Contributions to Barebox: initial Marvell SoC support

Barebox is a bootloader that strives to be a modern alternative to U-Boot. It currently supports ARM, Blackfin, MIPS, NIOS2, OpenRISC, PowerPC and x86 as CPU architectures, and while it doesn’t have as much hardware support as U-Boot yet, it does have a number of very significant advantages over U-Boot: a proper device model very similar to the one used in the Linux kernel, which makes the code very clean and nice, and a configuration system that uses kconfig, like the Linux kernel, which is a lot better than the per-board header files used by U-Boot with lots of cryptic macros.

Bootlin had already contributed to Barebox in the past, as our engineer Maxime Ripard added the support for the Crystalfontz i.MX28 boards.

More recently, we contributed basic support for the Marvell Kirkwood, Marvell Armada 370 and Marvell Armada XP ARM processors. This work was released as part of the 2013.07.0 release. For now, the support is fairly minimal, as it only allows to boot a Barebox bootloader that has serial port support. The most important part of the work was to write a kwbimage tool (see kwbimage.c), which allows to generate bootable images for Marvell processors. Our work contained minimal support for the Armada XP-based OpenBlocks AX3 board, the Armada XP-based GP development board, the Armada 370-based Mirabox from Globalscale and the Kirkwood-based Guruplug from Globalscale. Our work was quickly extended by Sebastian Hesselbarth, who added basic support for the Marvell Dove processor, and the Cubox platform from SolidRun, which uses the Dove processor.

Of course, such support is far from being complete, we are hoping in the future to add support for network, NAND and SD, in order to make Barebox really useful and usable on Marvell platforms.

The details of our contributions are:

Bootlin contributions to the 3.10 kernel

The 3.10 Linux kernel has been released a few days ago. According to LWN, with almost 13.500 non-merge commits, the 3.10 has been the busiest ever, and also the fastest. Bootlin engineers again contributed to this release, with 99 patches integrated, making Bootlin the 28th most active company contributing, right between ST-Ericsson (103 patches) and ARM (97 patches). See http://www.remword.com/kps_result/3.10_whole.html for the complete statistics.

This time, Bootlin contributions include:

  • LPAE support for the Marvell Armada XP SoC, done by Grégory Clement.
  • Fix for errata 4742 of the PJ4B CPU core (used in Armada 370/XP), which prevented booting Armada 370 platforms after ARM optimized some TLB operations. Done by Grégory Clement.
  • Support for NOR flash on Marvell Armada 370 and Armada XP SoC, done by Ezequiel Garcia
  • Addition of a mvebu-mbus driver to handle the address decoding mechanism and configurable memory windows of Marvell SoC. The mach-kirkwood, mach-orion5x, mach-dove, mach-mv78xx0 and mach-mvebu Marvell platforms are all converted to use it. Developping this driver was a requirement to enable PCIe in a Device Tree compatible way on these platforms. Done by Thomas Petazzoni.
  • Addition of Device Tree information for the PCIe controllers of the Armada 370 and Armada XP, but unfortunately not the PCIe driver itself (which will arrive in 3.11). Done by Thomas Petazzoni.
  • Support for the thermal sensor on Marvell Armada 370 and Armada XP SoC, done by Ezequiel Garcia
  • A lot of reorganization of the Device Tree compatible strings for the Allwinner ARM SoC support, to prepare for the addition of additional SoCs in the future. Done by Maxime Ripard.
  • Improvements to the Allwinner pinctrl driver, with support for the A10 and A13 SoC. Done by Maxime Ripard.
  • Enabling of the I2C GPIO expander of the Armada 370 based Mirabox platform. Done by Grégory Clement.
  • A few updates to the support for the i.MX28 Crystalfontz boards: touchscreen and one-wire support on CFA10049. Done by Alexandre Belloni.
  • Various cleanups and improvements to the OMAP GMPC driver, done by Ezequiel Garcia.
  • Various cleanups and improvements to the Marvell Armada 370/XP IRQ controller driver, done by Thomas Petazzoni.

