ELC 2011 videos

The Embedded Linux Conference 2011 took place between April, 11th and April, 13th in its now usual place, the Kabuki hotel in San Francisco, California. It was the first edition organized since the merge of the CE Linux Forum into the Linux Foundation. During three days, three parallel tracks of talks and BoFs about technical topics around embedded Linux : kernel support, power management, build systems, file systems, real-time, and more.

As usual, part of the Bootlin team was at this Embedded Linux Conference, in order to keep up with the latest developments from the embedded Linux community. Gregory Clement (left on the picture), Maxime Ripard (right on the picture) and myself (center on the picture) were present, and we recorded all talks of the conference. And just a little bit more than one month later, we are ready to announce that all videos are now available online, in 1080p high-definition, and in a lower 450p resolution, encoded with the new VP8 codec.

Bootlin at ELC 2011
Bootlin at ELC 2011. From left to right: Gregory Clement, Thomas Petazzoni and Maxime Ripard.

Amongst all the conferences below, each of us have selected the three ones we thought were the most interesting ones (note that the top three for each us is necessarily composed of distinct talks, as none of us have seen the same talks since we had to record talks from three different sessions in parallel) :

  • For Gregory Clement, the top three is: Yoshiya Hirase talk about Faster Resume For More Energy Savings on MeeGo, Arnd Bergmann talk about Optimizations For Cheap Flash Media (which follows Arnd article on the same topic in LWN) and a set of three related talks about the video infrastructure in the Linux kernel, that Gregory recommends to watch in this order: Media Controller Framework (MCF) For OMAP2+ Display Subsystem (Sumit Semwal), Video4linux: Progress, New videobuf2 Framework and the Future (Hans Verkuil) and Bringing up HDMI Display for OMAP4 Panda Board – Design, Challenges and Lessons Learned (Mythri pk).
  • For Maxime Ripard, the top three is: John Stultz talk about Android for servers, Mike Anderson talks about ARM NEON and GPU programming, Wolfram Sang talk about Helping the process
  • For myself, the top three is: Jesse Barker talks about the ARM Graphics ecosystem which gives a nice overview of the state of this topic, Hai Shalom talk about PCD (which is an original and interesting replacement for init), Dave Stewart talk about The Yocto Project and its Application Development Toolkit (because it gives details on how Yocto is supposed to be used for application development, a topic I’m interested in as a Buildroot developer)

It is also worth noting that this Embedded Linux Conference was co-located with the first edition of the Android Builders Summit, for which we will soon publish videos as well. The next embedded Linux conference will take place in Europe, in Prague from October 26th to 28th, co-located with the first edition of LinuxCon Europe and just after the Kernel Summit. Prague will really be full of Linux developers during this end of October, it’s time to book this week on your agenda as well !

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

Finally, the list of all videos of Embedded Linux Conference 2011, along with their corresponding slides :

Tim BirdVideo capture
Sony Network Entertainment
Welcome Keynote
Video (10 minutes):
full HD (131M), 450×800 (43M)

Dirk Hohndel, Richard PurdieVideo capture
Intel, Linux Foundation
The Yocto Project
Video (35 minutes):
full HD (458M), 450×800 (140M)

Keshava MunegowdaVideo capture
Texas Instruments
Power Fail Safe FAT File Systems
Slides
Video (48 minutes):
full HD (693M), 450×800 (203M)

Frank RowandVideo capture
Sony
Identifying embedded real-time issues: I-cache and locks
Slides
Video (46 minutes):
full HD (471M), 450×800 (147M)

Bruno Cardoso LopesVideo capture
University of Campinas
LLVM, Clang and Embedded Linux Systems
Slides
Video (50 minutes):
full HD (593M), 450×800 (164M)

Steven RostedtVideo capture
RedHat
Kernel Shark Tutorial
Video (49 minutes):
full HD (743M), 450×800 (215M)

Kang DongwookVideo capture
ETRI
Snapshoot Booting on Embedded Linux
Slides
Video (33 minutes):
full HD (284M), 450×800 (95M)

Khem RajVideo capture
State of OpenEmbedded Internal Toolchain and SDKs
Slides
Video (41 minutes):
full HD (289M), 450×800 (119M)

David RuslingVideo capture
Linaro
Linaro: a year of change
Slides
Video (50 minutes):
full HD (529M), 450×800 (173M)

Hai ShalomVideo capture
Atheros
Control, recover and debug your embedded product with PCD
Slides
Video (50 minutes):
full HD (470M), 450×800 (160M)

Gene SallyVideo capture
Zigbee Networking and Linux
Video (53 minutes):
full HD (262M), 450×800 (139M)

Xi WangVideo capture
Broadcom
Solving real-time scheduling problems with RT_PREEMPT and deadline-based scheduler
Slides
Video (43 minutes):
full HD (422M), 450×800 (141M)

Mike AndersonVideo capture
The PTR Group
ARM Neon instruction set and why you should care
Slides
Video (53 minutes):
full HD (527M), 450×800 (169M)

Darren HartVideo capture
Intel
Yocto Project: Practical Kernel Development Tutorial
Video (52 minutes):
full HD (551M), 450×800 (196M)

Arnd BergmannVideo capture
IBM
Optimizations for cheap flash media
Slides
Video (49 minutes):
full HD (482M), 450×800 (160M)

Wolfram SangVideo capture
Pengutronix
Developer’s diary: helping the process
Slides
Video (39 minutes):
full HD (315M), 450×800 (112M)

Rajesh LalVideo capture
Nokia
Fun with QML and Javascript
Slides
Video (39 minutes):
full HD (250M), 450×800 (108M)

Thomas GleixnerVideo capture
Linutronix
RT-Preempt: what’s the state and why there is no roadmap
Slides
Video (46 minutes):
full HD (447M), 450×800 (149M)

Jason KridnerVideo capture
Texas Instruments
High-level web interface to low-level I/O on the BeagleBoard
Slides
Video (36 minutes):
full HD (370M), 450×800 (115M)

Arnd BergmannVideo capture
IBM
Becoming part of the Linux kernel community
Slides
Video (34 minutes):
full HD (376M), 450×800 (126M)

Paul MundtVideo capture
Renesas
Working with hardIRQs: life beyond static IRQ assignments
Slides
Video (36 minutes):
full HD (330M), 450×800 (113M)

Amit KucheriaVideo capture
Linaro
Powerdebugging inside Linaro
Slides
Video (46 minutes):
full HD (309M), 450×800 (136M)

Mike AndersonVideo capture
The PTR Group
High-performance computing using GPUs
Slides
Video (57 minutes):
full HD (615M), 450×800 (185M)

Paul LarsonVideo capture
Canonical
Linaro automated validation on ARM
Video (51 minutes):
full HD (581M), 450×800 (184M)

Dave StewartVideo capture
Intel
The Yocto project and its application development toolkit (ADT) – The answer to effective embedded application development
Video (42 minutes):
full HD (362M), 450×800 (139M)

Damian Hobson Garcia, Katusya Matsubara, Takanari Hayama, Hisao MunakataVideo capture
Igel
Integrating a Hardware Video Codec into Android Stagefright using OpenMAX IL
Slides
Video (55 minutes):
full HD (564M), 450×800 (177M)

Koen KooiVideo capture
Texas Instruments
Integrating OpenEmbedded and Yocto
Slides
Video (52 minutes):
full HD (465M), 450×800 (159M)

Mark GrossVideo capture
Intel
How to power tune a device running on a Linux kernel for better suspend battery life
Slides
Video (49 minutes):
full HD (273M), 450×800 (129M)

Remi LorriauxVideo capture
Adeneo Embedded
Real-time audio on embedded devices
Slides
Video (44 minutes):
full HD (437M), 450×800 (138M)

Magnus DammVideo capture
Runtime PM: upstream I/O device power management
Slides
Video (53 minutes):
full HD (486M), 450×800 (164M)

Jesse BarkerVideo capture
Linaro
Linux graphics meets the ARM ecosystem
Slides
Video (50 minutes):
full HD (329M), 450×800 (147M)

David AndersVideo capture
Texas Instruments
Board bringup: open-source hardware and software tools
Slides
Video (38 minutes):
full HD (376M), 450×800 (118M)

John WilliamsVideo capture
PetaLogix
Dynamic co-simulation of FPGA-based systems on chip
Slides
Video (57 minutes):
full HD (567M), 450×800 (198M)

Summit SemwalVideo capture
Texas Instruments
Media Controller Framework (MCF) for OMAP2+ display subsystem
Slides
Video (49 minutes):
full HD (518M), 450×800 (155M)

