aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/mtd/nand/fsmc_nand.c
blob: 0d45ef3883e821ba63aa29d2e189948a129cfc30 (plain) (blame)
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
/*
 * drivers/mtd/nand/fsmc_nand.c
 *
 * ST Microelectronics
 * Flexible Static Memory Controller (FSMC)
 * Driver for NAND portions
 *
 * Copyright © 2010 ST Microelectronics
 * Vipin Kumar <vipin.kumar@st.com>
 * Ashish Priyadarshi
 *
 * Based on drivers/mtd/nand/nomadik_nand.c
 *
 * This file is licensed under the terms of the GNU General Public
 * License version 2. This program is licensed "as is" without any
 * warranty of any kind, whether express or implied.
 */

#include <linux/clk.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/resource.h>
#include <linux/sched.h>
#include <linux/types.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/nand.h>
#include <linux/mtd/nand_ecc.h>
#include <linux/platform_device.h>
#include <linux/mtd/partitions.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/mtd/fsmc.h>
#include <linux/amba/bus.h>
#include <mtd/mtd-abi.h>

static struct nand_ecclayout fsmc_ecc1_layout = {
	.eccbytes = 24,
	.eccpos = {2, 3, 4, 18, 19, 20, 34, 35, 36, 50, 51, 52,
		66, 67, 68, 82, 83, 84, 98, 99, 100, 114, 115, 116},
	.oobfree = {
		{.offset = 8, .length = 8},
		{.offset = 24, .length = 8},
		{.offset = 40, .length = 8},
		{.offset = 56, .length = 8},
		{.offset = 72, .length = 8},
		{.offset = 88, .length = 8},
		{.offset = 104, .length = 8},
		{.offset = 120, .length = 8}
	}
};

static struct nand_ecclayout fsmc_ecc4_lp_layout = {
	.eccbytes = 104,
	.eccpos = {  2,   3,   4,   5,   6,   7,   8,
		9,  10,  11,  12,  13,  14,
		18,  19,  20,  21,  22,  23,  24,
		25,  26,  27,  28,  29,  30,
		34,  35,  36,  37,  38,  39,  40,
		41,  42,  43,  44,  45,  46,
		50,  51,  52,  53,  54,  55,  56,
		57,  58,  59,  60,  61,  62,
		66,  67,  68,  69,  70,  71,  72,
		73,  74,  75,  76,  77,  78,
		82,  83,  84,  85,  86,  87,  88,
		89,  90,  91,  92,  93,  94,
		98,  99, 100, 101, 102, 103, 104,
		105, 106, 107, 108, 109, 110,
		114, 115, 116, 117, 118, 119, 120,
		121, 122, 123, 124, 125, 126
	},
	.oobfree = {
		{.offset = 15, .length = 3},
		{.offset = 31, .length = 3},
		{.offset = 47, .length = 3},
		{.offset = 63, .length = 3},
		{.offset = 79, .length = 3},
		{.offset = 95, .length = 3},
		{.offset = 111, .length = 3},
		{.offset = 127, .length = 1}
	}
};

/*
 * ECC placement definitions in oobfree type format.
 * There are 13 bytes of ecc for every 512 byte block and it has to be read
 * consecutively and immediately after the 512 byte data block for hardware to
 * generate the error bit offsets in 512 byte data.
 * Managing the ecc bytes in the following way makes it easier for software to
 * read ecc bytes consecutive to data bytes. This way is similar to
 * oobfree structure maintained already in generic nand driver
 */
static struct fsmc_eccplace fsmc_ecc4_lp_place = {
	.eccplace = {
		{.offset = 2, .length = 13},
		{.offset = 18, .length = 13},
		{.offset = 34, .length = 13},
		{.offset = 50, .length = 13},
		{.offset = 66, .length = 13},
		{.offset = 82, .length = 13},
		{.offset = 98, .length = 13},
		{.offset = 114, .length = 13}
	}
};

static struct nand_ecclayout fsmc_ecc4_sp_layout = {
	.eccbytes = 13,
	.eccpos = { 0,  1,  2,  3,  6,  7, 8,
		9, 10, 11, 12, 13, 14
	},
	.oobfree = {
		{.offset = 15, .length = 1},
	}
};

static struct fsmc_eccplace fsmc_ecc4_sp_place = {
	.eccplace = {
		{.offset = 0, .length = 4},
		{.offset = 6, .length = 9}
	}
};