In detail, the contributions are:

Workshop on the Altera SoC FPGA platform

On June 25, 2013, Altera and some partner companies where organizing a workshop in Toulouse (where some of the Bootlin offices are located) about the Altera SoC FPGA platform. For $99, I participated to this full-day workshop, with a small training of the hardware and software tools available for this platform, and went away with a the development kit that was used for the practical labs, the Arrow SoCKit evaluation board.

sockit-1

The Altera SoC FPGA platform is a single chip that combines a dual Cortex-A9 processor and a Cyclone V FPGA (other variants are available, such as single core ARM, or bigger FPGAs). Since both are integrated on the same chip, it removes the need for a complex bus between the application processor and a separate FPGA, and it provides a very high bandwidth between the processor and the FPGA to exchange data. As can be seen on the following diagram, the Arrow SocKit evaluation board has a good number of peripherals, some of them connected to the HPS side of the processor (HPS stands for Hard Processor System, which is dual Cortex-A9 and all the hard peripherals), and some others connected to the FPGA side of the processor. Specifically, the workshop was centered around playing with the LEDs and the buttons connected to the FPGA side.

Block diagram of the SoCKit evaluation board
Block diagram of the SoCKit evaluation board

The morning of the workshop was dedicated to the hardware part, using two tools: Qsys (Altera’s System Integration Tool) and Quartus II (FPGA design). The Qsys tool allows to graphically build the hardware architecture of the SoC FPGA: you can bring the Hard Processor System, and then some additional FPGA IPs and connect them together. In the examples, two PIO IPs were added to the FPGA side, one to control LEDs and the other to control buttons. All the pin muxing and the DRAM configuration also takes place in Qsys, which in the end will automatically generate numerous elements:

  • FPGA code to be used by Quartus (for the FPGA side)
  • pre-loader source code (actually modifications to U-Boot to take into account the pin muxing and the DRAM configuration)
  • a Device Tree for the Linux kernel (that takes into account all the peripherals enabled in the system configuration)
  • etc.
Qsys allows to design the overall architecture of the SoC FPGA components, including all the FPGA IPs. On this picture, we see the two PIO IPs used to control LEDs and buttons.
Qsys also to design the overall architecture of the SoC FPGA components, including all the FPGA IPs. On this picture, we see the two PIO IPs used to control LEDs and buttons.

Once this system-level configuration is done with Qsys, Quartus is used to synthesize the FPGA side. Finally, the FPGA bitstream can be loaded into the FPGA, and using a JTAG connection and a System Console tool, one can directly read/write the registers of the FPGA IPs that have been integrated, and easily test them without having any software running. With the SOCKit evaluation board, the JTAG connection takes place through a USB to micro-USB cable, so no special hardware is needed.

The afternoon of the workshop was dedicated to the software part, obviously mostly centered on U-Boot and Linux. The pre-loader source code (actually the U-Boot SPL) is generated by the Qsys tool to take into account all the details of the system configuration, so after doing a build of U-Boot, the labs explained how to push the U-Boot binary to the board using the JTAG connection, under the DS-5 development environment (which is the development environment provided by ARM, based on Eclipse, with a special integration of Altera tools). The lab showed that you can set breakpoints, and do step by step execution of U-Boot, as one would expect. One nice thing is that the “Peripheral Registers” view in DS-5 is automatically updated according to the hardware components in the system: all the registers of the FPGA IPs we had integrated were immediately visible, and one was able to play with the LEDs and buttons directly from DS-5 through the JTAG connection. The remainder of the labs were dedicated to booting a pre-built Linux kernel, using a Device Tree generated by Qsys previously and loaded by U-Boot. Once Linux was booted, the labs were demonstrating how to play with the LEDs using /sys/class/leds/.

Registers of FPGA IPs are automatically visible in DS5
Registers of FPGA IPs are automatically visible in DS5

All in all, it was a great workshop, giving a good overview of the tools they offer and the capabilities of such platforms, I definitely recommend others to look for the other dates of this workshop and attend, it was well worth the price (dates in US, dates in Europe). I also appreciated that the amount of marketing/commercial was really reduced to the minimum. After the lunch break, there was an additional presentation by a person from Linear Technology about the power supply architecture of two boards based on this SoC FPGA processor, and it was very technical and highly informative.

As an embedded Linux developer, I’ve however found the tools to be too much based on graphical interfaces, with millions of windows and buttons to fill in, and a sensation of not really controlling which tool was doing what exactly. For example, it is a bit unclear at first which files are really your “source” files and which other files are generated. Having graphical interfaces also makes me wonder how all the build steps can be automated. It seems like version control and automated builds are not necessarily taken into account when designing those tools, but more investigation is certainly needed to get a good understanding of what those tools are doing.

On the Linux kernel side, it is worth noting that Altera has engaged into an upstreaming process for this architecture, and one can find some mainline support for this platform in arch/arm/mach-socfpga in the kernel tree. It is worth mentioning that Xilinx also has a similar architecture combining a dual Cortex-A9 and FPGA, called Zynq, which has mainline kernel support in arch/arm/mach-zynq.