John StultzVideo capture
IBM
Android for servers?
Slides
Video (37 minutes):
full HD (425M), 450×800 (137M)

Anand GadiyarVideo capture
Texas Instruments
Tools and techniques for debugging embedded systems
Slides
Video (30 minutes):
full HD (139M), 450×800 (81M)

Hans VerkuilVideo capture
Cisco
Video4linux: progress, new videobuf2 framework and the future
Slides
Video (56 minutes):
full HD (534M), 450×800 (171M)

Yoshiya HiraseVideo capture
Nokia
Faster resume for more energy saving on MeeGo
Slides
Video (58 minutes):
full HD (727M), 450×800 (218M)

Jake EdgeVideo capture
Linux Weekly News
What embedded Linux developers should know about IPv6
Slides
Video (46 minutes):
full HD (266M), 450×800 (122M)

Grégoire GentilVideo capture
Always Innovating
Hot multi-OS switch: how to run Ubuntu, ChromiumOS, Android at the same time on an embedded device
Video (61 minutes):
full HD (515M), 450×800 (174M)

Xi WangVideo capture
Broadcom
Controlling memory footpring at all layers: Linux kernel, applications, libraries and toolchain
Slides
Video (38 minutes):
full HD (511M), 450×800 (152M)

Tom Zanussi, Saul WoldVideo capture
Building custom embedded images with Yocto
Slides
Video (49 minutes):
full HD (500M), 450×800 (173M)

Philip BalisterVideo capture
Open SDR
A high performance interface between the OMAP3 and a FPGA
Slides
Video (51 minutes):
full HD (347M), 450×800 (149M)

Jean PihetVideo capture
NewOldBits.com
The evolution of tracing and profiling for power management and accelerators
Slides
Video (40 minutes):
full HD (428M), 450×800 (133M)

Elizabeth FlanaganVideo capture
Intel
Delivering predictability: the Yocto project autobuilder, automated sanity testing, license collection and build statistics tracking
Slides
Video (48 minutes):
full HD (241M), 450×800 (133M)

Mythri pkVideo capture
Texas Instruments
Bringing up HDMI display for OMAP4 Panda board: design, challenges and lessons learned
Slides
Video (40 minutes):
full HD (363M), 450×800 (122M)

Khem RajVideo capture
Debug/develop uClibc with QEMU
Slides
Video (35 minutes):
full HD (226M), 450×800 (98M)

Gunter Ravi SankarVideo capture
Samsung
What are and how to find a program’s unused DSOs
Slides
Video (49 minutes):
full HD (453M), 450×800 (143M)

Videos from the FOSDEM 2011 Embedded track

As every year, FOSDEM, the largest community-driven open source conference in Europe, took place early February in Brussels. And again, Bootlin was around with its HD camcorder, to record the conferences of interest for embedded developers. They are now available for download!

FOSDEM banner

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

Here are the videos that we have (unfortunately, the FOSDEM team doesn’t collect and publish the slides from the speakers) :

Creating and flashing UBI / UBIFS images

Flash super heroEmbedded-oriented filesystems are a scattered world. Flash-optimized filesystems are less so. JFFS2 has been widely used but has several performance issues (mount time, especially, though CONFIG_SUMMARY and sumtool fixes that since 2.6.15). LogFS doesn’t seem to be actively maintained. The most active and promising flash filesystem is UBIFS. It runs on top of UBI (“Unsorted Block Images”), an abstraction layer for MTD devices.

Why flash-oriented filesystems ?

MTDs (Memory Technology Devices) are very different from block devices: instead of a sequence of writable sectors, they contain an array of writable pages, organized in so-called “erase blocks”.

To write on a page that already has data on it, you first have to erase this data. However, it is only possible to erase whole eraseblocks. Only then, you can write your new data (including what you didn’t change). Erasing causes the memory cells to wear out. At some point, they won’t be usable anymore and have to be skipped.

Because it is memory-based, random access is theoretically as fast as sequential access. So, you don’t need to keep the fragments of your files together. It makes it possible to do wear-leveling and thus, “increase” the lifetime of the chip.

A simple way of doing wear-leveling is to keep track of the number of times a block has been erased and use the block that has been the least erased when updating data.

All these constraints make it hard to write a flash filesystem.

UBI intends to deal with all MTD-specific operations while still presenting random-access volumes to the the upper-layer. The first – and as for now, only – implementation using UBI is UBIFS. UBI is a “volume manager” and maps physical erase blocks (PEB) to logical erase blocks (LEB). The LEBs are smaller than the PEBs because of meta-data and headers.

How to use UBI on my board ?

There are mainly 2 ways to do that:

  • On a booted Linux system, approximately the same way you would create a partition on your desktop’s hard drive ;
  • From the bootloader, by flashing a previously prepared UBI image ;

Whatever solution you choose, you need to know the sizes of:

  • the eraseblocks (PEB) ;
  • the pages (or “minimum input/output size”) ;
  • the subpages (it may be the same as the min i/o size) ;

From these details, you can deduce another one: the size of logical erase blocks. It is the size of the PEB minus a data offset which is:

(int((Subpage_size + Page_size) / Page_size))  * Page_size

(subpage+page truncated to page size). This formula makes some assumption but should be correct if the subpage size is more than 8B and the page size more than 64B (see the source for more information). The best way to be sure of this size is to use mtdinfo on linux on the board. mtdinfo is part of the ubi-utils (part of mtd-utils). It’s probably available in your build system.

In both cases, you will also need a UBIFS image. In the way of JFFS2, mkfs.ubifs comes in mtd-utils (thus, you also need them on your desktop. Warning: mtd-utils in Ubuntu 10.10 are reported to be buggy ; if you use this distribution, recompile them from their git tree). Here is an example of how you can invoke it:

# mkfs.ubifs -r </path/to/your/rootfs/tree> -m <min io size>
  -e <LEB size> -c <Eraseblocks count>
  -o </path/to/output/ubifs.img>

Solution A – On a booted Linux system

I think it’s the best method to understand how UBI is structured.

You first need to enable UBI and UBIFS in the kernel and install the mtd-utils package (for Debian and Ubuntu) on your box. You may also compile mtd-utils from its sources.

Once you have your UBIFS image at hand, let’s sing the UBI song:

# ubiformat /dev/mtdX
# ubiattach -p /dev/mtdX
# ubimkvol /dev/ubi0 -N volume_name -s 64MiB
# ubiupdatevol /dev/ubi0_0 /path/to/ubifs.img
# mount -t ubifs ubi0:volume_name /mount/point

Let’s examine each command. ubiformat erases an MTD partition but keeps its erase counters ((‘X’ is the number of the partition you want to use). ubiattach creates a UBI device from the MTD partition. This UBI device is then referred to by UBI as ubi0 (if it is the first device). ubimkvol creates a volume on a UBI device ; this volume is referred to as ubi0_0 (if it is the first volume on the device). ubiupdatevol puts an image on an empty volume. (use ubiupdatevol -t /dev/ubi0_0 to empty a volume). At last, the well-known mount can be invoked using <device>:<volume>

Solution B – Prepare a UBI image ready to be flashed

It is more common to directly flash filesystem images directly from the bootloader. It is made possible by ubinize to prepare a UBI device image containing one or more volumes.

ubinize reads a configuration file (in the very simple INI format) describing the volumes and their configuration. Here is an example of a device with two volumes ; one, named rootfs is read-only (static), the other one, data is read-write (dynamic) ; the autoresize flag makes UBI resize to volume to use the whole unused space at initialization. The name of the sections is totally arbitrary.

[rootfs_volume]
mode=ubi
image=rootfs.ubifs
vol_id=1
vol_type=static
vol_name=rootfs
vol_alignment=1

[rwdata_volume]
mode=ubi
image=data.ubifs
vol_id=2
vol_type=dynamic
vol_name=data
vol_alignment=1
vol_flags=autoresize

Next is the generation of the UBI image. The ubinize utility will need the Physical Erase Block size (PEB) (option -p) and the minimum I/O size (-m):

# ubinize -vv -o <output image> -m <min io size>
  -p <PEB size>KiB <configuration file>

Your image is ready. You may now want to boot on the rootfs UBIFS partition. Keep on reading, then.

