IHP platform May 2024 update

[KrzysztofHerman]

1. IO cells added LIB (corners), LEF, GDS, Verilog
2. update script sg13g2-update.py added. Execute te following command in platforms/ihp-sg13g2

   python sg13g2-update.py

3. fixes to standard cells provided
4. cdl netlists for SRAM updated with native names of the mos devices
5. DRC ruledeck updated
6. bondpad LEF and GDS 77x70 added
7. All corners for LIBERTY views for standard cells covered. wire_load statement used for wire load modeling

[dnltz]

Hey @KrzysztofHerman can you please update platforms/ihp-sg13g2/config.mk as well?

I had to extend following exports in my desgin's config.mk:

export ADDITIONAL_LEFS = \
    ./platforms/$(PLATFORM)/lef/sg13g2_io.lef \
    ./platforms/$(PLATFORM)/lef/bondpad_70x70.lef
export ADDITIONAL_GDS = \
    ./platforms/$(PLATFORM)/gds/sg13g2_io.gds \
    ./platforms/$(PLATFORM)/gds/bondpad_70x70.gds
export ADDITIONAL_LIBS = \
    ./platforms/$(PLATFORM)/lib/sg13g2_io_dummy.lib

BTW: sg13g2_io.v got parsed and it's not required to define this anywhere.

[KrzysztofHerman]

@dnltz as for the IO related views and the possible extension of the main IHP's platform config file I think it would be better to provide a well documented example of a pad ring generation together with all additional files. Thus we will avoid messing with not used files included in default designs. Maybe @maliberty and @rovinski could suggest what would be better ?

[dnltz]

@KrzysztofHerman okay makes sense. Seems like only the sky130 coyote_tc design has some IO definitions. So, maybe too early.

[rovinski]

Having an example design with I/O cells is never a bad idea.

[maliberty]

Note that there was an IHP update in https://github.com/The-OpenROAD-Project/OpenROAD-flow-scripts/pull/2066. As this PR is older I want to ensure we aren't moving backwards on any files.