I’m shifting more and more of my CI/CD testing infrastructure using the LinkServer runner. One reason is the LinkServer runner can run the test on-target. It can also collect GNO gcov coverage information at the same time. LinkServer is a suite of software tools for launching and managing GDB servers for NXP debug probes.

Outline

In my CI/CD pipeline, I’m using GitHub, GitLab plus Docker running an Ubuntu container. The container image installs all the necessary tools, including the LinkServer software.

Over the past weeks, I have streamlined the LinkServer software installation. LinkServer as other non-open-software usually asks for a license agreement, for example with a click-through license agreement. In a CI/CD environment, no user intervention is desired. So special command line options have been used to automate the process.

Starting Point

Below is an extract from the docker image I have been used for over a year now:

# Install LinkServer software: make sure you have the same version installed on your host!
RUN \
  apt-get install -y whiptail libusb-1.0-0-dev dfu-util usbutils hwdata
# Linkserver download paths, e.g.
# Windows: https://www.nxp.com/lgfiles/updates/mcuxpresso/LinkServer_24.9.75.exe
# Linux: https://www.nxp.com/lgfiles/updates/mcuxpresso/LinkServer_24.9.75.x86_64.deb.bin
# MacOS Arch64: https://www.nxp.com/lgfiles/updates/mcuxpresso/LinkServer_24.9.75.aarch64.pkg
# MacOS: https://www.nxp.com/lgfiles/updates/mcuxpresso/LinkServer_24.9.75.x86_64.pkg
RUN \
    cd /project \
    && curl -O https://www.nxp.com/lgfiles/updates/mcuxpresso/LinkServer_24.9.75.x86_64.deb.bin \
    && chmod a+x LinkServer_24.9.75.x86_64.deb.bin \
    && ./LinkServer_24.9.75.x86_64.deb.bin --noexec --target linkserver \
    && cd linkserver \
    && dpkg --unpack LinkServer_24.9.75.x86_64.deb \
    && rm /var/lib/dpkg/info/linkserver_24.9.75.postinst \
    && dpkg --configure linkserver_24.9.75 \
    && dpkg --unpack LPCScrypt.deb \
    && rm /var/lib/dpkg/info/lpcscrypt.postinst \
    && apt-get install -yf

It works fine and does not ask for any user input. It allows me to pick a specific version of the LinkServer software which is great. But the version number information is duplicated throughout the script.

The first improvement was to use a variable, so the version number can be specified in on e location. In Docker files, this can be done with an ARG.

Using ARG

With using ARG, I can create and use a runtime variable for Docker during the image build.

ARG LINKSERVER_VERSION="25.7.33"

With this I specify which version of LinkServer I want to use. Inside the script I can use it like this:

LinkServer_${LINKSERVER_VERSION}.x86_64.deb.bin

Now the script looks much better:

# Install LinkServer software: make sure you have the same version installed on your host!
ARG LINKSERVER_VERSION="25.7.33"
RUN \
  apt-get install -y whiptail libusb-1.0-0-dev dfu-util usbutils hwdata
# Linkserver download paths, e.g.
# Windows: https://www.nxp.com/lgfiles/updates/mcuxpresso/LinkServer_${LINKSERVER_VERSION}.exe
# Linux: https://www.nxp.com/lgfiles/updates/mcuxpresso/LinkServer_${LINKSERVER_VERSION}.x86_64.deb.bin
# MacOS Arch64: https://www.nxp.com/lgfiles/updates/mcuxpresso/LinkServer_${LINKSERVER_VERSION}.aarch64.pkg
# MacOS: https://www.nxp.com/lgfiles/updates/mcuxpresso/LinkServer_${LINKSERVER_VERSION}.x86_64.pkg
RUN \
    cd /project \
    && curl -O https://www.nxp.com/lgfiles/updates/mcuxpresso/LinkServer_${LINKSERVER_VERSION}.x86_64.deb.bin \
    && chmod a+x LinkServer_${LINKSERVER_VERSION}.x86_64.deb.bin \
    && ./LinkServer_${LINKSERVER_VERSION}.x86_64.deb.bin --noexec --target linkserver \
    && cd linkserver \
    && dpkg --unpack LinkServer_${LINKSERVER_VERSION}.x86_64.deb \
    && rm /var/lib/dpkg/info/linkserver_${LINKSERVER_VERSION}.postinst \
    && dpkg --configure linkserver_${LINKSERVER_VERSION} \
    && dpkg --unpack LPCScrypt.deb \
    && rm /var/lib/dpkg/info/lpcscrypt.postinst \
    && apt-get install -yf

Still, that installation script does a lot of tweaking of the installation process.

acceptLicense & skipIdeSelect

In my above script, I first unpack the archive into the ‘linkserver’ folder:

./LinkServer_${LINKSERVER_VERSION}.x86_64.deb.bin --noexec --target linkserver

The installer has two interactive parts. One is accepting the license agreement. Plus in newer installations it asks if MCUXpresso IDE’s shall be updated.

Looking through the linkserver/install.sh script I can see that there are options to skip them:

if [ $# -gt 0 ]; then
    for arg in "$@" 
    do
        if [ "$arg" == "acceptLicense" ]; then
            ACCEPT_LICENSE=1
        fi
        if [ "$arg" == "skipIdeSelect" ]; then
            SKIP_IDE_SELECT=1
        fi
    done
fi

So instead unpacking the archive and script modifications, I can do what I want directly with:

./LinkServer_${LINKSERVER_VERSION}.x86_64.deb.bin acceptLicense skipIdeSelect

Not working?

But doing this, I noticed that I had strange error messages:

"Failed to send reload request: No such file or directory"

After some searching, I have found out that this is related to the udev service. In my docker image case, udev has not been started, so I had to add this to the script:

/lib/systemd/systemd-udevd --daemon

Final Version

Finally everything comes together:

# which version to use:
ARG LINKSERVER_VERSION="25.7.33"

# install dependencies: need to start udev manually, otherwise getting "Failed to send reload request: No such file or directory" during LinkServer installation
RUN \
    apt-get install -y whiptail libusb-1.0-0-dev dfu-util usbutils hwdata \
    && /lib/systemd/systemd-udevd --daemon

# install LinkServer software
RUN \
    curl -O https://www.nxp.com/lgfiles/updates/mcuxpresso/LinkServer_${LINKSERVER_VERSION}.x86_64.deb.bin \
    && chmod a+x LinkServer_${LINKSERVER_VERSION}.x86_64.deb.bin \
    && ./LinkServer_${LINKSERVER_VERSION}.x86_64.deb.bin acceptLicense skipIdeSelect

With this, the LinkServer software gets installed without user intervention. And it works fine too for a docker image, tested with Ubuntu 24.04.

Summary

The LinkServer software is a suite of debugging and test running tools for NXP debug probes. In above approach I have streamlined the installation script, requiring less steps and modifications. It works fine in my CI/CD environment using Docker and Linus (Ubuntu).

What is your preferred way to install software, especially for CI/CD? Or what has been your challenges installing software that way? Let me know and post a comment!

Happy installing 🙂

Links

• Project on GitHub: https://github.com/ErichStyger/MCUXpresso_LPC55S16_CI_CD
• NXP LinkServer: https://www.nxp.com/design/design-center/software/development-software/mcuxpresso-software-and-tools-/linkserver-for-microcontrollers:LINKERSERVER
• Running On-Target Tests with Coverage in VS Code
• On-Target Testing with LinkServer Runner and VS Code
• Modern On-Target Embedded System Testing with CMake and CTest
• Optimizing CI/CD with RAM Target Applications