Use a UBIFS partition as root partition

Some options need to be passed to the kernel to boot on a ubi volume and on a UBIFS partition:

ubi.mtd=<mtd partition number>
root=<ubi device>:<volume>
rootfstype=ubifs

For instance, with the previous examples and assuming the UBI device has been created/flashed on /dev/mtd1:

ubi.mtd=1 root=ubi0:rootfs rootfstype=ubifs

Conclusion

Creating and using a UBIFS filesystem is not as easy as with JFFS2 but UBI/UBIFS is designed to be more robust and UBI will ease the development of new filesystems. The authors of UBI have pointed some memory usage scalability problems but if a second version of UBI were written, filesystems on top of it would not need to be modified.

Troubleshooting

In case your system is missing the /dev/ubi_ctrl, /dev/ubi0 or /dev/ubi0_X device files, we advise you to recompile your kernel with DEVTMPFS and DEVTMPFS_MOUNT. This way, all the devices existing on your system will appear in /dev.

If you get write errors (code -74 or -5, probably), check that CONFIG_MTD_NAND_VERIFY_WRITE (respectively, ONENAND) is disabled : verifying subpages writes isn’t supported yet.

Sources

The primary place for information about MTD support in Linux is infradead.org. There also is a mailing list which you can also subscribe to.

The kernel sources under drivers/mtd and fs/ubisfs are also very helpful.

Videos from Libre Software Meeting 2010 in France

RMLL 2010The Libre Software Meeting (Rencontres Mondiales du Logiciel Libre in French) is a community-driven event that takes place every year in France, and covers a wide range of topics in the free and open source software domain. Each year, an Embedded systems and free hardware topic is proposed, which in 2010 was lead by Florian Fainelli, Pierre Ficheux and myself.

While most of the talks took place in French, a few talks were given in English and as we recoded videos from those talks, we thought it’d be a good idea to highlight them to the english readers of our blog. We found it especially important since amongst those videos, there are two particularly interesting presentations from Sarah Sharp, a kernel developer from Intel, about USB3 and its support in Linux. As usual, all our videos are published under the Creative Commons Attribution – ShareAlike Licence version 3.0 license.

Sarah Sharp presenting USB3 at LSM2010

The talks given in English were :

Our french readers will find all other videos in this blog post.

Building a small Debian root filesystem with Multistrap

There are several ways to build a root filesystem for an embedded Linux system: Buildroot and Open Embedded are the usual solutions to do this. They allow to fine tune the contents of your filesystem. The drawback is, in both cases, that you need to build everything from sources and this can take from tens of minutes to several hours.

Sometimes you don’t need all this flexibility and you just want to have a ready-to-use root filesystem, to which you just add a few extra programs. In this case using a distribution is a good solution. So let’s see what we need:

  • A binary distribution
  • Available on several architectures
  • Ability to generate a “small” root filesystem
  • A large choice of packages

Oh, I think it is a pretty good description of Debian!

Emdebian is a project to adapt Debian to embedded devices. A good description from the Debian wiki is:

“In short, what EmDebian does is wrap around the regular Debian package building tools to provide a more fine grained control over package selection, size, dependencies and content to enable creation of very small and efficient Debian packages for use on naturally resource limited embedded targets.”

And so, pretty recently (2009), Emdebian released Multistrap which is similar to Debootstrap but more appropriate for embedded devices. It seems better by the way it builds a system:

It works in a completely different way by simply using apt and dpkg, rather than avoiding to use them, which is how Debootstrap works.

And also more appropriate by its goals:

It is focused on producing rootfs images for devices, as opposed to chroots for existing machines

Practical case: build a root filesystem for the USB A9263 board from Calao Systems (arm926ejs based board).

A drawback of Multistrap is its limitation to Debian, but in fact it is also usable on any distribution based on Debian. In our case, we ran it on an Ubuntu 10.04 system.

First, let’s install Multistrap:

$sudo apt-get install multistrap dpkg-dev

Multistrap needs a config file. For our needs we just use the example one given by Embedian. Let’s name it multistrap.conf:

[General]
noauth=true
unpack=true
debootstrap=Grip
aptsources=Grip

[Grip]
# space separated package list
source=http://www.emdebian.org/grip
suite=lenny

Grip is the name of the lightweight Debian distro built by Emdebian.

Now we can run Multistrap:

