uboot常用命令

uboot常用命令：

一、help

1、help

列出当前uboot所有支持的命令

2、help 命令

查看指定命令的帮助

示例：

hisilicon # help setenv  
setenv - set environment variables

Usage:
setenv [-f] name value ...
    - [forcibly] set environment variable 'name' to 'value ...'
setenv [-f] name
    - [forcibly] delete environment variable 'name'

二、reset

重启uboot

三、boot/bootm

1、boot

默认从bootcmd中启动内核

2、bootm

从内存中启动内核

示例：

sf probe 0
sf read 0x42000000 0x100000 0x500000
bootm 0x42000000

四、printenv/setenv/saveenv

1、printenv

打印所有环境变量的值

2、setenv

设置/修改/删除环境变量的值

3、saveenv

保存环境变量，环境变量修改过后必须执行此命令才可以保存起来，否则重启后环境变量就恢复了

示例：

setenv bootargs 'mem=256M console=ttyAMA0,115200 root=/dev/mtdblock2 rw rootfstype=jffs2 mtdparts=hi_sfc:1M(boot),5M(kernel),26M(rootfs)'
setenv bootcmd 'sf probe 0;sf read 0x42000000 0x100000 0x500000;bootm 0x42000000'

五、loadb/loadx/loady

1、loadb

从串口下载二进制文件（kermit mode）

2、loadx

从串口下载二进制文件（xmodem mode）

3、loady

从串口下载二进制文件（ymodem mode）

示例：

嵌入式设备端

hisilicon # loady 42000000
## Ready for binary (ymodem) download to 0x42000000 at 115200 bps...
Starting ymodem transfer.  Press Ctrl+C to cancel.
Transferring u-boot-hi3521dv200.bin...
  100%     202 KB       3 KB/sec    00:00:56       1 Errors  

## Total Size      = 0x00032962 = 207202 Bytes

win10端

SecureCRT -> Transfer -> Send Ymodem -> 下载文件 -> 确定

六、mw/md

1、mw（mw.b、mw.w、mw.l）

用于修改内存地址上的值

2、md（md.b、md.w、md.l）

用于查看内存地址上的值

示例：

hisilicon # mw.b 42000000 55 100000
hisilicon # md.b 42000000 100      
42000000: 55 55 55 55 55 55 55 55 55 55 55 55 55 55 55 55    UUUUUUUUUUUUUUUU
42000010: 55 55 55 55 55 55 55 55 55 55 55 55 55 55 55 55    UUUUUUUUUUUUUUUU
42000020: 55 55 55 55 55 55 55 55 55 55 55 55 55 55 55 55    UUUUUUUUUUUUUUUU
42000030: 55 55 55 55 55 55 55 55 55 55 55 55 55 55 55 55    UUUUUUUUUUUUUUUU
42000040: 55 55 55 55 55 55 55 55 55 55 55 55 55 55 55 55    UUUUUUUUUUUUUUUU
42000050: 55 55 55 55 55 55 55 55 55 55 55 55 55 55 55 55    UUUUUUUUUUUUUUUU
42000060: 55 55 55 55 55 55 55 55 55 55 55 55 55 55 55 55    UUUUUUUUUUUUUUUU
42000070: 55 55 55 55 55 55 55 55 55 55 55 55 55 55 55 55    UUUUUUUUUUUUUUUU
42000080: 55 55 55 55 55 55 55 55 55 55 55 55 55 55 55 55    UUUUUUUUUUUUUUUU
42000090: 55 55 55 55 55 55 55 55 55 55 55 55 55 55 55 55    UUUUUUUUUUUUUUUU
420000a0: 55 55 55 55 55 55 55 55 55 55 55 55 55 55 55 55    UUUUUUUUUUUUUUUU
420000b0: 55 55 55 55 55 55 55 55 55 55 55 55 55 55 55 55    UUUUUUUUUUUUUUUU
420000c0: 55 55 55 55 55 55 55 55 55 55 55 55 55 55 55 55    UUUUUUUUUUUUUUUU
420000d0: 55 55 55 55 55 55 55 55 55 55 55 55 55 55 55 55    UUUUUUUUUUUUUUUU
420000e0: 55 55 55 55 55 55 55 55 55 55 55 55 55 55 55 55    UUUUUUUUUUUUUUUU
420000f0: 55 55 55 55 55 55 55 55 55 55 55 55 55 55 55 55    UUUUUUUUUUUUUUUU

七、tftp

通过网口下载文件到设备

示例：

hisilicon # mw.b 42000000 ff 100000
hisilicon # tftp 42000000 u-boot-hi3521dv200.bin
Hisilicon ETH net controler
eth0 : phy status change : LINK=UP : DUPLEX=FULL : SPEED=100M
Using eth0 device
TFTP from server 172.16.80.91; our IP address is 172.16.80.99
Filename 'u-boot-hi3521dv200.bin'.
Load address: 0x42000000
Loading: ###############
         1.8 MiB/s
done
Bytes transferred = 207166 (3293e hex)

八、ping

测试网络是否正常通信

示例：

hisilicon # ping 172.16.80.91
Hisilicon ETH net controler
eth0 : phy status change : LINK=UP : DUPLEX=FULL : SPEED=100M
Using eth0 device
host 172.16.80.91 is alive

九、nand

1、nand info

2、nand erase

3、nand read

4、nand write

示例：

mw.b 42000000 ff 100000
tftp 42000000 u-boot-hi3521dv200.bin
nand erase 0 100000
nand write 42000000 0 100000