Initial file dump from open source releaseHEADmaster

1 files changed, 2120 insertions, 0 deletions

diff --git a/drivers/mtd/nand/omap2.c b/drivers/mtd/nand/omap2.c
new file mode 100644
index 00000000..e9b1797c
--- /dev/null
+++ b/drivers/mtd/nand/omap2.c
@@ -0,0 +1,2120 @@
+/*
+ * Copyright © 2004 Texas Instruments, Jian Zhang <jzhang@ti.com>
+ * Copyright © 2004 Micron Technology Inc.
+ * Copyright © 2004 David Brownell
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/platform_device.h>
+#include <linux/dmaengine.h>
+#include <linux/dma-mapping.h>
+#include <linux/delay.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/jiffies.h>
+#include <linux/sched.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/nand.h>
+#include <linux/mtd/partitions.h>
+#include <linux/omap-dma.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+
+#ifdef CONFIG_MTD_NAND_OMAP_BCH
+#include <linux/bch.h>
+#include <linux/platform_data/elm.h>
+#endif
+
+#include <linux/platform_data/mtd-nand-omap2.h>
+
+#define	DRIVER_NAME	"omap2-nand"
+#define	OMAP_NAND_TIMEOUT_MS	5000
+
+#define NAND_Ecc_P1e		(1 << 0)
+#define NAND_Ecc_P2e		(1 << 1)
+#define NAND_Ecc_P4e		(1 << 2)
+#define NAND_Ecc_P8e		(1 << 3)
+#define NAND_Ecc_P16e		(1 << 4)
+#define NAND_Ecc_P32e		(1 << 5)
+#define NAND_Ecc_P64e		(1 << 6)
+#define NAND_Ecc_P128e		(1 << 7)
+#define NAND_Ecc_P256e		(1 << 8)
+#define NAND_Ecc_P512e		(1 << 9)
+#define NAND_Ecc_P1024e		(1 << 10)
+#define NAND_Ecc_P2048e		(1 << 11)
+
+#define NAND_Ecc_P1o		(1 << 16)
+#define NAND_Ecc_P2o		(1 << 17)
+#define NAND_Ecc_P4o		(1 << 18)
+#define NAND_Ecc_P8o		(1 << 19)
+#define NAND_Ecc_P16o		(1 << 20)
+#define NAND_Ecc_P32o		(1 << 21)
+#define NAND_Ecc_P64o		(1 << 22)
+#define NAND_Ecc_P128o		(1 << 23)
+#define NAND_Ecc_P256o		(1 << 24)
+#define NAND_Ecc_P512o		(1 << 25)
+#define NAND_Ecc_P1024o		(1 << 26)
+#define NAND_Ecc_P2048o		(1 << 27)
+
+#define TF(value)	(value ? 1 : 0)
+
+#define P2048e(a)	(TF(a & NAND_Ecc_P2048e)	<< 0)
+#define P2048o(a)	(TF(a & NAND_Ecc_P2048o)	<< 1)
+#define P1e(a)		(TF(a & NAND_Ecc_P1e)		<< 2)
+#define P1o(a)		(TF(a & NAND_Ecc_P1o)		<< 3)
+#define P2e(a)		(TF(a & NAND_Ecc_P2e)		<< 4)
+#define P2o(a)		(TF(a & NAND_Ecc_P2o)		<< 5)
+#define P4e(a)		(TF(a & NAND_Ecc_P4e)		<< 6)
+#define P4o(a)		(TF(a & NAND_Ecc_P4o)		<< 7)
+
+#define P8e(a)		(TF(a & NAND_Ecc_P8e)		<< 0)
+#define P8o(a)		(TF(a & NAND_Ecc_P8o)		<< 1)
+#define P16e(a)		(TF(a & NAND_Ecc_P16e)		<< 2)
+#define P16o(a)		(TF(a & NAND_Ecc_P16o)		<< 3)
+#define P32e(a)		(TF(a & NAND_Ecc_P32e)		<< 4)
+#define P32o(a)		(TF(a & NAND_Ecc_P32o)		<< 5)
+#define P64e(a)		(TF(a & NAND_Ecc_P64e)		<< 6)
+#define P64o(a)		(TF(a & NAND_Ecc_P64o)		<< 7)
+
+#define P128e(a)	(TF(a & NAND_Ecc_P128e)		<< 0)
+#define P128o(a)	(TF(a & NAND_Ecc_P128o)		<< 1)
+#define P256e(a)	(TF(a & NAND_Ecc_P256e)		<< 2)
+#define P256o(a)	(TF(a & NAND_Ecc_P256o)		<< 3)
+#define P512e(a)	(TF(a & NAND_Ecc_P512e)		<< 4)
+#define P512o(a)	(TF(a & NAND_Ecc_P512o)		<< 5)
+#define P1024e(a)	(TF(a & NAND_Ecc_P1024e)	<< 6)
+#define P1024o(a)	(TF(a & NAND_Ecc_P1024o)	<< 7)
+
+#define P8e_s(a)	(TF(a & NAND_Ecc_P8e)		<< 0)
+#define P8o_s(a)	(TF(a & NAND_Ecc_P8o)		<< 1)
+#define P16e_s(a)	(TF(a & NAND_Ecc_P16e)		<< 2)
+#define P16o_s(a)	(TF(a & NAND_Ecc_P16o)		<< 3)
+#define P1e_s(a)	(TF(a & NAND_Ecc_P1e)		<< 4)
+#define P1o_s(a)	(TF(a & NAND_Ecc_P1o)		<< 5)
+#define P2e_s(a)	(TF(a & NAND_Ecc_P2e)		<< 6)
+#define P2o_s(a)	(TF(a & NAND_Ecc_P2o)		<< 7)
+
+#define P4e_s(a)	(TF(a & NAND_Ecc_P4e)		<< 0)
+#define P4o_s(a)	(TF(a & NAND_Ecc_P4o)		<< 1)
+
+#define	PREFETCH_CONFIG1_CS_SHIFT	24
+#define	ECC_CONFIG_CS_SHIFT		1
+#define	CS_MASK				0x7
+#define	ENABLE_PREFETCH			(0x1 << 7)
+#define	DMA_MPU_MODE_SHIFT		2
+#define	ECCSIZE0_SHIFT			12
+#define	ECCSIZE1_SHIFT			22
+#define	ECC1RESULTSIZE			0x1
+#define	ECCCLEAR			0x100
+#define	ECC1				0x1
+#define	PREFETCH_FIFOTHRESHOLD_MAX	0x40
+#define	PREFETCH_FIFOTHRESHOLD(val)	((val) << 8)
+#define	PREFETCH_STATUS_COUNT(val)	(val & 0x00003fff)
+#define	PREFETCH_STATUS_FIFO_CNT(val)	((val >> 24) & 0x7F)
+#define	STATUS_BUFF_EMPTY		0x00000001
+
+#define OMAP24XX_DMA_GPMC		4
+
+#define BCH8_MAX_ERROR		8	/* upto 8 bit correctable */
+#define BCH4_MAX_ERROR		4	/* upto 4 bit correctable */
+
+#define SECTOR_BYTES		512
+/* 4 bit padding to make byte aligned, 56 = 52 + 4 */
+#define BCH4_BIT_PAD		4
+#define BCH8_ECC_MAX		((SECTOR_BYTES + BCH8_ECC_OOB_BYTES) * 8)
+#define BCH4_ECC_MAX		((SECTOR_BYTES + BCH4_ECC_OOB_BYTES) * 8)
+
+/* GPMC ecc engine settings for read */
+#define BCH_WRAPMODE_1		1	/* BCH wrap mode 1 */
+#define BCH8R_ECC_SIZE0		0x1a	/* ecc_size0 = 26 */
+#define BCH8R_ECC_SIZE1		0x2	/* ecc_size1 = 2 */
+#define BCH4R_ECC_SIZE0		0xd	/* ecc_size0 = 13 */
+#define BCH4R_ECC_SIZE1		0x3	/* ecc_size1 = 3 */
+
+/* GPMC ecc engine settings for write */
+#define BCH_WRAPMODE_6		6	/* BCH wrap mode 6 */
+#define BCH_ECC_SIZE0		0x0	/* ecc_size0 = 0, no oob protection */
+#define BCH_ECC_SIZE1		0x20	/* ecc_size1 = 32 */
+
+#ifdef CONFIG_MTD_NAND_OMAP_BCH
+static u_char bch8_vector[] = {0xf3, 0xdb, 0x14, 0x16, 0x8b, 0xd2, 0xbe, 0xcc,
+	0xac, 0x6b, 0xff, 0x99, 0x7b};
+static u_char bch4_vector[] = {0x00, 0x6b, 0x31, 0xdd, 0x41, 0xbc, 0x10};
+#endif
+
+/* oob info generated runtime depending on ecc algorithm and layout selected */
+static struct nand_ecclayout omap_oobinfo;
+/* Define some generic bad / good block scan pattern which are used
+ * while scanning a device for factory marked good / bad blocks
+ */
+static uint8_t scan_ff_pattern[] = { 0xff };
+static struct nand_bbt_descr bb_descrip_flashbased = {
+	.options = NAND_BBT_SCANEMPTY | NAND_BBT_SCANALLPAGES,
+	.offs = 0,
+	.len = 1,
+	.pattern = scan_ff_pattern,
+};
+
+
+struct omap_nand_info {
+	struct nand_hw_control		controller;
+	struct omap_nand_platform_data	*pdata;
+	struct mtd_info			mtd;
+	struct nand_chip		nand;
+	struct platform_device		*pdev;
+
+	int				gpmc_cs;
+	unsigned long			phys_base;
+	unsigned long			mem_size;
+	struct completion		comp;
+	struct dma_chan			*dma;
+	int				gpmc_irq_fifo;
+	int				gpmc_irq_count;
+	enum {
+		OMAP_NAND_IO_READ = 0,	/* read */
+		OMAP_NAND_IO_WRITE,	/* write */
+	} iomode;
+	u_char				*buf;
+	int					buf_len;
+	struct gpmc_nand_regs		reg;
+
+#ifdef CONFIG_MTD_NAND_OMAP_BCH
+	struct bch_control             *bch;
+	struct nand_ecclayout           ecclayout;
+	bool				is_elm_used;
+	struct device			*elm_dev;
+	struct device_node		*of_node;
+#endif
+};
+
+/**
+ * omap_prefetch_enable - configures and starts prefetch transfer
+ * @cs: cs (chip select) number
+ * @fifo_th: fifo threshold to be used for read/ write
+ * @dma_mode: dma mode enable (1) or disable (0)
+ * @u32_count: number of bytes to be transferred
+ * @is_write: prefetch read(0) or write post(1) mode
+ */
+static int omap_prefetch_enable(int cs, int fifo_th, int dma_mode,
+	unsigned int u32_count, int is_write, struct omap_nand_info *info)
+{
+	u32 val;
+
+	if (fifo_th > PREFETCH_FIFOTHRESHOLD_MAX)
+		return -1;
+
+	if (readl(info->reg.gpmc_prefetch_control))
+		return -EBUSY;
+
+	/* Set the amount of bytes to be prefetched */
+	writel(u32_count, info->reg.gpmc_prefetch_config2);
+
+	/* Set dma/mpu mode, the prefetch read / post write and
+	 * enable the engine. Set which cs is has requested for.