#ifdef CONFIG_MTD_PARTITIONS
/*
 * Default partition tables to be used if the partition information not
 * provided through platform data.
 *
 * Default partition layout for small page(= 512 bytes) devices
 * Size for "Root file system" is updated in driver based on actual device size
 */
static struct mtd_partition partition_info_16KB_blk[] = {
	{
		.name = "X-loader",
		.offset = 0,
		.size = 4*0x4000,
	},
	{
		.name = "U-Boot",
		.offset = 0x10000,
		.size = 20*0x4000,
	},
	{
		.name = "Kernel",
		.offset = 0x60000,
		.size = 256*0x4000,
	},
	{
		.name = "Root File System",
		.offset = 0x460000,
		.size = 0,
	},
};

/*
 * Default partition layout for large page(> 512 bytes) devices
 * Size for "Root file system" is updated in driver based on actual device size
 */
static struct mtd_partition partition_info_128KB_blk[] = {
	{
		.name = "X-loader",
		.offset = 0,
		.size = 4*0x20000,
	},
	{
		.name = "U-Boot",
		.offset = 0x80000,
		.size = 12*0x20000,
	},
	{
		.name = "Kernel",
		.offset = 0x200000,
		.size = 48*0x20000,
	},
	{
		.name = "Root File System",
		.offset = 0x800000,
		.size = 0,
	},
};

#ifdef CONFIG_MTD_CMDLINE_PARTS
const char *part_probes[] = { "cmdlinepart", NULL };
#endif
#endif

/**
 * struct fsmc_nand_data - structure for FSMC NAND device state
 *
 * @pid:		Part ID on the AMBA PrimeCell format
 * @mtd:		MTD info for a NAND flash.
 * @nand:		Chip related info for a NAND flash.
 * @partitions:		Partition info for a NAND Flash.
 * @nr_partitions:	Total number of partition of a NAND flash.
 *
 * @ecc_place:		ECC placing locations in oobfree type format.
 * @bank:		Bank number for probed device.
 * @clk:		Clock structure for FSMC.
 *
 * @data_va:		NAND port for Data.
 * @cmd_va:		NAND port for Command.
 * @addr_va:		NAND port for Address.
 * @regs_va:		FSMC regs base address.
 */
struct fsmc_nand_data {
	u32			pid;
	struct mtd_info		mtd;
	struct nand_chip	nand;
	struct mtd_partition	*partitions;
	unsigned int		nr_partitions;

	struct fsmc_eccplace	*ecc_place;
	unsigned int		bank;
	struct clk		*clk;

	struct resource		*resregs;
	struct resource		*rescmd;
	struct resource		*resaddr;
	struct resource		*resdata;

	void __iomem		*data_va;
	void __iomem		*cmd_va;
	void __iomem		*addr_va;
	void __iomem		*regs_va;

	void			(*select_chip)(uint32_t bank, uint32_t busw);
};

