ASR_BASE

Change-Id: Icf3719cc0afe3eeb3edc7fa80a2eb5199ca9dda1
diff --git a/marvell/uboot/drivers/mtd/nand/atmel_nand.c b/marvell/uboot/drivers/mtd/nand/atmel_nand.c
new file mode 100644
index 0000000..05ddfbb
--- /dev/null
+++ b/marvell/uboot/drivers/mtd/nand/atmel_nand.c
@@ -0,0 +1,1229 @@
+/*
+ * (C) Copyright 2007-2008
+ * Stelian Pop <stelian@popies.net>
+ * Lead Tech Design <www.leadtechdesign.com>
+ *
+ * (C) Copyright 2006 ATMEL Rousset, Lacressonniere Nicolas
+ *
+ * Add Programmable Multibit ECC support for various AT91 SoC
+ *     (C) Copyright 2012 ATMEL, Hong Xu
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <asm/gpio.h>
+#include <asm/arch/gpio.h>
+
+#include <malloc.h>
+#include <nand.h>
+#include <watchdog.h>
+
+#ifdef CONFIG_ATMEL_NAND_HWECC
+
+/* Register access macros */
+#define ecc_readl(add, reg)				\
+	readl(AT91_BASE_SYS + add + ATMEL_ECC_##reg)
+#define ecc_writel(add, reg, value)			\
+	writel((value), AT91_BASE_SYS + add + ATMEL_ECC_##reg)
+
+#include "atmel_nand_ecc.h"	/* Hardware ECC registers */
+
+#ifdef CONFIG_ATMEL_NAND_HW_PMECC
+
+struct atmel_nand_host {
+	struct pmecc_regs __iomem *pmecc;
+	struct pmecc_errloc_regs __iomem *pmerrloc;
+	void __iomem		*pmecc_rom_base;
+
+	u8		pmecc_corr_cap;
+	u16		pmecc_sector_size;
+	u32		pmecc_index_table_offset;
+
+	int		pmecc_bytes_per_sector;
+	int		pmecc_sector_number;
+	int		pmecc_degree;	/* Degree of remainders */
+	int		pmecc_cw_len;	/* Length of codeword */
+
+	/* lookup table for alpha_to and index_of */
+	void __iomem	*pmecc_alpha_to;
+	void __iomem	*pmecc_index_of;
+
+	/* data for pmecc computation */
+	int16_t	*pmecc_smu;
+	int16_t	*pmecc_partial_syn;
+	int16_t	*pmecc_si;
+	int16_t	*pmecc_lmu; /* polynomal order */
+	int	*pmecc_mu;
+	int	*pmecc_dmu;
+	int	*pmecc_delta;
+};
+
+static struct atmel_nand_host pmecc_host;
+static struct nand_ecclayout atmel_pmecc_oobinfo;
+
+/*
+ * Return number of ecc bytes per sector according to sector size and
+ * correction capability
+ *
+ * Following table shows what at91 PMECC supported:
+ * Correction Capability	Sector_512_bytes	Sector_1024_bytes
+ * =====================	================	=================
+ *                2-bits                 4-bytes                  4-bytes
+ *                4-bits                 7-bytes                  7-bytes
+ *                8-bits                13-bytes                 14-bytes
+ *               12-bits                20-bytes                 21-bytes
+ *               24-bits                39-bytes                 42-bytes
+ */
+static int pmecc_get_ecc_bytes(int cap, int sector_size)
+{
+	int m = 12 + sector_size / 512;
+	return (m * cap + 7) / 8;
+}
+
+static void pmecc_config_ecc_layout(struct nand_ecclayout *layout,
+	int oobsize, int ecc_len)
+{
+	int i;
+
+	layout->eccbytes = ecc_len;
+
+	/* ECC will occupy the last ecc_len bytes continuously */
+	for (i = 0; i < ecc_len; i++)
+		layout->eccpos[i] = oobsize - ecc_len + i;
+
+	layout->oobfree[0].offset = 2;
+	layout->oobfree[0].length =
+		oobsize - ecc_len - layout->oobfree[0].offset;
+}
+
+static void __iomem *pmecc_get_alpha_to(struct atmel_nand_host *host)
+{
+	int table_size;
+
+	table_size = host->pmecc_sector_size == 512 ?
+		PMECC_INDEX_TABLE_SIZE_512 : PMECC_INDEX_TABLE_SIZE_1024;
+
+	/* the ALPHA lookup table is right behind the INDEX lookup table. */
+	return host->pmecc_rom_base + host->pmecc_index_table_offset +
+			table_size * sizeof(int16_t);
+}
+
+static void pmecc_data_free(struct atmel_nand_host *host)
+{
+	free(host->pmecc_partial_syn);
+	free(host->pmecc_si);
+	free(host->pmecc_lmu);
+	free(host->pmecc_smu);
+	free(host->pmecc_mu);
+	free(host->pmecc_dmu);
+	free(host->pmecc_delta);
+}
+
+static int pmecc_data_alloc(struct atmel_nand_host *host)
+{
+	const int cap = host->pmecc_corr_cap;
+	int size;
+
+	size = (2 * cap + 1) * sizeof(int16_t);
+	host->pmecc_partial_syn = malloc(size);
+	host->pmecc_si = malloc(size);
+	host->pmecc_lmu = malloc((cap + 1) * sizeof(int16_t));
+	host->pmecc_smu = malloc((cap + 2) * size);
+
+	size = (cap + 1) * sizeof(int);
+	host->pmecc_mu = malloc(size);
+	host->pmecc_dmu = malloc(size);
+	host->pmecc_delta = malloc(size);
+
+	if (host->pmecc_partial_syn &&
+			host->pmecc_si &&
+			host->pmecc_lmu &&
+			host->pmecc_smu &&
+			host->pmecc_mu &&