$ multistrap -a armel -d $PWD/RFS -f multistrap.conf
em_multistrap 0.0.8 using multistrap.conf
Using foreign architecture: armel
em_multistrap building armel multistrap on 'amd64'
INF: Setting ./lib64 -> ./lib symbolic link.
Getting package lists: apt-get  -o Apt::Architecture=armel -o Apt::Get::AllowUnauthenticated=true -o Apt::Get::Download-Only=true -o Apt::Install-Recommends=false -o Dir=/home/mike/celf/multistrap/RFS/ -o Dir::Etc=/home/mike/celf/multistrap/RFS/etc/apt/ -o Dir::Etc::SourceList=/home/mike/celf/multistrap/RFS/etc/apt/sources.list.d/multistrap.sources.list -o Dir::State=/home/mike/celf/multistrap/RFS/var/lib/apt/ -o Dir::State::Status=/home/mike/celf/multistrap/RFS/var/lib/dpkg/status -o Dir::Cache=/home/mike/celf/multistrap/RFS/var/cache/apt/ update
Get:1 http://www.emdebian.org lenny Release.gpg [197B]
Ign http://www.emdebian.org/grip/ lenny/main Translation-en_US
Get:2 http://www.emdebian.org lenny Release [21.4kB]
Ign http://www.emdebian.org lenny Release
Ign http://www.emdebian.org lenny/main Packages
Ign http://www.emdebian.org lenny/main Sources
Ign http://www.emdebian.org lenny/main Packages
Ign http://www.emdebian.org lenny/main Sources
Get:3 http://www.emdebian.org lenny/main Packages [293kB]
Get:4 http://www.emdebian.org lenny/main Sources [351kB]
Fetched 665kB in 0s (6,280kB/s)                     
Reading package lists... Done
W: GPG error: http://www.emdebian.org lenny Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY B5B7720097BB3B58
W: Duplicate sources.list entry http://www.emdebian.org/grip/ lenny/main Packages (/home/mike/celf/multistrap/RFS/var/lib/apt/lists/www.emdebian.org_grip_dists_lenny_main_binary-armel_Packages)
Use of uninitialized value within %packages in join or string at /usr/sbin/em_multistrap line 294.
Use of uninitialized value within %keyrings in join or string at /usr/sbin/em_multistrap line 296.
apt-get -y  -o Apt::Architecture=armel -o Apt::Get::AllowUnauthenticated=true -o Apt::Get::Download-Only=true -o Apt::Install-Recommends=false -o Dir=/home/mike/celf/multistrap/RFS/ -o Dir::Etc=/home/mike/celf/multistrap/RFS/etc/apt/ -o Dir::Etc::SourceList=/home/mike/celf/multistrap/RFS/etc/apt/sources.list.d/multistrap.sources.list -o Dir::State=/home/mike/celf/multistrap/RFS/var/lib/apt/ -o Dir::State::Status=/home/mike/celf/multistrap/RFS/var/lib/dpkg/status -o Dir::Cache=/home/mike/celf/multistrap/RFS/var/cache/apt/ install balloon3-config base-files base-passwd bash bsdutils coreutils debianutils diff dpkg e2fslibs e2fsprogs findutils gcc-4.3-base grep grip-config gzip hostname initscripts libacl1 libattr1 libblkid1 libc6 libcap1 libcomerr2 libdevmapper1.02.1 libgcc1 liblocale-gettext-perl libncurses5 libpam-modules libpam-runtime libpam0g libselinux1 libsepol1 libslang2 libss2 libstdc++6 libtext-charwidth-perl libtext-iconv-perl libtext-wrapi18n-perl libuuid1 libvolume-id0 login lsb-base makedev mawk mktemp mount ncurses-base ncurses-bin passwd perl-base procps sed sysv-rc sysvinit sysvinit-utils tar tzdata util-linux zlib1g
Reading package lists... Done
Building dependency tree... Done
The following extra packages will be installed:
  apt debconf debconf-i18n debian-archive-keyring dhcp3-client dhcp3-common gnupg gpgv ifupdown libbz2-1.0 libdb4.6 libncursesw5 libnewt0.52 libpopt0
  libreadline5 libssl0.9.8 libusb-0.1-4 lzma module-init-tools nano net-tools netbase ntpdate readline-common udev wget whiptail
The following NEW packages will be installed:
  apt balloon3-config base-files base-passwd bash bsdutils coreutils debconf debconf-i18n debian-archive-keyring debianutils dhcp3-client dhcp3-common diff
  dpkg e2fslibs e2fsprogs findutils gcc-4.3-base gnupg gpgv grep grip-config gzip hostname ifupdown initscripts libacl1 libattr1 libblkid1 libbz2-1.0 libc6
  libcap1 libcomerr2 libdb4.6 libdevmapper1.02.1 libgcc1 liblocale-gettext-perl libncurses5 libncursesw5 libnewt0.52 libpam-modules libpam-runtime libpam0g
  libpopt0 libreadline5 libselinux1 libsepol1 libslang2 libss2 libssl0.9.8 libstdc++6 libtext-charwidth-perl libtext-iconv-perl libtext-wrapi18n-perl
  libusb-0.1-4 libuuid1 libvolume-id0 login lsb-base lzma makedev mawk mktemp module-init-tools mount nano ncurses-base ncurses-bin net-tools netbase
  ntpdate passwd perl-base procps readline-common sed sysv-rc sysvinit sysvinit-utils tar tzdata udev util-linux wget whiptail zlib1g
0 upgraded, 87 newly installed, 0 to remove and 0 not upgraded.
Need to get 15.4MB of archives.
After this operation, 48.4MB of additional disk space will be used.
WARNING: The following packages cannot be authenticated!
  libstdc++6 libbz2-1.0 readline-common libncurses5 libreadline5 libusb-0.1-4 zlib1g gpgv gnupg debian-archive-keyring apt debianutils dhcp3-common
  libattr1 libacl1 libselinux1 coreutils lzma dpkg perl-base liblocale-gettext-perl libtext-iconv-perl libtext-charwidth-perl libtext-wrapi18n-perl
  debconf-i18n debconf dhcp3-client sed ncurses-bin lsb-base module-init-tools libssl0.9.8 wget hostname net-tools ifupdown mawk libncursesw5 nano netbase
  libcap1 ntpdate libpam-runtime libpam0g libdb4.6 libpam-modules passwd libvolume-id0 udev libslang2 libnewt0.52 libpopt0 whiptail grip-config
  gcc-4.3-base libgcc1 libc6 base-passwd base-files bash diff libcomerr2 e2fslibs libuuid1 libblkid1 libss2 e2fsprogs findutils grep gzip login mktemp
  mount libsepol1 sysvinit-utils initscripts sysv-rc sysvinit tar tzdata util-linux balloon3-config bsdutils libdevmapper1.02.1 makedev ncurses-base procps
Authentication warning overridden.
Get:1 http://www.emdebian.org/grip/ lenny/main libstdc++6 4.3.2-1.1em1 [268kB]
Get:2 http://www.emdebian.org/grip/ lenny/main libbz2-1.0 1.0.5-1em1 [37.2kB]
Get:3 http://www.emdebian.org/grip/ lenny/main readline-common 5.2-3.1em1 [3,202B]
Get:4 http://www.emdebian.org/grip/ lenny/main libncurses5 5.7+20081213-1em1 [165kB]
Get:5 http://www.emdebian.org/grip/ lenny/main libreadline5 5.2-3.1em1 [108kB]
Get:6 http://www.emdebian.org/grip/ lenny/main libusb-0.1-4 2:0.1.12-13em1 [13.7kB]
Get:7 http://www.emdebian.org/grip/ lenny/main zlib1g 1:1.2.3.3.dfsg-12em1 [48.1kB]
Get:8 http://www.emdebian.org/grip/ lenny/main gpgv 1.4.9-3+lenny1em1 [139kB]
Get:9 http://www.emdebian.org/grip/ lenny/main gnupg 1.4.9-3+lenny1em1 [533kB]
Get:10 http://www.emdebian.org/grip/ lenny/main debian-archive-keyring 2010.08.28~lenny1em1 [17.9kB]
Get:11 http://www.emdebian.org/grip/ lenny/main apt 0.7.20.2+lenny2em1 [514kB]
Get:12 http://www.emdebian.org/grip/ lenny/main debianutils 2.30em1 [23.4kB]
Get:13 http://www.emdebian.org/grip/ lenny/main dhcp3-common 3.1.1-6+lenny4em1 [157kB]
Get:14 http://www.emdebian.org/grip/ lenny/main libattr1 1:2.4.43-2em1 [7,706B]
Get:15 http://www.emdebian.org/grip/ lenny/main libacl1 2.2.47-2em1 [14.0kB]
Get:16 http://www.emdebian.org/grip/ lenny/main libselinux1 2.0.65-5em1 [50.0kB]
Get:17 http://www.emdebian.org/grip/ lenny/main coreutils 6.10-6em1 [1,162kB]
Get:18 http://www.emdebian.org/grip/ lenny/main lzma 4.43-14em1 [51.0kB]
Get:19 http://www.emdebian.org/grip/ lenny/main dpkg 1.14.29em1 [405kB]
Get:20 http://www.emdebian.org/grip/ lenny/main perl-base 5.10.0-19lenny2em1 [905kB]
Get:21 http://www.emdebian.org/grip/ lenny/main liblocale-gettext-perl 1.05-4em1 [11.0kB]
Get:22 http://www.emdebian.org/grip/ lenny/main libtext-iconv-perl 1.7-1+b1em1 [11.2kB]
Get:23 http://www.emdebian.org/grip/ lenny/main libtext-charwidth-perl 0.04-5+b1em1 [6,656B]
Get:24 http://www.emdebian.org/grip/ lenny/main libtext-wrapi18n-perl 0.06-6em1 [4,444B]
Get:25 http://www.emdebian.org/grip/ lenny/main debconf-i18n 1.5.24em1 [2,882B]
Get:26 http://www.emdebian.org/grip/ lenny/main debconf 1.5.24em1 [110kB]
Get:27 http://www.emdebian.org/grip/ lenny/main dhcp3-client 3.1.1-6+lenny4em1 [185kB]
Get:28 http://www.emdebian.org/grip/ lenny/main sed 4.1.5-6em1 [23.8kB]
Get:29 http://www.emdebian.org/grip/ lenny/main ncurses-bin 5.7+20081213-1em1 [70.8kB]
Get:30 http://www.emdebian.org/grip/ lenny/main lsb-base 3.2-20em1 [5,888B]
Get:31 http://www.emdebian.org/grip/ lenny/main module-init-tools 3.4-1em1 [44.5kB]
Get:32 http://www.emdebian.org/grip/ lenny/main libssl0.9.8 0.9.8g-15+lenny8em1 [713kB]
Get:33 http://www.emdebian.org/grip/ lenny/main wget 1.11.4-2+lenny2em1 [116kB]
