Bootlin – Page 53 – Embedded Linux and kernel engineering

Embedded Linux Conference Europe 2011 videos

One week after the end of the Embedded Linux Conference Europe 2011, we are pleased to release the videos of all talks that took place during this event. We would like to thank the Linux Foundation for allowing us to record those talks and to share freely the resulting videos on-line, and also thank the Clarion Congress Hotel technical staff for helping us with technical details related to video recording.

Below, you’ll find 51 videos, in both a 1920×1080 HD format and a reduced 800×450 format. In total, it represents 28 GB of video, for a duration of 2214 minutes, that is more of 36 hours of video. We hope that you will enjoy those videos and that these will be useful to those who couldn’t attend the conference.

Jim Zemlin
Executive Director of The Linux Foundation
Imagine a World Without Linux
Video (24 minutes):
full HD (220M), 450×800 (76M)

Linus Torvalds, Alan Cox, Thomas Gleixner, Paul McKenney
moderated by Lennart Poettering
Kernel Developer Panel
Video (55 minutes):
full HD (622M), 450×800 (191M)

Zach Pfeffer
Linaro
Linaro’s Android Platform
Video (45 minutes):
full HD (604M), 450×800 (164M)

Thomas Gleixner
Linutronix
State of PREEMPT_RT
Video (46 minutes):
full HD (374M), 450×800 (147M)

Jessica Zhang
Intel
The Yocto Project Eclipse plug-in: An effective IDE environment for both Embedded Application and System developers
Video (45 minutes):
full HD (431M), 450×800 (118M)

Satoru Ueda
Sony Corporation / Japan OSS Promotion Forum
Contributing to the Community? Does your Manager Support You?
Video (42 minutes):
full HD (556M), 450×800 (140M)

Benjamin Zores
Alcatel-Lucent
Embedded Linux Optimization Techniques: How Not To Be Slow
Slides
Video (44 minutes):
full HD (328M), 450×800 (125M)

Ohad Ben-Cohen
Texas Instruments
Remote Processor Messaging
Slides
Video (48 minutes):
full HD (433M), 450×800 (131M)

Jeff Osier-Mixon
Intel
Collaborative Initiatives in Embedded Linux
Video (26 minutes):
full HD (266M), 450×800 (73M)

Karim Yaghmour
Opersys Inc.
Leveraging Android’s Linux Heritage
Video (51 minutes):
full HD (419M), 450×800 (168M)

Pierre Tardy
Intel
Using pytimechart For Real World Analysis
Slides
Video (51 minutes):
full HD (495M), 450×800 (132M)

Arnd Bergmann
Linaro
Optimizations for Cheap Flash Media
Video (44 minutes):
full HD (524M), 450×800 (146M)

Vitaly Wool
Sony Ericsson
Saving Power with Wi-Fi: How to Prolong Your Battery Life and Still Stay Connected
Slides
Video (50 minutes):
full HD (371M), 450×800 (143M)

David Stewart
Intel
Developing Embedded Linux Devices Using the Yocto Project and What’s new in 1.1
Slides
Video (47 minutes):
full HD (370M), 450×800 (124M)

Tetsuyuki Kobayashi
Kyoto Micro Computer
Android is NOT Just “Java on Linux”
Slides
Video (37 minutes):
full HD (542M), 450×800 (129M)

Thomas Petazzoni
Bootlin
Using Buildroot For a Real Project
Slides
Video (55 minutes):
full HD (408M), 450×800 (156M)

Tim Bird
Sony Network Entertainment
Status of Embedded Linux BoFs
Slides
Video (60 minutes):
full HD (877M), 450×800 (213M)

Lauro Ramos Venancio and Samuel Ortiz
Instituto Nokia de Tecnologia, Intel
The Linux NFC Subsystem
Slides
Video (31 minutes):
full HD (229M), 450×800 (87M)

David Anders
Texas Instruments
Board Bringup: LCD and Display Interfaces
Slides
Video (39 minutes):
full HD (242M), 450×800 (98M)

Antti Aumo
President of Global Solutions at Ixonos
Re-Defining the Cloud Phone
Video (32 minutes):
full HD (360M), 450×800 (108M)

Dirk Hohndel
Chief Linux and Open Source Technologist at Intel
Reflection on 20 Years of Linux
Video (30 minutes):
full HD (235M), 450×800 (92M)

Grant Likely
Secret Lab
Device Tree Status Report
Video (51 minutes):
full HD (775M), 450×800 (178M)

