The-OpenROAD-Project / The-OpenROAD-Project/OpenROAD-flow-scripts
PDN gen appears to silently ignore -starts_with in define_pdn_grid
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@gadfort is already working on this.
Since Jun 24, 2026.
pdn
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Description
Subject
Describe the bug
Found with proprietary PDK, but repro's with ASAP7 PDK
If the ASAP7 PDN gen script is updated from:
define_pdn_grid -name {top} -voltage_domains {CORE} -pins {M6}
to:
define_pdn_grid -name {top} -voltage_domains {CORE} -pins {M6} -starts_with POWER
Shouldn't the bottom-most M1 rail be VDD and not VSS? It's not:
Expected Behavior
If the -starts_with is ignored for some reason, we might want to log it and why.
Environment
orfs git commit tag: c9c22caf9bf9cfe46c5a4236c6ec7e7ae9863cc3
To Reproduce
mkissue tarball: https://drive.google.com/file/d/1nWdbR5GFE3S2eBDfHjN5aCBOEunPQA_r/view?usp=drive_link
Relevant log output
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Additional Context
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