I've been delving into VLSI but realize it is quite a complex topic. Can anyone familiar with this provide a TLDR? Is the idea here that instead of verilog, etc. one can use python to code a PLD/FPGA?
Programmable logic circuits are presented as hardware libraries called overlays. These overlays are analogous to software libraries. A software engineer can select the overlay that best matches their application. The overlay can be accessed through an application programming interface (API). Creating a new overlay still requires engineers with expertise in designing programmable logic circuits.
You might say "why doesn't this exist already", but the whole ecosystem is currently quite hard to use (think GPU programming but from 5 or 10 years ago) so putting some nice interfaces on it could be a big step. Will be interesting to watch.
I like the overlay idea as a stepping stone to something more flexible. I personally think in the near future there'll be increased demand for languages like Bluespec, which IIRC allow you to specify hardware and code that runs on that hardware in a single language. I believe Bluespec is similar to Haskell, so it might not be too hard for Haskell programmers to pick up. Could argue that Python has similar capabilities, perhaps PyHDL will move in this direction too.
The big value add that I see here is that the management of these overlays has traditionally been painful, especially when trying to swap overlays at runtime - this is always sold as one of the big benefits of SoC processor+FPGA, that you can do things like dynamic hardware accelerators based on what software is currently running, but more than some assembly has always been required. This seems like a nice step in the direction of having reasonable mechanisms to reconfigure based on application.
Or do you have to do the overlay switching from an external system?