记录uboot转到内核时相关的指令：
setenv set_ubi 'set mtdids nand0=nand0; set mtdparts mtdparts=nand0:0x7680000@0x900000(fs); ubi part fs' setenv bootkernel 'ubi read 0x84000000 kernel && bootm' setenv bootargs 'ubi.mtd=ubi root=/dev/ubiblock0_1 rootfstype=squashfs,ubi' setenv my_boot 'run set_ubi; run bootkernel' setenv bootcmd 'run my_boot' saveenv