+	 */
+	val = ((cs << PREFETCH_CONFIG1_CS_SHIFT) |
+		PREFETCH_FIFOTHRESHOLD(fifo_th) | ENABLE_PREFETCH |
+		(dma_mode << DMA_MPU_MODE_SHIFT) | (0x1 & is_write));
+	writel(val, info->reg.gpmc_prefetch_config1);
+
+	/*  Start the prefetch engine */
+	writel(0x1, info->reg.gpmc_prefetch_control);
+
+	return 0;
+}
+
+/**
+ * omap_prefetch_reset - disables and stops the prefetch engine
+ */
+static int omap_prefetch_reset(int cs, struct omap_nand_info *info)
+{
+	u32 config1;
+
+	/* check if the same module/cs is trying to reset */
+	config1 = readl(info->reg.gpmc_prefetch_config1);
+	if (((config1 >> PREFETCH_CONFIG1_CS_SHIFT) & CS_MASK) != cs)
+		return -EINVAL;
+
+	/* Stop the PFPW engine */
+	writel(0x0, info->reg.gpmc_prefetch_control);
+
+	/* Reset/disable the PFPW engine */
+	writel(0x0, info->reg.gpmc_prefetch_config1);
+
+	return 0;
+}
+
+/**
+ * omap_hwcontrol - hardware specific access to control-lines
+ * @mtd: MTD device structure
+ * @cmd: command to device
+ * @ctrl:
+ * NAND_NCE: bit 0 -> don't care
+ * NAND_CLE: bit 1 -> Command Latch
+ * NAND_ALE: bit 2 -> Address Latch
+ *
+ * NOTE: boards may use different bits for these!!
+ */
+static void omap_hwcontrol(struct mtd_info *mtd, int cmd, unsigned int ctrl)
+{
+	struct omap_nand_info *info = container_of(mtd,
+					struct omap_nand_info, mtd);
+
+	if (cmd != NAND_CMD_NONE) {
+		if (ctrl & NAND_CLE)
+			writeb(cmd, info->reg.gpmc_nand_command);
+
+		else if (ctrl & NAND_ALE)
+			writeb(cmd, info->reg.gpmc_nand_address);
+
+		else /* NAND_NCE */
+			writeb(cmd, info->reg.gpmc_nand_data);
+	}
+}
+
+/**
+ * omap_read_buf8 - read data from NAND controller into buffer
+ * @mtd: MTD device structure
+ * @buf: buffer to store date
+ * @len: number of bytes to read
+ */
+static void omap_read_buf8(struct mtd_info *mtd, u_char *buf, int len)
+{
+	struct nand_chip *nand = mtd->priv;
+
+	ioread8_rep(nand->IO_ADDR_R, buf, len);
+}
+
+/**
+ * omap_write_buf8 - write buffer to NAND controller
+ * @mtd: MTD device structure
+ * @buf: data buffer
+ * @len: number of bytes to write
+ */
+static void omap_write_buf8(struct mtd_info *mtd, const u_char *buf, int len)
+{
+	struct omap_nand_info *info = container_of(mtd,
+						struct omap_nand_info, mtd);
+	u_char *p = (u_char *)buf;
+	u32	status = 0;
+
+	while (len--) {
+		iowrite8(*p++, info->nand.IO_ADDR_W);
+		/* wait until buffer is available for write */
+		do {
+			status = readl(info->reg.gpmc_status) &
+					STATUS_BUFF_EMPTY;
+		} while (!status);
+	}
+}
+
+/**
+ * omap_read_buf16 - read data from NAND controller into buffer
+ * @mtd: MTD device structure
+ * @buf: buffer to store date
+ * @len: number of bytes to read
+ */
+static void omap_read_buf16(struct mtd_info *mtd, u_char *buf, int len)
+{
+	struct nand_chip *nand = mtd->priv;
+
+	ioread16_rep(nand->IO_ADDR_R, buf, len / 2);
+}
+
+/**
+ * omap_write_buf16 - write buffer to NAND controller
+ * @mtd: MTD device structure
+ * @buf: data buffer
+ * @len: number of bytes to write
+ */
+static void omap_write_buf16(struct mtd_info *mtd, const u_char * buf, int len)
+{
+	struct omap_nand_info *info = container_of(mtd,
+						struct omap_nand_info, mtd);
+	u16 *p = (u16 *) buf;
+	u32	status = 0;
+	/* FIXME try bursts of writesw() or DMA ... */
+	len >>= 1;
+
+	while (len--) {
+		iowrite16(*p++, info->nand.IO_ADDR_W);
+		/* wait until buffer is available for write */
+		do {
+			status = readl(info->reg.gpmc_status) &
+					STATUS_BUFF_EMPTY;
+		} while (!status);
+	}
+}
+
+/**
+ * omap_read_buf_pref - read data from NAND controller into buffer
+ * @mtd: MTD device structure
+ * @buf: buffer to store date
+ * @len: number of bytes to read
+ */
+static void omap_read_buf_pref(struct mtd_info *mtd, u_char *buf, int len)
+{
+	struct omap_nand_info *info = container_of(mtd,
+						struct omap_nand_info, mtd);
+	uint32_t r_count = 0;
+	int ret = 0;
+	u32 *p = (u32 *)buf;
+
+	/* take care of subpage reads */
+	if (len % 4) {
+		if (info->nand.options & NAND_BUSWIDTH_16)
+			omap_read_buf16(mtd, buf, len % 4);
+		else
+			omap_read_buf8(mtd, buf, len % 4);
+		p = (u32 *) (buf + len % 4);
+		len -= len % 4;
+	}
+
+	/* configure and start prefetch transfer */
+	ret = omap_prefetch_enable(info->gpmc_cs,
+			PREFETCH_FIFOTHRESHOLD_MAX, 0x0, len, 0x0, info);
+	if (ret) {
+		/* PFPW engine is busy, use cpu copy method */
+		if (info->nand.options & NAND_BUSWIDTH_16)
+			omap_read_buf16(mtd, (u_char *)p, len);
+		else
+			omap_read_buf8(mtd, (u_char *)p, len);
+	} else {
+		do {
+			r_count = readl(info->reg.gpmc_prefetch_status);
+			r_count = PREFETCH_STATUS_FIFO_CNT(r_count);
+			r_count = r_count >> 2;
+			ioread32_rep(info->nand.IO_ADDR_R, p, r_count);
+			p += r_count;
+			len -= r_count << 2;
+		} while (len);
+		/* disable and stop the PFPW engine */
+		omap_prefetch_reset(info->gpmc_cs, info);
+	}
+}
+
+/**
+ * omap_write_buf_pref - write buffer to NAND controller
+ * @mtd: MTD device structure
+ * @buf: data buffer
+ * @len: number of bytes to write
+ */
+static void omap_write_buf_pref(struct mtd_info *mtd,
+					const u_char *buf, int len)
+{
+	struct omap_nand_info *info = container_of(mtd,
+						struct omap_nand_info, mtd);
+	uint32_t w_count = 0;
+	int i = 0, ret = 0;
+	u16 *p = (u16 *)buf;
+	unsigned long tim, limit;
+	u32 val;
+
+	/* take care of subpage writes */
+	if (len % 2 != 0) {
+		writeb(*buf, info->nand.IO_ADDR_W);
+		p = (u16 *)(buf + 1);
+		len--;
+	}
+
+	/*  configure and start prefetch transfer */
+	ret = omap_prefetch_enable(info->gpmc_cs,
+			PREFETCH_FIFOTHRESHOLD_MAX, 0x0, len, 0x1, info);
+	if (ret) {
+		/* PFPW engine is busy, use cpu copy method */
+		if (info->nand.options & NAND_BUSWIDTH_16)
+			omap_write_buf16(mtd, (u_char *)p, len);
+		else
+			omap_write_buf8(mtd, (u_char *)p, len);
+	} else {
+		while (len) {
+			w_count = readl(info->reg.gpmc_prefetch_status);
+			w_count = PREFETCH_STATUS_FIFO_CNT(w_count);
+			w_count = w_count >> 1;
+			for (i = 0; (i < w_count) && len; i++, len -= 2)
+				iowrite16(*p++, info->nand.IO_ADDR_W);
+		}
+		/* wait for data to flushed-out before reset the prefetch */
+		tim = 0;
+		limit = (loops_per_jiffy *
+					msecs_to_jiffies(OMAP_NAND_TIMEOUT_MS));
+		do {
+			cpu_relax();
+			val = readl(info->reg.gpmc_prefetch_status);
+			val = PREFETCH_STATUS_COUNT(val);
+		} while (val && (tim++ < limit));
+
+		/* disable and stop the PFPW engine */
+		omap_prefetch_reset(info->gpmc_cs, info);
+	}
+}
+
+/*
+ * omap_nand_dma_callback: callback on the completion of dma transfer
+ * @data: pointer to completion data structure
+ */
+static void omap_nand_dma_callback(void *data)
+{
+	complete((struct completion *) data);
+}
+
+/*
+ * omap_nand_dma_transfer: configure and start dma transfer
+ * @mtd: MTD device structure
+ * @addr: virtual address in RAM of source/destination
+ * @len: number of data bytes to be transferred
+ * @is_write: flag for read/write operation
+ */
+static inline int omap_nand_dma_transfer(struct mtd_info *mtd, void *addr,
+					unsigned int len, int is_write)
+{
+	struct omap_nand_info *info = container_of(mtd,
+					struct omap_nand_info, mtd);
+	struct dma_async_tx_descriptor *tx;
+	enum dma_data_direction dir = is_write ? DMA_TO_DEVICE :
+							DMA_FROM_DEVICE;
+	struct scatterlist sg;
+	unsigned long tim, limit;
+	unsigned n;
+	int ret;
+	u32 val;
+
+	if (addr >= high_memory) {
+		struct page *p1;
+
+		if (((size_t)addr & PAGE_MASK) !=
+			((size_t)(addr + len - 1) & PAGE_MASK))
+			goto out_copy;
+		p1 = vmalloc_to_page(addr);
