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1/*
2 * Copyright © 2004 Texas Instruments, Jian Zhang <jzhang@ti.com>
3 * Copyright © 2004 Micron Technology Inc.
4 * Copyright © 2004 David Brownell
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10
11#include <linux/platform_device.h>
12#include <linux/dmaengine.h>
13#include <linux/dma-mapping.h>
14#include <linux/delay.h>
15#include <linux/module.h>
16#include <linux/interrupt.h>
17#include <linux/jiffies.h>
18#include <linux/sched.h>
19#include <linux/mtd/mtd.h>
20#include <linux/mtd/nand.h>
21#include <linux/mtd/partitions.h>
22#include <linux/omap-dma.h>
23#include <linux/io.h>
24#include <linux/slab.h>
25#include <linux/of.h>
26#include <linux/of_device.h>
27
28#include <linux/mtd/nand_bch.h>
29#include <linux/platform_data/elm.h>
30
31#include <linux/platform_data/mtd-nand-omap2.h>
32
33#define	DRIVER_NAME	"omap2-nand"
34#define	OMAP_NAND_TIMEOUT_MS	5000
35
36#define NAND_Ecc_P1e		(1 << 0)
37#define NAND_Ecc_P2e		(1 << 1)
38#define NAND_Ecc_P4e		(1 << 2)
39#define NAND_Ecc_P8e		(1 << 3)
40#define NAND_Ecc_P16e		(1 << 4)
41#define NAND_Ecc_P32e		(1 << 5)
42#define NAND_Ecc_P64e		(1 << 6)
43#define NAND_Ecc_P128e		(1 << 7)
44#define NAND_Ecc_P256e		(1 << 8)
45#define NAND_Ecc_P512e		(1 << 9)
46#define NAND_Ecc_P1024e		(1 << 10)
47#define NAND_Ecc_P2048e		(1 << 11)
48
49#define NAND_Ecc_P1o		(1 << 16)
50#define NAND_Ecc_P2o		(1 << 17)
51#define NAND_Ecc_P4o		(1 << 18)
52#define NAND_Ecc_P8o		(1 << 19)
53#define NAND_Ecc_P16o		(1 << 20)
54#define NAND_Ecc_P32o		(1 << 21)
55#define NAND_Ecc_P64o		(1 << 22)
56#define NAND_Ecc_P128o		(1 << 23)
57#define NAND_Ecc_P256o		(1 << 24)
58#define NAND_Ecc_P512o		(1 << 25)
59#define NAND_Ecc_P1024o		(1 << 26)
60#define NAND_Ecc_P2048o		(1 << 27)
61
62#define TF(value)	(value ? 1 : 0)
63
64#define P2048e(a)	(TF(a & NAND_Ecc_P2048e)	<< 0)
65#define P2048o(a)	(TF(a & NAND_Ecc_P2048o)	<< 1)
66#define P1e(a)		(TF(a & NAND_Ecc_P1e)		<< 2)
67#define P1o(a)		(TF(a & NAND_Ecc_P1o)		<< 3)
68#define P2e(a)		(TF(a & NAND_Ecc_P2e)		<< 4)
69#define P2o(a)		(TF(a & NAND_Ecc_P2o)		<< 5)
70#define P4e(a)		(TF(a & NAND_Ecc_P4e)		<< 6)
71#define P4o(a)		(TF(a & NAND_Ecc_P4o)		<< 7)
72
73#define P8e(a)		(TF(a & NAND_Ecc_P8e)		<< 0)
74#define P8o(a)		(TF(a & NAND_Ecc_P8o)		<< 1)
75#define P16e(a)		(TF(a & NAND_Ecc_P16e)		<< 2)
76#define P16o(a)		(TF(a & NAND_Ecc_P16o)		<< 3)
77#define P32e(a)		(TF(a & NAND_Ecc_P32e)		<< 4)
78#define P32o(a)		(TF(a & NAND_Ecc_P32o)		<< 5)
79#define P64e(a)		(TF(a & NAND_Ecc_P64e)		<< 6)
80#define P64o(a)		(TF(a & NAND_Ecc_P64o)		<< 7)
81
82#define P128e(a)	(TF(a & NAND_Ecc_P128e)		<< 0)
83#define P128o(a)	(TF(a & NAND_Ecc_P128o)		<< 1)
84#define P256e(a)	(TF(a & NAND_Ecc_P256e)		<< 2)
85#define P256o(a)	(TF(a & NAND_Ecc_P256o)		<< 3)
86#define P512e(a)	(TF(a & NAND_Ecc_P512e)		<< 4)
87#define P512o(a)	(TF(a & NAND_Ecc_P512o)		<< 5)
88#define P1024e(a)	(TF(a & NAND_Ecc_P1024e)	<< 6)
89#define P1024o(a)	(TF(a & NAND_Ecc_P1024o)	<< 7)
90
91#define P8e_s(a)	(TF(a & NAND_Ecc_P8e)		<< 0)
92#define P8o_s(a)	(TF(a & NAND_Ecc_P8o)		<< 1)
93#define P16e_s(a)	(TF(a & NAND_Ecc_P16e)		<< 2)
94#define P16o_s(a)	(TF(a & NAND_Ecc_P16o)		<< 3)
95#define P1e_s(a)	(TF(a & NAND_Ecc_P1e)		<< 4)
96#define P1o_s(a)	(TF(a & NAND_Ecc_P1o)		<< 5)
97#define P2e_s(a)	(TF(a & NAND_Ecc_P2e)		<< 6)
98#define P2o_s(a)	(TF(a & NAND_Ecc_P2o)		<< 7)
99
100#define P4e_s(a)	(TF(a & NAND_Ecc_P4e)		<< 0)
101#define P4o_s(a)	(TF(a & NAND_Ecc_P4o)		<< 1)
102
103#define	PREFETCH_CONFIG1_CS_SHIFT	24
104#define	ECC_CONFIG_CS_SHIFT		1
105#define	CS_MASK				0x7
106#define	ENABLE_PREFETCH			(0x1 << 7)
107#define	DMA_MPU_MODE_SHIFT		2
108#define	ECCSIZE0_SHIFT			12
109#define	ECCSIZE1_SHIFT			22
110#define	ECC1RESULTSIZE			0x1
111#define	ECCCLEAR			0x100
112#define	ECC1				0x1
113#define	PREFETCH_FIFOTHRESHOLD_MAX	0x40
114#define	PREFETCH_FIFOTHRESHOLD(val)	((val) << 8)
115#define	PREFETCH_STATUS_COUNT(val)	(val & 0x00003fff)
116#define	PREFETCH_STATUS_FIFO_CNT(val)	((val >> 24) & 0x7F)
117#define	STATUS_BUFF_EMPTY		0x00000001
118
119#define OMAP24XX_DMA_GPMC		4
120
121#define SECTOR_BYTES		512
122/* 4 bit padding to make byte aligned, 56 = 52 + 4 */
123#define BCH4_BIT_PAD		4
124
125/* GPMC ecc engine settings for read */
126#define BCH_WRAPMODE_1		1	/* BCH wrap mode 1 */
127#define BCH8R_ECC_SIZE0		0x1a	/* ecc_size0 = 26 */
128#define BCH8R_ECC_SIZE1		0x2	/* ecc_size1 = 2 */
129#define BCH4R_ECC_SIZE0		0xd	/* ecc_size0 = 13 */
130#define BCH4R_ECC_SIZE1		0x3	/* ecc_size1 = 3 */
131
132/* GPMC ecc engine settings for write */
133#define BCH_WRAPMODE_6		6	/* BCH wrap mode 6 */
134#define BCH_ECC_SIZE0		0x0	/* ecc_size0 = 0, no oob protection */
135#define BCH_ECC_SIZE1		0x20	/* ecc_size1 = 32 */
136
137#define BADBLOCK_MARKER_LENGTH		2
138
139static u_char bch16_vector[] = {0xf5, 0x24, 0x1c, 0xd0, 0x61, 0xb3, 0xf1, 0x55,
140				0x2e, 0x2c, 0x86, 0xa3, 0xed, 0x36, 0x1b, 0x78,
141				0x48, 0x76, 0xa9, 0x3b, 0x97, 0xd1, 0x7a, 0x93,
142				0x07, 0x0e};
143static u_char bch8_vector[] = {0xf3, 0xdb, 0x14, 0x16, 0x8b, 0xd2, 0xbe, 0xcc,
144	0xac, 0x6b, 0xff, 0x99, 0x7b};
145static u_char bch4_vector[] = {0x00, 0x6b, 0x31, 0xdd, 0x41, 0xbc, 0x10};
146
147/* oob info generated runtime depending on ecc algorithm and layout selected */
148static struct nand_ecclayout omap_oobinfo;
149
150struct omap_nand_info {
151	struct nand_hw_control		controller;
152	struct omap_nand_platform_data	*pdata;
153	struct mtd_info			mtd;
154	struct nand_chip		nand;
155	struct platform_device		*pdev;
156
157	int				gpmc_cs;
158	unsigned long			phys_base;
159	enum omap_ecc			ecc_opt;
160	struct completion		comp;
161	struct dma_chan			*dma;
162	int				gpmc_irq_fifo;
163	int				gpmc_irq_count;
164	enum {
165		OMAP_NAND_IO_READ = 0,	/* read */
166		OMAP_NAND_IO_WRITE,	/* write */
167	} iomode;
168	u_char				*buf;
169	int					buf_len;
170	struct gpmc_nand_regs		reg;
171	/* fields specific for BCHx_HW ECC scheme */
172	struct device			*elm_dev;
173	struct device_node		*of_node;
174};
175
176/**
177 * omap_prefetch_enable - configures and starts prefetch transfer
178 * @cs: cs (chip select) number
179 * @fifo_th: fifo threshold to be used for read/ write
180 * @dma_mode: dma mode enable (1) or disable (0)
181 * @u32_count: number of bytes to be transferred
182 * @is_write: prefetch read(0) or write post(1) mode
183 */
184static int omap_prefetch_enable(int cs, int fifo_th, int dma_mode,
185	unsigned int u32_count, int is_write, struct omap_nand_info *info)
186{
187	u32 val;
188
189	if (fifo_th > PREFETCH_FIFOTHRESHOLD_MAX)
190		return -1;
191
192	if (readl(info->reg.gpmc_prefetch_control))
193		return -EBUSY;
194
195	/* Set the amount of bytes to be prefetched */
196	writel(u32_count, info->reg.gpmc_prefetch_config2);
197
198	/* Set dma/mpu mode, the prefetch read / post write and
199	 * enable the engine. Set which cs is has requested for.