+			host->pmecc_dmu &&
+			host->pmecc_delta)
+		return 0;
+
+	/* error happened */
+	pmecc_data_free(host);
+	return -ENOMEM;
+
+}
+
+static void pmecc_gen_syndrome(struct mtd_info *mtd, int sector)
+{
+	struct nand_chip *nand_chip = mtd->priv;
+	struct atmel_nand_host *host = nand_chip->priv;
+	int i;
+	uint32_t value;
+
+	/* Fill odd syndromes */
+	for (i = 0; i < host->pmecc_corr_cap; i++) {
+		value = readl(&host->pmecc->rem_port[sector].rem[i / 2]);
+		if (i & 1)
+			value >>= 16;
+		value &= 0xffff;
+		host->pmecc_partial_syn[(2 * i) + 1] = (int16_t)value;
+	}
+}
+
+static void pmecc_substitute(struct mtd_info *mtd)
+{
+	struct nand_chip *nand_chip = mtd->priv;
+	struct atmel_nand_host *host = nand_chip->priv;
+	int16_t __iomem *alpha_to = host->pmecc_alpha_to;
+	int16_t __iomem *index_of = host->pmecc_index_of;
+	int16_t *partial_syn = host->pmecc_partial_syn;
+	const int cap = host->pmecc_corr_cap;
+	int16_t *si;
+	int i, j;
+
+	/* si[] is a table that holds the current syndrome value,
+	 * an element of that table belongs to the field
+	 */
+	si = host->pmecc_si;
+
+	memset(&si[1], 0, sizeof(int16_t) * (2 * cap - 1));
+
+	/* Computation 2t syndromes based on S(x) */
+	/* Odd syndromes */
+	for (i = 1; i < 2 * cap; i += 2) {
+		for (j = 0; j < host->pmecc_degree; j++) {
+			if (partial_syn[i] & (0x1 << j))
+				si[i] = readw(alpha_to + i * j) ^ si[i];
+		}
+	}
+	/* Even syndrome = (Odd syndrome) ** 2 */
+	for (i = 2, j = 1; j <= cap; i = ++j << 1) {
+		if (si[j] == 0) {
+			si[i] = 0;
+		} else {
+			int16_t tmp;
+
+			tmp = readw(index_of + si[j]);
+			tmp = (tmp * 2) % host->pmecc_cw_len;
+			si[i] = readw(alpha_to + tmp);
+		}
+	}
+}
+
+/*
+ * This function defines a Berlekamp iterative procedure for
+ * finding the value of the error location polynomial.
+ * The input is si[], initialize by pmecc_substitute().
+ * The output is smu[][].
+ *
+ * This function is written according to chip datasheet Chapter:
+ * Find the Error Location Polynomial Sigma(x) of Section:
+ * Programmable Multibit ECC Control (PMECC).
+ */
+static void pmecc_get_sigma(struct mtd_info *mtd)
+{
+	struct nand_chip *nand_chip = mtd->priv;
+	struct atmel_nand_host *host = nand_chip->priv;
+
+	int16_t *lmu = host->pmecc_lmu;
+	int16_t *si = host->pmecc_si;
+	int *mu = host->pmecc_mu;
+	int *dmu = host->pmecc_dmu;	/* Discrepancy */
+	int *delta = host->pmecc_delta; /* Delta order */
+	int cw_len = host->pmecc_cw_len;
+	const int16_t cap = host->pmecc_corr_cap;
+	const int num = 2 * cap + 1;
+	int16_t __iomem	*index_of = host->pmecc_index_of;
+	int16_t __iomem	*alpha_to = host->pmecc_alpha_to;
+	int i, j, k;
+	uint32_t dmu_0_count, tmp;
+	int16_t *smu = host->pmecc_smu;
+
+	/* index of largest delta */
+	int ro;
+	int largest;
+	int diff;
+
+	/* Init the Sigma(x) */
+	memset(smu, 0, sizeof(int16_t) * ARRAY_SIZE(smu));
+
+	dmu_0_count = 0;
+
+	/* First Row */
+
+	/* Mu */
+	mu[0] = -1;
+
+	smu[0] = 1;
+
+	/* discrepancy set to 1 */
+	dmu[0] = 1;
+	/* polynom order set to 0 */
+	lmu[0] = 0;
+	/* delta[0] = (mu[0] * 2 - lmu[0]) >> 1; */
+	delta[0] = -1;
+
+	/* Second Row */
+
+	/* Mu */
+	mu[1] = 0;
+	/* Sigma(x) set to 1 */
+	smu[num] = 1;
+
+	/* discrepancy set to S1 */
+	dmu[1] = si[1];
+
+	/* polynom order set to 0 */
+	lmu[1] = 0;
+
+	/* delta[1] = (mu[1] * 2 - lmu[1]) >> 1; */
+	delta[1] = 0;
+
+	for (i = 1; i <= cap; i++) {
+		mu[i + 1] = i << 1;
+		/* Begin Computing Sigma (Mu+1) and L(mu) */
+		/* check if discrepancy is set to 0 */
+		if (dmu[i] == 0) {
+			dmu_0_count++;
+
+			tmp = ((cap - (lmu[i] >> 1) - 1) / 2);
+			if ((cap - (lmu[i] >> 1) - 1) & 0x1)
+				tmp += 2;
+			else
+				tmp += 1;
+
+			if (dmu_0_count == tmp) {
+				for (j = 0; j <= (lmu[i] >> 1) + 1; j++)
+					smu[(cap + 1) * num + j] =
+							smu[i * num + j];
+
+				lmu[cap + 1] = lmu[i];
+				return;
+			}
+
+			/* copy polynom */
+			for (j = 0; j <= lmu[i] >> 1; j++)
+				smu[(i + 1) * num + j] = smu[i * num + j];
+
+			/* copy previous polynom order to the next */
+			lmu[i + 1] = lmu[i];
+		} else {
+			ro = 0;
+			largest = -1;
+			/* find largest delta with dmu != 0 */
+			for (j = 0; j < i; j++) {
+				if ((dmu[j]) && (delta[j] > largest)) {
+					largest = delta[j];
+					ro = j;
+				}
+			}
+
+			/* compute difference */
+			diff = (mu[i] - mu[ro]);
+
+			/* Compute degree of the new smu polynomial */
