Buildroot 2015.05 release, Bootlin contributions inside

Buildroot LogoThe Buildroot project has recently released a new version, 2015.05. With exactly 1800 patches, it’s the largest release cycle ever, with patches from more than 100 different contributors. It’s an impressive number, showing the growing popularity of Buildroot as an embedded Linux build system.

The CHANGES file summarizes the most important improvements of this release.

Amongst those 1800 patches, 143 patches were contributed by Bootlin. Our most significant contributions for this release have been:

  • Addition of a package for the wf111 WiFi drivers. They allow to use a WiFi chip from Bluegiga, which is being used in one of our customer projects.
  • Addition of the support for using uClibc-ng. uClibc-ng is a “collaborative” fork of the uClibc project, which aims at doing more regular releases and have better testing. Maintained by Waldemar Brodkorb, the project has already seen several releases since its initial 1.0 release. Waldemar is merging patches from the original uClibc regularly, and adding more fixes. It allows Buildroot and other uClibc users to have well-identified uClibc stable versions instead of a 3 years old 0.9.33.2 version with dozens of patches on top of it. uClibc-ng is not currently used as the default uClibc version as of 2015.05, but it might very well be the case in 2015.08.
  • Important internal changes to the core infrastructure. Until this release, the make legal-info, make source, make external-deps and make source-check logic was relying only on the Buildroot configuration file. This was giving correct results for target packages which all have a corresponding Buildroot configuration option, but not for host packages (which for most of them don’t have Buildroot configuration options). Only a manual two-level dependency handling was done for the host packages for the above mentioned commands. With our work, the handling of those features has been moved to be part of the package infrastructure itself, so it’s using proper make recursivity to resolve the entire dependency tree. Due to this, the results of make legal-info or make external-deps may be longer following this release, but it’s because it’s now actually correct and complete. You can look at the patches for more details, but these changes are very deep into the core Buildroot infrastructure.
  • Large number of build fixes. We contributed 52 patches fixing issues detected by the autobuild infrastructure.
  • Addition of the imx-usb-loader package, which can be used to load over USB a new bootloader on i.MX6 platforms, even if the platform has no bootloader or a broken bootloader. We also use it as part of one of our customer projects.

With 142 patches, Bootlin engineer Thomas Petazzoni is the third contributor to this release by number of patches:

git shortlog -s -n 2015.02..

   397	Bernd Kuhls
   393	Gustavo Zacarias
   142	Thomas Petazzoni

But by far, our most important contribution by far for this release is Thomas acting as the interim maintainer: on the total of 1800 patches merged for this release, Thomas has been the committer of 1446 patches. He has therefore been very active in merging the patches contributed by the Buildroot community.

There are already some very interesting goals set for the Buildroot 2015.08 release, as you can see on the Buildroot release goals page.

Also, if you want to learn Buildroot in details, do not hesitate to look at our Buildroot training course!

New training course on Buildroot: materials freely available

Buildroot LogoLast year, Bootlin launched a new training course on using the Yocto Project and OpenEmbedded to develop embedded Linux systems. In the selection of build system tools available in the embedded Linux ecosystem, another very popular choice is Buildroot, and we are happy to announce today that we are releasing a new 3 days training course on Buildroot!

Bootlin is a major contributor to the Buildroot upstream project, with more than 2800 patches merged as of May 2015 (including the ones contributed with our previous name). Our engineer Thomas Petazzoni alone has contributed more than 2700 patches. He has gathered an extensive knowledge of Buildroot and its internals, being one of the primary authors of the core infrastructures of Buildroot. He is a major participant to the Buildroot community, organizing the regular Buildroot Developer Days, supporting users through the mailing list and on IRC. Last but not least, Thomas acts as an interim maintainer when the main Buildroot maintainer is not available, an indication of Thomas strong involvement in the Buildroot project.

In addition, Bootlin has used and is using Buildroot in a significant number of customer projects, giving us an excellent view of Buildroot usage for real projects. This feedback has been driving some of our Buildroot contributions over the last years.