/* Assert CS signal based on chipnr */
static void fsmc_select_chip(struct mtd_info *mtd, int chipnr)
{
	struct nand_chip *chip = mtd->priv;
	struct fsmc_nand_data *host;

	host = container_of(mtd, struct fsmc_nand_data, mtd);

	switch (chipnr) {
	case -1:
		chip->cmd_ctrl(mtd, NAND_CMD_NONE, 0 | NAND_CTRL_CHANGE);
		break;
	case 0:
	case 1:
	case 2:
	case 3:
		if (host->select_chip)
			host->select_chip(chipnr,
					chip->options & NAND_BUSWIDTH_16);
		break;

	default:
		BUG();
	}
}

/*
 * fsmc_cmd_ctrl - For facilitaing Hardware access
 * This routine allows hardware specific access to control-lines(ALE,CLE)
 */
static void fsmc_cmd_ctrl(struct mtd_info *mtd, int cmd, unsigned int ctrl)
{
	struct nand_chip *this = mtd->priv;
	struct fsmc_nand_data *host = container_of(mtd,
					struct fsmc_nand_data, mtd);
	struct fsmc_regs *regs = host->regs_va;
	unsigned int bank = host->bank;

	if (ctrl & NAND_CTRL_CHANGE) {
		if (ctrl & NAND_CLE) {
			this->IO_ADDR_R = (void __iomem *)host->cmd_va;
			this->IO_ADDR_W = (void __iomem *)host->cmd_va;
		} else if (ctrl & NAND_ALE) {
			this->IO_ADDR_R = (void __iomem *)host->addr_va;
			this->IO_ADDR_W = (void __iomem *)host->addr_va;
		} else {
			this->IO_ADDR_R = (void __iomem *)host->data_va;
			this->IO_ADDR_W = (void __iomem *)host->data_va;
		}

		if (ctrl & NAND_NCE) {
			writel(readl(&regs->bank_regs[bank].pc) | FSMC_ENABLE,
					&regs->bank_regs[bank].pc);
		} else {
			writel(readl(&regs->bank_regs[bank].pc) & ~FSMC_ENABLE,
				       &regs->bank_regs[bank].pc);
		}
	}

	mb();

	if (cmd != NAND_CMD_NONE)
		writeb(cmd, this->IO_ADDR_W);
}

/*
 * fsmc_nand_setup - FSMC (Flexible Static Memory Controller) init routine
 *
 * This routine initializes timing parameters related to NAND memory access in
 * FSMC registers
 */
static void __init fsmc_nand_setup(struct fsmc_regs *regs, uint32_t bank,
				   uint32_t busw)
{
	uint32_t value = FSMC_DEVTYPE_NAND | FSMC_ENABLE | FSMC_WAITON;

	if (busw)
		writel(value | FSMC_DEVWID_16, &regs->bank_regs[bank].pc);
	else
		writel(value | FSMC_DEVWID_8, &regs->bank_regs[bank].pc);

	writel(readl(&regs->bank_regs[bank].pc) | FSMC_TCLR_1 | FSMC_TAR_1,
	       &regs->bank_regs[bank].pc);
	writel(FSMC_THIZ_1 | FSMC_THOLD_4 | FSMC_TWAIT_6 | FSMC_TSET_0,
	       &regs->bank_regs[bank].comm);
	writel(FSMC_THIZ_1 | FSMC_THOLD_4 | FSMC_TWAIT_6 | FSMC_TSET_0,
	       &regs->bank_regs[bank].attrib);
}

/*
 * fsmc_enable_hwecc - Enables Hardware ECC through FSMC registers
 */
static void fsmc_enable_hwecc(struct mtd_info *mtd, int mode)
{
	struct fsmc_nand_data *host = container_of(mtd,
					struct fsmc_nand_data, mtd);
	struct fsmc_regs *regs = host->regs_va;
	uint32_t bank = host->bank;

	writel(readl(&regs->bank_regs[bank].pc) & ~FSMC_ECCPLEN_256,
		       &regs->bank_regs[bank].pc);
	writel(readl(&regs->bank_regs[bank].pc) & ~FSMC_ECCEN,
			&regs->bank_regs[bank].pc);
	writel(readl(&regs->bank_regs[bank].pc) | FSMC_ECCEN,
			&regs->bank_regs[bank].pc);
}