And below, the front and bottom of the SoC Kit evaluation board:

SoC Kit evaluation board back side

SoC Kit evaluation board front side

GSoC: Buildroot gaining improved ARM multimedia support

Google Summer of Code 2013 logo

The Buildroot project is participating for the first time to the famous Google Summer of Code. This program, operated by Google, allows open-source projects to have students working on specific tasks for the summer, and the students get paid for their work, get mentored by open-source developers, learn about software development, open-source communities and more.

For its first participation to the GSoC, the Buildroot community has chosen one project: improving support for multimedia features of popular ARM SoCs. This consists in packaging in Buildroot all the necessary libraries and software components to support OpenGL, OpenVG, EGL, OpenMAX and similar technologies for the major ARM processors. The selected student for this project is Spenser Gilliland and Bootlin engineer Thomas Petazzoni is mentoring Spenser for this project.

The focus of the project is to add support for the multimedia features of the OMAP3, OMAP4 and AM33xx processors from Texas Instruments, the Broadcom processor found on the RasberryPi, the i.MX6 processor from Freescale, the Exynos 4 from Samsung and the Allwinner A1x processors. Throughout the next three months, support for the multimedia capabilities of those processors in Buildroot should become easier to use.

Spenser has already contributed support for GStreamer 1.x in Buildroot (which required upgrading the entire GLib/Gtk/Webkit stack) and OpenMAX support for the RasberryPi, and he is currently working on OpenGL support for the OMAP3/OMAP4/AM33xx platforms. The initial part of Spenser’s work will be in the next 2013.08 Buildroot release, while the remainder will have to wait the 2013.11 release.

For more details about the project, see its description on the eLinux.org wiki, and you can also keep track of Spenser’s progress.

Buildroot 2013.05 released, Bootlin contributions inside!

Buildroot logoAs planned by the release schedule, the Buildroot 2013.05 version landed at the end of May. Peter Korsgaard, the project’s maintainer, highlighted the most important additions in his release email. With more than 900 commits, it has been the busiest ever development cycle, showing that the Buildroot project is more and more active.

With 175 commits in this release, Bootlin has again participated significantly to the development of Buildroot:

   217  Gustavo Zacarias
   167  Thomas Petazzoni (Bootlin)
   109  Will Wagner
    86  Peter Korsgaard
    44  Simon Dawson
    27  Yann E. MORIN
    25  gilles.talis@gmail.com
[...]
     6  Maxime Ripard (Bootlin)
[...]
     1  Alexandre Belloni (Bootlin)
     1  Ezequiel Garcia (Bootlin)
[...]

Amongst the features and improvements contributed by Bootlin:

  • Support for the next generation Wayland display server has been added. For now, only Wayland over the framebuffer is supported, but additional improvements are expected to come in the future.
  • Integration of packages to build all the Qt5 components: qt5base, qt5declarative, qt5graphicaleffects, qt5imageformats, qt5jsbackends, qt5multimedia, qt5quick1, qt5script, qt5svg, qt5webkit and qt5xmlpatterns.
  • A mechanism of virtual packages to expose the OpenGL, OpenVG and EGL implementations has been put in place, with for now the RasberryPi providing such implementations. Those virtual packages are for example used in the Qt5 packages mentionned above, for those that require OpenGL.
  • A cleanup of Buildroot core dependencies: flex and bison are no longer mandatory to use Buildroot, they are automatically built when needed. This apparently simple move required a number of fixes and updated to a significant number of packages.
  • Many external toolchains were updated, especially the Linaro toolchains.
  • The build process of gdb was converted to the package infrastructure, instead of being a hand-written Makefile. This is part of an effort to progressively convert the toolchain building process to the package infrastructure.
  • A default configuration was added for the Atmel AT91SAM9G45M10-EK evaluation board, which allows Buildroot users to easily build a minimal working system for this platform.
  • A number of build issues were fixed by Maxime Ripard, thanks to the daily automated builds done by the Bootlin Jenkins system that Maxime has set up.
  • A huge number of build issues trigerred by the autobuilders have also been fixed thanks to Bootlin engineers contributions.

In addition to this, Thomas Petazzoni has done some major improvements to the automated build system that the Buildroot project uses, which he detailed in an e-mail sent to the project mailing list. These improvements make the autobuilder infrastructure more scalable, and allows to provide statistics, and a much better daily report sent to the project’s mailing list.

In detail, the contributions of Bootlin were:

Bootlin contributions to the 3.9 kernel

A few months ago, we published a blog post showing our contributions to the 3.8 Linux kernel. With 128 commits merged in 3.8, Bootlin was ranked as the 17th company in terms of kernel contributions.

