summaryrefslogtreecommitdiffstats
path: root/arch/arm/mach-omap2/gpmc.c
blob: 9f42d5437fcc52e6cb3693f5dbbab18b29c6aebf (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
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
/*
 * GPMC support functions
 *
 * Copyright (C) 2005-2006 Nokia Corporation
 *
 * Author: Juha Yrjola
 *
 * Copyright (C) 2009 Texas Instruments
 * Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.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.
 */
#undef DEBUG

#include <linux/irq.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/err.h>
#include <linux/clk.h>
#include <linux/ioport.h>
#include <linux/spinlock.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_mtd.h>
#include <linux/of_device.h>
#include <linux/mtd/nand.h>
#include <linux/pm_runtime.h>

#include <linux/platform_data/mtd-nand-omap2.h>

#include <asm/mach-types.h>

#include "soc.h"
#include "common.h"
#include "omap_device.h"
#include "gpmc.h"
#include "gpmc-nand.h"
#include "gpmc-onenand.h"

#define	DEVICE_NAME		"omap-gpmc"

/* GPMC register offsets */
#define GPMC_REVISION		0x00
#define GPMC_SYSCONFIG		0x10
#define GPMC_SYSSTATUS		0x14
#define GPMC_IRQSTATUS		0x18
#define GPMC_IRQENABLE		0x1c
#define GPMC_TIMEOUT_CONTROL	0x40
#define GPMC_ERR_ADDRESS	0x44
#define GPMC_ERR_TYPE		0x48
#define GPMC_CONFIG		0x50
#define GPMC_STATUS		0x54
#define GPMC_PREFETCH_CONFIG1	0x1e0
#define GPMC_PREFETCH_CONFIG2	0x1e4
#define GPMC_PREFETCH_CONTROL	0x1ec
#define GPMC_PREFETCH_STATUS	0x1f0
#define GPMC_ECC_CONFIG		0x1f4
#define GPMC_ECC_CONTROL	0x1f8
#define GPMC_ECC_SIZE_CONFIG	0x1fc
#define GPMC_ECC1_RESULT        0x200
#define GPMC_ECC_BCH_RESULT_0   0x240   /* not available on OMAP2 */
#define	GPMC_ECC_BCH_RESULT_1	0x244	/* not available on OMAP2 */
#define	GPMC_ECC_BCH_RESULT_2	0x248	/* not available on OMAP2 */
#define	GPMC_ECC_BCH_RESULT_3	0x24c	/* not available on OMAP2 */
#define	GPMC_ECC_BCH_RESULT_4	0x300	/* not available on OMAP2 */
#define	GPMC_ECC_BCH_RESULT_5	0x304	/* not available on OMAP2 */
#define	GPMC_ECC_BCH_RESULT_6	0x308	/* not available on OMAP2 */

/* GPMC ECC control settings */
#define GPMC_ECC_CTRL_ECCCLEAR		0x100
#define GPMC_ECC_CTRL_ECCDISABLE	0x000
#define GPMC_ECC_CTRL_ECCREG1		0x001
#define GPMC_ECC_CTRL_ECCREG2		0x002
#define GPMC_ECC_CTRL_ECCREG3		0x003
#define GPMC_ECC_CTRL_ECCREG4		0x004
#define GPMC_ECC_CTRL_ECCREG5		0x005
#define GPMC_ECC_CTRL_ECCREG6		0x006
#define GPMC_ECC_CTRL_ECCREG7		0x007
#define GPMC_ECC_CTRL_ECCREG8		0x008
#define GPMC_ECC_CTRL_ECCREG9		0x009

#define	GPMC_CONFIG2_CSEXTRADELAY		BIT(7)
#define	GPMC_CONFIG3_ADVEXTRADELAY		BIT(7)
#define	GPMC_CONFIG4_OEEXTRADELAY		BIT(7)
#define	GPMC_CONFIG4_WEEXTRADELAY		BIT(23)
#define	GPMC_CONFIG6_CYCLE2CYCLEDIFFCSEN	BIT(6)
#define	GPMC_CONFIG6_CYCLE2CYCLESAMECSEN	BIT(7)

#define GPMC_CS0_OFFSET		0x60
#define GPMC_CS_SIZE		0x30
#define	GPMC_BCH_SIZE		0x10

#define GPMC_MEM_END		0x3FFFFFFF

#define GPMC_CHUNK_SHIFT	24		/* 16 MB */
#define GPMC_SECTION_SHIFT	28		/* 128 MB */

#define CS_NUM_SHIFT		24
#define ENABLE_PREFETCH		(0x1 << 7)
#define DMA_MPU_MODE		2

#define	GPMC_REVISION_MAJOR(l)		((l >> 4) & 0xf)
#define	GPMC_REVISION_MINOR(l)		(l & 0xf)

#define	GPMC_HAS_WR_ACCESS		0x1
#define	GPMC_HAS_WR_DATA_MUX_BUS	0x2
#define	GPMC_HAS_MUX_AAD		0x4

#define GPMC_NR_WAITPINS		4

/* XXX: Only NAND irq has been considered,currently these are the only ones used
 */
#define	GPMC_NR_IRQ		2

struct gpmc_client_irq	{
	unsigned		irq;
	u32			bitmask;
};

/* Structure to save gpmc cs context */
struct gpmc_cs_config {
	u32 config1;
	u32 config2;
	u32 config3;
	u32 config4;
	u32 config5;
	u32 config6;
	u32 config7;
	int is_valid;
};

/*
 * Structure to save/restore gpmc context
 * to support core off on OMAP3
 */
struct omap3_gpmc_regs {
	u32 sysconfig;
	u32 irqenable;
	u32 timeout_ctrl;
	u32 config;
	u32 prefetch_config1;
	u32 prefetch_config2;
	u32 prefetch_control;
	struct gpmc_cs_config cs_context[GPMC_CS_NUM];
};

static struct gpmc_client_irq gpmc_client_irq[GPMC_NR_IRQ];
static struct irq_chip gpmc_irq_chip;
static int gpmc_irq_start;

static struct resource	gpmc_mem_root;
static struct resource	gpmc_cs_mem[GPMC_CS_NUM];
static DEFINE_SPINLOCK(gpmc_mem_lock);
/* Define chip-selects as reserved by default until probe completes */
static unsigned int gpmc_cs_map = ((1 << GPMC_CS_NUM) - 1);
static unsigned int gpmc_cs_num = GPMC_CS_NUM;
static unsigned int gpmc_nr_waitpins;
static struct device *gpmc_dev;
static int gpmc_irq;
static resource_size_t phys_base, mem_size;
static unsigned gpmc_capability;
static void __iomem *gpmc_base;

static struct clk *gpmc_l3_clk;

static irqreturn_t gpmc_handle_irq(int irq, void *dev);

static void gpmc_write_reg(int idx, u32 val)
{
	writel_relaxed(val, gpmc_base + idx);
}

static u32 gpmc_read_reg(int idx)
{
	return readl_relaxed(gpmc_base + idx);
}

void gpmc_cs_write_reg(int cs, int idx, u32 val)
{
	void __iomem *reg_addr;

	reg_addr = gpmc_base + GPMC_CS0_OFFSET + (cs * GPMC_CS_SIZE) + idx;
	writel_relaxed(val, reg_addr);
}

static u32 gpmc_cs_read_reg(int cs, int idx)
{
	void __iomem *reg_addr;

	reg_addr = gpmc_base + GPMC_CS0_OFFSET + (cs * GPMC_CS_SIZE) + idx;
	return readl_relaxed(reg_addr);
}

/* TODO: Add support for gpmc_fck to clock framework and use it */
static unsigned long gpmc_get_fclk_period(void)
{
	unsigned long rate = clk_get_rate(gpmc_l3_clk);

	if (rate == 0) {
		printk(KERN_WARNING "gpmc_l3_clk not enabled\n");
		return 0;
	}

	rate /= 1000;
	rate = 1000000000 / rate;	/* In picoseconds */

	return rate;
}

static unsigned int gpmc_ns_to_ticks(unsigned int time_ns)
{
	unsigned long tick_ps;

	/* Calculate in picosecs to yield more exact results */
	tick_ps = gpmc_get_fclk_period();

	return (time_ns * 1000 + tick_ps - 1) / tick_ps;
}

static unsigned int gpmc_ps_to_ticks(unsigned int time_ps)
{
	unsigned long tick_ps;

