Hi, I folow the step by step: http://wiki.friendlyarm.com/wiki/index.php/NanoPC-T3#Compile_U-Boot_2 git clone https://github.com/friendlyarm/u-boot.git cd u-boot git checkout nanopi2-v2016.01 make make s5p6818_nanopi3_defconfig make CROSS_COMPILE=aarch64-linux- Using fastboot tool to flash u-boot.bi...