2015 Q1 newsletter

The Bootlin team wishes you a Happy New Year for 2015, with plenty of optimism and energy!

Bootlin is happy to take this opportunity to share some news about the latest training and contribution activities of the company.

Kernel contributions

We continue to work significantly on support for various ARM processors in the Linux kernel. Our contributions to the latest kernel releases:

  • 147 patches from Bootlin merged in Linux 3.17, making Bootlin the 14th contributing company for this release by number of patches. See our blog post about this release.
  • 155 patches from Bootlin merged in Linux 3.18, making Bootlin the 14th contributing company. See our blog post for more details.
  • For the upcoming 3.19 release, we already have 196 patches merged.

One of the highlights was that we added support for the Atmel SAMA5D4 SoC to the Linux kernel even before the new chip was announced by Atmel! That’s a very positive sign for customers when an SoC is supported in the mainline Linux kernel sources right at product launch, instead of having to wait for months or years before the community developers can catch up.

Note that we also added Atmel SAMA5D3 SoC support to Xenomai, a hard real-time extension for the Linux kernel. Thanks to this, the Atmel SAMA5D3 Xplained board can now run with the 2.6.x release of Xenomai.

Besides those highlights, most of our kernel contributions were as usual centered around support for specific families of ARM processors: CPUs from Marvell EBU and Marvell Berlin, from Atmel and from Allwinner. We added a new network driver for some Marvell EBU processors, added SMP support for Marvell Berlin processors, added a DMA controller driver for Allwinner processors, and did a lot of maintenance work to support these processors in the mainline kernel.

Buildroot contributions

Our involvement into the Buildroot project, a popular embedded Linux build system, is going on. Our engineer Thomas Petazzoni contributed 136 patches to the 2014.11 release, making him the second contributor by number of patches. Thomas is also taking care of the maintenance of the project on a more regular basis, reviewing and merging patches from contributors.

OpenWRT contributions

We have recently started contributing to the OpenWRT project: improve the kernel support to use defconfig, introduce a notion of board to support different NAND configurations for each platform. We will soon to be pushing support for the Marvell Armada 385 platform, and improved support for the Marvell Armada 370 and XP platforms.

Recent projects

Besides our publicly visible kernel contributions, we do also work on customer-specific projects. Among the latest projects we have done:

  • Develop a complete Board Support Package for a custom TI AM335x based platform: U-Boot porting, Linux kernel porting, and development of a Yocto-generated system. Qt5 and OpenGL are used for the graphical application, a fairly complex audio setup had to be supported, and many traditional interfaces as well (USB Host and Device, CAN, display, etc.)
  • Develop a Board Support Package for a custom Marvell Armada 375 based platform for a telephony system. Not only did we port a Linux kernel on this platform, but we also wrote several DAHDI drivers to interface the telephony hardware of the platform with Asterisk.
  • NAND and UBI stress-testing for a customer-specific Freescale i.MX28 based platform. We improved the NAND controller driver, added a new MTD tool to generate bitflips, and did some long term power-cut stress-testing of the UBIFS setup to ensure the reliability of the platform. See our kernel driver improvements and the new nandflipbits tool.
  • Adapt an existing ADC driver for a customer-specific platform to the modern Industrial Input Output (IIO) subsystem of the kernel.

Conferences: FOSDEM, Embedded World and Embedded Linux Conference

Several Bootlin engineers will participate to the FOSDEM conference, taking place on January 30 and February 1 in Brussels. In addition, Thomas Petazzoni will be participating to the Buildroot Developers Meeting that takes place right after FOSDEM in the Google offices in Brussels.

Bootlin will participate to the Embedded World trade show on February 24-26 in Nuremberg, Germany. We will be present at Atmel’s booth and visiting exhibitor booths too. For people in Europe, this will be a good opportunity to ask your questions about our embedded Linux training and engineering services. In particular, you will be able meet our engineers Alexandre Belloni, Thomas Petazzoni (CTO), Michael Opdenacker (CEO) and Anja Roubin as well, the new person in charge of our training services.

This year again, most of the Bootlin engineering team (7 engineers) will participate to the 2015 edition of the Embedded Linux Conference on March 23-25 in San Jose, California. We submitted several talk proposals, but our presence won’t depend on the number of talks that are eventually accepted. Participating to this conference, and to its European edition in the fall too, is very important for us to make sure we do not miss any of the interesting developments in the technical community, and above all to strengthen our ties with the community developers. This helps us to be good technical trainers with valuable experience and information to share. The strong relationships with other community developers (and in particular with project maintainers) also help us when our customers contract us to add hardware support or features to official versions of community projects such as the Linux kernel.

