Bootlin – Page 7 – Embedded Linux and kernel engineering

Embedded Linux audio training course: materials published

End of June, we announced the availability of a brand new training course, Embedded Linux Audio, which is targeted at engineers working with audio on embedded Linux systems, and that covers topics ranging from audio hardware, audio support in the Linux kernel (ASoC, DAI and codec drivers, Device Tree representation), audio support in user-space (alsa-lib, alsa-utils, PipeWire, GStreamer).

We are pleased to announce today that the training materials are now available for download. This again shows our commitment to sharing all our training materials for free, under an open-source license (Creative Commons BY-SA).

This training course has already been given earlier this year to a private customer, and we are releasing the materials before the very first public session, which will take place on September 11 to September 14, and which will be taught by Bootlin engineer and COO Alexandre Belloni. If you’re interested, registration is open, we have a few seats remaining.

Bootlin Embedded Linux course now available on BeaglePlay

Earlier this year, the BeagleBoard.org foundation announced the availability of a new development board, the BeaglePlay, centered around the Texas Instruments AM625 ARM64 processor. Bootlin has for a long time supported the BeagleBone Black as one of the hardware platforms used in the practical labs of its training courses, and we are happy to announce today that we now have added support for the BeaglePlay to our most popular course, the Embedded Linux system development course.

This means that participants to our Embedded Linux system development course can now choose to perform the practical labs on the BeaglePlay, experiencing a new and modern hardware platform, based on an ARM64 processor. This applies not only to participants choosing to purchase our course, but also to everyone else in the world, as our training materials are all freely available and distributed under an open-source license. The materials are all available on our Embedded Linux system development training course page:

We would like to thank Clément Ramirez who has worked with us on this effort of porting this course to the BeaglePlay platform.

“Bootlin is a leading provider of high-quality, in-depth Linux education. What amazes me is how much they not only support open source with outstanding teaching, but how much they stand behind the principles of open source by sharing their teaching materials and contributing to the open source projects that drive them.” said Jason Kridner, founder of BeagleBoard.org. “BeagleBoard.org shares these principles and that is why I believe BeaglePlay is an excellent choice. BeaglePlay doesn’t just run open source software, the hardware itself is open source with detailed documentation on the board and associated Texas Instruments AM625 system-on-chip, with availability to enable hobbyists and professionals alike from prototype to production. I couldn’t be more excited.”

Bootlin’s Embedded Linux course, like all our training courses, is available in 3 different options:

Public on-line sessions, delivered by video-conference, with a per-participant registration, and sessions organized at dates scheduled by Bootlin. See this page for more details, dates and registration process
Private on-line sessions, also delivered by video-conference, organized privately for your team, at the date of your choice. See this page for more details
Private on-site sessions, where one of our experienced engineers and trainers travels to your location, to teach your team in person. See this page for more details

In both our private on-line sessions and private on-site sessions, our customers are free to chose, among our set of supported platforms, the HW platform they would like to use for the practical labs, and this now includes the BeaglePlay. In our public on-line sessions, the trainer demonstrates the practical labs on one particular platform, but participants are able to reproduce the labs on the platform of their choice among our supported platforms.

With this new development, we look forward to continue our mission of helping the broader engineering community get trained on embedded Linux technology and expand the number of users and contributors to open-source technologies and communities.

Feedback from ELCE 2023: selection of talks #2

As we reported in previous blog post, almost the entire Bootlin engineering team was at the Embedded Linux Conference Europe in Prague in June. In order to share with our readers more about what happened at this conference, we have asked all engineers at Bootlin to select one talk they found interesting and useful and share a short summary of it. We will share this feedback in a series of blog post: first post, this one being the second post.

Continue reading “Feedback from ELCE 2023: selection of talks #2”

Bootlin toolchains 2023.08 released

We are happy to announce that we have just published a new update of our freely available toolchains at toolchains.bootlin.com, version 2023.08.

