diff options
Diffstat (limited to 'u-boot/board/prodrive/pdnb3/nand.c')
| -rw-r--r-- | u-boot/board/prodrive/pdnb3/nand.c | 155 |
1 files changed, 155 insertions, 0 deletions
diff --git a/u-boot/board/prodrive/pdnb3/nand.c b/u-boot/board/prodrive/pdnb3/nand.c new file mode 100644 index 0000000..2efe027 --- /dev/null +++ b/u-boot/board/prodrive/pdnb3/nand.c @@ -0,0 +1,155 @@ +/* + * (C) Copyright 2006 + * Stefan Roese, DENX Software Engineering, sr@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> + +#if defined(CONFIG_CMD_NAND) + +#include <nand.h> + +struct pdnb3_ndfc_regs { + uchar cmd; + uchar wait; + uchar addr; + uchar term; + uchar data; +}; + +static u8 hwctl; +static struct pdnb3_ndfc_regs *pdnb3_ndfc; + +#define readb(addr) *(volatile u_char *)(addr) +#define readl(addr) *(volatile u_long *)(addr) +#define writeb(d,addr) *(volatile u_char *)(addr) = (d) + +/* + * The PDNB3 has a NAND Flash Controller (NDFC) that handles all accesses to + * the NAND devices. The NDFC has command, address and data registers that + * when accessed will set up the NAND flash pins appropriately. We'll use the + * hwcontrol function to save the configuration in a global variable. + * We can then use this information in the read and write functions to + * determine which NDFC register to access. + * + * There is one NAND devices on the board, a Hynix HY27US08561A (32 MByte). + */ +static void pdnb3_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 ) + hwctl |= 0x1; + else + hwctl &= ~0x1; + if ( ctrl & NAND_ALE ) + hwctl |= 0x2; + else + hwctl &= ~0x2; + if ( (ctrl & NAND_NCE) != NAND_NCE) + writeb(0x00, &(pdnb3_ndfc->term)); + } + if (cmd != NAND_CMD_NONE) + writeb(cmd, this->IO_ADDR_W); +} + + +static u_char pdnb3_nand_read_byte(struct mtd_info *mtd) +{ + return readb(&(pdnb3_ndfc->data)); +} + +static void pdnb3_nand_write_buf(struct mtd_info *mtd, const u_char *buf, int len) +{ + int i; + + for (i = 0; i < len; i++) { + if (hwctl & 0x1) + writeb(buf[i], &(pdnb3_ndfc->cmd)); + else if (hwctl & 0x2) + writeb(buf[i], &(pdnb3_ndfc->addr)); + else + writeb(buf[i], &(pdnb3_ndfc->data)); + } +} + +static void pdnb3_nand_read_buf(struct mtd_info *mtd, u_char *buf, int len) +{ + int i; + + if (len % 4) { + for (i = 0; i < len; i++) + buf[i] = readb(&(pdnb3_ndfc->data)); + } else { + ulong *ptr = (ulong *)buf; + int count = len >> 2; + + for (i = 0; i < count; i++) + *ptr++ = readl(&(pdnb3_ndfc->data)); + } +} + +static int pdnb3_nand_verify_buf(struct mtd_info *mtd, const u_char *buf, int len) +{ + int i; + + for (i = 0; i < len; i++) + if (buf[i] != readb(&(pdnb3_ndfc->data))) + return i; + + return 0; +} + +static int pdnb3_nand_dev_ready(struct mtd_info *mtd) +{ + volatile u_char val; + + /* + * Blocking read to wait for NAND to be ready + */ + val = readb(&(pdnb3_ndfc->wait)); + + /* + * Return always true + */ + return 1; +} + +int board_nand_init(struct nand_chip *nand) +{ + pdnb3_ndfc = (struct pdnb3_ndfc_regs *)CONFIG_SYS_NAND_BASE; + + nand->ecc.mode = NAND_ECC_SOFT; + + /* Set address of NAND IO lines (Using Linear Data Access Region) */ + nand->IO_ADDR_R = (void __iomem *) ((ulong) pdnb3_ndfc + 0x4); + nand->IO_ADDR_W = (void __iomem *) ((ulong) pdnb3_ndfc + 0x4); + /* Reference hardware control function */ + nand->cmd_ctrl = pdnb3_nand_hwcontrol; + nand->read_byte = pdnb3_nand_read_byte; + nand->write_buf = pdnb3_nand_write_buf; + nand->read_buf = pdnb3_nand_read_buf; + nand->verify_buf = pdnb3_nand_verify_buf; + nand->dev_ready = pdnb3_nand_dev_ready; + return 0; +} +#endif |