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#sky130
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# sky130
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Noah Moroze

05/12/2021, 8:42 PM
Hi all, I’ve been playing around with the various tools out there and was wondering if anyone could shed some light on if there’s anything “special” that OpenLANE does to get DRC clean results for sky130? If I build, for example, the GCD example design in https://github.com/The-OpenROAD-Project/OpenROAD-flow-scripts targeting sky130hd, I get DRC errors. However, it seems like both OpenLANE and the OpenROAD flow scripts are just wrappers over a Yosys->OpenROAD flow, so I’m curious if there’s anything in particular that makes OpenLANE give clean results, while OpenROAD does not (or does it just take a whole bunch of small tweaks combined?)
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Tim Edwards

05/13/2021, 12:48 AM
I should let the developers respond, but to my understanding, it's a lot of tweaks; especially to figure out which standard cell layouts cause the router grief and mark them as unusable.
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Noah Moroze

05/14/2021, 7:24 PM
Ah, that’s a helpful point - it does seem like OpenLANE’s marked a different set of unusable cells from OpenROAD’s demo flow