+		if (!p1)
+			goto out_copy;
+		addr = page_address(p1) + ((size_t)addr & ~PAGE_MASK);
+	}
+
+	sg_init_one(&sg, addr, len);
+	n = dma_map_sg(info->dma->device->dev, &sg, 1, dir);
+	if (n == 0) {
+		dev_err(&info->pdev->dev,
+			"Couldn't DMA map a %d byte buffer\n", len);
+		goto out_copy;
+	}
+
+	tx = dmaengine_prep_slave_sg(info->dma, &sg, n,
+		is_write ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM,
+		DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+	if (!tx)
+		goto out_copy_unmap;
+
+	tx->callback = omap_nand_dma_callback;
+	tx->callback_param = &info->comp;
+	dmaengine_submit(tx);
+
+	/*  configure and start prefetch transfer */
+	ret = omap_prefetch_enable(info->gpmc_cs,
+		PREFETCH_FIFOTHRESHOLD_MAX, 0x1, len, is_write, info);
+	if (ret)
+		/* PFPW engine is busy, use cpu copy method */
+		goto out_copy_unmap;
+
+	init_completion(&info->comp);
+	dma_async_issue_pending(info->dma);
+
+	/* setup and start DMA using dma_addr */
+	wait_for_completion(&info->comp);
+	tim = 0;
+	limit = (loops_per_jiffy * msecs_to_jiffies(OMAP_NAND_TIMEOUT_MS));
+
+	do {
+		cpu_relax();
+		val = readl(info->reg.gpmc_prefetch_status);
+		val = PREFETCH_STATUS_COUNT(val);
+	} while (val && (tim++ < limit));
+
+	/* disable and stop the PFPW engine */
+	omap_prefetch_reset(info->gpmc_cs, info);
+
+	dma_unmap_sg(info->dma->device->dev, &sg, 1, dir);
+	return 0;
+
+out_copy_unmap:
+	dma_unmap_sg(info->dma->device->dev, &sg, 1, dir);
+out_copy:
+	if (info->nand.options & NAND_BUSWIDTH_16)
+		is_write == 0 ? omap_read_buf16(mtd, (u_char *) addr, len)
+			: omap_write_buf16(mtd, (u_char *) addr, len);
+	else
+		is_write == 0 ? omap_read_buf8(mtd, (u_char *) addr, len)
+			: omap_write_buf8(mtd, (u_char *) addr, len);
+	return 0;
+}
+
+/**
+ * omap_read_buf_dma_pref - read data from NAND controller into buffer
+ * @mtd: MTD device structure
+ * @buf: buffer to store date
+ * @len: number of bytes to read
+ */
+static void omap_read_buf_dma_pref(struct mtd_info *mtd, u_char *buf, int len)
+{
+	if (len <= mtd->oobsize)
+		omap_read_buf_pref(mtd, buf, len);
+	else
+		/* start transfer in DMA mode */
+		omap_nand_dma_transfer(mtd, buf, len, 0x0);
+}
+
+/**
+ * omap_write_buf_dma_pref - write buffer to NAND controller
+ * @mtd: MTD device structure
+ * @buf: data buffer
+ * @len: number of bytes to write
+ */
+static void omap_write_buf_dma_pref(struct mtd_info *mtd,
+					const u_char *buf, int len)
+{
+	if (len <= mtd->oobsize)
+		omap_write_buf_pref(mtd, buf, len);
+	else
+		/* start transfer in DMA mode */
+		omap_nand_dma_transfer(mtd, (u_char *) buf, len, 0x1);
+}
+
+/*
+ * omap_nand_irq - GPMC irq handler
+ * @this_irq: gpmc irq number
+ * @dev: omap_nand_info structure pointer is passed here
+ */
+static irqreturn_t omap_nand_irq(int this_irq, void *dev)
+{
+	struct omap_nand_info *info = (struct omap_nand_info *) dev;
+	u32 bytes;
+
+	bytes = readl(info->reg.gpmc_prefetch_status);
+	bytes = PREFETCH_STATUS_FIFO_CNT(bytes);
+	bytes = bytes  & 0xFFFC; /* io in multiple of 4 bytes */
+	if (info->iomode == OMAP_NAND_IO_WRITE) { /* checks for write io */
+		if (this_irq == info->gpmc_irq_count)
+			goto done;
+
+		if (info->buf_len && (info->buf_len < bytes))
+			bytes = info->buf_len;
+		else if (!info->buf_len)
+			bytes = 0;
+		iowrite32_rep(info->nand.IO_ADDR_W,
+						(u32 *)info->buf, bytes >> 2);
+		info->buf = info->buf + bytes;
+		info->buf_len -= bytes;
+
+	} else {
+		ioread32_rep(info->nand.IO_ADDR_R,
+						(u32 *)info->buf, bytes >> 2);
+		info->buf = info->buf + bytes;
+
+		if (this_irq == info->gpmc_irq_count)
+			goto done;
+	}
+
+	return IRQ_HANDLED;
+
+done:
+	complete(&info->comp);
+
+	disable_irq_nosync(info->gpmc_irq_fifo);
+	disable_irq_nosync(info->gpmc_irq_count);
+
+	return IRQ_HANDLED;
+}
+
+/*
+ * omap_read_buf_irq_pref - read data from NAND controller into buffer
+ * @mtd: MTD device structure
+ * @buf: buffer to store date
+ * @len: number of bytes to read
+ */
+static void omap_read_buf_irq_pref(struct mtd_info *mtd, u_char *buf, int len)
+{
+	struct omap_nand_info *info = container_of(mtd,
+						struct omap_nand_info, mtd);
+	int ret = 0;
+
+	if (len <= mtd->oobsize) {
+		omap_read_buf_pref(mtd, buf, len);
+		return;
+	}
+
+	info->iomode = OMAP_NAND_IO_READ;
+	info->buf = buf;
+	init_completion(&info->comp);
+
+	/*  configure and start prefetch transfer */
+	ret = omap_prefetch_enable(info->gpmc_cs,
+			PREFETCH_FIFOTHRESHOLD_MAX/2, 0x0, len, 0x0, info);
+	if (ret)
+		/* PFPW engine is busy, use cpu copy method */
+		goto out_copy;
+
+	info->buf_len = len;
+
+	enable_irq(info->gpmc_irq_count);
+	enable_irq(info->gpmc_irq_fifo);
+
+	/* waiting for read to complete */
+	wait_for_completion(&info->comp);
+
+	/* disable and stop the PFPW engine */
+	omap_prefetch_reset(info->gpmc_cs, info);
+	return;
+
+out_copy:
+	if (info->nand.options & NAND_BUSWIDTH_16)
+		omap_read_buf16(mtd, buf, len);
+	else
+		omap_read_buf8(mtd, buf, len);
+}
+
+/*
+ * omap_write_buf_irq_pref - write buffer to NAND controller
+ * @mtd: MTD device structure
+ * @buf: data buffer
+ * @len: number of bytes to write
+ */
+static void omap_write_buf_irq_pref(struct mtd_info *mtd,
+					const u_char *buf, int len)
+{
+	struct omap_nand_info *info = container_of(mtd,
+						struct omap_nand_info, mtd);
+	int ret = 0;
+	unsigned long tim, limit;
+	u32 val;
+
+	if (len <= mtd->oobsize) {
+		omap_write_buf_pref(mtd, buf, len);
+		return;
+	}
+
+	info->iomode = OMAP_NAND_IO_WRITE;
+	info->buf = (u_char *) buf;
+	init_completion(&info->comp);
+
+	/* configure and start prefetch transfer : size=24 */
+	ret = omap_prefetch_enable(info->gpmc_cs,
+		(PREFETCH_FIFOTHRESHOLD_MAX * 3) / 8, 0x0, len, 0x1, info);
+	if (ret)
+		/* PFPW engine is busy, use cpu copy method */
+		goto out_copy;
+
+	info->buf_len = len;
+
+	enable_irq(info->gpmc_irq_count);
+	enable_irq(info->gpmc_irq_fifo);
+
+	/* waiting for write to complete */
+	wait_for_completion(&info->comp);
+
+	/* wait for data to flushed-out before reset the prefetch */
+	tim = 0;
+	limit = (loops_per_jiffy *  msecs_to_jiffies(OMAP_NAND_TIMEOUT_MS));
+	do {
+		val = readl(info->reg.gpmc_prefetch_status);
+		val = PREFETCH_STATUS_COUNT(val);
+		cpu_relax();
+	} while (val && (tim++ < limit));
+
+	/* disable and stop the PFPW engine */
+	omap_prefetch_reset(info->gpmc_cs, info);
+	return;
+
+out_copy:
+	if (info->nand.options & NAND_BUSWIDTH_16)
+		omap_write_buf16(mtd, buf, len);
+	else
+		omap_write_buf8(mtd, buf, len);
+}
+
+/**
+ * gen_true_ecc - This function will generate true ECC value
+ * @ecc_buf: buffer to store ecc code
+ *
+ * This generated true ECC value can be used when correcting
+ * data read from NAND flash memory core
+ */
+static void gen_true_ecc(u8 *ecc_buf)
+{
+	u32 tmp = ecc_buf[0] | (ecc_buf[1] << 16) |
+		((ecc_buf[2] & 0xF0) << 20) | ((ecc_buf[2] & 0x0F) << 8);
+
+	ecc_buf[0] = ~(P64o(tmp) | P64e(tmp) | P32o(tmp) | P32e(tmp) |
+			P16o(tmp) | P16e(tmp) | P8o(tmp) | P8e(tmp));
+	ecc_buf[1] = ~(P1024o(tmp) | P1024e(tmp) | P512o(tmp) | P512e(tmp) |
+			P256o(tmp) | P256e(tmp) | P128o(tmp) | P128e(tmp));
+	ecc_buf[2] = ~(P4o(tmp) | P4e(tmp) | P2o(tmp) | P2e(tmp) | P1o(tmp) |
+			P1e(tmp) | P2048o(tmp) | P2048e(tmp));
+}
+
+/**
+ * omap_compare_ecc - Detect (2 bits) and correct (1 bit) error in data
+ * @ecc_data1:  ecc code from nand spare area
+ * @ecc_data2:  ecc code from hardware register obtained from hardware ecc
+ * @page_data:  page data
+ *
+ * This function compares two ECC's and indicates if there is an error.
