修改UBOOT支持NAND FLASH 1、把drivers\mtd\nand\s3c2410_nand.c复制为s3c2440_nand.c
在之前移植uboot时去掉了#define CONFIG_CMD_NAND，现在需要打开。
修改：include/configs/smdk2440.h: #define CONFIG_CMD_NAND
编译查看是否编译通过。
根据打印信息分析，问题出现在s3c2410_nand.c文件。
s3c2410_hwcontrol->struct s3c2410_nand没有定义， 把drivers\mtd\nand\s3c2410_nand.c复制为s3c2440_nand.c
修改makefile：
COBJS-$(CONFIG_NAND_S3C2410) += s3c2410_nand.o COBJS-$(CONFIG_NAND_S3C2440) += s3c2440_nand.o
修改include/configs/smdk2440.h:
#define CONFIG_NAND_S3C2440(makefile根据这个宏编译s3c2440_nand.c)
2、根据数据手册更改s3c2440_nand内容
分析过程： nand_init nand_init_chip board_nand_init 设置nand_chip结构体, 提供底层的操作函数 nand_scan nand_scan_ident nand_set_defaults chip->select_chip = nand_select_chip; chip->cmdfunc = nand_command; chip->read_byte = busw ? nand_read_byte16 : nand_read_byte; nand_get_flash_type chip->select_chip chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1); nand_command() // 即可以用来发命令，也可以用来发列地址(页内地址)、行地址(哪一页) chip->cmd_ctrl s3c2440_hwcontrol chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1); *maf_id = chip->read_byte(mtd); *dev_id = chip->read_byte(mtd);
代码修改如下：drivers\mtd\nand\s3c2440_nand.c
/* * (C) Copyright 2006 OpenMoko, Inc. * Author: Harald Welte <laforge@openmoko.org> * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation; either version 2 of * the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, * MA 02111-1307 USA */ #include <common.h> #include <nand.h> #include <asm/arch/s3c24x0_cpu.h> #include <asm/io.h> #define S3C2440_NFCONF_EN (1<<15) #define S3C2440_NFCONF_512BYTE (1<<14) #define S3C2440_NFCONF_4STEP (1<<13) #define S3C2440_NFCONF_INITECC (1<<12) #define S3C2440_NFCONF_nFCE (1<<11) #define S3C2440_NFCONF_TACLS(x) ((x)<<12) #define S3C2440_NFCONF_TWRPH0(x) ((x)<<8) #define S3C2440_NFCONF_TWRPH1(x) ((x)<<4) #define S3C2440_ADDR_NALE 4 #define S3C2440_ADDR_NCLE 8 #ifdef CONFIG_NAND_SPL /* in the early stage of NAND flash booting, printf() is not available */ #define printf(fmt, args...) static void nand_read_buf(struct mtd_info *mtd, u_char *buf, int len) { int i; struct nand_chip *this = mtd->priv; for (i = 0; i < len; i++) buf[i] = readb(this->IO_ADDR_R); } #endif /* ctrl : 表示做什么, 选中芯片/取消选中, 发命令还是发地址 * * dat : 命令值或地址值 */ static void s3c2440_hwcontrol(struct mtd_info *mtd, int dat, unsigned int ctrl) { struct s3c2440_nand *nand = s3c2440_get_base_nand(); if (ctrl & NAND_CLE) { /* 发命令 */ writeb(dat, &nand->nfcmd); } else if(ctrl & NAND_ALE) { /* 发地址 */ writeb(dat, &nand->nfaddr); } } static void s3c2440_nand_select(struct mtd_info *mtd, int chipnr) { struct s3c2440_nand *nand = s3c2440_get_base_nand(); switch (chipnr) { case -1: /* 取消选中 */ nand->nfcont |= (1<<1); break; case 0: /* 选中 */ nand->nfcont &= ~(1<<1); break; default: BUG(); } } static