Thomas Petazzoni is Bootlin's co-owner and CEO. Thomas joined Bootlin in 2008 as a kernel and embedded Linux engineer, became CTO in 2013, and co-owner/CEO in 2021. More details...
Paris will be hosting next week-end a combined event composed of the Open Source Experience and SIDO, the first dedicated to open-source technologies, and the second to IoT, AI, digital infrastructure and cybersecurity.
Thomas Petazzoni, Bootlin CEO, will be representing Bootlin at these events, and will also be participating to the round table Embedded systems security: a technical and organizational approach on December 7, at 2:30 PM UTC+1. The abstract of the round table is:
Security is a major issue. Embedded systems are increasingly complex and connected, making them more vulnerable. The aim of this round table is to discuss best practices for guaranteeing security
Thomas will be speaking with Daniel Fages (Freelance), Eloi Bail (Savoir Faire Linux) and Jean-Charles Verdié (Canonical), and the round table will be moderated by Cédric Ravalec (Smile).
If you’re interested in discussing career, business or partnership opportunities with Bootlin, do not hesitate to contact Thomas Petazzoni ahead of the event to schedule a meeting.
For close to 20 years, Bootlin has offered to companies around the world its expertise in embedded Linux system development, with engineering and training services covering low-level software development in the Linux kernel and open-source bootloaders, as well as embedded Linux system integration and build systems.
Bootlin’s expertise is obviously tightly coupled with hardware engineering, as the low-level software we develop runs on a wide variety of hardware platforms, sometimes with complex designs. As experts in low-level software, our team possesses a robust understanding of the hardware used in embedded systems, including SoCs, board design, hardware interfaces, and protocols.
Today, we are delighted to announce a strategic partnership with Ratiotech, marking a significant expansion of our collective expertise. Ratiotech brings an impressive 25 years of experience in hardware design, electronic systems, signal integrity, and EMC.
This partnership enables:
Bootlin to offer significantly deeper and broader expertise in investigating, debugging, and resolving issues during the bring-up of our customers’ hardware platforms
Ratiotech to leverage Bootlin’s solid expertise in embedded Linux development, providing customers with a comprehensive range of services covering both hardware development and Linux operating system integration
A collaboration that allows Bootlin and Ratiotech to provide turn-key solutions, encompassing the entire development of hardware/software solutions: hardware design, industrialization, low-level software development on microcontrollers, porting and integration of embedded Linux systems, and application development
Commencing in early 2024, Bootlin and Ratiotech will share offices near Toulouse, France, facilitating a seamless collaboration between the teams of both companies to ensure the success of this partnership.
Ratiotech’s CEO, Fabien Hue, states, “This strategic partnership is an excellent step to accelerate the development of Ratiotech and offer our customers a broader expertise, fully complementing Bootlin’s expertise in embedded Linux systems.”
Thomas Petazzoni, Bootlin’s CEO, adds, “The expertise and offerings provided by Bootlin to its customers will be significantly enhanced through this partnership with Ratiotech. This close relationship will not only expedite the bring-up of new hardware platforms but also enable us to offer essential hardware development, debugging, and investigation expertise that many of our customers require. We are eagerly looking forward to further assisting our customers with Ratiotech’s expertise.”
For more details on this partnership, check our hardware expertise, and for more details about Ratiotech, visit their website at Ratiotech.
Capitole du Libre is THE open-source/free-software event that takes place each year in Toulouse, France. Turns out that half of Bootlin’s team is precisely based in Toulouse, and obviously we are big fan of open-source/free-software, and therefore we have always supported, contributed and participated to Capitole du Libre in one way or another. Bootlin’s CEO Thomas Petazzoni is actually one of the founders of the Capitole du Libre event, back in 2007-2008.
This year, Capitole du Libre will take place on November 18-19, as usual at ENSEEIHT, an engineer school located in the heart of Toulouse.
Bootlin is first financially supporting the event by being one of the Platine sponsors. Thanks to this, we will have a booth at the event, so if you want to meet us, coming to Capitole du Libre is a good idea.