Laurent Pinchart
Ideas on Board
Success Story of the Open-Source Camera Stack: The Nokia N9 Case
Slides
Video (48 minutes):
full HD (308M), 450×800 (120M)

Avinash Mahadeva and Vishwanth Sripathy
Texas Instuments
SOC Power Management – Debugging and Optimization Techniques
Video (41 minutes):
full HD (288M), 450×800 (108M)

Rafael J. Wysocki
Faculty of Physics, U. Warsaw / SUSE Labs
Power Management Using PM Domains on SH7372
Slides
Video (46 minutes):
full HD (692M), 450×800 (157M)

Sascha Hauer
Pengutronix e.K.
A Generic Clock Framework in the Kernel: Why We Need It and Why We Still Don’t Have It
Video (45 minutes):
full HD (345M), 450×800 (134M)

Ruud Derwig
Synopsys
Android Platform Optimizations
Slides
Video (43 minutes):
full HD (266M), 450×800 (105M)

Inki Dae
Samsung Electronics
DRM Driver Development For Embedded Systems
Slides
Video (22 minutes):
full HD (367M), 450×800 (91M)

Lorenzo Pieralisi
ARM Ltd.
Consolidating Linux Power Management on ARM Multiprocessor Systems
Slides
Video (46 minutes):
full HD (283M), 450×800 (113M)

Thomas Petazzoni
Bootlin
Using Qt For Non-Graphical Applications
Slides
Video (49 minutes):
full HD (340M), 450×800 (124M)

Marek Szyprowski and Kyungmin Park
Samsung Electronics
ARM DMA-Mapping Framework Redesign and IOMMU Integration
Slides
Video (49 minutes):
full HD (790M), 450×800 (195M)

Keerthyd Jagadeesh and Vishwanath Sripathy
Texas Instruments
Thermal Framework for ARM based SOCs
Video (42 minutes):
full HD (316M), 450×800 (113M)

Marc Titinger
ST Microelectronics
Efficient JTAG-Based Linux Kernel Debugging
Slides
Video (57 minutes):
full HD (382M), 450×800 (141M)

Tsugikazu Shibata
NEC and Linux Foundation Board Member
Toward the Long Term Stable Kernel tree for The Embedded Industry
Video (32 minutes):
full HD (606M), 450×800 (145M)

Lisko Lappalainen
MontaVista Software
Secure Virtualization in Automotive
Video (40 minutes):
full HD (301M), 450×800 (116M)

Jeff Osier-Mixon
Intel
Yocto Project Community BoFs
Video (60 minutes):
full HD (451M), 450×800 (167M)

Jon Corbet
Editor at LWN.net
The Kernel Report: 20th Anniversary Edition
Video (28 minutes):
full HD (218M), 450×800 (88M)

Wim Coekaerts
Senior Vice President, Linux and Virtualization Engineering at Oracle
Engineered Systems With Linux
Video (21 minutes):
full HD (175M), 450×800 (68M)

Andrea Gallo
ST-Ericsson
ARM Linux Kernel Alignment and Benefits For Snowball
Slides
Video (47 minutes):
full HD (394M), 450×800 (133M)

Liam Girdwood and Peter Ujfalusi
Texas Instruments
Smart Audio: Next-Generation ASoC For Smart Phones
Video (50 minutes):
full HD (367M), 450×800 (124M)

Pawel Moll
ARM Ltd.
Linux on Non-Existing SoCs
Video (52 minutes):
full HD (483M), 450×800 (143M)

Koen Kooi
The Angstrom Distribution
Integrating systemd: Booting Userspace in Less Than 1 Second
Slides
Video (44 minutes):
full HD (343M), 450×800 (125M)

Sylvain Leroy and Philippe Thierry
Grsecurity in Embedded Linux Used in Android Operating System
Slides
Video (40 minutes):
full HD (384M), 450×800 (110M)

MyungJoo Ham
Samsung Electronics
Charger Manager: Aggregating Chargers, Fuel-Gauges and Batteries
Slides
Video (33 minutes):
full HD (434M), 450×800 (109M)

Arnd Bergmann
Linaro
News From the ARM Architecture
Video (49 minutes):
full HD (421M), 450×800 (150M)

Frank Rowand
Sony Network Entertainment
How Linux PREEMPT_RT Works
Slides
Video (45 minutes):
full HD (378M), 450×800 (135M)

Catalin Marinas
ARM Ltd.
Linux Support for the ARM Large Physical Address Extensions
Slides
Video (52 minutes):
full HD (594M), 450×800 (170M)

