freepdk-45nm VS myhdl

Pretty neat, a python tool that converts Verilog to an IC layout so that you can make your own custom SOC (assuming you have a substantial budget to pay for fab).

Since it's not clearly stated on the front page, I had to go digging to figure out what processes it supports. Looks like FreePDK45, which is "an open-source generic process design kit (PDK) (i.e., does not correspond to any real process and cannot be fabricated)" [0], ASAP7 "Warning Work in progress (not ready for use)" [1] and Skywater130 which "As of May 2020, this repository is targeting the SKY130 process node. If the SKY130 process node release is successful then in the future more advanced technology nodes may become available." [2] The floorplanner supports their ZeroSOC [3] which I guess is based on TitanSOC [4]

If this sounds negative, it's not, I just couldn't figure out what processes this was intended for without digging. ASAP7 is Arm and NCSU, and Skywater130 is Skywater and Google.

[0] https://github.com/mflowgen/freepdk-45nm

Thank you for tackling this critical problem for logic designiners. I think the tools available are much too old for fast paced workflows.

From my experience attempting to get a similar workflow down for my company:

I tried to use verilator a while back but ultimately I couldn't because it didn't have same constraints in the verilog language features that I was going to use in production. It doesn't even matter who was missing a feature, verilator or the proprietary tool, it was just about getting them to be same that caused the cognitive dissonance that I didn't want to deal with.

I ultimately decided to move away from verilator and use the clunky proprietary tools since it was what would be used in production. Getting "verilator compatibility" seemed like a "nice to have".

Second, the a winning local-first framework of verilator wasn't really established. You show in your example running a test from the yaml file using what looks like a bash script. Even as an experienced programmer who knows bash and sh well, I still find it very hard to write complex thoughts in it. The last high level attempt I found to bridge this gap is likely https://www.myhdl.org/ I don't know them personally, but it seemed like they had some very good thoughts on what makes writing good hardware level tests good. I think it would be worth reaching out to them if you haven't already.

The one thing that even more critical was a way to run our tests locally. The 10-20 seconds it takes to start a docker image (best case) in the cloud is really frustrating when you are "so close to finding a bug" and you "just want to see if this one line change is going to fix it". Once we got our whole pipeline going, it would take 1-6 minutes to "start a run" since it often had to rebuild previous steps that cache large parts of the design.

So I think you will want to see how you can help bring people's "local's first" workflows slowly into the cloud. Some tools (or just tutorials) that help you take a failing test, and run it locally and on the cloud will be really good especially as you get people to transition!

Also PyMTL, PyRTL, and MyHDL.

MyHDL

Any hardware designers here who use Python for designing hardware? There are a bunch of libraries that all seem promising MyHDL, PyRTL, PyVerilog, PyLog, PyMTL3, ... All seem to work roughly the same. Write code in Python and transpile it to VHDL/Verilog. Which of these are popular and well-maintained? MyHDL looks good but it's last release was 0.10 in 2018 and for hardware design you don't want to rely on 0.x software. Anything like Chisel for Python.

It is : https://www.myhdl.org/

Personally I have fond memories of MyHDL [0], which may be seen as another "code-to-silicon" converter (or at least as the first step of a code-to-silicon workflow). I used it only briefly, and on a school project that had surprisingly little to do with actual hardware design [1], but it really felt "Pythonic" in the best possible way.

[0]: https://www.myhdl.org/

[1]: https://github.com/lou1306/gssi/tree/master/2pc