The 3.9 kernel has been released a few weeks ago, with again a significant number of contributions from Bootlin. According to these statistics, Bootlin contributed 92 patches during the 3.9 cycle, making the company the 26th most important contributor to the Linux kernel for this release, and this time, five engineers from Bootlin contributed patches.

Among the contributions that we made:

  • Added a basic infrastructure for irqchip drivers in the drivers/irqchip directory. This directory is now used to store the drivers for the IRQ controllers of various processors.
  • Made a number of improvements to the Marvell SDIO driver, including the addition of a Device Tree binding for it, and enabled its usage on Marvell Armada 370 and Armada XP platforms, as well as converting the Marvell Kirkwood platforms to use Device Tree probing instead of legacy probing for their SDIO interface.
  • Contributed a number of improvements to support Crystalfontz i.MX28 based modules, including the Device Tree for the CFA10037 expansion board, various improvements for the CFA10049 expansion boards, and a driver for the Himax HX8357B LCD controller.
  • A large number of improvements to the support of the Allwinner ARM SoCs, most notably a pinctrl driver for those SoCs, which allows to configure the muxing of I/O pins, and a gpio driver, to use the pins as general-purpose I/Os. We also contributed the support for the Miniand Hackberry platform, based on an Allwinner SoC. This work is all done by our engineer Maxime Ripard, who is the maintainer of the Allwinner SoC support in the Linux kernel.
  • Improvements to the PCA953x driver (for I2C GPIO expanders) in order to support the PCA9505 chip, that has 40 GPIOs. This required quite some work, as the PCA953x was originally limited to chips having at most 32 GPIOs. This improvement was done in order to support the GPIO expander box provided by Globalscale for the Armada 370-based Mirabox platform.
  • We added support for the Real Time Clock on Armada 370 and Armada XP based platforms, added support for local timers on Armada XP, added support for the new Armada XP GP evaluation board.
  • We enabled support for the SPI controllers and the USB controllers on Armada 370 and Armada XP based platforms.

Our high rate of contributions is going to continue, as we already have 95 patches merged for the upcoming 3.10 kernel and have already submitted a number of patches for the 3.11 kernel.

Here are details about our contributions to the 3.9 kernel:

Linux kernel 3.8 released, Bootlin top #17 contributor

Thomas Petazzoni and Grégory Clement, Bootlin kernel engineers
Thomas Petazzoni (front) and Grégory Clement (back) at the Embedded Linux Conference 2013 in San Francisco, discussing ARM Linux kernel issues.
Early last week, version 3.8 of the Linux kernel has been released by Linus Torvalds. The KernelNewbies web site, has, as usual, a great summary of what’s new in this release, together with lots of links to the relevant LWN articles. With 12394 commits, 3.8 has been the busiest ever kernel release cycle, the previous record being held by 2.6.25 with 12243 commits.

Despite this huge activity, Bootlin has been the 17th most active employer during the 3.8 cycle, with 128 commits merged into the mainline Linux kernel, representing a bit more than 1% of the total number of commits. See the statistics by employer at http://www.remword.com/kps_result/3.8_whole.html and in the traditional LWN article. This puts Bootlin before Nvidia, Qualcomm, ARM or Oracle in number of commits, and just a few commits behind Freescale. See the Git repository for the list of our contributions.

In detail, Bootlin contributions for 3.8 have been:

  • A large number of contributions related to the support of the Marvell Armada 370 and Armada XP SoCs, done by Grégory Clement and Thomas Petazzoni. Contributions included: a new network driver for the Armada 370 and Armada XP, support for the Armada XP-based OpenBlocks AX3 platform, support for the Armada 370-based Globalscale Mirabox platform, a big number of improvements and Device Tree support for the Marvell XOR engine driver, beginning of Device Tree support for the older Marvell Orion5x SoC family, support for the L2 cache found in Armada 370/XP, clock drivers for Armada 370/XP, SMP support for Armada XP, enabling of SATA on Armada 370/XP platforms.
  • The contribution of the initial support for a new SoC family in the mainline Linux kernel: the Allwinner A10 and Allwinner A13 ARM SoCs. This support has been contributed by Maxime Ripard, who has become the maintainer for this new ARM sub-architecture.
  • A driver for the I2C-based SSD1304 OLED display, a nice 128×32 pixels monochrome OLED display, contributed by Maxime Ripard.
  • A number of improvements in the support for the Crystalfontz i.MX28-based platforms, the CFA10036 and its expansion board the CFA10049. These contributions have also been made by Maxime Ripard.

