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Diffstat (limited to 'board/socrates/nand.c')
| -rw-r--r-- | board/socrates/nand.c | 218 | 
1 files changed, 218 insertions, 0 deletions
| diff --git a/board/socrates/nand.c b/board/socrates/nand.c new file mode 100644 index 000000000..fc82ecbb7 --- /dev/null +++ b/board/socrates/nand.c @@ -0,0 +1,218 @@ +/* + * (C) Copyright 2008 + * Sergei Poselenov, Emcraft Systems, sposelenov@emcraft.com. + * + * 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> + +#if defined(CFG_NAND_BASE) +#include <nand.h> +#include <asm/errno.h> +#include <asm/io.h> + +static int state; +static void nand_write_byte(struct mtd_info *mtd, u_char byte); +static void nand_write_buf(struct mtd_info *mtd, const u_char *buf, int len); +static void nand_write_word(struct mtd_info *mtd, u16 word); +static u_char nand_read_byte(struct mtd_info *mtd); +static u16 nand_read_word(struct mtd_info *mtd); +static void nand_read_buf(struct mtd_info *mtd, u_char *buf, int len); +static int nand_verify_buf(struct mtd_info *mtd, const u_char *buf, int len); +static int nand_device_ready(struct mtd_info *mtdinfo); +static void nand_hwcontrol(struct mtd_info *mtdinfo, int cmd); + +#define FPGA_NAND_CMD_MASK		(0x7 << 28) +#define FPGA_NAND_CMD_COMMAND	(0x0 << 28) +#define FPGA_NAND_CMD_ADDR		(0x1 << 28) +#define FPGA_NAND_CMD_READ		(0x2 << 28) +#define FPGA_NAND_CMD_WRITE		(0x3 << 28) +#define FPGA_NAND_BUSY			(0x1 << 15) +#define FPGA_NAND_ENABLE		(0x1 << 31) +#define FPGA_NAND_DATA_SHIFT	16 + +/** + * nand_write_byte -  write one byte to the chip + * @mtd:	MTD device structure + * @byte:	pointer to data byte to write + */ +static void nand_write_byte(struct mtd_info *mtd, u_char byte) +{ +	nand_write_buf(mtd, (const uchar *)&byte, sizeof(byte)); +} + +/** + * nand_write_word -  write one word to the chip + * @mtd:	MTD device structure + * @word:	data word to write + */ +static void nand_write_word(struct mtd_info *mtd, u16 word) +{ +	nand_write_buf(mtd, (const uchar *)&word, sizeof(word)); +} + +/** + * nand_write_buf -  write buffer to chip + * @mtd:	MTD device structure + * @buf:	data buffer + * @len:	number of bytes to write + */ +static void nand_write_buf(struct mtd_info *mtd, const u_char *buf, int len) +{ +	int i; +	struct nand_chip *this = mtd->priv; +	long val; + +	if ((state & FPGA_NAND_CMD_MASK) == FPGA_NAND_CMD_MASK) { +		/* Write data */ +		val = (state & FPGA_NAND_ENABLE) | FPGA_NAND_CMD_WRITE; +	} else { +		/* Write address or command */ +		val = state; +	} + +	for (i = 0; i < len; i++) { +		out_be32(this->IO_ADDR_W, val | (buf[i] << FPGA_NAND_DATA_SHIFT)); +	} +} + + +/** + * nand_read_byte -  read one byte from the chip + * @mtd:	MTD device structure + */ +static u_char nand_read_byte(struct mtd_info *mtd) +{ +	u8 byte; +	nand_read_buf(mtd, (uchar *)&byte, sizeof(byte)); +	return byte; +} + +/** + * nand_read_word -  read one word from the chip + * @mtd:	MTD device structure + */ +static u16 nand_read_word(struct mtd_info *mtd) +{ +	u16 word; +	nand_read_buf(mtd, (uchar *)&word, sizeof(word)); +	return word; +} + +/** + * nand_read_buf -  read chip data into buffer + * @mtd:	MTD device structure + * @buf:	buffer to store date + * @len:	number of bytes to read + */ +static void nand_read_buf(struct mtd_info *mtd, u_char *buf, int len) +{ +	int i; +	struct nand_chip *this = mtd->priv; +	int val; + +	val = (state & FPGA_NAND_ENABLE) | FPGA_NAND_CMD_READ; + +	out_be32(this->IO_ADDR_W, val); +	for (i = 0; i < len; i++) { +		buf[i] = (in_be32(this->IO_ADDR_R) >> FPGA_NAND_DATA_SHIFT) & 0xff; +	} +} + +/** + * nand_verify_buf -  Verify chip data against buffer + * @mtd:	MTD device structure + * @buf:	buffer containing the data to compare + * @len:	number of bytes to compare + */ +static int nand_verify_buf(struct mtd_info *mtd, const u_char *buf, int len) +{ +	int i; + +	for (i = 0; i < len; i++) { +		if (buf[i] != nand_read_byte(mtd)); +		return -EFAULT; +	} +	return 0; +} + +/** + * nand_device_ready - Check the NAND device is ready for next command. + * @mtd:	MTD device structure + */ +static int nand_device_ready(struct mtd_info *mtdinfo) +{ +	struct nand_chip *this = mtdinfo->priv; + +	if (in_be32(this->IO_ADDR_W) & FPGA_NAND_BUSY) +		return 0; /* busy */ +	return 1; +} + +/** + * nand_hwcontrol - NAND control functions wrapper. + * @mtd:	MTD device structure + * @cmd:	Command + */ +static void nand_hwcontrol(struct mtd_info *mtdinfo, int cmd) +{ + +	switch(cmd) { +	case NAND_CTL_CLRALE: +		state |= FPGA_NAND_CMD_MASK; /* use all 1s to mark */ +		break; +	case NAND_CTL_CLRCLE: +		state |= FPGA_NAND_CMD_MASK; /* use all 1s to mark */ +		break; +	case NAND_CTL_SETCLE: +		state = (state & ~FPGA_NAND_CMD_MASK) | FPGA_NAND_CMD_COMMAND; +		break; +	case NAND_CTL_SETALE: +		state = (state & ~FPGA_NAND_CMD_MASK) | FPGA_NAND_CMD_ADDR; +		break; +	case NAND_CTL_SETNCE: +		state |= FPGA_NAND_ENABLE; +		break; +	case NAND_CTL_CLRNCE: +		state &= ~FPGA_NAND_ENABLE; +		break; +	default: +		printf("%s: unknown cmd %#x\n", __FUNCTION__, cmd); +		break; +	} +} + +int board_nand_init(struct nand_chip *nand) +{ +	nand->hwcontrol = nand_hwcontrol; +	nand->eccmode = NAND_ECC_SOFT; +	nand->dev_ready = nand_device_ready; +	nand->write_byte = nand_write_byte; +	nand->read_byte = nand_read_byte; +	nand->write_word = nand_write_word; +	nand->read_word = nand_read_word; +	nand->write_buf = nand_write_buf; +	nand->read_buf = nand_read_buf; +	nand->verify_buf = nand_verify_buf; + +	return 0; +} + +#endif |