Microwatt and GHDL - An Open Hardware CPU written in VHDL, Synthesized with Open Source Tools

Speakers: Anton Blanchard, IBM & Tristan Gingold, CERN

Microwatt is a 64 bit POWER OpenISA soft processor, written in VHDL. Over time it has grown from supporting Micropython, to Zephyr and most recently Linux.

From its original inception, Microwatt has relied heavily on GHDL, the Open Source VHDL simulator. GHDL has very recently added synthesis support and together with Yosys and Nextpnr allows for a completely open source toolchain for FPGAs.

This presentation will give an overview of the Microwatt core. It will also include an overview of GHDL and how it can be used for both simulation and synthesis of a medium complexity VHDL project.