uBoot中环境变量无saveenv命令

最近烧写mmc，发现uboot内saveenv命令丢失，导致环境变量无法设置，请教了
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md      - memory display
mii     - MII utility commands
mm      - memory modify (auto-incrementing address)
mmc     - MMC sub system
mmcinfo - display MMC info
mtest   - ** RAM read/write test
mw      - memory write (fill)
nfs     - boot image via network using NFS protocol
nm      - memory modify (constant address)
ping    - send ICMP ECHO_REQUEST to network host
printenv- print environment variables
protect - enable or disable FLASH write protection
rarpboot- boot image via network using RARP/TFTP protocol
reset   - Perform RESET of the CPU
run     - run commands in an environment variable
setenv  - set environment variables
sf      - SPI flash sub-system
sleep   - delay execution for some time
source  - run script from memory
sspi    - SPI utility commands
tftpboot- boot image via network using TFTP protocol
version - print monitor version
......

我们的uboot?您怎么弄的会缺失这个，重新烧写吧

重新烧写结果一样，见了鬼了。