分类： 嵌入式
2009-10-30 13:06:10
一 开发板硬件资源:
CPU : s3c2410
SRRAM : 2片 HY57v561620FTP-H
NOR FLASH : 2M AM29LV160DB
NANDFLASH: 64M K9F1208U0B
二 软件准备
所需资源准备
1 uboot官方FTP下载地址
2 下载u-boot-1.1.6源码
u-boot-1.1.6.tar.bz2
三 移植
查看当前目录
[root@localhost u-boot]#pwd
/home/u-boot
1解压u-boot-1.1.6
tar –xjvf u-boot-1.1.6.tar.bz2
cd u-boot-1.1.6
[root@localhost u-boot]#pwd
/home/u-boot/u-boot-1.1.6
2建立自己zq2410开发板的配置
[root@localhost u-boot-1.1.6]cp –r board/smdk2410 board/zq2410
[root@localhost u-boot-1.1.6]cp include/configs/smdk2410.h include/
configs/zq2410.h
zq2410.h是开发板的配置文件，他包括开发板的CPU、系统时钟、RAM、FLASH系 统及其他相关的配置信息，由于u-boot已经支持三星的smdk2410开发板，所以移 植的时候直接拷贝smdk2410的配置文件，做相应的修改即可。
修改顶层Makefile
vi Makefile
找到：
smdk2410_config : unconfig
@$(MKCONFIG) $(@:_config=) arm arm920t smdk2410 NULL s3c24x0 在其后面添加：
zq2410_config : unconfig
@$(MKCONFIG) $(@:_config=) arm arm920t zq2410 NULL s3c24x0 各项的意思如下:
arm: CPU的架构(ARCH)
arm920t: CPU的类型(CPU)，其对应于cpu/arm920t子目录。
zq2410: 开发板的型号(BOARD)，对应于board/zq2410目录。
NULL: 开发者/或经销商(vender)。
s3c24x0: 片上系统(SOC)。
修改include/configs/zq2410.h：
# define CFG_PROMPT “SMDK2410 #”
为：
# define CFG_PROMPT “zq2410 #”
这是u-boot的命令行提示符。
修改board/下相关文件的名字
[root@localhost u-boot-1.1.6]cp –r board/smdk2410/smdk2410.c board/
zq2410/zq2410.c
修改board/zq2410/Makefile
将：
OBJS := smdk2410.o flash.o
改为：
OBJS := zq2410.o flash.o
测试编译能否成功：
make zq2410_config
make
如果没有问题，在u-boot-1.1.6目录下就生成u-boot.bin
在board/zq2410加入NAND Flash读函数，建立nand_read.c，加入如下内容(copy from vivi)：
#include
#include "linux/mtd/mtd.h"
#include "linux/mtd/nand.h"
#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 NFCMD __REGb(NF_BASE + 0x4)
#define NFADDR __REGb(NF_BASE + 0x8)
#define NFDATA __REGb(NF_BASE + 0xc)
#define NFSTAT __REGb(NF_BASE + 0x10)
#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 */
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 */
}
/* 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 0;
}
修改cpu/arm920t/start.S文件
2410的启动代码可以在外部的NAND FLASH上执行，启动时，NAND FLASH的前4KB（地址为0x00000000，OM[1:0]=0）将被装载到SDRAM中被称为Setppingstone的地址中，然后开始执行这段代码。启动以后，这4KB的空间可以做其他用途,在start.S加入搬运代码如下：
...........
...........
copy_loop:
ldmia r0!, {r3-r10} /* copy from source address [r0] */
stmia r1!, {r3-r10} /* copy to target address [r1] */
cmp r0, r2 /* until source end addreee [r2] */
ble copy_loop
#ifdef CONFIG_S3C2410_NAND_BOOT /*这个一定要放在堆栈设置之前*/
bl copy_myself
#endif /*CONFIG_S3C2410_NAND_BOOT*/
#endif /* CONFIG_SKIP_RELOCATE_UBOOT */
/* Set up the stack */
stack_setup:
..................