Get:34 http://www.emdebian.org/grip/ lenny/main hostname 2.95em1 [5,808B]
Get:35 http://www.emdebian.org/grip/ lenny/main net-tools 1.60-22em1 [156kB]
Get:36 http://www.emdebian.org/grip/ lenny/main ifupdown 0.6.8+nmu1em1 [18.9kB]
Get:37 http://www.emdebian.org/grip/ lenny/main mawk 1.3.3-11.1em1 [51.2kB]
Get:38 http://www.emdebian.org/grip/ lenny/main libncursesw5 5.7+20081213-1em1 [187kB]
Get:39 http://www.emdebian.org/grip/ lenny/main nano 2.0.7-5em1 [83.6kB]
Get:40 http://www.emdebian.org/grip/ lenny/main netbase 4.34em1 [11.6kB]
Get:41 http://www.emdebian.org/grip/ lenny/main libcap1 1:1.10-14em1 [7,574B]
Get:42 http://www.emdebian.org/grip/ lenny/main ntpdate 1:4.2.4p4+dfsg-8lenny3em1 [36.1kB]
Get:43 http://www.emdebian.org/grip/ lenny/main libpam-runtime 1.0.1-5+lenny1em1 [7,786B]
Get:44 http://www.emdebian.org/grip/ lenny/main libpam0g 1.0.1-5+lenny1em1 [41.0kB]
Get:45 http://www.emdebian.org/grip/ lenny/main libdb4.6 4.6.21-11em1 [531kB]
Get:46 http://www.emdebian.org/grip/ lenny/main libpam-modules 1.0.1-5+lenny1em1 [160kB]
Get:47 http://www.emdebian.org/grip/ lenny/main passwd 1:4.1.1-6+lenny1em1 [267kB]
Get:48 http://www.emdebian.org/grip/ lenny/main libvolume-id0 0.125-7+lenny3em1 [18.2kB]
Get:49 http://www.emdebian.org/grip/ lenny/main udev 0.125-7+lenny3em1 [145kB]
Get:50 http://www.emdebian.org/grip/ lenny/main libslang2 2.1.3-3em1 [266kB]
Get:51 http://www.emdebian.org/grip/ lenny/main libnewt0.52 0.52.2-11.3+lenny1em1 [36.7kB]
Get:52 http://www.emdebian.org/grip/ lenny/main libpopt0 1.14-4em1 [22.3kB]
Get:53 http://www.emdebian.org/grip/ lenny/main whiptail 0.52.2-11.3+lenny1em1 [11.7kB]
Get:54 http://www.emdebian.org/grip/ lenny/main grip-config 0.1.2em1 [11.5kB]
Get:55 http://www.emdebian.org/grip/ lenny/main gcc-4.3-base 4.3.2-1.1em1 [5,496B]
Get:56 http://www.emdebian.org/grip/ lenny/main libgcc1 1:4.3.2-1.1em1 [23.7kB]
Get:57 http://www.emdebian.org/grip/ lenny/main libc6 2.7-18lenny4em1 [4,410kB]
Get:58 http://www.emdebian.org/grip/ lenny/main base-passwd 3.5.20em1 [11.5kB]
Get:59 http://www.emdebian.org/grip/ lenny/main base-files 5lenny7em1 [49.2kB]
Get:60 http://www.emdebian.org/grip/ lenny/main bash 3.2-4em1 [364kB]
Get:61 http://www.emdebian.org/grip/ lenny/main diff 2.8.1-12em1 [59.6kB]
Get:62 http://www.emdebian.org/grip/ lenny/main libcomerr2 1.41.3-1em1 [6,366B]
Get:63 http://www.emdebian.org/grip/ lenny/main e2fslibs 1.41.3-1em1 [91.3kB]
Get:64 http://www.emdebian.org/grip/ lenny/main libuuid1 1.41.3-1em1 [10.8kB]
Get:65 http://www.emdebian.org/grip/ lenny/main libblkid1 1.41.3-1em1 [21.6kB]
Get:66 http://www.emdebian.org/grip/ lenny/main libss2 1.41.3-1em1 [10.9kB]
Get:67 http://www.emdebian.org/grip/ lenny/main e2fsprogs 1.41.3-1em1 [234kB]
Get:68 http://www.emdebian.org/grip/ lenny/main findutils 4.4.0-2em1 [160kB]
Get:69 http://www.emdebian.org/grip/ lenny/main grep 2.5.3~dfsg-6em1 [128kB]
Get:70 http://www.emdebian.org/grip/ lenny/main gzip 1.3.12-6+lenny1em1 [44.0kB]
Get:71 http://www.emdebian.org/grip/ lenny/main login 1:4.1.1-6+lenny1em1 [50.6kB]
Get:72 http://www.emdebian.org/grip/ lenny/main mktemp 1.5-9em1 [5,772B]
Get:73 http://www.emdebian.org/grip/ lenny/main mount 2.13.1.1-1em1 [69.3kB]
Get:74 http://www.emdebian.org/grip/ lenny/main libsepol1 2.0.30-2em1 [96.4kB]
Get:75 http://www.emdebian.org/grip/ lenny/main sysvinit-utils 2.86.ds1-61em1 [17.8kB]
Get:76 http://www.emdebian.org/grip/ lenny/main initscripts 2.86.ds1-61em1 [33.6kB]
Get:77 http://www.emdebian.org/grip/ lenny/main sysv-rc 2.86.ds1-61em1 [13.7kB]
Get:78 http://www.emdebian.org/grip/ lenny/main sysvinit 2.86.ds1-61em1 [46.8kB]
Get:79 http://www.emdebian.org/grip/ lenny/main tar 1.20-1+lenny1em1 [148kB]
Get:80 http://www.emdebian.org/grip/ lenny/main tzdata 2010j-0lenny1em1 [749kB]
Get:81 http://www.emdebian.org/grip/ lenny/main util-linux 2.13.1.1-1em1 [293kB]
Get:82 http://www.emdebian.org/grip/ lenny/main balloon3-config 0.6 [2,400B]
Get:83 http://www.emdebian.org/grip/ lenny/main bsdutils 1:2.13.1.1-1em1 [17.0kB]
Get:84 http://www.emdebian.org/grip/ lenny/main libdevmapper1.02.1 2:1.02.27-4em1 [44.1kB]
Get:85 http://www.emdebian.org/grip/ lenny/main makedev 2.3.1-88em1 [15.8kB]
Get:86 http://www.emdebian.org/grip/ lenny/main ncurses-base 5.7+20081213-1em1 [16.4kB]
Get:87 http://www.emdebian.org/grip/ lenny/main procps 1:3.2.7-11em1 [160kB]
Fetched 15.4MB in 3s (4,819kB/s)
Download complete and in download only mode
I: Calculating obsolete packages
I: Extracting apt_0.7.20.2+lenny2em1_armel.deb...
 -> Processing conffiles for apt
I: Extracting balloon3-config_0.6_all.deb...
I: Extracting base-files_5lenny7em1_armel.deb...
 -> Processing conffiles for base-files
I: Extracting base-passwd_3.5.20em1_armel.deb...
I: Extracting bash_3.2-4em1_armel.deb...
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I: Extracting bsdutils_1%3a2.13.1.1-1em1_armel.deb...
I: Extracting coreutils_6.10-6em1_armel.deb...
I: Extracting debconf-i18n_1.5.24em1_all.deb...
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 -> Processing conffiles for debconf
I: Extracting debian-archive-keyring_2010.08.28~lenny1em1_all.deb...
I: Extracting debianutils_2.30em1_armel.deb...
I: Extracting dhcp3-client_3.1.1-6+lenny4em1_armel.deb...
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I: Extracting dhcp3-common_3.1.1-6+lenny4em1_armel.deb...
I: Extracting diff_2.8.1-12em1_armel.deb...
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I: Extracting gcc-4.3-base_4.3.2-1.1em1_armel.deb...
I: Extracting gnupg_1.4.9-3+lenny1em1_armel.deb...
I: Extracting gpgv_1.4.9-3+lenny1em1_armel.deb...
I: Extracting grep_2.5.3~dfsg-6em1_armel.deb...
I: Extracting grip-config_0.1.2em1_all.deb...
I: Extracting gzip_1.3.12-6+lenny1em1_armel.deb...
I: Extracting hostname_2.95em1_armel.deb...
I: Extracting ifupdown_0.6.8+nmu1em1_armel.deb...
 -> Processing conffiles for ifupdown
I: Extracting initscripts_2.86.ds1-61em1_armel.deb...
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I: Extracting libacl1_2.2.47-2em1_armel.deb...
I: Extracting libattr1_1%3a2.4.43-2em1_armel.deb...
I: Extracting libblkid1_1.41.3-1em1_armel.deb...
I: Extracting libbz2-1.0_1.0.5-1em1_armel.deb...
I: Extracting libc6_2.7-18lenny4em1_armel.deb...
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I: Extracting libcomerr2_1.41.3-1em1_armel.deb...
I: Extracting libdb4.6_4.6.21-11em1_armel.deb...
I: Extracting libdevmapper1.02.1_2%3a1.02.27-4em1_armel.deb...
I: Extracting libgcc1_1%3a4.3.2-1.1em1_armel.deb...
I: Extracting liblocale-gettext-perl_1.05-4em1_armel.deb...
I: Extracting libncurses5_5.7+20081213-1em1_armel.deb...
I: Extracting libncursesw5_5.7+20081213-1em1_armel.deb...
I: Extracting libnewt0.52_0.52.2-11.3+lenny1em1_armel.deb...
I: Extracting libpam-modules_1.0.1-5+lenny1em1_armel.deb...
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I: Extracting libpopt0_1.14-4em1_armel.deb...
I: Extracting libreadline5_5.2-3.1em1_armel.deb...
I: Extracting libselinux1_2.0.65-5em1_armel.deb...
I: Extracting libsepol1_2.0.30-2em1_armel.deb...
I: Extracting libslang2_2.1.3-3em1_armel.deb...
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I: Extracting libssl0.9.8_0.9.8g-15+lenny8em1_armel.deb...
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I: Extracting libusb-0.1-4_2%3a0.1.12-13em1_armel.deb...
I: Extracting libuuid1_1.41.3-1em1_armel.deb...
I: Extracting libvolume-id0_0.125-7+lenny3em1_armel.deb...
I: Extracting login_1%3a4.1.1-6+lenny1em1_armel.deb...
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I: Extracting mawk_1.3.3-11.1em1_armel.deb...
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I: Unpacking complete.
Get:1 http://www.emdebian.org lenny Release.gpg [197B]
Ign http://www.emdebian.org/grip/ lenny/main Translation-en_US
Get:2 http://www.emdebian.org lenny Release [21.4kB]
Ign http://www.emdebian.org lenny Release
Ign http://www.emdebian.org lenny/main Packages
Ign http://www.emdebian.org lenny/main Sources
Ign http://www.emdebian.org lenny/main Packages
Ign http://www.emdebian.org lenny/main Sources
Hit http://www.emdebian.org lenny/main Packages
Hit http://www.emdebian.org lenny/main Sources
Fetched 198B in 0s (2,020B/s)
Reading package lists... Done
W: GPG error: http://www.emdebian.org lenny Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY B5B7720097BB3B58

