NAND: add NAND driver for S3C64XX

Based on the original S3C64XX NAND driver by Samsung for U-Boot 1.1.6.

Signed-off-by: Guennadi Liakhovetski <lg@denx.de>

2 files changed, 320 insertions, 0 deletions

diff --git a/drivers/mtd/nand/Makefile b/drivers/mtd/nand/Makefile
index 1923310..b0abe6e 100644
--- a/drivers/mtd/nand/Makefile
+++ b/drivers/mtd/nand/Makefile
@@ -37,6 +37,7 @@ endif
 
 COBJS-$(CONFIG_NAND_FSL_ELBC) += fsl_elbc_nand.o
 COBJS-$(CONFIG_NAND_FSL_UPM) += fsl_upm.o
+COBJS-$(CONFIG_NAND_S3C64XX) += s3c64xx.o
 endif
 
 COBJS	:= $(COBJS-y)
diff --git a/drivers/mtd/nand/s3c64xx.c b/drivers/mtd/nand/s3c64xx.c
new file mode 100644
index 0000000..159fe76
--- /dev/null
+++ b/drivers/mtd/nand/s3c64xx.c
@@ -0,0 +1,319 @@
+/*
+ * (C) Copyright 2006 DENX Software Engineering
+ *
+ * Implementation for U-Boot 1.1.6 by Samsung
+ *
+ * (C) Copyright 2008
+ * Guennadi Liakhovetki, DENX Software Engineering, <lg@denx.de>
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <common.h>
+
+#include <nand.h>
+#include <s3c6400.h>
+
+#include <asm/io.h>
+#include <asm/errno.h>
+
+#define MAX_CHIPS	2
+static int nand_cs[MAX_CHIPS] = {0, 1};
+
+#ifdef CONFIG_NAND_SPL
+#define printf(arg...) do {} while (0)
+#endif
+
+/* Nand flash definition values by jsgood */
+#ifdef S3C_NAND_DEBUG
+/*
+ * Function to print out oob buffer for debugging
+ * Written by jsgood
+ */
+static void print_oob(const char *header, struct mtd_info *mtd)
+{
+	int i;
+	struct nand_chip *chip = mtd->priv;
+
+	printf("%s:\t", header);
+
+	for (i = 0; i < 64; i++)
+		printf("%02x ", chip->oob_poi[i]);
+
+	printf("\n");
+}
+#endif /* S3C_NAND_DEBUG */
+
+#ifdef CONFIG_NAND_SPL
+static u_char nand_read_byte(struct mtd_info *mtd)
+{
+	struct nand_chip *this = mtd->priv;
+	return readb(this->IO_ADDR_R);
+}
+
+static void nand_write_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
+{
+	int i;
+	struct nand_chip *this = mtd->priv;
+
+	for (i = 0; i < len; i++)
+		writeb(buf[i], this->IO_ADDR_W);
+}
+
+static void nand_read_buf(struct mtd_info *mtd, u_char *buf, int len)
+{
+	int i;
+	struct nand_chip *this = mtd->priv;
+
+	for (i = 0; i < len; i++)
+		buf[i] = readb(this->IO_ADDR_R);
+}
+#endif
+
+static void s3c_nand_select_chip(struct mtd_info *mtd, int chip)
+{
+	int ctrl = readl(NFCONT);
+
+	switch (chip) {
+	case -1:
+		ctrl |= 6;
+		break;
+	case 0:
+		ctrl &= ~2;
+		break;
+	case 1:
+		ctrl &= ~4;
+		break;
+	default:
+		return;
+	}
+
+	writel(ctrl, NFCONT);
+}
+
+/*
+ * Hardware specific access to control-lines function
+ * Written by jsgood
+ */
+static void s3c_nand_hwcontrol(struct mtd_info *mtd, int cmd, unsigned int ctrl)
+{
+	struct nand_chip *this = mtd->priv;
+
+	if (ctrl & NAND_CTRL_CHANGE) {
+		if (ctrl & NAND_CLE)
+			this->IO_ADDR_W = (void __iomem *)NFCMMD;