200	 */
201	val = ((cs << PREFETCH_CONFIG1_CS_SHIFT) |
202		PREFETCH_FIFOTHRESHOLD(fifo_th) | ENABLE_PREFETCH |
203		(dma_mode << DMA_MPU_MODE_SHIFT) | (0x1 & is_write));
204	writel(val, info->reg.gpmc_prefetch_config1);
205
206	/*  Start the prefetch engine */
207	writel(0x1, info->reg.gpmc_prefetch_control);
208
209	return 0;
210}
211
212/**
213 * omap_prefetch_reset - disables and stops the prefetch engine
214 */
215static int omap_prefetch_reset(int cs, struct omap_nand_info *info)
216{
217	u32 config1;
218
219	/* check if the same module/cs is trying to reset */
220	config1 = readl(info->reg.gpmc_prefetch_config1);
221	if (((config1 >> PREFETCH_CONFIG1_CS_SHIFT) & CS_MASK) != cs)
222		return -EINVAL;
223
224	/* Stop the PFPW engine */
225	writel(0x0, info->reg.gpmc_prefetch_control);
226
227	/* Reset/disable the PFPW engine */
228	writel(0x0, info->reg.gpmc_prefetch_config1);
229
230	return 0;
231}
232
233/**
234 * omap_hwcontrol - hardware specific access to control-lines
235 * @mtd: MTD device structure
236 * @cmd: command to device
237 * @ctrl:
238 * NAND_NCE: bit 0 -> don't care
239 * NAND_CLE: bit 1 -> Command Latch
240 * NAND_ALE: bit 2 -> Address Latch
241 *
242 * NOTE: boards may use different bits for these!!
243 */
244static void omap_hwcontrol(struct mtd_info *mtd, int cmd, unsigned int ctrl)
245{
246	struct omap_nand_info *info = container_of(mtd,
247					struct omap_nand_info, mtd);
248
249	if (cmd != NAND_CMD_NONE) {
250		if (ctrl & NAND_CLE)
251			writeb(cmd, info->reg.gpmc_nand_command);
252
253		else if (ctrl & NAND_ALE)
254			writeb(cmd, info->reg.gpmc_nand_address);
255
256		else /* NAND_NCE */
257			writeb(cmd, info->reg.gpmc_nand_data);
258	}
259}
260
261/**
262 * omap_read_buf8 - read data from NAND controller into buffer
263 * @mtd: MTD device structure
264 * @buf: buffer to store date
265 * @len: number of bytes to read
266 */
267static void omap_read_buf8(struct mtd_info *mtd, u_char *buf, int len)
268{
269	struct nand_chip *nand = mtd->priv;
270
271	ioread8_rep(nand->IO_ADDR_R, buf, len);
272}
273
274/**
275 * omap_write_buf8 - write buffer to NAND controller
276 * @mtd: MTD device structure
277 * @buf: data buffer
278 * @len: number of bytes to write
279 */
280static void omap_write_buf8(struct mtd_info *mtd, const u_char *buf, int len)
281{
282	struct omap_nand_info *info = container_of(mtd,
283						struct omap_nand_info, mtd);
284	u_char *p = (u_char *)buf;
285	u32	status = 0;
286
287	while (len--) {
288		iowrite8(*p++, info->nand.IO_ADDR_W);
289		/* wait until buffer is available for write */
290		do {
291			status = readl(info->reg.gpmc_status) &
292					STATUS_BUFF_EMPTY;
293		} while (!status);
294	}
295}
296
297/**
298 * omap_read_buf16 - read data from NAND controller into buffer
299 * @mtd: MTD device structure
300 * @buf: buffer to store date
301 * @len: number of bytes to read
302 */
303static void omap_read_buf16(struct mtd_info *mtd, u_char *buf, int len)
304{
305	struct nand_chip *nand = mtd->priv;
306
307	ioread16_rep(nand->IO_ADDR_R, buf, len / 2);
308}
309
310/**
311 * omap_write_buf16 - write buffer to NAND controller
312 * @mtd: MTD device structure
313 * @buf: data buffer
314 * @len: number of bytes to write
315 */
316static void omap_write_buf16(struct mtd_info *mtd, const u_char * buf, int len)
317{
318	struct omap_nand_info *info = container_of(mtd,
319						struct omap_nand_info, mtd);
320	u16 *p = (u16 *) buf;
321	u32	status = 0;
322	/* FIXME try bursts of writesw() or DMA ... */
323	len >>= 1;
324
325	while (len--) {
326		iowrite16(*p++, info->nand.IO_ADDR_W);
327		/* wait until buffer is available for write */
328		do {
329			status = readl(info->reg.gpmc_status) &
330					STATUS_BUFF_EMPTY;
331		} while (!status);
332	}
333}
334
335/**
336 * omap_read_buf_pref - read data from NAND controller into buffer
337 * @mtd: MTD device structure
338 * @buf: buffer to store date
339 * @len: number of bytes to read
340 */
341static void omap_read_buf_pref(struct mtd_info *mtd, u_char *buf, int len)
342{
343	struct omap_nand_info *info = container_of(mtd,
344						struct omap_nand_info, mtd);
345	uint32_t r_count = 0;
346	int ret = 0;
347	u32 *p = (u32 *)buf;
348
349	/* take care of subpage reads */
350	if (len % 4) {
351		if (info->nand.options & NAND_BUSWIDTH_16)
352			omap_read_buf16(mtd, buf, len % 4);
353		else
354			omap_read_buf8(mtd, buf, len % 4);
355		p = (u32 *) (buf + len % 4);
356		len -= len % 4;
357	}
358
359	/* configure and start prefetch transfer */
360	ret = omap_prefetch_enable(info->gpmc_cs,
361			PREFETCH_FIFOTHRESHOLD_MAX, 0x0, len, 0x0, info);
362	if (ret) {
363		/* PFPW engine is busy, use cpu copy method */
364		if (info->nand.options & NAND_BUSWIDTH_16)
365			omap_read_buf16(mtd, (u_char *)p, len);
366		else
367			omap_read_buf8(mtd, (u_char *)p, len);
368	} else {
369		do {
370			r_count = readl(info->reg.gpmc_prefetch_status);
371			r_count = PREFETCH_STATUS_FIFO_CNT(r_count);
372			r_count = r_count >> 2;
373			ioread32_rep(info->nand.IO_ADDR_R, p, r_count);
374			p += r_count;
375			len -= r_count << 2;
376		} while (len);
377		/* disable and stop the PFPW engine */
378		omap_prefetch_reset(info->gpmc_cs, info);
379	}
380}
381
382/**
383 * omap_write_buf_pref - write buffer to NAND controller
384 * @mtd: MTD device structure
385 * @buf: data buffer
386 * @len: number of bytes to write
387 */
388static void omap_write_buf_pref(struct mtd_info *mtd,
389					const u_char *buf, int len)
390{
391	struct omap_nand_info *info = container_of(mtd,
392						struct omap_nand_info, mtd);
393	uint32_t w_count = 0;
394	int i = 0, ret = 0;
395	u16 *p = (u16 *)buf;
396	unsigned long tim, limit;
397	u32 val;
398
399	/* take care of subpage writes */
400	if (len % 2 != 0) {
401		writeb(*buf, info->nand.IO_ADDR_W);
402		p = (u16 *)(buf + 1);
403		len--;
404	}
405
406	/*  configure and start prefetch transfer */
407	ret = omap_prefetch_enable(info->gpmc_cs,
408			PREFETCH_FIFOTHRESHOLD_MAX, 0x0, len, 0x1, info);
409	if (ret) {
410		/* PFPW engine is busy, use cpu copy method */
411		if (info->nand.options & NAND_BUSWIDTH_16)
412			omap_write_buf16(mtd, (u_char *)p, len);
413		else
414			omap_write_buf8(mtd, (u_char *)p, len);
415	} else {
416		while (len) {
417			w_count = readl(info->reg.gpmc_prefetch_status);
418			w_count = PREFETCH_STATUS_FIFO_CNT(w_count);
419			w_count = w_count >> 1;
420			for (i = 0; (i < w_count) && len; i++, len -= 2)
421				iowrite16(*p++, info->nand.IO_ADDR_W);
422		}
423		/* wait for data to flushed-out before reset the prefetch */
424		tim = 0;
425		limit = (loops_per_jiffy *
426					msecs_to_jiffies(OMAP_NAND_TIMEOUT_MS));
427		do {
428			cpu_relax();
429			val = readl(info->reg.gpmc_prefetch_status);
430			val = PREFETCH_STATUS_COUNT(val);
431		} while (val && (tim++ < limit));
432
433		/* disable and stop the PFPW engine */
434		omap_prefetch_reset(info->gpmc_cs, info);
435	}
436}
437
438/*
439 * omap_nand_dma_callback: callback on the completion of dma transfer
440 * @data: pointer to completion data structure
441 */
442static void omap_nand_dma_callback(void *data)
443{
444	complete((struct completion *) data);
445}
446
447/*
448 * omap_nand_dma_transfer: configure and start dma transfer
449 * @mtd: MTD device structure
450 * @addr: virtual address in RAM of source/destination
451 * @len: number of data bytes to be transferred
452 * @is_write: flag for read/write operation
453 */
454static inline int omap_nand_dma_transfer(struct mtd_info *mtd, void *addr,
455					unsigned int len, int is_write)
456{
457	struct omap_nand_info *info = container_of(mtd,
458					struct omap_nand_info, mtd);
459	struct dma_async_tx_descriptor *tx;
460	enum dma_data_direction dir = is_write ? DMA_TO_DEVICE :
461							DMA_FROM_DEVICE;
462	struct scatterlist sg;
463	unsigned long tim, limit;
464	unsigned n;
465	int ret;
466	u32 val;
467
468	if (addr >= high_memory) {
469		struct page *p1;
470
471		if (((size_t)addr & PAGE_MASK) !=
472			((size_t)(addr + len - 1) & PAGE_MASK))
473			goto out_copy;
474		p1 = vmalloc_to_page(addr);
475		if (!p1)
476			goto out_copy;
477		addr = page_address(p1) + ((size_t)addr & ~PAGE_MASK);
478	}
479
480	sg_init_one(&sg, addr, len);
481	n = dma_map_sg(info->dma->device->dev, &sg, 1, dir);
482	if (n == 0) {
483		dev_err(&info->pdev->dev,
484			"Couldn't DMA map a %d byte buffer\n", len);
485		goto out_copy;
486	}
487
488	tx = dmaengine_prep_slave_sg(info->dma, &sg, n,
489		is_write ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM,
490		DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
491	if (!tx)
492		goto out_copy_unmap;
493
494	tx->callback = omap_nand_dma_callback;
495	tx->callback_param = &info->comp;
496	dmaengine_submit(tx);
497
498	/*  configure and start prefetch transfer */
499	ret = omap_prefetch_enable(info->gpmc_cs,
500		PREFETCH_FIFOTHRESHOLD_MAX, 0x1, len, is_write, info);
501	if (ret)
502		/* PFPW engine is busy, use cpu copy method */
503		goto out_copy_unmap;
504
505	init_completion(&info->comp);
506	dma_async_issue_pending(info->dma);
507
508	/* setup and start DMA using dma_addr */
509	wait_for_completion(&info->comp);
510	tim = 0;
511	limit = (loops_per_jiffy * msecs_to_jiffies(OMAP_NAND_TIMEOUT_MS));
512
513	do {
514		cpu_relax();
515		val = readl(info->reg.gpmc_prefetch_status);
516		val = PREFETCH_STATUS_COUNT(val);
517	} while (val && (tim++ < limit));
518
519	/* disable and stop the PFPW engine */
520	omap_prefetch_reset(info->gpmc_cs, info);
521
522	dma_unmap_sg(info->dma->device->dev, &sg, 1, dir);
523	return 0;
524
525out_copy_unmap:
526	dma_unmap_sg(info->dma->device->dev, &sg, 1, dir);
527out_copy:
528	if (info->nand.options & NAND_BUSWIDTH_16)
529		is_write == 0 ? omap_read_buf16(mtd, (u_char *) addr, len)
530			: omap_write_buf16(mtd, (u_char *) addr, len);
531	else
532		is_write == 0 ? omap_read_buf8(mtd, (u_char *) addr, len)
533			: omap_write_buf8(mtd, (u_char *) addr, len);
534	return 0;
535}
536
537/**