+			if ((lmu[i] >> 1) > ((lmu[ro] >> 1) + diff))
+				lmu[i + 1] = lmu[i];
+			else
+				lmu[i + 1] = ((lmu[ro] >> 1) + diff) * 2;
+
+			/* Init smu[i+1] with 0 */
+			for (k = 0; k < num; k++)
+				smu[(i + 1) * num + k] = 0;
+
+			/* Compute smu[i+1] */
+			for (k = 0; k <= lmu[ro] >> 1; k++) {
+				int16_t a, b, c;
+
+				if (!(smu[ro * num + k] && dmu[i]))
+					continue;
+				a = readw(index_of + dmu[i]);
+				b = readw(index_of + dmu[ro]);
+				c = readw(index_of + smu[ro * num + k]);
+				tmp = a + (cw_len - b) + c;
+				a = readw(alpha_to + tmp % cw_len);
+				smu[(i + 1) * num + (k + diff)] = a;
+			}
+
+			for (k = 0; k <= lmu[i] >> 1; k++)
+				smu[(i + 1) * num + k] ^= smu[i * num + k];
+		}
+
+		/* End Computing Sigma (Mu+1) and L(mu) */
+		/* In either case compute delta */
+		delta[i + 1] = (mu[i + 1] * 2 - lmu[i + 1]) >> 1;
+
+		/* Do not compute discrepancy for the last iteration */
+		if (i >= cap)
+			continue;
+
+		for (k = 0; k <= (lmu[i + 1] >> 1); k++) {
+			tmp = 2 * (i - 1);
+			if (k == 0) {
+				dmu[i + 1] = si[tmp + 3];
+			} else if (smu[(i + 1) * num + k] && si[tmp + 3 - k]) {
+				int16_t a, b, c;
+				a = readw(index_of +
+						smu[(i + 1) * num + k]);
+				b = si[2 * (i - 1) + 3 - k];
+				c = readw(index_of + b);
+				tmp = a + c;
+				tmp %= cw_len;
+				dmu[i + 1] = readw(alpha_to + tmp) ^
+					dmu[i + 1];
+			}
+		}
+	}
+}
+
+static int pmecc_err_location(struct mtd_info *mtd)
+{
+	struct nand_chip *nand_chip = mtd->priv;
+	struct atmel_nand_host *host = nand_chip->priv;
+	const int cap = host->pmecc_corr_cap;
+	const int num = 2 * cap + 1;
+	int sector_size = host->pmecc_sector_size;
+	int err_nbr = 0;	/* number of error */
+	int roots_nbr;		/* number of roots */
+	int i;
+	uint32_t val;
+	int16_t *smu = host->pmecc_smu;
+	int timeout = PMECC_MAX_TIMEOUT_US;
+
+	writel(PMERRLOC_DISABLE, &host->pmerrloc->eldis);
+
+	for (i = 0; i <= host->pmecc_lmu[cap + 1] >> 1; i++) {
+		writel(smu[(cap + 1) * num + i], &host->pmerrloc->sigma[i]);
+		err_nbr++;
+	}
+
+	val = PMERRLOC_ELCFG_NUM_ERRORS(err_nbr - 1);
+	if (sector_size == 1024)
+		val |= PMERRLOC_ELCFG_SECTOR_1024;
+
+	writel(val, &host->pmerrloc->elcfg);
+	writel(sector_size * 8 + host->pmecc_degree * cap,
+			&host->pmerrloc->elen);
+
+	while (--timeout) {
+		if (readl(&host->pmerrloc->elisr) & PMERRLOC_CALC_DONE)
+			break;
+		WATCHDOG_RESET();
+		udelay(1);
+	}
+
+	if (!timeout) {
+		dev_err(host->dev, "atmel_nand : Timeout to calculate PMECC error location\n");
+		return -1;
+	}
+
+	roots_nbr = (readl(&host->pmerrloc->elisr) & PMERRLOC_ERR_NUM_MASK)
+			>> 8;
+	/* Number of roots == degree of smu hence <= cap */
+	if (roots_nbr == host->pmecc_lmu[cap + 1] >> 1)
+		return err_nbr - 1;
+
+	/* Number of roots does not match the degree of smu
+	 * unable to correct error */
+	return -1;
+}
+
+static void pmecc_correct_data(struct mtd_info *mtd, uint8_t *buf, uint8_t *ecc,
+		int sector_num, int extra_bytes, int err_nbr)
+{
+	struct nand_chip *nand_chip = mtd->priv;
+	struct atmel_nand_host *host = nand_chip->priv;
+	int i = 0;
+	int byte_pos, bit_pos, sector_size, pos;
+	uint32_t tmp;
+	uint8_t err_byte;
+
+	sector_size = host->pmecc_sector_size;
+
+	while (err_nbr) {
+		tmp = readl(&host->pmerrloc->el[i]) - 1;
+		byte_pos = tmp / 8;
+		bit_pos  = tmp % 8;
+
+		if (byte_pos >= (sector_size + extra_bytes))
+			BUG();	/* should never happen */
+
+		if (byte_pos < sector_size) {
+			err_byte = *(buf + byte_pos);
+			*(buf + byte_pos) ^= (1 << bit_pos);
+
+			pos = sector_num * host->pmecc_sector_size + byte_pos;
+			dev_dbg(host->dev, "Bit flip in data area, byte_pos: %d, bit_pos: %d, 0x%02x -> 0x%02x\n",
+				pos, bit_pos, err_byte, *(buf + byte_pos));
+		} else {
+			/* Bit flip in OOB area */
+			tmp = sector_num * host->pmecc_bytes_per_sector
+					+ (byte_pos - sector_size);
+			err_byte = ecc[tmp];
+			ecc[tmp] ^= (1 << bit_pos);
+
+			pos = tmp + nand_chip->ecc.layout->eccpos[0];
+			dev_dbg(host->dev, "Bit flip in OOB, oob_byte_pos: %d, bit_pos: %d, 0x%02x -> 0x%02x\n",
+				pos, bit_pos, err_byte, ecc[tmp]);
+		}
+
+		i++;
+		err_nbr--;
+	}
+
+	return;
+}
+
+static int pmecc_correction(struct mtd_info *mtd, u32 pmecc_stat, uint8_t *buf,
+	u8 *ecc)
+{
+	struct nand_chip *nand_chip = mtd->priv;
+	struct atmel_nand_host *host = nand_chip->priv;