+ * If the error can be corrected it will be corrected to the buffer.
+ * If there is no error, %0 is returned. If there is an error but it
+ * was corrected, %1 is returned. Otherwise, %-1 is returned.
+ */
+static int omap_compare_ecc(u8 *ecc_data1,	/* read from NAND memory */
+			    u8 *ecc_data2,	/* read from register */
+			    u8 *page_data)
+{
+	uint	i;
+	u8	tmp0_bit[8], tmp1_bit[8], tmp2_bit[8];
+	u8	comp0_bit[8], comp1_bit[8], comp2_bit[8];
+	u8	ecc_bit[24];
+	u8	ecc_sum = 0;
+	u8	find_bit = 0;
+	uint	find_byte = 0;
+	int	isEccFF;
+
+	isEccFF = ((*(u32 *)ecc_data1 & 0xFFFFFF) == 0xFFFFFF);
+
+	gen_true_ecc(ecc_data1);
+	gen_true_ecc(ecc_data2);
+
+	for (i = 0; i <= 2; i++) {
+		*(ecc_data1 + i) = ~(*(ecc_data1 + i));
+		*(ecc_data2 + i) = ~(*(ecc_data2 + i));
+	}
+
+	for (i = 0; i < 8; i++) {
+		tmp0_bit[i]     = *ecc_data1 % 2;
+		*ecc_data1	= *ecc_data1 / 2;
+	}
+
+	for (i = 0; i < 8; i++) {
+		tmp1_bit[i]	 = *(ecc_data1 + 1) % 2;
+		*(ecc_data1 + 1) = *(ecc_data1 + 1) / 2;
+	}
+
+	for (i = 0; i < 8; i++) {
+		tmp2_bit[i]	 = *(ecc_data1 + 2) % 2;
+		*(ecc_data1 + 2) = *(ecc_data1 + 2) / 2;
+	}
+
+	for (i = 0; i < 8; i++) {
+		comp0_bit[i]     = *ecc_data2 % 2;
+		*ecc_data2       = *ecc_data2 / 2;
+	}
+
+	for (i = 0; i < 8; i++) {
+		comp1_bit[i]     = *(ecc_data2 + 1) % 2;
+		*(ecc_data2 + 1) = *(ecc_data2 + 1) / 2;
+	}
+
+	for (i = 0; i < 8; i++) {
+		comp2_bit[i]     = *(ecc_data2 + 2) % 2;
+		*(ecc_data2 + 2) = *(ecc_data2 + 2) / 2;
+	}
+
+	for (i = 0; i < 6; i++)
+		ecc_bit[i] = tmp2_bit[i + 2] ^ comp2_bit[i + 2];
+
+	for (i = 0; i < 8; i++)
+		ecc_bit[i + 6] = tmp0_bit[i] ^ comp0_bit[i];
+
+	for (i = 0; i < 8; i++)
+		ecc_bit[i + 14] = tmp1_bit[i] ^ comp1_bit[i];
+
+	ecc_bit[22] = tmp2_bit[0] ^ comp2_bit[0];
+	ecc_bit[23] = tmp2_bit[1] ^ comp2_bit[1];
+
+	for (i = 0; i < 24; i++)
+		ecc_sum += ecc_bit[i];
+
+	switch (ecc_sum) {
+	case 0:
+		/* Not reached because this function is not called if
+		 *  ECC values are equal
+		 */
+		return 0;
+
+	case 1:
+		/* Uncorrectable error */
+		pr_debug("ECC UNCORRECTED_ERROR 1\n");
+		return -1;
+
+	case 11:
+		/* UN-Correctable error */
+		pr_debug("ECC UNCORRECTED_ERROR B\n");
+		return -1;
+
+	case 12:
+		/* Correctable error */
+		find_byte = (ecc_bit[23] << 8) +
+			    (ecc_bit[21] << 7) +
+			    (ecc_bit[19] << 6) +
+			    (ecc_bit[17] << 5) +
+			    (ecc_bit[15] << 4) +
+			    (ecc_bit[13] << 3) +
+			    (ecc_bit[11] << 2) +
+			    (ecc_bit[9]  << 1) +
+			    ecc_bit[7];
+
+		find_bit = (ecc_bit[5] << 2) + (ecc_bit[3] << 1) + ecc_bit[1];
+
+		pr_debug("Correcting single bit ECC error at offset: "
+				"%d, bit: %d\n", find_byte, find_bit);
+
+		page_data[find_byte] ^= (1 << find_bit);
+
+		return 1;
+	default:
+		if (isEccFF) {
+			if (ecc_data2[0] == 0 &&
+			    ecc_data2[1] == 0 &&
+			    ecc_data2[2] == 0)
+				return 0;
+		}
+		pr_debug("UNCORRECTED_ERROR default\n");
+		return -1;
+	}
+}
+
+/**
+ * omap_correct_data - Compares the ECC read with HW generated ECC
+ * @mtd: MTD device structure
+ * @dat: page data
+ * @read_ecc: ecc read from nand flash
+ * @calc_ecc: ecc read from HW ECC registers
+ *
+ * Compares the ecc read from nand spare area with ECC registers values
+ * and if ECC's mismatched, it will call 'omap_compare_ecc' for error
+ * detection and correction. If there are no errors, %0 is returned. If
+ * there were errors and all of the errors were corrected, the number of
+ * corrected errors is returned. If uncorrectable errors exist, %-1 is
+ * returned.
+ */
+static int omap_correct_data(struct mtd_info *mtd, u_char *dat,
+				u_char *read_ecc, u_char *calc_ecc)
+{
+	struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
+							mtd);
+	int blockCnt = 0, i = 0, ret = 0;
+	int stat = 0;
+
+	/* Ex NAND_ECC_HW12_2048 */
+	if ((info->nand.ecc.mode == NAND_ECC_HW) &&
+			(info->nand.ecc.size  == 2048))
+		blockCnt = 4;
+	else
+		blockCnt = 1;
+
+	for (i = 0; i < blockCnt; i++) {
+		if (memcmp(read_ecc, calc_ecc, 3) != 0) {
+			ret = omap_compare_ecc(read_ecc, calc_ecc, dat);
+			if (ret < 0)
+				return ret;
+			/* keep track of the number of corrected errors */
+			stat += ret;
+		}
+		read_ecc += 3;
+		calc_ecc += 3;
+		dat      += 512;
+	}
+	return stat;
+}
+
+/**
+ * omap_calcuate_ecc - Generate non-inverted ECC bytes.
+ * @mtd: MTD device structure
+ * @dat: The pointer to data on which ecc is computed
+ * @ecc_code: The ecc_code buffer
+ *
+ * Using noninverted ECC can be considered ugly since writing a blank
+ * page ie. padding will clear the ECC bytes. This is no problem as long
+ * nobody is trying to write data on the seemingly unused page. Reading
+ * an erased page will produce an ECC mismatch between generated and read
+ * ECC bytes that has to be dealt with separately.
+ */
+static int omap_calculate_ecc(struct mtd_info *mtd, const u_char *dat,
+				u_char *ecc_code)
+{
+	struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
+							mtd);
+	u32 val;
+
+	val = readl(info->reg.gpmc_ecc_config);
+	if (((val >> ECC_CONFIG_CS_SHIFT) & CS_MASK) != info->gpmc_cs)
+		return -EINVAL;
+
+	/* read ecc result */
+	val = readl(info->reg.gpmc_ecc1_result);
+	*ecc_code++ = val;          /* P128e, ..., P1e */
+	*ecc_code++ = val >> 16;    /* P128o, ..., P1o */
+	/* P2048o, P1024o, P512o, P256o, P2048e, P1024e, P512e, P256e */
+	*ecc_code++ = ((val >> 8) & 0x0f) | ((val >> 20) & 0xf0);
+
+	return 0;
+}
+
+/**
+ * omap_enable_hwecc - This function enables the hardware ecc functionality
+ * @mtd: MTD device structure
+ * @mode: Read/Write mode
+ */
+static void omap_enable_hwecc(struct mtd_info *mtd, int mode)
+{
+	struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
+							mtd);
+	struct nand_chip *chip = mtd->priv;
+	unsigned int dev_width = (chip->options & NAND_BUSWIDTH_16) ? 1 : 0;
+	u32 val;
+
+	/* clear ecc and enable bits */
+	val = ECCCLEAR | ECC1;
+	writel(val, info->reg.gpmc_ecc_control);
+
+	/* program ecc and result sizes */
+	val = ((((info->nand.ecc.size >> 1) - 1) << ECCSIZE1_SHIFT) |
+			 ECC1RESULTSIZE);
+	writel(val, info->reg.gpmc_ecc_size_config);
+
+	switch (mode) {
+	case NAND_ECC_READ:
+	case NAND_ECC_WRITE:
+		writel(ECCCLEAR | ECC1, info->reg.gpmc_ecc_control);
+		break;
+	case NAND_ECC_READSYN:
+		writel(ECCCLEAR, info->reg.gpmc_ecc_control);
+		break;
+	default:
+		dev_info(&info->pdev->dev,
+			"error: unrecognized Mode[%d]!\n", mode);
+		break;
+	}
+
+	/* (ECC 16 or 8 bit col) | ( CS  )  | ECC Enable */
+	val = (dev_width << 7) | (info->gpmc_cs << 1) | (0x1);
+	writel(val, info->reg.gpmc_ecc_config);
+}
+
+/**
+ * omap_wait - wait until the command is done
+ * @mtd: MTD device structure
+ * @chip: NAND Chip structure
+ *
+ * Wait function is called during Program and erase operations and
+ * the way it is called from MTD layer, we should wait till the NAND
+ * chip is ready after the programming/erase operation has completed.