538 * omap_read_buf_dma_pref - read data from NAND controller into buffer
539 * @mtd: MTD device structure
540 * @buf: buffer to store date
541 * @len: number of bytes to read
542 */
543static void omap_read_buf_dma_pref(struct mtd_info *mtd, u_char *buf, int len)
544{
545	if (len <= mtd->oobsize)
546		omap_read_buf_pref(mtd, buf, len);
547	else
548		/* start transfer in DMA mode */
549		omap_nand_dma_transfer(mtd, buf, len, 0x0);
550}
551
552/**
553 * omap_write_buf_dma_pref - write buffer to NAND controller
554 * @mtd: MTD device structure
555 * @buf: data buffer
556 * @len: number of bytes to write
557 */
558static void omap_write_buf_dma_pref(struct mtd_info *mtd,
559					const u_char *buf, int len)
560{
561	if (len <= mtd->oobsize)
562		omap_write_buf_pref(mtd, buf, len);
563	else
564		/* start transfer in DMA mode */
565		omap_nand_dma_transfer(mtd, (u_char *) buf, len, 0x1);
566}
567
568/*
569 * omap_nand_irq - GPMC irq handler
570 * @this_irq: gpmc irq number
571 * @dev: omap_nand_info structure pointer is passed here
572 */
573static irqreturn_t omap_nand_irq(int this_irq, void *dev)
574{
575	struct omap_nand_info *info = (struct omap_nand_info *) dev;
576	u32 bytes;
577
578	bytes = readl(info->reg.gpmc_prefetch_status);
579	bytes = PREFETCH_STATUS_FIFO_CNT(bytes);
580	bytes = bytes  & 0xFFFC; /* io in multiple of 4 bytes */
581	if (info->iomode == OMAP_NAND_IO_WRITE) { /* checks for write io */
582		if (this_irq == info->gpmc_irq_count)
583			goto done;
584
585		if (info->buf_len && (info->buf_len < bytes))
586			bytes = info->buf_len;
587		else if (!info->buf_len)
588			bytes = 0;
589		iowrite32_rep(info->nand.IO_ADDR_W,
590						(u32 *)info->buf, bytes >> 2);
591		info->buf = info->buf + bytes;
592		info->buf_len -= bytes;
593
594	} else {
595		ioread32_rep(info->nand.IO_ADDR_R,
596						(u32 *)info->buf, bytes >> 2);
597		info->buf = info->buf + bytes;
598
599		if (this_irq == info->gpmc_irq_count)
600			goto done;
601	}
602
603	return IRQ_HANDLED;
604
605done:
606	complete(&info->comp);
607
608	disable_irq_nosync(info->gpmc_irq_fifo);
609	disable_irq_nosync(info->gpmc_irq_count);
610
611	return IRQ_HANDLED;
612}
613
614/*
615 * omap_read_buf_irq_pref - read data from NAND controller into buffer
616 * @mtd: MTD device structure
617 * @buf: buffer to store date
618 * @len: number of bytes to read
619 */
620static void omap_read_buf_irq_pref(struct mtd_info *mtd, u_char *buf, int len)
621{
622	struct omap_nand_info *info = container_of(mtd,
623						struct omap_nand_info, mtd);
624	int ret = 0;
625
626	if (len <= mtd->oobsize) {
627		omap_read_buf_pref(mtd, buf, len);
628		return;
629	}
630
631	info->iomode = OMAP_NAND_IO_READ;
632	info->buf = buf;
633	init_completion(&info->comp);
634
635	/*  configure and start prefetch transfer */
636	ret = omap_prefetch_enable(info->gpmc_cs,
637			PREFETCH_FIFOTHRESHOLD_MAX/2, 0x0, len, 0x0, info);
638	if (ret)
639		/* PFPW engine is busy, use cpu copy method */
640		goto out_copy;
641
642	info->buf_len = len;
643
644	enable_irq(info->gpmc_irq_count);
645	enable_irq(info->gpmc_irq_fifo);
646
647	/* waiting for read to complete */
648	wait_for_completion(&info->comp);
649
650	/* disable and stop the PFPW engine */
651	omap_prefetch_reset(info->gpmc_cs, info);
652	return;
653
654out_copy:
655	if (info->nand.options & NAND_BUSWIDTH_16)
656		omap_read_buf16(mtd, buf, len);
657	else
658		omap_read_buf8(mtd, buf, len);
659}
660
661/*
662 * omap_write_buf_irq_pref - write buffer to NAND controller
663 * @mtd: MTD device structure
664 * @buf: data buffer
665 * @len: number of bytes to write
666 */
667static void omap_write_buf_irq_pref(struct mtd_info *mtd,
668					const u_char *buf, int len)
669{
670	struct omap_nand_info *info = container_of(mtd,
671						struct omap_nand_info, mtd);
672	int ret = 0;
673	unsigned long tim, limit;
674	u32 val;
675
676	if (len <= mtd->oobsize) {
677		omap_write_buf_pref(mtd, buf, len);
678		return;
679	}
680
681	info->iomode = OMAP_NAND_IO_WRITE;
682	info->buf = (u_char *) buf;
683	init_completion(&info->comp);
684
685	/* configure and start prefetch transfer : size=24 */
686	ret = omap_prefetch_enable(info->gpmc_cs,
687		(PREFETCH_FIFOTHRESHOLD_MAX * 3) / 8, 0x0, len, 0x1, info);
688	if (ret)
689		/* PFPW engine is busy, use cpu copy method */
690		goto out_copy;
691
692	info->buf_len = len;
693
694	enable_irq(info->gpmc_irq_count);
695	enable_irq(info->gpmc_irq_fifo);
696
697	/* waiting for write to complete */
698	wait_for_completion(&info->comp);
699
700	/* wait for data to flushed-out before reset the prefetch */
701	tim = 0;
702	limit = (loops_per_jiffy *  msecs_to_jiffies(OMAP_NAND_TIMEOUT_MS));
703	do {
704		val = readl(info->reg.gpmc_prefetch_status);
705		val = PREFETCH_STATUS_COUNT(val);
706		cpu_relax();
707	} while (val && (tim++ < limit));
708
709	/* disable and stop the PFPW engine */
710	omap_prefetch_reset(info->gpmc_cs, info);
711	return;
712
713out_copy:
714	if (info->nand.options & NAND_BUSWIDTH_16)
715		omap_write_buf16(mtd, buf, len);
716	else
717		omap_write_buf8(mtd, buf, len);
718}
719
720/**
721 * gen_true_ecc - This function will generate true ECC value
722 * @ecc_buf: buffer to store ecc code
723 *
724 * This generated true ECC value can be used when correcting
725 * data read from NAND flash memory core
726 */
727static void gen_true_ecc(u8 *ecc_buf)
728{
729	u32 tmp = ecc_buf[0] | (ecc_buf[1] << 16) |
730		((ecc_buf[2] & 0xF0) << 20) | ((ecc_buf[2] & 0x0F) << 8);
731
732	ecc_buf[0] = ~(P64o(tmp) | P64e(tmp) | P32o(tmp) | P32e(tmp) |
733			P16o(tmp) | P16e(tmp) | P8o(tmp) | P8e(tmp));
734	ecc_buf[1] = ~(P1024o(tmp) | P1024e(tmp) | P512o(tmp) | P512e(tmp) |
735			P256o(tmp) | P256e(tmp) | P128o(tmp) | P128e(tmp));
736	ecc_buf[2] = ~(P4o(tmp) | P4e(tmp) | P2o(tmp) | P2e(tmp) | P1o(tmp) |
737			P1e(tmp) | P2048o(tmp) | P2048e(tmp));
738}
739
740/**
741 * omap_compare_ecc - Detect (2 bits) and correct (1 bit) error in data
742 * @ecc_data1:  ecc code from nand spare area
743 * @ecc_data2:  ecc code from hardware register obtained from hardware ecc
744 * @page_data:  page data
745 *
746 * This function compares two ECC's and indicates if there is an error.
747 * If the error can be corrected it will be corrected to the buffer.
748 * If there is no error, %0 is returned. If there is an error but it
749 * was corrected, %1 is returned. Otherwise, %-1 is returned.
750 */
751static int omap_compare_ecc(u8 *ecc_data1,	/* read from NAND memory */
752			    u8 *ecc_data2,	/* read from register */
753			    u8 *page_data)
754{
755	uint	i;
756	u8	tmp0_bit[8], tmp1_bit[8], tmp2_bit[8];
757	u8	comp0_bit[8], comp1_bit[8], comp2_bit[8];
758	u8	ecc_bit[24];
759	u8	ecc_sum = 0;
760	u8	find_bit = 0;
761	uint	find_byte = 0;
762	int	isEccFF;
763
764	isEccFF = ((*(u32 *)ecc_data1 & 0xFFFFFF) == 0xFFFFFF);
765
766	gen_true_ecc(ecc_data1);
767	gen_true_ecc(ecc_data2);
768
769	for (i = 0; i <= 2; i++) {
770		*(ecc_data1 + i) = ~(*(ecc_data1 + i));
771		*(ecc_data2 + i) = ~(*(ecc_data2 + i));
772	}
773
774	for (i = 0; i < 8; i++) {
775		tmp0_bit[i]     = *ecc_data1 % 2;
776		*ecc_data1	= *ecc_data1 / 2;
777	}
778
779	for (i = 0; i < 8; i++) {
780		tmp1_bit[i]	 = *(ecc_data1 + 1) % 2;
781		*(ecc_data1 + 1) = *(ecc_data1 + 1) / 2;
782	}
783
784	for (i = 0; i < 8; i++) {
785		tmp2_bit[i]	 = *(ecc_data1 + 2) % 2;
786		*(ecc_data1 + 2) = *(ecc_data1 + 2) / 2;
787	}
788
789	for (i = 0; i < 8; i++) {
790		comp0_bit[i]     = *ecc_data2 % 2;
791		*ecc_data2       = *ecc_data2 / 2;
792	}
793
794	for (i = 0; i < 8; i++) {
795		comp1_bit[i]     = *(ecc_data2 + 1) % 2;
796		*(ecc_data2 + 1) = *(ecc_data2 + 1) / 2;
797	}
798
799	for (i = 0; i < 8; i++) {
800		comp2_bit[i]     = *(ecc_data2 + 2) % 2;
801		*(ecc_data2 + 2) = *(ecc_data2 + 2) / 2;
802	}
803
804	for (i = 0; i < 6; i++)
805		ecc_bit[i] = tmp2_bit[i + 2] ^ comp2_bit[i + 2];
806
807	for (i = 0; i < 8; i++)
808		ecc_bit[i + 6] = tmp0_bit[i] ^ comp0_bit[i];
809
810	for (i = 0; i < 8; i++)
811		ecc_bit[i + 14] = tmp1_bit[i] ^ comp1_bit[i];
812
813	ecc_bit[22] = tmp2_bit[0] ^ comp2_bit[0];
814	ecc_bit[23] = tmp2_bit[1] ^ comp2_bit[1];
815
816	for (i = 0; i < 24; i++)
817		ecc_sum += ecc_bit[i];
818
819	switch (ecc_sum) {
820	case 0:
821		/* Not reached because this function is not called if
822		 *  ECC values are equal
823		 */
824		return 0;
825
826	case 1:
827		/* Uncorrectable error */
828		pr_debug("ECC UNCORRECTED_ERROR 1\n");
829		return -1;
830
831	case 11:
832		/* UN-Correctable error */
833		pr_debug("ECC UNCORRECTED_ERROR B\n");
834		return -1;
835
836	case 12:
837		/* Correctable error */
838		find_byte = (ecc_bit[23] << 8) +
839			    (ecc_bit[21] << 7) +
840			    (ecc_bit[19] << 6) +
841			    (ecc_bit[17] << 5) +
842			    (ecc_bit[15] << 4) +
843			    (ecc_bit[13] << 3) +
844			    (ecc_bit[11] << 2) +
845			    (ecc_bit[9]  << 1) +
846			    ecc_bit[7];
847
848		find_bit = (ecc_bit[5] << 2) + (ecc_bit[3] << 1) + ecc_bit[1];
849
850		pr_debug("Correcting single bit ECC error at offset: "
851				"%d, bit: %d\n", find_byte, find_bit);
852
853		page_data[find_byte] ^= (1 << find_bit);
854
855		return 1;
856	default:
857		if (isEccFF) {
858			if (ecc_data2[0] == 0 &&
859			    ecc_data2[1] == 0 &&
860			    ecc_data2[2] == 0)
861				return 0;
862		}
863		pr_debug("UNCORRECTED_ERROR default\n");
864		return -1;
865	}
866}
867
868/**
869 * omap_correct_data - Compares the ECC read with HW generated ECC
870 * @mtd: MTD device structure
871 * @dat: page data
872 * @read_ecc: ecc read from nand flash
873 * @calc_ecc: ecc read from HW ECC registers
874 *
875 * Compares the ecc read from nand spare area with ECC registers values
876 * and if ECC's mismatched, it will call 'omap_compare_ecc' for error
877 * detection and correction. If there are no errors, %0 is returned. If
878 * there were errors and all of the errors were corrected, the number of
879 * corrected errors is returned. If uncorrectable errors exist, %-1 is
880 * returned.