Free technical documentation resources

Since the latest edition of this newsletter, we started running our new Yocto Project and OpenEmbedded course, and we released all training materials for this course. As usual, such materials are meant to be used by people learning by themselves too. All you have to do is get your hands on a Beaglebone Black board, read the slides and try to do the labs!

Our engineer Maxime Ripard also contributed documentation about the DMAEngine subsystem in the Linux kernel.

Upcoming training sessions – Now in Paris too!

The news is that we will run new public sessions in Paris, in addition to the ones we usually organize in Toulouse, Avignon and Lyon in France. We are starting with our embedded Linux and our Yocto courses, but other topics will follow too.

So, here are our next session dates:

See sessions and dates for more details. Of course, we can also deliver our training courses at your location, anywhere in the world. Feel free to contact us for a quote.

If you are interested in more frequent news about Bootlin, you can follow us on Twitter, Google+ and LinkedIn.

Linux 3.18 released, Bootlin 13th contributing company

PenguinLinus Torvalds has recently released the 3.18 version of the Linux kernel. As usual, LWN.net made an excellent coverage of the merge window: part 1, part 2 and part 3.

As of 3.18-rc6, LWN.net gathered some statistics about the 3.18 kernel contributions, and Bootlin is ranked as the 13th contributing company for this release in number of patches (see the statistics), right after MEV Limited and before Qualcomm.

A quick summary of our contributions:

  • Improvements to the support of Atmel ARM processors: addition of a memory driver for the RAM controller (Alexandre Belloni), improvements to the irqchip driver to support the new SAMA5D4 processor (Alexandre Belloni), updates to the defconfigs (Alexandre Belloni), new clock driver for the SAMA5D4 processor (Alexandre Belloni), preparation work for multi-platform (Boris Brezillon), numerous fixes to clock drivers (Boris Brezillon), NAND driver improvements (Boris Brezillon), new reset and poweroff drivers and moved all the corresponding logic to a Device Tree based description (Maxime Ripard), refactoring of the clocksource driver and move to the proper drivers/clocksource directory (Maxime Ripard).
  • Improvements to the support of Marvell EBU ARM processors: XOR driver improvements (Ezequiel Garcia), pin-muxing description in Device Tree for more platforms (Ezequiel Garcia), support for the RTC on Armada 375 (Grégory Clement), support for the Spread Sprectrum Generator on Armada 370 (Grégory Clement), improvements to the support of the Armada 370 RD platform (Thomas Petazzoni), extensions to the cpufreq-dt driver to support platforms with independent clocks for each CPU, various fixes.
  • Improvements to the support of Marvell Berlin ARM processors: add support for the Ethernet controller by re-using the existing pxa168_eth driver (Antoine Ténart).
  • Improvements to the support of Allwinner ARM processors: addition of the support for a phase property to the Common Clock Framework, and usage in the context of the MMC clock on Allwinner processors (Maxime Ripard).
  • Various small UBI improvements (Ezequiel Garcia).
  • A number of trivial fixes: removal of IRQF_DISABLED, typo fixes, etc. (Michael Opdenacker).

The detailed list of the patches we have contributed:

DMAEngine Documentation: Work (finally) in Progress

While developping a DMA controller driver for the Allwinner A31 SoCs (that eventually got merged in the 3.17 kernel), I’ve realised how under-documented the DMAEngine kernel subsystem was, especially for a newcomer like I was.

After discussing this with a few other kernel developers in the same situation, I finally started to work on such a documentation during the summer, and ended up submitting it at the end of July. As you might expect, it triggered a lot of questions, comments and discussions that enhanced a lot the documentation itself but also pointed out some inconsistencies in the API, obscure areas or just enhancements.

This also triggered an effort to clean up these areas, and hopefully, a lot more will follow, allowing to eventually clean up the framework as a whole.

And the good thing is that this documentation has been merged by the DMAEngine maintainer and is visible in linux-next, feel free to read it, and enhance it!

Linux 3.17 released, Bootlin 14th contributing company

PenguinLinux 3.17 has been released a few days ago. One can read the coverage of the 3.17 merge window by LWN (part 1 and part 2) to get some details about the new features brought by this kernel release.

As usual, Bootlin has continued to contribute a significant number of patches to this kernel release, even though with 147 patches, our contribution has been less important than for the 3.16 release for which we contributed 388 patches. With 147 patches merged, Bootlin is the 14th contributing company by the number of patches, according to the statistics.