+ *
+ * Erase can take up to 400ms and program up to 20ms according to
+ * general NAND and SmartMedia specs
+ */
+static int omap_wait(struct mtd_info *mtd, struct nand_chip *chip)
+{
+	struct nand_chip *this = mtd->priv;
+	struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
+							mtd);
+	unsigned long timeo = jiffies;
+	int status, state = this->state;
+
+	if (state == FL_ERASING)
+		timeo += msecs_to_jiffies(400);
+	else
+		timeo += msecs_to_jiffies(20);
+
+	writeb(NAND_CMD_STATUS & 0xFF, info->reg.gpmc_nand_command);
+	while (time_before(jiffies, timeo)) {
+		status = readb(info->reg.gpmc_nand_data);
+		if (status & NAND_STATUS_READY)
+			break;
+		cond_resched();
+	}
+
+	status = readb(info->reg.gpmc_nand_data);
+	return status;
+}
+
+/**
+ * omap_dev_ready - calls the platform specific dev_ready function
+ * @mtd: MTD device structure
+ */
+static int omap_dev_ready(struct mtd_info *mtd)
+{
+	unsigned int val = 0;
+	struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
+							mtd);
+
+	val = readl(info->reg.gpmc_status);
+
+	if ((val & 0x100) == 0x100) {
+		return 1;
+	} else {
+		return 0;
+	}
+}
+
+#ifdef CONFIG_MTD_NAND_OMAP_BCH
+
+/**
+ * omap3_enable_hwecc_bch - Program OMAP3 GPMC to perform BCH ECC correction
+ * @mtd: MTD device structure
+ * @mode: Read/Write mode
+ *
+ * When using BCH, sector size is hardcoded to 512 bytes.
+ * Using wrapping mode 6 both for reading and writing if ELM module not uses
+ * for error correction.
+ * On writing,
+ * eccsize0 = 0  (no additional protected byte in spare area)
+ * eccsize1 = 32 (skip 32 nibbles = 16 bytes per sector in spare area)
+ */
+static void omap3_enable_hwecc_bch(struct mtd_info *mtd, int mode)
+{
+	int nerrors;
+	unsigned int dev_width, nsectors;
+	struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
+						   mtd);
+	struct nand_chip *chip = mtd->priv;
+	u32 val, wr_mode;
+	unsigned int ecc_size1, ecc_size0;
+
+	/* Using wrapping mode 6 for writing */
+	wr_mode = BCH_WRAPMODE_6;
+
+	/*
+	 * ECC engine enabled for valid ecc_size0 nibbles
+	 * and disabled for ecc_size1 nibbles.
+	 */
+	ecc_size0 = BCH_ECC_SIZE0;
+	ecc_size1 = BCH_ECC_SIZE1;
+
+	/* Perform ecc calculation on 512-byte sector */
+	nsectors = 1;
+
+	/* Update number of error correction */
+	nerrors = info->nand.ecc.strength;
+
+	/* Multi sector reading/writing for NAND flash with page size < 4096 */
+	if (info->is_elm_used && (mtd->writesize <= 4096)) {
+		if (mode == NAND_ECC_READ) {
+			/* Using wrapping mode 1 for reading */
+			wr_mode = BCH_WRAPMODE_1;
+
+			/*
+			 * ECC engine enabled for ecc_size0 nibbles
+			 * and disabled for ecc_size1 nibbles.
+			 */
+			ecc_size0 = (nerrors == 8) ?
+				BCH8R_ECC_SIZE0 : BCH4R_ECC_SIZE0;
+			ecc_size1 = (nerrors == 8) ?
+				BCH8R_ECC_SIZE1 : BCH4R_ECC_SIZE1;
+		}
+
+		/* Perform ecc calculation for one page (< 4096) */
+		nsectors = info->nand.ecc.steps;
+	}
+
+	writel(ECC1, info->reg.gpmc_ecc_control);
+
+	/* Configure ecc size for BCH */
+	val = (ecc_size1 << ECCSIZE1_SHIFT) | (ecc_size0 << ECCSIZE0_SHIFT);
+	writel(val, info->reg.gpmc_ecc_size_config);
+
+	dev_width = (chip->options & NAND_BUSWIDTH_16) ? 1 : 0;
+
+	/* BCH configuration */
+	val = ((1                        << 16) | /* enable BCH */
+	       (((nerrors == 8) ? 1 : 0) << 12) | /* 8 or 4 bits */
+	       (wr_mode                  <<  8) | /* wrap mode */
+	       (dev_width                <<  7) | /* bus width */
+	       (((nsectors-1) & 0x7)     <<  4) | /* number of sectors */
+	       (info->gpmc_cs            <<  1) | /* ECC CS */
+	       (0x1));                            /* enable ECC */
+
+	writel(val, info->reg.gpmc_ecc_config);
+
+	/* Clear ecc and enable bits */
+	writel(ECCCLEAR | ECC1, info->reg.gpmc_ecc_control);
+}
+
+/**
+ * omap3_calculate_ecc_bch4 - Generate 7 bytes of ECC bytes
+ * @mtd: MTD device structure
+ * @dat: The pointer to data on which ecc is computed
+ * @ecc_code: The ecc_code buffer
+ */
+static int omap3_calculate_ecc_bch4(struct mtd_info *mtd, const u_char *dat,
+				    u_char *ecc_code)
+{
+	struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
+						   mtd);
+	unsigned long nsectors, val1, val2;
+	int i;
+
+	nsectors = ((readl(info->reg.gpmc_ecc_config) >> 4) & 0x7) + 1;
+
+	for (i = 0; i < nsectors; i++) {
+
+		/* Read hw-computed remainder */
+		val1 = readl(info->reg.gpmc_bch_result0[i]);
+		val2 = readl(info->reg.gpmc_bch_result1[i]);
+
+		/*
+		 * Add constant polynomial to remainder, in order to get an ecc
+		 * sequence of 0xFFs for a buffer filled with 0xFFs; and
+		 * left-justify the resulting polynomial.
+		 */
+		*ecc_code++ = 0x28 ^ ((val2 >> 12) & 0xFF);
+		*ecc_code++ = 0x13 ^ ((val2 >>  4) & 0xFF);
+		*ecc_code++ = 0xcc ^ (((val2 & 0xF) << 4)|((val1 >> 28) & 0xF));
+		*ecc_code++ = 0x39 ^ ((val1 >> 20) & 0xFF);
+		*ecc_code++ = 0x96 ^ ((val1 >> 12) & 0xFF);
+		*ecc_code++ = 0xac ^ ((val1 >> 4) & 0xFF);
+		*ecc_code++ = 0x7f ^ ((val1 & 0xF) << 4);
+	}
+
+	return 0;
+}
+
+/**
+ * omap3_calculate_ecc_bch8 - Generate 13 bytes of ECC bytes
+ * @mtd: MTD device structure
+ * @dat: The pointer to data on which ecc is computed
+ * @ecc_code: The ecc_code buffer
+ */
+static int omap3_calculate_ecc_bch8(struct mtd_info *mtd, const u_char *dat,
+				    u_char *ecc_code)
+{
+	struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
+						   mtd);
+	unsigned long nsectors, val1, val2, val3, val4;
+	int i;
+
+	nsectors = ((readl(info->reg.gpmc_ecc_config) >> 4) & 0x7) + 1;
+
+	for (i = 0; i < nsectors; i++) {
+
+		/* Read hw-computed remainder */
+		val1 = readl(info->reg.gpmc_bch_result0[i]);
+		val2 = readl(info->reg.gpmc_bch_result1[i]);
+		val3 = readl(info->reg.gpmc_bch_result2[i]);
+		val4 = readl(info->reg.gpmc_bch_result3[i]);
+
+		/*
+		 * Add constant polynomial to remainder, in order to get an ecc
+		 * sequence of 0xFFs for a buffer filled with 0xFFs.
+		 */
+		*ecc_code++ = 0xef ^ (val4 & 0xFF);
+		*ecc_code++ = 0x51 ^ ((val3 >> 24) & 0xFF);
+		*ecc_code++ = 0x2e ^ ((val3 >> 16) & 0xFF);
+		*ecc_code++ = 0x09 ^ ((val3 >> 8) & 0xFF);
+		*ecc_code++ = 0xed ^ (val3 & 0xFF);
+		*ecc_code++ = 0x93 ^ ((val2 >> 24) & 0xFF);
+		*ecc_code++ = 0x9a ^ ((val2 >> 16) & 0xFF);
+		*ecc_code++ = 0xc2 ^ ((val2 >> 8) & 0xFF);
+		*ecc_code++ = 0x97 ^ (val2 & 0xFF);
+		*ecc_code++ = 0x79 ^ ((val1 >> 24) & 0xFF);
+		*ecc_code++ = 0xe5 ^ ((val1 >> 16) & 0xFF);
+		*ecc_code++ = 0x24 ^ ((val1 >> 8) & 0xFF);
+		*ecc_code++ = 0xb5 ^ (val1 & 0xFF);
+	}
+
+	return 0;
+}
+
+/**
+ * omap3_calculate_ecc_bch - Generate bytes of ECC bytes
+ * @mtd:	MTD device structure
+ * @dat:	The pointer to data on which ecc is computed
+ * @ecc_code:	The ecc_code buffer
+ *
+ * Support calculating of BCH4/8 ecc vectors for the page
+ */
+static int omap3_calculate_ecc_bch(struct mtd_info *mtd, const u_char *dat,
+				    u_char *ecc_code)
+{
+	struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
+						   mtd);
+	unsigned long nsectors, bch_val1, bch_val2, bch_val3, bch_val4;
+	int i, eccbchtsel;
+
+	nsectors = ((readl(info->reg.gpmc_ecc_config) >> 4) & 0x7) + 1;
+	/*
+	 * find BCH scheme used
+	 * 0 -> BCH4
+	 * 1 -> BCH8
+	 */
+	eccbchtsel = ((readl(info->reg.gpmc_ecc_config) >> 12) & 0x3);
+
+	for (i = 0; i < nsectors; i++) {
+
+		/* Read hw-computed remainder */
+		bch_val1 = readl(info->reg.gpmc_bch_result0[i]);
+		bch_val2 = readl(info->reg.gpmc_bch_result1[i]);
+		if (eccbchtsel) {
+			bch_val3 = readl(info->reg.gpmc_bch_result2[i]);
+			bch_val4 = readl(info->reg.gpmc_bch_result3[i]);
+		}
+
+		if (eccbchtsel) {
+			/* BCH8 ecc scheme */
+			*ecc_code++ = (bch_val4 & 0xFF);
+			*ecc_code++ = ((bch_val3 >> 24) & 0xFF);
+			*ecc_code++ = ((bch_val3 >> 16) & 0xFF);
+			*ecc_code++ = ((bch_val3 >> 8) & 0xFF);
+			*ecc_code++ = (bch_val3 & 0xFF);
+			*ecc_code++ = ((bch_val2 >> 24) & 0xFF);
+			*ecc_code++ = ((bch_val2 >> 16) & 0xFF);
+			*ecc_code++ = ((bch_val2 >> 8) & 0xFF);
+			*ecc_code++ = (bch_val2 & 0xFF);
+			*ecc_code++ = ((bch_val1 >> 24) & 0xFF);
+			*ecc_code++ = ((bch_val1 >> 16) & 0xFF);
+			*ecc_code++ = ((bch_val1 >> 8) & 0xFF);
+			*ecc_code++ = (bch_val1 & 0xFF);
+			/*
+			 * Setting 14th byte to zero to handle
+			 * erased page & maintain compatibility
+			 * with RBL
+			 */
+			*ecc_code++ = 0x0;
+		} else {
+			/* BCH4 ecc scheme */
+			*ecc_code++ = ((bch_val2 >> 12) & 0xFF);
+			*ecc_code++ = ((bch_val2 >> 4) & 0xFF);
+			*ecc_code++ = ((bch_val2 & 0xF) << 4) |
+				((bch_val1 >> 28) & 0xF);
+			*ecc_code++ = ((bch_val1 >> 20) & 0xFF);
+			*ecc_code++ = ((bch_val1 >> 12) & 0xFF);
+			*ecc_code++ = ((bch_val1 >> 4) & 0xFF);
+			*ecc_code++ = ((bch_val1 & 0xF) << 4);
+			/*
+			 * Setting 8th byte to zero to handle
+			 * erased page
+			 */
+			*ecc_code++ = 0x0;
+		}
+	}
+
+	return 0;
+}
+
+/**
+ * erased_sector_bitflips - count bit flips
+ * @data:	data sector buffer
+ * @oob:	oob buffer
+ * @info:	omap_nand_info
+ *
+ * Check the bit flips in erased page falls below correctable level.
