The difference between flashing:
Interrupt U-Boot and run these commands:
setenv bootcmd "setenv mtdids nand0=nand0 && set mtdparts
mtdparts=nand0:0xDC00000@0x2400000(firmware) && ubi part firmware &&
ubi read 0x44000000 kernel 0x6e0000 && bootm"
saveenv