cocotb VS chiselverify

The use of cocotb and pyuvm for verification

For FPGA/HDL work, there's cocotb

At the moment, it is not possible to directly simulate synthesizable contexts. In principle, I could add a simulator to CoHDL. As a Python implementation, it would be orders of magnitude slower than other solutions. Instead, I am using Cocotb to validate the generated VHDL and for the unit tests in the GitHub repository. There is also some very, very experimental support for formal verification, but it will take some time for that to become usable.

On the topic of simulation, you don't have to restrict yourself to using Verilog or VHDL to write your test benches. For example, Verilator lets you write them in C++, cocotb lets you use Python, and if you use SpinalHDL you will drive the underlying simulator using Scala.

I know it might be difficult without much context, but this makefile is called by a top level makefile. very confused if lines 35-74 do anything. They seem to be a mix of real makefile syntax and just straight up comments. what do these lines do?

Learn more about this here: https://www.cocotb.org/

Also consider cocotb, this thread has some compelling arguments. I'd say as a student, learning industry tools isn't necessarily the best thing you could spend your time on. Getting fast at design AND verification, where you can maintain flow state and run better microexperiments means you will understand more, faster.

Have you tried looking at the mixed language example?

Chisel is not HLS. It is a Scala library that lets you generate circuits on an RTL abstraction level. That means that you explicitly define every state element like registers and memories. But you can generate N registers inside a loop (or a map/foreach) instead of only 1 at a time. In HLS the compiler needs to somehow infer your registers and memories.

That said, I think one of the problems the google team was struggling with is that in traditional HW development there is design and a separate verification team. The design team bought into Chisel since it would let them generate hardware more quickly, but the verification team just tried to apply their traditional verification methods on the _generated_ Verilog. This is almost like trying to test the assembly that a C++ compiler generates instead of trying to test the C++ program since all your testing infrastructure is setup for testing assembly code and that is "what we have always been doing".

In order to catch verification up to modern Hardware Construction Languages [0] we need more powerful verification libraries that can allow us to build tests that can automatically adapt to the parameters that were supplied to the hardware generator. There are different groups working on this right now. The jury is still out on how to best solver the "verification gap". In case you are interested:

- https://github.com/chiselverify/chiselverify