Through these contributions, Bootlin have gained a good expertise in support for ARM SoCs and boards inside the Linux kernel. If you are interested in having us help you bring the support of your ARM board or ARM SoC into the mainline Linux kernel, do not hesitate to contact us, you will be directly answered by our engineers doing Linux kernel development!

Videos of the Embedded Linux Conference Europe 2012

With the approaching Embedded Linux Conference, to be held February 20-22 in San Francisco, we felt that it was time to finally fight with ffmpeg/libav and get the videos we had taken from the last Embedded Linux Conference Europe talks, encode them and publish them online. So here they are, as what we could consider a late Christmas gift.

There are so many talks that it might be hard to watch everything. So I’d like to share with you my preferred talks from this last ELCE (of course, I haven’t been able to see all talks, but only a third of them, so the following selection is only taken from the talks I have seen) :

  • For sure, the talk I have preferred is the Understanding PREEMPT_RT (The Real-Time Patch) talk from Steven Rostedt (Redhat). In an hour, Steven explained some very interesting internals of PREEMPT_RT, in a very clear way. Definitely a must see, in my opinion.
  • I also enjoyed the ARC Linux: From a Tumbling Toddler to a Graduating Teen talk from Vineet Gupta (Synopsys). While talking about a specific new CPU architecture that probably most of us have never used, Vineet is able to tell a very nice story by bringing you through various issues they had while porting Linux on this new CPU architecture, giving interesting and funny technical details in the process.
  • The talk about Regmap: The Power of Subsystems and Abstractions from Mark Brown (Wolfson Microelectronics) was also very good, in that it clearly explained the need for this new kernel subsystem, how the API works, etc. Definitely the kind of talk I’d like to see about more kernel subsystems: in an hour, you learn the philosophy of the subsystem, why it’s there, how it has been designed to solve the original problems, and the basics of its APIs. It’s often what’s missing from an API documentation: the philosophy behind it. Hour long talks that are capable of conveying this philosophy are therefore highly useful.
  • As usual, David Anders talk, this time about Board bringup: you, me and I2C has been very nice as well. It is a good introduction about electronics related to I2C, it doesn’t go very far for anyone having an existing experience of I2C, but is indeed a very good introduction for those who don’t. I really enjoyed the good explanation about pull-up resistors.
  • Finally, another talk that was great is Samuel Ortiz (Intel) talk about Near Field Communication with Linux. A bit like the Regmap talk, the great benefit of Samuel talk is that in an hour, he went through the different hardware available for NFC in Linux, the architecture of the software stack, the different software components that exist, their strenghts and weaknesses and so on. So without any prior knowledge about NFC, you get at the end of the talk a very good coverage of how this technology is supported by Linux today.

Well, enough with my suggestions, here is the complete list of videos:

Matt RanostayVideo capture
Beaglebone: The Perfect Telemetry Platform?
Slides
Video (24 minutes):
full HD (153M), 800×450 (74M)

Jim HuangVideo capture
0xlab
Implement Checkpointing for Android
Slides
Video (43 minutes):
full HD (291M), 800×450 (168M)

Wolfram SangVideo capture
Pengutronix e.K.
Maintainer’s Diary: Devicetree and Its Stumbling Blocks
Slides
Video (49 minutes):
full HD (329M), 800×450 (160M)

Matthias BruggerVideo capture
ISEE 2007 S.L.
A War Story: Porting Android 4.0 to a Custom Board
Slides
Video (34 minutes):
full HD (230M), 800×450 (106M)

Kishon Vijay AbrahamVideo capture
Texas Instruments
USB Debugging and Profiling Techniques
Slides
Video (40 minutes):
full HD (245M), 800×450 (109M)

Alan OttVideo capture
Signal 11 Software
Wireless Networking with IEEE 802.15.4 and 6LoWPAN
Slides
Video (52 minutes):
full HD (339M), 800×450 (156M)

João Paulo Rechi VitaVideo capture
INdT
Bluetooth Smart devices and Low Energy support on Linux
Slides
Video (36 minutes):
full HD (250M), 800×450 (116M)

Peter StugeVideo capture
OpenOCD: Hardware Debugging and More
Video (47 minutes):
full HD (316M), 800×450 (155M)

Alessandro RubiniVideo capture
PF_ZIO: Using Network Frames to Convey I/O Data and Meta-Data
Slides
Video (48 minutes):
full HD (317M), 800×450 (141M)