/*
 * fsmc_read_hwecc_ecc4 - Hardware ECC calculator for ecc4 option supported by
 * FSMC. ECC is 13 bytes for 512 bytes of data (supports error correction up to
 * max of 8-bits)
 */
static int fsmc_read_hwecc_ecc4(struct mtd_info *mtd, const uint8_t *data,
				uint8_t *ecc)
{
	struct fsmc_nand_data *host = container_of(mtd,
					struct fsmc_nand_data, mtd);
	struct fsmc_regs *regs = host->regs_va;
	uint32_t bank = host->bank;
	uint32_t ecc_tmp;
	unsigned long deadline = jiffies + FSMC_BUSY_WAIT_TIMEOUT;

	do {
		if (readl(&regs->bank_regs[bank].sts) & FSMC_CODE_RDY)
			break;
		else
			cond_resched();
	} while (!time_after_eq(jiffies, deadline));

	ecc_tmp = readl(&regs->bank_regs[bank].ecc1);
	ecc[0] = (uint8_t) (ecc_tmp >> 0);
	ecc[1] = (uint8_t) (ecc_tmp >> 8);
	ecc[2] = (uint8_t) (ecc_tmp >> 16);
	ecc[3] = (uint8_t) (ecc_tmp >> 24);

	ecc_tmp = readl(&regs->bank_regs[bank].ecc2);
	ecc[4] = (uint8_t) (ecc_tmp >> 0);
	ecc[5] = (uint8_t) (ecc_tmp >> 8);
	ecc[6] = (uint8_t) (ecc_tmp >> 16);
	ecc[7] = (uint8_t) (ecc_tmp >> 24);

	ecc_tmp = readl(&regs->bank_regs[bank].ecc3);
	ecc[8] = (uint8_t) (ecc_tmp >> 0);
	ecc[9] = (uint8_t) (ecc_tmp >> 8);
	ecc[10] = (uint8_t) (ecc_tmp >> 16);
	ecc[11] = (uint8_t) (ecc_tmp >> 24);

	ecc_tmp = readl(&regs->bank_regs[bank].sts);
	ecc[12] = (uint8_t) (ecc_tmp >> 16);

	return 0;
}

/*
 * fsmc_read_hwecc_ecc1 - Hardware ECC calculator for ecc1 option supported by
 * FSMC. ECC is 3 bytes for 512 bytes of data (supports error correction up to
 * max of 1-bit)
 */
static int fsmc_read_hwecc_ecc1(struct mtd_info *mtd, const uint8_t *data,
				uint8_t *ecc)
{
	struct fsmc_nand_data *host = container_of(mtd,
					struct fsmc_nand_data, mtd);
	struct fsmc_regs *regs = host->regs_va;
	uint32_t bank = host->bank;
	uint32_t ecc_tmp;

	ecc_tmp = readl(&regs->bank_regs[bank].ecc1);
	ecc[0] = (uint8_t) (ecc_tmp >> 0);
	ecc[1] = (uint8_t) (ecc_tmp >> 8);
	ecc[2] = (uint8_t) (ecc_tmp >> 16);

	return 0;
}

/*
 * fsmc_read_page_hwecc
 * @mtd:	mtd info structure
 * @chip:	nand chip info structure
 * @buf:	buffer to store read data
 * @page:	page number to read
 *
 * This routine is needed for fsmc version 8 as reading from NAND chip has to be
 * performed in a strict sequence as follows:
 * data(512 byte) -> ecc(13 byte)
 * After this read, fsmc hardware generates and reports error data bits(up to a
 * max of 8 bits)
 */
static int fsmc_read_page_hwecc(struct mtd_info *mtd, struct nand_chip *chip,
				 uint8_t *buf, int page)
{
	struct fsmc_nand_data *host = container_of(mtd,
					struct fsmc_nand_data, mtd);
	struct fsmc_eccplace *ecc_place = host->ecc_place;
	int i, j, s, stat, eccsize = chip->ecc.size;
	int eccbytes = chip->ecc.bytes;
	int eccsteps = chip->ecc.steps;
	uint8_t *p = buf;
	uint8_t *ecc_calc = chip->buffers->ecccalc;
	uint8_t *ecc_code = chip->buffers->ecccode;
	int off, len, group = 0;
	/*
	 * ecc_oob is intentionally taken as uint16_t. In 16bit devices, we
	 * end up reading 14 bytes (7 words) from oob. The local array is
	 * to maintain word alignment
	 */
	uint16_t ecc_oob[7];
	uint8_t *oob = (uint8_t *)&ecc_oob[0];

