Buildroot training course updated to Buildroot 2017.08

BuildrootBack in June 2015, we announced the availability of a training course on Buildroot, a popular and easy to use embedded Linux build system. A year later, we updated it to cover Buildroot 2016.05. We are happy to announce a new update: we now cover Buildroot 2017.08.

The most significant updates are:

  • Presentation of the Long Term Supported releases of Buildroot, a topic we also presented in a previous blog post
  • Appearance of the new top-level utils/ directory, containing various utilities directly useful for the Buildroot user, such as test-pkg, check-package, get-developers or scanpypi
  • Removal of $(HOST_DIR)/usr/, as everything has been moved up one level to $(HOST_DIR), to make the Buildroot SDK/toolchain more conventional
  • Document the new organization of the skeleton package, now split into several packages, to properly support various init systems. A new diagram has been added to clarify this topic.
  • List all package infrastructures that are available in Buildroot, since their number is growing!
  • Use SPDX license codes for licensing information in packages, which is now mandatory in Buildroot
  • Remove the indication that dependencies of host (i.e native) packages are derived from the dependencies of the corresponding package, since it’s no longer the case
  • Indicate that the check for hashes has been extended to also allow checking the hash of license files. This allows to detect changes in the license text.
  • Update the BR2_EXTERNAL presentation to cover the fact that multiples BR2_EXTERNAL trees are supported now.
  • Use the new relocatable SDK functionality that appeared in Buildroot 2017.08.

The practical labs have of course been updated to use Buildroot 2017.08, but also Linux 4.13 and U-Boot 2017.07, to remain current with upstream versions. In addition, they have been extended with two additional steps:

  • Booting the Buildroot generated system using TFTP and NFS, as an alternative to the SD card we normally use
  • Using genimage to generate a complete and ready to flash SD card image

We will be delivering this course to one of our customers in Germany next month, and are of course available to deliver it on-site anywhere in the world if you’re interested! And of course, we continue to publish, for free, all the materials used in this training session: slides and labs.

Yocto project and OpenEmbedded training updated to Krogoth


Continuing our efforts to keep our training materials up-to-date we just refreshed our Yocto project and OpenEmbedded training course to the latest Yocto project release, Krogoth (2.1.1). In addition to adapting our training labs to the Krogoth release, we improved our training materials to cover more aspects and new features.

The most important changes are:

  • New chapter about devtool, the new utility from the Yocto project to improve the developers’ workflow to integrate a package into the build system or to make patches to existing packages.
  • Improve the distro layers slides to add configuration samples and give advice on how to use these layers.
  • Add a part about quilt to easily patch already supported packages.
  • Explain in depth how file inclusions are handled by BitBake.
  • Improve the description about tasks by adding slides on how to write them in Python.

The updated training materials are available on our training page: agenda (PDF), slides (PDF) and labs (PDF).

Join our Yocto specialist Alexandre Belloni for the first public session of this improved training in Lyon (France) on October 19-21. We are also available to deliver this training worldwide at your site, contact us!

Free seat in Android training session

Student penguinsAt Free Electrons, we owe a lot to the Free Software community, and we’re doing our best to give back as much as we can.

One way of doing that is welcoming community contributors in our public training sessions about embedded Linux, Linux kernel and Android system development organized in France. We’ve done that multiple times in the past, and this allowed us to meet very interesting people (who even had very valuable experience and points of view to share with the other course participants), while of course giving them extra knowledge that they can use for further contributions.

The next session in which we can offer a free seat is about Android system development, and will take place on June 20-23 in Toulouse, France. The session has a value of 1890 EUR (without V.A.T.) and includes lunch and breaks, as well as a free Beaglebone Black board with its 4.3″ LCD touchscreen cape.

This course will teach you how to modify Android to support a new embedded board (assuming that it is already supported by the Linux kernel), and how to build a real system through accessing specific hardware, customizing the filesystem and using debugging techniques.

How to apply?