The 3 days training we have developed covers all the aspects of Buildroot: basic usage and configuration, understanding the source and build trees, creating new packages including advanced aspects, analyzing the build, tips for organizing your Buildroot work, using Buildroot for application development and more. See the detailed agenda.

buildroot-slidesWe can deliver this training course anywhere in the world, at your location (see our rates and related details). We have also scheduled a first public session in English in Toulouse, France, on November 30 to December 2. Contact us at training@bootlin.com if you are interested.

And finally, last but not least, like we do for all our training sessions, we are making the training materials freely available under a Creative Commons BY-SA license, at the time of the training announcement: the first session of this course is being given this week. For the Buildroot training, the available materials are:

Our materials have already been reviewed by some of the most prominent contributors to Buildroot: Peter Korsgaard (Buildroot maintainer), Yann E. Morin, Thomas De Schampheleire, Gustavo Zacarias and Arnout Vandecappelle. We would like to take this opportunity to thank them for their useful comments and suggestions in the development of this new training course.

Bootlin at FOSDEM 2015

FOSDEM BannerFor many open-source developers based in Europe, the FOSDEM is probably the most useful, interesting and exciting conference. Once again this year, several Bootlin engineers will attend the conference:

  • Maxime Ripard, mainly involved in Allwinner related kernel development, as well as more recently OpenWRT support for Marvell platforms
  • Antoine Ténart, involved in Marvell Berlin related kernel development, and one of the developers of our Yocto Project and OpenEmbedded training course
  • Alexandre Belloni, involved in Atmel processors related kernel development, and also one of our Yocto expert.
  • Thomas Petazzoni, involved in Marvell EBU processors related kernel development, and doing a lot of Buildroot contributions.

If you are attending, and want to know more about Bootlin, or discuss career or project opportunities, do not hesitate to contact us prior to the conference. Many of us will probably attend a significant number of talks from the Embedded track, so it should be easy to find us.

Last but not least, Alexandre Belloni will be giving a talk about Starting with the Yocto Project, which will take place on Sunday, at 3 PM in room Lameere.

Finally, Thomas Petazzoni has organized and will participate to the Buildroot Developers Meeting organized right after FOSDEM, and sponsored by Google and Mind.

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.

2014 Q2 newsletter

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

Embedded Linux Conference 2014, Bootlin participation

San JoséOne of the most important conference of the Embedded Linux community will take place at the end of this month in California: the Embedded Linux Conference will be held in San Jose from April, 29th to May, 1st, co-located with the Android Builders Summit. The schedule for both of these events has been published, and it is full of interesting talks on a wide range of embedded topics.

As usual, Bootlin will participate to this conference, but this participation will be the most important ever:

If you are interested in embedded Linux, we highly advise you to attend this conference. And if you are interested in business or recruiting opportunities with Bootlin, it will also be the perfect time to meet us!

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 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.

Increasing activity in the Buildroot community

In the recent times, the Buildroot project has seen a particular high level of activity, with a significant number of new contributors and contributions. It is an interesting opportunity to have a look at some statistics of the project activity in the last years: they show that the Buildroot project is really active, and in rapid development.

First, a look at the number of commits per month is an obvious way of looking at the activity of an open-source project. For two years, the project has seen each month at least 150 commits, and since for the last year, most of the months have seen between 300 and 400 commits.

Buildroot activity in commits

Another interesting data point is that this increasing number of commits is not only due to an increasing effort from the existing core developers, but rather due to an increasing number of contributors. The following graph, which displays the number of unique contributors having had patches merged each month, clearly shows that the Buildroot community is growing. From an average of 10-15 contributors per month a few years back, the project is now having between 30 and 40 unique contributors each month.

Number of Buildroot contributors

The mailing list activity also nicely reflects this increasing activity: it is now receiving almost each month between 1500 and 2000 e-mails, which means between 50 and 65 e-mails per day, and it starts to be difficult to read everything!

