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Tapcell: Closed Source PDK Feature Request

Open QuantamHD opened this issue 3 years ago • 3 comments

I'm using a PDK + Standard Cell Library that has special end cap cells for both the top, bottom, left and right cells. It also has corner cells for each corner of the macro and core area rectangles (TR, TL, BR, BL). It doesn't seem like tapcell supports this. Can we add this feature?

QuantamHD avatar Jun 08 '22 00:06 QuantamHD

I think it does support them if you look at all the options

maliberty avatar Jun 08 '22 12:06 maliberty

I don't think it does. The tap cell code seems to only allow you to specify top bottom cells whereas this PDK has specialized cells for all 4 sides. The tap cell corner cells are also specialized and it looks like OpenROAD only supports a single corner tap cell type.

image

QuantamHD avatar Jun 08 '22 15:06 QuantamHD

So upon closer inspection it looks like the cells in the PDK are technically named differently, but are really just rotations of each other. I feel like we should probably support the differently named cells, but it's not incorrect per say since OpenROAD seems to be doing to the rotating.

QuantamHD avatar Jun 08 '22 21:06 QuantamHD