+		else if (ctrl & NAND_ALE)
+			this->IO_ADDR_W = (void __iomem *)NFADDR;
+		else
+			this->IO_ADDR_W = (void __iomem *)NFDATA;
+		if (ctrl & NAND_NCE)
+			s3c_nand_select_chip(mtd, *(int *)this->priv);
+		else
+			s3c_nand_select_chip(mtd, -1);
+	}
+
+	if (cmd != NAND_CMD_NONE)
+		writeb(cmd, this->IO_ADDR_W);
+}
+
+/*
+ * Function for checking device ready pin
+ * Written by jsgood
+ */
+static int s3c_nand_device_ready(struct mtd_info *mtdinfo)
+{
+	return !!(readl(NFSTAT) & NFSTAT_RnB);
+}
+
+#ifdef CFG_S3C_NAND_HWECC
+/*
+ * This function is called before encoding ecc codes to ready ecc engine.
+ * Written by jsgood
+ */
+static void s3c_nand_enable_hwecc(struct mtd_info *mtd, int mode)
+{
+	u_long nfcont, nfconf;
+
+	/*
+	 * The original driver used 4-bit ECC for "new" MLC chips, i.e., for
+	 * those with non-zero ID[3][3:2], which anyway only holds for ST
+	 * (Numonyx) chips
+	 */
+	nfconf = readl(NFCONF) & ~NFCONF_ECC_4BIT;
+
+	writel(nfconf, NFCONF);
+
+	/* Initialize & unlock */
+	nfcont = readl(NFCONT);
+	nfcont |= NFCONT_INITECC;
+	nfcont &= ~NFCONT_MECCLOCK;
+
+	if (mode == NAND_ECC_WRITE)
+		nfcont |= NFCONT_ECC_ENC;
+	else if (mode == NAND_ECC_READ)
+		nfcont &= ~NFCONT_ECC_ENC;
+
+	writel(nfcont, NFCONT);
+}
+
+/*
+ * This function is called immediately after encoding ecc codes.
+ * This function returns encoded ecc codes.
+ * Written by jsgood
+ */
+static int s3c_nand_calculate_ecc(struct mtd_info *mtd, const u_char *dat,
+				  u_char *ecc_code)
+{
+	u_long nfcont, nfmecc0;
+
+	/* Lock */
+	nfcont = readl(NFCONT);
+	nfcont |= NFCONT_MECCLOCK;
+	writel(nfcont, NFCONT);
+
+	nfmecc0 = readl(NFMECC0);
+
+	ecc_code[0] = nfmecc0 & 0xff;
+	ecc_code[1] = (nfmecc0 >> 8) & 0xff;
+	ecc_code[2] = (nfmecc0 >> 16) & 0xff;
+	ecc_code[3] = (nfmecc0 >> 24) & 0xff;
+
+	return 0;
+}
+
+/*
+ * This function determines whether read data is good or not.
+ * If SLC, must write ecc codes to controller before reading status bit.
+ * If MLC, status bit is already set, so only reading is needed.
+ * If status bit is good, return 0.
+ * If correctable errors occured, do that.
+ * If uncorrectable errors occured, return -1.
+ * Written by jsgood
+ */
+static int s3c_nand_correct_data(struct mtd_info *mtd, u_char *dat,
+				 u_char *read_ecc, u_char *calc_ecc)
+{
+	int ret = -1;
+	u_long nfestat0, nfmeccdata0, nfmeccdata1, err_byte_addr;
+	u_char err_type, repaired;
+
+	/* SLC: Write ecc to compare */
+	nfmeccdata0 = (calc_ecc[1] << 16) | calc_ecc[0];
+	nfmeccdata1 = (calc_ecc[3] << 16) | calc_ecc[2];
+	writel(nfmeccdata0, NFMECCDATA0);
+	writel(nfmeccdata1, NFMECCDATA1);
+
+	/* Read ecc status */
+	nfestat0 = readl(NFESTAT0);
+	err_type = nfestat0 & 0x3;
+
+	switch (err_type) {
+	case 0: /* No error */
+		ret = 0;
+		break;
+
+	case 1:
+		/*