/********************************************************
* copy u-boot to ram 放在start.S最后的的位置
***************************************************/
#ifdef CONFIG_S3C2410_NAND_BOOT
/*
@ copy_myself: copy u-boot to ram
*/
copy_myself:
mov r10, lr
@ reset NAND
mov r1, #NAND_CTL_BASE
ldr r2, =0xf830 @ initial value
str r2, [r1, #oNFCONF]
ldr r2, [r1, #oNFCONF]
bic r2, r2, #0x800 @ enable chip
str r2, [r1, #oNFCONF]
mov r2, #0xff @ RESET command
strb r2, [r1, #oNFCMD]
mov r3, #0 @ wait
1: add r3, r3, #0x1
cmp r3, #0xa
blt 1b
2: ldr r2, [r1, #oNFSTAT] @ wait ready
tst r2, #0x1
beq 2b
ldr r2, [r1, #oNFCONF]
orr r2, r2, #0x800 @ disable chip
str r2, [r1, #oNFCONF]
@ get read to call C functions
ldr sp, DW_STACK_START @ setup stack pointer
mov fp, #0 @ no previous frame, so fp=0
@ copy UBOOT to RAM
ldr r0, _TEXT_BASE
mov r1, #0x0
mov r2, #0x20000
bl nand_read_ll
teq r0, #0x0
beq ok_nand_read
bad_nand_read:
1: b 1b @ infinite loop
ok_nand_read:
@ verify
mov r0, #0
ldr r1, _TEXT_BASE
mov r2, #0x400 @ 4 bytes * 1024 = 4K-bytes
go_next:
ldr r3, [r0], #4
ldr r4, [r1], #4
teq r3, r4
bne notmatch
subs r2, r2, #4
beq done_nand_read
bne go_next
notmatch:
1: b 1b
done_nand_read:
mov pc, r10
#endif
@ CONFIG_S3C2440_NAND_BOOT
DW_STACK_START:
.word STACK_BASE+STACK_SIZE-4
修改include/configs/zq2410.h文件，添加如下内容：
#define CONFIG_S3C2410_NAND_BOOT 1
#define STACK_BASE 0x33f00000
#define STACK_SIZE 0x8000
#define UBOOT_RAM_BASE 0x30100000
#define NAND_CTL_BASE 0x4e000000
#define bINT_CTL(Nb) _REG(INT_CTL_BASE+(Nb))
#define oNFCONF 0x00
#define oNFCMD 0x04
#define oNFADDR 0x08
#define oNFDATA 0x0c
#define oNFSTAT 0x10
#define oNFECC 0x14
/*--------------------------------------------------------------------*/
#define NAND_MAX_CHIPS 1
修改board/zq2410/Makefile
OBJS := zq2410.o flash.o nand_read.o
在lib_arm/board.c中的start_armboot函数中有这么一句：
#if (CONFIG_COMMANDS & CFG_CMD_NAND)
puts ("NAND:");
nand_init(); /* go init the NAND */
#endif
u-boot 运行至第二阶段进入 start_armboot()函数。其中 nand_init()函数是对 nand flash 的最初初始化函数。其调用与 CFG_NAND_LEGACY 宏有关,如果没定义 CFG_NAND_LEGACY 这个宏,就按照start_armboot()调用 drivers/nand/nand.c 中的 nand_init 函数(该函数在 1.1.6 已经被实现), 但还有个 board_nand_init()函数没实现,需自己添加。如果定义了CFG_NAND_LEGACY,就不使用默认的 nand_init,而调用自己写的 nand_init 函数了,这里我们选择第二种方式。
具体步骤如下：
加入 NAND 闪存芯片型号
在/include/linux/mtd/ nand_ids.h 中对如下结构体赋值进行修改:
static struct nand_flash_dev nand_flash_ids[]= {
......
{"Samsung K9F1208U0M", NAND_MFR_SAMSUNG, 0x76, 26, 0, 3, 0x4000, 0},
......
}
这样对于该款 NAND 闪存芯片的操作才能正确执行。
编写 NAND 闪存初始化函数
在/drivers/nand_legacy/nand_legacy.c 中加入 nand_init()函数。
#if (CONFIG_COMMANDS & CFG_CMD_NAND)
#include
/*----------------------------------------------------------------------*/
typedef enum {
NFCE_LOW,
NFCE_HIGH
} NFCE_STATE;
static inline void NF_Conf(u16 conf)
{
S3C2410_NAND * const nand = S3C2410_GetBase_NAND();
nand->NFCONF = conf;
}
static inline void NF_Cmd(u8 cmd)
{
S3C2410_NAND * const nand = S3C2410_GetBase_NAND();
nand->NFCMD = cmd;
}
static inline void NF_CmdW(u8 cmd)
{
NF_Cmd(cmd);
udelay(1);
}
static inline void NF_Addr(u8 addr)
{
S3C2410_NAND * const nand = S3C2410_GetBase_NAND();
nand->NFADDR = addr;
}
static inline void NF_SetCE(NFCE_STATE s)
{
S3C2410_NAND * const nand = S3C2410_GetBase_NAND();
switch (s) {
case NFCE_LOW:
nand->NFCONF &= ~(1<<11);
break;
case NFCE_HIGH:
