So, just to double-check. When you flash u-boot, you use the file "u-boot-sunxi-with-spl.bin" and flash it as follows?:
Note that the procedure differs between the Rockchip and Allwinner boards with regard to u-boot.
Code:
dd if=u-boot-sunxi-with-spl.bin of=/dev/sdX bs=1024 seek=8 conv=notrunc
Note that the procedure differs between the Rockchip and Allwinner boards with regard to u-boot.