Free drivers for ARM graphics

opengl is too high level, especially when you take glsl into account.

The closest equivalent in a more traditional gpu architecture to what is open in rp-i would be an open EGL layer (which would let you implement support for wayland or some new window system). The r-pi does have some advantage that libc version isn't a problem, but even that isn't too big of an issue w/ something like libhybris (which would be a considerably more simple thing if it didn't have to emulate one EGL on top of another).