Jim Huang
0xlab
Build Community Android Distribution and Ensure the Quality
Video (44 minutes):
full HD (472M), 450×800 (143M)

Till Jaeger
JBB Rechtsanwälte
The Case AVM v. Cybits: The GPL and Embedded Systems
Video (42 minutes):
full HD (362M), 450×800 (124M)

Darren Hart
Intel
Tuning Linux For Embedded Systems: When Less is More
Slides
Video (45 minutes):
full HD (482M), 450×800 (135M)

Wolfram Sang
Pengutronix e.K.
Developer’s Diary: It’s About Time
Video (49 minutes):
full HD (482M), 450×800 (141M)

Report from the Buildroot Developer Day

Right after the Embedded Linux Conference Europe, a new edition of the Buildroot Developer Day took place on Saturday, 29th October 2011 in Prague.

Unlike past Buildroot Developer Day that were followed only by Buildroot developers and Yann E. Morin as the crosstool-NG maintainer, this edition of the Buildroot Developer Day was followed by developers of other build systems: Robert Schwebel from PTXdist, Esben Haabendal from OE-lite and we also had the opportunity to discuss with Benjamin Zores and Davide Calvalca from OpenBricks. This made the day very interesting, even though if it was a bit less focused on Buildroot than expected.

I have written and sent a complete report of the discussions, which were about the following topics:

Expanding the send-patches.org initiative. This was an important topic, as developers of several build systems had the opportunity to discuss it during this meeting.
The testing infrastructure of Buildroot, how to improve it.
Package management. A long requested feature for Buildroot, but which would make Buildroot a lot more complicated and probably less reliable. Following this meeting, our position is to not implement such a feature and to keep Buildroot simple. Should package management be necessary, there are other build systems that implement such a feature (at the expense of higher complexity, of course).
Toolchain backend. We will soon switch to using the crosstool-NG backend as the default method of building toolchains in Buildroot. Long term, we would like to get rid of the code that builds a toolchain in Buildroot in order to factorize the efforts at the level of the crosstool-NG project.
Migration of the documentation to the asciidoc format has been accepted, and the next version of Buildroot will feature this updated documentation.
Out-of-tree build of packages. This is a very internal question to how Buildroot builds package. See the report for details.
Website improvement, because the current Buildroot website is quite ugly.
Maintenance process. We are seeing a quite significant increase in the number of contributions to Buildroot and some of these contributions are taking more and more time to get integrated. We discussed the topic and came up with a few proposals on how to improve the situation.
Host packages visible in menuconfig. Traditionally, packages built for the host are not user-selectable as Buildroot since they are just dependencies to build target packages. However, we had the case of some host packages that should be user-selectable. The principle has been agreed upon.
Per-package device file handling. A mechanism proposed by Maxime Ripard, from Bootlin, to allow each package to specify special permissions/owernships/device files to install in the target filesystem.
Relocatable toolchain and SDK. Buildroot produces a SDK (set of utilities and libraries to build applications for the target independently from Buildroot), but this SDK is currently not relocatable. We discussed the various issues to fix to make it relocatable.
Licensing report generation, which is also a feature that has been requested in the past.

All in all, it was a very interesting and motivating day, that got closed by a short visit of Prague’s center and a nice dinner. The next edition of the Buildroot Developer day will take place on Friday, 3rd 2012 in Brussels, the day before the FOSDEM conference. It is open to all Buildroot users and developers!

Regarding Buildroot itself, the maintainer Peter Korsgaard will release 2011.11-rc1 early next week, and 2011.11 by the end of November. This release will have several new useful features, which we will cover in details in a future blog post.

Back from Embedded Linux Conference Europe 2011

As we announced in a previous blog post, a large part of the Bootlin team attended the 2011 edition of the Embedded Linux Conference Europe in Prague last week.

This was the first european edition of the conference to last three days, and this was much appreciated as it gave the opportunity to attend a lot more conferences and to spend more time talking with developers of the community. My colleagues Michael Opdenacker and Maxime Ripard as well as myself really enjoyed this conference. It really allows to connect with members of the community, learn a lot of new things, and bring home a huge motivation to work on various projects. Despite a few marketing-oriented keynotes, the conference has kept its highly-technical profile, which is great.

