0] & PROFILE1_DWORD1_RDSR_DUMMY)
		nor->params->rdsr_dummy = 8;
	else
		nor->params->rdsr_dummy = 4;

	if (dwords[0] & PROFILE1_DWORD1_RDSR_ADDR_BYTES)
		nor->params->rdsr_addr_nbytes = 4;
	else
		nor->params->rdsr_addr_nbytes = 0;

	/*
	 * We don't know what speed the controller is running at. Find the
	 * dummy cycles for the fastest frequency the flash can run at to be
	 * sure we are never short of dummy cycles. A value of 0 means the
	 * frequency is not supported.
	 *
	 * Default to PROFILE1_DUMMY_DEFAULT if we don't find anything, and let
	 * flashes set the correct value if needed in their fixup hooks.
	 */
	dummy = FIELD_GET(PROFILE1_DWORD4_DUMMY_200MHZ, dwords[3]);
	if (!dummy)
		dummy = FIELD_GET(PROFILE1_DWORD5_DUMMY_166MHZ, dwords[4]);
	if (!dummy)
		dummy = FIELD_GET(PROFILE1_DWORD5_DUMMY_133MHZ, dwords[4]);
	if (!dummy)
		dummy = FIELD_GET(PROFILE1_DWORD5_DUMMY_100MHZ, dwords[4]);
	if (!dummy)
		dev_dbg(nor->dev,
			"Can't find dummy cycles from Profile 1.0 table\n");

	/* Round up to an even value to avoid tripping controllers up. */
	dummy = round_up(dummy, 2);

	/* Update the fast read settings. */
	spi_nor_set_read_settings(&nor->params->reads[SNOR_CMD_READ_8_8_8_DTR],
				  0, dummy, opcode,
				  SNOR_PROTO_8_8_8_DTR);

out:
	kfree(dwords);
	return ret;
}

#define SCCR_DWORD22_OCTAL_DTR_EN_VOLATILE		BIT(31)

/**
 * spi_nor_parse_sccr() - Parse the Status, Control and Configuration Register
 *                        Map.
 * @nor:		pointer to a 'struct spi_nor'
 * @sccr_header:	pointer to the 'struct sfdp_parameter_header' describing
 *			the SCCR Map table length and version.
 *
 * Return: 0 on success, -errno otherwise.
 */
static int spi_nor_parse_sccr(struct spi_nor *nor,
			      const struct sfdp_parameter_header *sccr_header)
{
	u32 *dwords, addr;
	size_t len;
	int ret;

	len = sccr_header->length * sizeof(*dwords);
	dwords = kmalloc(len, GFP_KERNEL);
	if (!dwords)
		return -ENOMEM;

	addr = SFDP_PARAM_HEADER_PTP(sccr_header);
	ret = spi_nor_read_sfdp(nor, addr, len, dwords);
	if (ret)
		goto out;

	le32_to_cpu_array(dwords, sccr_header->length);

	if (FIELD_GET(SCCR_DWORD22_OCTAL_DTR_EN_VOLATILE, dwords[22]))
		nor->flags |= SNOR_F_IO_MODE_EN_VOLATILE;

out:
	kfree(dwords);
	return ret;
}

/**
 * spi_nor_post_sfdp_fixups() - Updates the flash's parameters and settings
 * after SFDP has been parsed. Called only for flashes that define JESD216 SFDP
 * tables.
 * @nor:	pointer to a 'struct spi_nor'
 *
 * Used to tweak various flash parameters when information provided by the SFDP
 * tables are wrong.
 */
static void spi_nor_post_sfdp_fixups(struct spi_nor *nor)
{
	if (nor->manufacturer && nor->manufacturer->fixups &&
	    nor->manufacturer->fixups->post_sfdp)
		nor->manufacturer->fixups->post_sfdp(nor);

	if (nor->info->fixups && nor->info->fixups->post_sfdp)
		nor->info->fixups->post_sfdp(nor);
}

/**
 * spi_nor_parse_sfdp() - parse the Serial Flash Discoverable Parameters.
 * @nor:		pointer to a 'struct spi_nor'
 *
 * The Serial Flash Discoverable Parameters are described by the JEDEC JESD216
 * specification. This is a standard which tends to supported by almost all
 * (Q)SPI memory manufacturers. Those hard-coded tables allow us to learn at
 * runtime the main parameters needed to perform basic SPI flash operations such
 * as Fast Read, Page Program or Sector Erase commands.
 *
 * Return: 0 on success, -errno otherwise.
 */
int spi_nor_parse_sfdp(struct spi_nor *nor)
{
	const struct sfdp_parameter_header *param_header, *bfpt_header;
	struct sfdp_parameter_header *param_headers = NULL;
	struct sfdp_header header;
	struct device *dev = nor->dev;
	struct sfdp *sfdp;
	size_t sfdp_size;
	size_t psize;
	int i, err;

	/* Get the SFDP header. */
	err = spi_nor_read_sfdp_dma_unsafe(nor, 0, sizeof(header), &header);
	if (err < 0)
		return err;

	/* Check the SFDP header version. */
	if (le32_to_cpu(header.signature) != SFDP_SIGNATURE ||
	    header.major != SFDP_JESD216_MAJOR)
		return -EINVAL;

