2.6.36 mostly works, except for framebuffer console.

3.0 has most drivers forward-ported and should work pretty well.

3.3 only have core CPU support, basically no drivers at all yet.

Source is available from the git repository at https://github.com/amery/linux-allwinner. Branches are also described there.

4.0 apparently has a kernel bug. From the September 2016 mailing list archive: "the problem is somewhere around 4.0rc5 and 4.0rc6. i.e. 4.0rc5 works, 4.0rc6 doesn't."

(That and/or 4.7 has a kernel bug. From the February 2017 mailing list archive: "4.7rc0-4.7rc5 bug has to be found. it's still present in all mainline kernels since (appx) 4.7rc4")