+	int i, err_nbr, eccbytes;
+	uint8_t *buf_pos;
+
+	eccbytes = nand_chip->ecc.bytes;
+	for (i = 0; i < eccbytes; i++)
+		if (ecc[i] != 0xff)
+			goto normal_check;
+	/* Erased page, return OK */
+	return 0;
+
+normal_check:
+	for (i = 0; i < host->pmecc_sector_number; i++) {
+		err_nbr = 0;
+		if (pmecc_stat & 0x1) {
+			buf_pos = buf + i * host->pmecc_sector_size;
+
+			pmecc_gen_syndrome(mtd, i);
+			pmecc_substitute(mtd);
+			pmecc_get_sigma(mtd);
+
+			err_nbr = pmecc_err_location(mtd);
+			if (err_nbr == -1) {
+				dev_err(host->dev, "PMECC: Too many errors\n");
+				mtd->ecc_stats.failed++;
+				return -EIO;
+			} else {
+				pmecc_correct_data(mtd, buf_pos, ecc, i,
+					host->pmecc_bytes_per_sector, err_nbr);
+				mtd->ecc_stats.corrected += err_nbr;
+			}
+		}
+		pmecc_stat >>= 1;
+	}
+
+	return 0;
+}
+
+static int atmel_nand_pmecc_read_page(struct mtd_info *mtd,
+	struct nand_chip *chip, uint8_t *buf, int oob_required, int page)
+{
+	struct atmel_nand_host *host = chip->priv;
+	int eccsize = chip->ecc.size;
+	uint8_t *oob = chip->oob_poi;
+	uint32_t *eccpos = chip->ecc.layout->eccpos;
+	uint32_t stat;
+	int timeout = PMECC_MAX_TIMEOUT_US;
+
+	pmecc_writel(host->pmecc, ctrl, PMECC_CTRL_RST);
+	pmecc_writel(host->pmecc, ctrl, PMECC_CTRL_DISABLE);
+	pmecc_writel(host->pmecc, cfg, ((pmecc_readl(host->pmecc, cfg))
+		& ~PMECC_CFG_WRITE_OP) | PMECC_CFG_AUTO_ENABLE);
+
+	pmecc_writel(host->pmecc, ctrl, PMECC_CTRL_ENABLE);
+	pmecc_writel(host->pmecc, ctrl, PMECC_CTRL_DATA);
+
+	chip->read_buf(mtd, buf, eccsize);
+	chip->read_buf(mtd, oob, mtd->oobsize);
+
+	while (--timeout) {
+		if (!(pmecc_readl(host->pmecc, sr) & PMECC_SR_BUSY))
+			break;
+		WATCHDOG_RESET();
+		udelay(1);
+	}
+
+	if (!timeout) {
+		dev_err(host->dev, "atmel_nand : Timeout to read PMECC page\n");
+		return -1;
+	}
+
+	stat = pmecc_readl(host->pmecc, isr);
+	if (stat != 0)
+		if (pmecc_correction(mtd, stat, buf, &oob[eccpos[0]]) != 0)
+			return -EIO;
+
+	return 0;
+}
+
+static int atmel_nand_pmecc_write_page(struct mtd_info *mtd,
+		struct nand_chip *chip, const uint8_t *buf,
+		int oob_required)
+{
+	struct atmel_nand_host *host = chip->priv;
+	uint32_t *eccpos = chip->ecc.layout->eccpos;
+	int i, j;
+	int timeout = PMECC_MAX_TIMEOUT_US;
+
+	pmecc_writel(host->pmecc, ctrl, PMECC_CTRL_RST);
+	pmecc_writel(host->pmecc, ctrl, PMECC_CTRL_DISABLE);
+
+	pmecc_writel(host->pmecc, cfg, (pmecc_readl(host->pmecc, cfg) |
+		PMECC_CFG_WRITE_OP) & ~PMECC_CFG_AUTO_ENABLE);
+
+	pmecc_writel(host->pmecc, ctrl, PMECC_CTRL_ENABLE);
+	pmecc_writel(host->pmecc, ctrl, PMECC_CTRL_DATA);
+
+	chip->write_buf(mtd, (u8 *)buf, mtd->writesize);
+
+	while (--timeout) {
+		if (!(pmecc_readl(host->pmecc, sr) & PMECC_SR_BUSY))
+			break;
+		WATCHDOG_RESET();
+		udelay(1);
+	}
+
+	if (!timeout) {
+		dev_err(host->dev, "atmel_nand : Timeout to read PMECC status, fail to write PMECC in oob\n");
+		goto out;
+	}
+
+	for (i = 0; i < host->pmecc_sector_number; i++) {
+		for (j = 0; j < host->pmecc_bytes_per_sector; j++) {
+			int pos;
+
+			pos = i * host->pmecc_bytes_per_sector + j;
+			chip->oob_poi[eccpos[pos]] =
+				readb(&host->pmecc->ecc_port[i].ecc[j]);
+		}
+	}
+	chip->write_buf(mtd, chip->oob_poi, mtd->oobsize);
+out:
+	return 0;
+}
+
+static void atmel_pmecc_core_init(struct mtd_info *mtd)
+{
+	struct nand_chip *nand_chip = mtd->priv;
+	struct atmel_nand_host *host = nand_chip->priv;
+	uint32_t val = 0;
+	struct nand_ecclayout *ecc_layout;
+
+	pmecc_writel(host->pmecc, ctrl, PMECC_CTRL_RST);
+	pmecc_writel(host->pmecc, ctrl, PMECC_CTRL_DISABLE);
+
+	switch (host->pmecc_corr_cap) {
+	case 2:
+		val = PMECC_CFG_BCH_ERR2;
+		break;
+	case 4:
+		val = PMECC_CFG_BCH_ERR4;
+		break;
+	case 8:
+		val = PMECC_CFG_BCH_ERR8;
+		break;
+	case 12:
+		val = PMECC_CFG_BCH_ERR12;
+		break;
+	case 24:
+		val = PMECC_CFG_BCH_ERR24;
+		break;
+	}
+
+	if (host->pmecc_sector_size == 512)
+		val |= PMECC_CFG_SECTOR512;
+	else if (host->pmecc_sector_size == 1024)
+		val |= PMECC_CFG_SECTOR1024;
+
+	switch (host->pmecc_sector_number) {
+	case 1:
+		val |= PMECC_CFG_PAGE_1SECTOR;
+		break;
+	case 2:
+		val |= PMECC_CFG_PAGE_2SECTORS;
+		break;
+	case 4:
+		val |= PMECC_CFG_PAGE_4SECTORS;
+		break;
+	case 8:
+		val |= PMECC_CFG_PAGE_8SECTORS;
+		break;
+	}
+
+	val |= (PMECC_CFG_READ_OP | PMECC_CFG_SPARE_DISABLE