We have recorded all the talks of the three tracks of the Embedded Linux Conference Europe (unfortunately, there wasn’t a similar video crew for the LinuxCon Europe conference which was taking place at the same time). Many of those videos should have a much higher audio quality than what we had in the past, since we could capture the audio directly for the conference room sound system. Unfortunately, one of our camcorders generates a loud noise when connected both to the audio system of the conference room and to the power adapter (this noise disappears when the camcorder is on battery). Therefore, not all conferences could be recorded with this improved audio quality. The encoding and upload of those videos has started on Sunday evening, just a few hours after landing in Toulouse when coming back from ELCE. The process is running 24/24 on two machines in parallel, and we therefore hope to be able to provide those videos online by the end of the week, or at worst at the beginning of next week.

Kernel Developer Panel. From left to right: Linus Torvalds, Paul McKenney, Alan Cox, Thomas Gleixner and the moderator, Lennart Poettring

As we also announced, I gave two talks at this Embedded Linux Conference Europe event. One on Buildroot, titled Using Buildroot for real projects, which slides are available on the elinux.org site. More than 50 persons attended the conference which seems to indicate that there is interest around Buildroot. I had a few questions but unfortunately had to stop the conference after just 2/3 questions since I had exhausted my time slot. My second conference was titled Qt for non-graphical applications, and the slides are also available on the elinux.org site. About 45-50 persons attended the conference and in this case as well, I had to speak quite fast to make the 40+ slides discussion fit within the time slot allocated for the conference, which gave only the time for a few questions at the end. Generally speaking, these talks have attracted a nice number of attendees compared to many other talks I’ve seen, so it seems that all the preparation work was not done needlessly.

Nicolas Deschene (TI) and Loïc Minier (Linaro)

If you couldn’t attend ELCE and are waiting for the videos, I’m sure you’ll also be interested by the date and locations of the next editions of the conference :

The next Embedded Linux Conference, US edition, will take place on February 14-16 2012 in Redwood City, near San Francisco in California. This is an unusual date for the ELC (which traditionally took place in April), but it allows the conference to match with the Linaro Connect event for the first quarter of 2012.
The next Embedded Linux Conference Europe will take place on November 6-9 2012 in Barcelona, Spain. This is a just a ~4h drive from Toulouse, so definitely, several Bootlin people should be there.

Bootlin at Embedded Linux Conference Europe 2011

The next Embedded Linux Conference Europe will take place from October 26th to October 28th in Prague, together with the first edition of LinuxCon Europe and just after the Kernel Summit, the GStreamer conference and the Real-time Linux workshop: it’s a really impressive concentration of interesting talks for embedded Linux developers. Linus Torvalds is already announced as a keynote speaker of the LinuxCon Europe.

ELCE 2011

As ELCE is a conference that embedded Linux developers simply can’t miss, the complete team of Bootlin will be there: my colleague and Bootlin founder Michael Opdenacker (Michael is part of the organization committee for this event), my engineer colleagues Grégory Clément and Maxime Ripard and myself, Thomas Petazzoni.

I will also have the chance to give two talks during this edition of ELCE:

Using Buildroot for real products. As Bootlin has used and is using Buildroot for multiple customer projects, this talk will share our experience on how to configure and setup Buildroot properly to build embedded Linux systems and include in a clean and nice way all of the specificities of each product.
Using Qt for non-graphical applications. Qt is often seen only as a graphical library, but it is in fact much more than that. Based on the experience of a customer project, this presentation will detail all the nice features that Qt offers to build embedded applications.

We highly recommend this conference to European embedded Linux developers and hope to meet some of our readers there! We will be the guys behind the video cameras in the embedded rooms. It’s worth mentioning that ELCE attendees are also granted, for free, the right to access LinuxCon Europe talks.

Buildroot 2011.08 released!

Buildroot logo As promised by the time-based release schedule, a new version 2011.08 of Buildroot has just been released. For those just coming in, Buildroot is a utility that automates the process of building an embedded Linux system: generating a cross-compilation toolchain or importing an existing one, cross-compiling multiple user-space libraries or applications, generating a root filesystem image and building the kernel or bootloader images. We use it extensively at Bootlin for various projects and therefore contribute regularly to this project.

