cocotbext-axi VS cocotb

I was hoping to decouple the designs from any particular vendor as much as I could so I would interface with the core (dut) with a Cocotb AXI Lite master to get/set registers. Then if I were using something like an AXI Stream to send/receive audio or video data there was a Cocotb python driver to process the data in the test bench. As an example, in part 5 the graphics core generated a 16x4 color bar image over AXI video stream that was captured by a Cocotb AXI Stream sink and then 'displayed' as hex values in one of the test.

The cocotb bus repo has many of the useful drivers and monitors. https://github.com/cocotb/cocotb-bus/tree/master/src/cocotb_bus. There is also https://github.com/alexforencich/cocotbext-axi for some relevant AXI examples that you can also just use.

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.

Regarding testbenches, they are currently not supported in CoHDL, but you can use Cocotb or any other existing test framework to check the produced VHDL representation.

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.

The only cocotb-supported version of Verilator is 4.106 (see this). But I tried that and quickly ran into issues. I have commercial access to questa sim and the same modules and testbenches worked just fine with that.

I heard about Verilator but it is quite something to learn and I am not sure if its the proper tool for my needs. I have looked into cocotb, but it does not work really well on my side. Could you guys recommend me anything ?

You need an actual test setup. Clone the repo, go to examples, and run make TOPLEVEL_LANG=vhdl SIM=ghdl and see what happens.

CocoTB (Python): I like this python test library. It easy to use, lot's of library to test i2c, uart, wishbone, ... And ... it's Python it's easy ! You can use the simulator you want and even switch between several without big problems. But it's slow simulation even with Verilator (beta) as backend.