	/* Calculate in picosecs to yield more exact results */
	tick_ps = gpmc_get_fclk_period();

	return (time_ps + tick_ps - 1) / tick_ps;
}

unsigned int gpmc_ticks_to_ns(unsigned int ticks)
{
	return ticks * gpmc_get_fclk_period() / 1000;
}

static unsigned int gpmc_ticks_to_ps(unsigned int ticks)
{
	return ticks * gpmc_get_fclk_period();
}

static unsigned int gpmc_round_ps_to_ticks(unsigned int time_ps)
{
	unsigned long ticks = gpmc_ps_to_ticks(time_ps);

	return ticks * gpmc_get_fclk_period();
}

static inline void gpmc_cs_modify_reg(int cs, int reg, u32 mask, bool value)
{
	u32 l;

	l = gpmc_cs_read_reg(cs, reg);
	if (value)
		l |= mask;
	else
		l &= ~mask;
	gpmc_cs_write_reg(cs, reg, l);
}

static void gpmc_cs_bool_timings(int cs, const struct gpmc_bool_timings *p)
{
	gpmc_cs_modify_reg(cs, GPMC_CS_CONFIG1,
			   GPMC_CONFIG1_TIME_PARA_GRAN,
			   p->time_para_granularity);
	gpmc_cs_modify_reg(cs, GPMC_CS_CONFIG2,
			   GPMC_CONFIG2_CSEXTRADELAY, p->cs_extra_delay);
	gpmc_cs_modify_reg(cs, GPMC_CS_CONFIG3,
			   GPMC_CONFIG3_ADVEXTRADELAY, p->adv_extra_delay);
	gpmc_cs_modify_reg(cs, GPMC_CS_CONFIG4,
			   GPMC_CONFIG4_OEEXTRADELAY, p->oe_extra_delay);
	gpmc_cs_modify_reg(cs, GPMC_CS_CONFIG4,
			   GPMC_CONFIG4_OEEXTRADELAY, p->we_extra_delay);
	gpmc_cs_modify_reg(cs, GPMC_CS_CONFIG6,
			   GPMC_CONFIG6_CYCLE2CYCLESAMECSEN,
			   p->cycle2cyclesamecsen);
	gpmc_cs_modify_reg(cs, GPMC_CS_CONFIG6,
			   GPMC_CONFIG6_CYCLE2CYCLEDIFFCSEN,
			   p->cycle2cyclediffcsen);
}

#ifdef DEBUG
static int set_gpmc_timing_reg(int cs, int reg, int st_bit, int end_bit,
			       int time, const char *name)
#else
static int set_gpmc_timing_reg(int cs, int reg, int st_bit, int end_bit,
			       int time)
#endif
{
	u32 l;
	int ticks, mask, nr_bits;

	if (time == 0)
		ticks = 0;
	else
		ticks = gpmc_ns_to_ticks(time);
	nr_bits = end_bit - st_bit + 1;
	if (ticks >= 1 << nr_bits) {
#ifdef DEBUG
		printk(KERN_INFO "GPMC CS%d: %-10s* %3d ns, %3d ticks >= %d\n",
				cs, name, time, ticks, 1 << nr_bits);
#endif
		return -1;
	}

	mask = (1 << nr_bits) - 1;
	l = gpmc_cs_read_reg(cs, reg);
#ifdef DEBUG
	printk(KERN_INFO
		"GPMC CS%d: %-10s: %3d ticks, %3lu ns (was %3i ticks) %3d ns\n",
	       cs, name, ticks, gpmc_get_fclk_period() * ticks / 1000,
			(l >> st_bit) & mask, time);
#endif
	l &= ~(mask << st_bit);
	l |= ticks << st_bit;
	gpmc_cs_write_reg(cs, reg, l);

	return 0;
}

#ifdef DEBUG
#define GPMC_SET_ONE(reg, st, end, field) \
	if (set_gpmc_timing_reg(cs, (reg), (st), (end),		\
			t->field, #field) < 0)			\
		return -1
#else
#define GPMC_SET_ONE(reg, st, end, field) \
	if (set_gpmc_timing_reg(cs, (reg), (st), (end), t->field) < 0) \
		return -1
#endif

int gpmc_calc_divider(unsigned int sync_clk)
{
	int div;
	u32 l;

	l = sync_clk + (gpmc_get_fclk_period() - 1);
	div = l / gpmc_get_fclk_period();
	if (div > 4)
		return -1;
	if (div <= 0)
		div = 1;

	return div;
}

int gpmc_cs_set_timings(int cs, const struct gpmc_timings *t)
{
	int div;
	u32 l;

	div = gpmc_calc_divider(t->sync_clk);
	if (div < 0)
		return div;

	GPMC_SET_ONE(GPMC_CS_CONFIG2,  0,  3, cs_on);
	GPMC_SET_ONE(GPMC_CS_CONFIG2,  8, 12, cs_rd_off);
	GPMC_SET_ONE(GPMC_CS_CONFIG2, 16, 20, cs_wr_off);

	GPMC_SET_ONE(GPMC_CS_CONFIG3,  0,  3, adv_on);
	GPMC_SET_ONE(GPMC_CS_CONFIG3,  8, 12, adv_rd_off);
	GPMC_SET_ONE(GPMC_CS_CONFIG3, 16, 20, adv_wr_off);

	GPMC_SET_ONE(GPMC_CS_CONFIG4,  0,  3, oe_on);
	GPMC_SET_ONE(GPMC_CS_CONFIG4,  8, 12, oe_off);
	GPMC_SET_ONE(GPMC_CS_CONFIG4, 16, 19, we_on);
	GPMC_SET_ONE(GPMC_CS_CONFIG4, 24, 28, we_off);

	GPMC_SET_ONE(GPMC_CS_CONFIG5,  0,  4, rd_cycle);
	GPMC_SET_ONE(GPMC_CS_CONFIG5,  8, 12, wr_cycle);
	GPMC_SET_ONE(GPMC_CS_CONFIG5, 16, 20, access);

	GPMC_SET_ONE(GPMC_CS_CONFIG5, 24, 27, page_burst_access);

	GPMC_SET_ONE(GPMC_CS_CONFIG6, 0, 3, bus_turnaround);
	GPMC_SET_ONE(GPMC_CS_CONFIG6, 8, 11, cycle2cycle_delay);

	GPMC_SET_ONE(GPMC_CS_CONFIG1, 18, 19, wait_monitoring);
	GPMC_SET_ONE(GPMC_CS_CONFIG1, 25, 26, clk_activation);

	if (gpmc_capability & GPMC_HAS_WR_DATA_MUX_BUS)
		GPMC_SET_ONE(GPMC_CS_CONFIG6, 16, 19, wr_data_mux_bus);
	if (gpmc_capability & GPMC_HAS_WR_ACCESS)
		GPMC_SET_ONE(GPMC_CS_CONFIG6, 24, 28, wr_access);

	/* caller is expected to have initialized CONFIG1 to cover
	 * at least sync vs async
	 */
	l = gpmc_cs_read_reg(cs, GPMC_CS_CONFIG1);
	if (l & (GPMC_CONFIG1_READTYPE_SYNC | GPMC_CONFIG1_WRITETYPE_SYNC)) {
#ifdef DEBUG
		printk(KERN_INFO "GPMC CS%d CLK period is %lu ns (div %d)\n",
				cs, (div * gpmc_get_fclk_period()) / 1000, div);
#endif
		l &= ~0x03;
		l |= (div - 1);
		gpmc_cs_write_reg(cs, GPMC_CS_CONFIG1, l);
	}

	gpmc_cs_bool_timings(cs, &t->bool_timings);

	return 0;
}

static int gpmc_cs_enable_mem(int cs, u32 base, u32 size)
{
	u32 l;
	u32 mask;

	/*
	 * Ensure that base address is aligned on a
	 * boundary equal to or greater than size.
	 */
	if (base & (size - 1))
		return -EINVAL;

	mask = (1 << GPMC_SECTION_SHIFT) - size;
	l = gpmc_cs_read_reg(cs, GPMC_CS_CONFIG7);
	l &= ~0x3f;
	l = (base >> GPMC_CHUNK_SHIFT) & 0x3f;
	l &= ~(0x0f << 8);
	l |= ((mask >> GPMC_CHUNK_SHIFT) & 0x0f) << 8;
	l |= GPMC_CONFIG7_CSVALID;
	gpmc_cs_write_reg(cs, GPMC_CS_CONFIG7, l);

	return 0;
}

static void gpmc_cs_disable_mem(int cs)
{
	u32 l;

	l = gpmc_cs_read_reg(cs, GPMC_CS_CONFIG7);
	l &= ~GPMC_CONFIG7_CSVALID;
	gpmc_cs_write_reg(cs, GPMC_CS_CONFIG7, l);
}

static void gpmc_cs_get_memconf(int cs, u32 *base, u32 *size)
{
	u32 l;
	u32 mask;

	l = gpmc_cs_read_reg(cs, GPMC_CS_CONFIG7);
	*base = (l & 0x3f) << GPMC_CHUNK_SHIFT;
	mask = (l >> 8) & 0x0f;
	*size = (1 << GPMC_SECTION_SHIFT) - (mask << GPMC_CHUNK_SHIFT);
}

static int gpmc_cs_mem_enabled(int cs)
{
	u32 l;

	l = gpmc_cs_read_reg(cs, GPMC_CS_CONFIG7);
	return l & GPMC_CONFIG7_CSVALID;
}

static void gpmc_cs_set_reserved(int cs, int reserved)
{
	gpmc_cs_map &= ~(1 << cs);
	gpmc_cs_map |= (reserved ? 1 : 0) << cs;
}

static bool gpmc_cs_reserved(int cs)
{
	return gpmc_cs_map & (1 << cs);
}

static unsigned long gpmc_mem_align(unsigned long size)
{
	int order;

