Bootlin contributions to Linux 4.5

Adelie PenguinLinus Torvalds just released Linux 4.5, for which the major new features have been described by LWN.net in three articles: part 1, part 2 and part 3. On a total of 12080 commits, Bootlin contributed 121 patches, almost exactly 1% of the total. Due to its large number of contribution by patch number, Bootlin engineer Boris Brezillon appears in the statistics of top-contributors for the 4.5 kernel in the LWN.net statistics article.

This time around, our important contributions were:

  • Addition of a driver for the Microcrystal rv1805 RTC, by Alexandre Belloni.
  • A huge number of patches touching all NAND controller drivers and the MTD subsystem, from Boris Brezillon. They are the first step of a more general rework of how NAND controllers and NAND chips are handled in the Linux kernel. As Boris explains in the cover letter, his series aims at clarifying the relationship between the mtd and nand_chip structures and hiding NAND framework internals to NAND. […]. This allows removal of some of the boilerplate code done in all NAND controller drivers, but most importantly, it unifies a bit the way NAND chip structures are instantiated.
  • On the support for the Marvell ARM processors:
    • In the mvneta networking driver (used on Armada 370, XP, 38x and soon on Armada 3700): addition of naive RSS support with per-CPU queues, configure XPS support, numerous fixes for potential race conditions.
    • Fix in the Marvell CESA driver
    • Misc improvements to the mv_xor driver for the Marvell XOR engines.
    • After four years of development the 32-bits Marvell EBU platform support is now pretty mature and the majority of patches for this platform now are improvements of existing drivers or bug fixes rather than new hardware support. Of course, the support for the 64-bits Marvell EBU platform has just started, and will require a significant number of patches and contributions to be fully supported upstream, which is an on-going effort.
  • On the support for the Atmel ARM processors:
    • Addition of the support for the L+G VInCo platform.
    • Improvement to the macb network driver to reset the PHY using a GPIO.
    • Fix Ethernet PHY issues on Atmel SAMA5D4
  • On the support for Allwinner ARM processors:
    • Implement audio capture in the sun4i audio driver.
    • Add the support for a special pin controller available on Allwinner A80.

The complete list of our contributions:

Bootlin contributing Linux kernel initial support for Annapurna Labs ARM64 Platform-on-Chip

Annapurna Labs LogoWe are happy to announce that on February 8th 2016 we submitted to the mainline Linux kernel the initial support for Annapurna Labs Alpine v2 Platform-on-Chip based on the 64-bit ARMv8 architecture.

See our patch series:

Annapurna Labs was founded in 2011 in Israel. Annapurna Labs provides 32-bit and 64-bit ARM products including chips and subsystems under the Alpine brand for the home NAS, Gateway and WiFi router equipment, see this page for details. The 32-bit version already has support in the official Linux kernel (see alpine.dtsi), and we have started to add support for the quad core 64-bit version, called Alpine v2, which brings significant performance for the home.

This is our initial contribution and we plan to follow it with additional Alpine v2 functionality in the near future.

“Porting Linux on ARM” seminar road show in France

CaptronicIn December 2015, Bootlin engineer Alexandre Belloni gave a half-day seminar “Porting Linux on ARM” in Toulouse (France) in partnership with french organization Captronic. We published the materials used for the seminar shortly after the event.

We are happy to announce that this seminar will be given in four different cities in France over the next few months:

  • In Montpellier, on April 14th from 2 PM to 6 PM. See this page for details.
  • In Clermont-Ferrand, on April 27th from 2 PM to 6 PM. See this page for details.
  • In Brive, on April 28th from 9 AM to 1 PM. See this page for details.
  • Near Chambéry, on May 25th from 9:30 AM to 5/30 PM. See this page for details.
  • Near Bordeaux, on June 2nd from 2 PM to 6 PM. See this page for details.
  • Near Nancy, on June 16th from 2 PM to 6 PM. See this page for details.

The seminar is delivered in French, and the event is free after registration. The speaker, Alexandre Belloni, has worked on porting botloaders and the Linux kernel on a number of ARM platforms (Atmel, Freescale, Texas Instruments and more) and is the Linux kernel co-maintainer for the RTC subsystem and the support of the Atmel ARM processors.

Bootlin at the Embedded Linux Conference 2016

Like every year for about 10 years, the entire Bootlin engineering team will participate to the next Embedded Linux Conference, taking place on April 4-6 in San Diego, California. For us, participating to such conferences is very important, as it allows to remain up to date with the latest developments in the embedded Linux world, create contacts with other members of the embedded Linux community, and meet the community members we already know and work with on a daily basis via the mailing lists or IRC.

Embedded Linux Conference 2016

Over the years, our engineering team has grown, and with the arrival of two more engineers on March 14, our engineering team now gathers 9 persons, all of whom are going to participate to the Embedded Linux Conference.

As usual, in addition to attending, we also proposed a number of talks, and some of them have been accepted and are visible in the conference schedule:

As usual, our talks are centered around our areas of expertise: hardware support in the Linux kernel, especially for ARM platforms, and build system related topics (Buildroot, Yocto, autotools).

We are looking forward to attending this event, and see many other talks from various speakers: the proposed schedule contains a wide range of topics, many of which look really interesting!

Bootlin speaking at the Linux Collaboration Summit

Bootlin engineers are regular speakers at the Embedded Linux Conference and Embedded Linux Conference Europe events from the Linux Foundation, to which our entire engineering team participates each year.

In 2016, for the first time, we will also be speaking at the Collaboration Summit, an invitation-only event where, as the Linux Foundation presents it, “the world’s thought leaders in open source software and collaborative development convene to share best practices and learn how to manage the largest shared technology investments of our time”.

Collaboration Summit 2016

This event will take place on March 29-31 in Lake Tahoe, California, and the event schedule has been published recently. Bootlin CTO Thomas Petazzoni will be giving a talk Upstreaming hardware support in the Linux kernel: why and how?, during which we will share our experience working with HW manufacturers to bring the support for their hardware to the upstream Linux kernel, discuss the benefits of upstreaming, and best practices to work with upstream.

With a small team of engineers, Bootlin has merged over the last few years thousands of patches in the official Linux kernel, and has several of its engineers having maintainer positions in the Linux kernel community. We are happy to take the opportunity of the Collaboration Summit to share some of our experience, and hopefully encourage and help other companies to participate upstream.