三星 vivi 源码 有兴趣的就看看吧

				/* 				 * vivi/s3c2410/nand_read.c: Simple NAND read functions for booting from NAND				 *				 * Copyright (C) 2002 MIZI Research, Inc.				 *				 * Author: Hwang, Chideok 				 * Date  : $Date: 2004/02/04 06:22:24 $				 *				 * $Revision: 1.1.1.1 $				 * $Id: param.c,v 1.9 2002/07/11 06:17:20 nandy Exp 				 *				 * History				 *				 * 2002-05-xx: Hwang, Chideok 				 *				 * 2002-05-xx: Chan Gyun Jeong 				 *				 * 2002-08-10: Yong-iL Joh 				 *				 */								#include 								#define __REGb(x)	(*(volatile unsigned char *)(x))				#define __REGi(x)	(*(volatile unsigned int *)(x))				#define NF_BASE		0x4e000000								#define NFCONF		__REGi(NF_BASE + 0x0)				#define NFCONT		__REGi(NF_BASE + 0x4)				#define NFCMD		__REGb(NF_BASE + 0x8)				#define NFADDR		__REGb(NF_BASE + 0xC)				#define NFDATA		__REGb(NF_BASE + 0x10)				#define NFSTAT		__REGb(NF_BASE + 0x20)								//#define GPDAT		__REGi(GPIO_CTL_BASE+oGPIO_F+oGPIO_DAT)								#define NAND_CHIP_ENABLE  (NFCONT &= ~(1				#define NAND_CHIP_DISABLE (NFCONT |=  (1				#define NAND_CLEAR_RB	  (NFSTAT |=  (1				#define NAND_DETECT_RB	  { while(! (NFSTAT&(1								#define BUSY 4				inline void wait_idle(void) {					while(!(NFSTAT & BUSY));					NFSTAT |= BUSY;				}								#define NAND_SECTOR_SIZE	512				#define NAND_BLOCK_MASK		(NAND_SECTOR_SIZE - 1)								/* low level nand read function */				int				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 -1;	/* invalid alignment */					}									NAND_CHIP_ENABLE;									for(i=start_addr; i < (start_addr + size);) {						/* READ0 */						NAND_CLEAR_RB;	    						NFCMD = 0;										/* Write Address */						NFADDR = i & 0xff;						NFADDR = (i >> 9) & 0xff;						NFADDR = (i >> 17) & 0xff;						NFADDR = (i >> 25) & 0xff;										NAND_DETECT_RB;										for(j=0; j < NAND_SECTOR_SIZE; j++, i++) {							*buf = (NFDATA & 0xff);							buf++;						}					}					NAND_CHIP_DISABLE;					return 0;				}