881 */
882static int omap_correct_data(struct mtd_info *mtd, u_char *dat,
883				u_char *read_ecc, u_char *calc_ecc)
884{
885	struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
886							mtd);
887	int blockCnt = 0, i = 0, ret = 0;
888	int stat = 0;
889
890	/* Ex NAND_ECC_HW12_2048 */
891	if ((info->nand.ecc.mode == NAND_ECC_HW) &&
892			(info->nand.ecc.size  == 2048))
893		blockCnt = 4;
894	else
895		blockCnt = 1;
896
897	for (i = 0; i < blockCnt; i++) {
898		if (memcmp(read_ecc, calc_ecc, 3) != 0) {
899			ret = omap_compare_ecc(read_ecc, calc_ecc, dat);
900			if (ret < 0)
901				return ret;
902			/* keep track of the number of corrected errors */
903			stat += ret;
904		}
905		read_ecc += 3;
906		calc_ecc += 3;
907		dat      += 512;
908	}
909	return stat;
910}
911
912/**
913 * omap_calcuate_ecc - Generate non-inverted ECC bytes.
914 * @mtd: MTD device structure
915 * @dat: The pointer to data on which ecc is computed
916 * @ecc_code: The ecc_code buffer
917 *
918 * Using noninverted ECC can be considered ugly since writing a blank
919 * page ie. padding will clear the ECC bytes. This is no problem as long
920 * nobody is trying to write data on the seemingly unused page. Reading
921 * an erased page will produce an ECC mismatch between generated and read
922 * ECC bytes that has to be dealt with separately.
923 */
924static int omap_calculate_ecc(struct mtd_info *mtd, const u_char *dat,
925				u_char *ecc_code)
926{
927	struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
928							mtd);
929	u32 val;
930
931	val = readl(info->reg.gpmc_ecc_config);
932	if (((val >> ECC_CONFIG_CS_SHIFT) & CS_MASK) != info->gpmc_cs)
933		return -EINVAL;
934
935	/* read ecc result */
936	val = readl(info->reg.gpmc_ecc1_result);
937	*ecc_code++ = val;          /* P128e, ..., P1e */
938	*ecc_code++ = val >> 16;    /* P128o, ..., P1o */
939	/* P2048o, P1024o, P512o, P256o, P2048e, P1024e, P512e, P256e */
940	*ecc_code++ = ((val >> 8) & 0x0f) | ((val >> 20) & 0xf0);
941
942	return 0;
943}
944
945/**
946 * omap_enable_hwecc - This function enables the hardware ecc functionality
947 * @mtd: MTD device structure
948 * @mode: Read/Write mode
949 */
950static void omap_enable_hwecc(struct mtd_info *mtd, int mode)
951{
952	struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
953							mtd);
954	struct nand_chip *chip = mtd->priv;
955	unsigned int dev_width = (chip->options & NAND_BUSWIDTH_16) ? 1 : 0;
956	u32 val;
957
958	/* clear ecc and enable bits */
959	val = ECCCLEAR | ECC1;
960	writel(val, info->reg.gpmc_ecc_control);
961
962	/* program ecc and result sizes */
963	val = ((((info->nand.ecc.size >> 1) - 1) << ECCSIZE1_SHIFT) |
964			 ECC1RESULTSIZE);
965	writel(val, info->reg.gpmc_ecc_size_config);
966
967	switch (mode) {
968	case NAND_ECC_READ:
969	case NAND_ECC_WRITE:
970		writel(ECCCLEAR | ECC1, info->reg.gpmc_ecc_control);
971		break;
972	case NAND_ECC_READSYN:
973		writel(ECCCLEAR, info->reg.gpmc_ecc_control);
974		break;
975	default:
976		dev_info(&info->pdev->dev,
977			"error: unrecognized Mode[%d]!\n", mode);
978		break;
979	}
980
981	/* (ECC 16 or 8 bit col) | ( CS  )  | ECC Enable */
982	val = (dev_width << 7) | (info->gpmc_cs << 1) | (0x1);
983	writel(val, info->reg.gpmc_ecc_config);
984}
985
986/**
987 * omap_wait - wait until the command is done
988 * @mtd: MTD device structure
989 * @chip: NAND Chip structure
990 *
991 * Wait function is called during Program and erase operations and
992 * the way it is called from MTD layer, we should wait till the NAND
993 * chip is ready after the programming/erase operation has completed.
994 *
995 * Erase can take up to 400ms and program up to 20ms according to
996 * general NAND and SmartMedia specs
997 */
998static int omap_wait(struct mtd_info *mtd, struct nand_chip *chip)
999{
1000	struct nand_chip *this = mtd->priv;
1001	struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
1002							mtd);
1003	unsigned long timeo = jiffies;
1004	int status, state = this->state;
1005
1006	if (state == FL_ERASING)
1007		timeo += msecs_to_jiffies(400);
1008	else
1009		timeo += msecs_to_jiffies(20);
1010
1011	writeb(NAND_CMD_STATUS & 0xFF, info->reg.gpmc_nand_command);
1012	while (time_before(jiffies, timeo)) {
1013		status = readb(info->reg.gpmc_nand_data);
1014		if (status & NAND_STATUS_READY)
1015			break;
1016		cond_resched();
1017	}
1018
1019	status = readb(info->reg.gpmc_nand_data);
1020	return status;
1021}
1022
1023/**
1024 * omap_dev_ready - calls the platform specific dev_ready function
1025 * @mtd: MTD device structure
1026 */
1027static int omap_dev_ready(struct mtd_info *mtd)
1028{
1029	unsigned int val = 0;
1030	struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
1031							mtd);
1032
1033	val = readl(info->reg.gpmc_status);
1034
1035	if ((val & 0x100) == 0x100) {
1036		return 1;
1037	} else {
1038		return 0;
1039	}
1040}
1041
1042/**
1043 * omap_enable_hwecc_bch - Program GPMC to perform BCH ECC calculation
1044 * @mtd: MTD device structure
1045 * @mode: Read/Write mode
1046 *
1047 * When using BCH, sector size is hardcoded to 512 bytes.
1048 * Using wrapping mode 6 both for reading and writing if ELM module not uses
1049 * for error correction.