+		| PMECC_CFG_AUTO_DISABLE);
+	pmecc_writel(host->pmecc, cfg, val);
+
+	ecc_layout = nand_chip->ecc.layout;
+	pmecc_writel(host->pmecc, sarea, mtd->oobsize - 1);
+	pmecc_writel(host->pmecc, saddr, ecc_layout->eccpos[0]);
+	pmecc_writel(host->pmecc, eaddr,
+			ecc_layout->eccpos[ecc_layout->eccbytes - 1]);
+	/* See datasheet about PMECC Clock Control Register */
+	pmecc_writel(host->pmecc, clk, PMECC_CLK_133MHZ);
+	pmecc_writel(host->pmecc, idr, 0xff);
+	pmecc_writel(host->pmecc, ctrl, PMECC_CTRL_ENABLE);
+}
+
+#ifdef CONFIG_SYS_NAND_ONFI_DETECTION
+/*
+ * get_onfi_ecc_param - Get ECC requirement from ONFI parameters
+ * @ecc_bits: store the ONFI ECC correct bits capbility
+ * @sector_size: in how many bytes that ONFI require to correct @ecc_bits
+ *
+ * Returns -1 if ONFI parameters is not supported. In this case @ecc_bits,
+ * @sector_size are initialize to 0.
+ * Return 0 if success to get the ECC requirement.
+ */
+static int get_onfi_ecc_param(struct nand_chip *chip,
+		int *ecc_bits, int *sector_size)
+{
+	*ecc_bits = *sector_size = 0;
+
+	if (chip->onfi_params.ecc_bits == 0xff)
+		/* TODO: the sector_size and ecc_bits need to be find in
+		 * extended ecc parameter, currently we don't support it.
+		 */
+		return -1;
+
+	*ecc_bits = chip->onfi_params.ecc_bits;
+
+	/* The default sector size (ecc codeword size) is 512 */
+	*sector_size = 512;
+
+	return 0;
+}
+
+/*
+ * pmecc_choose_ecc - Get ecc requirement from ONFI parameters. If
+ *                    pmecc_corr_cap or pmecc_sector_size is 0, then set it as
+ *                    ONFI ECC parameters.
+ * @host: point to an atmel_nand_host structure.
+ *        if host->pmecc_corr_cap is 0 then set it as the ONFI ecc_bits.
+ *        if host->pmecc_sector_size is 0 then set it as the ONFI sector_size.
+ * @chip: point to an nand_chip structure.
+ * @cap: store the ONFI ECC correct bits capbility
+ * @sector_size: in how many bytes that ONFI require to correct @ecc_bits
+ *
+ * Return 0 if success. otherwise return the error code.
+ */
+static int pmecc_choose_ecc(struct atmel_nand_host *host,
+		struct nand_chip *chip,
+		int *cap, int *sector_size)
+{
+	/* Get ECC requirement from ONFI parameters */
+	*cap = *sector_size = 0;
+	if (chip->onfi_version) {
+		if (!get_onfi_ecc_param(chip, cap, sector_size)) {
+			MTDDEBUG(MTD_DEBUG_LEVEL1, "ONFI params, minimum required ECC: %d bits in %d bytes\n",
+				*cap, *sector_size);
+		} else {
+			dev_info(host->dev, "NAND chip ECC reqirement is in Extended ONFI parameter, we don't support yet.\n");
+		}
+	} else {
+		dev_info(host->dev, "NAND chip is not ONFI compliant, assume ecc_bits is 2 in 512 bytes");
+	}
+	if (*cap == 0 && *sector_size == 0) {
+		/* Non-ONFI compliant or use extended ONFI parameters */
+		*cap = 2;
+		*sector_size = 512;
+	}
+
+	/* If head file doesn't specify then use the one in ONFI parameters */
+	if (host->pmecc_corr_cap == 0) {
+		/* use the most fitable ecc bits (the near bigger one ) */
+		if (*cap <= 2)
+			host->pmecc_corr_cap = 2;
+		else if (*cap <= 4)
+			host->pmecc_corr_cap = 4;
+		else if (*cap <= 8)
+			host->pmecc_corr_cap = 8;
+		else if (*cap <= 12)
+			host->pmecc_corr_cap = 12;
+		else if (*cap <= 24)
+			host->pmecc_corr_cap = 24;
+		else
+			return -EINVAL;
+	}
+	if (host->pmecc_sector_size == 0) {
+		/* use the most fitable sector size (the near smaller one ) */
+		if (*sector_size >= 1024)
+			host->pmecc_sector_size = 1024;
+		else if (*sector_size >= 512)
+			host->pmecc_sector_size = 512;
+		else
+			return -EINVAL;
+	}
+	return 0;
+}
+#endif
+
+static int atmel_pmecc_nand_init_params(struct nand_chip *nand,
+		struct mtd_info *mtd)
+{
+	struct atmel_nand_host *host;
+	int cap, sector_size;
+
+	host = nand->priv = &pmecc_host;
+
+	nand->ecc.mode = NAND_ECC_HW;
+	nand->ecc.calculate = NULL;
+	nand->ecc.correct = NULL;
+	nand->ecc.hwctl = NULL;
+
+#ifdef CONFIG_SYS_NAND_ONFI_DETECTION
+	host->pmecc_corr_cap = host->pmecc_sector_size = 0;
+
+#ifdef CONFIG_PMECC_CAP
+	host->pmecc_corr_cap = CONFIG_PMECC_CAP;
+#endif
+#ifdef CONFIG_PMECC_SECTOR_SIZE
+	host->pmecc_sector_size = CONFIG_PMECC_SECTOR_SIZE;
+#endif
+	/* Get ECC requirement of ONFI parameters. And if CONFIG_PMECC_CAP or
+	 * CONFIG_PMECC_SECTOR_SIZE not defined, then use ecc_bits, sector_size
+	 * from ONFI.
