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/*
* (C) Copyright 2006-2008
* 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; }
static int nand_ecc_pos[] = CFG_NAND_ECCPOS;
extern void board_nand_init(struct nand_chip *nand);
#if (CFG_NAND_PAGE_SIZE <= 512)
/*
* NAND command for small page NAND devices (512)
*/
static int nand_command(struct mtd_info *mtd, int block, int page, int offs, u8 cmd)
{
struct nand_chip *this = mtd->priv;
int page_addr = page + block * CFG_NAND_PAGE_COUNT;
if (this->dev_ready)
this->dev_ready(mtd);
else
CFG_NAND_READ_DELAY;
/* Begin command latch cycle */
this->hwcontrol(mtd, NAND_CTL_SETCLE);
this->write_byte(mtd, cmd);
/* 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, offs); /* 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;
return 0;
}
#else
/*
* NAND command for large page NAND devices (2k)
*/
static int nand_command(struct mtd_info *mtd, int block, int page, int offs, u8 cmd)
{
struct nand_chip *this = mtd->priv;
int page_offs = offs;
int page_addr = page + block * CFG_NAND_PAGE_COUNT;
if (this->dev_ready)
this->dev_ready(mtd);
else
CFG_NAND_READ_DELAY;
/* Emulate NAND_CMD_READOOB */
if (cmd == NAND_CMD_READOOB) {
page_offs += CFG_NAND_PAGE_SIZE;
cmd = NAND_CMD_READ0;
}
/* Begin command latch cycle */
this->hwcontrol(mtd, NAND_CTL_SETCLE);
this->write_byte(mtd, cmd);
/* 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, page_offs & 0xff); /* A[7:0] */
this->write_byte(mtd, (uchar)((page_offs >> 8) & 0xff)); /* A[11:9] */
/* Row address */
this->write_byte(mtd, (uchar)(page_addr & 0xff)); /* A[19:12] */
this->write_byte(mtd, (uchar)((page_addr >> 8) & 0xff)); /* A[27:20] */
#ifdef CFG_NAND_5_ADDR_CYCLE
/* One more address cycle for devices > 128MiB */
this->write_byte(mtd, (uchar)((page_addr >> 16) & 0x0f)); /* A[xx:28] */
#endif
/* Latch in address */
this->hwcontrol(mtd, NAND_CTL_CLRALE);
/* Begin command latch cycle */
this->hwcontrol(mtd, NAND_CTL_SETCLE);
/* Write out the start read command */
this->write_byte(mtd, NAND_CMD_READSTART);
/* End command latch cycle */
this->hwcontrol(mtd, NAND_CTL_CLRCLE);
/*
* Wait a while for the data to be ready
*/
if (this->dev_ready)
this->dev_ready(mtd);
else
CFG_NAND_READ_DELAY;
return 0;
}
#endif
static int nand_is_bad_block(struct mtd_info *mtd, int block)
{
struct nand_chip *this = mtd->priv;
nand_command(mtd, block, 0, CFG_NAND_BAD_BLOCK_POS, NAND_CMD_READOOB);
/*
* Read one 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;
u_char *ecc_calc;
u_char *ecc_code;
u_char *oob_data;
int i;
int eccsize = CFG_NAND_ECCSIZE;
int eccbytes = CFG_NAND_ECCBYTES;
int eccsteps = CFG_NAND_ECCSTEPS;
uint8_t *p = dst;
int stat;
nand_command(mtd, block, page, 0, NAND_CMD_READ0);
/* No malloc available for now, just use some temporary locations
* in SDRAM
*/
ecc_calc = (u_char *)(CFG_SDRAM_BASE + 0x10000);
ecc_code = ecc_calc + 0x100;
oob_data = ecc_calc + 0x200;
for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
this->enable_hwecc(mtd, NAND_ECC_READ);
this->read_buf(mtd, p, eccsize);
this->calculate_ecc(mtd, p, &ecc_calc[i]);
}
this->read_buf(mtd, oob_data, CFG_NAND_OOBSIZE);
/* Pick the ECC bytes out of the oob data */
for (i = 0; i < CFG_NAND_ECCTOTAL; i++)
ecc_code[i] = oob_data[nand_ecc_pos[i]];
eccsteps = CFG_NAND_ECCSTEPS;
p = dst;
for (i = 0 ; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
/* No chance to do something with the possible error message
* from correct_data(). We just hope that all possible errors
* are corrected by this routine.
*/
stat = this->correct_data(mtd, p, &ecc_code[i], &ecc_calc[i]);
}
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)();
}