OpenROAD Flow

OpenROAD-flow-scripts (ORFS) is a fully autonomous, RTL-GDSII flow for rapid architecture and design space exploration, early prediction of QoR and detailed physical design implementation. However, ORFS also enables manual intervention for finer user control of individual flow stages through Tcl commands and Python APIs.

%%{init: { 'logLevel': 'debug', 'theme': 'dark'
  } }%%
timeline
  title RTL-GDSII Using OpenROAD-flow-scripts
  Synthesis
    : Inputs  [RTL, SDC, .lib, .lef]
    : Logic Synthesis  (Yosys)
    : Output files  [Netlist, SDC]
  Floorplan
    : Floorplan Initialization
    : IO placement  (random)
    : Timing-driven mixed-size placement
    : Macro placement
    : Tapcell and welltie insertion
    : PDN generation
  Placement
    : Global placement without placed IOs
    : IO placement  (optimized)
    : Global placement with placed IOs
    : Resizing and buffering
    : Detailed placement
  CTS : Clock Tree Synthesis
    : Timing optimization
    : Filler cell insertion
  Routing
    : Global Routing
    : Detailed Routing
  Finishing
    : Metal Fill insertion
    : Signoff timing report
    : Generate GDSII  (KLayout)
    : DRC/LVS check (KLayout)

Tool Installation

There are multiple ways to install and develop OpenROAD and ORFS. However, the best option depends on your use case, experience level, and personal preference.

Recommendation for new users:
If you are new to OpenROAD-flow-scripts, Docker can be a reliable way to get started since it avoids most dependency and environment issues.

On supported platforms, using the pre-built binaries can be an even simpler option as it avoids building from source.

Alternatively, the Bazel-based flow also avoids manual dependency installation (aside from installing Bazelisk itself), similar to how Docker requires installing Docker.

Use Bazel, avoid installing anything at all and adapt the flow to your needs in your own repository

bazel-orfs provides a seamless, reproducible way to manage dependencies and adapt the flow without requiring manual installations(no Docker images, sudo bash scripts, etc.)

By leveraging Bazel's robust build system, all dependencies are automatically resolved, versioned, and built in a consistent environment. This eliminates setup complexity, ensures fast incremental builds, and allows for easy customization of the flow, making it an efficient choice for both beginners and advanced users.

Docker Based Installation

To ease dependency installation issues, ORFS uses docker images. Docker image includes ORFS binaries, applications as well as all required dependencies. All of the flow tools are encapsulated inside the container image.

If Docker is not installed already, install latest docker tool based on OS from here.

To manage docker as non-root user and verify that you can run docker commands without sudo must complete steps from here.

Build ORFS with Docker

Document for detailed steps on docker based installation found here.

Pre-built Binaries

You can download, set up and run ORFS easily with pre-built binaries, including OpenROAD, Yosys and Klayout. See instructions here.

Thanks to Precision Innovations for providing and supporting OpenROAD based binaries.

Note Only the latest version of OpenROAD is guaranteed to work with the latest version of ORFS.

Disclaimer The versions of OpenROAD, Yosys and Klayout provided by other third-party vendors are not guaranteed to work with ORFS.

Build from sources locally

Document for detailed local build from sources and installation steps found here.

Using the Flow

• For details about the OpenROAD and the available features and individual flows commands, see the documentation here.
• For details about automated flow setup, see ORFS docs here.
• Flow tutorial to run the complete OpenROAD based flow from RTL-GDSII, see the tutorial here.
• To watch ORFS flow tutorial videos, check here.

Building from your own git repository

ORFS supports hosting projects in your own git repository without the need to fork ORFS.

To build from your own git repository:

cd /home/me/myproject
make --file=~/OpenROAD-flow-scripts/flow/Makefile DESIGN_CONFIG=somefolder/config.mk ...

Citing this Work

If you use this software in any published work, we would appreciate a citation! Please use the following references:

@article{ajayi2019openroad,
  title={OpenROAD: Toward a Self-Driving, Open-Source Digital Layout Implementation Tool Chain},
  author={Ajayi, T and Blaauw, D and Chan, TB and Cheng, CK and Chhabria, VA and Choo, DK and Coltella, M and Dobre, S and Dreslinski, R and Foga{\c{c}}a, M and others},
  journal={Proc. GOMACTECH},
  pages={1105--1110},
  year={2019}
}

A copy of this paper is available here (PDF).

@inproceedings{ajayi2019toward,
  title={Toward an open-source digital flow: First learnings from the openroad project},
  author={Ajayi, Tutu and Chhabria, Vidya A and Foga{\c{c}}a, Mateus and Hashemi, Soheil and Hosny, Abdelrahman and Kahng, Andrew B and Kim, Minsoo and Lee, Jeongsup and Mallappa, Uday and Neseem, Marina and others},
  booktitle={Proceedings of the 56th Annual Design Automation Conference 2019},
  pages={1--4},
  year={2019}
}

A copy of this paper is available here (PDF).

If you like the tools, please give us a star on our GitHub repos!

License

The OpenROAD-flow-scripts repository (build and run scripts) has a BSD 3-Clause License. The flow relies on several tools, platforms and designs that each have their own licenses:

• Find the tool license at: OpenROAD-flow-scripts/tools/{tool}/ or OpenROAD-flow-scripts/tools/OpenROAD/src/{tool}/.
• Find the platform license at: OpenROAD-flow-scripts/flow/platforms/{platform}/.
• Find the design license at: OpenROAD-flow-scripts/flow/designs/src/{design}/.