+	 */
+	if (pmecc_choose_ecc(host, nand, &cap, &sector_size)) {
+		dev_err(host->dev, "The NAND flash's ECC requirement(ecc_bits: %d, sector_size: %d) are not support!",
+				cap, sector_size);
+		return -EINVAL;
+	}
+
+	if (cap > host->pmecc_corr_cap)
+		dev_info(host->dev, "WARNING: Using different ecc correct bits(%d bit) from Nand ONFI ECC reqirement (%d bit).\n",
+				host->pmecc_corr_cap, cap);
+	if (sector_size < host->pmecc_sector_size)
+		dev_info(host->dev, "WARNING: Using different ecc correct sector size (%d bytes) from Nand ONFI ECC reqirement (%d bytes).\n",
+				host->pmecc_sector_size, sector_size);
+#else	/* CONFIG_SYS_NAND_ONFI_DETECTION */
+	host->pmecc_corr_cap = CONFIG_PMECC_CAP;
+	host->pmecc_sector_size = CONFIG_PMECC_SECTOR_SIZE;
+#endif
+
+	cap = host->pmecc_corr_cap;
+	sector_size = host->pmecc_sector_size;
+
+	/* TODO: need check whether cap & sector_size is validate */
+
+	if (host->pmecc_sector_size == 512)
+		host->pmecc_index_table_offset = ATMEL_PMECC_INDEX_OFFSET_512;
+	else
+		host->pmecc_index_table_offset = ATMEL_PMECC_INDEX_OFFSET_1024;
+
+	MTDDEBUG(MTD_DEBUG_LEVEL1,
+		"Initialize PMECC params, cap: %d, sector: %d\n",
+		cap, sector_size);
+
+	host->pmecc = (struct pmecc_regs __iomem *) ATMEL_BASE_PMECC;
+	host->pmerrloc = (struct pmecc_errloc_regs __iomem *)
+			ATMEL_BASE_PMERRLOC;
+	host->pmecc_rom_base = (void __iomem *) ATMEL_BASE_ROM;
+
+	/* ECC is calculated for the whole page (1 step) */
+	nand->ecc.size = mtd->writesize;
+
+	/* set ECC page size and oob layout */
+	switch (mtd->writesize) {
+	case 2048:
+	case 4096:
+	case 8192:
+		host->pmecc_degree = (sector_size == 512) ?
+			PMECC_GF_DIMENSION_13 : PMECC_GF_DIMENSION_14;
+		host->pmecc_cw_len = (1 << host->pmecc_degree) - 1;
+		host->pmecc_sector_number = mtd->writesize / sector_size;
+		host->pmecc_bytes_per_sector = pmecc_get_ecc_bytes(
+			cap, sector_size);
+		host->pmecc_alpha_to = pmecc_get_alpha_to(host);
+		host->pmecc_index_of = host->pmecc_rom_base +
+			host->pmecc_index_table_offset;
+
+		nand->ecc.steps = 1;
+		nand->ecc.bytes = host->pmecc_bytes_per_sector *
+				       host->pmecc_sector_number;
+
+		if (nand->ecc.bytes > MTD_MAX_ECCPOS_ENTRIES_LARGE) {
+			dev_err(host->dev, "too large eccpos entries. max support ecc.bytes is %d\n",
+					MTD_MAX_ECCPOS_ENTRIES_LARGE);
+			return -EINVAL;
+		}
+
+		if (nand->ecc.bytes > mtd->oobsize - 2) {
+			dev_err(host->dev, "No room for ECC bytes\n");
+			return -EINVAL;
+		}
+		pmecc_config_ecc_layout(&atmel_pmecc_oobinfo,
+					mtd->oobsize,
+					nand->ecc.bytes);
+		nand->ecc.layout = &atmel_pmecc_oobinfo;
+		break;
+	case 512:
+	case 1024:
+		/* TODO */
+		dev_err(host->dev, "Unsupported page size for PMECC, use Software ECC\n");
+	default:
+		/* page size not handled by HW ECC */
+		/* switching back to soft ECC */
+		nand->ecc.mode = NAND_ECC_SOFT;
+		nand->ecc.read_page = NULL;
+		nand->ecc.postpad = 0;
+		nand->ecc.prepad = 0;
+		nand->ecc.bytes = 0;
+		return 0;
+	}
+
+	/* Allocate data for PMECC computation */
+	if (pmecc_data_alloc(host)) {
+		dev_err(host->dev, "Cannot allocate memory for PMECC computation!\n");
+		return -ENOMEM;
+	}
+
+	nand->ecc.read_page = atmel_nand_pmecc_read_page;
+	nand->ecc.write_page = atmel_nand_pmecc_write_page;
+	nand->ecc.strength = cap;
+
+	atmel_pmecc_core_init(mtd);
+
+	return 0;
+}
+
+#else
+
+/* oob layout for large page size
+ * bad block info is on bytes 0 and 1
+ * the bytes have to be consecutives to avoid
+ * several NAND_CMD_RNDOUT during read
+ */
+static struct nand_ecclayout atmel_oobinfo_large = {
+	.eccbytes = 4,
+	.eccpos = {60, 61, 62, 63},
+	.oobfree = {
+		{2, 58}
+	},
+};
+
+/* oob layout for small page size
+ * bad block info is on bytes 4 and 5
+ * the bytes have to be consecutives to avoid
+ * several NAND_CMD_RNDOUT during read
+ */
+static struct nand_ecclayout atmel_oobinfo_small = {
+	.eccbytes = 4,
+	.eccpos = {0, 1, 2, 3},
+	.oobfree = {
+		{6, 10}
+	},