	for (i = 0, s = 0; s < eccsteps; s++, i += eccbytes, p += eccsize) {

		chip->cmdfunc(mtd, NAND_CMD_READ0, s * eccsize, page);
		chip->ecc.hwctl(mtd, NAND_ECC_READ);
		chip->read_buf(mtd, p, eccsize);

		for (j = 0; j < eccbytes;) {
			off = ecc_place->eccplace[group].offset;
			len = ecc_place->eccplace[group].length;
			group++;

			/*
			* length is intentionally kept a higher multiple of 2
			* to read at least 13 bytes even in case of 16 bit NAND
			* devices
			*/
			len = roundup(len, 2);
			chip->cmdfunc(mtd, NAND_CMD_READOOB, off, page);
			chip->read_buf(mtd, oob + j, len);
			j += len;
		}

		memcpy(&ecc_code[i], oob, 13);
		chip->ecc.calculate(mtd, p, &ecc_calc[i]);

		stat = chip->ecc.correct(mtd, p, &ecc_code[i], &ecc_calc[i]);
		if (stat < 0)
			mtd->ecc_stats.failed++;
		else
			mtd->ecc_stats.corrected += stat;
	}

	return 0;
}

/*
 * fsmc_correct_data
 * @mtd:	mtd info structure
 * @dat:	buffer of read data
 * @read_ecc:	ecc read from device spare area
 * @calc_ecc:	ecc calculated from read data
 *
 * calc_ecc is a 104 bit information containing maximum of 8 error
 * offset informations of 13 bits each in 512 bytes of read data.
 */
static int fsmc_correct_data(struct mtd_info *mtd, uint8_t *dat,
			     uint8_t *read_ecc, uint8_t *calc_ecc)
{
	struct fsmc_nand_data *host = container_of(mtd,
					struct fsmc_nand_data, mtd);
	struct fsmc_regs *regs = host->regs_va;
	unsigned int bank = host->bank;
	uint16_t err_idx[8];
	uint64_t ecc_data[2];
	uint32_t num_err, i;

	/* The calculated ecc is actually the correction index in data */
	memcpy(ecc_data, calc_ecc, 13);

	/*
	 * ------------------- calc_ecc[] bit wise -----------|--13 bits--|
	 * |---idx[7]--|--.....-----|---idx[2]--||---idx[1]--||---idx[0]--|
	 *
	 * calc_ecc is a 104 bit information containing maximum of 8 error
	 * offset informations of 13 bits each. calc_ecc is copied into a
	 * uint64_t array and error offset indexes are populated in err_idx
	 * array
	 */
	for (i = 0; i < 8; i++) {
		if (i == 4) {
			err_idx[4] = ((ecc_data[1] & 0x1) << 12) | ecc_data[0];
			ecc_data[1] >>= 1;
			continue;
		}
		err_idx[i] = (ecc_data[i/4] & 0x1FFF);
		ecc_data[i/4] >>= 13;
	}

	num_err = (readl(&regs->bank_regs[bank].sts) >> 10) & 0xF;

	if (num_err == 0xF)
		return -EBADMSG;

	i = 0;
	while (num_err--) {
		change_bit(0, (unsigned long *)&err_idx[i]);
		change_bit(1, (unsigned long *)&err_idx[i]);

		if (err_idx[i] <= 512 * 8) {
			change_bit(err_idx[i], (unsigned long *)dat);
			i++;
		}
	}
	return i;
}

