You should investigate the RISC-V project. It is an open source RISC based ISA along with open source implementations of example processor cores. Then you coul

You should investigate the RISC-V project. It is an open source RISC based ISA along with open source implementations of example processor cores. Then you could have had a processor that was completely open and did not include any proprietary code. https://riscv.org/ https://riscv.org/