+ * If falls below, report the page as erased with correctable bit
+ * flip, else report as uncorrectable page.
+ */
+static int erased_sector_bitflips(u_char *data, u_char *oob,
+		struct omap_nand_info *info)
+{
+	int flip_bits = 0, i;
+
+	for (i = 0; i < info->nand.ecc.size; i++) {
+		flip_bits += hweight8(~data[i]);
+		if (flip_bits > info->nand.ecc.strength)
+			return 0;
+	}
+
+	for (i = 0; i < info->nand.ecc.bytes - 1; i++) {
+		flip_bits += hweight8(~oob[i]);
+		if (flip_bits > info->nand.ecc.strength)
+			return 0;
+	}
+
+	/*
+	 * Bit flips falls in correctable level.
+	 * Fill data area with 0xFF
+	 */
+	if (flip_bits) {
+		memset(data, 0xFF, info->nand.ecc.size);
+		memset(oob, 0xFF, info->nand.ecc.bytes);
+	}
+
+	return flip_bits;
+}
+
+/**
+ * omap_elm_correct_data - corrects page data area in case error reported
+ * @mtd:	MTD device structure
+ * @data:	page data
+ * @read_ecc:	ecc read from nand flash
+ * @calc_ecc:	ecc read from HW ECC registers
+ *
+ * Calculated ecc vector reported as zero in case of non-error pages.
+ * In case of error/erased pages non-zero error vector is reported.
+ * In case of non-zero ecc vector, check read_ecc at fixed offset
+ * (x = 13/7 in case of BCH8/4 == 0) to find page programmed or not.
+ * To handle bit flips in this data, count the number of 0's in
+ * read_ecc[x] and check if it greater than 4. If it is less, it is
+ * programmed page, else erased page.
+ *
+ * 1. If page is erased, check with standard ecc vector (ecc vector
+ * for erased page to find any bit flip). If check fails, bit flip
+ * is present in erased page. Count the bit flips in erased page and
+ * if it falls under correctable level, report page with 0xFF and
+ * update the correctable bit information.
+ * 2. If error is reported on programmed page, update elm error
+ * vector and correct the page with ELM error correction routine.
+ *
+ */
+static int omap_elm_correct_data(struct mtd_info *mtd, u_char *data,
+				u_char *read_ecc, u_char *calc_ecc)
+{
+	struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
+			mtd);
+	int eccsteps = info->nand.ecc.steps;
+	int i , j, stat = 0;
+	int eccsize, eccflag, ecc_vector_size;
+	struct elm_errorvec err_vec[ERROR_VECTOR_MAX];
+	u_char *ecc_vec = calc_ecc;
+	u_char *spare_ecc = read_ecc;
+	u_char *erased_ecc_vec;
+	enum bch_ecc type;
+	bool is_error_reported = false;
+
+	/* Initialize elm error vector to zero */
+	memset(err_vec, 0, sizeof(err_vec));
+
+	if (info->nand.ecc.strength == BCH8_MAX_ERROR) {
+		type = BCH8_ECC;
+		erased_ecc_vec = bch8_vector;
+	} else {
+		type = BCH4_ECC;
+		erased_ecc_vec = bch4_vector;
+	}
+
+	ecc_vector_size = info->nand.ecc.bytes;
+
+	/*
+	 * Remove extra byte padding for BCH8 RBL
+	 * compatibility and erased page handling
+	 */
+	eccsize = ecc_vector_size - 1;
+
+	for (i = 0; i < eccsteps ; i++) {
+		eccflag = 0;	/* initialize eccflag */
+
+		/*
+		 * Check any error reported,
+		 * In case of error, non zero ecc reported.
+		 */
+
+		for (j = 0; (j < eccsize); j++) {
+			if (calc_ecc[j] != 0) {
+				eccflag = 1; /* non zero ecc, error present */
+				break;
+			}
+		}
+
+		if (eccflag == 1) {
+			/*
+			 * Set threshold to minimum of 4, half of ecc.strength/2
+			 * to allow max bit flip in byte to 4
+			 */
+			unsigned int threshold = min_t(unsigned int, 4,
+					info->nand.ecc.strength / 2);
+
+			/*
+			 * Check data area is programmed by counting
+			 * number of 0's at fixed offset in spare area.
+			 * Checking count of 0's against threshold.
+			 * In case programmed page expects at least threshold
+			 * zeros in byte.
+			 * If zeros are less than threshold for programmed page/
+			 * zeros are more than threshold erased page, either
+			 * case page reported as uncorrectable.
+			 */
+			if (hweight8(~read_ecc[eccsize]) >= threshold) {
+				/*
+				 * Update elm error vector as
+				 * data area is programmed
+				 */
+				err_vec[i].error_reported = true;
+				is_error_reported = true;
+			} else {
+				/* Error reported in erased page */
+				int bitflip_count;
+				u_char *buf = &data[info->nand.ecc.size * i];
+
+				if (memcmp(calc_ecc, erased_ecc_vec, eccsize)) {
+					bitflip_count = erased_sector_bitflips(
+							buf, read_ecc, info);
+
+					if (bitflip_count)
+						stat += bitflip_count;
+					else
+						return -EINVAL;
+				}
+			}
+		}
+
+		/* Update the ecc vector */
+		calc_ecc += ecc_vector_size;
+		read_ecc += ecc_vector_size;
+	}
+
+	/* Check if any error reported */
+	if (!is_error_reported)
+		return stat;
+
+	/* Decode BCH error using ELM module */
+	elm_decode_bch_error_page(info->elm_dev, ecc_vec, err_vec);
+
+	for (i = 0; i < eccsteps; i++) {
+		if (err_vec[i].error_reported) {
+			for (j = 0; j < err_vec[i].error_count; j++) {
+				u32 bit_pos, byte_pos, error_max, pos;
+
+				if (type == BCH8_ECC)
+					error_max = BCH8_ECC_MAX;
+				else
+					error_max = BCH4_ECC_MAX;
+
+				if (info->nand.ecc.strength == BCH8_MAX_ERROR)
+					pos = err_vec[i].error_loc[j];
+				else
+					/* Add 4 to take care 4 bit padding */
+					pos = err_vec[i].error_loc[j] +
+						BCH4_BIT_PAD;
+
+				/* Calculate bit position of error */
+				bit_pos = pos % 8;
+
+				/* Calculate byte position of error */
+				byte_pos = (error_max - pos - 1) / 8;
+
+				if (pos < error_max) {
+					if (byte_pos < 512)
+						data[byte_pos] ^= 1 << bit_pos;
+					else
+						spare_ecc[byte_pos - 512] ^=
+							1 << bit_pos;
+				}
+				/* else, not interested to correct ecc */
+			}
+		}
+
+		/* Update number of correctable errors */
+		stat += err_vec[i].error_count;
+
+		/* Update page data with sector size */
+		data += info->nand.ecc.size;
+		spare_ecc += ecc_vector_size;
+	}
+
+	for (i = 0; i < eccsteps; i++)
+		/* Return error if uncorrectable error present */
+		if (err_vec[i].error_uncorrectable)
+			return -EINVAL;
+
+	return stat;
+}
+
+/**
+ * omap3_correct_data_bch - Decode received data and correct errors
+ * @mtd: MTD device structure
+ * @data: page data
+ * @read_ecc: ecc read from nand flash
+ * @calc_ecc: ecc read from HW ECC registers
+ */
+static int omap3_correct_data_bch(struct mtd_info *mtd, u_char *data,
+				  u_char *read_ecc, u_char *calc_ecc)
+{
+	int i, count;
+	/* cannot correct more than 8 errors */
+	unsigned int errloc[8];
+	struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
+						   mtd);
+
+	count = decode_bch(info->bch, NULL, 512, read_ecc, calc_ecc, NULL,
+			   errloc);
+	if (count > 0) {
+		/* correct errors */
+		for (i = 0; i < count; i++) {
+			/* correct data only, not ecc bytes */
+			if (errloc[i] < 8*512)
+				data[errloc[i]/8] ^= 1 << (errloc[i] & 7);
+			pr_debug("corrected bitflip %u\n", errloc[i]);
+		}
+	} else if (count < 0) {
+		pr_err("ecc unrecoverable error\n");
+	}
+	return count;
+}
+
+/**
+ * omap_write_page_bch - BCH ecc based write page function for entire page
+ * @mtd:		mtd info structure
+ * @chip:		nand chip info structure
+ * @buf:		data buffer
+ * @oob_required:	must write chip->oob_poi to OOB
+ *
+ * Custom write page method evolved to support multi sector writing in one shot
+ */
+static int omap_write_page_bch(struct mtd_info *mtd, struct nand_chip *chip,
+				  const uint8_t *buf, int oob_required)
+{
+	int i;
+	uint8_t *ecc_calc = chip->buffers->ecccalc;
+	uint32_t *eccpos = chip->ecc.layout->eccpos;
+
+	/* Enable GPMC ecc engine */
+	chip->ecc.hwctl(mtd, NAND_ECC_WRITE);
+
+	/* Write data */
+	chip->write_buf(mtd, buf, mtd->writesize);
+
+	/* Update ecc vector from GPMC result registers */
+	chip->ecc.calculate(mtd, buf, &ecc_calc[0]);
+
+	for (i = 0; i < chip->ecc.total; i++)
+		chip->oob_poi[eccpos[i]] = ecc_calc[i];
+
+	/* Write ecc vector to OOB area */
+	chip->write_buf(mtd, chip->oob_poi, mtd->oobsize);
+	return 0;
+}
+
+/**
+ * omap_read_page_bch - BCH ecc based page read function for entire page
+ * @mtd:		mtd info structure
+ * @chip:		nand chip info structure
+ * @buf:		buffer to store read data
+ * @oob_required:	caller requires OOB data read to chip->oob_poi
+ * @page:		page number to read
+ *
+ * For BCH ecc scheme, GPMC used for syndrome calculation and ELM module
+ * used for error correction.
