Cubietruck definitely works! There is no pre-configured image, so you need to build your own. Easiest is to start with another Allwinner image (say the Cubieboard2 one), replace U-Boot with the one for your board, and add your dtb.

Look at ports/sysutils/u-boot-cubieboard2 for a template on how to build a suitable U-Boot, and sys/boot/fdt/dts/arm/cubieboard2.dts for a template for your dtb.

For a detailed list of supported hardware, have a look at the wiki: https://wiki.freebsd.org/FreeBSD/arm/Allwinner