nand->NFCONF |= (1<<11);
break;
}
}
static inline void NF_WaitRB(void)
{
S3C2410_NAND * const nand = S3C2410_GetBase_NAND();
while (!(nand->NFSTAT & (1<<0)));
}
static inline void NF_Write(u8 data)
{
S3C2410_NAND * const nand = S3C2410_GetBase_NAND();
nand->NFDATA = data;
}
static inline u8 NF_Read(void)
{
S3C2410_NAND * const nand = S3C2410_GetBase_NAND();
return(nand->NFDATA);
}
static inline void NF_Init_ECC(void)
{
S3C2410_NAND * const nand = S3C2410_GetBase_NAND();
nand->NFCONF |= (1<<12);
}
static inline u32 NF_Read_ECC(void)
{
S3C2410_NAND * const nand = S3C2410_GetBase_NAND();
return(nand->NFECC);
}
extern ulong
nand_probe(ulong physadr);
static inline void NF_Reset(void)
{
int i;
NF_SetCE(NFCE_LOW);
NF_Cmd(0xFF); /* reset command */
for(i = 0; i < 10; i++); /* tWB = 100ns. */
NF_WaitRB(); /* wait 200~500us; */
NF_SetCE(NFCE_HIGH);
}
static inline void NF_Init(void)
{
#if 0 /* a little bit too optimistic */
#define TACLS 0
#define TWRPH0 3
#define TWRPH1 0
#else
#define TACLS 0
#define TWRPH0 4
#define TWRPH1 2
#endif
NF_Conf((1<<15)|(0<<14)|(0<<13)|(1<<12)|(1<<11)|(TACLS<<8)|(TWRPH0<<4)|(TWRPH1<<0));
/*nand->NFCONF = (1<<15)|(1<<14)|(1<<13)|(1<<12)|(1<<11)|(TACLS<<8)|(TWRPH0<<4)|(TWRPH1<<0); */
/* 1 1 1 1, 1 xxx, r xxx, r xxx */
/* En 512B 4step ECCR nFCE=H tACLS tWRPH0 tWRPH1 */
NF_Reset();
}
void
nand_init(void)
{
S3C2410_NAND * const nand = S3C2410_GetBase_NAND();
NF_Init();
#ifdef DEBUG
printf("NAND flash probing at 0x%.8lX\n", (ulong)nand);
#endif
printf ("%4lu MB\n", nand_probe((ulong)nand) >> 20);
}
#endif /* CONFIG_COMMANDS & CFG_CMD_NAND */
/*END*****************************************************/
/*
* Exported variables etc.
*/
可以看到 nand_init()调用 NF_Init()函数,使能 nand flash 控制器和 nand flash;调用 NF_Reset()函数置位,NF_WaitRB()查询 nand flash 的状态,最后在调用 nand_probe((ulong)nand)函数探测 nand flash.
修改include/configs/zq2410.h，在上次修改的基础上加上如下代码，定义 NAND 闪存命令层的底
接口函数等：
#define CFG_NAND_LEGACY 1
//#define NFCE_LOW 0
//#define NFCE_HIGH 1
#define CFG_ENV_IS_IN_NAND 1
#define CFG_NAND_BASE 0x4E000000
#define CMD_SAVEENV
#define CFG_ENV_SIZE 0x10000 /* Total Size of Environment Sector */
#define CFG_ENV_OFFSET 0x20000 /*环境变量在NAND FLASH的0x20000处*/
#define CFG_MONITOR_BASE PHYS_SDRAM_1
/*-----------------------------------------------------------------------
* NAND flash settings
*/
#if (CONFIG_COMMANDS & CFG_CMD_NAND)
#define CFG_NAND_LEGACY
#define CFG_MAX_NAND_DEVICE 1 /* Max number of NAND devices */
#define SECTORSIZE 512
#define ADDR_COLUMN 1
#define ADDR_PAGE 2
#define ADDR_COLUMN_PAGE 3
#define NAND_ChipID_UNKNOWN 0x00
#define NAND_MAX_FLOORS 1
#define NAND_MAX_CHIPS 1
#define NAND_WAIT_READY(nand) NF_WaitRB()
#define NAND_DISABLE_CE(nand) NF_SetCE(NFCE_HIGH)
#define NAND_ENABLE_CE(nand) NF_SetCE(NFCE_LOW)
#define WRITE_NAND_COMMAND(d, adr) NF_Cmd(d)
#define WRITE_NAND_COMMANDW(d, adr) NF_CmdW(d)
#define WRITE_NAND_ADDRESS(d, adr) NF_Addr(d)
#define WRITE_NAND(d, adr) NF_Write(d)
#define READ_NAND(adr) NF_Read()
/* the following functions are NOP's because S3C24X0 handles this in hardware */
#define NAND_CTL_CLRALE(nandptr)
#define NAND_CTL_SETALE(nandptr)
#define NAND_CTL_CLRCLE(nandptr)
#define NAND_CTL_SETCLE(nandptr)
#define CONFIG_MTD_NAND_VERIFY_WRITE 1
#define CONFIG_MTD_NAND_ECC_JFFS2 1
#endif /* CONFIG_COMMANDS & CFG_CMD_NAND */