	/*
	 * Verify that the first and only mandatory parameter header is a
	 * Basic Flash Parameter Table header as specified in JESD216.
	 */
	bfpt_header = &header.bfpt_header;
	if (SFDP_PARAM_HEADER_ID(bfpt_header) != SFDP_BFPT_ID ||
	    bfpt_header->major != SFDP_JESD216_MAJOR)
		return -EINVAL;

	sfdp_size = SFDP_PARAM_HEADER_PTP(bfpt_header) +
		    SFDP_PARAM_HEADER_PARAM_LEN(bfpt_header);

	/*
	 * Allocate memory then read all parameter headers with a single
	 * Read SFDP command. These parameter headers will actually be parsed
	 * twice: a first time to get the latest revision of the basic flash
	 * parameter table, then a second time to handle the supported optional
	 * tables.
	 * Hence we read the parameter headers once for all to reduce the
	 * processing time. Also we use kmalloc() instead of devm_kmalloc()
	 * because we don't need to keep these parameter headers: the allocated
	 * memory is always released with kfree() before exiting this function.
	 */
	if (header.nph) {
		psize = header.nph * sizeof(*param_headers);

		param_headers = kmalloc(psize, GFP_KERNEL);
		if (!param_headers)
			return -ENOMEM;

		err = spi_nor_read_sfdp(nor, sizeof(header),
					psize, param_headers);
		if (err < 0) {
			dev_dbg(dev, "failed to read SFDP parameter headers\n");
			goto exit;
		}
	}

	/*
	 * Cache the complete SFDP data. It is not (easily) possible to fetch
	 * SFDP after probe time and we need it for the sysfs access.
	 */
	for (i = 0; i < header.nph; i++) {
		param_header = &param_headers[i];
		sfdp_size = max_t(size_t, sfdp_size,
				  SFDP_PARAM_HEADER_PTP(param_header) +
				  SFDP_PARAM_HEADER_PARAM_LEN(param_header));
	}

	/*
	 * Limit the total size to a reasonable value to avoid allocating too
	 * much memory just of because the flash returned some insane values.
	 */
	if (sfdp_size > PAGE_SIZE) {
		dev_dbg(dev, "SFDP data (%zu) too big, truncating\n",
			sfdp_size);
		sfdp_size = PAGE_SIZE;
	}

	sfdp = devm_kzalloc(dev, sizeof(*sfdp), GFP_KERNEL);
	if (!sfdp) {
		err = -ENOMEM;
		goto exit;
	}

	/*
	 * The SFDP is organized in chunks of DWORDs. Thus, in theory, the
	 * sfdp_size should be a multiple of DWORDs. But in case a flash
	 * is not spec compliant, make sure that we have enough space to store
	 * the complete SFDP data.
	 */
	sfdp->num_dwords = DIV_ROUND_UP(sfdp_size, sizeof(*sfdp->dwords));
	sfdp->dwords = devm_kcalloc(dev, sfdp->num_dwords,
				    sizeof(*sfdp->dwords), GFP_KERNEL);
	if (!sfdp->dwords) {
		err = -ENOMEM;
		devm_kfree(dev, sfdp);
		goto exit;
	}

	err = spi_nor_read_sfdp(nor, 0, sfdp_size, sfdp->dwords);
	if (err < 0) {
		dev_dbg(dev, "failed to read SFDP data\n");
		devm_kfree(dev, sfdp->dwords);
		devm_kfree(dev, sfdp);
		goto exit;
	}

	nor->sfdp = sfdp;

	/*
	 * Check other parameter headers to get the latest revision of
	 * the basic flash parameter table.
	 */
	for (i = 0; i < header.nph; i++) {
		param_header = &param_headers[i];

		if (SFDP_PARAM_HEADER_ID(param_header) == SFDP_BFPT_ID &&
		    param_header->major == SFDP_JESD216_MAJOR &&
		    (param_header->minor > bfpt_header->minor ||
		     (param_header->minor == bfpt_header->minor &&
		      param_header->length > bfpt_header->length)))
			bfpt_header = param_header;
	}

	err = spi_nor_parse_bfpt(nor, bfpt_header);
	if (err)
		goto exit;

	/* Parse optional parameter tables. */
	for (i = 0; i < header.nph; i++) {
		param_header = &param_headers[i];

		switch (SFDP_PARAM_HEADER_ID(param_header)) {
		case SFDP_SECTOR_MAP_ID:
			err = spi_nor_parse_smpt(nor, param_header);
			break;

		case SFDP_4BAIT_ID:
			err = spi_nor_parse_4bait(nor, param_header);
			break;

		case SFDP_PROFILE1_ID:
			err = spi_nor_parse_profile1(nor, param_header);
			break;

		case SFDP_SCCR_MAP_ID:
			err = spi_nor_parse_sccr(nor, param_header);
			break;

		default:
			break;
		}

		if (err) {
			dev_warn(dev, "Failed to parse optional parameter table: %04x\n",
				 SFDP_PARAM_HEADER_ID(param_header));
			/*
			 * Let's not drop all information we extracted so far
			 * if optional table parsers fail. In case of failing,
			 * each optional parser is responsible to roll back to
			 * the previously known spi_nor data.
			 */
			err = 0;
		}
	}

	spi_nor_post_sfdp_fixups(nor);
exit:
	kfree(param_headers);
	return err;
}