u-boot/nand_spl/nand_boot.c
2006-10-09 00:42:01 +02:00

177 lines
4.6 KiB
C

/*
* (C) Copyright 2006
* Stefan Roese, DENX Software Engineering, sr@denx.de.
*
* 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>
#define CFG_NAND_READ_DELAY \
{ volatile int dummy; int i; for (i=0; i<10000; i++) dummy = i; }
extern void board_nand_init(struct nand_chip *nand);
extern void ndfc_hwcontrol(struct mtd_info *mtdinfo, int cmd);
extern void ndfc_write_byte(struct mtd_info *mtdinfo, u_char byte);
extern u_char ndfc_read_byte(struct mtd_info *mtdinfo);
extern int ndfc_dev_ready(struct mtd_info *mtdinfo);
extern int jump_to_ram(ulong delta);
extern int jump_to_uboot(ulong addr);
static int nand_is_bad_block(struct mtd_info *mtd, int block)
{
struct nand_chip *this = mtd->priv;
int page_addr = block * CFG_NAND_PAGE_COUNT;
/* Begin command latch cycle */
this->hwcontrol(mtd, NAND_CTL_SETCLE);
this->write_byte(mtd, NAND_CMD_READOOB);
/* Set ALE and clear CLE to start address cycle */
this->hwcontrol(mtd, NAND_CTL_CLRCLE);
this->hwcontrol(mtd, NAND_CTL_SETALE);
/* Column address */
this->write_byte(mtd, CFG_NAND_BAD_BLOCK_POS); /* A[7:0] */
this->write_byte(mtd, (uchar)(page_addr & 0xff)); /* A[16:9] */
this->write_byte(mtd, (uchar)((page_addr >> 8) & 0xff)); /* A[24:17] */
#ifdef CFG_NAND_4_ADDR_CYCLE
/* One more address cycle for devices > 32MiB */
this->write_byte(mtd, (uchar)((page_addr >> 16) & 0x0f)); /* A[xx:25] */
#endif
/* Latch in address */
this->hwcontrol(mtd, NAND_CTL_CLRALE);
/*
* Wait a while for the data to be ready
*/
if (this->dev_ready)
this->dev_ready(mtd);
else
CFG_NAND_READ_DELAY;
/*
* Read on byte
*/
if (this->read_byte(mtd) != 0xff)
return 1;
return 0;
}
static int nand_read_page(struct mtd_info *mtd, int block, int page, uchar *dst)
{
struct nand_chip *this = mtd->priv;
int page_addr = page + block * CFG_NAND_PAGE_COUNT;
int i;
/* Begin command latch cycle */
this->hwcontrol(mtd, NAND_CTL_SETCLE);
this->write_byte(mtd, NAND_CMD_READ0);
/* Set ALE and clear CLE to start address cycle */
this->hwcontrol(mtd, NAND_CTL_CLRCLE);
this->hwcontrol(mtd, NAND_CTL_SETALE);
/* Column address */
this->write_byte(mtd, 0); /* A[7:0] */
this->write_byte(mtd, (uchar)(page_addr & 0xff)); /* A[16:9] */
this->write_byte(mtd, (uchar)((page_addr >> 8) & 0xff)); /* A[24:17] */
#ifdef CFG_NAND_4_ADDR_CYCLE
/* One more address cycle for devices > 32MiB */
this->write_byte(mtd, (uchar)((page_addr >> 16) & 0x0f)); /* A[xx:25] */
#endif
/* Latch in address */
this->hwcontrol(mtd, NAND_CTL_CLRALE);
/*
* Wait a while for the data to be ready
*/
if (this->dev_ready)
this->dev_ready(mtd);
else
CFG_NAND_READ_DELAY;
/*
* Read page into buffer
*/
for (i=0; i<CFG_NAND_PAGE_SIZE; i++)
*dst++ = this->read_byte(mtd);
return 0;
}
static int nand_load(struct mtd_info *mtd, int offs, int uboot_size, uchar *dst)
{
int block;
int blockcopy_count;
int page;
/*
* offs has to be aligned to a block address!
*/
block = offs / CFG_NAND_BLOCK_SIZE;
blockcopy_count = 0;
while (blockcopy_count < (uboot_size / CFG_NAND_BLOCK_SIZE)) {
if (!nand_is_bad_block(mtd, block)) {
/*
* Skip bad blocks
*/
for (page = 0; page < CFG_NAND_PAGE_COUNT; page++) {
nand_read_page(mtd, block, page, dst);
dst += CFG_NAND_PAGE_SIZE;
}
blockcopy_count++;
}
block++;
}
return 0;
}
void nand_boot(void)
{
ulong mem_size;
struct nand_chip nand_chip;
nand_info_t nand_info;
int ret;
void (*uboot)(void);
/*
* Init sdram, so we have access to memory
*/
mem_size = initdram(0);
/*
* Init board specific nand support
*/
nand_info.priv = &nand_chip;
nand_chip.IO_ADDR_R = nand_chip.IO_ADDR_W = (void __iomem *)CFG_NAND_BASE;
nand_chip.dev_ready = NULL; /* preset to NULL */
board_nand_init(&nand_chip);
/*
* Load U-Boot image from NAND into RAM
*/
ret = nand_load(&nand_info, CFG_NAND_U_BOOT_OFFS, CFG_NAND_U_BOOT_SIZE,
(uchar *)CFG_NAND_U_BOOT_DST);
/*
* Jump to U-Boot image
*/
uboot = (void (*)(void))CFG_NAND_U_BOOT_START;
(*uboot)();
}