Joo-Young HwangVideo capture
Samsung
A New File System Designed for Flash Storage in Mobile
Slides
Video (54 minutes):
full HD (369M), 800×450 (152M)

Alexandre BelloniVideo capture
Adeneo Embedded
Boot Time Optimizations
Slides
Video (39 minutes):
full HD (261M), 800×450 (129M)

Philipp ZabelVideo capture
Pengutronix e.K.
Modular Graphics on Embedded ARM
Slides
Video (32 minutes):
full HD (217M), 800×450 (100M)

Karim YaghmourVideo capture
Opersys
Inside Android’s User Interface
Slides
Video (42 minutes):
full HD (284M), 800×450 (117M)

Samuel OrtizVideo capture
Intel
Near Field Communication with Linux
Slides
Video (35 minutes):
full HD (232M), 800×450 (92M)

Arnout VandecappelleVideo capture
Essensium/Mind
Upgrading Without Bricking
Slides
Video (56 minutes):
full HD (373M), 800×450 (172M)

Tim BirdVideo capture
Sony Network Entertainment
BoFs: Developer Tools and Methods: Tips & Tricks
Slides
Video (62 minutes):
full HD (395M), 800×450 (160M)

Matt LockeVideo capture
Texas Instruments
Are We Headed for a Complexity Apocalypse in Embedded SoCs?
Video (27 minutes):
full HD (167M), 800×450 (76M)

Sascha HauerVideo capture
Pengutronix e.K.
Barebox Bootloader
Slides
Video (47 minutes):
full HD (313M), 800×450 (134M)

Benjamin ZoresVideo capture
Alcatel-Lucent
Dive Into Android Networking: Adding Ethernet Connectivity
Slides
Video (46 minutes):
full HD (270M), 800×450 (118M)

Jiyoun ParkVideo capture
Samsung
Experiences as an OEM with Development of UI Frameworks
Video (42 minutes):
full HD (282M), 800×450 (158M)

Keshava MunegowdaVideo capture
Texas Instruments
FFSB and IOzone: File system Benchmarking Tools, Features and Internals
Slides
Video (56 minutes):
full HD (367M), 800×450 (171M)

Chris SimmondsVideo capture
2net Limited
The End of Embedded Linux (As We Know It)
Slides
Video (47 minutes):
full HD (324M), 800×450 (150M)

Steven RostedtVideo capture
Red Hat
Understanding PREEMPT_RT (The Real-Time Patch)
Slides
Video (61 minutes):
full HD (412M), 800×450 (186M)

Klaas van GendVideo capture
Vector Fabrics
Application Parallelization for Multi-Core Android Devices
Slides
Video (44 minutes):
full HD (293M), 800×450 (124M)

David AndersVideo capture
Texas Instruments
Board Bringup: You, Me, and I2C
Slides
Video (38 minutes):
full HD (217M), 800×450 (97M)

Rama PallalaVideo capture
Intel
Linux Power Supply Charging Subsystem
Video (35 minutes):
full HD (213M), 800×450 (83M)

Agusti FontquerniVideo capture
ISEE 2007 S.L.
Embedded Linux RADAR Device
Slides
Video (50 minutes):
full HD (331M), 800×450 (140M)

Matt PorterVideo capture
Texas Instruments
What’s Old Is New: A 6502-based Remote Processor
Slides
Video (58 minutes):
full HD (389M), 800×450 (181M)

Thomas PetazzoniVideo capture
Bootlin
Your New ARM SoC Linux Support Check-List
Slides
Video (56 minutes):
full HD (362M), 800×450 (150M)

Tracey M. Erway and Nithya A. RuffVideo capture
Intel and Synopsys
Can You Market an Open Source Project?
Slides
Video (43 minutes):
full HD (272M), 800×450 (103M)

Lars KnollVideo capture
Qt Project
Qt on Embedded Systems
Video (50 minutes):
full HD (337M), 800×450 (175M)

Koen KooiVideo capture
Circuitco
Supporting 200 Different Expansionboards: The Broken Promise of Devicetree
Slides
Video (37 minutes):
full HD (232M), 800×450 (102M)

Anna DushistovaVideo capture
Eclipse and Embedded Linux Developers: What it Can and Cannot Do For You
Slides
Video (58 minutes):
full HD (378M), 800×450 (167M)

Dave StewartVideo capture
Intel
Yocto Project Overview and Update
Video (52 minutes):
full HD (338M), 800×450 (139M)

Vineet GuptaVideo capture
Synopsys
ARC Linux: From a Tumbling Toddler to a Graduating Teen
Slides
Video (44 minutes):
full HD (269M), 800×450 (113M)

