long story, there's a new project underway which is to create a 3D GPU (and associated complete processor) entirely as a libre project, using RISC-V as the basis. there's a lot to get done: the roadmap is quite straightforward: http://libre-riscv.org/3d_gpu/roadmap/
it'll be a vulkan3d *software* driver written in rust and using llvm. where and if absolutely strictly necessary intrinsic inline assembler will be placed into the rust code: for the rest it will be straight to llvm, and from there using a hardware-level parallelism API called "SimpleV" which will take care of, at the hardware level, a variable-length "vectorisation" aka variable-size SIMD (which is a really *really* misleading way to describe it but SIMD and vectorisation is what most people know).
for the most part this is a *software* project not a hardware one so if anyone has software engineering skills, documentation skills or anything else, do get in touch.
mailing lists: http://lists.libre-riscv.org
l.