New macro integration method

[mole99]

Description

I would like to try another macro integration method that I read about here: The-OpenROAD-Project/OpenROAD#215 (comment)

If the macros and the top-level have the same PDN configuration and the macros are properly aligned, the vertical stripes could - in theorie - just be connected.

Therefore I have adjusted OpenLane2's PDN script to pass -extend_to_boundary to add_pdn_stripe.

The PDN stripes of the macros now extend all the way to the boundary and the macros are aligned with the top-level's PDN, but still they don't connect:

It seems the top-level PDN stripes don't want to touch the stripes inside the macros even tho they are the same net.

Proposal

Is there a way in OpenLane 2 to make the stripes connect? Or is there a way to extend the macros' PDN stripes even further? (I am not sure if that would help since with the extended stripes, the top-level stripes just stop earlier.)

I can open an issue at OpenROAD's side, but wanted to ask first if anyone here has any ideas :)

If this method works, it could be added to: https://openlane2.readthedocs.io/en/latest/usage/pdn.html

[mole99]

One solution is to place the macros without a gap. The pins and the PDN stripes are aligned and connected without any wiring. For this case it is mostly good:

But still it would be nice if the top-level's vertical PDN stripes were also connect :)

[donn]

@mo-hosni Any ideas?