在zq2410.h中打开命令：
/***********************************************************
* Command definition
***********************************************************/
#define CONFIG_COMMANDS \
(CONFIG_CMD_DFL | \
CFG_CMD_CACHE | \
CFG_CMD_NAND | \ /* 打开 nand flash 命令 */
/*CFG_CMD_EEPROM |*/ \
/*CFG_CMD_I2C |*/ \
/*CFG_CMD_USB |*/ \
CFG_CMD_REGINFO | \
CFG_CMD_DATE | \
CFG_CMD_ELF)
好了，make一下，看看结果，很不幸运，/env_nand.c：206 undefined reference to 'nand_info'等等问题，如图1所示，原来nand flash 真正的擦除和读写函数使用的是 drivers/nand_legacy/ 目录下面的读写、擦除函数
int nand_legacy_erase(struct nand_chip* nand, size_t ofs,size_t len, int clean);
int nand_legacy_rw(struct nand_chip* nand, int cmd,size_t start, size_t len,size_t * retlen, u_char * buf);
修改saveenv中对nand的读写函数为nand_legacy的读写函数，修改common/env_nand.c如下：
#include
#if defined(CFG_ENV_IS_IN_NAND) /* Environment is in Nand Flash */
#include
#include
#include
#include
#include
#if ((CONFIG_COMMANDS&(CFG_CMD_ENV|CFG_CMD_NAND)) == (CFG_CMD_ENV|CFG_CMD_NAND))
#define CMD_SAVEENV
#elif defined(CFG_ENV_OFFSET_REDUND)
#error Cannot use CFG_ENV_OFFSET_REDUND without CFG_CMD_ENV & CFG_CMD_NAND
#endif
#if defined(CFG_ENV_SIZE_REDUND) && (CFG_ENV_SIZE_REDUND != CFG_ENV_SIZE)
#error CFG_ENV_SIZE_REDUND should be the same as CFG_ENV_SIZE
#endif
#ifdef CONFIG_INFERNO
#error CONFIG_INFERNO not supported yet
#endif
/* My Add*/
int nand_legacy_erase(struct nand_chip* nand,
size_t ofs, size_t len, int clean);
int nand_legacy_rw (struct nand_chip* nand, int cmd,
size_t start, size_t len,
size_t * retlen, u_char * buf);
/* My Add*/
extern struct nand_chip nand_dev_desc[CFG_MAX_NAND_DEVICE];
/* info for NAND chips, defined in drivers/nand/nand.c */
//extern nand_info_t nand_info[];
nand_info_t nand_info[CFG_MAX_NAND_DEVICE];
/* references to names in env_common.c */
extern uchar default_environment[];
extern int default_environment_size;
......
......
#else /* ! CFG_ENV_OFFSET_REDUND */
int saveenv(void) /* 2008-6-26 by weij */
{
ulong total;
int ret = 0;
puts ("Erasing Nand...");
//if (nand_erase(&nand_info[0], CFG_ENV_OFFSET, CFG_ENV_SIZE))
if (nand_legacy_erase(nand_dev_desc+0, CFG_ENV_OFFSET, CFG_ENV_SIZE, 0))
return 1;
puts ("Writing to Nand... ");
total = CFG_ENV_SIZE;
//ret = nand_write(&nand_info[0], CFG_ENV_OFFSET, &total, (u_char*)env_ptr);
nand_legacy_rw(nand_dev_desc+0, 0x00 | 0x02, CFG_ENV_OFFSET, CFG_ENV_SIZE, &total, (u_char*)env_ptr);
if (ret || total != CFG_ENV_SIZE)
return 1;
puts ("done\n");
return ret;
}
#endif /* CFG_ENV_OFFSET_REDUND */
......
......
/*
* The legacy NAND code saved the environment in the first NAND device i.e.,
* nand_dev_desc + 0. This is also the behaviour using the new NAND code.
*/
void env_relocate_spec (void)
{
#if !defined(ENV_IS_EMBEDDED)
ulong total;
int ret;
total = CFG_ENV_SIZE;
//ret = nand_read(&nand_info[0], CFG_ENV_OFFSET, &total, (u_char*)env_ptr);
ret=nand_legacy_rw(nand_dev_desc+0, 0x01 | 0x02, CFG_ENV_OFFSET, CFG_ENV_SIZE, &total, (u_char*)env_ptr);
if (ret || total != CFG_ENV_SIZE)
return use_default();
if (crc32(0, env_ptr->data, ENV_SIZE) != env_ptr->crc)
return use_default();
#endif /* ! ENV_IS_EMBEDDED */
}
#endif /* CFG_ENV_OFFSET_REDUND */
......
但我在最后一步：修改common/env_nand.c 之后：
make,出现如下错误：
make[1]: Leaving directory `/home/platform/SMDK2410/u-boot-1.1.6/common'