int s3c2440_dev_ready(struct mtd_info *mtd) { struct s3c2440_nand *nand = s3c2440_get_base_nand(); debug("dev_ready\n"); return readl(&nand->nfstat) & 0x01; } #ifdef CONFIG_S3C2440_NAND_HWECC void s3c2440_nand_enable_hwecc(struct mtd_info *mtd, int mode) { struct s3c2440_nand *nand = s3c2440_get_base_nand(); debug("s3c2440_nand_enable_hwecc(%p, %d)\n", mtd, mode); writel(readl(&nand->nfconf) | S3C2440_NFCONF_INITECC, &nand->nfconf); } static int s3c2440_nand_calculate_ecc(struct mtd_info *mtd, const u_char *dat, u_char *ecc_code) { struct s3c2440_nand *nand = s3c2440_get_base_nand(); ecc_code[0] = readb(&nand->nfecc); ecc_code[1] = readb(&nand->nfecc + 1); ecc_code[2] = readb(&nand->nfecc + 2); debug("s3c2410_nand_calculate_hwecc(%p,): 0xx 0xx 0xx\n", mtd , ecc_code[0], ecc_code[1], ecc_code[2]); return 0; } static int s3c2410_nand_correct_data(struct mtd_info *mtd, u_char *dat, u_char *read_ecc, u_char *calc_ecc) { if (read_ecc[0] == calc_ecc[0] && read_ecc[1] == calc_ecc[1] && read_ecc[2] == calc_ecc[2]) return 0; printf("s3c2410_nand_correct_data: not implemented\n"); return -1; } #endif 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 s3c2440_nand *nand_reg = s3c2440_get_base_nand(); debug("board_nand_init()\n"); writel(readl(&clk_power->clkcon) | (1 << 4), &clk_power->clkcon); /* initialize hardware */ #if defined(CONFIG_S3C24XX_CUSTOM_NAND_TIMING) tacls = CONFIG_S3C24XX_TACLS; twrph0 = CONFIG_S3C24XX_TWRPH0; twrph1 = CONFIG_S3C24XX_TWRPH1; #else tacls = 4; twrph0 = 8; twrph1 = 8; #endif cfg = S3C2440_NFCONF_EN; cfg |= S3C2440_NFCONF_TACLS(tacls - 1); cfg |= S3C2440_NFCONF_TWRPH0(twrph0 - 1); cfg |= S3C2440_NFCONF_TWRPH1(twrph1 - 1); writel(cfg, &nand_reg->nfconf); /* 使能NAND Flash控制器, 初始化ECC, 禁止片选 */ writel((1<<4)|(1<<1)|(1<<0), &nand_reg->nfcont); /* initialize nand_chip data structure */ nand->IO_ADDR_R = (void *)&nand_reg->nfdata; nand->IO_ADDR_W = (void *)&nand_reg->nfdata; nand->select_chip = s3c2440_nand_select; /* read_buf and write_buf are default */ /* read_byte and write_byte are default */ #ifdef CONFIG_NAND_SPL nand->read_buf = nand_read_buf; #endif /* hwcontrol always must be implemented */ nand->cmd_ctrl = s3c2440_hwcontrol; nand->dev_ready = s3c2440_dev_ready; #ifdef CONFIG_S3C2410_NAND_HWECC nand->ecc.hwctl = s3c2440_nand_enable_hwecc; nand->ecc.calculate = s3c2440_nand_calculate_ecc; nand->ecc.correct = s3c2410_nand_correct_data; nand->ecc.mode = NAND_ECC_HW; nand->ecc.size = CONFIG_SYS_NAND_ECCSIZE; nand->ecc.bytes = CONFIG_SYS_NAND_ECCBYTES; #else nand->ecc.mode = NAND_ECC_SOFT; #endif #ifdef CONFIG_S3C2410_NAND_BBT nand->options = NAND_USE_FLASH_BBT; #else nand->options = 0; #endif debug("end of nand_init\n"); return 0; }重新编译烧写。
到此，uboot成功识别nandflash。