Laurent PinchartVideo capture
Ideas on Board
DRM/KMS, FB and V4L2: How to Select a Graphics and Video API
Slides
Video (48 minutes):
full HD (328M), 800×450 (145M)

Frank RowandVideo capture
Sony Network Entertainment
Practical Data Visualization
Slides
Video (46 minutes):
full HD (308M), 800×450 (141M)

Marcin JuszkiewiczVideo capture
Linaro
ARM 64-Bit Bootstrapping with OpenEmbedded
Slides
Video (32 minutes):
full HD (208M), 800×450 (88M)

Wim DecroixVideo capture
TPVision
Practical Experiences With Software Crash Analysis in TV
Slides
Video (35 minutes):
full HD (224M), 800×450 (87M)

Mark BrownVideo capture
Wolfson Microelectronics
Regmap: The Power of Subsystems and Abstractions
Video (44 minutes):
full HD (282M), 800×450 (124M)

Hans VerkuilVideo capture
Cisco Systems
Video4Linux: Current Status and Future Work
Slides
Video (33 minutes):
full HD (217M), 800×450 (100M)

Holger BehrensVideo capture
Wind River
Yocto Layer for In-Vehicle Infotainment
Slides
Video (43 minutes):
full HD (284M), 800×450 (123M)

Tero KristoVideo capture
Texas Instruments
Debugging Embedded Linux (Kernel) Power Management
Slides
Video (36 minutes):
full HD (241M), 800×450 (108M)

Martin BisVideo capture
BIS
Real-Time Linux in Industrial Appliances
Slides
Video (48 minutes):
full HD (323M), 800×450 (145M)

Jens GeorgVideo capture
Openismus GmbH
Rygel: Open Source DLNA, ready for Customer Products?
Slides
Video (33 minutes):
full HD (215M), 800×450 (88M)

Yoshitake KobayashiVideo capture
Toshiba
Improvement of Scheduling Granularity for Deadline Scheduler
Slides
Video (31 minutes):
full HD (195M), 800×450 (82M)

Tsugikazu ShibataVideo capture
NEC
LTSI (Long-Term Stable Initiative) Status Update
Slides
Video (44 minutes):
full HD (278M), 800×450 (111M)

Thomas GleixnerVideo capture
Linutronix
UBI Fastmap
Slides
Video (45 minutes):
full HD (299M), 800×450 (121M)

Videos of the Embedded track at FOSDEM 2012

Better late than never: we finally found the time to update our video encoding scripts, and therefore encode and upload the videos we had taken of the embedded track at FOSDEM 2012. Amongst many other interesting talks, you’ll notice two talks given by Bootlin engineers: one by Maxime Ripard on the IIO subsystem, a kernel subsystem for Industrial I/O devices, and another by Thomas Petazzoni about the usage of the Qt framework for non-graphical applications in embedded Linux systems.

Cédric BailVideo capture
EFL the upcoming embedded UI toolkit
Slides
Video (51 minutes):
full HD (337M), 800×450 (138M)

Julius Baxter, Olof KindgrenVideo capture
OpenCores.org
The OpenRisc Project
Slides
Video (28 minutes):
full HD (184M), 800×450 (74M)

Jeremy BennettVideo capture
Embecosm
Open Source Software Meets Open Source Hardware, OpenCores and the OpenRisc 1000
Video (28 minutes):
full HD (165M), 800×450 (71M)

Vasilis GeorgitzikisVideo capture
PMH: Home Automation made right
Slides
Video (27 minutes):
full HD (187M), 800×450 (81M)

Thomas PetazzoniVideo capture
Bootlin
Using Qt for non-graphical applications
Slides
Video (47 minutes):
full HD (307M), 800×450 (129M)

Jean PihetVideo capture
Texas Instruments
Linux (SoC) power management
Slides
Video (39 minutes):
full HD (268M), 800×450 (117M)

Maxime RipardVideo capture
Bootlin
IIO, a new subsystem for I/O devices
Slides
Video (35 minutes):
full HD (211M), 800×450 (97M)

Arnoult VandecappelleVideo capture
Mind
Safe upgrade of embedded systems
Slides
Video (47 minutes):
full HD (320M), 800×450 (138M)

Bootlin at the Libre Software Meeting

In a previous post, we detailed all the talks of the Embedded Systems and Open Hardware track of the Libre Software Meeting, taking place in Geneva in early July.