+ * Custom method evolved to support ELM error correction & multi sector
+ * reading. On reading page data area is read along with OOB data with
+ * ecc engine enabled. ecc vector updated after read of OOB data.
+ * For non error pages ecc vector reported as zero.
+ */
+static int omap_read_page_bch(struct mtd_info *mtd, struct nand_chip *chip,
+				uint8_t *buf, int oob_required, int page)
+{
+	uint8_t *ecc_calc = chip->buffers->ecccalc;
+	uint8_t *ecc_code = chip->buffers->ecccode;
+	uint32_t *eccpos = chip->ecc.layout->eccpos;
+	uint8_t *oob = &chip->oob_poi[eccpos[0]];
+	uint32_t oob_pos = mtd->writesize + chip->ecc.layout->eccpos[0];
+	int stat;
+	unsigned int max_bitflips = 0;
+
+	/* Enable GPMC ecc engine */
+	chip->ecc.hwctl(mtd, NAND_ECC_READ);
+
+	/* Read data */
+	chip->read_buf(mtd, buf, mtd->writesize);
+
+	/* Read oob bytes */
+	chip->cmdfunc(mtd, NAND_CMD_RNDOUT, oob_pos, -1);
+	chip->read_buf(mtd, oob, chip->ecc.total);
+
+	/* Calculate ecc bytes */
+	chip->ecc.calculate(mtd, buf, ecc_calc);
+
+	memcpy(ecc_code, &chip->oob_poi[eccpos[0]], chip->ecc.total);
+
+	stat = chip->ecc.correct(mtd, buf, ecc_code, ecc_calc);
+
+	if (stat < 0) {
+		mtd->ecc_stats.failed++;
+	} else {
+		mtd->ecc_stats.corrected += stat;
+		max_bitflips = max_t(unsigned int, max_bitflips, stat);
+	}
+
+	return max_bitflips;
+}
+
+/**
+ * omap3_free_bch - Release BCH ecc resources
+ * @mtd: MTD device structure
+ */
+static void omap3_free_bch(struct mtd_info *mtd)
+{
+	struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
+						   mtd);
+	if (info->bch) {
+		free_bch(info->bch);
+		info->bch = NULL;
+	}
+}
+
+/**
+ * omap3_init_bch - Initialize BCH ECC
+ * @mtd: MTD device structure
+ * @ecc_opt: OMAP ECC mode (OMAP_ECC_BCH4_CODE_HW or OMAP_ECC_BCH8_CODE_HW)
+ */
+static int omap3_init_bch(struct mtd_info *mtd, int ecc_opt)
+{
+	int max_errors;
+	struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
+						   mtd);
+#ifdef CONFIG_MTD_NAND_OMAP_BCH8
+	const int hw_errors = BCH8_MAX_ERROR;
+#else
+	const int hw_errors = BCH4_MAX_ERROR;
+#endif
+	enum bch_ecc bch_type;
+	const __be32 *parp;
+	int lenp;
+	struct device_node *elm_node;
+
+	info->bch = NULL;
+
+	max_errors = (ecc_opt == OMAP_ECC_BCH8_CODE_HW) ?
+		BCH8_MAX_ERROR : BCH4_MAX_ERROR;
+	if (max_errors != hw_errors) {
+		pr_err("cannot configure %d-bit BCH ecc, only %d-bit supported",
+		       max_errors, hw_errors);
+		goto fail;
+	}
+
+	info->nand.ecc.size = 512;
+	info->nand.ecc.hwctl = omap3_enable_hwecc_bch;
+	info->nand.ecc.mode = NAND_ECC_HW;
+	info->nand.ecc.strength = max_errors;
+
+	if (hw_errors == BCH8_MAX_ERROR)
+		bch_type = BCH8_ECC;
+	else
+		bch_type = BCH4_ECC;
+
+	/* Detect availability of ELM module */
+	parp = of_get_property(info->of_node, "elm_id", &lenp);
+	if ((parp == NULL) && (lenp != (sizeof(void *) * 2))) {
+		pr_err("Missing elm_id property, fall back to Software BCH\n");
+		info->is_elm_used = false;
+	} else {
+		struct platform_device *pdev;
+
+		elm_node = of_find_node_by_phandle(be32_to_cpup(parp));
+		pdev = of_find_device_by_node(elm_node);
+		info->elm_dev = &pdev->dev;
+
+		if (elm_config(info->elm_dev, bch_type) == 0)
+			info->is_elm_used = true;
+	}
+
+	if (info->is_elm_used && (mtd->writesize <= 4096)) {
+
+		if (hw_errors == BCH8_MAX_ERROR)
+			info->nand.ecc.bytes = BCH8_SIZE;
+		else
+			info->nand.ecc.bytes = BCH4_SIZE;
+
+		info->nand.ecc.correct = omap_elm_correct_data;
+		info->nand.ecc.calculate = omap3_calculate_ecc_bch;
+		info->nand.ecc.read_page = omap_read_page_bch;
+		info->nand.ecc.write_page = omap_write_page_bch;
+	} else {
+		/*
+		 * software bch library is only used to detect and
+		 * locate errors
+		 */
+		info->bch = init_bch(13, max_errors,
+				0x201b /* hw polynomial */);
+		if (!info->bch)
+			goto fail;
+
+		info->nand.ecc.correct = omap3_correct_data_bch;
+
+		/*
+		 * The number of corrected errors in an ecc block that will
+		 * trigger block scrubbing defaults to the ecc strength (4 or 8)
+		 * Set mtd->bitflip_threshold here to define a custom threshold.
+		 */
+
+		if (max_errors == 8) {
+			info->nand.ecc.bytes = 13;
+			info->nand.ecc.calculate = omap3_calculate_ecc_bch8;
+		} else {
+			info->nand.ecc.bytes = 7;
+			info->nand.ecc.calculate = omap3_calculate_ecc_bch4;
+		}
+	}
+
+	pr_info("enabling NAND BCH ecc with %d-bit correction\n", max_errors);
+	return 0;
+fail:
+	omap3_free_bch(mtd);
+	return -1;
+}
+
+/**
+ * omap3_init_bch_tail - Build an oob layout for BCH ECC correction.
+ * @mtd: MTD device structure
+ */
+static int omap3_init_bch_tail(struct mtd_info *mtd)
+{
+	int i, steps, offset;
+	struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
+						   mtd);
+	struct nand_ecclayout *layout = &info->ecclayout;
+
+	/* build oob layout */
+	steps = mtd->writesize/info->nand.ecc.size;
+	layout->eccbytes = steps*info->nand.ecc.bytes;
+
+	/* do not bother creating special oob layouts for small page devices */
+	if (mtd->oobsize < 64) {
+		pr_err("BCH ecc is not supported on small page devices\n");
+		goto fail;
+	}
+
+	/* reserve 2 bytes for bad block marker */
+	if (layout->eccbytes+2 > mtd->oobsize) {
+		pr_err("no oob layout available for oobsize %d eccbytes %u\n",
+		       mtd->oobsize, layout->eccbytes);
+		goto fail;
+	}
+
+	/* ECC layout compatible with RBL for BCH8 */
+	if (info->is_elm_used && (info->nand.ecc.bytes == BCH8_SIZE))
+		offset = 2;
+	else
+		offset = mtd->oobsize - layout->eccbytes;
+
+	/* put ecc bytes at oob tail */
+	for (i = 0; i < layout->eccbytes; i++)
+		layout->eccpos[i] = offset + i;
+
+	if (info->is_elm_used && (info->nand.ecc.bytes == BCH8_SIZE))
+		layout->oobfree[0].offset = 2 + layout->eccbytes * steps;
+	else
+		layout->oobfree[0].offset = 2;
+
+	layout->oobfree[0].length = mtd->oobsize-2-layout->eccbytes;
+	info->nand.ecc.layout = layout;
+
+	if (!(info->nand.options & NAND_BUSWIDTH_16))
+		info->nand.badblock_pattern = &bb_descrip_flashbased;
+	return 0;
+fail:
+	omap3_free_bch(mtd);
+	return -1;
+}
+
+#else
+static int omap3_init_bch(struct mtd_info *mtd, int ecc_opt)
+{
+	pr_err("CONFIG_MTD_NAND_OMAP_BCH is not enabled\n");
+	return -1;
+}
+static int omap3_init_bch_tail(struct mtd_info *mtd)
+{
+	return -1;
+}
+static void omap3_free_bch(struct mtd_info *mtd)
+{
+}
+#endif /* CONFIG_MTD_NAND_OMAP_BCH */
+
+static int omap_nand_probe(struct platform_device *pdev)
+{
+	struct omap_nand_info		*info;
+	struct omap_nand_platform_data	*pdata;
+	int				err;
+	int				i, offset;
+	dma_cap_mask_t mask;
+	unsigned sig;
+	struct resource			*res;
+	struct mtd_part_parser_data	ppdata = {};
+
+	pdata = pdev->dev.platform_data;
+	if (pdata == NULL) {
+		dev_err(&pdev->dev, "platform data missing\n");
+		return -ENODEV;
+	}
+
+	info = kzalloc(sizeof(struct omap_nand_info), GFP_KERNEL);
+	if (!info)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, info);
+
+	spin_lock_init(&info->controller.lock);
+	init_waitqueue_head(&info->controller.wq);
+
+	info->pdev = pdev;
+
+	info->gpmc_cs		= pdata->cs;
+	info->reg		= pdata->reg;
+
+	info->mtd.priv		= &info->nand;
+	info->mtd.name		= dev_name(&pdev->dev);
+	info->mtd.owner		= THIS_MODULE;
+
+	info->nand.options	= pdata->devsize;
+	info->nand.options	|= NAND_SKIP_BBTSCAN;
+#ifdef CONFIG_MTD_NAND_OMAP_BCH
+	info->of_node		= pdata->of_node;
+#endif
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (res == NULL) {
+		err = -EINVAL;
+		dev_err(&pdev->dev, "error getting memory resource\n");
