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HI, just a quick question - does "core level" refer to the design top or user_project_wrapper i.e. should my config.tcl for the dut top have pdn related commands for core or for a macro ? I have no mind about whether I want to instantiate my design top as a macro in user_project_wrapper or as an rtl module, I am open to do either ways as specified. Thanks

your design can't be core, it has to be below metal 5 for the power routing to work

I would follow the user_proj_example flow

<@U0172QZ342D> I was trying to search for posts related to openlane's usage of set ::env(DESIGN_IS_CORE) 1 and it lead me to this thread. I am not following the comment about user macros needing to skip metal 5. This is unrelated to the OP's design, but say we have a design with macros containing metal 5 (I have that with MiM caps) -- can't we just obstruct that macro and still get the PDN to go around the obstruction layer? That's what we are hoping to do in the next couple days -- but it would be good to know if that will set off some failing flags, thanks!

I don't think so.  with the current tools, the PDN is just a set of generated wires and you can only really control the pitch and offset. They won't route around any blockage

<@U018LA3KZCJ> has added a new PDN to the latest openlane, which might be cleverer, but I don't know anything about it yet

pdn has always cut wires around blockages.  If you aren't careful you can create a narrow channel that can't be powered but most of the time it works fine.

There is a lot more to what pdn does than just put wires on the pitch/offset grid but it is algorithmic and not user controlled for the most part

note that for macros you generally need to avoid the upper layers so as to leave room for the grid to connect to the power pins from above