+};
+
+/*
+ * Calculate HW ECC
+ *
+ * function called after a write
+ *
+ * mtd:        MTD block structure
+ * dat:        raw data (unused)
+ * ecc_code:   buffer for ECC
+ */
+static int atmel_nand_calculate(struct mtd_info *mtd,
+		const u_char *dat, unsigned char *ecc_code)
+{
+	unsigned int ecc_value;
+
+	/* get the first 2 ECC bytes */
+	ecc_value = ecc_readl(CONFIG_SYS_NAND_ECC_BASE, PR);
+
+	ecc_code[0] = ecc_value & 0xFF;
+	ecc_code[1] = (ecc_value >> 8) & 0xFF;
+
+	/* get the last 2 ECC bytes */
+	ecc_value = ecc_readl(CONFIG_SYS_NAND_ECC_BASE, NPR) & ATMEL_ECC_NPARITY;
+
+	ecc_code[2] = ecc_value & 0xFF;
+	ecc_code[3] = (ecc_value >> 8) & 0xFF;
+
+	return 0;
+}
+
+/*
+ * HW ECC read page function
+ *
+ * mtd:        mtd info structure
+ * chip:       nand chip info structure
+ * buf:        buffer to store read data
+ * oob_required:    caller expects OOB data read to chip->oob_poi
+ */
+static int atmel_nand_read_page(struct mtd_info *mtd, struct nand_chip *chip,
+				uint8_t *buf, int oob_required, int page)
+{
+	int eccsize = chip->ecc.size;
+	int eccbytes = chip->ecc.bytes;
+	uint32_t *eccpos = chip->ecc.layout->eccpos;
+	uint8_t *p = buf;
+	uint8_t *oob = chip->oob_poi;
+	uint8_t *ecc_pos;
+	int stat;
+
+	/* read the page */
+	chip->read_buf(mtd, p, eccsize);
+
+	/* move to ECC position if needed */
+	if (eccpos[0] != 0) {
+		/* This only works on large pages
+		 * because the ECC controller waits for
+		 * NAND_CMD_RNDOUTSTART after the
+		 * NAND_CMD_RNDOUT.
+		 * anyway, for small pages, the eccpos[0] == 0
+		 */
+		chip->cmdfunc(mtd, NAND_CMD_RNDOUT,
+				mtd->writesize + eccpos[0], -1);
+	}
+
+	/* the ECC controller needs to read the ECC just after the data */
+	ecc_pos = oob + eccpos[0];
+	chip->read_buf(mtd, ecc_pos, eccbytes);
+
+	/* check if there's an error */
+	stat = chip->ecc.correct(mtd, p, oob, NULL);
+
+	if (stat < 0)
+		mtd->ecc_stats.failed++;
+	else
+		mtd->ecc_stats.corrected += stat;
+
+	/* get back to oob start (end of page) */
+	chip->cmdfunc(mtd, NAND_CMD_RNDOUT, mtd->writesize, -1);
+
+	/* read the oob */
+	chip->read_buf(mtd, oob, mtd->oobsize);
+
+	return 0;
+}
+
+/*
+ * HW ECC Correction
+ *
+ * function called after a read
+ *
+ * mtd:        MTD block structure
+ * dat:        raw data read from the chip
+ * read_ecc:   ECC from the chip (unused)
+ * isnull:     unused
+ *
+ * Detect and correct a 1 bit error for a page
+ */
+static int atmel_nand_correct(struct mtd_info *mtd, u_char *dat,
+		u_char *read_ecc, u_char *isnull)
+{
+	struct nand_chip *nand_chip = mtd->priv;
+	unsigned int ecc_status;
+	unsigned int ecc_word, ecc_bit;
+
+	/* get the status from the Status Register */
+	ecc_status = ecc_readl(CONFIG_SYS_NAND_ECC_BASE, SR);
+
+	/* if there's no error */
+	if (likely(!(ecc_status & ATMEL_ECC_RECERR)))
+		return 0;
+
+	/* get error bit offset (4 bits) */
+	ecc_bit = ecc_readl(CONFIG_SYS_NAND_ECC_BASE, PR) & ATMEL_ECC_BITADDR;
+	/* get word address (12 bits) */
+	ecc_word = ecc_readl(CONFIG_SYS_NAND_ECC_BASE, PR) & ATMEL_ECC_WORDADDR;
+	ecc_word >>= 4;
+
+	/* if there are multiple errors */
+	if (ecc_status & ATMEL_ECC_MULERR) {
+		/* check if it is a freshly erased block
+		 * (filled with 0xff) */
+		if ((ecc_bit == ATMEL_ECC_BITADDR)
+				&& (ecc_word == (ATMEL_ECC_WORDADDR >> 4))) {
+			/* the block has just been erased, return OK */
+			return 0;
+		}
+		/* it doesn't seems to be a freshly
+		 * erased block.
+		 * We can't correct so many errors */
+		dev_warn(host->dev, "atmel_nand : multiple errors detected."
+				" Unable to correct.\n");
+		return -EIO;
+	}
+
+	/* if there's a single bit error : we can correct it */
+	if (ecc_status & ATMEL_ECC_ECCERR) {
+		/* there's nothing much to do here.
+		 * the bit error is on the ECC itself.
+		 */
+		dev_warn(host->dev, "atmel_nand : one bit error on ECC code."
+				" Nothing to correct\n");
+		return 0;
+	}
+
+	dev_warn(host->dev, "atmel_nand : one bit error on data."