  • You need to be a student or a contributor to a free software project, which doesn’t have to be related to the embedded field, and even if your contributions are modest.
  • Write to before May. 30 and tell us about your contributions and your interest in the session.
  • Thomas Petazzoni and Michael Opdenacker will review all the proposals and will select the candidate who best stands out in terms of past contributions and/or in potential for further ones after taking the course. Free Electrons reserves the right not to select any candidate if nobody actually makes a sufficiently interesting application.
  • The winner will be notified by June 2, and will have to be ready to travel to Toulouse and stay there the whole 4 days at her/his own expense.

Don’t hesitate to apply to this free seat. In past editions, we didn’t have so many people applying, and therefore you have a real chance to get selected!

Embedded Linux Development with Yocto Project

Embedded Linux Development with Yocto Project Cover

We were kindly provided a copy of Embedded Linux Development with Yocto Project, written by Otavio Salvador and Daiane Angolini. It is available at Packt Publishing, either in an electronic format (DRM free) or printed.

This book will help you start with your embedded system development and integration using the Yocto Project or OpenEmbedded.

The first chapter sheds some light on the meaning of commonly misused names: Yocto Project, Poky, OpenEmbedded, BitBake. Then, it doesn’t waste time and explains how to install and use Poky to build and then run an image. The entire book is full of examples that can easily be tested, providing useful hands-on experience, using Yocto Project 1.6 (Poky 11).

The following chapters cover:

  • Hob: a user friendly interface, however, it will soon be deprecated and replaced by Toaster.
  • BitBake and Metadata: how to use BitBake, how to write recipes for packages or images, how to extend existing recipes, how to write new classes, how to create a layer, where to find existing layers and use them.
  • The build directory layout: what the generated files are, and what their use is.
  • Packaging: how to generate different package formats, how to handle a package feed and the package versions.
  • The various SDKs that can be generated and their integration in Eclipse.
  • Debugging the metadata: what the common issues are, how to find what is going wrong, and solving these issues.
  • Debugging the applications on the target: how to generate an image with debugging tools installed.
  • Available tools to help achieve copyleft compliance: in particular, how to cope with the GPL requirements.

Finally, there is a chapter dedicated to explaining how to generate and run an image on the Wandboard, an i.MX6 based community board.

The book is easy to read, with plenty of examples and useful tips. It requires some knowledge about generic embedded Linux system development (see our training) as only the Yocto Project specifics are covered. I would recommend it both for beginners wanting to learn about the Yocto Project and for developers wanting to improve their current knowledge and their recipes and also understand the BitBake internals.

Speaking of the Yocto Project, it is worth noting that Free Electrons is now offering a Yocto Project and OpenEmbedded training course (detailed agenda). If you’re interested, join one of the upcoming public training sessions, or order a session at your location!

Embedded Linux training update: Atmel Xplained, and more!

Atmel SAMA5D3 Xplained boardWe are happy to announce that we have published a significant update of our Embedded Linux training course. As all our training materials, this update is freely available for everyone, under a Creative Commons (CC-BY-SA) license.

This update brings the following major improvements to the training session:

  • The hardware platform used for all the practical labs is the Atmel SAMA5D3 Xplained platform, a popular platform that features the ARMv7 compatible Atmel SAMA5D3 processor on a board with expansion headers compatible with Arduino shields. The fact that the platform is very well supported by the mainline Linux kernel, and the easy access to a wide range of Arduino shields makes it a very useful prototyping platform for many projects. Of course, as usual, participants to our public training sessions keep their board after the end of the course! Note we continue to support the IGEPv2 board from ISEE for customers who prefer this option.
  • The practical labs that consist in Cross-compiling third party libraries and applications and Working with Buildroot now use a USB audio device connected to the Xplained board on the hardware side, and various audio libraries/applications on the software side. This replaces our previous labs which were using DirectFB as an example of a graphical library used in a system emulated under QEMU. We indeed believe that practical labs on real hardware are much more interesting and exciting.
  • Many updates were made to various software components used in the training session: the toolchain components were all updated and we now use a hard float toolchain, more recent U-Boot and Linux kernel versions are used, etc.