For the record, we provide pre-built cross-compilation toolchains that work on x86-64 Linux machines, and targeting 43 different CPU architecture variants, with support for all 3 major C libraries: glibc, musl and uClibc-ng. For each toolchain, we provide two versions: a stable one that uses GCC/binutils/GDB versions next to the last, and a bleeding-edge one that uses the very latest GCC/binutils/GDB versions.

In this 2023.08 release, we have:

Updated the bleeding-edge toolchains to gcc 13.2, binutils 2.41, gdb 13.2, kernel headers 5.10, glibc 2.37, musl 1.2.4 or uclibc-ng 1.0.43
Updated the stable toolchains to gcc 12.3, binutils 2.40, gdb 12.1, kernel headers 4.14, glibc 2.37, musl 1.2.4 or uclibc-ng 1.0.43
Marked the sparcv8 toolchain as obsolete as sparc support in GCC has been broken for several releases, and the last working version of GCC for sparc has been dropped from Buildroot

A special thanks to Romain Naour from Smile who helped investigate and resolve some of the issues encountered in the preparation of those 2023.08 toolchains.

If you encounter any issue in the usage of those toolchains, or miss the support for a specific feature or architecture variant, let us know through the issue tracker. We hope those toolchains will continue to be useful to the community.

Bootlin collaborates with DENT to upstream ONIE NVMEM support in Linux

The DENT project is a project from the Linux Foundation which aims at utilizing the Linux Kernel, Switchdev, and other Linux based projects as the basis for building a new standardized network operating system without abstractions or overhead.

Recently, Bootlin collaborated with the DENT project to work on a specific topic: extending the Linux kernel NVMEM subsystem to be able to support the ONIE TLV storage format which is used on ONIE-compliant network equipment to store in an EEPROM various information about the device: serial number, model, MAC addresses, and more.

This work, lead by Bootlin engineer Miquèl Raynal has now landed in Linux 6.4 as the drivers/nvmem/layouts/onie-tlv.c driver, together with the underlying new NVMEM layout infrastructure, which Miquèl helped to upstream in collaboration with Michael Walle.

We have written and published a longer blog post on the DENT website to explain the motivation for this effort and the results.

Feedback from ELCE 2023: selection of talks #1

Continue reading “Feedback from ELCE 2023: selection of talks #1”

Back from the Embedded Linux Conference Europe 2023

From June 28 to June 30, Bootlin participated to the Embedded Linux Conference Europe, which was organized as part of the new and larger Embedded Open Source Summit.

In addition, the day before the conference, on June 27, our team had a great team building event, spending the day visiting Prague, having lunch in a traditional restaurant, enjoying a boat tour on the Vltava river, and an evening with a traditional dinner and folklore music. As our team is distributed, conferences are a great opportunity to meet each other and Prague was for several members of our team their first in-person meeting.

With 14 Bootlin engineers at the conference, almost our entire engineering team participated. Indeed, we have a policy at Bootlin to offer to all our engineers, regardless of their seniority level, the chance of attending 2 technical conferences each year.

Continue reading “Back from the Embedded Linux Conference Europe 2023”

Welcome to Thomas Richard

Welcome on board! Bootlin is really happy to welcome another engineer in its team: Thomas Richard, who joined us on July 3, 2023 (missing a participation to the Embedded Linux Conference Europe by just one week!).

Thomas graduated from INSA Toulouse in 2015, and then started his embedded software engineer career at Kontron, where he worked on numerous aspects of embedded Linux system development:

Thomas developed an OpenWRT based embedded Linux OS for railway systems, including virtualization support and security features such as TPM-based secret sealing, Host Intrusion Detection System (HIDS), and Linux Security Modules (LSM)
Thomas used both Yocto and Buildroot as build systems to create custom embedded Linux systems, in particular to support VME/VPX boards.
Thomas has developed several Linux kernel drivers, for GPIOs, HDLC, UART, watchdog, and more, to address the needs of several Kontron products
Thomas has also worked on cyber-security challenges, by creating a streamlined process to merge results from different vulnerability scanners and generate comprehensive reports for customers, to allow them to keep their embedded Linux systems updated in terms of security fixes.

