A generic TCP socket server interface for Icarus with VPI - Request for feedback

[jchabloz]

I have been using Icarus for quite some time now, in all sorts of contexts. Lately, I have been wanting to find a solution to better automatize verification tasks (typically integration tests) with high-level test automation frameworks, my first choices going to Python tools, such as e.g. the robot framework or pytest.

I have been playing a bit with cocotb, however, even though this is working really nicely, it did not really fit my purpose since cocotb uses its own so-called "regression manager", and to be honest, this removes most of the control I desire to have when writing test cases. There are some workarounds, such as cocotb-test, which enables to use pytest with cocotb, but, mmh, it adds a lot of complexity to something which should be simpler...

I wanted to try an alternative, and came up with the following proposal; use the Icarus VPI interface and create a simple server accepting TCP socket connections to receive commands to control the simulation, force and read values, etc... I have now a first running version of this proposal, which I named "Verisocks" and that you can find here: https://github.com/jchabloz/verisocks.

What I have:

• Full set of VPI routines that sets up a TCP socket server and commands
• Python client with its own test suite using pytest, that serves as well as a pretty complete example
• As of today, one example of using Verisocks to drive transactions on an SPI bus

What I don't have yet

• Unit testing of the VPI routines (work in progress)
• Detailed documentation
• A more portable compilation flow for the VPI routines lib (still need to edit manually the Makefile...)

What I believe to be nice with Verisocks is

• you can interface your Icarus with any tool you'd like, as long as it is able to use TCP sockets
• it is extremely easy to use; you just need to launch it with a simple user task in your top verilog testbench code
• you do not need to change anything in the way you are using Icarus

I would really appreciate if some persons in the community would take the time to check it out and let me know about any comments, pieces of advice, feedback, questions, etc. I will do my best to support anybody who is willing to spend some of her/his time to help me improve it!

[red0bear]

i think using only VPI with C++ , systemC , integration better with system verilog UVM could be very good addition to icarus verilog.

[jchabloz]

Dear community,

Before I close this topic for good if there is no interest, I am happy to let you know that I finally ended up releasing a version 1.0.0 of the VPI module development, including detailed documentation for the implemented TCP protocol and Python client.
So far it has been tested and is working perfectly on Ubuntu 20.04, Ubuntu 22.04, Cygwin x86_64 and various versions of Red Hat Enterprise.

You can find the github repo here: https://github.com/jchabloz/verisocks
You can find the documentation here: https://jchabloz.github.io/verisocks

I would be extremely happy to get any feedback and advice and will support.