+			" (word offset in the page :"
+			" 0x%x bit offset : 0x%x)\n",
+			ecc_word, ecc_bit);
+	/* correct the error */
+	if (nand_chip->options & NAND_BUSWIDTH_16) {
+		/* 16 bits words */
+		((unsigned short *) dat)[ecc_word] ^= (1 << ecc_bit);
+	} else {
+		/* 8 bits words */
+		dat[ecc_word] ^= (1 << ecc_bit);
+	}
+	dev_warn(host->dev, "atmel_nand : error corrected\n");
+	return 1;
+}
+
+/*
+ * Enable HW ECC : unused on most chips
+ */
+static void atmel_nand_hwctl(struct mtd_info *mtd, int mode)
+{
+}
+
+int atmel_hwecc_nand_init_param(struct nand_chip *nand, struct mtd_info *mtd)
+{
+	nand->ecc.mode = NAND_ECC_HW;
+	nand->ecc.calculate = atmel_nand_calculate;
+	nand->ecc.correct = atmel_nand_correct;
+	nand->ecc.hwctl = atmel_nand_hwctl;
+	nand->ecc.read_page = atmel_nand_read_page;
+	nand->ecc.bytes = 4;
+
+	if (nand->ecc.mode == NAND_ECC_HW) {
+		/* ECC is calculated for the whole page (1 step) */
+		nand->ecc.size = mtd->writesize;
+
+		/* set ECC page size and oob layout */
+		switch (mtd->writesize) {
+		case 512:
+			nand->ecc.layout = &atmel_oobinfo_small;
+			ecc_writel(CONFIG_SYS_NAND_ECC_BASE, MR,
+					ATMEL_ECC_PAGESIZE_528);
+			break;
+		case 1024:
+			nand->ecc.layout = &atmel_oobinfo_large;
+			ecc_writel(CONFIG_SYS_NAND_ECC_BASE, MR,
+					ATMEL_ECC_PAGESIZE_1056);
+			break;
+		case 2048:
+			nand->ecc.layout = &atmel_oobinfo_large;
+			ecc_writel(CONFIG_SYS_NAND_ECC_BASE, MR,
+					ATMEL_ECC_PAGESIZE_2112);
+			break;
+		case 4096:
+			nand->ecc.layout = &atmel_oobinfo_large;
+			ecc_writel(CONFIG_SYS_NAND_ECC_BASE, MR,
+					ATMEL_ECC_PAGESIZE_4224);
+			break;
+		default:
+			/* page size not handled by HW ECC */
+			/* switching back to soft ECC */
+			nand->ecc.mode = NAND_ECC_SOFT;
+			nand->ecc.calculate = NULL;
+			nand->ecc.correct = NULL;
+			nand->ecc.hwctl = NULL;
+			nand->ecc.read_page = NULL;
+			nand->ecc.postpad = 0;
+			nand->ecc.prepad = 0;
+			nand->ecc.bytes = 0;
+			break;
+		}
+	}
+
+	return 0;
+}
+
+#endif /* CONFIG_ATMEL_NAND_HW_PMECC */
+
+#endif /* CONFIG_ATMEL_NAND_HWECC */
+
+static void at91_nand_hwcontrol(struct mtd_info *mtd,
+					 int cmd, unsigned int ctrl)
+{
+	struct nand_chip *this = mtd->priv;
+
+	if (ctrl & NAND_CTRL_CHANGE) {
+		ulong IO_ADDR_W = (ulong) this->IO_ADDR_W;
+		IO_ADDR_W &= ~(CONFIG_SYS_NAND_MASK_ALE
+			     | CONFIG_SYS_NAND_MASK_CLE);
+
+		if (ctrl & NAND_CLE)
+			IO_ADDR_W |= CONFIG_SYS_NAND_MASK_CLE;
+		if (ctrl & NAND_ALE)
+			IO_ADDR_W |= CONFIG_SYS_NAND_MASK_ALE;
+
+#ifdef CONFIG_SYS_NAND_ENABLE_PIN
+		gpio_set_value(CONFIG_SYS_NAND_ENABLE_PIN, !(ctrl & NAND_NCE));
+#endif
+		this->IO_ADDR_W = (void *) IO_ADDR_W;
+	}
+
+	if (cmd != NAND_CMD_NONE)
+		writeb(cmd, this->IO_ADDR_W);
+}
+
+#ifdef CONFIG_SYS_NAND_READY_PIN
+static int at91_nand_ready(struct mtd_info *mtd)
+{
+	return gpio_get_value(CONFIG_SYS_NAND_READY_PIN);
+}
+#endif
+
+#ifndef CONFIG_SYS_NAND_BASE_LIST
+#define CONFIG_SYS_NAND_BASE_LIST { CONFIG_SYS_NAND_BASE }
+#endif
+static struct nand_chip nand_chip[CONFIG_SYS_MAX_NAND_DEVICE];
+static ulong base_addr[CONFIG_SYS_MAX_NAND_DEVICE] = CONFIG_SYS_NAND_BASE_LIST;
+
+int atmel_nand_chip_init(int devnum, ulong base_addr)
+{
+	int ret;
+	struct mtd_info *mtd = &nand_info[devnum];
+	struct nand_chip *nand = &nand_chip[devnum];
+
+	mtd->priv = nand;
+	nand->IO_ADDR_R = nand->IO_ADDR_W = (void  __iomem *)base_addr;
+
+#ifdef CONFIG_NAND_ECC_BCH
+	nand->ecc.mode = NAND_ECC_SOFT_BCH;
+#else
+	nand->ecc.mode = NAND_ECC_SOFT;
+#endif
+#ifdef CONFIG_SYS_NAND_DBW_16
+	nand->options = NAND_BUSWIDTH_16;
+#endif
+	nand->cmd_ctrl = at91_nand_hwcontrol;
+#ifdef CONFIG_SYS_NAND_READY_PIN
+	nand->dev_ready = at91_nand_ready;
+#endif
+	nand->chip_delay = 75;
+
+	ret = nand_scan_ident(mtd, CONFIG_SYS_NAND_MAX_CHIPS, NULL);
+	if (ret)
+		return ret;
+
+#ifdef CONFIG_ATMEL_NAND_HWECC
+#ifdef CONFIG_ATMEL_NAND_HW_PMECC
+	ret = atmel_pmecc_nand_init_params(nand, mtd);
+#else
+	ret = atmel_hwecc_nand_init_param(nand, mtd);
+#endif
+	if (ret)
+		return ret;
+#endif
+
+	ret = nand_scan_tail(mtd);
+	if (!ret)
+		nand_register(devnum);
+
+	return ret;
+}
+
+void board_nand_init(void)
+{
+	int i;
+	for (i = 0; i < CONFIG_SYS_MAX_NAND_DEVICE; i++)
+		if (atmel_nand_chip_init(i, base_addr[i]))
+			dev_err(host->dev, "atmel_nand: Fail to initialize #%d chip",
+				i);
+}