Thomas is joining our team located in Lyon, France, where he will work at our office with Alexandre Belloni, Grégory Clement, Théo Lebrun and Kamel Bouhara, and of course with the rest of our team in Toulouse and remote.

For more details, see Thomas’ page on Bootlin.com or his LinkedIn profile.

Linux 6.4 released, Bootlin contributions inside

Linux 6.4 was released on June 25, just before the start of the Embedded Open Source Summit in Prague. As usual, lots of changes in Linux 6.4, and we recommend reading LWN coverage of the merge window (part 1, part 2). Sadly, the usual KernelNewbies page hasn’t received a lot of attention, contributions are probably welcome to revive this useful resource.

With 59 commits from Bootlin engineers, Bootlin is ranked as the #28 contributing company by number of commits for this 6.4 release, according to contribution statistics. Our main contributions have been:

Alexis Lothoré and Clément Léger contributed a few fixes to the Renesas RZ/N1 A5PSW Ethernet switch driver
Hervé Codina contributed a number of new drivers needed to support complex audio setups on some relatively old Freescale PowerPC 32-bit platforms: a driver for the Time Slot Assigner (TSA), a driver for the QUICC Multichannel Controller (QMC), and an ALSA driver that provides audio support over QMC. We have more contributions coming in this area, most notably to support HDLC network traffic over QMC.
Kamel Bouhara added support for the TI TAS5733 audio codec in the existing tas571x driver
Luca Ceresoli improved the fsl-ldb driver, used on NXP i.MX8MP and i.MX93 for the built-in DPI-to-LVDS encoder. Luca’s improvement allows to use LVDS channel 1 only, while the driver initially supported using either LVDS channel 0, or LVDS channel 0 and 1 combined.
Maxime Chevallier contributed an improvement to the regmap code, which allows upshifting register addresses before performing operations
Maxime Chevallier also contributed some small fixes to the phylink code related to previous work on QUSGMII support
Miquèl Raynal contributed the support for Real-While-Write in the MTD SPI-NOR subsystem. This allows to perform read operations while erase/program operations are on-going, which helps to reduce read latencies. This of course only works on SPI NOR chips that support this feature.
Miquèl Raynal contributed several improvements to the NVMEM subsystem. First, a brand new NVMEM driver capable of parsing the ONIE TLV information, as defined by the ONIE spec used on network equipment. Second, he contributed changes that allow NVMEM layout drivers to be compiled as kernel modules rather than being built-in

And the full details of our contributions:

New training course: Embedded Linux Audio

Embedded Linux Audio training course — Image from flaticon.com

We are very happy to announce the availability of a new training course in our portfolio: Embedded Linux audio.

Over the past years, Bootlin has helped more and more of its customers with numerous audio aspects on embedded Linux systems: development of Linux kernel drivers for audio components, description of audio hardware in Device Tree, support of unusual audio hardware setups, integration of user-space audio frameworks and servers such as PipeWire, and more. We have seen an interest from our customers and the broader community in getting trained on those topics, so we have built a brand new training course covering the following:

Digital Audio Representation
Audio hardware
Linux kernel ASoC subsystem
Linux kernel helpers for audio
Audio routing
More kernel audio components
Audio troubleshooting and debugging
User-space configuration for audio hardware
User-space configuration for audio controls
User-space APIs to play and capture audio
PipeWire
GStreamer

The detailed agenda of course is available for on-line sessions (4 half-days of 4 hours each) and on-site sessions (2 days). As usual with Bootlin, our training materials will be published for free under an open-source license in the next few weeks.

This course has been developed and is taught by Bootlin expert Alexandre Belloni.

We have a first public on-line session scheduled on September 11-14 2023, with a possible extra session on September 15. Sessions take place from 2 PM to 6 PM UTC+2 on each day. Seats are offered at 619 EUR per participant, with a discount at 519 EUR per participant under conditions. You can book your seat now, beware that only 12 seats are available.

This new training course is the 9th training course we offer in our portfolio, with all courses centered around embedded Linux development. We aim at developing more of those specific courses in the next few years, to continue to help engineers working on embedded Linux grow their skills and expertise.