/*
 * fsmc_nand_probe - Probe function
 * @pdev:       platform device structure
 */
static int __init fsmc_nand_probe(struct platform_device *pdev)
{
	struct fsmc_nand_platform_data *pdata = dev_get_platdata(&pdev->dev);
	struct fsmc_nand_data *host;
	struct mtd_info *mtd;
	struct nand_chip *nand;
	struct fsmc_regs *regs;
	struct resource *res;
	int ret = 0;
	u32 pid;
	int i;

	if (!pdata) {
		dev_err(&pdev->dev, "platform data is NULL\n");
		return -EINVAL;
	}

	/* Allocate memory for the device structure (and zero it) */
	host = kzalloc(sizeof(*host), GFP_KERNEL);
	if (!host) {
		dev_err(&pdev->dev, "failed to allocate device structure\n");
		return -ENOMEM;
	}

	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "nand_data");
	if (!res) {
		ret = -EIO;
		goto err_probe1;
	}

	host->resdata = request_mem_region(res->start, resource_size(res),
			pdev->name);
	if (!host->resdata) {
		ret = -EIO;
		goto err_probe1;
	}

	host->data_va = ioremap(res->start, resource_size(res));
	if (!host->data_va) {
		ret = -EIO;
		goto err_probe1;
	}

	host->resaddr = request_mem_region(res->start + PLAT_NAND_ALE,
			resource_size(res), pdev->name);
	if (!host->resaddr) {
		ret = -EIO;
		goto err_probe1;
	}

	host->addr_va = ioremap(res->start + PLAT_NAND_ALE, resource_size(res));
	if (!host->addr_va) {
		ret = -EIO;
		goto err_probe1;
	}

	host->rescmd = request_mem_region(res->start + PLAT_NAND_CLE,
			resource_size(res), pdev->name);
	if (!host->rescmd) {
		ret = -EIO;
		goto err_probe1;
	}

	host->cmd_va = ioremap(res->start + PLAT_NAND_CLE, resource_size(res));
	if (!host->cmd_va) {
		ret = -EIO;
		goto err_probe1;
	}

	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "fsmc_regs");
	if (!res) {
		ret = -EIO;
		goto err_probe1;
	}

	host->resregs = request_mem_region(res->start, resource_size(res),
			pdev->name);
	if (!host->resregs) {
		ret = -EIO;
		goto err_probe1;
	}

	host->regs_va = ioremap(res->start, resource_size(res));
	if (!host->regs_va) {
		ret = -EIO;
		goto err_probe1;
	}

	host->clk = clk_get(&pdev->dev, NULL);
	if (IS_ERR(host->clk)) {
		dev_err(&pdev->dev, "failed to fetch block clock\n");
		ret = PTR_ERR(host->clk);
		host->clk = NULL;
		goto err_probe1;
	}

	ret = clk_enable(host->clk);
	if (ret)
		goto err_probe1;

	/*
	 * This device ID is actually a common AMBA ID as used on the
	 * AMBA PrimeCell bus. However it is not a PrimeCell.
	 */
	for (pid = 0, i = 0; i < 4; i++)
		pid |= (readl(host->regs_va + resource_size(res) - 0x20 + 4 * i) & 255) << (i * 8);
	host->pid = pid;
	dev_info(&pdev->dev, "FSMC device partno %03x, manufacturer %02x, "
		 "revision %02x, config %02x\n",
		 AMBA_PART_BITS(pid), AMBA_MANF_BITS(pid),
		 AMBA_REV_BITS(pid), AMBA_CONFIG_BITS(pid));

	host->bank = pdata->bank;
	host->select_chip = pdata->select_bank;
	regs = host->regs_va;

