uboot代码中的NAND Flash的读写驱动中存在一些错误,需要进行修改后才能完成,主要修改drivers/mtd/nand/s3c2410_nand.c文件,首先修改27行如下:
#define NF_BASE 0x4e000000 #if defined(CONFIG_S3C2410) #define S3C2410_NFCONF_EN (1<<15) #define S3C2410_NFCONF_512BYTE (1<<14) #define S3C2410_NFCONF_4STEP (1<<13) #define S3C2410_NFCONF_INITECC (1<<12) #define S3C2410_NFCONF_nFCE (1<<11) #define S3C2410_NFCONF_TACLS(x) ((x)<<8) #define S3C2410_NFCONF_TWRPH0(x) ((x)<<4) #define S3C2410_NFCONF_TWRPH1(x) ((x)<<0) #define S3C2410_ADDR_NALE 4 #define S3C2410_ADDR_NCLE 8 #endif #if defined(CONFIG_S3C2440) #define S3C2410_NFCONT_EN (1<<0) #define S3C2410_NFCONT_INITECC (1<<4) #define S3C2410_NFCONT_nFCE (1<<1) #define S3C2410_NFCONT_MAINECCLOCK (1<<5) #define S3C2410_NFCONF_TACLS(x) ((x)<<12) #define S3C2410_NFCONF_TWRPH0(x) ((x)<<8) #define S3C2410_NFCONF_TWRPH1(x) ((x)<<4) #define S3C2410_ADDR_NALE 0x08 #define S3C2410_ADDR_NCLE 0x0c #endif
u-boot.2010.09自带的S3C2410_nand.c的s3c2410_hwcontrol函数有错。在此函数中,把chip->IO_ADDR_W值改写了,导致在写数据时出现错误。解决方法是使用一全局变量代替 chip->IO_ADDR_W。在 s3c2410_hwcontrol 函数上一行定义这个全局变量,然后修改 s3c2410_hwcontrol 函数(修改71行),让它支持 S3C2440,如下:
ulong IO_ADDR_W = NF_BASE; static void s3c2410_hwcontrol(struct mtd_info *mtd, int cmd, unsigned int ctrl) { //struct nand_chip *chip = mtd->priv; struct s3c2410_nand *nand = s3c2410_get_base_nand(); debugX(1, "hwcontrol(): 0x%02x 0x%02x\n", cmd, ctrl); if (ctrl & NAND_CTRL_CHANGE) { //ulong IO_ADDR_W = (ulong)nand; IO_ADDR_W = (ulong)nand; if (!(ctrl & NAND_CLE)) IO_ADDR_W |= S3C2410_ADDR_NCLE; if (!(ctrl & NAND_ALE)) IO_ADDR_W |= S3C2410_ADDR_NALE; //chip->IO_ADDR_W = (void *)IO_ADDR_W; #if defined(CONFIG_S3C2410) if (ctrl & NAND_NCE) writel(readl(&nand->NFCONF) & ~S3C2410_NFCONF_nFCE, &nand->NFCONF); else writel(readl(&nand->NFCONF) | S3C2410_NFCONF_nFCE, &nand->NFCONF); #endif #if defined(CONFIG_S3C2440) if (ctrl & NAND_NCE) writel(readl(&nand->NFCONT) & ~S3C2410_NFCONT_nFCE, &nand->NFCONT); else writel(readl(&nand->NFCONT) | S3C2410_NFCONT_nFCE, &nand->NFCONT); #endif } if (cmd != NAND_CMD_NONE) //writeb(cmd, chip->IO_ADDR_W); writeb(cmd, (void *)IO_ADDR_W); }
然后修改函数s3c2410_nand_enable_hwecc如下:
void s3c2410_nand_enable_hwecc(struct mtd_info *mtd, int mode) { struct s3c2410_nand *nand = s3c2410_get_base_nand(); debugX(1, "s3c2410_nand_enable_hwecc(%p, %d)\n", mtd, mode); #if defined(CONFIG_S3C2410) writel(readl(&nand->NFCONF) | S3C2410_NFCONF_INITECC, &nand->NFCONF); #endif #if defined(CONFIG_S3C2440) writel(readl(&nand->NFCONT) | S3C2410_NFCONT_INITECC, &nand->NFCONT); #endif }
最后修改board_nand_init 函数如下:
int board_nand_init(struct nand_chip *nand) { u_int32_t cfg; u_int8_t tacls, twrph0, twrph1; struct s3c24x0_clock_power *clk_power = s3c24x0_get_base_clock_power(); struct s3c2410_nand *nand_reg = s3c2410_get_base_nand(); debugX(1, "board_nand_init()\n"); writel(readl(&clk_power->CLKCON) | (1 << 4), &clk_power->CLKCON); #if defined(CONFIG_S3C2410) /* initialize hardware */ twrph0 = 3; twrph1 = 0; tacls = 0; cfg = S3C2410_NFCONF_EN; cfg |= S3C2410_NFCONF_TACLS(tacls - 1); cfg |= S3C2410_NFCONF_TWRPH0(twrph0 - 1); cfg |= S3C2410_NFCONF_TWRPH1(twrph1 - 1); writel(cfg, &nand_reg->NFCONF); /* initialize nand_chip data structure */ nand->IO_ADDR_R = nand->IO_ADDR_W = (void *)&nand_reg->NFDATA; #endif #if defined(CONFIG_S3C2440) /* initialize hardware */ tacls = 0; twrph0 = 4; twrph1 = 2; cfg = 0; cfg |= S3C2410_NFCONF_TACLS(tacls - 1); cfg |= S3C2410_NFCONF_TWRPH0(twrph0 - 1); cfg |= S3C2410_NFCONF_TWRPH1(twrph1 - 1); writel(cfg, &nand_reg->NFCONF); cfg = (0<<13)|(0<<12)|(0<<10)|(0<<9)|(0<<8)|(0<<6)|(0<<5)|(1<<4)|(0<<1)|(1<<0); writel(cfg, &nand_reg->NFCONT); /* initialize nand_chip data structure */ nand->IO_ADDR_R = nand->IO_ADDR_W = (void *)&nand_reg->NFDATA; #endif nand->select_chip = NULL; ……