@ File：head.s
@ 功能：設(shè)置SDRAM，將程序復(fù)制到SDRAM，然后跳到SDRAM繼續(xù)執(zhí)行
@******************************************************************************

.text
.global _start
_start:
@函數(shù)disable_watch_dog, memsetup, init_nand, nand_read_ll在init.c中定義
ldr sp, =4096 @設(shè)置堆棧
bl disable_watch_dog @關(guān)WATCH DOG
bl memsetup @初始化SDRAM
bl nand_init @初始化NAND Flash

@將NAND Flash中地址4096開(kāi)始的1024字節(jié)代碼(main.c編譯得到)復(fù)制到SDRAM中
@nand_read_ll函數(shù)需要3個(gè)參數(shù)：
ldr r0, =0x30000000 @1. 目標(biāo)地址=0x30000000，這是SDRAM的起始地址
mov r1, #4096 @2. 源地址 = 4096，連接的時(shí)候，main.c中的代碼都存在NAND Flash地址4096開(kāi)始處
mov r2, #1024 @3. 復(fù)制長(zhǎng)度= 1024(bytes)，對(duì)于本實(shí)驗(yàn)的main.c，這是足夠了
bl nand_read @調(diào)用C函數(shù)nand_read

ldr sp, =0x34000000 @設(shè)置棧
ldr lr, =halt_loop @設(shè)置返回地址
ldr pc, =main @b指令和bl指令只能前后跳轉(zhuǎn)32M的范圍，所以這里使用向pc賦值的方法進(jìn)行跳轉(zhuǎn)
halt_loop:
b halt_loop

#define WTCON(*(volatile unsigned long *)0x53000000)

#define MEM_CTL_BASE0x48000000

void disable_watch_dog();
void memsetup();

void disable_watch_dog()
{
WTCON= 0;
}

void memsetup()
{
int i = 0;
unsigned long *p = (unsigned long *)MEM_CTL_BASE;

unsigned long const mem_cfg_val[]={ 0x22011110, //BWSCON
0x00000700, //BANKCON0
0x00000700, //BANKCON1
0x00000700, //BANKCON2
0x00000700, //BANKCON3
0x00000700, //BANKCON4
0x00000700, //BANKCON5
0x00018005, //BANKCON6
0x00018005, //BANKCON7
0x008C07A3, //REFRESH
0x000000B1, //BANKSIZE
0x00000030, //MRSRB6
0x00000030, //MRSRB7
};

for(; i < 13; i++)
p[i] = mem_cfg_val[i];
}

ｎａｎｄ．ｃ

#define GSTATUS1 (*(volatile unsigned int *)0x560000B0)
#define BUSY 1

typedef unsigned int S3C24X0_REG32;

typedef struct {
S3C24X0_REG32 NFCONF;
S3C24X0_REG32 NFCMD;
S3C24X0_REG32 NFADDR;
S3C24X0_REG32 NFDATA;
S3C24X0_REG32 NFSTAT;
S3C24X0_REG32 NFECC;
} S3C2410_NAND;

typedef struct {
S3C24X0_REG32 NFCONF;
S3C24X0_REG32 NFCONT;
S3C24X0_REG32 NFCMD;
S3C24X0_REG32 NFADDR;
S3C24X0_REG32 NFDATA;
S3C24X0_REG32 NFMECCD0;
S3C24X0_REG32 NFMECCD1;
S3C24X0_REG32 NFSECCD;
S3C24X0_REG32 NFSTAT;
S3C24X0_REG32 NFESTAT0;
S3C24X0_REG32 NFESTAT1;
S3C24X0_REG32 NFMECC0;
S3C24X0_REG32 NFMECC1;
S3C24X0_REG32 NFSECC;
S3C24X0_REG32 NFSBLK;
S3C24X0_REG32 NFEBLK;
} S3C2440_NAND;

typedef struct {
void (*nand_reset)(void);
void (*wait_idle)(void);
void (*nand_select_chip)(void);
void (*nand_deselect_chip)(void);
void (*write_cmd)(int cmd);
void (*write_addr)(unsigned int addr);
unsigned char (*read_data)(void);
}t_nand_chip;

static S3C2410_NAND * s3c2410nand = (S3C2410_NAND *)0x4e000000;
static S3C2440_NAND * s3c2440nand = (S3C2440_NAND *)0x4e000000;

static t_nand_chip nand_chip;

void nand_init(void);
void nand_read(unsigned char *buf, unsigned long start_addr, int size);

static void nand_reset(void);
static void wait_idle(void);
static void nand_select_chip(void);
static void nand_deselect_chip(void);
static void write_cmd(int cmd);
static void write_addr(unsigned int addr);
static unsigned char read_data(void);

static void s3c2410_nand_reset(void);
static void s3c2410_wait_idle(void);
static void s3c2410_nand_select_chip(void);
static void s3c2410_nand_deselect_chip(void);
static void s3c2410_write_cmd(int cmd);
static void s3c2410_write_addr(unsigned int addr);
static unsigned char s3c2410_read_data();

static void s3c2440_nand_reset(void);
static void s3c2440_wait_idle(void);
static void s3c2440_nand_select_chip(void);
static void s3c2440_nand_deselect_chip(void);
static void s3c2440_write_cmd(int cmd);
static void s3c2440_write_addr(unsigned int addr);
static unsigned char s3c2440_read_data(void);

static void s3c2410_nand_reset(void)
{
s3c2410_nand_select_chip();
s3c2410_write_cmd(0xff); // 復(fù)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); // 復(fù)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);

write_addr(i);
wait_idle();

for(j=0; j < NAND_SECTOR_SIZE; j++, i++) {
*buf = read_data();
buf++;
}
}

nand_deselect_chip();

return ;
}

main 函數(shù)
#defineGPBCON(*(volatile unsigned long *)0x56000010)
#defineGPBDAT(*(volatile unsigned long *)0x56000014)

#defineGPB5_out(1<<(5*2))
#defineGPB6_out(1<<(6*2))
#defineGPB7_out(1<<(7*2))
#defineGPB8_out(1<<(8*2))

void wait(unsigned long dly)
{
for(; dly > 0; dly--);
}

int main(void)
{
unsigned long i = 0;

GPBCON = GPB5_out|GPB6_out|GPB7_out|GPB8_out;// 將LED1-4對(duì)應(yīng)的GPB5/6/7/8四個(gè)引腳設(shè)為輸出

while(1){
wait(30000);
GPBDAT = (~(i<<5)); // 根據(jù)i的值，點(diǎn)亮LED1-4
if(++i == 16)
i = 0;
}

return 0;
}