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

Bootlin toolchains 2023.08We 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

DENT project logoThe 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

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, this one being the first of this series.

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.

Releasing Snagboot: a cross-vendor recovery tool for embedded platforms

Recovering and reflashing a bricked board can be a tedious process. It often involves flashing an SD card to bring your device back up, and it gets worse if the board does not have an SD card slot to begin with. Thankfully, most embedded platforms almost always include some form of recovery via USB or UART, which usually involves sending a boot image to the platform’s ROM code. A few tools exist that leverage this functionality to offer quick recovery and reflashing via USB, such as STM32CubeProgrammer, SAM-BA or UUU. However, these tools are all vendor-specific, which means that developers working on various kinds of platforms have to switch between different tools and learn how to use each one.

To address this issue, Bootlin is happy to release today a new recovery and reflashing tool, called Snagboot, which intends to be a generic and open-source replacement to the vendor-specific tools mentioned earlier. It is composed of two parts:

  • snagrecover, which uses vendor-specific ROM code mechanisms to initialize external RAM and run your bootloader (typically U-Boot), without modifying any non-volatile memories.
  • snagflash, which communicates with your bootloader over USB to flash system images to non-volatile memories, using either DFU, USB Mass Storage or fastboot.

Snagboot currently supports about 50 different SoC models, from six different SoC families:

  • STMicroelectronics STM32MP1
  • Microchip SAMA5
  • NXP i.MX6/7/8
  • Texas Instruments AM335x
  • Allwinner Sunxi
  • Texas Instruments AM62x

You can get it from PyPI or browse the sources on github. Our extensive user guide gives all the details on how to setup and use Snagboot on supported platforms. We hope that this tool will be useful to embedded software engineers and that it will continue to grow as support for more SoCs/platforms is added! If you’re familiar with a certain SoC family’s boot process, don’t hesitate to contribute to the project by adding support for your platform!

Yocto Project 4.2 released – Bootlin contributions inside

The Yocto Project has published its new release: 4.2, also known as “Mickledore”.

It features improved Rust support, BitBake engine improvements, support for Linux 6.1 (the latest Long Term Support kernel), new QEMU features, testing improvements and of course many other new features and package updates. See the release notes for all details.

Bootlin has actively contributed to this release, as seen in the number of commits, in particular through our work maintaining the documentation, improving regression detection and on Autobuilder SWAT.

Continue reading “Yocto Project 4.2 released – Bootlin contributions inside”