	size = (size - 1) >> (GPMC_CHUNK_SHIFT - 1);
	order = GPMC_CHUNK_SHIFT - 1;
	do {
		size >>= 1;
		order++;
	} while (size);
	size = 1 << order;
	return size;
}

static int gpmc_cs_insert_mem(int cs, unsigned long base, unsigned long size)
{
	struct resource	*res = &gpmc_cs_mem[cs];
	int r;

	size = gpmc_mem_align(size);
	spin_lock(&gpmc_mem_lock);
	res->start = base;
	res->end = base + size - 1;
	r = request_resource(&gpmc_mem_root, res);
	spin_unlock(&gpmc_mem_lock);

	return r;
}

static int gpmc_cs_delete_mem(int cs)
{
	struct resource	*res = &gpmc_cs_mem[cs];
	int r;

	spin_lock(&gpmc_mem_lock);
	r = release_resource(res);
	res->start = 0;
	res->end = 0;
	spin_unlock(&gpmc_mem_lock);

	return r;
}

/**
 * gpmc_cs_remap - remaps a chip-select physical base address
 * @cs:		chip-select to remap
 * @base:	physical base address to re-map chip-select to
 *
 * Re-maps a chip-select to a new physical base address specified by
 * "base". Returns 0 on success and appropriate negative error code
 * on failure.
 */
static int gpmc_cs_remap(int cs, u32 base)
{
	int ret;
	u32 old_base, size;

	if (cs > gpmc_cs_num) {
		pr_err("%s: requested chip-select is disabled\n", __func__);
		return -ENODEV;
	}

	/*
	 * Make sure we ignore any device offsets from the GPMC partition
	 * allocated for the chip select and that the new base confirms
	 * to the GPMC 16MB minimum granularity.
	 */ 
	base &= ~(SZ_16M - 1);

	gpmc_cs_get_memconf(cs, &old_base, &size);
	if (base == old_base)
		return 0;
	gpmc_cs_disable_mem(cs);
	ret = gpmc_cs_delete_mem(cs);
	if (ret < 0)
		return ret;
	ret = gpmc_cs_insert_mem(cs, base, size);
	if (ret < 0)
		return ret;
	ret = gpmc_cs_enable_mem(cs, base, size);
	if (ret < 0)
		return ret;

	return 0;
}

int gpmc_cs_request(int cs, unsigned long size, unsigned long *base)
{
	struct resource *res = &gpmc_cs_mem[cs];
	int r = -1;

	if (cs > gpmc_cs_num) {
		pr_err("%s: requested chip-select is disabled\n", __func__);
		return -ENODEV;
	}
	size = gpmc_mem_align(size);
	if (size > (1 << GPMC_SECTION_SHIFT))
		return -ENOMEM;

	spin_lock(&gpmc_mem_lock);
	if (gpmc_cs_reserved(cs)) {
		r = -EBUSY;
		goto out;
	}
	if (gpmc_cs_mem_enabled(cs))
		r = adjust_resource(res, res->start & ~(size - 1), size);
	if (r < 0)
		r = allocate_resource(&gpmc_mem_root, res, size, 0, ~0,
				      size, NULL, NULL);
	if (r < 0)
		goto out;

	r = gpmc_cs_enable_mem(cs, res->start, resource_size(res));
	if (r < 0) {
		release_resource(res);
		goto out;
	}

	*base = res->start;
	gpmc_cs_set_reserved(cs, 1);
out:
	spin_unlock(&gpmc_mem_lock);
	return r;
}
EXPORT_SYMBOL(gpmc_cs_request);

void gpmc_cs_free(int cs)
{
	struct resource	*res = &gpmc_cs_mem[cs];

	spin_lock(&gpmc_mem_lock);
	if (cs >= gpmc_cs_num || cs < 0 || !gpmc_cs_reserved(cs)) {
		printk(KERN_ERR "Trying to free non-reserved GPMC CS%d\n", cs);
		BUG();
		spin_unlock(&gpmc_mem_lock);
		return;
	}
	gpmc_cs_disable_mem(cs);
	if (res->flags)
		release_resource(res);
	gpmc_cs_set_reserved(cs, 0);
	spin_unlock(&gpmc_mem_lock);
}
EXPORT_SYMBOL(gpmc_cs_free);

/**
 * gpmc_configure - write request to configure gpmc
 * @cmd: command type
 * @wval: value to write
 * @return status of the operation
 */
int gpmc_configure(int cmd, int wval)
{
	u32 regval;

	switch (cmd) {
	case GPMC_ENABLE_IRQ:
		gpmc_write_reg(GPMC_IRQENABLE, wval);
		break;

	case GPMC_SET_IRQ_STATUS:
		gpmc_write_reg(GPMC_IRQSTATUS, wval);
		break;

	case GPMC_CONFIG_WP:
		regval = gpmc_read_reg(GPMC_CONFIG);
		if (wval)
			regval &= ~GPMC_CONFIG_WRITEPROTECT; /* WP is ON */
		else
			regval |= GPMC_CONFIG_WRITEPROTECT;  /* WP is OFF */
		gpmc_write_reg(GPMC_CONFIG, regval);
		break;

	default:
		pr_err("%s: command not supported\n", __func__);
		return -EINVAL;
	}

	return 0;
}
EXPORT_SYMBOL(gpmc_configure);

void gpmc_update_nand_reg(struct gpmc_nand_regs *reg, int cs)
{
	int i;

	reg->gpmc_status = gpmc_base + GPMC_STATUS;
	reg->gpmc_nand_command = gpmc_base + GPMC_CS0_OFFSET +
				GPMC_CS_NAND_COMMAND + GPMC_CS_SIZE * cs;
	reg->gpmc_nand_address = gpmc_base + GPMC_CS0_OFFSET +
				GPMC_CS_NAND_ADDRESS + GPMC_CS_SIZE * cs;
	reg->gpmc_nand_data = gpmc_base + GPMC_CS0_OFFSET +
				GPMC_CS_NAND_DATA + GPMC_CS_SIZE * cs;
	reg->gpmc_prefetch_config1 = gpmc_base + GPMC_PREFETCH_CONFIG1;
	reg->gpmc_prefetch_config2 = gpmc_base + GPMC_PREFETCH_CONFIG2;
	reg->gpmc_prefetch_control = gpmc_base + GPMC_PREFETCH_CONTROL;
	reg->gpmc_prefetch_status = gpmc_base + GPMC_PREFETCH_STATUS;
	reg->gpmc_ecc_config = gpmc_base + GPMC_ECC_CONFIG;
	reg->gpmc_ecc_control = gpmc_base + GPMC_ECC_CONTROL;
	reg->gpmc_ecc_size_config = gpmc_base + GPMC_ECC_SIZE_CONFIG;
	reg->gpmc_ecc1_result = gpmc_base + GPMC_ECC1_RESULT;

	for (i = 0; i < GPMC_BCH_NUM_REMAINDER; i++) {
		reg->gpmc_bch_result0[i] = gpmc_base + GPMC_ECC_BCH_RESULT_0 +
					   GPMC_BCH_SIZE * i;
		reg->gpmc_bch_result1[i] = gpmc_base + GPMC_ECC_BCH_RESULT_1 +
					   GPMC_BCH_SIZE * i;
		reg->gpmc_bch_result2[i] = gpmc_base + GPMC_ECC_BCH_RESULT_2 +
					   GPMC_BCH_SIZE * i;
		reg->gpmc_bch_result3[i] = gpmc_base + GPMC_ECC_BCH_RESULT_3 +
					   GPMC_BCH_SIZE * i;
		reg->gpmc_bch_result4[i] = gpmc_base + GPMC_ECC_BCH_RESULT_4 +
					   i * GPMC_BCH_SIZE;
		reg->gpmc_bch_result5[i] = gpmc_base + GPMC_ECC_BCH_RESULT_5 +
					   i * GPMC_BCH_SIZE;
		reg->gpmc_bch_result6[i] = gpmc_base + GPMC_ECC_BCH_RESULT_6 +
					   i * GPMC_BCH_SIZE;
	}
}

int gpmc_get_client_irq(unsigned irq_config)
{
	int i;

	if (hweight32(irq_config) > 1)
		return 0;

	for (i = 0; i < GPMC_NR_IRQ; i++)
		if (gpmc_client_irq[i].bitmask & irq_config)
			return gpmc_client_irq[i].irq;

	return 0;
}

static int gpmc_irq_endis(unsigned irq, bool endis)
{
	int i;
	u32 regval;

	for (i = 0; i < GPMC_NR_IRQ; i++)
		if (irq == gpmc_client_irq[i].irq) {
			regval = gpmc_read_reg(GPMC_IRQENABLE);
			if (endis)
				regval |= gpmc_client_irq[i].bitmask;
			else
				regval &= ~gpmc_client_irq[i].bitmask;
			gpmc_write_reg(GPMC_IRQENABLE, regval);
			break;
		}

	return 0;
}

static void gpmc_irq_disable(struct irq_data *p)
{
	gpmc_irq_endis(p->irq, false);
}

static void gpmc_irq_enable(struct irq_data *p)
{
	gpmc_irq_endis(p->irq, true);
}