The major highlights of this version are :

An updated version of udev. For a long time, Buildroot has been stuck with an ancient udev release, due to the slightly more complicated dependencies of newer udev versions. Fortunately, Yegor Yefremov and other contributors have done the work to integrate those dependencies and get a modern version of udev to work in Buildroot.
An updated version of util-linux has been integrated. Here as well, updating it wasn’t completely straightforward, due to utility libraries such as libuuid, which is also present and e2fsprogfs, and used by multiple other packages.
The conversion of the Linux kernel build process and the bootloaders build process to the GENTARGETS infrastructure of Buildroot. This makes the build process of the kernel and the bootloaders much more similar to regular packages, and allows to provide the capability of fetching kernel sources not only from tarballs over http/ftp, but also from Git or Subversion repositories.
The kernel build process has been extended to support Linux 3.x versions and also release candidates versions.
Some improvements for using Buildroot to generate systems for non-MMU targets
Some new packages have been added: acl, attr, ebtables, gnutls, inotify-tools, ipset, libargtable2, libiqrf, libmnl, libnspr, libnss, libroxml, libyaml, live555, mxml, orc, rsyslog, sredird, statserial, stunnel, ti-utils, uboot-tools, yajl, and many, many packages have been upgraded or fixed.

The amount of patches merged for this release (287) is almost identical to the number of patches for the past release (286), but the number of contributors has increased from 28 to 35. Generally speaking, we are seeing an increasing number of requests and contributions from users :

   143  Peter Korsgaard
    36  Thomas Petazzoni
    21  Sven Neumann
    13  Gustavo Zacarias
    13  Yegor Yefremov
     9  Maxime Ripard
     7  Yann E. MORIN
     4  Baruch Siach
     4  Daniel Mack
     4  Luca Ceresoli
     3  Jean-Christophe PLAGNIOL-VILLARD
     3  Thomas De Schampheleire
     2  Allan W. Nielsen
     2  Mike Williams
     2  Phil Edworthy
     2  Will Newton
     1  Arnout Vandecappelle (Essensium - Mind)
     1  Arnout Vandecappelle (Essensium/Mind)
     1  Benoit Mauduit
     1  Benoît Mauduit
     1  Daniel Hobi
     1  Daniel Nyström
     1  Danomi Mocelopolis
     1  Evgeni Dobrev
     1  Francis Mendes
     1  Frederic Bassaler
     1  Frederik Pasch
     1  H Hartley Sweeten
     1  Heiko Helmle
     1  Marek Belisko
     1  Michael J. Hammel
     1  Milton Soares Filho
     1  Philippe Reynes
     1  Robin Holt
     1  Tristan Lelong

Two developers from Bootlin have contributed patches for this release: my colleague Maxime Ripard has contributed 9 patches (Python build fixes, toolchain configuration fix, new rsyslog package, rework of the logging init scripts, new stunnel package, /dev/shm fix for the initialization scripts, code cleanup) and I (Thomas Petazzoni) have contributed 36 patches (conversion of the kernel and bootloaders to the GENTARGETS infrastructure, support for Linux 3.x and release candidates, improvements for non-MMU targets, the new scons package, upgrade of valgrind, some other code cleanup and fixes).

For the next release, I expect to contribute a set of patches that has already been reviewed on the list, and which adds the possibility of building packages from an existing source directory instead of letting Buildroot handle the download/extract/patch part of the build process. This feature will make it much much easier to use Buildroot during the development of the kernel, an application or a library for the target embedded system. I have also posted patches that convert the documentation over to the asciidoc format and I intend to do various additions to this documentation.

It is also worth mentioning that the Buildroot developers (Peter Korsgaard and myself) and the Crosstool-NG maintainer Yann E. Morin are organizing a Developer Day on October, 29th in Prague, the day after the Embedded Linux Conference Europe. All developers or users interested in Buildroot and/or Crosstool-NG are invited to join. See http://lists.busybox.net/pipermail/buildroot/2011-August/045066.html for more details.

uClibc 0.9.32 released, with NPTL support

A little bit more than one year after 0.9.31, the uClibc project has recently released a new version of the famous C library, uClibc 0.9.32. For the record, uClibc is an alternative standard C library for embedded Linux systems, which features a smaller size than the usual glibc or eglibc, a high-level of configurability and support for non-MMU architectures. uClibc usage is mandatory on non-MMU architectures running a Linux kernel since the traditional glibc or eglibc do not support non-MMU architectures. On architectures with MMU, uClibc may also be interesting for its reduced size, and has been used in a large number of systems over the last years.

The 0.9.32 release brings one major new feature : the support of the Native Posix Threads Library for the most common architectures (ARM, MIPS, PowerPC, x86, x86_64, SuperH and SuperH 64). NPTL is a different way of implementing the pthread userspace API than the one previously used in Linux, called LinuxThreads. The kernel mechanisms needed to implement NPTL have been added in 2.6 and support in glibc has been added a long time ago. uClibc was lagging behind in this area, and the new release fills this gap. This feature does not bring any visible API change, but completely changes the internal implementation of the threading mechanism, with better performance and a behavior that is more similar to the one we have on glibc based hosts. For more details about the differences about NPTL and LinuxThreads, one can check Ulrich Drepper and Ingo Molnar’s paper on this topic: NPTL Design paper.