Multistrap system installed successfully in /home/mike/celf/multistrap/RFS/.

Let’s explain the parameters:

  • armel is the architecture, for our example: arm in little endian
  • -d $PWD/RFS is the output directory containing the root filesystem. Be careful to pass an absolute path.
  • -f multistrap.conf is the name of the configuration file

If you look at RFS/dev, you will see that there are no device files in it. This will be a problem at boot time, unless you build a kernel with the below options:

CONFIG_DEVTMPFS=y
CONFIG_DEVTMPFS_MOUNT=y

Thanks to these parameters, the kernel will automatically mount a tmpfs filesystem on /dev, and will populate it with devices present on the system.

Now we have a root filesystem, but we still need to run the package configuration scripts to make it usable. The packages were installed, but their configuration scripts couldn’t be executed, because they can only run on the target architecture.

The easiest way to do this is to use NFS. On the host side, you need to export the root filesystem directory through NFS. On the target side you have to select /bin/sh for the init process. A typical kernel command could be:

console=ttyS0,115200 root=/dev/nfs nfsroot=192.168.0.1:/path/RFS rw ip=192.168.0.20 init=/bin/sh

Then boot your board. You should reach a command line.

First mount /proc:

mount -t proc nodev /proc

Then configure your packages using this command line:

PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin  dpkg --configure -a

You will get a few questions about localization for tzdata, then the packages will be configured.

Finally go back to your host to change the RFS/etc/inittab file by uncommenting the below line and modifying it according to your serial console configuration (usually 115200). For example, replace

#T0:23:respawn:/sbin/getty -L ttyS0 9600 vt100

by

T0:23:respawn:/sbin/getty -L ttyS0 115200 vt100

As we built this root filesystem as a normal user we may have problems with some setuid programs, which need to be owned by the root user. So let’s change the ownership of some directories:

sudo chown root:root -R RFS/bin RFS/usr/bin RFS/sbin RFS/usr/sbin

The last trick is to delete the root password by modifying RFS/etc/passwd, by replacing

root:x:0:0:root:/root:/bin/bash

by

root::0:0:root:/root:/bin/bash

You can now reboot your system without the init=/bin/sh kernel parameter. We now have a ready to use embedded Linux root filesystem with the power of Debian.

Other things to fix and do:

  • Configure the /etc/resolv.conf file to be able to connect to the Internet.
  • Configure the gateway in the ip= kernel parameter (ip=client-ip:server-ip:gw-ip:netmask:hostname:device:autoconf). For example: 
    bootargs=console=ttyS0,115200n8 root=/dev/nfs ip=192.168.2.100::192.168.2.1:255.255.255.0:emdebian:eth0:off nfsroot=192.168.2.1:/home/mike/work/celf/
  • Install other packages such as mtd-utils and vim
  • Install kernel modules (either manually or through a kernel package)
  • Add a new user
  • Create a minimum /etc/fstab file

You now have a Debian system for which it is very easy to add new software, and which can be configured in a very familiar way. That’s great to make product prototypes, small, low-power and secure servers for home or office use, and in some cases, even real products.

Bootlin at the Embedded Linux Conference and Android Builders Summit

In just two weeks from now, the Embedded Linux Conference will start in San Francisco, followed by the Android Builders Summit, at the usual Hotel Kabuki location, where the conference is taking place for the third consecutive year.

Embedded Linux Conference 2011

The program of the Embedded Linux Conference has been announced recently, and as usual, features a wide set of technical embedded Linux talks:

  • Filesystem/storage: Power Fail Safe FAT File System, Optimizations For Cheap Flash Media, from Arnd Bergmann, who has also recently published a very interesting article on the same topic.
  • Power management: Faster Resume For More Energy Savings on MeeGo, Powerdebug(ging): A Linaro Perspective, How to Power Tune a Device Running on a Linux Kernel for Better Suspend Battery Life, The Evolution of Tracing and Profiling for Power Management and Accelerators, Runtime PM: Upstream I/O Device Power Management
  • Real-time: Solving Real-Time Scheduling Problems with RT_PREEMPT and Deadline-Based Scheduler, Real-time Audio on Embedded Devices, Identifying Embedded Real-Time Latency Issues: I-Cache and Locks
  • Build system, with a huge number of Yocto-related talks, but no other build systems represented: State of OpenEmbedded Internal Toolchain and SDKs, Yocto Project: Practical Kernel Development Tutorial, Building Custom Embedded Images with Yocto, The Yocto Project and its Application Development Toolkit (ADT) – The Answer to Effective Embedded Application Development, Yocto Project Community BoFs, Delivering Predictability: The Yocto Project Autobuilder, Automated Sanity Testing, License Collection, and Build Statistics Tracking
  • Multimedia: Fun with QML and JavaScript, Integrating a Hardware Video Codec into Android Stagefright using OpenMAX IL, Media Controller Framework (MCF) For OMAP2+ Display Subsystem, Video4linux: Progress, New videobuf2 Framework and the Media Controller, Bringing up HDMI Display for OMAP4 Panda Board – Design, Challenges and Lessons Learned, Linux Graphics Meets the ARM Ecosystem
  • FPGA: Dynamic Co-simulation of FPGA-based Linux Systems-on-Chip, A High Performance Interface Between the OMAP3 and an FPGA
  • Networking: What Embedded Linux Developers Should Know About IPv6, Zigbee Networking & Linux
  • Debugging: Kernel Shark Tutorial and Tools and Techniques for Debugging Embedded Systems
  • Optimization: Snapshot Booting on Embedded Linux, ARM Neon Instruction Set and Why You Should Care, Controlling Memory Footprint at All Layers: Linux Kernel, Applications, Libraries and Toolchain, High-Performance Computing using GPUs, What Are and How to Find a Program’s Unused DSOs
  • Low-level: Board Bringup: Open Source Hardware and Software Tools, Working with HardIRQs: Life Beyond Static IRQ Assignments, Genie in the Bottle: Linux Drivers for the AM1808 PRU
  • And many other talks on various topics: LLVM, Clang and Embedded Linux Systems, Linaro: A Year of Change, Control, Recover and Debug Your Embedded Product with PCD, Developer’s Diary: Helping the Process, High-Level Web Interface to Low-Level Linux I/O on the Beagleboard, Linaro Automated Validation on ARM, Crowd Sourcing and Protecting the Open Source Community, Android for Servers?, Hot Multi-OS Switch: How to run Ubuntu, ChromiumOS, Android at the Same Time on an Embedded Device.

This edition will be the first one organized since the merge between the CE Linux Forum into the Linux Foundation, and will therefore be a great opportunity to see if this merge had any impact on the technical quality of the conference.

My colleagues Maxime Ripard (who joined Bootlin just a week ago) and Gregory Clement as well as myself will be present at the Embedded Linux Conference and the Android Builders Summit, and we will as usual record all talks of both of these conferences and will put them online, as we have done recently for the talks that took place during the Embedded Linux Conference Europe 2010 in Cambridge. Do not hesitate to meet us in San Francisco!

ELC-E 2010 tutorial videos

Videos from the embedded Linux and Android tutorials at ELC-E 2010, by Chris Simmonds

As releasing ELC-E 2010 videos, here are recordings of the embedded Linux and Android tutorials, performed by Chris Simmonds on October 26, 2010.

Chris SimmondsVideo capture
2net
The Embedded Linux Quick Start Guide – Part 1
Slides
Video (52 minutes, 397M)
Chris SimmondsVideo capture
2net
The Embedded Linux Quick Start Guide – Part 2
Slides
Video (79 minutes, 660M)
Chris SimmondsVideo capture
2net
The Embedded Linux Quick Start Guide – Part 3
Slides
Video (67 minutes, 501M)
Chris SimmondsVideo capture
2net
What else can you do with Android? – Part 1
Slides
Video (49 minutes, 432M)
Chris SimmondsVideo capture
2net
What else can you do with Android? – Part 2
Slides
Video (31 minutes, 293M)
Chris SimmondsVideo capture
2net
What else can you do with Android? – Part 3
Slides
Video (59 minutes, 545M)

GStreamer 2010 conference videos

Videos from the 2010 edition of the GStreamer conference, Cambridge, UK, Oct. 26, 2010.