Secondly, Bootlin is also contributed to the event by having 4 of its engineers give talks:
Attending Capitole du Libre is free, so we definitely recommend all free-software/open-source users, developers, contributors to join this great event, and we look forward to meeting the local open-source community at Capitole du Libre!
Linux 6.6 was released yesterday, so this is the time for our usual blog post about our contributions to this release. Before that, to get an overall idea of what went into Linux 6.6, we recommend reading the articles from LWN.net covering the Linux 6.6 merge window: part 1 and part 2. The KernelNewbies page is perhaps a little bit less rich than it used to be, but still relevant.
On our side, this time around we contributed 68 changes to this release:
Alexandre Belloni, as the RTC subsystem maintainer, submitted a few asorted patches touching various drivers in this subsystem
Alexis Lothoré pushed some patches extending the rzn1-a5psw Ethernet switch driver with VLAN support and port_bridge_flags support. These patches were initially written by Clément Léger but had not been accepted until now.
Hervé Codina got his audio-iio-aux driver merged, which allows the ASoC subsystem (for audio devices) to use IIO devices, such as a potentiometer. This came together with a number of fixes/improvements in the IIO subsystem. Hervé also fixed some reference counting issues in several I2C mux drivers.
Miquèl Raynal pushed to the finish line a patch written several years ago by Bootlin engineer Kamel Bouhara, who hadn’t been accepted until now. This patch adds a sysfs interface that allows to retrieve the reset reason on Microchip ARM platforms
Luca Ceresoli fixed some issues in two DRM panel drivers and also fixed a regression in the NVidia Tegra camera interface driver
Miquèl Raynal did a number of different, unrelated, contributions:
support for the EDT ET028013DMA display panel to the existing sitronix-st7789v driver, which required quite a few preparation changes
fix a clock polarity issue in the DRM driver for the display controller used in Microchip ARM platforms
improve many small aspects of the qcom NAND controller driver
improve the handling of nvmem layouts in the nvmem subsystem
fix an issue in the SJA1000 CAN controller driver that would cause the HW to stall after an overrun on some platforms
Paul Kocialkowski contributed a few small asorted fixes in the media subsystem documentation
Here are the complete details of our contributions:
The Yocto Project regularly organizes an-online conference called the Yocto Project Summit. The next edition, Yocto Project Summit 2023.11 will take place on November 28-30, from 12:00 to 18:00 UTC, and at just $40, attending is really affordable.
Bootlin is not only a big user of the Yocto Project, but also a significant contributor to the project, so we’re happy to announce that our two talk proposals for the Yocto Project Summit 2023.11 have been accepted. Bootlin engineers will therefore deliver the following talks:
If you are a user of the Yocto Project, or intend to become one, we can only recommend you to attend this event. And of course, if you need training on Yocto Project, or engineering/support services, do not hesitate to contact us!
Bootlin is happy to announce its list of internship topics for 2024, which are open to students in engineering schools or similar, from France or the European Union. Our internship booklet is in French as most of our interns come from France.
The proposed topics are as follows:
Drivers and hardware support in Linux or U-Boot
Improvement of the Elixir code navigation service
Security tracking of Linux BSP
Implementation of a reference secure embedded Linux OS
Addition of USB composite gadget support in U-Boot
Improvement of IEEE 802.15.4 support in Linux
Open topic related to embedded Linux
Bootlin is a company with a strong open-source focus: the results of the internships will be contributed to the corresponding open-source projects and will lead to the publication of blog articles or public presentations. In addition, interns will have the opportunity to work with a team of engineers with strong expertise in embedded Linux and open-source contributions.
The internships are offered for 2024, with flexible start dates, but for a minimum duration of 4 months. These internships will take place either in our offices in the Toulouse area (Colomiers) or in the Lyon area (Oullins), in order to be integrated into our team of engineers. These internships are open to all students who are citizens of the European Union.
Although several internship positions are offered, Bootlin will host a maximum of 2 interns simultaneously, in order to provide interns with high-quality supervision and guidance from Bootlin’s engineers.
For any questions or applications regarding these internship offers, please contact jobs@bootlin.com.
Bootlin will be at the Netdev 0x17 conference, subtitled THE Technical Conference on Linux Networking. It is indeed one of the major event for developers working on the networking side of the Linux kernel to gather and discuss current and future topics. This year, the conference will take place from Oct 30 to Nov 3 in Vancouver, Canada.
