Bootlin at Embedded World 2014, Nuremberg, Germany

Embedded World 2014, Germany

Embedded World is the world’s largest trade show about embedded systems. In 2013, it attracted around 900 exhibitors, over 22,000 visitors and almost 1,500 congress participants.

This year, Bootlin will be represented by our CEO Michael Opdenacker. This should be a great opportunity for us to understand our customers better, by meeting embedded system makers, by seeing what their needs are and what technologies they use. It will also be an opportunity to meet well known members of the technical community. In particular, here are a few well know people who are going to speak at the congress:

Don’t hesitate to contact us if you are attending this event too and are interested in knowing Bootlin better, for business, partnership or even career opportunities!

Buildroot meeting and FOSDEM report, Google Summer of Code topics

As we discussed in a recent blog post, two of our engineers participated to the FOSDEM conference early February in Brussels, Belgium. For those interested, many videos are available, such as several videos from the Lameere room, where the embedded related talks were given.

Thomas Petazzoni also participated to the two days Buildroot Developers Meeting after the FOSDEM conference. This meeting gathered 10 contributors to the Buildroot project physically present and two additional remote participants. The event was sponsored by Google and Mind, thanks a lot to them! During those two days, the participants were able to discuss a very large number of topics that are often difficult to discuss over mailing lists or IRC, and a significant work to clean up the oldest pending patches was done. In addition to this, these meetings are also very important to allow the contributors to know each other, as it makes future online discussions and collaborations much easier and fruitful. For more details, see the complete report of the event.

Buildroot Developers Meeting in Brussels
Buildroot Developers Meeting in Brussels

Also, if you’re interested in Buildroot, the project has applied to participate to the next edition of the Google Summer of Code. Two project ideas are already listed on the project wiki, feel free to contact Thomas Petazzoni if you are a student interested in these topics, or if you have other proposals to make for Buildroot.

Bootlin contributions to Linux 3.13

Version 3.13 of the Linux kernel was released by Linus Torvalds on January, 19th 2014. The kernelnewbies.org site has an excellent page that covers the most important improvements and feature additions that this new kernel release brings.

As usual Bootlin contributed to this kernel: with 121 patches merged in 3.13 on a total of 12127 patches contributed, Bootlin is ranked 17th in the list of companies contributing to the Linux kernel. We also appeared on Jonathan Corbet kernel contribution statistics at LWN.net, as a company having contributed 1% of the kernel changes, right between Renesas Electronics and Huawei Technologies.

Amongst the contributions we made for 3.13:

  • Standby support added to the Marvell Kirkwood processors, done by Ezequiel Garcia.
  • Various fixes and improvements to the PXA3xx NAND driver, as well as to the Marvell Armada 370/XP clocks, in preparation to the introduction of NAND support for Armada 370/XP, which will arrive in 3.14. Work done by Ezequiel Garcia.
  • Added support for the Performance Monitoring Unit in the AM33xx Device Tree files, which allows to use perf and oprofile on platforms such as the BeagleBone. Work done by Alexandre Belloni.
  • Support added for the I2C controllers on certain Allwinner SOCs, as well as several other cleanups and minor improvements for these SoCs. Work done by Maxime Ripard.
  • Continued the work to get rid of IRQF_DISABLED, as well as other janitorial tasks such as removing unused Kconfig symbols. Work done by Michael Opdenacker.
  • Added support for MSI (Message Signaled Interrupts) for the Armada 370 and XP SoCs. Work done by Thomas Petazzoni.
  • Added support for the Marvell Matrix board (an Armada XP based platform) and the OpenBlocks A7 (a Kirkwood based platform manufactured by PlatHome). Work done by Thomas Petazzoni.

In detail, the patches contributed by Bootlin are:

Bootlin at FOSDEM and at the Buildroot Developers Meeting

FOSDEMThis week-end is the first week-end of February, which on the schedule of all open-source developers is always booked for a major event of our community: the FOSDEM conference in Brussels. With several hundreds of talks over two days, this completely free event is one of the biggest event, if not the biggest of the open-source world.

For embedded Linux developers, FOSDEM has quite a few interesting tracks and talks this year: an embedded track, a graphics track (with many embedded related talks, such as talks on Video4Linux, the status of open-source drivers for 2D and 3D graphics on ARM platforms, etc.), and several talks in other tracks relevant to embedded developers. For example, there is one talk about the Allwinner SoCs and the community behind it in one of the main track. Our engineer Maxime Ripard is the Linux kernel maintainer for this family of SoC.