static void gpmc_irq_noop(struct irq_data *data) { }

static unsigned int gpmc_irq_noop_ret(struct irq_data *data) { return 0; }

static int gpmc_setup_irq(void)
{
	int i;
	u32 regval;

	if (!gpmc_irq)
		return -EINVAL;

	gpmc_irq_start = irq_alloc_descs(-1, 0, GPMC_NR_IRQ, 0);
	if (gpmc_irq_start < 0) {
		pr_err("irq_alloc_descs failed\n");
		return gpmc_irq_start;
	}

	gpmc_irq_chip.name = "gpmc";
	gpmc_irq_chip.irq_startup = gpmc_irq_noop_ret;
	gpmc_irq_chip.irq_enable = gpmc_irq_enable;
	gpmc_irq_chip.irq_disable = gpmc_irq_disable;
	gpmc_irq_chip.irq_shutdown = gpmc_irq_noop;
	gpmc_irq_chip.irq_ack = gpmc_irq_noop;
	gpmc_irq_chip.irq_mask = gpmc_irq_noop;
	gpmc_irq_chip.irq_unmask = gpmc_irq_noop;

	gpmc_client_irq[0].bitmask = GPMC_IRQ_FIFOEVENTENABLE;
	gpmc_client_irq[1].bitmask = GPMC_IRQ_COUNT_EVENT;

	for (i = 0; i < GPMC_NR_IRQ; i++) {
		gpmc_client_irq[i].irq = gpmc_irq_start + i;
		irq_set_chip_and_handler(gpmc_client_irq[i].irq,
					&gpmc_irq_chip, handle_simple_irq);
		set_irq_flags(gpmc_client_irq[i].irq,
				IRQF_VALID | IRQF_NOAUTOEN);
	}

	/* Disable interrupts */
	gpmc_write_reg(GPMC_IRQENABLE, 0);

	/* clear interrupts */
	regval = gpmc_read_reg(GPMC_IRQSTATUS);
	gpmc_write_reg(GPMC_IRQSTATUS, regval);

	return request_irq(gpmc_irq, gpmc_handle_irq, 0, "gpmc", NULL);
}

static int gpmc_free_irq(void)
{
	int i;

	if (gpmc_irq)
		free_irq(gpmc_irq, NULL);

	for (i = 0; i < GPMC_NR_IRQ; i++) {
		irq_set_handler(gpmc_client_irq[i].irq, NULL);
		irq_set_chip(gpmc_client_irq[i].irq, &no_irq_chip);
		irq_modify_status(gpmc_client_irq[i].irq, 0, 0);
	}

	irq_free_descs(gpmc_irq_start, GPMC_NR_IRQ);

	return 0;
}

static void gpmc_mem_exit(void)
{
	int cs;

	for (cs = 0; cs < gpmc_cs_num; cs++) {
		if (!gpmc_cs_mem_enabled(cs))
			continue;
		gpmc_cs_delete_mem(cs);
	}

}

static void gpmc_mem_init(void)
{
	int cs;

	/*
	 * The first 1MB of GPMC address space is typically mapped to
	 * the internal ROM. Never allocate the first page, to
	 * facilitate bug detection; even if we didn't boot from ROM.
	 */
	gpmc_mem_root.start = SZ_1M;
	gpmc_mem_root.end = GPMC_MEM_END;

	/* Reserve all regions that has been set up by bootloader */
	for (cs = 0; cs < gpmc_cs_num; cs++) {
		u32 base, size;

		if (!gpmc_cs_mem_enabled(cs))
			continue;
		gpmc_cs_get_memconf(cs, &base, &size);
		if (gpmc_cs_insert_mem(cs, base, size)) {
			pr_warn("%s: disabling cs %d mapped at 0x%x-0x%x\n",
				__func__, cs, base, base + size);
			gpmc_cs_disable_mem(cs);
		}
	}
}

static u32 gpmc_round_ps_to_sync_clk(u32 time_ps, u32 sync_clk)
{
	u32 temp;
	int div;

	div = gpmc_calc_divider(sync_clk);
	temp = gpmc_ps_to_ticks(time_ps);
	temp = (temp + div - 1) / div;
	return gpmc_ticks_to_ps(temp * div);
}

/* XXX: can the cycles be avoided ? */
static int gpmc_calc_sync_read_timings(struct gpmc_timings *gpmc_t,
				       struct gpmc_device_timings *dev_t,
				       bool mux)
{
	u32 temp;

	/* adv_rd_off */
	temp = dev_t->t_avdp_r;
	/* XXX: mux check required ? */
	if (mux) {
		/* XXX: t_avdp not to be required for sync, only added for tusb
		 * this indirectly necessitates requirement of t_avdp_r and
		 * t_avdp_w instead of having a single t_avdp
		 */
		temp = max_t(u32, temp,	gpmc_t->clk_activation + dev_t->t_avdh);
		temp = max_t(u32, gpmc_t->adv_on + gpmc_ticks_to_ps(1), temp);
	}
	gpmc_t->adv_rd_off = gpmc_round_ps_to_ticks(temp);

	/* oe_on */
	temp = dev_t->t_oeasu; /* XXX: remove this ? */
	if (mux) {
		temp = max_t(u32, temp,	gpmc_t->clk_activation + dev_t->t_ach);
		temp = max_t(u32, temp, gpmc_t->adv_rd_off +
				gpmc_ticks_to_ps(dev_t->cyc_aavdh_oe));
	}
	gpmc_t->oe_on = gpmc_round_ps_to_ticks(temp);

	/* access */
	/* XXX: any scope for improvement ?, by combining oe_on
	 * and clk_activation, need to check whether
	 * access = clk_activation + round to sync clk ?
	 */
	temp = max_t(u32, dev_t->t_iaa,	dev_t->cyc_iaa * gpmc_t->sync_clk);
	temp += gpmc_t->clk_activation;
	if (dev_t->cyc_oe)
		temp = max_t(u32, temp, gpmc_t->oe_on +
				gpmc_ticks_to_ps(dev_t->cyc_oe));
	gpmc_t->access = gpmc_round_ps_to_ticks(temp);

	gpmc_t->oe_off = gpmc_t->access + gpmc_ticks_to_ps(1);
	gpmc_t->cs_rd_off = gpmc_t->oe_off;

	/* rd_cycle */
	temp = max_t(u32, dev_t->t_cez_r, dev_t->t_oez);
	temp = gpmc_round_ps_to_sync_clk(temp, gpmc_t->sync_clk) +
							gpmc_t->access;
	/* XXX: barter t_ce_rdyz with t_cez_r ? */
	if (dev_t->t_ce_rdyz)
		temp = max_t(u32, temp,	gpmc_t->cs_rd_off + dev_t->t_ce_rdyz);
	gpmc_t->rd_cycle = gpmc_round_ps_to_ticks(temp);

	return 0;
}

static int gpmc_calc_sync_write_timings(struct gpmc_timings *gpmc_t,
					struct gpmc_device_timings *dev_t,
					bool mux)
{
	u32 temp;

	/* adv_wr_off */
	temp = dev_t->t_avdp_w;
	if (mux) {
		temp = max_t(u32, temp,
			gpmc_t->clk_activation + dev_t->t_avdh);
		temp = max_t(u32, gpmc_t->adv_on + gpmc_ticks_to_ps(1), temp);
	}
	gpmc_t->adv_wr_off = gpmc_round_ps_to_ticks(temp);

	/* wr_data_mux_bus */
	temp = max_t(u32, dev_t->t_weasu,
			gpmc_t->clk_activation + dev_t->t_rdyo);
	/* XXX: shouldn't mux be kept as a whole for wr_data_mux_bus ?,
	 * and in that case remember to handle we_on properly
	 */
	if (mux) {
		temp = max_t(u32, temp,
			gpmc_t->adv_wr_off + dev_t->t_aavdh);
		temp = max_t(u32, temp, gpmc_t->adv_wr_off +
				gpmc_ticks_to_ps(dev_t->cyc_aavdh_we));
	}
	gpmc_t->wr_data_mux_bus = gpmc_round_ps_to_ticks(temp);

	/* we_on */
	if (gpmc_capability & GPMC_HAS_WR_DATA_MUX_BUS)
		gpmc_t->we_on = gpmc_round_ps_to_ticks(dev_t->t_weasu);
	else
		gpmc_t->we_on = gpmc_t->wr_data_mux_bus;

	/* wr_access */
	/* XXX: gpmc_capability check reqd ? , even if not, will not harm */
	gpmc_t->wr_access = gpmc_t->access;

	/* we_off */
	temp = gpmc_t->we_on + dev_t->t_wpl;
	temp = max_t(u32, temp,
			gpmc_t->wr_access + gpmc_ticks_to_ps(1));
	temp = max_t(u32, temp,
		gpmc_t->we_on + gpmc_ticks_to_ps(dev_t->cyc_wpl));
	gpmc_t->we_off = gpmc_round_ps_to_ticks(temp);

	gpmc_t->cs_wr_off = gpmc_round_ps_to_ticks(gpmc_t->we_off +
							dev_t->t_wph);