Bootlin is involved in a number of Linux kernel networking developments: development and/or improvement of Linux kernel drivers for Ethernet MACs, Ethernet PHYs, WiFi chips, support for SFP, for Ethernet switches, for PTP offloading, for MACsec offloading, improvements to the 802.15.4 stack, and more. As such, it is very relevant for us to meet the Linux kernel networking community, present our work, and understand where things are heading to in the networking stack.
This talk will describe current use-cases where one MAC is connected to multiple PHYs (chained, or in parallel) and multiple front-facing ports, either through multiple PHYs or through a single multi-port PHY. There exist support for some of these scenarios already, but it is limited by the fact that the PHY device is hidden behind a net_device from userspace’s point of view. We therefore can’t configure an individual PHY when multiple PHYs are present on a link (through SFP transceivers for example), and selecting which front-facing port to use is also limited. This talk will describe ongoing work to support these complex topologies, the challenges faced and expected improvements.
We look forward to attending this event in a few weeks time!
As we reported in a 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 posts: first post, second post, third post, this one being the fourth and final post of the series.
Do the Time Warp – the Rocky Horror PTP Show: Verification of Network Time Synchronization in the Real World
Talk by Johannes Zink, chosen by Bootlin engineer Köry Maincent
As we are currently dealing with PTP at Bootlin and facing several weird behaviors, this talk resonated well with our current state of mind. Currently, most of our clock usage uses NTP but some specific usage may need PTP to have high-precision clock synchronization between devices.
In this talk, Johannes first describes briefly the principles of PTP and its implementation in the Linux kernel, where the PTP is either managed by the MAC (often), the PHY or by software, and Userspace, with the description of the Linuxptp project. Then he goes straight to the issues he faced. For non-PTP users, it might be a bit harsh to follow the tests and oscilloscope measurements described by Johannes. He describes several possible issues and clock behaviors you can face, which might help a new PTP user to not spend too much time on debugging some tricky PTP behavior. Also one of the important things he notices is to “Always check your assumptions!”, which he wants to spread as a religious mantra. Using his common pitfalls and best practices may be a good thing when putting a hand in the PTP mechanism.
And don’t forget “Always check your assumptions!”!
As a Yocto user, you may have already wondered, ‘Why aren’t there official tools for creating and managing BitBake-based projects in a reproducible manner?’ Perhaps you have already used tools like repo, Git submodules, kas, or even created your own scripts.
In this talk, Alexander Kanavin – one of the major contributors to the Yocto project – introduces the tools currently under development within OE-core/poky to address this situation.
WirePlumber 0.5 Propelling PipeWire for the Embedded
Talk by Ashok Sidipotu, chosen by Bootlin engineer Alexandre Belloni
Ashok started to present a quick introduction to what Pipewire is. A nice block diagram explains what it looks like in action. Then the discussion switches to the session manager and why it is important. WirePlumber is now the default session manager, replacing PipeWire media session. It manages the control path and dynamically creates PipeWire objects.
The main changes are:
config syntax is switching from Lua to SPA JSON, just like PipeWire. More info is available is this blog post
the event dispatcher has been created to handle PipeWire signals. This allows to prioritize signals and to avoid race conditions. This feature has a nice example and a fairly complete blog post
This talk is a nice overview of what is happening in the PipeWire ecosystem which is now quite mature. It is also great to see the improvements and that the embedded use case is not forgotten.
We are pleased to welcome two additional engineers to our team based in Toulouse, France: Romain Gantois and Louis Chauvet.
Romain Gantois graduated from ISEP and completed his final internship at Bootlin during which he developed and published Snagboot, the generic and open-source board recovery and reflashing tool, and worked on an upstream Linux kernel driver for a Qualcomm Ethernet switch (patches will be submitted soon!). Following this internship, Romain is joining our team as a full-time embedded Linux and Linux engineer.
Louis Chauvet graduated from INSA Toulouse. He completed his final internship abroad, during which he worked on developing in Rust, in particular the development of Linux kernel drivers in Rust. Louis is also joining us as a full-time embedded Linux and Linux kernel engineer.
