This is a RV32IMZcsr ISA CPU implementation, based off of a TPU CPU design. It is very simple, but has run rv32i-compiled GCC toolchain binaries at over 200MHz on a Digilent Arty S7-50 board, built with Xilinx Spartan 7 tools.

When used in the ArtyS7-RPU-SoC @ 100MHZ it can run DooM timedemo3 at ~8fps, and boot operating systems such as Zephyr RTOS.

RPU Core overview

You can download the RPU CPU here