	/* wr_cycle */
	temp = gpmc_round_ps_to_sync_clk(dev_t->t_cez_w, gpmc_t->sync_clk);
	temp += gpmc_t->wr_access;
	/* XXX: barter t_ce_rdyz with t_cez_w ? */
	if (dev_t->t_ce_rdyz)
		temp = max_t(u32, temp,
				 gpmc_t->cs_wr_off + dev_t->t_ce_rdyz);
	gpmc_t->wr_cycle = gpmc_round_ps_to_ticks(temp);

	return 0;
}

static int gpmc_calc_async_read_timings(struct gpmc_timings *gpmc_t,
					struct gpmc_device_timings *dev_t,
					bool mux)
{
	u32 temp;

	/* adv_rd_off */
	temp = dev_t->t_avdp_r;
	if (mux)
		temp = max_t(u32, gpmc_t->adv_on + gpmc_ticks_to_ps(1), temp);
	gpmc_t->adv_rd_off = gpmc_round_ps_to_ticks(temp);

	/* oe_on */
	temp = dev_t->t_oeasu;
	if (mux)
		temp = max_t(u32, temp,
			gpmc_t->adv_rd_off + dev_t->t_aavdh);
	gpmc_t->oe_on = gpmc_round_ps_to_ticks(temp);

	/* access */
	temp = max_t(u32, dev_t->t_iaa, /* XXX: remove t_iaa in async ? */
				gpmc_t->oe_on + dev_t->t_oe);
	temp = max_t(u32, temp,
				gpmc_t->cs_on + dev_t->t_ce);
	temp = max_t(u32, temp,
				gpmc_t->adv_on + dev_t->t_aa);
	gpmc_t->access = gpmc_round_ps_to_ticks(temp);

	gpmc_t->oe_off = gpmc_t->access + gpmc_ticks_to_ps(1);
	gpmc_t->cs_rd_off = gpmc_t->oe_off;

	/* rd_cycle */
	temp = max_t(u32, dev_t->t_rd_cycle,
			gpmc_t->cs_rd_off + dev_t->t_cez_r);
	temp = max_t(u32, temp, gpmc_t->oe_off + dev_t->t_oez);
	gpmc_t->rd_cycle = gpmc_round_ps_to_ticks(temp);

	return 0;
}

static int gpmc_calc_async_write_timings(struct gpmc_timings *gpmc_t,
					 struct gpmc_device_timings *dev_t,
					 bool mux)
{
	u32 temp;

	/* adv_wr_off */
	temp = dev_t->t_avdp_w;
	if (mux)
		temp = max_t(u32, gpmc_t->adv_on + gpmc_ticks_to_ps(1), temp);
	gpmc_t->adv_wr_off = gpmc_round_ps_to_ticks(temp);

	/* wr_data_mux_bus */
	temp = dev_t->t_weasu;
	if (mux) {
		temp = max_t(u32, temp,	gpmc_t->adv_wr_off + dev_t->t_aavdh);
		temp = max_t(u32, temp, gpmc_t->adv_wr_off +
				gpmc_ticks_to_ps(dev_t->cyc_aavdh_we));
	}
	gpmc_t->wr_data_mux_bus = gpmc_round_ps_to_ticks(temp);

	/* we_on */
	if (gpmc_capability & GPMC_HAS_WR_DATA_MUX_BUS)
		gpmc_t->we_on = gpmc_round_ps_to_ticks(dev_t->t_weasu);
	else
		gpmc_t->we_on = gpmc_t->wr_data_mux_bus;

	/* we_off */
	temp = gpmc_t->we_on + dev_t->t_wpl;
	gpmc_t->we_off = gpmc_round_ps_to_ticks(temp);

	gpmc_t->cs_wr_off = gpmc_round_ps_to_ticks(gpmc_t->we_off +
							dev_t->t_wph);

	/* wr_cycle */
	temp = max_t(u32, dev_t->t_wr_cycle,
				gpmc_t->cs_wr_off + dev_t->t_cez_w);
	gpmc_t->wr_cycle = gpmc_round_ps_to_ticks(temp);

	return 0;
}

static int gpmc_calc_sync_common_timings(struct gpmc_timings *gpmc_t,
			struct gpmc_device_timings *dev_t)
{
	u32 temp;

	gpmc_t->sync_clk = gpmc_calc_divider(dev_t->clk) *
						gpmc_get_fclk_period();

	gpmc_t->page_burst_access = gpmc_round_ps_to_sync_clk(
					dev_t->t_bacc,
					gpmc_t->sync_clk);

	temp = max_t(u32, dev_t->t_ces, dev_t->t_avds);
	gpmc_t->clk_activation = gpmc_round_ps_to_ticks(temp);

	if (gpmc_calc_divider(gpmc_t->sync_clk) != 1)
		return 0;

	if (dev_t->ce_xdelay)
		gpmc_t->bool_timings.cs_extra_delay = true;
	if (dev_t->avd_xdelay)
		gpmc_t->bool_timings.adv_extra_delay = true;
	if (dev_t->oe_xdelay)
		gpmc_t->bool_timings.oe_extra_delay = true;
	if (dev_t->we_xdelay)
		gpmc_t->bool_timings.we_extra_delay = true;

	return 0;
}

static int gpmc_calc_common_timings(struct gpmc_timings *gpmc_t,
				    struct gpmc_device_timings *dev_t,
				    bool sync)
{
	u32 temp;

	/* cs_on */
	gpmc_t->cs_on = gpmc_round_ps_to_ticks(dev_t->t_ceasu);

	/* adv_on */
	temp = dev_t->t_avdasu;
	if (dev_t->t_ce_avd)
		temp = max_t(u32, temp,
				gpmc_t->cs_on + dev_t->t_ce_avd);
	gpmc_t->adv_on = gpmc_round_ps_to_ticks(temp);

	if (sync)
		gpmc_calc_sync_common_timings(gpmc_t, dev_t);

	return 0;
}

/* TODO: remove this function once all peripherals are confirmed to
 * work with generic timing. Simultaneously gpmc_cs_set_timings()
 * has to be modified to handle timings in ps instead of ns
*/
static void gpmc_convert_ps_to_ns(struct gpmc_timings *t)
{
	t->cs_on /= 1000;
	t->cs_rd_off /= 1000;
	t->cs_wr_off /= 1000;
	t->adv_on /= 1000;
	t->adv_rd_off /= 1000;
	t->adv_wr_off /= 1000;
	t->we_on /= 1000;
	t->we_off /= 1000;
	t->oe_on /= 1000;
	t->oe_off /= 1000;
	t->page_burst_access /= 1000;
	t->access /= 1000;
	t->rd_cycle /= 1000;
	t->wr_cycle /= 1000;
	t->bus_turnaround /= 1000;
	t->cycle2cycle_delay /= 1000;
	t->wait_monitoring /= 1000;
	t->clk_activation /= 1000;
	t->wr_access /= 1000;
	t->wr_data_mux_bus /= 1000;
}

int gpmc_calc_timings(struct gpmc_timings *gpmc_t,
		      struct gpmc_settings *gpmc_s,
		      struct gpmc_device_timings *dev_t)
{
	bool mux = false, sync = false;

	if (gpmc_s) {
		mux = gpmc_s->mux_add_data ? true : false;
		sync = (gpmc_s->sync_read || gpmc_s->sync_write);
	}

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

	gpmc_calc_common_timings(gpmc_t, dev_t, sync);

	if (gpmc_s && gpmc_s->sync_read)
		gpmc_calc_sync_read_timings(gpmc_t, dev_t, mux);
	else
		gpmc_calc_async_read_timings(gpmc_t, dev_t, mux);

	if (gpmc_s && gpmc_s->sync_write)
		gpmc_calc_sync_write_timings(gpmc_t, dev_t, mux);
	else
		gpmc_calc_async_write_timings(gpmc_t, dev_t, mux);

	/* TODO: remove, see function definition */
	gpmc_convert_ps_to_ns(gpmc_t);

	return 0;
}

/**
 * gpmc_cs_program_settings - programs non-timing related settings
 * @cs:		GPMC chip-select to program
 * @p:		pointer to GPMC settings structure
 *
 * Programs non-timing related settings for a GPMC chip-select, such as
 * bus-width, burst configuration, etc. Function should be called once
 * for each chip-select that is being used and must be called before
 * calling gpmc_cs_set_timings() as timing parameters in the CONFIG1
 * register will be initialised to zero by this function. Returns 0 on
 * success and appropriate negative error code on failure.
 */
int gpmc_cs_program_settings(int cs, struct gpmc_settings *p)
{
	u32 config1;

	if ((!p->device_width) || (p->device_width > GPMC_DEVWIDTH_16BIT)) {
		pr_err("%s: invalid width %d!", __func__, p->device_width);
		return -EINVAL;
	}

	/* Address-data multiplexing not supported for NAND devices */
	if (p->device_nand && p->mux_add_data) {
		pr_err("%s: invalid configuration!\n", __func__);
		return -EINVAL;
	}

	if ((p->mux_add_data > GPMC_MUX_AD) ||
	    ((p->mux_add_data == GPMC_MUX_AAD) &&
	     !(gpmc_capability & GPMC_HAS_MUX_AAD))) {
		pr_err("%s: invalid multiplex configuration!\n", __func__);
		return -EINVAL;
	}