After releasing ELC-E videos, here are videos from the 2010 edition of the GStreamer conference. As usual, these videos are released under the terms of the Creative Commons Attribution – ShareAlike Licence version 3.0.

Jonas HolmbergVideo capture
Axis
Case study – GStreamer on Axis devices
Slides
Video (26 minutes):
full HD (223M), 450×800 (72M)

Sebastian DrögeVideo capture
Collabora Multimedia
WebM and GStreamer
Slides
Video (8 minutes):
full HD (75M), 450×800 (24M)

Florent ThieryVideo capture
UbiCast
Using gstreamer for building automated webcasting systems
Slides
Video (31 minutes):
full HD (361M), 450×800 (107M)

Zeeshan AliVideo capture
Nokia
Implementing DLNA using GStreamer
Slides
Video (29 minutes):
full HD (282M), 450×800 (88M)

Olivier CrêteVideo capture
Collabora
Integrating VideoConferencing into Everyday Applications
Slides
Video (29 minutes):
full HD (334M), 450×800 (103M)

Håvard GraffVideo capture
Tandberg
Case study – Tandberg and GStreamer
Video (61 minutes):
full HD (734M), 450×800 (212M)

Wim TaymansVideo capture
Collabora Multimedia
Keynote – GStreamer – Current and future development
Video (47 minutes):
full HD (310M), 450×800 (136M)

Rob ClarkVideo capture
Texas Instruments
GStreamer and OMAP4
Video (37 minutes):
full HD (336M), 450×800 (128M)

Martin BissonVideo capture
3D Stereoscopic and GStreamer
Video (13 minutes):
full HD (124M), 450×800 (39M)

Jan SchmidtVideo capture
Oracle Corporation
Interactivity in GStreamer pipelines
Slides
Video (20 minutes):
full HD (265M), 450×800 (76M)

Mike SmithVideo capture
Songbird
Cross platform development with GStreamer
Video (51 minutes):
full HD (542M), 450×800 (165M)

Emanuele QuacchioVideo capture
ST Microelectronics
A GStreamer based framework for adaptive streaming applications
Video (54 minutes):
full HD (592M), 450×800 (174M)

Josep TorraVideo capture
Fluendo
Intel SMD elements in GStreamer
Slides
Video (50 minutes):
full HD (371M), 450×800 (151M)

Philippe NormandVideo capture
Igalia
Webkit, HTML5 and GStreamer
Slides
Video (38 minutes):
full HD (229M), 450×800 (106M)

Edward HerveyVideo capture
Collabora Multimedia
Challenges of video editing in your pocket
Slides
Video (53 minutes):
full HD (416M), 450×800 (174M)

David SchleefVideo capture
Entropy Wave
Optimizing multimedia with Orc
Slides
Video (58 minutes):
full HD (493M), 450×800 (175M)

Luciana FujiiVideo capture
Holoscopio
Landell – live streaming for the masses
Slides
Video (21 minutes):
full HD (110M), 450×800 (58M)

Zaheer MeraliVideo capture
Flumotion and GStreamer
Video (35 minutes):
full HD (202M)

Andrey Nechypurenko and Maksym ParkachovVideo capture
Adaptive video streaming with Ice and GStreamer
Slides
Video (35 minutes):
full HD (279M), 450×800 (107M)

ELCE 2010 videos – Now in full HD

Videos from the Embedded Linux Conference Europe, Cambridge, UK, October 2010

Just a few weeks before the next edition of the Embedded Linux Conference in San Francisco, here are the videos from the previous edition in Europe a few months ago.

These videos took more time to process than expected, because of intense months on our side, but also because of the switch to the VP8 video codec. VP8 is the new Open Source and royalty free video codec, and is a successor to the codec that Theora was derived from. Unlike Theora which is now lagging behind, it is a very close competitor to H264, both in terms of quality and video size.

The switch to VP8 allowed us to release the videos in their original full HD resolution (we now have three full HD camcorders to shoot conference videos), with video files of about the same size.

You will probably need a recent GNU/Linux distribution (such as Ubuntu 10.10) to watch these videos. As this codec released by Google is taking off quickly, you should also find solutions to watch videos on Windows and MacOS X. Don’t hesitate to post comments here about your experience playing these files. You can even watch them on the Panda board, which can decode VP8 with its hardware video decoder.

As usual, these videos are released under the terms of the Creative Commons Attribution – ShareAlike Licence version 3.0.

As often in conferences, the videos were unfortunately shot is tough lighting conditions. The organizers usually turn off the lights to make it easier for the audience to read the screen. The consequence is a high contrast between the speaker and the screen, causing the speaker to appear very dark when we film her or him together with the screen. In a number of videos, we tried to solve this by using a beach mode provided by our camcorders. While the speaker now looks great, this unfortunately blurred the screen, causing more inconvenience than benefits. We gave up this mode in the last videos and will shoot ELC 2011 is the standard way, even if the speaker looks dark again. At least, with full HD videos, you will be able to read the slides directly on the screen.

The videos from the 2010 GStreamer conference will also be available in the next days, and to help you produce your own videos, we will release our new video processing scripts soon too.

Ruud DerwigVideo capture
Welcome speech
Video (15 minutes):
full HD (228M), 450×800 (71M)

Wolfram SangVideo capture
Pengutronix
Developer’s Diary: Supporting Maintainers
Slides
Video (46 minutes):
full HD (888M)
Rekha Kumar and Nipuna GunasekeraVideo capture
Texas Instruments
Panda board demonstration
Video (14 minutes):
full HD (373M), 450×800 (85M)

Robert SchusterVideo capture
OpenJDK
OpenJDK for Embedded Linux Devices
Slides
Video (39 minutes):
full HD (947M), 450×800 (225M)
Philippe RobinVideo capture
Linaro
Facilitating Open Source Development and Collaboration
Slides
Video (46 minutes):
full HD (548M), 450×800 (160M)
Tim BirdVideo capture
Sony
Android System Programming – Tips and Tricks
Slides
Video (40 minutes):
full HD (471M), 450×800 (142M)
Mischa Jonker and Ruud DerwigVideo capture
Synopsys
Portability is for People Who Cannot Write New Programs – GNU/Linux/OS on ARC
Slides
Video (34 minutes):
full HD (517M), 450×800 (148M)
Leif LindholmVideo capture
ARM
Software Considerations When Using High-Performance Memory Systems
Slides
Video (46 minutes):
full HD (511M), 450×800 (153M)
Ravi Sankar GunturVideo capture
Samsung
A Simple Method to Detect Memory Leaks and Buffer Overruns
Slides
Video (17 minutes):
full HD (171M), 450×800 (55M)
Will NewtonVideo capture
Imagination Technologies
Exploiting On-chip Memories in Embedded Linux Applications
Slides
Video (20 minutes):
full HD (255M), 450×800 (68M)
Andrey FedotovVideo capture
AFSoft
Linux Application in Safety-Critical Environment: A Real-Life Example
Video (39 minutes):
full HD (304M), 450×800 (111M)

Anna DushistovaVideo capture
Mentor Graphics
Eclipse and Embedded Linux Developers: What It Can and What It Cannot Do For You
Slides
Video (31 minutes):
full HD (338M), 450×800 (112M)
Yoshitake KobayashiVideo capture
Toshiba
Linux Kernel Acceleration for Long-term Testing
Slides
Video (30 minutes):
full HD (249M), 450×800 (89M)
Ralf BaechleVideo capture
Wind River
Embedded Linux – The State of the Nation
Video (40 minutes):
full HD (375M), 450×800 (128M)

Jim ZemlinVideo capture
Linux Foundation
The Linux Foundation and CELF
Video (21 minutes):
full HD (282M), 450×800 (71M)