Another new feature of the 0.9.32 release is support for the C6x architecture, which is a DSP architecture from Texas Instruments, capable of running a Linux kernel (see http://linux-c6x.org). Having upstream support in uClibc allows this architecture to benefit from a nice standard C library.

Buildroot 2011.05 released

Buildroot logo As expected with the time-based releases, Buildroot 2011.05 has been released just a few days ago. We have already published many blog posts about Buildroot, but to summarize for our new readers, Buildroot is a tool that automates and simplifies the process of building an embedded Linux system. You define your system configuration and components in a menuconfig/xconfig interface similar to the one the kernel uses, then hit make, wait a bit, and you have your embedded Linux system ready to run on your device. At Bootlin, we appreciate the simplicity of Buildroot, and many of our customers also appreciate it for the same reason. Of course, we also contribute significantly to Buildroot and we have started a commercial support offering on Buildroot.

The 2011.05 release

The 2011.05 release cycle was a little bit more quiet than usual, so the number of new features or major changes is not as large as it was for past releases. Amongst the interesting things:

Until now, Buildroot was only capable of building systems using a static /dev, in which device files are statically listed in a device table and created at system build time. The 2011.05 has added a configuration option to select how the /dev directory on the target should be handled. It can be handled in four different ways:
- with a static /dev, just as before
- with just devtmpfs. It allows to have a dynamic /dev without any other userspace components, which is really nice.
- with devtmpfs and mdev. In addition to having a dynamic /dev, it allows allows to execute arbitrary scripts when device are added/removed and to customize the owner, group and permissions for the device files.
- with devtmpfs and udev. This is the full solution, as used in desktop distributions.
There has been an internal infrastructure change on support for external toolchains, and this change will make those toolchains slightly easier to use. In Buildroot terminology, an external toolchain is a toolchain that hasn’t been built by Buildroot, but which Buildroot uses to compile code for the target platform. It allows to re-use existing toolchains such as the CodeSourcery toolchains, or toolchains generated externally with Crosstool-NG. To support those toolchains, we rely on the sysroot mechanism that the GCC compiler provides since the 4.x era. This mechanism allows Buildroot to make a complete copy of the C library binaries, C library headers and kernel headers into a staging directory, and then tell the toolchain utility (compiler, linker, etc.) to use this new directory as their sysroot. This means that a --sysroot option needs to be passed at every invocation of those tools. As this was not very convenient, especially to use the Buildroot toolchain as a SDK to build applications not packaged in Buildroot, the 2011.05 has added wrappers for the toolchain tools, which makes this completely transparent. So one can now just use $(O)/host/usr/bin/arm-linux-gcc as usual, and it will do the right thing.
A few new packages have been added: bonnie++ (a block device benchmark), can-utils (userspace utilities for the famous industrial CAN bus), gdisk (a sort of fdisk program, but for the new GPT partition table format), htop (a nice top alternative to watch the activity of processes), input-event-daemon (a simple daemon that executes arbitrary command in reaction to input events), libexif (a library to read the contents of EXIF tags in pictures), libraw (a library to decode pictures in various RAW formats), libv4l (the library to interact with Video4Linux devices), ngircd (an IRC server).
Many packages have been upgraded: the Gtk stack, the U-Boot and Barebox bootloaders and the internal toolchain components (gcc and uClibc), with experimental gcc 4.6 support.

Buildroot in the Linux Journal

The Linux Journal has published an issue, numbered 206, dedicated to Embedded Linux. This issue has several articles around Embedded Linux related topics:

Hexapod, a Linux powered robot
Debugging Embedded Linux platforms with Python and GDB
Breaking free the Gumstix DSP
Speech I/O for Embedded Applications
CyanogenMod 7.0, Gingerbread in the house
Tiny Core Linux
Roll your own Embedded Linux System with Buildroot, written by Alexander Sirotkin, which gives a good introduction to what Buildroot is and how to use it.

It is great to see articles about Buildroot in a such widely read magazine, and it should definitely help increasing the awareness about this build system.