Number of Buildroot mailing list posts

Finally, the number of packages has also increased progressively over the last two years. As can be seen on the graph below, the period 2008 → 2011 hasn’t seen a big increase in the number of packages, as it was a period mainly focused on refactoring and cleanup work. After this cleanup work, it seems that Buildroot has started gaining in popularity, and more work was done to add more packages for various useful open-source components in embedded systems. Since 2011, the number of packages has been growing regularly, starting from less than 700 in 2011 to reach almost 1200 packages today.

Number of Buildroot packages

All in all, those four graphs clearly show a nice increase of activity within the Buildroot project, which is really cool!

Some notes on how the data was computed:

  • The number of commits per month was obtained by doing a git log --pretty=online --since=yyyy-mm-dd --until=yyyy-mm-dd | wc -l for each month.
  • The number of contributors was obtained by doing a git shortlog -sn --since=yyyy-mm-dd --until=yyyy-mm-dd | wc -l for each month.
  • The e-mail statistics were obtained by looking at the number of messages displayed in the HTML archives, per month, as in http://lists.busybox.net/pipermail/buildroot/2013-August/thread.html.
  • The number of packages was computed using an approximate method, that consists in counting the number of .mk files in Buildroot (a few .mk files are not packages, but the vast majority of them are). The exact command used was git checkout -q $(git rev-list -n 1 --before=2013-08-01 master) && find . -name '*.mk' | wc -l.

Bootlin at the ARM Kernel Summit, the Embedded Linux Conference and the Buildroot Developers Meeting

Late october will be a busy moment for all the embedded Linux developers meeting in Edinburgh, UK. The Linux Foundation is organizing a number of conferences here, including the Embedded Linux Conference Europe (October 24-25) and LinuxCon Europe (October 21-23), and many co-located other events.

Bootlin will be present at several of these events:

  • First, three Bootlin engineers will be present at the ARM kernel summit on October 22nd and 23rd. The ARM kernel summit is an invitation-only conference, organized in relation with the Linux Kernel Summit. Gregory Clement, Maxime Ripard and Thomas Petazzoni, engineers at Bootlin have been invited due to their participation to the ARM support in the kernel, mainly on Allwinner SOCs for Maxime and on Marvell SOCs for Gregory and Thomas. Being present at this event is an excellent opportunity to be part of the discussion that shapes the future of ARM support in Linux, and strengthen our relations with other members of this growing community.
  • Then, the entire technical team of Bootlin will attend the Embedded Linux Conference, on October 24th and 25th. Several talks will also be given by Bootlin engineers:
    • On Thursday, 24th October at 11:40 AM, Thomas Petazzoni will give a talk titled Device Tree for dummies!, which will give an introduction to the Device Tree on ARM: what it is, how it is compiled, how it used by the kernel, how Device Tree bindings are defined, how drivers are affected by the Device Tree, etc.
    • At the same time in another room, Michael Opdenacker will lead a Bird of a Feather session dedicated to Small Businesses in the embedded Linux world. Exchanging experiences, networking with other companies working in the same field, etc.
    • Still on Thursday, at 3 PM, Gregory Clement will give a talk on the Linux kernel Common Clock Framework, which will be an updated version of the talk he gave at ELC earlier this year.
    • On Friday, 25th October at 9:30 AM, Thomas Petazzoni will be part of the keynote panel session dedicated to a discussion on Embedded Linux build systems together with Tim Bird (Sony Mobile), Ross Burton (Intel), and Karim Yaghmour (Opersys), the panel being moderated by Jeff Osier-Mixon (Intel).
  • On Saturday 26th and Sunday 27th October, the Buildroot community is organizing its traditional Developers Meeting, to which Thomas Petazzoni will participate. Some of the core Buildroot developers will join for two days of discussion and work to improve this embedded Linux build system.

As you can see, this will be a very interesting and busy week, and we’re all looking forward to meeting more embedded Linux developers and learning about the latest technologies in this field.