	/* Page/burst mode supports lengths of 4, 8 and 16 bytes */
	if (p->burst_read || p->burst_write) {
		switch (p->burst_len) {
		case GPMC_BURST_4:
		case GPMC_BURST_8:
		case GPMC_BURST_16:
			break;
		default:
			pr_err("%s: invalid page/burst-length (%d)\n",
			       __func__, p->burst_len);
			return -EINVAL;
		}
	}

	if ((p->wait_on_read || p->wait_on_write) &&
	    (p->wait_pin > gpmc_nr_waitpins)) {
		pr_err("%s: invalid wait-pin (%d)\n", __func__, p->wait_pin);
		return -EINVAL;
	}

	config1 = GPMC_CONFIG1_DEVICESIZE((p->device_width - 1));

	if (p->sync_read)
		config1 |= GPMC_CONFIG1_READTYPE_SYNC;
	if (p->sync_write)
		config1 |= GPMC_CONFIG1_WRITETYPE_SYNC;
	if (p->wait_on_read)
		config1 |= GPMC_CONFIG1_WAIT_READ_MON;
	if (p->wait_on_write)
		config1 |= GPMC_CONFIG1_WAIT_WRITE_MON;
	if (p->wait_on_read || p->wait_on_write)
		config1 |= GPMC_CONFIG1_WAIT_PIN_SEL(p->wait_pin);
	if (p->device_nand)
		config1	|= GPMC_CONFIG1_DEVICETYPE(GPMC_DEVICETYPE_NAND);
	if (p->mux_add_data)
		config1	|= GPMC_CONFIG1_MUXTYPE(p->mux_add_data);
	if (p->burst_read)
		config1 |= GPMC_CONFIG1_READMULTIPLE_SUPP;
	if (p->burst_write)
		config1 |= GPMC_CONFIG1_WRITEMULTIPLE_SUPP;
	if (p->burst_read || p->burst_write) {
		config1 |= GPMC_CONFIG1_PAGE_LEN(p->burst_len >> 3);
		config1 |= p->burst_wrap ? GPMC_CONFIG1_WRAPBURST_SUPP : 0;
	}

	gpmc_cs_write_reg(cs, GPMC_CS_CONFIG1, config1);

	return 0;
}

#ifdef CONFIG_OF
static struct of_device_id gpmc_dt_ids[] = {
	{ .compatible = "ti,omap2420-gpmc" },
	{ .compatible = "ti,omap2430-gpmc" },
	{ .compatible = "ti,omap3430-gpmc" },	/* omap3430 & omap3630 */
	{ .compatible = "ti,omap4430-gpmc" },	/* omap4430 & omap4460 & omap543x */
	{ .compatible = "ti,am3352-gpmc" },	/* am335x devices */
	{ }
};
MODULE_DEVICE_TABLE(of, gpmc_dt_ids);

/**
 * gpmc_read_settings_dt - read gpmc settings from device-tree
 * @np:		pointer to device-tree node for a gpmc child device
 * @p:		pointer to gpmc settings structure
 *
 * Reads the GPMC settings for a GPMC child device from device-tree and
 * stores them in the GPMC settings structure passed. The GPMC settings
 * structure is initialised to zero by this function and so any
 * previously stored settings will be cleared.
 */
void gpmc_read_settings_dt(struct device_node *np, struct gpmc_settings *p)
{
	memset(p, 0, sizeof(struct gpmc_settings));

	p->sync_read = of_property_read_bool(np, "gpmc,sync-read");
	p->sync_write = of_property_read_bool(np, "gpmc,sync-write");
	of_property_read_u32(np, "gpmc,device-width", &p->device_width);
	of_property_read_u32(np, "gpmc,mux-add-data", &p->mux_add_data);

	if (!of_property_read_u32(np, "gpmc,burst-length", &p->burst_len)) {
		p->burst_wrap = of_property_read_bool(np, "gpmc,burst-wrap");
		p->burst_read = of_property_read_bool(np, "gpmc,burst-read");
		p->burst_write = of_property_read_bool(np, "gpmc,burst-write");
		if (!p->burst_read && !p->burst_write)
			pr_warn("%s: page/burst-length set but not used!\n",
				__func__);
	}

	if (!of_property_read_u32(np, "gpmc,wait-pin", &p->wait_pin)) {
		p->wait_on_read = of_property_read_bool(np,
							"gpmc,wait-on-read");
		p->wait_on_write = of_property_read_bool(np,
							 "gpmc,wait-on-write");
		if (!p->wait_on_read && !p->wait_on_write)
			pr_warn("%s: read/write wait monitoring not enabled!\n",
				__func__);
	}
}

static void __maybe_unused gpmc_read_timings_dt(struct device_node *np,
						struct gpmc_timings *gpmc_t)
{
	struct gpmc_bool_timings *p;

	if (!np || !gpmc_t)
		return;

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

	/* minimum clock period for syncronous mode */
	of_property_read_u32(np, "gpmc,sync-clk-ps", &gpmc_t->sync_clk);

	/* chip select timtings */
	of_property_read_u32(np, "gpmc,cs-on-ns", &gpmc_t->cs_on);
	of_property_read_u32(np, "gpmc,cs-rd-off-ns", &gpmc_t->cs_rd_off);
	of_property_read_u32(np, "gpmc,cs-wr-off-ns", &gpmc_t->cs_wr_off);

	/* ADV signal timings */
	of_property_read_u32(np, "gpmc,adv-on-ns", &gpmc_t->adv_on);
	of_property_read_u32(np, "gpmc,adv-rd-off-ns", &gpmc_t->adv_rd_off);
	of_property_read_u32(np, "gpmc,adv-wr-off-ns", &gpmc_t->adv_wr_off);

	/* WE signal timings */
	of_property_read_u32(np, "gpmc,we-on-ns", &gpmc_t->we_on);
	of_property_read_u32(np, "gpmc,we-off-ns", &gpmc_t->we_off);

	/* OE signal timings */
	of_property_read_u32(np, "gpmc,oe-on-ns", &gpmc_t->oe_on);
	of_property_read_u32(np, "gpmc,oe-off-ns", &gpmc_t->oe_off);

	/* access and cycle timings */
	of_property_read_u32(np, "gpmc,page-burst-access-ns",
			     &gpmc_t->page_burst_access);
	of_property_read_u32(np, "gpmc,access-ns", &gpmc_t->access);
	of_property_read_u32(np, "gpmc,rd-cycle-ns", &gpmc_t->rd_cycle);
	of_property_read_u32(np, "gpmc,wr-cycle-ns", &gpmc_t->wr_cycle);
	of_property_read_u32(np, "gpmc,bus-turnaround-ns",
			     &gpmc_t->bus_turnaround);
	of_property_read_u32(np, "gpmc,cycle2cycle-delay-ns",
			     &gpmc_t->cycle2cycle_delay);
	of_property_read_u32(np, "gpmc,wait-monitoring-ns",
			     &gpmc_t->wait_monitoring);
	of_property_read_u32(np, "gpmc,clk-activation-ns",
			     &gpmc_t->clk_activation);

	/* only applicable to OMAP3+ */
	of_property_read_u32(np, "gpmc,wr-access-ns", &gpmc_t->wr_access);
	of_property_read_u32(np, "gpmc,wr-data-mux-bus-ns",
			     &gpmc_t->wr_data_mux_bus);

	/* bool timing parameters */
	p = &gpmc_t->bool_timings;

	p->cycle2cyclediffcsen =
		of_property_read_bool(np, "gpmc,cycle2cycle-diffcsen");
	p->cycle2cyclesamecsen =
		of_property_read_bool(np, "gpmc,cycle2cycle-samecsen");
	p->we_extra_delay = of_property_read_bool(np, "gpmc,we-extra-delay");
	p->oe_extra_delay = of_property_read_bool(np, "gpmc,oe-extra-delay");
	p->adv_extra_delay = of_property_read_bool(np, "gpmc,adv-extra-delay");
	p->cs_extra_delay = of_property_read_bool(np, "gpmc,cs-extra-delay");
	p->time_para_granularity =
		of_property_read_bool(np, "gpmc,time-para-granularity");
}

#if IS_ENABLED(CONFIG_MTD_NAND)

static const char * const nand_xfer_types[] = {
	[NAND_OMAP_PREFETCH_POLLED]		= "prefetch-polled",
	[NAND_OMAP_POLLED]			= "polled",
	[NAND_OMAP_PREFETCH_DMA]		= "prefetch-dma",
	[NAND_OMAP_PREFETCH_IRQ]		= "prefetch-irq",
};

static int gpmc_probe_nand_child(struct platform_device *pdev,
				 struct device_node *child)
{
	u32 val;
	const char *s;
	struct gpmc_timings gpmc_t;
	struct omap_nand_platform_data *gpmc_nand_data;

	if (of_property_read_u32(child, "reg", &val) < 0) {
		dev_err(&pdev->dev, "%s has no 'reg' property\n",
			child->full_name);
		return -ENODEV;
	}

	gpmc_nand_data = devm_kzalloc(&pdev->dev, sizeof(*gpmc_nand_data),
				      GFP_KERNEL);
	if (!gpmc_nand_data)
		return -ENOMEM;

	gpmc_nand_data->cs = val;
	gpmc_nand_data->of_node = child;

