Getting Started with OpenROAD Flow¶
OpenROAD Flow is a full RTL-to-GDS flow built entirely on open-source tools. The project aims for automated, no-human-in-the-loop digital circuit design with 24-hour turnaround time.
Setup¶
System Requirements¶
To build the binaries and run gcd through the flow:
Minimum: 1 CPU core and 4GB RAM.
Recommend: 4 CPU cores and 16GB of RAM.
NOTE
gcd is a small design, and thus requires less computational power.
Larger designs may require better hardware.
Building and Installing the Software¶
There are currently two options to set up the OpenROAD Flow:
Build from sources using Docker, instructions here.
Build from sources locally, instructions here.
Running a Design¶
Sample design configurations are available in the designs directory.
You can select a design using either of the following methods:
The flow Makefile contains a list of sample design configurations at the top of the file. Uncomment the respective line to select the design.
Specify the design using the shell environment. For example:
make DESIGN_CONFIG=./designs/nangate45/swerv/config.mk
# or
export DESIGN_CONFIG=./designs/nangate45/swerv/config.mk
make
By default, the gcd design is selected using the
nangate45 platform. The resulting GDS will be available at
flow/results/nangate45/gcd/6_final.gds. The flow should take only a few
minutes to produce a GDS for this design. We recommend implementing this
design first to validate your flow and tool setup.
Adding a New Design¶
To add a new design, we recommend looking at the included designs for examples of how to set one up.
Platforms¶
OpenROAD-flow-scripts supports Verilog to GDS for the following open platforms:
ASAP7
Nangate45 / FreePDK45
SKY130
These platforms have a permissive license which allows us to
redistribute the PDK and OpenROAD platform-specific files. The platform
files and license(s) are located in platforms/{platform}.
OpenROAD-flow-scripts also supports the following commercial platforms:
GF12
TSMC65LP
The PDKs and platform-specific files for these kits cannot be provided due to NDA restrictions. However, if you are able to access these platforms, you can create the necessary platform-specific files yourself.
Once the platform is set up, you can create a new design configuration with
information about the design. See sample configurations in the design
directory.
Adding a New Platform¶
At this time, we recommend looking at the Nangate45 as an example of how to set up a new platform for OpenROAD-flow-scripts.
Implement the Design¶
Run make to perform Verilog to GDS. The final output will be located
at flow/results/{platform}/{design_name}/6_final.gds
Miscellaneous¶
nangate45 smoke-test harness for top-level Verilog designs¶
Drop your Verilog files into designs/src/harness
Start the workflow:
TIP!
Start with a very small submodule in your design that has only a few pins.
make DESIGN_NAME=TopLevelName DESIGN_CONFIG=`pwd`/designs/harness.mk