Buildroot used by Fabrice Bellard in jslinux

In May, the famous developer Fabrice Bellard (known as the initial author of ffmpeg, qemu, but also for his records for the computation of pi) has released an impressive new project: an x86 emulator completely written in Javascript, which runs in a Web browser. This emulator is sufficiently capable and powerful to boot a Linux system. And the good news is that the Linux system that Fabrice Bellard is using for the demonstration was generated with Buildroot, as Bellard says in his technical notes about the project.

Embedded Linux training: switch to the IGEPv2 board

Since early 2009, our training sessions have been using the USB-A9263 board from Calao Systems as the hardware platform for the practical labs. However, this AT91-based platform was getting older, and we therefore started the process of switching our training sessions to a new hardware platform, the IGEPv2 board from ISEE.

The IGEPv2 platform is very similar to the popular BeagleBoard and BeagleBoard-XM platforms, and has the following technical characteristics :

TI DM3730, which is the latest OMAP3 processor from Texas Instruments, clocked at 1 Ghz, and including a DSP for signal processing, an IVA block for audio/video decoding and the PowerVR SGX for 3D/OpenGL. This processor offers far more possibilities than the AT91 one, especially for multimedia applications.
512 MB of RAM and 512 MB of OneNAND flash.
Integrated Ethernet connector, Wifi and Bluetooth connectivity.
One USB OTG port and one USB host port.
A microSD connector.
A DVI-D connector (HDMI), stereo input and ouput
RS232 connector
Multiple expansion ports to access LCD, camera, I2C, SPI, JTAG, etc. signals

Compared to the BeagleBoard-XM, this board has the following advantages:

it has a OneNAND Flash device, which allows us to demonstrate and practice the usage of MTD and Linux flash-specific filesystems such as JFFS2 and UBIFS in our training sessions. Even though block-based storage such as SD and eMMC is more and more popular in consumer-electronic devices, usage of raw NAND flash is still very common in industrial applications, and we therefore wanted to keep presenting those devices and their usage in embedded Linux
ISEE, the company manufacturing the IGEPv2, is located in Spain, which makes it easier for us to regularly order boards from them, since we are also located in Europe
the board provides Bluetooth and Wifi connectivity, which is nice

We have already given two sessions of our Embedded Linux system development training with the IGEPv2, and all our future sessions of this training will use this hardware platform, so the participants will benefit from a more modern platform, with far more capabilities than our previous AT91-based training hardware. This is also the board we are now giving to the participants to our public training sessions, so those participants come back home with a very nice and powerful platform which allows countless experiments around embedded Linux. Note that we also intend to port our Embedded Linux kernel and driver development training session to the IGEPv2 platform in the near future.

Embedded Linux boot time reduction presentation for GENIVI

I was invited to speak at the GENIVI All Members Meeting that took place on May 3-6 in Dublin, Ireland. This was a very interesting opportunity to meet new people in the In Vehicle Infotainment (IVI) industry and community.

In addition to the friendly social event at the Guiness Brewery, there was also a very interesting technical showcase of products and software using the GENIVI stack. I could observe that Freescale and ARM chips in general dominate this market. I also wore my Linaro shirt and had interesting discussions with several people about partnership opportunities between GENIVI and Linaro.

I gave a presentation about reducing boot time in embedded Linux systems. The slides are available in PDF and ODF formats, and as usual, are released with a Creative Commons Attribution – Share Alike 3.0 license. Here is the description of the talk:

Cheap Linux boot time reduction techniques

By Michael Opdenacker, Bootlin

More and more feature rich Linux devices are put in the hands of consumers, and the average consumer shouldn’t even notice that they run Linux. To make the OS invisible, the system should boot in a flash.

Multiple boot time reduction techniques are now available, and can be used at the end of a development project, without incurring redesign costs. This presentation will guide embedded Linux system developers through the most effective ones. For each technique, we will detail how to use it and will report the exact savings achieved on a real embedded board.

Author’s biography

Michael Opdenacker is the founder of Bootlin (https://bootlin.com), a company offering development, consulting and training services to embedded Linux system developers worldwide. He is always looking for innovative techniques to share with customers and with the community.

Michael is also the Community Manager for Linaro (http://linaro.org), a not-for-profit engineering organization working on software foundations for Linux on ARM, to reduce fragmentation between ARM chip vendors, increase product performance and reduce time to market. Linaro currently employs more than 100 of the most active developers in the ARM and embedded Linux community.

I was pleased to have a good number of participants, and to get many questions during and after the talk.

