Enable GCC
export PATH="/usr/local/gcc-linaro-7.3.1-2018.05-x86_64_aarch64-linux-gnu/bin:$PATH"


Configure kernel files
cd /home/marsboard/rockchip-5.0/rockchip-bsp-5.0/kernel
export ARCH=arm64
export CROSS_COMPILE=aarch64-linux-gnu-
make rockchip_cm4_linux_defconfig

Start compiling
cd /home/marsboard/rockchip-5.0/rockchip-bsp-5.0/
./build/mk-kernel.sh rk3566-marsboard-cm4


clean compiling
cd /home/marsboard/rockchip-5.0/rockchip-bsp-5.0/kernel
make clean

Compiled kernel and DTB
/home/marsboard/rockchip-5.0/rockchip-bsp-5.0/kernel/arch/arm64/boot/Image

/home/marsboard/rockchip-5.0/rockchip-bsp-5.0/kernel/arch/arm64/boot/dts/rockchip/rk3566-marsboard-cm4.dtb