Setup and installation of Verilator

Note

If you installed the recommended oss-cad-suite during SpinalHDL setup you can skip the instructions below - but you need to activate the oss-cad-suite environment.

SpinalSim + Verilator is supported on both Linux and Windows platforms.

It is recommended that v4.218 is the oldest Verilator version to use. While it maybe possible to use older verilator versions, some optional and Scala source dependent features that SpinalHDL can use (such as Verilog $urandom support) may not be supported by older Verilator versions and will cause an error when trying to simulate.

Ideally the latest v4.xxx and v5.xxx is well supported and bug reports should be opened with any issues you have.

Scala

Don’t forget to add the following in your build.sbt file:

fork := true

And you will always need the following imports in your Scala testbench:

import spinal.core._
import spinal.core.sim._

Linux

You will also need a recent version of Verilator installed :

sudo apt-get install git make autoconf g++ flex bison  # First time prerequisites
git clone http://git.veripool.org/git/verilator   # Only first time
unsetenv VERILATOR_ROOT  # For csh; ignore error if on bash
unset VERILATOR_ROOT  # For bash
cd verilator
git pull             # Make sure we're up-to-date
git checkout v4.218  # Can use newer v4.228 and v5.xxx
autoconf             # Create ./configure script
./configure
make -j$(nproc)
sudo make install
echo "DONE"

Windows

In order to get SpinalSim + Verilator working on Windows, you have to do the following:

Install MSYS2
Via MSYS2 get gcc/g++/verilator (for Verilator you can compile it from the sources)
Add bin and usr\bin of MSYS2 into your windows PATH (ie : C:\msys64\usr\bin;C:\msys64\mingw64\bin)
Check that the JAVA_HOME environment variable points to the JDK installation folder (i.e.: C:\Program Files\Java\jdk-13.0.2)

Then you should be able to run SpinalSim + Verilator from your Scala project without having to use MSYS2 anymore.

From a fresh install of MSYS2 MinGW 64-bit, you will have to run the following commands inside the MSYS2 MinGW 64-bits shell (enter commands one by one):

From the MinGW package manager

pacman -Syuu
# Close the MSYS2 shell once you're asked to
pacman -Syuu
pacman -S --needed base-devel mingw-w64-x86_64-toolchain \
                   git flex\
                   mingw-w64-x86_64-cmake

pacman -U http://repo.msys2.org/mingw/x86_64/mingw-w64-x86_64-verilator-4.032-1-any.pkg.tar.xz

# Add C:\msys64\usr\bin;C:\msys64\mingw64\bin to your Windows PATH

From source

pacman -Syuu
# Close the MSYS2 shell once you're asked to
pacman -Syuu
pacman -S --needed base-devel mingw-w64-x86_64-toolchain \
                   git flex\
                   mingw-w64-x86_64-cmake

git clone http://git.veripool.org/git/verilator
unset VERILATOR_ROOT
cd verilator
git pull
git checkout v4.218   # Can use newer v4.228 and v5.xxx
autoconf
./configure
export CPLUS_INCLUDE_PATH=/usr/include:$CPLUS_INCLUDE_PATH
export PATH=/usr/bin/core_perl:$PATH
cp /usr/include/FlexLexer.h ./src

make -j$(nproc)
make install
echo "DONE"
# Add C:\msys64\usr\bin;C:\msys64\mingw64\bin to your Windows PATH

Important

Be sure that your PATH environnement variable is pointing to the JDK 1.8 and doesn’t contain a JRE installation.

Important

Adding the MSYS2 bin folders into your windows PATH could potentially have some side effects. This is why it is safer to add them as the last elements of the PATH to reduce their priority.