Two Bootlin engineers will attend FOSDEM: Maxime Ripard and Thomas Petazzoni. Do not hesitate to get in touch with them if you want to discuss embedded Linux or kernel topics!

Also, right after FOSDEM, the Buildroot community is organizing its Developers Meeting, on Monday, 3rd and Tuesday 4th February. This event is sponsored by Google (providing the meeting location) and Mind (providing the dinner), and will take place in the offices of Google in Brussels. Ten Buildroot developers will participate to the meeting in Brussels, as well as a number of others remotely. On Bootlin side, Thomas Petazzoni will be participating to the meeting. If you are interested in participating, either physically or remotely, do not hesitate to contact Thomas to register. For more details, see the wiki page of the event.

Android training sessions in the UK

Bootlin 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 Bootlin, and is available under the same license. Feel free to reuse it and improve it as long as you keep the original author!

Bootlin New Year – 2014

A French version also exists.

The Bootlin team wishes you a Happy New Year for 2014, with plenty of optimism and energy!

We are taking this opportunity to give some news about Bootlin.

In 2013, Bootlin significantly increased its contribution to open-source projects, especially at the Linux kernel level.

639 patches integrated in the Linux kernel, mainly to improve support for Marvell ARM processors and Allwinner ARM processors. For all kernel releases published in 2013, Bootlin has been in the top 30 contributing companies. We now have a significant experience in integrating support for ARM processors in the Linux kernel, and we expect to work more in this area in 2014.

595 patches integrated in the Buildroot embedded Linux build system, in a large number of areas, making Bootlin the second most important contributor after Buildroot’s maintainer. This effort allows Bootlin to keep an up-to-date expertise in cross-compilation and build systems.

26 patches integrated in the Barebox bootloader:

22 patches to the Yocto Freescale layer, mainly adding support for the Crystalfontz boards. In the process, a new image type was developed and significant improvements were made to the Barebox recipe.

Several of these contributions, and many other activities, were driven by development and consulting activities in 2013, with mainly:

  • Linux kernel code development, adding and maintaining support for customer ARM processors or boards in the mainline Linux kernel. Especially on Marvell and Freescale processors.
  • Linux kernel, driver development and build system integration for an Atmel SAMA5 based medical device.
  • Development of Linux kernel drivers for radio-frequency transceivers, on an Atmel SAMA5 based home automation platform.
  • Boot time optimization audits.
  • Buildroot consulting and audit.

We have also significantly improved and updated our training courses:

  • Our embedded Linux and kernel driver development course was updated to use the BeagleBone Black platform, to cover the usage of the Device Tree on ARM platform, and to use a fun I2C device to illustrate the development of a device driver in our labs.
  • Our Android system development course was updated to use Android 4.x, and use the BeagleBone Black as the development platform for the practical labs.
  • Our embedded Linux system development course was updated to use more recent versions of the Linux kernel, in order to cover the usage of the Device Tree on ARM platforms.

Our training materials remain freely available under a Creative Commons license, including their source code, available from a public Git repository.

Bootlin continues to believe that participating to conferences is critical to keep its engineers up to date with the latest Linux developments and create connections with the developers of the Linux community which are essential to make our projects progress faster. For this purpose, we participated to a large number of conferences in 2013:

  • FOSDEM 2013, in Brussels, Belgium. Our CTO and engineer Thomas Petazzoni gave a talk about ARM kernel development
  • Buildroot Developers Meeting, Brussels, Belgium. Our engineer Thomas Petazzoni organized and participated to this 2-days meeting, sponsored by Google, to work on Buildroot developments.
  • Embedded Linux Conference 2013 and Android Builders Summit 2013, in San Francisco, United States. Our engineer Gregory Clement gave a talk about the Linux kernel clock framework. Our engineer Thomas Petazzoni gave a talk about ARM kernel development. See also our videos.
  • Linaro Connect Europe 2013, Dublin Ireland. Our engineer Thomas Petazzoni participated to numerous discussions related to support for ARM processors in the Linux kernel.
  • Linux Plumbers 2013, New Orleans, United States. Our engineer Maxime Ripard attended the conference, and participated to discussions around Android and Linux kernel development.
  • Kernel Recipes, Paris, France. Both Bootlin CEO Michael Opdenacker and CTO Thomas Petazzoni participated to this Linux kernel conference, and Thomas gave two talks: one about ARM kernel development and one about Buildroot.
  • ARM kernel mini-summit 2013, Edinburgh, UK. Our engineers Gregory Clement, Thomas Petazzoni and Maxime Ripard participated to the invitation-only ARM kernel mini-summit. This summit is the key place to discuss and define the next directions for support for ARM processors in the Linux kernel.
  • Embedded Linux Conference Europe, Edinburgh, UK. Gregory Clement gave a talk about about the Linux kernel clock framework and Thomas Petazzoni gave a talk about the Device Tree.
  • Buildroot Developers Meeting, Edinburgh, UK. Our engineer Thomas Petazzoni organized and participated to this 2-days meeting, sponsored by Imagination Technologies, to work on Buildroot development.

