bsc VS myhdl

Many companies do just write entire modern SoCs in straight Verilog (maybe with some autogenerated Verilog hacked in there) with no other major organization tools aside from the typical project management stuff. The load-store unit of a modern CPU alone easily exceeds 10k lines of Verilog. It's a similar thing as people who work with kernels—after all, the page table management code in a modern operating system like Linux is absolutely monstrous but still people are able to understand it well enough to be able to make the changes they need and get out.

If you are interested in other languages which hope to make this sort of stuff easier, I'd recommend taking a look at design productivity languages like Chisel and it's associated Chipyard [1], SpinalHDL [2], and Bluespec [3]. Each of these are meant to make defining extremely complex hardware more manageable for humans and there's a lot of interesting work going on right now with each of them.

[1] https://github.com/ucb-bar/chipyard

[2] https://github.com/SpinalHDL/SpinalHDL

[3] https://github.com/B-Lang-org/bsc

What are your thoughts on other HDLs like Chisel or BlueSpec when it comes to better type checking?

In a previous project we used Haskell that compiled down to Verilog to design hardware. Think along the lines of BlueSpec or Clash. Haskell would force you to spell out the new state as a function of the old state of the system. This would let us do gate-level simulations of the hardware we designed. Coupled with Haskell's penchant for using primes to mean "the new value of", stuff like x' = f x was very common.

You should look at Bluespec, they are doing some interesting stuff.

And I've been involved in a project that's making heavy use of Bluespec: https://github.com/B-Lang-org/bsc/

Same problem though - you have to transpile it down to Verilog to use it in anything beyond a simulation.

FPGA Thread: Bluespec SystemVerilog is now completely open source, very nice HDL although quite opinionated.

https://github.com/B-Lang-org/bsc

it's Haskell underneath (https://xkcd.com/356/)

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