[libre-riscv-dev] building a simple barrel processor

[Jacob Lifshay]

I think it's a good idea for me to build a simple prototype RV64IMA barrel
processor using nmigen, since we can evaluate design and performance and I
can gain experience using python and nmigen (haven't actually used it yet).

The design includes the M extension so we can evaluate what might work for
having long instructions (div/rem). The design includes the A extension so
we can evaluate synchronization between harts in a core.

For the memory system, I was thinking we could have a sram for main memory
so we don't need to deal with a ddr3 controller yet.

I think I could get a decently working prototype in a few weeks.

If it has a good enough design and we end up wanting to go with a barrel
processor, we could use it as a base design for our gpu.

Comments?

Jacob Lifshay