2015 Q1 newsletter

The Bootlin team wishes you a Happy New Year for 2015, with plenty of optimism and energy!

Bootlin is happy to take this opportunity to share some news about the latest training and contribution activities of the company.

Kernel contributions

We continue to work significantly on support for various ARM processors in the Linux kernel. Our contributions to the latest kernel releases:

  • 147 patches from Bootlin merged in Linux 3.17, making Bootlin the 14th contributing company for this release by number of patches. See our blog post about this release.
  • 155 patches from Bootlin merged in Linux 3.18, making Bootlin the 14th contributing company. See our blog post for more details.
  • For the upcoming 3.19 release, we already have 196 patches merged.

One of the highlights was that we added support for the Atmel SAMA5D4 SoC to the Linux kernel even before the new chip was announced by Atmel! That’s a very positive sign for customers when an SoC is supported in the mainline Linux kernel sources right at product launch, instead of having to wait for months or years before the community developers can catch up.

Note that we also added Atmel SAMA5D3 SoC support to Xenomai, a hard real-time extension for the Linux kernel. Thanks to this, the Atmel SAMA5D3 Xplained board can now run with the 2.6.x release of Xenomai.

Besides those highlights, most of our kernel contributions were as usual centered around support for specific families of ARM processors: CPUs from Marvell EBU and Marvell Berlin, from Atmel and from Allwinner. We added a new network driver for some Marvell EBU processors, added SMP support for Marvell Berlin processors, added a DMA controller driver for Allwinner processors, and did a lot of maintenance work to support these processors in the mainline kernel.

Buildroot contributions

Our involvement into the Buildroot project, a popular embedded Linux build system, is going on. Our engineer Thomas Petazzoni contributed 136 patches to the 2014.11 release, making him the second contributor by number of patches. Thomas is also taking care of the maintenance of the project on a more regular basis, reviewing and merging patches from contributors.

OpenWRT contributions

We have recently started contributing to the OpenWRT project: improve the kernel support to use defconfig, introduce a notion of board to support different NAND configurations for each platform. We will soon to be pushing support for the Marvell Armada 385 platform, and improved support for the Marvell Armada 370 and XP platforms.

Recent projects

Besides our publicly visible kernel contributions, we do also work on customer-specific projects. Among the latest projects we have done:

  • Develop a complete Board Support Package for a custom TI AM335x based platform: U-Boot porting, Linux kernel porting, and development of a Yocto-generated system. Qt5 and OpenGL are used for the graphical application, a fairly complex audio setup had to be supported, and many traditional interfaces as well (USB Host and Device, CAN, display, etc.)
  • Develop a Board Support Package for a custom Marvell Armada 375 based platform for a telephony system. Not only did we port a Linux kernel on this platform, but we also wrote several DAHDI drivers to interface the telephony hardware of the platform with Asterisk.
  • NAND and UBI stress-testing for a customer-specific Freescale i.MX28 based platform. We improved the NAND controller driver, added a new MTD tool to generate bitflips, and did some long term power-cut stress-testing of the UBIFS setup to ensure the reliability of the platform. See our kernel driver improvements and the new nandflipbits tool.
  • Adapt an existing ADC driver for a customer-specific platform to the modern Industrial Input Output (IIO) subsystem of the kernel.

Conferences: FOSDEM, Embedded World and Embedded Linux Conference

Several Bootlin engineers will participate to the FOSDEM conference, taking place on January 30 and February 1 in Brussels. In addition, Thomas Petazzoni will be participating to the Buildroot Developers Meeting that takes place right after FOSDEM in the Google offices in Brussels.

Bootlin will participate to the Embedded World trade show on February 24-26 in Nuremberg, Germany. We will be present at Atmel’s booth and visiting exhibitor booths too. For people in Europe, this will be a good opportunity to ask your questions about our embedded Linux training and engineering services. In particular, you will be able meet our engineers Alexandre Belloni, Thomas Petazzoni (CTO), Michael Opdenacker (CEO) and Anja Roubin as well, the new person in charge of our training services.

This year again, most of the Bootlin engineering team (7 engineers) will participate to the 2015 edition of the Embedded Linux Conference on March 23-25 in San Jose, California. We submitted several talk proposals, but our presence won’t depend on the number of talks that are eventually accepted. Participating to this conference, and to its European edition in the fall too, is very important for us to make sure we do not miss any of the interesting developments in the technical community, and above all to strengthen our ties with the community developers. This helps us to be good technical trainers with valuable experience and information to share. The strong relationships with other community developers (and in particular with project maintainers) also help us when our customers contract us to add hardware support or features to official versions of community projects such as the Linux kernel.

Free technical documentation resources

Since the latest edition of this newsletter, we started running our new Yocto Project and OpenEmbedded course, and we released all training materials for this course. As usual, such materials are meant to be used by people learning by themselves too. All you have to do is get your hands on a Beaglebone Black board, read the slides and try to do the labs!

Our engineer Maxime Ripard also contributed documentation about the DMAEngine subsystem in the Linux kernel.

Upcoming training sessions – Now in Paris too!

The news is that we will run new public sessions in Paris, in addition to the ones we usually organize in Toulouse, Avignon and Lyon in France. We are starting with our embedded Linux and our Yocto courses, but other topics will follow too.

So, here are our next session dates:

See sessions and dates for more details. Of course, we can also deliver our training courses at your location, anywhere in the world. Feel free to contact us for a quote.

If you are interested in more frequent news about Bootlin, you can follow us on Twitter, Google+ and LinkedIn.

Yocto Project and OpenEmbedded training materials published

Yocto Project and OpenEmbedded trainingAs we announced in out latest newsletter, we recently launched a new Yocto Project and OpenEmbedded development training course.

The first public session will take place in Toulouse, France on November 18-20 and we still have a few seats available. We can also deliver on-site sessions at the location of your choice, see our Training cost and registration page for more details.

However, what brings us here today is that we are happy to announce the release of all the training materials of this new course: like all Bootlin training materials, they are available under the Creative Commons Attribution Share-Alike license.

Fully committed to its knowledge sharing principles, Bootlin has chosen to publish those materials even before the first session has taken place.

The materials available are:

We of course welcome reviews, feedback and comments about these materials, in order to improve them where needed. Send us your comments!

Bootlin registered as Yocto Project Participant.

Yocto_Project_Badge_Participant_Web_RGB
Earlier this month, Bootlin applied and was elected Yocto Project Participant by the Yocto Project Advisory Board. This badge is awarded to people and companies actively participating to the Yocto Project and promoting it.

We have mainly contributed to the meta-fsl-arm and meta-fsl-arm-extra layers but we also have some contributions in OpenEmbedded Core and in the meta-ti layer.

Bootlin offers a Yocto Project and OpenEmbedded training course that we can deliver at your location, or that you can attend by joining one of our public sessions. Our engineers are also available to provide consulting and development services around the Yocto Project, to help you use this tool for your embedded Linux projects. Do not hesitate to contact us!

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 Bootlin 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 training@bootlin.com 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.

Embedded Linux course in Madrid – July 7-11

We are happy to announce a new Embedded Linux training course on July 7-11, in Madrid, Spain.

IGEPv2 boardIt is organized by our partners ISEE (the makers of the IGEPv2 board that we are using in this course), and Silica, a well known component is distributor who is welcoming the session in its offices in Madrid.

The course will be instructed in English by our trainer Marcin Bis. Marcin Bis

The registrations are directly handled by ISEE. See details.

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!

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 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.

Announcing our “Android System Development” training

Android RobotFor multiple years, Bootlin 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.