1050 * On writing,
1051 * eccsize0 = 0  (no additional protected byte in spare area)
1052 * eccsize1 = 32 (skip 32 nibbles = 16 bytes per sector in spare area)
1053 */
1054static void __maybe_unused omap_enable_hwecc_bch(struct mtd_info *mtd, int mode)
1055{
1056	unsigned int bch_type;
1057	unsigned int dev_width, nsectors;
1058	struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
1059						   mtd);
1060	enum omap_ecc ecc_opt = info->ecc_opt;
1061	struct nand_chip *chip = mtd->priv;
1062	u32 val, wr_mode;
1063	unsigned int ecc_size1, ecc_size0;
1064
1065	/* GPMC configurations for calculating ECC */
1066	switch (ecc_opt) {
1067	case OMAP_ECC_BCH4_CODE_HW_DETECTION_SW:
1068		bch_type = 0;
1069		nsectors = 1;
1070		if (mode == NAND_ECC_READ) {
1071			wr_mode	  = BCH_WRAPMODE_6;
1072			ecc_size0 = BCH_ECC_SIZE0;
1073			ecc_size1 = BCH_ECC_SIZE1;
1074		} else {
1075			wr_mode   = BCH_WRAPMODE_6;
1076			ecc_size0 = BCH_ECC_SIZE0;
1077			ecc_size1 = BCH_ECC_SIZE1;
1078		}
1079		break;
1080	case OMAP_ECC_BCH4_CODE_HW:
1081		bch_type = 0;
1082		nsectors = chip->ecc.steps;
1083		if (mode == NAND_ECC_READ) {
1084			wr_mode	  = BCH_WRAPMODE_1;
1085			ecc_size0 = BCH4R_ECC_SIZE0;
1086			ecc_size1 = BCH4R_ECC_SIZE1;
1087		} else {
1088			wr_mode   = BCH_WRAPMODE_6;
1089			ecc_size0 = BCH_ECC_SIZE0;
1090			ecc_size1 = BCH_ECC_SIZE1;
1091		}
1092		break;
1093	case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW:
1094		bch_type = 1;
1095		nsectors = 1;
1096		if (mode == NAND_ECC_READ) {
1097			wr_mode	  = BCH_WRAPMODE_6;
1098			ecc_size0 = BCH_ECC_SIZE0;
1099			ecc_size1 = BCH_ECC_SIZE1;
1100		} else {
1101			wr_mode   = BCH_WRAPMODE_6;
1102			ecc_size0 = BCH_ECC_SIZE0;
1103			ecc_size1 = BCH_ECC_SIZE1;
1104		}
1105		break;
1106	case OMAP_ECC_BCH8_CODE_HW:
1107		bch_type = 1;
1108		nsectors = chip->ecc.steps;
1109		if (mode == NAND_ECC_READ) {
1110			wr_mode	  = BCH_WRAPMODE_1;
1111			ecc_size0 = BCH8R_ECC_SIZE0;
1112			ecc_size1 = BCH8R_ECC_SIZE1;
1113		} else {
1114			wr_mode   = BCH_WRAPMODE_6;
1115			ecc_size0 = BCH_ECC_SIZE0;
1116			ecc_size1 = BCH_ECC_SIZE1;
1117		}
1118		break;
1119	case OMAP_ECC_BCH16_CODE_HW:
1120		bch_type = 0x2;
1121		nsectors = chip->ecc.steps;
1122		if (mode == NAND_ECC_READ) {
1123			wr_mode	  = 0x01;
1124			ecc_size0 = 52; /* ECC bits in nibbles per sector */
1125			ecc_size1 = 0;  /* non-ECC bits in nibbles per sector */
1126		} else {
1127			wr_mode	  = 0x01;
1128			ecc_size0 = 0;  /* extra bits in nibbles per sector */
1129			ecc_size1 = 52; /* OOB bits in nibbles per sector */
1130		}
1131		break;
1132	default:
1133		return;
1134	}
1135
1136	writel(ECC1, info->reg.gpmc_ecc_control);
1137
1138	/* Configure ecc size for BCH */
1139	val = (ecc_size1 << ECCSIZE1_SHIFT) | (ecc_size0 << ECCSIZE0_SHIFT);
1140	writel(val, info->reg.gpmc_ecc_size_config);
1141
1142	dev_width = (chip->options & NAND_BUSWIDTH_16) ? 1 : 0;
1143
1144	/* BCH configuration */
1145	val = ((1                        << 16) | /* enable BCH */
1146	       (bch_type		 << 12) | /* BCH4/BCH8/BCH16 */
1147	       (wr_mode                  <<  8) | /* wrap mode */
1148	       (dev_width                <<  7) | /* bus width */
1149	       (((nsectors-1) & 0x7)     <<  4) | /* number of sectors */
1150	       (info->gpmc_cs            <<  1) | /* ECC CS */
1151	       (0x1));                            /* enable ECC */
1152
1153	writel(val, info->reg.gpmc_ecc_config);
1154
1155	/* Clear ecc and enable bits */
1156	writel(ECCCLEAR | ECC1, info->reg.gpmc_ecc_control);
1157}
1158
1159static u8  bch4_polynomial[] = {0x28, 0x13, 0xcc, 0x39, 0x96, 0xac, 0x7f};
1160static u8  bch8_polynomial[] = {0xef, 0x51, 0x2e, 0x09, 0xed, 0x93, 0x9a, 0xc2,
1161				0x97, 0x79, 0xe5, 0x24, 0xb5};
1162
1163/**
1164 * omap_calculate_ecc_bch - Generate bytes of ECC bytes
1165 * @mtd:	MTD device structure
1166 * @dat:	The pointer to data on which ecc is computed
1167 * @ecc_code:	The ecc_code buffer
1168 *
1169 * Support calculating of BCH4/8 ecc vectors for the page
1170 */
1171static int __maybe_unused omap_calculate_ecc_bch(struct mtd_info *mtd,
1172					const u_char *dat, u_char *ecc_calc)
1173{
1174	struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
1175						   mtd);
1176	int eccbytes	= info->nand.ecc.bytes;
1177	struct gpmc_nand_regs	*gpmc_regs = &info->reg;
1178	u8 *ecc_code;
1179	unsigned long nsectors, bch_val1, bch_val2, bch_val3, bch_val4;
1180	u32 val;
1181	int i, j;
1182
1183	nsectors = ((readl(info->reg.gpmc_ecc_config) >> 4) & 0x7) + 1;
1184	for (i = 0; i < nsectors; i++) {
1185		ecc_code = ecc_calc;
1186		switch (info->ecc_opt) {
1187		case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW:
1188		case OMAP_ECC_BCH8_CODE_HW:
1189			bch_val1 = readl(gpmc_regs->gpmc_bch_result0[i]);
1190			bch_val2 = readl(gpmc_regs->gpmc_bch_result1[i]);
1191			bch_val3 = readl(gpmc_regs->gpmc_bch_result2[i]);
1192			bch_val4 = readl(gpmc_regs->gpmc_bch_result3[i]);
1193			*ecc_code++ = (bch_val4 & 0xFF);
1194			*ecc_code++ = ((bch_val3 >> 24) & 0xFF);
1195			*ecc_code++ = ((bch_val3 >> 16) & 0xFF);
1196			*ecc_code++ = ((bch_val3 >> 8) & 0xFF);
1197			*ecc_code++ = (bch_val3 & 0xFF);
1198			*ecc_code++ = ((bch_val2 >> 24) & 0xFF);
1199			*ecc_code++ = ((bch_val2 >> 16) & 0xFF);
1200			*ecc_code++ = ((bch_val2 >> 8) & 0xFF);
1201			*ecc_code++ = (bch_val2 & 0xFF);
1202			*ecc_code++ = ((bch_val1 >> 24) & 0xFF);
1203			*ecc_code++ = ((bch_val1 >> 16) & 0xFF);
1204			*ecc_code++ = ((bch_val1 >> 8) & 0xFF);
1205			*ecc_code++ = (bch_val1 & 0xFF);
1206			break;
1207		case OMAP_ECC_BCH4_CODE_HW_DETECTION_SW:
1208		case OMAP_ECC_BCH4_CODE_HW:
1209			bch_val1 = readl(gpmc_regs->gpmc_bch_result0[i]);
1210			bch_val2 = readl(gpmc_regs->gpmc_bch_result1[i]);
1211			*ecc_code++ = ((bch_val2 >> 12) & 0xFF);
1212			*ecc_code++ = ((bch_val2 >> 4) & 0xFF);
1213			*ecc_code++ = ((bch_val2 & 0xF) << 4) |
1214				((bch_val1 >> 28) & 0xF);
1215			*ecc_code++ = ((bch_val1 >> 20) & 0xFF);
1216			*ecc_code++ = ((bch_val1 >> 12) & 0xFF);
1217			*ecc_code++ = ((bch_val1 >> 4) & 0xFF);
1218			*ecc_code++ = ((bch_val1 & 0xF) << 4);
1219			break;
1220		case OMAP_ECC_BCH16_CODE_HW:
1221			val = readl(gpmc_regs->gpmc_bch_result6[i]);
1222			ecc_code[0]  = ((val >>  8) & 0xFF);
1223			ecc_code[1]  = ((val >>  0) & 0xFF);
1224			val = readl(gpmc_regs->gpmc_bch_result5[i]);
1225			ecc_code[2]  = ((val >> 24) & 0xFF);
1226			ecc_code[3]  = ((val >> 16) & 0xFF);
1227			ecc_code[4]  = ((val >>  8) & 0xFF);
1228			ecc_code[5]  = ((val >>  0) & 0xFF);
1229			val = readl(gpmc_regs->gpmc_bch_result4[i]);
1230			ecc_code[6]  = ((val >> 24) & 0xFF);
1231			ecc_code[7]  = ((val >> 16) & 0xFF);
1232			ecc_code[8]  = ((val >>  8) & 0xFF);
1233			ecc_code[9]  = ((val >>  0) & 0xFF);
1234			val = readl(gpmc_regs->gpmc_bch_result3[i]);
1235			ecc_code[10] = ((val >> 24) & 0xFF);
1236			ecc_code[11] = ((val >> 16) & 0xFF);
1237			ecc_code[12] = ((val >>  8) & 0xFF);
1238			ecc_code[13] = ((val >>  0) & 0xFF);
1239			val = readl(gpmc_regs->gpmc_bch_result2[i]);
1240			ecc_code[14] = ((val >> 24) & 0xFF);
1241			ecc_code[15] = ((val >> 16) & 0xFF);
1242			ecc_code[16] = ((val >>  8) & 0xFF);
1243			ecc_code[17] = ((val >>  0) & 0xFF);
1244			val = readl(gpmc_regs->gpmc_bch_result1[i]);
1245			ecc_code[18] = ((val >> 24) & 0xFF);
1246			ecc_code[19] = ((val >> 16) & 0xFF);
1247			ecc_code[20] = ((val >>  8) & 0xFF);
1248			ecc_code[21] = ((val >>  0) & 0xFF);
1249			val = readl(gpmc_regs->gpmc_bch_result0[i]);
1250			ecc_code[22] = ((val >> 24) & 0xFF);
1251			ecc_code[23] = ((val >> 16) & 0xFF);
1252			ecc_code[24] = ((val >>  8) & 0xFF);
1253			ecc_code[25] = ((val >>  0) & 0xFF);
1254			break;
1255		default:
1256			return -EINVAL;
1257		}
1258
1259		/* ECC scheme specific syndrome customizations */
1260		switch (info->ecc_opt) {
1261		case OMAP_ECC_BCH4_CODE_HW_DETECTION_SW:
1262			/* Add constant polynomial to remainder, so that
1263			 * ECC of blank pages results in 0x0 on reading back */
1264			for (j = 0; j < eccbytes; j++)
1265				ecc_calc[j] ^= bch4_polynomial[j];
1266			break;
1267		case OMAP_ECC_BCH4_CODE_HW:
1268			/* Set  8th ECC byte as 0x0 for ROM compatibility */
1269			ecc_calc[eccbytes - 1] = 0x0;
1270			break;
1271		case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW:
1272			/* Add constant polynomial to remainder, so that
1273			 * ECC of blank pages results in 0x0 on reading back */
1274			for (j = 0; j < eccbytes; j++)
1275				ecc_calc[j] ^= bch8_polynomial[j];
1276			break;
1277		case OMAP_ECC_BCH8_CODE_HW:
1278			/* Set 14th ECC byte as 0x0 for ROM compatibility */
1279			ecc_calc[eccbytes - 1] = 0x0;
1280			break;
1281		case OMAP_ECC_BCH16_CODE_HW:
1282			break;
1283		default:
1284			return -EINVAL;
1285		}
1286
1287	ecc_calc += eccbytes;
1288	}
1289
1290	return 0;
1291}
1292
1293/**
1294 * erased_sector_bitflips - count bit flips
1295 * @data:	data sector buffer
1296 * @oob:	oob buffer
1297 * @info:	omap_nand_info
1298 *
1299 * Check the bit flips in erased page falls below correctable level.
1300 * If falls below, report the page as erased with correctable bit
1301 * flip, else report as uncorrectable page.
1302 */
1303static int erased_sector_bitflips(u_char *data, u_char *oob,
1304		struct omap_nand_info *info)
1305{
1306	int flip_bits = 0, i;
1307
1308	for (i = 0; i < info->nand.ecc.size; i++) {
1309		flip_bits += hweight8(~data[i]);
1310		if (flip_bits > info->nand.ecc.strength)
1311			return 0;
1312	}
1313
1314	for (i = 0; i < info->nand.ecc.bytes - 1; i++) {
1315		flip_bits += hweight8(~oob[i]);
1316		if (flip_bits > info->nand.ecc.strength)
1317			return 0;
1318	}
1319
1320	/*
1321	 * Bit flips falls in correctable level.