Andrew MurrayVideo capture
MPC Data
The Right Approach to Minimal Boot Times
Slides
Video (41 minutes):
full HD (472M), 450×800 (149M)
Robert Schwebel and Sascha HauerVideo capture
Pengutronix
Barebox: Booting Linux Fast and Fancy
Slides
Video (45 minutes):
full HD (779M), 450×800 (192M)
Kevin HilmanVideo capture
Deep Root Systems
Runtime Power Management
Slides
Video (45 minutes):
full HD (780M), 450×800 (195M)
Michael OpdenackerVideo capture
Bootlin
Flash Filesystem Benchmarks
Slides
Video (47 minutes):
full HD (937M), 450×800 (229M)
Ari RauchVideo capture
Texas Instruments
The Dynamic Role of Open Linux Architectures in Today’s Mobile Landscape
Slides
Video (34 minutes):
full HD (789M), 450×800 (203M)
Benjamin GaignardVideo capture
ST-Ericsson
Android and GStreamer
Slides
Video (42 minutes):
full HD (432M), 450×800 (133M)
Hans VerkuilVideo capture
Tandberg
Supporting SoC Video Subsystems in Video4linux
Slides
Video (45 minutes):
full HD (424M), 450×800 (139M)
Benjamin ZoresVideo capture
Alcatel-Lucent
State of Multimedia in 2010’s Embedded Linux Devices
Slides
Video (45 minutes):
full HD (784M), 450×800 (219M)
Iago Toral QuirogaVideo capture
Igalia/Grilo
Grilo: Integrating Multimedia Content in Applications
Slides
Video (32 minutes):
full HD (515M), 450×800 (149M)
Jean-Paul SamanVideo capture
M2X BV
Porting VLC to TI DaVinci
Slides
Video (46 minutes):
full HD (516M), 450×800 (167M)
Stefan KostVideo capture
Nokia
Meego Multimedia
Slides
Video (37 minutes):
full HD (316M), 450×800 (105M)
Vitaly WoolVideo capture
Porting Legacy Code to Linux Userspace Driver Framework
Video (26 minutes):
full HD (400M), 450×800 (108M)

Martin MichlmayrVideo capture
Debian
Adapting Debian Installer to NAS and Other Consumer Devices
Slides
Video (21 minutes):
full HD (196M), 450×800 (62M)
Frank ScholzVideo capture
Android and Its Impact On Home Entertainment and Home Automation
Video (28 minutes):
full HD (347M), 450×800 (101M)

WookeyVideo capture
Yaffs
Yaffs updates
Slides
Video (27 minutes):
full HD (312M), 450×800 (95M)
Yann E. MorinVideo capture
Crosstool-ng
Crosstool-NG, A Cross-Toolchain Generator
Slides
Video (41 minutes):
full HD (1.1G), 450×800 (185M)
Armijn HemelVideo capture
Loohuis Consulting
Introducing the Binary Analysis Tool
Slides
Video (47 minutes):
full HD (507M), 450×800 (155M)
Kees-Jan DijkzeulVideo capture
Sioux Embedded Systems
A Gentle Introduction to Autotools
Slides
Video (41 minutes):
full HD (371M), 450×800 (124M)
Klaas Van GendVideo capture
Montavista
Deflating the Virtualization Hype in 3 Simple Steps
Slides
Video (38 minutes):
full HD (507M), 450×800 (131M)
Peter KorsgaardVideo capture
Buildroot
Do More With Less – On Driver-less Interfacing with Embedded Devices
Slides
Video (48 minutes):
full HD (529M), 450×800 (173M)
Ray KinsellaVideo capture
Intel
Xen in Embedded Systems
Slides
Video (34 minutes):
full HD (380M), 450×800 (135M)
Arnout VandecappelleVideo capture
Mind
Practical Testing of Open Source Embedded Systems
Slides
Video (51 minutes):
full HD (364M), 450×800 (160M)
Carmelo Amoroso and Rosario ContarinoVideo capture
STMicroelectronics
Lightweight Prelinker for Kernel Modules
Slides
Video (45 minutes):
full HD (302M), 450×800 (129M)
Frank RowandVideo capture
Sony
Identifying Embedded Real-Time Latency Issues: I-Cache and Locks
Slides
Video (43 minutes):
full HD (272M), 450×800 (120M)
David AndersVideo capture
Texas Instruments
Board Bringup: Methods and Utilities
Slides
Video (34 minutes):
full HD (248M), 450×800 (99M)
John OgnessVideo capture
Linutronix
IPL+UBI: Flexible and Reliable with Linux as the Bootloader
Slides
Video (27 minutes):
full HD (232M), 450×800 (89M)
Vitaly WoolVideo capture
WLAN Chips in Embedded Linux Systems
Video (23 minutes):
full HD (264M), 450×800 (82M)

Grant LikelyVideo capture
Secret Lab Technologies
ARM Flattened Device Tree Status Report
Slides
Video (40 minutes):
full HD (542M), 450×800 (173M)
Koen KooiVideo capture
OpenEmbedded
The State of OpenEmbedded and Tooling to Make Life Easier
Slides
Video (44 minutes):
full HD (308M), 450×800 (122M)
Harald WelteVideo capture
OpenBSC
Running your own GSM+GPRS network using OpenBSC, OsmoSGSN and OpenGGSN
Slides
Video (49 minutes):
full HD (402M), 450×800 (163M)
Arun RaghavanVideo capture
Collabora
PulseAudio In The Embedded World
Slides
Video (30 minutes):
full HD (204M), 450×800 (88M)
Jake EdgeVideo capture
LWN.net
Understanding Threat Models for Embedded Devices
Slides
Video (29 minutes):
full HD (186M), 450×800 (80M)
Gustavo F. PadovanVideo capture
Profusion
The Linux Bluetooth Stack
Slides
Video (30 minutes):
full HD (213M), 450×800 (87M)
Klaas van GendVideo capture
Closing session
Video (62 minutes):
full HD (1.2G), 450×800 (285M)

Chris SimmondsVideo capture
2net
The Embedded Linux Quick Start Guide – Part 1
Slides
Video (52 minutes):
full HD (397M)
Chris SimmondsVideo capture
2net
The Embedded Linux Quick Start Guide – Part 2
Slides
Video (79 minutes):
full HD (660M)
Chris SimmondsVideo capture
2net
The Embedded Linux Quick Start Guide – Part 3
Slides
Video (67 minutes):
full HD (501M)
Chris SimmondsVideo capture
2net
What else can you do with Android? – Part 1
Slides
Video (49 minutes):
full HD (432M), 450×800 (144M)
Chris SimmondsVideo capture
2net
What else can you do with Android? – Part 2
Slides
Video (31 minutes):
full HD (293M), 450×800 (94M)
Chris SimmondsVideo capture
2net
What else can you do with Android? – Part 3
Slides
Video (59 minutes):
full HD (545M), 450×800 (180M)

Here are also videos of the Embedded Linux and Android tutorials by Chris Simmonds.

Barebox 2011.03 released, with contributions from Bootlin

BareboxBarebox is a bootloader started about two years ago for embedded systems of various architectures. It plays the same role as U-Boot, which is the best known project in this area, but has several advantages over U-Boot. First, it has a much better configuration and compilation system, based on the one used by the Linux kernel: instead of the rusty include/configs/myboard.h configuration headers in U-Boot, Barebox provides a nice menuconfig/xconfig/defconfig based configuration system, that everyone is familiar with. Second, Barebox has a source code organization very similar to the one of the Linux kernel and has replicated the device/driver model of the kernel. This allows to have a nice separation between device drivers and their instantiation, and a source code that looks familiar to anyone that already does kernel development.

Of course, as Barebox is newer than U-Boot, the number of architectures and platforms is more limited, but it is growing rapidly. It already supports ARM, PPC, Blackfin, x86 and a testing sandbox architecture. On ARM, the supported platforms are AT91, EP93xx, iMX, Nomadik, OMAP, S3C24xx and Versatile. On PPC, a single mpc5xxx platform is supported. Patches to add support for the NIOS architecture have also been posted recently (NIOS is a soft-core architecture from Altera).

As a young but fast-growing project, Barebox has chosen a quick development cycle: new releases are made each month, and Barebox 2011.03 has been released a few days ago. It has many ARM and generic improvements, but is also the first release with contributions from Bootlin :

Gregory CLEMENT (3):
      BMP: Add support for 32bpp video frame buffer
      ARM STM/i.MX: Add possibility to choose the bit per pixel for STM video driver
      fb i.MX23/28: Add the reset control of LCD

My colleague Gregory Clement has contributed several improvements to framebuffer support on the i.MX platform. Those improvements were made in the context of a customer project, for which Barebox was used as a way of showing immediately after the device start-up a nice logo on the screen, while the system continues to boot in the background. Initially, the user had to wait 20+ seconds to see a logo on the screen showing that the system was booting. With our Barebox based solution, a logo is now visible on the screen less than 2 seconds after the power on button is pushed.