	/* Detect availability of ELM module */
	gpmc_nand_data->elm_of_node = of_parse_phandle(child, "ti,elm-id", 0);
	if (gpmc_nand_data->elm_of_node == NULL)
		gpmc_nand_data->elm_of_node =
					of_parse_phandle(child, "elm_id", 0);
	if (gpmc_nand_data->elm_of_node == NULL)
		pr_warn("%s: ti,elm-id property not found\n", __func__);

	/* select ecc-scheme for NAND */
	if (of_property_read_string(child, "ti,nand-ecc-opt", &s)) {
		pr_err("%s: ti,nand-ecc-opt not found\n", __func__);
		return -ENODEV;
	}

	if (!strcmp(s, "sw"))
		gpmc_nand_data->ecc_opt = OMAP_ECC_HAM1_CODE_SW;
	else if (!strcmp(s, "ham1") ||
		 !strcmp(s, "hw") || !strcmp(s, "hw-romcode"))
		gpmc_nand_data->ecc_opt =
				OMAP_ECC_HAM1_CODE_HW;
	else if (!strcmp(s, "bch4"))
		if (gpmc_nand_data->elm_of_node)
			gpmc_nand_data->ecc_opt =
				OMAP_ECC_BCH4_CODE_HW;
		else
			gpmc_nand_data->ecc_opt =
				OMAP_ECC_BCH4_CODE_HW_DETECTION_SW;
	else if (!strcmp(s, "bch8"))
		if (gpmc_nand_data->elm_of_node)
			gpmc_nand_data->ecc_opt =
				OMAP_ECC_BCH8_CODE_HW;
		else
			gpmc_nand_data->ecc_opt =
				OMAP_ECC_BCH8_CODE_HW_DETECTION_SW;
	else if (!strcmp(s, "bch16"))
		if (gpmc_nand_data->elm_of_node)
			gpmc_nand_data->ecc_opt =
				OMAP_ECC_BCH16_CODE_HW;
		else
			pr_err("%s: BCH16 requires ELM support\n", __func__);
	else
		pr_err("%s: ti,nand-ecc-opt invalid value\n", __func__);

	/* select data transfer mode for NAND controller */
	if (!of_property_read_string(child, "ti,nand-xfer-type", &s))
		for (val = 0; val < ARRAY_SIZE(nand_xfer_types); val++)
			if (!strcasecmp(s, nand_xfer_types[val])) {
				gpmc_nand_data->xfer_type = val;
				break;
			}

	val = of_get_nand_bus_width(child);
	if (val == 16)
		gpmc_nand_data->devsize = NAND_BUSWIDTH_16;

	gpmc_read_timings_dt(child, &gpmc_t);
	gpmc_nand_init(gpmc_nand_data, &gpmc_t);

	return 0;
}
#else
static int gpmc_probe_nand_child(struct platform_device *pdev,
				 struct device_node *child)
{
	return 0;
}
#endif

#if IS_ENABLED(CONFIG_MTD_ONENAND)
static int gpmc_probe_onenand_child(struct platform_device *pdev,
				 struct device_node *child)
{
	u32 val;
	struct omap_onenand_platform_data *gpmc_onenand_data;

	if (of_property_read_u32(child, "reg", &val) < 0) {
		dev_err(&pdev->dev, "%s has no 'reg' property\n",
			child->full_name);
		return -ENODEV;
	}

	gpmc_onenand_data = devm_kzalloc(&pdev->dev, sizeof(*gpmc_onenand_data),
					 GFP_KERNEL);
	if (!gpmc_onenand_data)
		return -ENOMEM;

	gpmc_onenand_data->cs = val;
	gpmc_onenand_data->of_node = child;
	gpmc_onenand_data->dma_channel = -1;

	if (!of_property_read_u32(child, "dma-channel", &val))
		gpmc_onenand_data->dma_channel = val;

	gpmc_onenand_init(gpmc_onenand_data);

	return 0;
}
#else
static int gpmc_probe_onenand_child(struct platform_device *pdev,
				    struct device_node *child)
{
	return 0;
}
#endif

/**
 * gpmc_probe_generic_child - configures the gpmc for a child device
 * @pdev:	pointer to gpmc platform device
 * @child:	pointer to device-tree node for child device
 *
 * Allocates and configures a GPMC chip-select for a child device.
 * Returns 0 on success and appropriate negative error code on failure.
 */
static int gpmc_probe_generic_child(struct platform_device *pdev,
				struct device_node *child)
{
	struct gpmc_settings gpmc_s;
	struct gpmc_timings gpmc_t;
	struct resource res;
	unsigned long base;
	int ret, cs;

	if (of_property_read_u32(child, "reg", &cs) < 0) {
		dev_err(&pdev->dev, "%s has no 'reg' property\n",
			child->full_name);
		return -ENODEV;
	}

	if (of_address_to_resource(child, 0, &res) < 0) {
		dev_err(&pdev->dev, "%s has malformed 'reg' property\n",
			child->full_name);
		return -ENODEV;
	}

	ret = gpmc_cs_request(cs, resource_size(&res), &base);
	if (ret < 0) {
		dev_err(&pdev->dev, "cannot request GPMC CS %d\n", cs);
		return ret;
	}

	/*
	 * For some GPMC devices we still need to rely on the bootloader
	 * timings because the devices can be connected via FPGA. So far
	 * the list is smc91x on the omap2 SDP boards, and 8250 on zooms.
	 * REVISIT: Add timing support from slls644g.pdf and from the
	 * lan91c96 manual.
	 */
	if (of_device_is_compatible(child, "ns16550a") ||
	    of_device_is_compatible(child, "smsc,lan91c94") ||
	    of_device_is_compatible(child, "smsc,lan91c111")) {
		dev_warn(&pdev->dev,
			 "%s using bootloader timings on CS%d\n",
			 child->name, cs);
		goto no_timings;
	}

	/*
	 * FIXME: gpmc_cs_request() will map the CS to an arbitary
	 * location in the gpmc address space. When booting with
	 * device-tree we want the NOR flash to be mapped to the
	 * location specified in the device-tree blob. So remap the
	 * CS to this location. Once DT migration is complete should
	 * just make gpmc_cs_request() map a specific address.
	 */
	ret = gpmc_cs_remap(cs, res.start);
	if (ret < 0) {
		dev_err(&pdev->dev, "cannot remap GPMC CS %d to %pa\n",
			cs, &res.start);
		goto err;
	}

	gpmc_read_settings_dt(child, &gpmc_s);

	ret = of_property_read_u32(child, "bank-width", &gpmc_s.device_width);
	if (ret < 0)
		goto err;

	ret = gpmc_cs_program_settings(cs, &gpmc_s);
	if (ret < 0)
		goto err;

	gpmc_read_timings_dt(child, &gpmc_t);
	gpmc_cs_set_timings(cs, &gpmc_t);

no_timings:
	if (of_platform_device_create(child, NULL, &pdev->dev))
		return 0;

	dev_err(&pdev->dev, "failed to create gpmc child %s\n", child->name);
	ret = -ENODEV;

err:
	gpmc_cs_free(cs);

	return ret;
}

static int gpmc_probe_dt(struct platform_device *pdev)
{
	int ret;
	struct device_node *child;
	const struct of_device_id *of_id =
		of_match_device(gpmc_dt_ids, &pdev->dev);

	if (!of_id)
		return 0;

	ret = of_property_read_u32(pdev->dev.of_node, "gpmc,num-cs",
				   &gpmc_cs_num);
	if (ret < 0) {
		pr_err("%s: number of chip-selects not defined\n", __func__);
		return ret;
	} else if (gpmc_cs_num < 1) {
		pr_err("%s: all chip-selects are disabled\n", __func__);
		return -EINVAL;
	} else if (gpmc_cs_num > GPMC_CS_NUM) {
		pr_err("%s: number of supported chip-selects cannot be > %d\n",
					 __func__, GPMC_CS_NUM);
		return -EINVAL;
	}

	ret = of_property_read_u32(pdev->dev.of_node, "gpmc,num-waitpins",
				   &gpmc_nr_waitpins);
	if (ret < 0) {
		pr_err("%s: number of wait pins not found!\n", __func__);
		return ret;
	}

	for_each_available_child_of_node(pdev->dev.of_node, child) {

		if (!child->name)
			continue;

		if (of_node_cmp(child->name, "nand") == 0)
			ret = gpmc_probe_nand_child(pdev, child);
		else if (of_node_cmp(child->name, "onenand") == 0)
			ret = gpmc_probe_onenand_child(pdev, child);
		else if (of_node_cmp(child->name, "ethernet") == 0 ||
			 of_node_cmp(child->name, "nor") == 0 ||
			 of_node_cmp(child->name, "uart") == 0)
			ret = gpmc_probe_generic_child(pdev, child);

		if (WARN(ret < 0, "%s: probing gpmc child %s failed\n",
			 __func__, child->full_name))
			of_node_put(child);
	}

	return 0;
}
#else
static int gpmc_probe_dt(struct platform_device *pdev)
{
	return 0;
}
#endif

static int gpmc_probe(struct platform_device *pdev)
{
	int rc;
	u32 l;
	struct resource *res;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (res == NULL)
		return -ENOENT;

	phys_base = res->start;
	mem_size = resource_size(res);

	gpmc_base = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(gpmc_base))
		return PTR_ERR(gpmc_base);

	res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
	if (res == NULL)
		dev_warn(&pdev->dev, "Failed to get resource: irq\n");
	else
		gpmc_irq = res->start;

	gpmc_l3_clk = clk_get(&pdev->dev, "fck");
	if (IS_ERR(gpmc_l3_clk)) {
		dev_err(&pdev->dev, "error: clk_get\n");
		gpmc_irq = 0;
		return PTR_ERR(gpmc_l3_clk);
	}

	pm_runtime_enable(&pdev->dev);
	pm_runtime_get_sync(&pdev->dev);

	gpmc_dev = &pdev->dev;

	l = gpmc_read_reg(GPMC_REVISION);

