Hello everyone ! I was following the Floorplanning tutorial for siliconcompiler (https://docs.siliconcompiler.com/en/latest/tutorials/zerosoc.html#minimal-chip-configuration) which mention

FILL_CELLS = ['sky130_ef_io__com_bus_slice_1um',
              'sky130_ef_io__com_bus_slice_5um',
              'sky130_ef_io__com_bus_slice_10um',
              'sky130_ef_io__com_bus_slice_20um']

which, I believe, are the cells used to build the padring between IOs. As the tutorial seems to use a dummy lib (

sky130_dummy_io.lib

) I wanted to try with the actual PDK and I found mention of padring corners with

./libraries/sky130_fd_io/latest/cells/corner_bus_overlay
./libraries/sky130_fd_io/latest/cells/corner_bus_overlay/sky130_fd_io__corner_bus_overlay.gds

but nothing about actual slices within the PDK. Is this to be expected ?

Files in the path

skywater-pdk/libraries

are all directly from the Google/SkyWater open source PDK repository. The cells you mention are efabless libraries that provide missing functionality and fill in gaps in the open source PDK. Those cells are part of the

open_pdks

installer (https://github.com/RTimothyEdwards/open_pdks). Use the

open_pdks

installer to obtain them.

Thanks for the feedback. Just to be sure, is using open_pdks the preferred way to install SKY130 ? (Or is there even a "preferred" way to install it ?)

Yes, using open_pdks is the preferred way to install SKY130.