The training materials are available as pre-compiled PDF (slides, labs, agenda), but their source code in also available in our Git repository.

If you are interested in this training session, see the dates of our public training sessions, or order one to be held at your location. Do not hesitate to contact us at for further details!

It is worth mentioning that for the purpose of the development of this training session, we did a few contributions to open-source projects:

Thanks a lot to our engineers Maxime Ripard and Alexandre Belloni, who worked on this major update of our training session.

Android training sessions in the UK

Free Electrons is happy to announce its first public training session outside of France.

British Android robot logo

Of course, we deliver training courses on customer sites all around the world, but this will be the first one open to individual registration that we organize outside of France.

We are starting with an Android system development session in Southampton, UK.

You will enjoy the newest version of our Android course, based on Android 4.x, and using the BeagleBone Black as the development platform for the practical labs. As always in our training sessions, participants walk away with the board used during the practical labs (in this case the BeagleBone Black and its LCD cape), allowing them to continue their learning and experiments well after the end of the course.

Being a popular cruising destination, Southampton is easy to reach from other cities in the UK and in the world.

The Android robot picture is copyrighted by Google. It is licensed under the Creative Commons 3.0 Attribution Unported license. The British robot version has been derived by Free Electrons, and is available under the same license. Feel free to reuse it and improve it as long as you keep the original author!

New training materials: boot time reduction workshop

We are happy to release new training materials that we have developed in 2013 with funding from Atmel Corporation.

The materials correspond to a 1-day embedded Linux boot time reduction workshop. In addition to boot time reduction theory, consolidating some of our experience from our embedded Linux boot time reduction projects, the workshop allows participants to practice with the most common techniques. This is done on SAMA5D3x Evaluation Kits from Atmel.

The system to optimize is a video demo from Atmel. We reduce the time to start a GStreamer based video player. During the practical labs, you will practice with techniques to:

  • Measure the various steps of the boot process
  • Analyze time spent starting system services, using bootchartd
  • Simplify your init scripts
  • Trace application startup with strace
  • Find kernel functions taking the most time during the boot process
  • Reduce kernel size and boot time
  • Replace U-Boot by the Barebox bootloader, and save a lot of time
    thanks to the activation of the data cache.

Creative commonsAs usual, our training materials are available under the terms of the Creative Commons Attribution-ShareAlike 3.0 license. This essentially means that you are free to download, distribute and even modify them, provided you mention us as the original authors and that you share these documents under the same conditions.

Special thanks to Atmel for allowing us to share these new materials under this license!

Here are the documents at last:

The first public session of this workshop will be announced in the next weeks.
Don’t hesitate to contact us if you are interested in organizing a session on your site.

Updated version of our kernel driver development course: Device Tree, BeagleBone Black, Wii Nunchuk, and more!

BeagleBone Black connected to the Wii Nunchuk over I2C
In the last few years, the practical labs of our Embedded Linux kernel and driver development training were based on the ARMv5 Calao USB-A9263 platform, and covering the ARM kernel support as it was a few years ago. While we do regularly update our training session materials, with all the changes that occurred in the ARM kernel world over the last two years, it was time to make more radical changes to this training course. This update is now available since last month, and we’ve already successfully given several sessions of this updated course.

The major improvements and updates are:

  • All the practical labs are now done on the highly popular ARMv7 based BeagleBone Black, which offers much more expansion capabilities than the Calao USB-A9263 platform we were using. This also means that participants to our public training sessions keep the BeagleBone Black with them after the session!
  • All the course materials and practical labs were updated to cover and use the Device Tree mechanism. We also for example cover how to configure pin muxing on the BeagleBone Black through the Device Tree.
  • The training course is now centered around the development of two device drivers:
    1. A driver for the Wii Nunchuk. This device is connected over I2C to the BeagleBone Black, and we detail, step by step, how to write a driver that communicates over I2C with the device and then exposes the device functionalities to userspace through the input kernel subsystem.
    2. A minimal driver for the OMAP UART, which we use to illustrate how to interface with memory-mapped devices: mapping I/O registers, accessing them, handling interrupts, putting processes to sleep and waking them up, etc. We expose some minimal functionality of the device to userspace through the misc kernel subsystem. This subsystem is useful to expose the functionalities of non-standard types of devices, such as custom devices implemented inside FPGAs.