Bootlin will have a quite important presence at this event, with three talks and one tutorial given by Bootlin engineers. You’ll find below the descriptions of the talks given by Bootlin. Both my colleague Maxime Ripard and myself will be present at Libre Software Meeting, and we will be happy to meet you there to discuss Embedded Linux and Android topics!

A look through the Android Stack

Android has established itself in the past years as a major player in the mobile market, outperforming any other mobile systems.

To do so, Google relied both on well established open-source components, such as the Linux Kernel, and munching them together in a brand new userspace environment. This talk will detail the most important components of Android userspace and the interactions between them that allow developers to face a consistent API for their applications.

This talk will be given on Tuesday 9th July 2012, at 14:00, by Maxime Ripard, embedded Linux and Android engineer at Bootlin. Maxime is also teaching our newest training course on Android system development.

Buildroot: a nice, simple and efficient embedded Linux build system

Started in late 2001 by uClibc developers, Buildroot has grown over its 10 years history from a testing tool for the uClibc C library to a complete, vendor-neutral, embedded Linux build system. Until early 2009, the project was mostly unmaintained and the quality slowly decreased, frustrating many Buildroot users. Fortunately, since early 2009, Peter Korsgaard took over the maintainership of Buildroot, and the project has considerably evolved since then: stable releases are published every three months, the user and developer community has grown significantly, the existing features have been cleaned up, many other new features have been added, the project is no longer uClibc-specific and the quality has been vastly improved. Buildroot now offers a nice, simple and efficient mechanism to build small to medium sized embedded Linux systems, such as the ones found in many industrial systems or highly dedicated systems. Many users are amazed about how easy it is to get started with Buildroot, especially compared to other build systems. This presentation will show how Buildroot can be used to build embedded Linux systems, highlighting the new features and improvements made over the last few years, and detailing how the simplicity of Buildroot allows you to focus on developing the applications for your system. A quick overview of the future Buildroot developments will also be provided.

This talk will take place on Wednesday 10th July at 17:00 and will be given by Thomas Petazzoni, embedded Linux engineer at Bootlin, and long time Buildroot contributor.

Linux kernel on ARM: consolidation work

In Spring 2011, Linus Torvalds asked the ARM Linux maintainers to clean up the contents of arch/arm/ in the Linux kernel code by doing more consolidation between ARM sub-architectures.

More than a year later, a lot of work has been accomplished in this area, especially thanks to the introduction of the device tree for the ARM architecture, the pinctrl subsystem and the clock framework into the Linux kernel.

Through this talk, we will present the challenges the ARM architecture creates in terms of Linux kernel support, and then describe from a technical point of view how the device tree, the pinctrl subsystem and the clock subsystem work and how they can improve the consolidation between different ARM sub-architectures.

The talk will be designed to be accessible to an audience having only a moderate knowledge of kernel programming and internals, and will therefore provide enough context for such audience to understand the issues that those different mechanisms are striving to solve.

This talk will take place on Thursday 11th July at 10:00 and will be given by Thomas Petazzoni, embedded Linux engineer at Bootlin.

Tutorial on using Buildroot, a nice, simple and efficient embedded Linux build system

Started in late 2001 by uClibc developers, Buildroot has grown over its 10 years history from a testing tool for the uClibc C library to a complete, vendor-neutral, embedded Linux build system. Until early 2009, the project was mostly unmaintained and the quality slowly decreased, frustrating many Buildroot users. Fortunately, since early 2009, Peter Korsgaard took over the maintainership of Buildroot, and the project has considerably evolved since then: stable releases are published every three months, the user and developer community has grown significantly, the existing features have been cleaned up, many other new features have been added, the project is no longer uClibc-specific and the quality has been vastly improved. Buildroot now offers a nice, simple and efficient mechanism to build small to medium sized embedded Linux systems, such as the ones found in many industrial systems or highly dedicated systems. Many users are amazed about how easy it is to get started with Buildroot, especially compared to other build systems.

This workshop follows the Buildroot presentation proposed in the same topic. During one half-day participants will be introduced on how to efficiently use Buildroot for their own projects:

  • Basic usage of Buildroot: generate the first system, boot it on a hardware platform
  • Add packages to Buildroot
  • Customize Buildroot for real-life projects: how to integrate project specific patches, configuration and customization

Participants are invited to come with their own laptop, installed with a sufficiently recent GNU/Linux distribution. Participants are recommended to attend the Buildroot talk by the same speaker before attending the workshop, as the talk will give an overall introduction on Buildroot.

This tutorial will take place on Thursday 11th July from 14:00 to 17:00 and will be given by Thomas Petazzoni, embedded Linux engineer at Bootlin, and long time Buildroot contributor.