DRC and LVS steps

[stevvik]

Hello!
I have found in documentation? that in ORFS Klayout is used for DRC and LVS steps and decks are available for open PDKs.
In flow Makefile I see drc: and lvs: steps, but they don't run by default and KLAYOUT_DRC_FILE and KLAYOUT_LVS_FILE are not defined.

My questions are:

1. How can I run DRC and LVS steps in ORFS?
2. Where can I get an example of DRC/LVS decks for open PDKs (like sky130) for KLayout?

[maliberty]

This is an incomplete experiment in setting that up for sky130 in the style of OpenLane. For now I would suggest OL for those functions or if you are inclined to contribute you could bring over their setup to ORFS.

[rovinski]

DRC and LVS should still work on nangate45 with make drc and make lvs, respectively. If you want to add support for DRC on a new platform $(PLATFORM):

1. Ensure that a KLayout tech file (.lyt) exists for the platform. If not, create it.
2. Create (or copy) a KLayout .lydrc file at flow/platforms/$(PLATFORM)/drc/$(PLATFORM).lydrc
3. Add the following line to flow/platforms/$(PLATFORM)/config.mk: export KLAYOUT_DRC_FILE = $(PLATFORM_DIR)/drc/$(PLATFORM).lydrc
   You should then be able to run make drc

To add support for LVS:

1. Ensure that a KLayout tech file (.lyt) exists for the platform. If not, create it.
2. Create (or copy) a KLayout .lylvs file at flow/platforms/$(PLATFORM)/lvs/$(PLATFORM).lylvs
3. Add the following line to flow/platforms/$(PLATFORM)/config.mk: export KLAYOUT_LVS_FILE = $(PLATFORM_DIR)/lvs/$(PLATFORM).lylvs
4. Ensure that a CDL file exists for your cell library at flow/platforms/$(PLATFORM)/cdl/$(PLATFORM).cdl. If not, create it.
5. Add the following line to flow/platforms/$(PLATFORM)/config.mk: export CDL_FILE = $(PLATFORM_DIR)/cdl/$(PLATFORM).cdl

You should then be able to run make lvs

[stevvik]

@rovinski , Thank you for the info!
I found KLayout DRC deck for nangate45 platform in ORFS and for sky130A in OpenLane, but I didn't find any LVS deck examle for Klayout. I only see LVS setup for NetGen in OpenLane.
Can you show me the example of KLayout LVS deck for any platform?

[rovinski]

Oh right, I guess the LVS deck did not get uploaded because I couldn't get it to work (probably some combination of settings that need to be set for proper extraction).

@laurentc2 has created several KLayout decks for open PDKs.

• https://github.com/laurentc2/FreePDK45_for_KLayout
• https://github.com/laurentc2/SKY130_for_KLayout
• https://github.com/laurentc2/ASAP7_for_KLayout

You may need to tweak some of the settings in order to get LVS to match. On the other hand, my last trial was more than a year ago so maybe a new version of KLayout will work better.