Though GENIVI is about Free and Open Source Software, it is unfortunately not very open to the community yet. You have to become a member to access its specifications, wiki and other technical resources. While collecting membership fees makes sense to operate such an organization, and is acceptable for system makers, it makes it difficult for embedded Linux community developers to get involved. I hope that GENIVI will become more open to the wider embedded Linux community in the future.

Videos of Android Builders Summit 2011

Just after the Embedded Linux Conference 2011, the first edition of the Android Builders Conference took place in San Francisco, on April 13th and April 14th 2011. This is the first, and to date, probably the first, conference entirely dedicated to Android low-level components and on how Android systems are built and modified. The number of resources, documentation and conferences on Android application development is already huge, but the amount of system-level information about Android is still relatively limited. This conference comes to fill in this gap, allowing engineers working on Android-based systems to share their experience. With a single track of talks for the first half-day, and two tracks for the second full day, it was a very nice first edition, and the co-location with the Embedded Linux Conference was well-appreciated. Interestingly enough, no talks were given by Google engineers, despite the fact that they are the primary designers and developers of the Android system.

Just as we did for the Embedded Linux Conference a few days ago, we are also publishing below the videos of all talks given during this Android Builders Summit. Of all the presentations, the ones we found the most interesting are certainly:

Karim Yaghmour’s talk about « Android Internals » and «Porting Android to new hardware»
Aleksander “Sasa” Gargenta’s talk «A walk through the Android stack». Unfortunately, the speaker had way too much contents for the one hour slot, but the content presented was very, very interesting.
Mark Brown’s talk «Linux audio for smartphones»

Mike Woster
Linux Foundation
Android Builders Summit Introduction
Video (2 minutes):
full HD (31M), 450×800 (11M)

Christy Wyatt
Motorola
Motorola: innovation rising
Video (36 minutes):
full HD (454M), 450×800 (142M)

Mark Charlebois
Qualcomm Innovation Center
From the alliance to the evolution: the history and future of Android innovation
Video (26 minutes):
full HD (332M), 450×800 (103M)

Greg Burns
QuIC
AllJoyn and the new era of peer-to-peer-technology
Video (55 minutes):
full HD (680M), 450×800 (209M)

Mark Brown
Wolfson Micro
Linux audio for smartphones
Slides
Video (46 minutes):
full HD (560M), 450×800 (173M)

Karim Yaghmour
Opersys
Android Internals
Slides
Video (58 minutes):
full HD (793M), 450×800 (245M)

Mark Gross
Intel
Device provisioning anad over the air updates for Android-2011
Slides
Video (48 minutes):
full HD (847M), 450×800 (214M)

Peter Vescuso
Black Duck Software
Managing Android and the complexity inside
Video (35 minutes):
full HD (375M), 450×800 (121M)

Hansung Chun
ETRI
I/O performance improvement, using ext2 in Android-2011
Slides
Video (44 minutes):
full HD (915M), 450×800 (210M)

Magnus Bäck
Sony Ericsson
Using the Debian package manager to assemble Android-based phone software systems
Video (45 minutes):
full HD (357M), 450×800 (134M)

Tim Bird
Sony Network Entertainment
Trying to improve Android boot time with readahead
Slides
Video (38 minutes):
full HD (833M), 450×800 (194M)

Bruce Beare
Intel
Living with Gerrit
Slides
Video (42 minutes):
full HD (404M), 450×800 (137M)

Karim Yaghmour
Opersys
Porting Android to new hardware
Slides
Video (43 minutes):
full HD (822M), 450×800 (209M)

Marko Gargenta
Marakana
Beyond the phone
Slides
Video (44 minutes):
full HD (682M), 450×800 (193M)

Neil Trevett
NVIDIA
Open API standards as a foundation for Android innovation
Video (42 minutes):
full HD (523M), 450×800 (173M)

Vitaly Wool, presented by Mark Gross
Sony Ericsson
WiFi and Android: powersave saga
Video (31 minutes):
full HD (544M), 450×800 (136M)

Aleksander “Sasa” Gargenta
Marakana
A walk through the Android stack
Video (60 minutes):
full HD (689M), 450×800 (234M)

Armijn Hemel
gpl-violations.org
Licensing pitfalls in Android and how to avoid them
Video (44 minutes):
full HD (662M), 450×800 (183M)

Tim Bird
Sony Network Entertainment
Android System Programming Tips and Tricks
Slides
Video (42 minutes):
full HD (459M), 450×800 (153M)

In agreement with the speakers, these videos are released under the terms of the Creative Commons Attribution-ShareAlike 3.0 license.