s3c2440 nand flash 的操作

and_reset(void)
{
s3c2410_nand_select_chip();
s3c2410_write_cmd(0xff); // 复位命令
s3c2410_wait_idle();
s3c2410_nand_deselect_chip();
}

static void s3c2410_wait_idle(void)
{
int i;
volatile unsigned char *p = (volatile unsigned char *)&s3c2410nand->NFSTAT;
while(!(*p & BUSY))
for(i=0; i<10; i++);
}

static void s3c2410_nand_select_chip(void)
{
int i;
s3c2410nand->NFCONF &= ~(1<11);
for(i=0; i<10; i++);
}

static void s3c2410_nand_deselect_chip(void)
{
s3c2410nand->NFCONF |= (1<11);
}

static void s3c2410_write_cmd(int cmd)
{
volatile unsigned char *p = (volatile unsigned char *)&s3c2410nand->NFCMD;
*p = cmd;
}

static void s3c2410_write_addr(unsigned int addr)
{
int i;
volatile unsigned char *p = (volatile unsigned char *)&s3c2410nand->NFADDR;

*p = addr & 0xff;
for(i=0; i<10; i++);
*p = (addr >> 9) & 0xff;
for(i=0; i<10; i++);
*p = (addr >> 17) & 0xff;
for(i=0; i<10; i++);
*p = (addr >> 25) & 0xff;
for(i=0; i<10; i++);
}

static unsigned char s3c2410_read_data(void)
{
volatile unsigned char *p = (volatile unsigned char *)&s3c2410nand->NFDATA;
return *p;
}

static void s3c2440_nand_reset(void)
{
s3c2440_nand_select_chip();
s3c2440_write_cmd(0xff); // 复位命令
s3c2440_wait_idle();
s3c2440_nand_deselect_chip();
}

static void s3c2440_wait_idle(void)
{
int i;
volatile unsigned char *p = (volatile unsigned char *)&s3c2440nand->NFSTAT;
while(!(*p & BUSY))
for(i=0; i<10; i++);
}

static void s3c2440_nand_select_chip(void)
{
int i;
s3c2440nand->NFCONT &= ~(1<1);
for(i=0; i<10; i++);
}

static void s3c2440_nand_deselect_chip(void)
{
s3c2440nand->NFCONT |= (1<1);
}

static void s3c2440_write_cmd(int cmd)
{
volatile unsigned char *p = (volatile unsigned char *)&s3c2440nand->NFCMD;
*p = cmd;
}

static void s3c2440_write_addr(unsigned int addr)
{
int i;
volatile unsigned char *p = (volatile unsigned char *)&s3c2440nand->NFADDR;

*p = addr & 0xff;
for(i=0; i<10; i++);
*p = (addr >> 9) & 0xff;
for(i=0; i<10; i++);
*p = (addr >> 17) & 0xff;
for(i=0; i<10; i++);
*p = (addr >> 25) & 0xff;
for(i=0; i<10; i++);
}

static unsigned char s3c2440_read_data(void)
{
volatile unsigned char *p = (volatile unsigned char *)&s3c2440nand->NFDATA;
return *p;
}

static void nand_reset(void)
{
nand_chip.nand_reset();
}

static void wait_idle(void)
{
nand_chip.wait_idle();
}

static void nand_select_chip(void)
{
int i;
nand_chip.nand_select_chip();
for(i=0; i<10; i++);
}

static void nand_deselect_chip(void)
{
nand_chip.nand_deselect_chip();
}

static void write_cmd(int cmd)
{
nand_chip.write_cmd(cmd);
}
static void write_addr(unsigned int addr)
{
nand_chip.write_addr(addr);
}

static unsigned char read_data(void)
{
return nand_chip.read_data();
}

void nand_init(void)
{
#define TACLS 0
#define TWRPH0 3
#define TWRPH1 0

if ((GSTATUS1 == 0x32410000) || (GSTATUS1 == 0x32410002))
{
nand_chip.nand_reset = s3c2410_nand_reset;
nand_chip.wait_idle = s3c2410_wait_idle;
nand_chip.nand_select_chip = s3c2410_nand_select_chip;
nand_chip.nand_deselect_chip = s3c2410_nand_deselect_chip;
nand_chip.write_cmd = s3c2410_write_cmd;
nand_chip.write_addr = s3c2410_write_addr;
nand_chip.read_data = s3c2410_read_data;

s3c2410nand->NFCONF = (1<15)|(1<12)|(1<11)|(TACLS<8)|(TWRPH0<4)|(TWRPH1<0);
}
else
{
nand_chip.nand_reset = s3c2440_nand_reset;
nand_chip.wait_idle = s3c2440_wait_idle;
nand_chip.nand_select_chip = s3c2440_nand_select_chip;
nand_chip.nand_deselect_chip = s3c2440_nand_deselect_chip;
nand_chip.write_cmd = s3c2440_write_cmd;
nand_chip.write_addr = s3c2440_write_addr;
nand_chip.read_data = s3c2440_read_data;

s3c2440nand->NFCONF = (TACLS<12)|(TWRPH0<8)|(TWRPH1<4);

s3c2440nand->NFCONT = (1<4)|(1<1)|(1<0);
}


nand_reset();
}

#define NAND_SECTOR_SIZE 512
#define NAND_BLOCK_MASK (NAND_SECTOR_SIZE - 1)

void nand_read(unsigned char *buf, unsigned long start_addr, int size)
{
int i, j;

if ((start_addr & NAND_BLOCK_MASK) || (size & NAND_BLOCK_MASK)) {
return ;
}

nand_select_chip();

for(i=start_addr; i < (start_addr + size);) {

write_cmd(0);