Microwatt is a small and easy-to-understand open-source softcore written in VHDL 2008. It can be simulated using the ghdl simulator or built directly for a hardware target board. To build Micropython, a cross compiler may be needed if not building on a ppc64le box. The Microwatt project uses ghdl for simulation, and it recommends building ghdl with the LLVM or gcc backend. Users can also use Docker or Podman to build Microwatt. Additionally, instructions are provided for synthesis on Xilinx FPGAs using Vivado, running Linux on Microwatt, creating a userspace with buildroot, and testing the functionality of Microwatt.
https://github.com/antonblanchard/microwatt