Hi, friend!
According to the symptom provided by you, your error is caused by a DDR error. You are advised to contact the TAC center to check whether the hardware is damaged.
@@@[ 3.305309] kbox: ddrram: verify fs magic fail. It's ok if first time using this device
[ 3.404626] **** Total Boot time: 3404 ms, uncompress initrd cost 2642 ms ****
............entering rc.local..............
UBI device number 3, total 3336 LEBs (847183872 bytes, 807.9 MiB), available 0 LEBs (0 bytes), LEB size 253952 bytes (248.0 KiB)
Bootloader CMS check result is true
Boot from main bootloader