And as usual, all the training materials are freely available, under a Creative Commons license, so you can study in detail the contents of the training session. It is also worth mentioning that this training session is taught by Free Electrons engineers having practical and visible experience in kernel development, as can be seen in the contributions we made in the latest kernel releases: 3.9, 3.10, 3.11 and 3.12.

For details about cost and registration, see our Training cost and registration page.

Announcing our “Android System Development” training

Android RobotFor multiple years, Free Electrons has provided two typical training courses for embedded Linux developers: an Embedded Linux system development course that focuses on the basics for embedded Linux development (bootloader and kernel configuration, compiling and usage, system integration and build systems, cross-compiling, filesystems, application development and debugging, etc.) and an embedded Linux kernel and driver development course that focuses on kernel and driver development (kernel APIs for drivers, character drivers, device model, power management, kernel porting, etc.). In total, we have given dozens of editions of these sessions in multiple locations all around the world. We have kept our commitment to release all the training materials under a free license (the Creative Commons CC-BY-SA license), and they are therefore freely accessible for anyone at /docs/.

We are now announcing a new course, called Android System Development. It is a four day training session that targets engineers who need to develop embedded systems with Google Android.

Through theory and practical labs, the course makes you familiar with compiling and booting Android, with adapting Android to support a new embedded board (assuming that it is already supported by the Linux kernel), and with building a real system through accessing specific hardware, customizing the filesystem and using debugging techniques. See the complete agenda. The training materials for this session will also be made available under the same Creative Commons CC-BY-SA license.

If you are interested in this training session, you can:

  • Join the public session organized in Toulouse, France, on June 11-14, 2012.
  • Order an on-site training session to be held at your location. See registration details.

This training course will be given by our engineer Maxime Ripard who has gained Android experience by working at Archos on Android tablets, by making Android work on multiple TI OMAP3 based platforms and also by participating to the Android Builders Summit conference.

Do not hesitate to contact us for further details about this new training course.

Embedded Linux Opportunities – Keynote in Eindhoven

Fontys UniversityIf you live near Eindhoven in the Netherlands, or if you can easily get there, you may be interested in the seminar organized by Fontys University on June 25, 2010.

I will be in Eindhoven on that week to give our Embedded Linux System Development course. The session is organized by Fontys University and Alten PTS, and Fontys invited me to give a keynote at their seminar on Friday.

The seminar topic is: “Embedded Linux for SMEs” – A guide to professional development:

  • Ruud Ermers (Fontys) – A Guide to professional development
  • Gerben Blom (Alten PTS) – Android for SMEs
  • Michael Opdenacker (Free Electrons) – Embedded Linux Opportunities. Ideas and advise for the Open Minded.
  • The grand race, between arm9 controlled vehicles.
  • Technical demos

Here is the abstract for my speech:

Michael Opdenacker created Free Electrons in 2004, a company that is best known worldwide for the technical resources it shares with the embedded Linux community. The more this company shares (in the true sense of sharing: giving and receiving), the more successful it gets.

That’s why Michael will come to exchange ideas and experience on building successful embeddded Linux systems and businesses. Just make sure you send him a SIGSTOP signal at the end of his timeslot.

To water your mouth, this talk will show a few things which are possible with embedded Linux and free software building blocks. You will see how you can turn an idea into something that could keep you busy during your whole life if you are not careful.

So, if you are in the Eindhoven area, this could be a nice opportunity to meet. I hope to see you there!