A very important development of Bootlin in 2013 is the addition of a new engineer to our team: Alexandre Belloni joined us in March 2013. Alexandre has a very significant embedded Linux and kernel experience, see his profile.

Now, let’s talk about our plans for 2014:

  • Hire several additional engineers. One of them has already been hired and will join us in April, bringing a significant Linux kernel development experience, including mainline contribution.
  • Our involvement in support for ARM processors in the Linux kernel will grow significantly.
  • Two new training courses will be released: one “Boot time reduction” training course, and an “OpenEmbedded and Yocto” training course.
  • For the first time, we will organize public training sessions (open to individual registration) outside of France.
    • Our next Android system development session in English will happen on April 14-17 in Southampton, UK
    • We are also working on embedded Linux and Kernel and driver development sessions in the USA, to be announced in the next weeks.
    • We also plan to organize embedded Linux and Kernel and driver development sessions in Germany, with German speaking trainers.
    • By the way, our Android system development courses in French will continue to run in Toulouse, but there will also be a session on April 1-4 in Lyon.

    See also the full list of public sessions.

As in 2013, we will participate to several key conferences. We have already planned our participation to: Linux Conf Australia (January 2014), FOSDEM (February 2014), Embedded Linux Conference (April 2014) and the Embedded Linux Conference Europe (October 2014).

You can follow Bootlin news by reading our blog and by following our quick news on Twitter. We now have a Google+ page too.

Again, Happy New Year!

The Bootlin team.

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.

Bootlin at Linux Conf Australia, January 2014

Linux Conf Augstralia 2014Linux Conf Australia is by far the most well-known Linux related conference of the southern hemisphere, with a good number of Linux kernel related talks and discussions, as well as many other topics around the Linux ecosystem. The 2014 edition of the event will take place in Perth, Australia, and the schedule of talks and mini-confs looks very promising!

For the first time, Bootlin will be participating to this conference: our CTO and embedded Linux engineer Thomas Petazzoni will be giving a talk titled Buildroot: building embedded Linux systems made easy!, during which he will be presenting what Buildroot is, what it is useful for, and how it works.

Beyond this talk, Thomas will be attending the full week of conferences, so do not hesitate to get in touch with him, especially if you’re interested in embedded Linux topics, Buildroot, ARM kernel development, and in Bootlin!

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 Bootlin 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.

Linux init failures now easier to debug

If you are an embedded Linux developer too, you have probably been frustrated by the lack of information from the Linux kernel when it failed to start the init process when you’re building a new root filesystem. The only thing you get is No init found, and this could hide many different causes:

  • No init program candidate found at all
  • Some init program candidates exist but they can’t be executed, for multiple possible causes (missing execute permissions, failed to load shared libraries, executable compiled for an unknown architecture…)

The good news is that this source of frustration will be gone in Linux 3.13. Thanks to a Bootlin commit merged on Nov. 13, 2013, whenever an attempt to execute an init program candidate fails, there is a message in the console detailing the executable path and the error code. For example:

Starting init: /sbin/init exists but couldn't execute it (error -13)

When you get such a message, all you have to do is lookup the error code in include/uapi/asm-generic/errno-base.h or maybe in uapi/asm-generic/errno.h. In the above example, the -13 code meant permission denied, typically because of missing execution rights.

This had been annoying me for a long time, and I am glad that the Linux kernel community accepted my improvement!

By the way, many more improvements to the Linux kernel from Bootlin are currently getting merged in 3.13. See all our contributions to the Linux kernel.