1322	 * Fill data area with 0xFF
1323	 */
1324	if (flip_bits) {
1325		memset(data, 0xFF, info->nand.ecc.size);
1326		memset(oob, 0xFF, info->nand.ecc.bytes);
1327	}
1328
1329	return flip_bits;
1330}
1331
1332/**
1333 * omap_elm_correct_data - corrects page data area in case error reported
1334 * @mtd:	MTD device structure
1335 * @data:	page data
1336 * @read_ecc:	ecc read from nand flash
1337 * @calc_ecc:	ecc read from HW ECC registers
1338 *
1339 * Calculated ecc vector reported as zero in case of non-error pages.
1340 * In case of non-zero ecc vector, first filter out erased-pages, and
1341 * then process data via ELM to detect bit-flips.
1342 */
1343static int omap_elm_correct_data(struct mtd_info *mtd, u_char *data,
1344				u_char *read_ecc, u_char *calc_ecc)
1345{
1346	struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
1347			mtd);
1348	struct nand_ecc_ctrl *ecc = &info->nand.ecc;
1349	int eccsteps = info->nand.ecc.steps;
1350	int i , j, stat = 0;
1351	int eccflag, actual_eccbytes;
1352	struct elm_errorvec err_vec[ERROR_VECTOR_MAX];
1353	u_char *ecc_vec = calc_ecc;
1354	u_char *spare_ecc = read_ecc;
1355	u_char *erased_ecc_vec;
1356	u_char *buf;
1357	int bitflip_count;
1358	bool is_error_reported = false;
1359	u32 bit_pos, byte_pos, error_max, pos;
1360	int err;
1361
1362	switch (info->ecc_opt) {
1363	case OMAP_ECC_BCH4_CODE_HW:
1364		/* omit  7th ECC byte reserved for ROM code compatibility */
1365		actual_eccbytes = ecc->bytes - 1;
1366		erased_ecc_vec = bch4_vector;
1367		break;
1368	case OMAP_ECC_BCH8_CODE_HW:
1369		/* omit 14th ECC byte reserved for ROM code compatibility */
1370		actual_eccbytes = ecc->bytes - 1;
1371		erased_ecc_vec = bch8_vector;
1372		break;
1373	case OMAP_ECC_BCH16_CODE_HW:
1374		actual_eccbytes = ecc->bytes;
1375		erased_ecc_vec = bch16_vector;
1376		break;
1377	default:
1378		dev_err(&info->pdev->dev, "invalid driver configuration\n");
1379		return -EINVAL;
1380	}
1381
1382	/* Initialize elm error vector to zero */
1383	memset(err_vec, 0, sizeof(err_vec));
1384
1385	for (i = 0; i < eccsteps ; i++) {
1386		eccflag = 0;	/* initialize eccflag */
1387
1388		/*
1389		 * Check any error reported,
1390		 * In case of error, non zero ecc reported.
1391		 */
1392		for (j = 0; j < actual_eccbytes; j++) {
1393			if (calc_ecc[j] != 0) {
1394				eccflag = 1; /* non zero ecc, error present */
1395				break;
1396			}
1397		}
1398
1399		if (eccflag == 1) {
1400			if (memcmp(calc_ecc, erased_ecc_vec,
1401						actual_eccbytes) == 0) {
1402				/*
1403				 * calc_ecc[] matches pattern for ECC(all 0xff)
1404				 * so this is definitely an erased-page
1405				 */
1406			} else {
1407				buf = &data[info->nand.ecc.size * i];
1408				/*
1409				 * count number of 0-bits in read_buf.
1410				 * This check can be removed once a similar
1411				 * check is introduced in generic NAND driver
1412				 */
1413				bitflip_count = erased_sector_bitflips(
1414						buf, read_ecc, info);
1415				if (bitflip_count) {
1416					/*
1417					 * number of 0-bits within ECC limits
1418					 * So this may be an erased-page
1419					 */
1420					stat += bitflip_count;
1421				} else {
1422					/*
1423					 * Too many 0-bits. It may be a
1424					 * - programmed-page, OR
1425					 * - erased-page with many bit-flips
1426					 * So this page requires check by ELM
1427					 */
1428					err_vec[i].error_reported = true;
1429					is_error_reported = true;
1430				}
1431			}
1432		}
1433
1434		/* Update the ecc vector */
1435		calc_ecc += ecc->bytes;
1436		read_ecc += ecc->bytes;
1437	}
1438
1439	/* Check if any error reported */
1440	if (!is_error_reported)
1441		return stat;
1442
1443	/* Decode BCH error using ELM module */
1444	elm_decode_bch_error_page(info->elm_dev, ecc_vec, err_vec);
1445
1446	err = 0;
1447	for (i = 0; i < eccsteps; i++) {
1448		if (err_vec[i].error_uncorrectable) {
1449			dev_err(&info->pdev->dev,
1450				"uncorrectable bit-flips found\n");
1451			err = -EBADMSG;
1452		} else if (err_vec[i].error_reported) {
1453			for (j = 0; j < err_vec[i].error_count; j++) {
1454				switch (info->ecc_opt) {
1455				case OMAP_ECC_BCH4_CODE_HW:
1456					/* Add 4 bits to take care of padding */
1457					pos = err_vec[i].error_loc[j] +
1458						BCH4_BIT_PAD;
1459					break;
1460				case OMAP_ECC_BCH8_CODE_HW:
1461				case OMAP_ECC_BCH16_CODE_HW:
1462					pos = err_vec[i].error_loc[j];
1463					break;
1464				default:
1465					return -EINVAL;
1466				}
1467				error_max = (ecc->size + actual_eccbytes) * 8;
1468				/* Calculate bit position of error */
1469				bit_pos = pos % 8;
1470
1471				/* Calculate byte position of error */
1472				byte_pos = (error_max - pos - 1) / 8;
1473
1474				if (pos < error_max) {
1475					if (byte_pos < 512) {
1476						pr_debug("bitflip@dat[%d]=%x\n",
1477						     byte_pos, data[byte_pos]);
1478						data[byte_pos] ^= 1 << bit_pos;
1479					} else {
1480						pr_debug("bitflip@oob[%d]=%x\n",
1481							(byte_pos - 512),
1482						     spare_ecc[byte_pos - 512]);
1483						spare_ecc[byte_pos - 512] ^=
1484							1 << bit_pos;
1485					}
1486				} else {
1487					dev_err(&info->pdev->dev,
1488						"invalid bit-flip @ %d:%d\n",
1489						byte_pos, bit_pos);
1490					err = -EBADMSG;
1491				}
1492			}
1493		}
1494
1495		/* Update number of correctable errors */
1496		stat += err_vec[i].error_count;
1497
1498		/* Update page data with sector size */
1499		data += ecc->size;
1500		spare_ecc += ecc->bytes;
1501	}
1502
1503	return (err) ? err : stat;
1504}
1505
1506/**
1507 * omap_write_page_bch - BCH ecc based write page function for entire page
1508 * @mtd:		mtd info structure
1509 * @chip:		nand chip info structure
1510 * @buf:		data buffer
1511 * @oob_required:	must write chip->oob_poi to OOB
1512 *
1513 * Custom write page method evolved to support multi sector writing in one shot
1514 */
1515static int omap_write_page_bch(struct mtd_info *mtd, struct nand_chip *chip,
1516				  const uint8_t *buf, int oob_required)
1517{
1518	int i;
1519	uint8_t *ecc_calc = chip->buffers->ecccalc;
1520	uint32_t *eccpos = chip->ecc.layout->eccpos;
1521
1522	/* Enable GPMC ecc engine */
1523	chip->ecc.hwctl(mtd, NAND_ECC_WRITE);
1524
1525	/* Write data */
1526	chip->write_buf(mtd, buf, mtd->writesize);
1527
1528	/* Update ecc vector from GPMC result registers */
1529	chip->ecc.calculate(mtd, buf, &ecc_calc[0]);
1530
1531	for (i = 0; i < chip->ecc.total; i++)
1532		chip->oob_poi[eccpos[i]] = ecc_calc[i];
1533
1534	/* Write ecc vector to OOB area */
1535	chip->write_buf(mtd, chip->oob_poi, mtd->oobsize);
1536	return 0;
1537}
1538
1539/**
1540 * omap_read_page_bch - BCH ecc based page read function for entire page
1541 * @mtd:		mtd info structure
1542 * @chip:		nand chip info structure
1543 * @buf:		buffer to store read data
1544 * @oob_required:	caller requires OOB data read to chip->oob_poi
1545 * @page:		page number to read
1546 *
1547 * For BCH ecc scheme, GPMC used for syndrome calculation and ELM module
1548 * used for error correction.
1549 * Custom method evolved to support ELM error correction & multi sector
1550 * reading. On reading page data area is read along with OOB data with
1551 * ecc engine enabled. ecc vector updated after read of OOB data.
1552 * For non error pages ecc vector reported as zero.
