===== OpenROAD =====

The [[https://theopenroadproject.org/|OpenROAD]] project provides an open source flow from rtl to gds2.

Video: [[https://youtu.be/DuqdMc4Kc3k|Youtube: "OpenROAD - Turning Designs into Optimized Silicon" - Matt Liberty (Latch-Up 2023)]]

IHP Digital Course: [[https://github.com/OS-EDA/Course|IHP Digital Design Course]]

Video: [[https://youtu.be/n-wnvB0LiFE|Youtube: "Die Chipdesigner von morgen gestalten: Open-Source-Initiativen am IHP (C. Wittke, J. Wallenborn)" - OrConf 2025]]

==== Others ====

ETH Zürich has [[https://github.com/pulp-platform/croc|Croc]] as an example used in classes. The project contains a processor and the flow scripts using Bender, Yosys, OpenROAD and KLayout.

They manage the tools setup via [[https://github.com/iic-jku/IIC-OSIC-TOOLS/tree/main|IIC-OSIC-TOOLS]]. That is a collection of install scripts for various tools for a docker image. It is curated by [[https://www.jku.at/en/institute-for-integrated-circuits-and-quantum-computing/about-us/team/univ-prof-dr-harald-pretl/|Harald Pretl]] from the [[https://www.jku.at/en/institute-for-integrated-circuits-and-quantum-computing/|Institute for Integrated Circuits and Quantum Computing]] in Linz.


==== Install ====
The [[https://github.com/The-OpenROAD-Project/OpenROAD|OpenROAD code is available on github]]. OpenROAD provides several install methods like docker, nix, bazel and cmake.

OpenROAD is the tool for the backend part. OpenROAD provides [[https://github.com/The-OpenROAD-Project/OpenROAD-flow-scripts|OpenROAD flow scripts]] which can do the full flow from HDL to GDSII using additional tools like [[https://yosyshq.net/yosys/|YoSys]].

To install all tools for the [[https://openroad-flow-scripts.readthedocs.io/en/latest/tutorials/FlowTutorial.html|OpenROAD flow tutorial]] i have made the [[https://github.com/fredowski/thavlsibuild|THA VLSI build]] script repository.

The following parts are only for the OpenROAD tool.

=== Download the OpenROAD git repository ===

<code>
git clone --recurse-submodules https://github.com/The-OpenROAD-Project/OpenROAD.git
cd OpenROAD
</code>

=== Install via bazel ===

Bazel promises reproducable builds which I liked. I tried it on a virtual (via UTM) debian 13 (trixie) arm64 machine. The openroad binary is a gui application which relies on qt. It seems quite difficult to have system independent gui application. OpenROAD uses prebuild libraries, for example the xcd libraries which are from [[https://github.com/The-OpenROAD-Project/qt_bazel_prebuilts/tree/main/interface_libs|OpenROADS qt_bazel_prebuilts/interface_libs]]. It turns out that prebuild libraries are build in a ubuntu docker container and the copied to the repository. Therefore they are x86_64 and do not work on the arm64 machine.

== Install bazelisk ==

See: https://github.com/bazelbuild/bazelisk/releases/tag/v1.28.1

for the different systems. For debian linux on x86_64 machines do:

<code>
wget https://github.com/bazelbuild/bazelisk/releases/download/v1.28.1/bazelisk-amd64.deb
sudo dpkg -i bazelisk-amd64.deb
</code>


== Build and Run openroad in cmdline mode ==

The will build and run the openroad tool in cmdline mode.
<code>
bazelisk run //:openroad
</code>

== Build and run in gui mode ==

<code>
bazelisk run --//:platform=gui //:openroad -- -gui
</code>

== Run the regression test via bazel ==

The following command will run all tests which are defined in the
src folder. The three dots are real. 
<code>
bazelisk test src/...
</code>

== Run one test from the regression ==

<code>
bazelisk test src/gpl/test:simple01-tcl_test
</code>

== Run the flowtests via bazel ==

<code>
bazelisk test //test:flow_tests --jobs=1
bazelisk test //test:tinyRocket_nangate45-tcl_test
bazelisk test //test:ibex_sky130hs-tcl_test
</code>

=== Install via cmake ===

I stole the following from the [[https://github.com/The-OpenROAD-Project/OpenROAD/blob/master/Dockerfile|Dockerfile]] to build a local version on a debian 12 machine in the lab.

<code>
git clone --recurse-submodules https://github.com/The-OpenROAD-Project/OpenROAD.git
cd OpenROAD
cp etc/DependencyInstaller.sh /tmp
sudo /tmp/DependencyInstaller.sh -ci -base
sudo /tmp/DependencyInstaller.sh -ci -common -save-deps-prefixes=/etc/openroad_deps_prefixes.txt
DEPS_ARGS=$(cat /etc/openroad_deps_prefixes.txt)
echo $DEPS_ARGS
cmake -B build -S . -DCMAKE_BUILD_TYPE=Release -DOPENROAD_VERSION=${fredo} $DEPS_ARGS
cmake --build build -- -j 8

</code>

=== Regression Test ===

To be sure that the compiled tools are actually working as expected on possibly different platforms, a regression test is a good idea. The [[https://github.com/The-OpenROAD-Project/OpenROAD/blob/master/README.md|README.md]] mentions some tests. Run: 

<code>
./test/regression flow
ctest --test-dir build -j 8
</code>


=== Build Results ===

Some collected build results:

[[or_buildresults|OpenROAD Build Results]]