+		goto out_free_info;
+	}
+
+	info->phys_base = res->start;
+	info->mem_size = resource_size(res);
+
+	if (!request_mem_region(info->phys_base, info->mem_size,
+				pdev->dev.driver->name)) {
+		err = -EBUSY;
+		goto out_free_info;
+	}
+
+	info->nand.IO_ADDR_R = ioremap(info->phys_base, info->mem_size);
+	if (!info->nand.IO_ADDR_R) {
+		err = -ENOMEM;
+		goto out_release_mem_region;
+	}
+
+	info->nand.controller = &info->controller;
+
+	info->nand.IO_ADDR_W = info->nand.IO_ADDR_R;
+	info->nand.cmd_ctrl  = omap_hwcontrol;
+
+	/*
+	 * If RDY/BSY line is connected to OMAP then use the omap ready
+	 * function and the generic nand_wait function which reads the status
+	 * register after monitoring the RDY/BSY line. Otherwise use a standard
+	 * chip delay which is slightly more than tR (AC Timing) of the NAND
+	 * device and read status register until you get a failure or success
+	 */
+	if (pdata->dev_ready) {
+		info->nand.dev_ready = omap_dev_ready;
+		info->nand.chip_delay = 0;
+	} else {
+		info->nand.waitfunc = omap_wait;
+		info->nand.chip_delay = 50;
+	}
+
+	switch (pdata->xfer_type) {
+	case NAND_OMAP_PREFETCH_POLLED:
+		info->nand.read_buf   = omap_read_buf_pref;
+		info->nand.write_buf  = omap_write_buf_pref;
+		break;
+
+	case NAND_OMAP_POLLED:
+		if (info->nand.options & NAND_BUSWIDTH_16) {
+			info->nand.read_buf   = omap_read_buf16;
+			info->nand.write_buf  = omap_write_buf16;
+		} else {
+			info->nand.read_buf   = omap_read_buf8;
+			info->nand.write_buf  = omap_write_buf8;
+		}
+		break;
+
+	case NAND_OMAP_PREFETCH_DMA:
+		dma_cap_zero(mask);
+		dma_cap_set(DMA_SLAVE, mask);
+		sig = OMAP24XX_DMA_GPMC;
+		info->dma = dma_request_channel(mask, omap_dma_filter_fn, &sig);
+		if (!info->dma) {
+			dev_err(&pdev->dev, "DMA engine request failed\n");
+			err = -ENXIO;
+			goto out_release_mem_region;
+		} else {
+			struct dma_slave_config cfg;
+
+			memset(&cfg, 0, sizeof(cfg));
+			cfg.src_addr = info->phys_base;
+			cfg.dst_addr = info->phys_base;
+			cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+			cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+			cfg.src_maxburst = 16;
+			cfg.dst_maxburst = 16;
+			err = dmaengine_slave_config(info->dma, &cfg);
+			if (err) {
+				dev_err(&pdev->dev, "DMA engine slave config failed: %d\n",
+					err);
+				goto out_release_mem_region;
+			}
+			info->nand.read_buf   = omap_read_buf_dma_pref;
+			info->nand.write_buf  = omap_write_buf_dma_pref;
+		}
+		break;
+
+	case NAND_OMAP_PREFETCH_IRQ:
+		info->gpmc_irq_fifo = platform_get_irq(pdev, 0);
+		if (info->gpmc_irq_fifo <= 0) {
+			dev_err(&pdev->dev, "error getting fifo irq\n");
+			err = -ENODEV;
+			goto out_release_mem_region;
+		}
+		err = request_irq(info->gpmc_irq_fifo,	omap_nand_irq,
+					IRQF_SHARED, "gpmc-nand-fifo", info);
+		if (err) {
+			dev_err(&pdev->dev, "requesting irq(%d) error:%d",
+						info->gpmc_irq_fifo, err);
+			info->gpmc_irq_fifo = 0;
+			goto out_release_mem_region;
+		}
+
+		info->gpmc_irq_count = platform_get_irq(pdev, 1);
+		if (info->gpmc_irq_count <= 0) {
+			dev_err(&pdev->dev, "error getting count irq\n");
+			err = -ENODEV;
+			goto out_release_mem_region;
+		}
+		err = request_irq(info->gpmc_irq_count,	omap_nand_irq,
+					IRQF_SHARED, "gpmc-nand-count", info);
+		if (err) {
+			dev_err(&pdev->dev, "requesting irq(%d) error:%d",
+						info->gpmc_irq_count, err);
+			info->gpmc_irq_count = 0;
+			goto out_release_mem_region;
+		}
+
+		info->nand.read_buf  = omap_read_buf_irq_pref;
+		info->nand.write_buf = omap_write_buf_irq_pref;
+
+		break;
+
+	default:
+		dev_err(&pdev->dev,
+			"xfer_type(%d) not supported!\n", pdata->xfer_type);
+		err = -EINVAL;
+		goto out_release_mem_region;
+	}
+
+	/* select the ecc type */
+	if (pdata->ecc_opt == OMAP_ECC_HAMMING_CODE_DEFAULT)
+		info->nand.ecc.mode = NAND_ECC_SOFT;
+	else if ((pdata->ecc_opt == OMAP_ECC_HAMMING_CODE_HW) ||
+		(pdata->ecc_opt == OMAP_ECC_HAMMING_CODE_HW_ROMCODE)) {
+		info->nand.ecc.bytes            = 3;
+		info->nand.ecc.size             = 512;
+		info->nand.ecc.strength         = 1;
+		info->nand.ecc.calculate        = omap_calculate_ecc;
+		info->nand.ecc.hwctl            = omap_enable_hwecc;
+		info->nand.ecc.correct          = omap_correct_data;
+		info->nand.ecc.mode             = NAND_ECC_HW;
+	} else if ((pdata->ecc_opt == OMAP_ECC_BCH4_CODE_HW) ||
+		   (pdata->ecc_opt == OMAP_ECC_BCH8_CODE_HW)) {
+		err = omap3_init_bch(&info->mtd, pdata->ecc_opt);
+		if (err) {
+			err = -EINVAL;
+			goto out_release_mem_region;
+		}
+	}
+
+	/* DIP switches on some boards change between 8 and 16 bit
+	 * bus widths for flash.  Try the other width if the first try fails.
+	 */
+	if (nand_scan_ident(&info->mtd, 1, NULL)) {
+		info->nand.options ^= NAND_BUSWIDTH_16;
+		if (nand_scan_ident(&info->mtd, 1, NULL)) {
+			err = -ENXIO;
+			goto out_release_mem_region;
+		}
+	}
+
+	/* rom code layout */
+	if (pdata->ecc_opt == OMAP_ECC_HAMMING_CODE_HW_ROMCODE) {
+
+		if (info->nand.options & NAND_BUSWIDTH_16)
+			offset = 2;
+		else {
+			offset = 1;
+			info->nand.badblock_pattern = &bb_descrip_flashbased;
+		}
+		omap_oobinfo.eccbytes = 3 * (info->mtd.oobsize/16);
+		for (i = 0; i < omap_oobinfo.eccbytes; i++)
+			omap_oobinfo.eccpos[i] = i+offset;
+
+		omap_oobinfo.oobfree->offset = offset + omap_oobinfo.eccbytes;
+		omap_oobinfo.oobfree->length = info->mtd.oobsize -
+					(offset + omap_oobinfo.eccbytes);
+
+		info->nand.ecc.layout = &omap_oobinfo;
+	} else if ((pdata->ecc_opt == OMAP_ECC_BCH4_CODE_HW) ||
+		   (pdata->ecc_opt == OMAP_ECC_BCH8_CODE_HW)) {
+		/* build OOB layout for BCH ECC correction */
+		err = omap3_init_bch_tail(&info->mtd);
+		if (err) {
+			err = -EINVAL;
+			goto out_release_mem_region;
+		}
+	}
+
+	/* second phase scan */
+	if (nand_scan_tail(&info->mtd)) {
+		err = -ENXIO;
+		goto out_release_mem_region;
+	}
+
+	ppdata.of_node = pdata->of_node;
+	mtd_device_parse_register(&info->mtd, NULL, &ppdata, pdata->parts,
+				  pdata->nr_parts);
+
+	platform_set_drvdata(pdev, &info->mtd);
+
+	return 0;
+
+out_release_mem_region:
+	if (info->dma)
+		dma_release_channel(info->dma);
+	if (info->gpmc_irq_count > 0)
+		free_irq(info->gpmc_irq_count, info);
+	if (info->gpmc_irq_fifo > 0)
+		free_irq(info->gpmc_irq_fifo, info);
+	release_mem_region(info->phys_base, info->mem_size);
+out_free_info:
+	kfree(info);
+
+	return err;
+}
+
+static int omap_nand_remove(struct platform_device *pdev)
+{
+	struct mtd_info *mtd = platform_get_drvdata(pdev);
+	struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
+							mtd);
+	omap3_free_bch(&info->mtd);
+
+	platform_set_drvdata(pdev, NULL);
+	if (info->dma)
+		dma_release_channel(info->dma);
+
+	if (info->gpmc_irq_count > 0)
+		free_irq(info->gpmc_irq_count, info);
+	if (info->gpmc_irq_fifo > 0)
+		free_irq(info->gpmc_irq_fifo, info);
+
+	/* Release NAND device, its internal structures and partitions */
+	nand_release(&info->mtd);
+	iounmap(info->nand.IO_ADDR_R);
+	release_mem_region(info->phys_base, info->mem_size);
+	kfree(info);
+	return 0;
+}
+
+static struct platform_driver omap_nand_driver = {
+	.probe		= omap_nand_probe,
+	.remove		= omap_nand_remove,
+	.driver		= {
+		.name	= DRIVER_NAME,
+		.owner	= THIS_MODULE,
+	},
+};
+
+module_platform_driver(omap_nand_driver);
+
+MODULE_ALIAS("platform:" DRIVER_NAME);
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Glue layer for NAND flash on TI OMAP boards");