1553 */
1554static int omap_read_page_bch(struct mtd_info *mtd, struct nand_chip *chip,
1555				uint8_t *buf, int oob_required, int page)
1556{
1557	uint8_t *ecc_calc = chip->buffers->ecccalc;
1558	uint8_t *ecc_code = chip->buffers->ecccode;
1559	uint32_t *eccpos = chip->ecc.layout->eccpos;
1560	uint8_t *oob = &chip->oob_poi[eccpos[0]];
1561	uint32_t oob_pos = mtd->writesize + chip->ecc.layout->eccpos[0];
1562	int stat;
1563	unsigned int max_bitflips = 0;
1564
1565	/* Enable GPMC ecc engine */
1566	chip->ecc.hwctl(mtd, NAND_ECC_READ);
1567
1568	/* Read data */
1569	chip->read_buf(mtd, buf, mtd->writesize);
1570
1571	/* Read oob bytes */
1572	chip->cmdfunc(mtd, NAND_CMD_RNDOUT, oob_pos, -1);
1573	chip->read_buf(mtd, oob, chip->ecc.total);
1574
1575	/* Calculate ecc bytes */
1576	chip->ecc.calculate(mtd, buf, ecc_calc);
1577
1578	memcpy(ecc_code, &chip->oob_poi[eccpos[0]], chip->ecc.total);
1579
1580	stat = chip->ecc.correct(mtd, buf, ecc_code, ecc_calc);
1581
1582	if (stat < 0) {
1583		mtd->ecc_stats.failed++;
1584	} else {
1585		mtd->ecc_stats.corrected += stat;
1586		max_bitflips = max_t(unsigned int, max_bitflips, stat);
1587	}
1588
1589	return max_bitflips;
1590}
1591
1592/**
1593 * is_elm_present - checks for presence of ELM module by scanning DT nodes
1594 * @omap_nand_info: NAND device structure containing platform data
1595 */
1596static bool is_elm_present(struct omap_nand_info *info,
1597			   struct device_node *elm_node)
1598{
1599	struct platform_device *pdev;
1600
1601	/* check whether elm-id is passed via DT */
1602	if (!elm_node) {
1603		dev_err(&info->pdev->dev, "ELM devicetree node not found\n");
1604		return false;
1605	}
1606	pdev = of_find_device_by_node(elm_node);
1607	/* check whether ELM device is registered */
1608	if (!pdev) {
1609		dev_err(&info->pdev->dev, "ELM device not found\n");
1610		return false;
1611	}
1612	/* ELM module available, now configure it */
1613	info->elm_dev = &pdev->dev;
1614	return true;
1615}
1616
1617static bool omap2_nand_ecc_check(struct omap_nand_info *info,
1618				 struct omap_nand_platform_data	*pdata)
1619{
1620	bool ecc_needs_bch, ecc_needs_omap_bch, ecc_needs_elm;
1621
1622	switch (info->ecc_opt) {
1623	case OMAP_ECC_BCH4_CODE_HW_DETECTION_SW:
1624	case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW:
1625		ecc_needs_omap_bch = false;
1626		ecc_needs_bch = true;
1627		ecc_needs_elm = false;
1628		break;
1629	case OMAP_ECC_BCH4_CODE_HW:
1630	case OMAP_ECC_BCH8_CODE_HW:
1631	case OMAP_ECC_BCH16_CODE_HW:
1632		ecc_needs_omap_bch = true;
1633		ecc_needs_bch = false;
1634		ecc_needs_elm = true;
1635		break;
1636	default:
1637		ecc_needs_omap_bch = false;
1638		ecc_needs_bch = false;
1639		ecc_needs_elm = false;
1640		break;
1641	}
1642
1643	if (ecc_needs_bch && !IS_ENABLED(CONFIG_MTD_NAND_ECC_BCH)) {
1644		dev_err(&info->pdev->dev,
1645			"CONFIG_MTD_NAND_ECC_BCH not enabled\n");
1646		return false;
1647	}
1648	if (ecc_needs_omap_bch && !IS_ENABLED(CONFIG_MTD_NAND_OMAP_BCH)) {
1649		dev_err(&info->pdev->dev,
1650			"CONFIG_MTD_NAND_OMAP_BCH not enabled\n");
1651		return false;
1652	}
1653	if (ecc_needs_elm && !is_elm_present(info, pdata->elm_of_node)) {
1654		dev_err(&info->pdev->dev, "ELM not available\n");
1655		return false;
1656	}
1657
1658	return true;
1659}
1660
1661static int omap_nand_probe(struct platform_device *pdev)
1662{
1663	struct omap_nand_info		*info;
1664	struct omap_nand_platform_data	*pdata;
1665	struct mtd_info			*mtd;
1666	struct nand_chip		*nand_chip;
1667	struct nand_ecclayout		*ecclayout;
1668	int				err;
1669	int				i;
1670	dma_cap_mask_t			mask;
1671	unsigned			sig;
1672	unsigned			oob_index;
1673	struct resource			*res;
1674	struct mtd_part_parser_data	ppdata = {};
1675
1676	pdata = dev_get_platdata(&pdev->dev);
1677	if (pdata == NULL) {
1678		dev_err(&pdev->dev, "platform data missing\n");
1679		return -ENODEV;
1680	}
1681
1682	info = devm_kzalloc(&pdev->dev, sizeof(struct omap_nand_info),
1683				GFP_KERNEL);
1684	if (!info)
1685		return -ENOMEM;
1686
1687	platform_set_drvdata(pdev, info);
1688
1689	spin_lock_init(&info->controller.lock);
1690	init_waitqueue_head(&info->controller.wq);
1691
1692	info->pdev		= pdev;
1693	info->gpmc_cs		= pdata->cs;
1694	info->reg		= pdata->reg;
1695	info->of_node		= pdata->of_node;
1696	info->ecc_opt		= pdata->ecc_opt;
1697	mtd			= &info->mtd;
1698	mtd->priv		= &info->nand;
1699	mtd->name		= dev_name(&pdev->dev);
1700	mtd->owner		= THIS_MODULE;
1701	nand_chip		= &info->nand;
1702	nand_chip->ecc.priv	= NULL;
1703
1704	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1705	nand_chip->IO_ADDR_R = devm_ioremap_resource(&pdev->dev, res);
1706	if (IS_ERR(nand_chip->IO_ADDR_R))
1707		return PTR_ERR(nand_chip->IO_ADDR_R);
1708
1709	info->phys_base = res->start;
1710
1711	nand_chip->controller = &info->controller;
1712
1713	nand_chip->IO_ADDR_W = nand_chip->IO_ADDR_R;
1714	nand_chip->cmd_ctrl  = omap_hwcontrol;
1715
1716	/*
1717	 * If RDY/BSY line is connected to OMAP then use the omap ready
1718	 * function and the generic nand_wait function which reads the status
1719	 * register after monitoring the RDY/BSY line. Otherwise use a standard
1720	 * chip delay which is slightly more than tR (AC Timing) of the NAND
1721	 * device and read status register until you get a failure or success
1722	 */
1723	if (pdata->dev_ready) {
1724		nand_chip->dev_ready = omap_dev_ready;
1725		nand_chip->chip_delay = 0;
1726	} else {
1727		nand_chip->waitfunc = omap_wait;
1728		nand_chip->chip_delay = 50;
1729	}
1730
1731	if (pdata->flash_bbt)
1732		nand_chip->bbt_options |= NAND_BBT_USE_FLASH | NAND_BBT_NO_OOB;
1733	else
1734		nand_chip->options |= NAND_SKIP_BBTSCAN;
1735
1736	/* scan NAND device connected to chip controller */
1737	nand_chip->options |= pdata->devsize & NAND_BUSWIDTH_16;
1738	if (nand_scan_ident(mtd, 1, NULL)) {
1739		dev_err(&info->pdev->dev, "scan failed, may be bus-width mismatch\n");
1740		err = -ENXIO;
1741		goto return_error;
1742	}
1743
1744	/* check for small page devices */
1745	if ((mtd->oobsize < 64) && (pdata->ecc_opt != OMAP_ECC_HAM1_CODE_HW)) {
1746		dev_err(&info->pdev->dev, "small page devices are not supported\n");
1747		err = -EINVAL;
1748		goto return_error;
1749	}
1750
1751	/* re-populate low-level callbacks based on xfer modes */
1752	switch (pdata->xfer_type) {
1753	case NAND_OMAP_PREFETCH_POLLED:
1754		nand_chip->read_buf   = omap_read_buf_pref;
1755		nand_chip->write_buf  = omap_write_buf_pref;
1756		break;
1757
1758	case NAND_OMAP_POLLED:
1759		/* Use nand_base defaults for {read,write}_buf */
1760		break;
1761
1762	case NAND_OMAP_PREFETCH_DMA:
1763		dma_cap_zero(mask);
1764		dma_cap_set(DMA_SLAVE, mask);
1765		sig = OMAP24XX_DMA_GPMC;
1766		info->dma = dma_request_channel(mask, omap_dma_filter_fn, &sig);
1767		if (!info->dma) {
1768			dev_err(&pdev->dev, "DMA engine request failed\n");
1769			err = -ENXIO;
1770			goto return_error;
1771		} else {
1772			struct dma_slave_config cfg;
1773
1774			memset(&cfg, 0, sizeof(cfg));
1775			cfg.src_addr = info->phys_base;
1776			cfg.dst_addr = info->phys_base;
1777			cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1778			cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1779			cfg.src_maxburst = 16;
1780			cfg.dst_maxburst = 16;
1781			err = dmaengine_slave_config(info->dma, &cfg);
1782			if (err) {
1783				dev_err(&pdev->dev, "DMA engine slave config failed: %d\n",
1784					err);
1785				goto return_error;
1786			}
1787			nand_chip->read_buf   = omap_read_buf_dma_pref;
1788			nand_chip->write_buf  = omap_write_buf_dma_pref;
1789		}
1790		break;
1791
1792	case NAND_OMAP_PREFETCH_IRQ:
1793		info->gpmc_irq_fifo = platform_get_irq(pdev, 0);
1794		if (info->gpmc_irq_fifo <= 0) {
1795			dev_err(&pdev->dev, "error getting fifo irq\n");
1796			err = -ENODEV;
1797			goto return_error;
1798		}
1799		err = devm_request_irq(&pdev->dev, info->gpmc_irq_fifo,
1800					omap_nand_irq, IRQF_SHARED,
1801					"gpmc-nand-fifo", info);
1802		if (err) {
1803			dev_err(&pdev->dev, "requesting irq(%d) error:%d",
1804						info->gpmc_irq_fifo, err);
1805			info->gpmc_irq_fifo = 0;
1806			goto return_error;
1807		}
1808
1809		info->gpmc_irq_count = platform_get_irq(pdev, 1);
1810		if (info->gpmc_irq_count <= 0) {
1811			dev_err(&pdev->dev, "error getting count irq\n");
1812			err = -ENODEV;
1813			goto return_error;
1814		}
1815		err = devm_request_irq(&pdev->dev, info->gpmc_irq_count,
1816					omap_nand_irq, IRQF_SHARED,
1817					"gpmc-nand-count", info);
1818		if (err) {
1819			dev_err(&pdev->dev, "requesting irq(%d) error:%d",
1820						info->gpmc_irq_count, err);
1821			info->gpmc_irq_count = 0;
1822			goto return_error;
1823		}
1824
1825		nand_chip->read_buf  = omap_read_buf_irq_pref;
1826		nand_chip->write_buf = omap_write_buf_irq_pref;
1827
1828		break;
1829
1830	default:
1831		dev_err(&pdev->dev,
1832			"xfer_type(%d) not supported!\n", pdata->xfer_type);
1833		err = -EINVAL;
1834		goto return_error;
1835	}
1836
1837	if (!omap2_nand_ecc_check(info, pdata)) {
1838		err = -EINVAL;
1839		goto return_error;
1840	}
1841
1842	/* populate MTD interface based on ECC scheme */
1843	ecclayout		= &omap_oobinfo;
1844	switch (info->ecc_opt) {
1845	case OMAP_ECC_HAM1_CODE_SW:
1846		nand_chip->ecc.mode = NAND_ECC_SOFT;
1847		break;
1848
1849	case OMAP_ECC_HAM1_CODE_HW:
1850		pr_info("nand: using OMAP_ECC_HAM1_CODE_HW\n");
1851		nand_chip->ecc.mode             = NAND_ECC_HW;