	/* Link all private pointers */
	mtd = &host->mtd;
	nand = &host->nand;
	mtd->priv = nand;
	nand->priv = host;

	host->mtd.owner = THIS_MODULE;
	nand->IO_ADDR_R = host->data_va;
	nand->IO_ADDR_W = host->data_va;
	nand->cmd_ctrl = fsmc_cmd_ctrl;
	nand->chip_delay = 30;

	nand->ecc.mode = NAND_ECC_HW;
	nand->ecc.hwctl = fsmc_enable_hwecc;
	nand->ecc.size = 512;
	nand->options = pdata->options;
	nand->select_chip = fsmc_select_chip;

	if (pdata->width == FSMC_NAND_BW16)
		nand->options |= NAND_BUSWIDTH_16;

	fsmc_nand_setup(regs, host->bank, nand->options & NAND_BUSWIDTH_16);

	if (AMBA_REV_BITS(host->pid) >= 8) {
		nand->ecc.read_page = fsmc_read_page_hwecc;
		nand->ecc.calculate = fsmc_read_hwecc_ecc4;
		nand->ecc.correct = fsmc_correct_data;
		nand->ecc.bytes = 13;
	} else {
		nand->ecc.calculate = fsmc_read_hwecc_ecc1;
		nand->ecc.correct = nand_correct_data;
		nand->ecc.bytes = 3;
	}

	/*
	 * Scan to find existence of the device
	 */
	if (nand_scan_ident(&host->mtd, 1, NULL)) {
		ret = -ENXIO;
		dev_err(&pdev->dev, "No NAND Device found!\n");
		goto err_probe;
	}

	if (AMBA_REV_BITS(host->pid) >= 8) {
		if (host->mtd.writesize == 512) {
			nand->ecc.layout = &fsmc_ecc4_sp_layout;
			host->ecc_place = &fsmc_ecc4_sp_place;
		} else {
			nand->ecc.layout = &fsmc_ecc4_lp_layout;
			host->ecc_place = &fsmc_ecc4_lp_place;
		}
	} else {
		nand->ecc.layout = &fsmc_ecc1_layout;
	}

	/* Second stage of scan to fill MTD data-structures */
	if (nand_scan_tail(&host->mtd)) {
		ret = -ENXIO;
		goto err_probe;
	}

	/*
	 * The partition information can is accessed by (in the same precedence)
	 *
	 * command line through Bootloader,
	 * platform data,
	 * default partition information present in driver.
	 */
#ifdef CONFIG_MTD_PARTITIONS
#ifdef CONFIG_MTD_CMDLINE_PARTS
	/*
	 * Check if partition info passed via command line
	 */
	host->mtd.name = "nand";
	host->nr_partitions = parse_mtd_partitions(&host->mtd, part_probes,
			&host->partitions, 0);
	if (host->nr_partitions <= 0) {
#endif
		/*
		 * Check if partition info passed via command line
		 */
		if (pdata->partitions) {
			host->partitions = pdata->partitions;
			host->nr_partitions = pdata->nr_partitions;
		} else {
			struct mtd_partition *partition;
			int i;

			/* Select the default partitions info */
			switch (host->mtd.size) {
			case 0x01000000:
			case 0x02000000:
			case 0x04000000:
				host->partitions = partition_info_16KB_blk;
				host->nr_partitions =
					sizeof(partition_info_16KB_blk) /
					sizeof(struct mtd_partition);
				break;
			case 0x08000000:
			case 0x10000000:
			case 0x20000000:
			case 0x40000000:
				host->partitions = partition_info_128KB_blk;
				host->nr_partitions =
					sizeof(partition_info_128KB_blk) /
					sizeof(struct mtd_partition);
				break;
			default:
				ret = -ENXIO;
				pr_err("Unsupported NAND size\n");
				goto err_probe;
			}

			partition = host->partitions;
			for (i = 0; i < host->nr_partitions; i++, partition++) {
				if (partition->size == 0) {
					partition->size = host->mtd.size -
						partition->offset;
					break;
				}
			}
		}
#ifdef CONFIG_MTD_CMDLINE_PARTS
	}
#endif

