Getting Started¶

OpenROAD is divided into a number of tools that are orchestrated together to achieve RTL-to-GDS. As of the current implementation, the flow is divided into two stages:

Logic Synthesis: is performed by yosys.
Floorplanning through Detailed Routing: are performed by OpenROAD App.

In order to integrate the flow steps, OpenROAD-flow-scripts repository includes the necessary scripts to build and test the flow.

Prerequisites¶

Before proceeding to the next step: 1. Install Docker on your machine, OR 2. Check that build dependencies for all tools are installed on your machine.

During initial Setup or if you have installed on a new machine, run this script: run ./etc/DependencyInstaller.sh

Get the tools¶

There are currently two options to get OpenROAD tools.

Option 1: build from sources using Docker¶

Clone and Build¶

$ git clone --recursive https://github.com/The-OpenROAD-Project/OpenROAD-flow-scripts
$ cd OpenROAD-flow-scripts
$ ./build_openroad.sh

Verify Installation¶

The binaries should be available on your $PATH after setting up the environment.

$ docker run -it -u $(id -u ${USER}):$(id -g ${USER}) -v $(pwd)/flow/platforms:/OpenROAD-flow-scripts/flow/platforms:ro openroad/flow-scripts
[inside docker] $ source ./setup_env.sh
[inside docker] $ yosys -help
[inside docker] $ openroad -help
[inside docker] $ cd flow
[inside docker] $ make
[inside docker] $ exit

Option 2: Build from sources locally¶

Clone and Build¶

$ git clone --recursive https://github.com/The-OpenROAD-Project/OpenROAD-flow-scripts
$ cd OpenROAD-flow-scripts
$ ./build_openroad.sh --local

Verify Installation¶

The binaries should be available on your $PATH after setting up the environment.

$ source ./setup_env.sh
$ yosys -help
$ openroad -help
$ exit

Designs¶

Sample design configurations are available in the designs directory. You can select a design using either of the following methods:

1. The flow Makefile contains a list of sample design configurations at the top of the file. Uncomment the respective line to select the design 2. Specify the design using the shell environment, e.g. make DESIGN_CONFIG=./designs/nangate45/swerv/config.mk or export DESIGN_CONFIG=./designs/nangate45/swerv/config.mk ; make

By default, the simple design gcd is selected. 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: Nangate45 / FreePDK45

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: TSMC65LP / GF14 (in progress)

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 setup. 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¶

tiny-tests - easy to add, single concern, single Verilog file¶

The tiny-tests are have been designed with two design goals in mind:

It should be trivial to add a new test: simply add a tiny standalone Verilog file to OpenROAD-flow-scripts/flow/designs/src/tiny-tests
Each test should be as small and as standalone as possible and be a single concern test.

To run a test:

make DESIGN_NAME=SmallPinCount DESIGN_CONFIG=`pwd`/designs/tiny-tests.mk

nangate45 smoke-test harness for top level Verilog designs¶

Drop your Verilog files into designs/src/harness
Start the workflow:

make DESIGN_NAME=TopLevelName DESIGN_CONFIG=`pwd`/designs/harness.mk

Note

TIP! Start with a small tiny submodule in your design with few pins