init.c

S3C2410 实验代码 对底层驱动程序开发有帮助

#include "s3c2410.h"

/* SDRAM 13个寄存器的值 */
unsigned long  const	mem_cfg_val[]={	0x22111110,		//BWSCON
				0x00000700,		//BANKCON0
				0x00000700,		//BANKCON1
				0x00000700,		//BANKCON2
				0x00000700,		//BANKCON3	
				0x00000700,		//BANKCON4
				0x00000700,		//BANKCON5
				0x00018005,		//BANKCON6
				0x00018005,		//BANKCON7
				0x008e07a3,		//REFRESH
				0x000000b2,		//BANKSIZE
				0x00000030,		//MRSRB6
				0x00000030,		//MRSRB7
				 };


 
void disable_watch_dog(void);
void memsetup(void);
void reset_nand(void);
void init_nand(void);
inline void wait_idle(void);
void nand_read_ll(unsigned char *buf, unsigned long start_addr, int size);

/*上电后，WATCH DOG默认是开着的，要把它关掉 */
void disable_watch_dog()
{
	WTCON	= 0;
}

/* 设置控制SDRAM的13个寄存器 */
void memsetup()
{
	int 	i = 0;
	unsigned long *p = (unsigned long *)MEM_CTL_BASE;
	for(; i < 13; i++)
		p[i] = mem_cfg_val[i];
}


/**************************************************************************   
* 设置控制SDRAM的13个寄存器
* 使用位置无关代码
**************************************************************************/   
void memsetup_2(void)
{
	unsigned long *p = (unsigned long *)MEM_CTL_BASE;	
	p[0] = 0x22111110;		//BWSCON
	p[1] = 0x00000700;		//BANKCON0
	p[2] = 0x00000700;		//BANKCON1
	p[3] = 0x00000700;		//BANKCON2
	p[4] = 0x00000700;		//BANKCON3	
	p[5] = 0x00000700;		//BANKCON4
	p[6] = 0x00000700;		//BANKCON5
	p[7] = 0x00018005;		//BANKCON6
	p[8] = 0x00018005;		//BANKCON7
	p[9] = 0x008e07a3;		//REFRESH,HCLK=12MHz:0x008e07a3,HCLK=100MHz:0x008e04f4
	p[10] = 0x000000b2;		//BANKSIZE
	p[11] = 0x00000030;		//MRSRB6
	p[12] = 0x00000030;		//MRSRB7
}


/* 在第一次实用NAND Flash前，复位一下NAND Flash */
void reset_nand()
{
	int i=0;
	NFCONF &= ~0x800;
    	for(; i<10; i++);
	NFCMD = 0xff;	//reset command
	wait_idle();
}

/*
 * bit[15]:Enable Nand Flash Controller
 * bit[12]:Initialize ECC
 * bit[11]:Nand Flash nFCE = HIGH(inactive)
 * bit[10:8]:TACLS,Duration = HCLK*(TACLS+1)
 * bit[6:4]:TWRPH0,Duration = HCLK*(TWRPH0+1)
 * bit[2:0]:TWRPH1,Duration = HCLK*(TWRPH1+1) 
 */
//#define	NANDCONFIGVAL	((1<<15)|(1<<12)|(1<<11)|(0x0<<8)|(0x3<<4)|(0x0))
#define	NANDCONFIGVAL	((1<<15)|(1<<12)|(1<<11)|(0x7<<8)|(0x7<<4)|(0x7))
/* 初始化NAND Flash */
void init_nand()
{
	NFCONF = NANDCONFIGVAL;
	reset_nand();
}


/*************************************************************************
*	以下读NAND Flash的代码来自mizi公司的bootloader vivi
*************************************************************************/
#define BUSY 1
inline void wait_idle(void) {
    int i;

    while(!(NFSTAT & BUSY))
      for(i=0; i<10; i++);
}

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

/* low level nand read function */
void nand_read_ll(unsigned char *buf, unsigned long start_addr, int size)
{
    int i, j;

    if ((start_addr & NAND_BLOCK_MASK) || (size & NAND_BLOCK_MASK)) {
        return ;	/* invalid alignment */
    }

    /* chip Enable */
    NFCONF &= ~0x800;
    for(i=0; i<10; i++);

    for(i=start_addr; i < (start_addr + size);) {
      /* READ0 */
      NFCMD = 0;

      /* Write Address */
      NFADDR = i & 0xff;
      NFADDR = (i >> 9) & 0xff;
      NFADDR = (i >> 17) & 0xff;
      NFADDR = (i >> 25) & 0xff;

      wait_idle();

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

    /* chip Disable */
    NFCONF |= 0x800;	/* chip disable */

    return ;
}