1852		nand_chip->ecc.bytes            = 3;
1853		nand_chip->ecc.size             = 512;
1854		nand_chip->ecc.strength         = 1;
1855		nand_chip->ecc.calculate        = omap_calculate_ecc;
1856		nand_chip->ecc.hwctl            = omap_enable_hwecc;
1857		nand_chip->ecc.correct          = omap_correct_data;
1858		/* define ECC layout */
1859		ecclayout->eccbytes		= nand_chip->ecc.bytes *
1860							(mtd->writesize /
1861							nand_chip->ecc.size);
1862		if (nand_chip->options & NAND_BUSWIDTH_16)
1863			oob_index		= BADBLOCK_MARKER_LENGTH;
1864		else
1865			oob_index		= 1;
1866		for (i = 0; i < ecclayout->eccbytes; i++, oob_index++)
1867			ecclayout->eccpos[i]	= oob_index;
1868		/* no reserved-marker in ecclayout for this ecc-scheme */
1869		ecclayout->oobfree->offset	=
1870				ecclayout->eccpos[ecclayout->eccbytes - 1] + 1;
1871		break;
1872
1873	case OMAP_ECC_BCH4_CODE_HW_DETECTION_SW:
1874		pr_info("nand: using OMAP_ECC_BCH4_CODE_HW_DETECTION_SW\n");
1875		nand_chip->ecc.mode		= NAND_ECC_HW;
1876		nand_chip->ecc.size		= 512;
1877		nand_chip->ecc.bytes		= 7;
1878		nand_chip->ecc.strength		= 4;
1879		nand_chip->ecc.hwctl		= omap_enable_hwecc_bch;
1880		nand_chip->ecc.correct		= nand_bch_correct_data;
1881		nand_chip->ecc.calculate	= omap_calculate_ecc_bch;
1882		/* define ECC layout */
1883		ecclayout->eccbytes		= nand_chip->ecc.bytes *
1884							(mtd->writesize /
1885							nand_chip->ecc.size);
1886		oob_index			= BADBLOCK_MARKER_LENGTH;
1887		for (i = 0; i < ecclayout->eccbytes; i++, oob_index++) {
1888			ecclayout->eccpos[i] = oob_index;
1889			if (((i + 1) % nand_chip->ecc.bytes) == 0)
1890				oob_index++;
1891		}
1892		/* include reserved-marker in ecclayout->oobfree calculation */
1893		ecclayout->oobfree->offset	= 1 +
1894				ecclayout->eccpos[ecclayout->eccbytes - 1] + 1;
1895		/* software bch library is used for locating errors */
1896		nand_chip->ecc.priv		= nand_bch_init(mtd,
1897							nand_chip->ecc.size,
1898							nand_chip->ecc.bytes,
1899							&ecclayout);
1900		if (!nand_chip->ecc.priv) {
1901			dev_err(&info->pdev->dev, "unable to use BCH library\n");
1902			err = -EINVAL;
1903			goto return_error;
1904		}
1905		break;
1906
1907	case OMAP_ECC_BCH4_CODE_HW:
1908		pr_info("nand: using OMAP_ECC_BCH4_CODE_HW ECC scheme\n");
1909		nand_chip->ecc.mode		= NAND_ECC_HW;
1910		nand_chip->ecc.size		= 512;
1911		/* 14th bit is kept reserved for ROM-code compatibility */
1912		nand_chip->ecc.bytes		= 7 + 1;
1913		nand_chip->ecc.strength		= 4;
1914		nand_chip->ecc.hwctl		= omap_enable_hwecc_bch;
1915		nand_chip->ecc.correct		= omap_elm_correct_data;
1916		nand_chip->ecc.calculate	= omap_calculate_ecc_bch;
1917		nand_chip->ecc.read_page	= omap_read_page_bch;
1918		nand_chip->ecc.write_page	= omap_write_page_bch;
1919		/* define ECC layout */
1920		ecclayout->eccbytes		= nand_chip->ecc.bytes *
1921							(mtd->writesize /
1922							nand_chip->ecc.size);
1923		oob_index			= BADBLOCK_MARKER_LENGTH;
1924		for (i = 0; i < ecclayout->eccbytes; i++, oob_index++)
1925			ecclayout->eccpos[i]	= oob_index;
1926		/* reserved marker already included in ecclayout->eccbytes */
1927		ecclayout->oobfree->offset	=
1928				ecclayout->eccpos[ecclayout->eccbytes - 1] + 1;
1929
1930		err = elm_config(info->elm_dev, BCH4_ECC,
1931				 info->mtd.writesize / nand_chip->ecc.size,
1932				 nand_chip->ecc.size, nand_chip->ecc.bytes);
1933		if (err < 0)
1934			goto return_error;
1935		break;
1936
1937	case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW:
1938		pr_info("nand: using OMAP_ECC_BCH8_CODE_HW_DETECTION_SW\n");
1939		nand_chip->ecc.mode		= NAND_ECC_HW;
1940		nand_chip->ecc.size		= 512;
1941		nand_chip->ecc.bytes		= 13;
1942		nand_chip->ecc.strength		= 8;
1943		nand_chip->ecc.hwctl		= omap_enable_hwecc_bch;
1944		nand_chip->ecc.correct		= nand_bch_correct_data;
1945		nand_chip->ecc.calculate	= omap_calculate_ecc_bch;
1946		/* define ECC layout */
1947		ecclayout->eccbytes		= nand_chip->ecc.bytes *
1948							(mtd->writesize /
1949							nand_chip->ecc.size);
1950		oob_index			= BADBLOCK_MARKER_LENGTH;
1951		for (i = 0; i < ecclayout->eccbytes; i++, oob_index++) {
1952			ecclayout->eccpos[i] = oob_index;
1953			if (((i + 1) % nand_chip->ecc.bytes) == 0)
1954				oob_index++;
1955		}
1956		/* include reserved-marker in ecclayout->oobfree calculation */
1957		ecclayout->oobfree->offset	= 1 +
1958				ecclayout->eccpos[ecclayout->eccbytes - 1] + 1;
1959		/* software bch library is used for locating errors */
1960		nand_chip->ecc.priv		= nand_bch_init(mtd,
1961							nand_chip->ecc.size,
1962							nand_chip->ecc.bytes,
1963							&ecclayout);
1964		if (!nand_chip->ecc.priv) {
1965			dev_err(&info->pdev->dev, "unable to use BCH library\n");
1966			err = -EINVAL;
1967			goto return_error;
1968		}
1969		break;
1970
1971	case OMAP_ECC_BCH8_CODE_HW:
1972		pr_info("nand: using OMAP_ECC_BCH8_CODE_HW ECC scheme\n");
1973		nand_chip->ecc.mode		= NAND_ECC_HW;
1974		nand_chip->ecc.size		= 512;
1975		/* 14th bit is kept reserved for ROM-code compatibility */
1976		nand_chip->ecc.bytes		= 13 + 1;
1977		nand_chip->ecc.strength		= 8;
1978		nand_chip->ecc.hwctl		= omap_enable_hwecc_bch;
1979		nand_chip->ecc.correct		= omap_elm_correct_data;
1980		nand_chip->ecc.calculate	= omap_calculate_ecc_bch;
1981		nand_chip->ecc.read_page	= omap_read_page_bch;
1982		nand_chip->ecc.write_page	= omap_write_page_bch;
1983
1984		err = elm_config(info->elm_dev, BCH8_ECC,
1985				 info->mtd.writesize / nand_chip->ecc.size,
1986				 nand_chip->ecc.size, nand_chip->ecc.bytes);
1987		if (err < 0)
1988			goto return_error;
1989
1990		/* define ECC layout */
1991		ecclayout->eccbytes		= nand_chip->ecc.bytes *
1992							(mtd->writesize /
1993							nand_chip->ecc.size);
1994		oob_index			= BADBLOCK_MARKER_LENGTH;
1995		for (i = 0; i < ecclayout->eccbytes; i++, oob_index++)
1996			ecclayout->eccpos[i]	= oob_index;
1997		/* reserved marker already included in ecclayout->eccbytes */
1998		ecclayout->oobfree->offset	=
1999				ecclayout->eccpos[ecclayout->eccbytes - 1] + 1;
2000		break;
2001
2002	case OMAP_ECC_BCH16_CODE_HW:
2003		pr_info("using OMAP_ECC_BCH16_CODE_HW ECC scheme\n");
2004		nand_chip->ecc.mode		= NAND_ECC_HW;
2005		nand_chip->ecc.size		= 512;
2006		nand_chip->ecc.bytes		= 26;
2007		nand_chip->ecc.strength		= 16;
2008		nand_chip->ecc.hwctl		= omap_enable_hwecc_bch;
2009		nand_chip->ecc.correct		= omap_elm_correct_data;
2010		nand_chip->ecc.calculate	= omap_calculate_ecc_bch;
2011		nand_chip->ecc.read_page	= omap_read_page_bch;
2012		nand_chip->ecc.write_page	= omap_write_page_bch;
2013
2014		err = elm_config(info->elm_dev, BCH16_ECC,
2015				 info->mtd.writesize / nand_chip->ecc.size,
2016				 nand_chip->ecc.size, nand_chip->ecc.bytes);
2017		if (err < 0)
2018			goto return_error;
2019
2020		/* define ECC layout */
2021		ecclayout->eccbytes		= nand_chip->ecc.bytes *
2022							(mtd->writesize /
2023							nand_chip->ecc.size);
2024		oob_index			= BADBLOCK_MARKER_LENGTH;
2025		for (i = 0; i < ecclayout->eccbytes; i++, oob_index++)
2026			ecclayout->eccpos[i]	= oob_index;
2027		/* reserved marker already included in ecclayout->eccbytes */
2028		ecclayout->oobfree->offset	=
2029				ecclayout->eccpos[ecclayout->eccbytes - 1] + 1;
2030		break;
2031	default:
2032		dev_err(&info->pdev->dev, "invalid or unsupported ECC scheme\n");
2033		err = -EINVAL;
2034		goto return_error;
2035	}
2036
2037	if (info->ecc_opt == OMAP_ECC_HAM1_CODE_SW)
2038		goto scan_tail;
2039
2040	/* all OOB bytes from oobfree->offset till end off OOB are free */
2041	ecclayout->oobfree->length = mtd->oobsize - ecclayout->oobfree->offset;
2042	/* check if NAND device's OOB is enough to store ECC signatures */
2043	if (mtd->oobsize < (ecclayout->eccbytes + BADBLOCK_MARKER_LENGTH)) {
2044		dev_err(&info->pdev->dev,
2045			"not enough OOB bytes required = %d, available=%d\n",
2046			ecclayout->eccbytes, mtd->oobsize);
2047		err = -EINVAL;
2048		goto return_error;
2049	}
2050	nand_chip->ecc.layout = ecclayout;
2051
2052scan_tail:
2053	/* second phase scan */
2054	if (nand_scan_tail(mtd)) {
2055		err = -ENXIO;
2056		goto return_error;
2057	}
2058
2059	ppdata.of_node = pdata->of_node;
2060	mtd_device_parse_register(mtd, NULL, &ppdata, pdata->parts,
2061				  pdata->nr_parts);
2062
2063	platform_set_drvdata(pdev, mtd);
2064
2065	return 0;
2066
2067return_error:
2068	if (info->dma)
2069		dma_release_channel(info->dma);
2070	if (nand_chip->ecc.priv) {
2071		nand_bch_free(nand_chip->ecc.priv);
2072		nand_chip->ecc.priv = NULL;
2073	}
2074	return err;
2075}
2076
2077static int omap_nand_remove(struct platform_device *pdev)
2078{
2079	struct mtd_info *mtd = platform_get_drvdata(pdev);
2080	struct nand_chip *nand_chip = mtd->priv;
2081	struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
2082							mtd);
2083	if (nand_chip->ecc.priv) {
2084		nand_bch_free(nand_chip->ecc.priv);
2085		nand_chip->ecc.priv = NULL;
2086	}
2087	if (info->dma)
2088		dma_release_channel(info->dma);
2089	nand_release(mtd);
2090	return 0;
2091}
2092
2093static struct platform_driver omap_nand_driver = {
2094	.probe		= omap_nand_probe,
2095	.remove		= omap_nand_remove,
2096	.driver		= {
2097		.name	= DRIVER_NAME,
2098		.owner	= THIS_MODULE,
2099	},
2100};
2101
2102module_platform_driver(omap_nand_driver);
2103
2104MODULE_ALIAS("platform:" DRIVER_NAME);
2105MODULE_LICENSE("GPL");
2106MODULE_DESCRIPTION("Glue layer for NAND flash on TI OMAP boards");
2107