	/*
	 * FIXME: Once device-tree migration is complete the below flags
	 * should be populated based upon the device-tree compatible
	 * string. For now just use the IP revision. OMAP3+ devices have
	 * the wr_access and wr_data_mux_bus register fields. OMAP4+
	 * devices support the addr-addr-data multiplex protocol.
	 *
	 * GPMC IP revisions:
	 * - OMAP24xx			= 2.0
	 * - OMAP3xxx			= 5.0
	 * - OMAP44xx/54xx/AM335x	= 6.0
	 */
	if (GPMC_REVISION_MAJOR(l) > 0x4)
		gpmc_capability = GPMC_HAS_WR_ACCESS | GPMC_HAS_WR_DATA_MUX_BUS;
	if (GPMC_REVISION_MAJOR(l) > 0x5)
		gpmc_capability |= GPMC_HAS_MUX_AAD;
	dev_info(gpmc_dev, "GPMC revision %d.%d\n", GPMC_REVISION_MAJOR(l),
		 GPMC_REVISION_MINOR(l));

	gpmc_mem_init();

	if (gpmc_setup_irq() < 0)
		dev_warn(gpmc_dev, "gpmc_setup_irq failed\n");

	/* Now the GPMC is initialised, unreserve the chip-selects */
	gpmc_cs_map = 0;

	if (!pdev->dev.of_node) {
		gpmc_cs_num	 = GPMC_CS_NUM;
		gpmc_nr_waitpins = GPMC_NR_WAITPINS;
	}

	rc = gpmc_probe_dt(pdev);
	if (rc < 0) {
		pm_runtime_put_sync(&pdev->dev);
		clk_put(gpmc_l3_clk);
		dev_err(gpmc_dev, "failed to probe DT parameters\n");
		return rc;
	}

	return 0;
}

static int gpmc_remove(struct platform_device *pdev)
{
	gpmc_free_irq();
	gpmc_mem_exit();
	pm_runtime_put_sync(&pdev->dev);
	pm_runtime_disable(&pdev->dev);
	gpmc_dev = NULL;
	return 0;
}

#ifdef CONFIG_PM_SLEEP
static int gpmc_suspend(struct device *dev)
{
	omap3_gpmc_save_context();
	pm_runtime_put_sync(dev);
	return 0;
}

static int gpmc_resume(struct device *dev)
{
	pm_runtime_get_sync(dev);
	omap3_gpmc_restore_context();
	return 0;
}
#endif

static SIMPLE_DEV_PM_OPS(gpmc_pm_ops, gpmc_suspend, gpmc_resume);

static struct platform_driver gpmc_driver = {
	.probe		= gpmc_probe,
	.remove		= gpmc_remove,
	.driver		= {
		.name	= DEVICE_NAME,
		.owner	= THIS_MODULE,
		.of_match_table = of_match_ptr(gpmc_dt_ids),
		.pm	= &gpmc_pm_ops,
	},
};

static __init int gpmc_init(void)
{
	return platform_driver_register(&gpmc_driver);
}

static __exit void gpmc_exit(void)
{
	platform_driver_unregister(&gpmc_driver);

}

omap_postcore_initcall(gpmc_init);
module_exit(gpmc_exit);

static int __init omap_gpmc_init(void)
{
	struct omap_hwmod *oh;
	struct platform_device *pdev;
	char *oh_name = "gpmc";

	/*
	 * if the board boots up with a populated DT, do not
	 * manually add the device from this initcall
	 */
	if (of_have_populated_dt())
		return -ENODEV;

	oh = omap_hwmod_lookup(oh_name);
	if (!oh) {
		pr_err("Could not look up %s\n", oh_name);
		return -ENODEV;
	}

	pdev = omap_device_build(DEVICE_NAME, -1, oh, NULL, 0);
	WARN(IS_ERR(pdev), "could not build omap_device for %s\n", oh_name);

	return PTR_RET(pdev);
}
omap_postcore_initcall(omap_gpmc_init);

static irqreturn_t gpmc_handle_irq(int irq, void *dev)
{
	int i;
	u32 regval;

	regval = gpmc_read_reg(GPMC_IRQSTATUS);

	if (!regval)
		return IRQ_NONE;

	for (i = 0; i < GPMC_NR_IRQ; i++)
		if (regval & gpmc_client_irq[i].bitmask)
			generic_handle_irq(gpmc_client_irq[i].irq);

	gpmc_write_reg(GPMC_IRQSTATUS, regval);

	return IRQ_HANDLED;
}

static struct omap3_gpmc_regs gpmc_context;

void omap3_gpmc_save_context(void)
{
	int i;

	gpmc_context.sysconfig = gpmc_read_reg(GPMC_SYSCONFIG);
	gpmc_context.irqenable = gpmc_read_reg(GPMC_IRQENABLE);
	gpmc_context.timeout_ctrl = gpmc_read_reg(GPMC_TIMEOUT_CONTROL);
	gpmc_context.config = gpmc_read_reg(GPMC_CONFIG);
	gpmc_context.prefetch_config1 = gpmc_read_reg(GPMC_PREFETCH_CONFIG1);
	gpmc_context.prefetch_config2 = gpmc_read_reg(GPMC_PREFETCH_CONFIG2);
	gpmc_context.prefetch_control = gpmc_read_reg(GPMC_PREFETCH_CONTROL);
	for (i = 0; i < gpmc_cs_num; i++) {
		gpmc_context.cs_context[i].is_valid = gpmc_cs_mem_enabled(i);
		if (gpmc_context.cs_context[i].is_valid) {
			gpmc_context.cs_context[i].config1 =
				gpmc_cs_read_reg(i, GPMC_CS_CONFIG1);
			gpmc_context.cs_context[i].config2 =
				gpmc_cs_read_reg(i, GPMC_CS_CONFIG2);
			gpmc_context.cs_context[i].config3 =
				gpmc_cs_read_reg(i, GPMC_CS_CONFIG3);
			gpmc_context.cs_context[i].config4 =
				gpmc_cs_read_reg(i, GPMC_CS_CONFIG4);
			gpmc_context.cs_context[i].config5 =
				gpmc_cs_read_reg(i, GPMC_CS_CONFIG5);
			gpmc_context.cs_context[i].config6 =
				gpmc_cs_read_reg(i, GPMC_CS_CONFIG6);
			gpmc_context.cs_context[i].config7 =
				gpmc_cs_read_reg(i, GPMC_CS_CONFIG7);
		}
	}
}

void omap3_gpmc_restore_context(void)
{
	int i;

	gpmc_write_reg(GPMC_SYSCONFIG, gpmc_context.sysconfig);
	gpmc_write_reg(GPMC_IRQENABLE, gpmc_context.irqenable);
	gpmc_write_reg(GPMC_TIMEOUT_CONTROL, gpmc_context.timeout_ctrl);
	gpmc_write_reg(GPMC_CONFIG, gpmc_context.config);
	gpmc_write_reg(GPMC_PREFETCH_CONFIG1, gpmc_context.prefetch_config1);
	gpmc_write_reg(GPMC_PREFETCH_CONFIG2, gpmc_context.prefetch_config2);
	gpmc_write_reg(GPMC_PREFETCH_CONTROL, gpmc_context.prefetch_control);
	for (i = 0; i < gpmc_cs_num; i++) {
		if (gpmc_context.cs_context[i].is_valid) {
			gpmc_cs_write_reg(i, GPMC_CS_CONFIG1,
				gpmc_context.cs_context[i].config1);
			gpmc_cs_write_reg(i, GPMC_CS_CONFIG2,
				gpmc_context.cs_context[i].config2);
			gpmc_cs_write_reg(i, GPMC_CS_CONFIG3,
				gpmc_context.cs_context[i].config3);
			gpmc_cs_write_reg(i, GPMC_CS_CONFIG4,
				gpmc_context.cs_context[i].config4);
			gpmc_cs_write_reg(i, GPMC_CS_CONFIG5,
				gpmc_context.cs_context[i].config5);
			gpmc_cs_write_reg(i, GPMC_CS_CONFIG6,
				gpmc_context.cs_context[i].config6);
			gpmc_cs_write_reg(i, GPMC_CS_CONFIG7,
				gpmc_context.cs_context[i].config7);
		}
	}
}