Adding new Global Routing Algorithm

[taizun-jj202]

Hello,
Just for experimentation purposes, I would like to add a new global routing algorithm to OpenROAD. However I have not worked on OpenROAD before. Is there any documentation that can help me integrate a new algorithm in my local version of OpenROAD before creating a PR with the new algorithm ? Should I be focusing on OpenDB compatiblity with the algorithm ? What flags would i have to set to enable TCL to pick-up that this new algorithm has been implemented ?

Any help would be appreciated, as I am attempting this as a research project!!

[rovinski]

Thanks for your interest!

If you want to get started, you can look at the example tool (exa) as an example of adding a tool to OpenROAD.

I would also recommend viewing the Intro to Physical Design Databases mini-lecture series which has some useful information for getting started. Do note that the method discussed in the series for adding a tool has changed, and that the exa tool should be used instead.

As for contributing the code to OpenROAD, because OpenROAD already has a global router (technically two, with CUGR), there would be a higher bar for contribution. It would likely have to pass all of the OpenROAD regression tests and also prove to be superior to the current global routers in terms of quality of results.

[taizun-jj202]

Thank you for the response! I am new to EDA development, so I will go through the materials that you have provided before any attempts. The global router integration is just an exercise for me to get familiar with the OpenROAD code base. The global router in question is SPRoute2.0 which from the published results is faster. However my main goal is to get familiar with OpenROAD and I would perform all regression tests as a practice for another algorithm that I am developing!

[maliberty]

Do you want to preview the approach you are thinking about?

[taizun-jj202]

As mentioned, my main goal is getting familiar with the OpenROAD codebase and integrating global routing tools into OpenROAD. I am developing a new global router as a part of my Master's thesis where the knowledge on tool integration would be handy.

[maliberty]

Welcome aboard.

[taizun-jj202]

Hello,
I have integrated the new Global Routing algorithm in my local copy of OpenROAD. What tests should I run to test integration and verify functionality ? I have only modified the global routing stage in OpenROAD, the rest of the source code remains unchanged.

[maliberty]

You can run any of the designs in ORFS if you modify the flow to use your router.

[taizun-jj202]

Hello,
So I have completed integrating a new global router into my local installation of OpenROAD.
According to the new tool integration guidlines in the exa folder, any new tool should be in its separate folder under src. However, since this is a new global router, should I integrate this as a new tool with a separate folder under src or should the new algorithm be a sub-folder under src/grt which is where the current Global Routers are integrated ?

[maliberty]

Under grt would make sense as we already have FastRoute and CUGR there