Both Romain and Louis are experienced Linux users and developers, with a solid education in low-level and embedded systems development. They will help us address more embedded Linux projects from our customers on a wide variety of topics, and are already benefiting from our training courses and the interaction with our senior engineers to quickly gain even more knowledge and experience.
As we reported in a 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, second post, this one being the third of the series.
rtla timerlat: Debugging Real-time Linux Scheduling Latency
Talk by Daniel Bristot de Oliveira, chosen by Bootlin engineer Maxime Chevallier.
Talks related to real-time linux debugging are pretty common at ELCE, I gave one myself in 2017 and I’ve been attending most of them since then. Besides a headache, what I could get from attending all these talks is that this topic is complex, time consuming, and that there’s a lot of different methodologies one can use to find the cause of these elusive problems.
Users who aren’t very familiar with the inner workings of the Linux Kernel can ask for help on mailing-lists, and the reply usually asks for a trace. This is where things get complicated, the Linux kernel tracer is very powerful, but can drown users in a flood of trace events from which it is difficult to extract the relevant data.
Hopefully, Daniel’s talk is going to make this kind of talk less common, as the tool he wrote and presented, rtla, makes it easy to gather important information about the cause of undesired latencies. By using cleverly placed trace-points, in-kernel testing tools (timerlat and osnoise) and an automated trace analyzer, rtla can not only detect latencies as cyclictest would, it can also give you what caused the latency. If it’s a blocking problem, rtla tells you which process is blocking your task. If it’s an interference, rtla will tell you which task or interrupt caused the latency, and can even detect if the hardware itself is the culprit.
For developers, this tool is also a perfect way to gather user feedback and bug reports that are small, precise and easily reproducible.
I therefore strongly recommend checking out Daniel’s talk and his dedicated blog article.
Zbus – the Lightweight and Flexible Zephyr Message Bus
Talk by Robrigo Peixoto, chosen by Bootlin engineer Thomas Perrot
Zbus is a new message bus for Zephyr allowing threads to communicate to many others, easily. This bus allows to implement several bus topologies:
one-to-one
one-to-many
Many-to-many
In addition, it can be used on very constrained systems.
In this talk, Rodrigo explained in detail how Zbus works, through a few examples. A thread can read or publish in bus channels, and when a message is published into a channel:
The Listener’s callbacks are executed
A notification is put to the subscriber’s queues
Then the subscriber will be executed by priority order
The bus is managed by a dispatcher, named Virtual Distributed Event Dispatcher (VDED) that is robust to priority inversion.
We found Zbus to be a very interesting feature because before there was no easy way to implement one-to-many and many-to-many topologies, but also one-to-one communications without having to manage the problems of inverting priorities and to use FIFO, LIFO, pipe, etc.
Linux Power ! (from the Perspective of a PMIC Vendor)
Talk by Matti Vaittinen, chosen by Bootlin engineer Kamel Bouhara.
PMICs (Power Management Integrated Circuit) are a key component of low power embedded systems as they often handle complexity in controlling various power voltages required by SoCs. In his talk Matti Vaittinen started by depicting the various devices that can be embedded in a PMIC (Power Management Integrated Circuit): watchdog, RTC, GPIOs are examples of such extra functionalities. He reminded us the reason why such devices are best fitted in the Linux MFD subsystem to take advantage of existing code. However the main subsystem used to implement support for a PMIC is the regulator subsystem and the talk gives us a good understanding of how it works, the concept of provider/consumer, how to register multiple regulators for a PMIC and how to handle specific events. A focus is made on error detection and how over current errors are reported over three categories:
PROTECTION : hardware level errors reported when protection limit is reached
ERROR: Unrecoverable errors that don’t directly involve hardware shutdown.
WARNING: System is still recoverable but requires specific action to be taken
Some PMICs also provide IRQs to notify errors or events and the kernel provides a helper function to handle such notifications and map them to specific actions depending on their severity.
Overall, we found this talk interesting to understand bettert the features provided by PMICs, and how these features are supported by Linux.
Bootlin will be at the 
We are pleased to welcome two additional engineers to our team based in Toulouse, France: