TinyTapeout

See https://tinytapeout.com for more information on the project and how to get involved.

Instructions to build

Fetch all the projects

./configure --update-projects

Configure Caravel

./configure --update-caravel

Build the GDS

make user_project_wrapper

Dev notes

• PDN hang issues https://github.com/The-OpenROAD-Project/OpenLane/issues/1173
• Also discovered PDN hangs if extra lefs/defs are not deduplicated
• with PDN set so dense, tapeout job fails with density checks
• with unused PDN straps turned off, precheck fails
• copied the erased version (just power rings) and deleted the first digital power rings, copy pasted that over final gds
• precheck fails with missing power ports
• manually added missing power ports to gl verilog of user_project_wrapper
• precheck passes. Will try tapeout job
• tapeout job failed with DRC, was because outer power ring was too thin. I think due to configuration rather than being cutoff for precheck
• updated missing_power_rings with correct rings and repeated, this time tapeout passes
• Tim suggests doing this as a module/cell to make it easier to reproduce
• Maximo suggests editing pdn_cfg.tcl and using the -nets option with add_pdn_stripe to force only 1st voltage domain
• This worked, see the new openlane/user_project_wrapper/pdn_cfg.tcl config