Martin Lucina: > (arm-trusted-firmware) $ make PLAT=sun50iw1p1 DEBUG=1 bl31 CROSS_COMPILE=aarch64- linux-gnu- > (u-boot) $ make ARCH=arm CROSS_COMPILE=aarch64-linux-gnu- a64-olinuxino_defconfig > (u-boot) $ make ARCH=arm CROSS_COMPILE=aarch64-linux-gnu- BL31=$(pwd)/../arm-trusted-firmware/build/sun50iw1p1/debug/bl31.bin Try ARCH=arm64. No idea if it helps. Joonas