+		 * 1 bit error (Correctable)
+		 * (nfestat0 >> 7) & 0x7ff	:error byte number
+		 * (nfestat0 >> 4) & 0x7	:error bit number
+		 */
+		err_byte_addr = (nfestat0 >> 7) & 0x7ff;
+		repaired = dat[err_byte_addr] ^ (1 << ((nfestat0 >> 4) & 0x7));
+
+		printf("S3C NAND: 1 bit error detected at byte %ld. "
+		       "Correcting from 0x%02x to 0x%02x...OK\n",
+		       err_byte_addr, dat[err_byte_addr], repaired);
+
+		dat[err_byte_addr] = repaired;
+
+		ret = 1;
+		break;
+
+	case 2: /* Multiple error */
+	case 3: /* ECC area error */
+		printf("S3C NAND: ECC uncorrectable error detected. "
+		       "Not correctable.\n");
+		ret = -1;
+		break;
+	}
+
+	return ret;
+}
+#endif /* CFG_S3C_NAND_HWECC */
+
+/*
+ * Board-specific NAND initialization. The following members of the
+ * argument are board-specific (per include/linux/mtd/nand.h):
+ * - IO_ADDR_R?: address to read the 8 I/O lines of the flash device
+ * - IO_ADDR_W?: address to write the 8 I/O lines of the flash device
+ * - hwcontrol: hardwarespecific function for accesing control-lines
+ * - dev_ready: hardwarespecific function for  accesing device ready/busy line
+ * - enable_hwecc?: function to enable (reset)  hardware ecc generator. Must
+ *   only be provided if a hardware ECC is available
+ * - eccmode: mode of ecc, see defines
+ * - chip_delay: chip dependent delay for transfering data from array to
+ *   read regs (tR)
+ * - options: various chip options. They can partly be set to inform
+ *   nand_scan about special functionality. See the defines for further
+ *   explanation
+ * Members with a "?" were not set in the merged testing-NAND branch,
+ * so they are not set here either.
+ */
+int board_nand_init(struct nand_chip *nand)
+{
+	static int chip_n;
+
+	if (chip_n >= MAX_CHIPS)
+		return -ENODEV;
+
+	NFCONT_REG = (NFCONT_REG & ~NFCONT_WP) | NFCONT_ENABLE | 0x6;
+
+	nand->IO_ADDR_R		= (void __iomem *)NFDATA;
+	nand->IO_ADDR_W		= (void __iomem *)NFDATA;
+	nand->cmd_ctrl		= s3c_nand_hwcontrol;
+	nand->dev_ready		= s3c_nand_device_ready;
+	nand->select_chip	= s3c_nand_select_chip;
+	nand->options		= 0;
+#ifdef CONFIG_NAND_SPL
+	nand->read_byte		= nand_read_byte;
+	nand->write_buf		= nand_write_buf;
+	nand->read_buf		= nand_read_buf;
+#endif
+
+#ifdef CFG_S3C_NAND_HWECC
+	nand->ecc.hwctl		= s3c_nand_enable_hwecc;
+	nand->ecc.calculate	= s3c_nand_calculate_ecc;
+	nand->ecc.correct	= s3c_nand_correct_data;
+
+	/*
+	 * If you get more than 1 NAND-chip with different page-sizes on the
+	 * board one day, it will get more complicated...
+	 */
+	nand->ecc.mode		= NAND_ECC_HW;
+	nand->ecc.size		= CFG_NAND_ECCSIZE;
+	nand->ecc.bytes		= CFG_NAND_ECCBYTES;
+#else
+	nand->ecc.mode		= NAND_ECC_SOFT;
+#endif /* ! CFG_S3C_NAND_HWECC */
+
+	nand->priv		= nand_cs + chip_n++;
+
+	return 0;
+}