SKY 130 Chipyard

A SKY 130 tapeout harness built with Chipyard.

BWRC Setup

Install conda (say "yes" and press enter when prompted):

mkdir -m 0700 -p /tools/C/$USER
cd /tools/C/$USER
wget -O Miniforge3.sh \
"https://github.com/conda-forge/miniforge/releases/latest/download/Miniforge3-$(uname)-$(uname -m).sh"
bash Miniforge3.sh -p "/tools/C/${USER}/conda"

Then, run Chipyard setup from the root directory of this repo:

source ~/.bashrc
mamba install -n base conda-lock=1.4
mamba activate base
./build-setup.sh riscv-tools -s 6 -s 7 -s 8 -s 9 -s 10 --force
./scripts/init-vlsi sky130

Add the following to the generated env.sh file:

export PATH=/tools/C/rohankumar/circt/build/bin

To run synthesis, P&R, DRC, and LVS on a TinyRocket in SKY 130:

make syn
make par
make drc
make lvs

Make sure you can view the results and that they look correct (DRC and LVS should be clean).

Development

This harness is currently under development. It is based on the STAC tapeout from June 2023, but aims to be more general-purpose and simple.

Relevant files from STAC:

• SKY 130 Chipyard additions (stac-top/generators/chipyard/src/main/scala/sky130)
• Hammer input files (stac-top/vlsi/design-stac.yml, stac-top/vlsi/tech-sky130.yml)
• Hammer CLI driver (stac-top/vlsi/hammer-driver)
• IO file generator (stac-top/vlsi/scripts/gen-io-file.py)

Files in this harness that will need to be modified/added:

• SKY 130 Chipyard additions (sky130-chipyard/generators/chipyard/src/main/scala/tech/sky130)
• Hammer input file (sky130-chipyard/vlsi/example-sky130-tapeout.yml)
• Hammer CLI driver (sky130-chipyard/vlsi/example-vlsi-sky130-tapeout)

TODOs

• Find better solution to issue where place halo is smaller than power grid blockage
• Get design passing DRC (standard and latchup decks)
• Check whether CDL hack converting generic resistor to short breaks anything