	if (host->partitions) {
		ret = add_mtd_partitions(&host->mtd, host->partitions,
				host->nr_partitions);
		if (ret)
			goto err_probe;
	}
#else
	dev_info(&pdev->dev, "Registering %s as whole device\n", mtd->name);
	if (!add_mtd_device(mtd)) {
		ret = -ENXIO;
		goto err_probe;
	}
#endif

	platform_set_drvdata(pdev, host);
	dev_info(&pdev->dev, "FSMC NAND driver registration successful\n");
	return 0;

err_probe:
	clk_disable(host->clk);
err_probe1:
	if (host->clk)
		clk_put(host->clk);
	if (host->regs_va)
		iounmap(host->regs_va);
	if (host->resregs)
		release_mem_region(host->resregs->start,
				resource_size(host->resregs));
	if (host->cmd_va)
		iounmap(host->cmd_va);
	if (host->rescmd)
		release_mem_region(host->rescmd->start,
				resource_size(host->rescmd));
	if (host->addr_va)
		iounmap(host->addr_va);
	if (host->resaddr)
		release_mem_region(host->resaddr->start,
				resource_size(host->resaddr));
	if (host->data_va)
		iounmap(host->data_va);
	if (host->resdata)
		release_mem_region(host->resdata->start,
				resource_size(host->resdata));

	kfree(host);
	return ret;
}

/*
 * Clean up routine
 */
static int fsmc_nand_remove(struct platform_device *pdev)
{
	struct fsmc_nand_data *host = platform_get_drvdata(pdev);

	platform_set_drvdata(pdev, NULL);

	if (host) {
#ifdef CONFIG_MTD_PARTITIONS
		del_mtd_partitions(&host->mtd);
#else
		del_mtd_device(&host->mtd);
#endif
		clk_disable(host->clk);
		clk_put(host->clk);

		iounmap(host->regs_va);
		release_mem_region(host->resregs->start,
				resource_size(host->resregs));
		iounmap(host->cmd_va);
		release_mem_region(host->rescmd->start,
				resource_size(host->rescmd));
		iounmap(host->addr_va);
		release_mem_region(host->resaddr->start,
				resource_size(host->resaddr));
		iounmap(host->data_va);
		release_mem_region(host->resdata->start,
				resource_size(host->resdata));

		kfree(host);
	}
	return 0;
}

#ifdef CONFIG_PM
static int fsmc_nand_suspend(struct device *dev)
{
	struct fsmc_nand_data *host = dev_get_drvdata(dev);
	if (host)
		clk_disable(host->clk);
	return 0;
}

static int fsmc_nand_resume(struct device *dev)
{
	struct fsmc_nand_data *host = dev_get_drvdata(dev);
	if (host)
		clk_enable(host->clk);
	return 0;
}

static const struct dev_pm_ops fsmc_nand_pm_ops = {
	.suspend = fsmc_nand_suspend,
	.resume = fsmc_nand_resume,
};
#endif

static struct platform_driver fsmc_nand_driver = {
	.remove = fsmc_nand_remove,
	.driver = {
		.owner = THIS_MODULE,
		.name = "fsmc-nand",
#ifdef CONFIG_PM
		.pm = &fsmc_nand_pm_ops,
#endif
	},
};

static int __init fsmc_nand_init(void)
{
	return platform_driver_probe(&fsmc_nand_driver,
				     fsmc_nand_probe);
}
module_init(fsmc_nand_init);

static void __exit fsmc_nand_exit(void)
{
	platform_driver_unregister(&fsmc_nand_driver);
}
module_exit(fsmc_nand_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Vipin Kumar <vipin.kumar@st.com>, Ashish Priyadarshi");
MODULE_DESCRIPTION("NAND driver for SPEAr Platforms");