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Anton Blanchard

02/14/2022, 10:18 PM
STA in Openlane doesn't appear to incorporate any macro timing information. How are we guaranteeing a design with macros makes timing? Also wondering if OpenROAD supports loading multiple SPEF files.
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Matt Liberty

02/15/2022, 5:14 AM
You need to have a .lib for a macro. For multiple spefs - are you talking about hierarchical stitching or multiple corners?
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Tobias Strauch

02/15/2022, 7:54 AM
So the .lib file IS considered during STA in Openlane automatically ? Thought that this is still worked on. What about the delays at the IOs of the macros ? For example, I don’t see data-in and data-out arcs of SRAMs in the 21-user_proj_example.sdf file.
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Anton Blanchard

02/15/2022, 8:01 AM
@User I'm just fishing around, trying to work out how to do a full STA of my design. I found caravel is doing something similar to what I want: https://github.com/efabless/caravel/blob/main/Makefile#L625
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Matt Liberty

02/15/2022, 4:30 PM
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Anton Blanchard

02/15/2022, 6:53 PM
Thanks @User