Our contributions remain mainly focused on support for various families of ARM processors:

  • For the Atmel processors
    • Switched to use the generic PWM framework instead of custom PWM drivers. This allowed to remove three obsolete drivers (a backlight driver, a LED driver and a misc driver). This work was done by Alexandre Belloni.
    • Continue the migration to the common clock framework, by adding clock information to a large number of Atmel boards. Done by Alexandre Belloni.
    • Migration of the interrupt controller driver from arch/arm/mach-at91 to drivers/irqchip. Done by Boris Brezillon.
  • For the Marvell EBU processors (Armada 370, 375, 38x, XP)
    • Addition of the mvpp2 network driver, which is used on the Armada 375 SoC. This work was done by Marcin Wojtas from Semihalf, with a lot of review, help and debugging done by Ezequiel Garcia.
    • Addition of cpuidle support for Armada 370 and Armada 38x. This work was done by Grégory Clement and Thomas Petazzoni.
    • Preparation work to enable cpufreq on Armada XP was merged. However the feature cannot be enabled yet due to missing features in the cpufreq-cpu0 driver. Done by Thomas Petazzoni.
  • For Marvell Berlin processors
    • SMP support has been added. Done by Antoine Ténart.
    • Description of the I2C controller has been added to the Device Tree. Done by Antoine Ténart.
    • Support for AHCI has been added. Also done by Antoine Ténart.
  • For Allwinner processors
    • New DMA controller driver for the DMA engine of the Allwinner A31 SoC. Done by Maxime Ripard.
    • A number of fixes and improvements to the pin-muxing driver for Allwinner platforms. Done by Maxime Ripard.
    • Support for the Merrii A31 Hummingbird board has been added. Done by Maxime Ripard.
  • Other changes
    • Addition of a helper function to convert an ONFI timing mode into the according NAND timings. Done by Boris Brezillon.
    • Addition of a driver for the Foxlink FL500WVR00-A0T panel. Done by Boris Brezillon.

The detailed list of our contributions:

Atmel SAMA5D4 support in the mainline Linux kernel

Atmel SAMA5D4Atmel announced its new ARM Cortex-A5-based SoC on October 1, the SAMA5D4. Compared to the previous Cortex-A5 SoC from Atmel, the SAMA5D3, this new version brings a L2 cache, NEON, a slightly different clock tree, a hardware video decoder, and Trustzone support.

Bootlin engineers have worked since several months with Atmel engineers to prepare and submit the support for this new SoC to the mainline Linux kernel. We have actually submitted the patches on September, 11th, almost a month before the official release of the new chip! This means that most of the support for this new SoC will already be part of the upcoming 3.18 kernel release. Meanwhile, it is already possible to test it out by using the linux-next repository.

There are however a few pieces missing pieces to support all aspects of the chip:

  • A few patches are needed to get proper NAND flash controller support.
  • The DMA controller is brand new in this SAMA5D4 SoC, and the DMA controller driver has not yet been merged, even though the patches have been posted a long time ago, and are currently in their sixth iteration.
  • Display support, through a DRM/KMS driver, is also being reviewed. The driver, written by Bootlin engineer Boris Brezillon, was initially designed for the sam9x5 and sam5d3, but will be compatible with sama5d4 as well. The patch series is currently in its seventh iteration.

The last big missing part is support for non-secure mode: for the moment, the system always runs in secure mode. Running the kernel in non-secure mode will require some more work but an initial version will probably be pushed during the next development cycle.

Besides this work on SAMA5D4 support ahead of its public release, Bootlin is also doing a lot of maintenance work on all the Atmel ARM platforms in the Linux kernel: migration to the Device Tree, to the clock framework, to several other new subsystems, etc. See the summary of our kernel contributions to 3.16, 3.15 and 3.14.

Through this work, the Bootlin engineering team has a very deep knowledge of the Linux support for Atmel ARM processors. Do not hesitate to contact us if you need help to bring up the bootloader or kernel on your custom Atmel ARM platform! It is also worth mentioning that Free-Electrons is part of the Atmel partner ecosystem.

2014 Q3 newsletter

Bootlin is happy to share some news about the latest training and contribution activities of the company.

Kernel contributions

Since our last newsletter, our engineering team continued to make significant contributions to the Linux kernel, especially in the area of supporting ARM processors and platforms:

  • 218 patches from Bootlin were merged into Linux 3.15, making Bootlin the 12th contributing company for this release by number of patches. See our blog post.
  • 388 patches from Bootlin were merged into Linux 3.16, making Bootlin the 7th contributing company for this release, by number of patches. See our blog post.
  • For the upcoming 3.17 release, we already have 146 patches merged, and we have a lot more work being done for future kernel releases.

The major areas of our contributions were:

  • The addition of an ubiblk driver, which allows traditional block filesystems to be used on top of UBI devices, and therefore on NAND flash storage. Only read-only support is available, but it already allows to make use of the super efficient SquashFS filesystem on top of NAND flash in a safe way.
  • Another major addition is support for the new Marvell Armada 375 and Armada 38x processors. In just two releases (3.15 and 3.16) we almost pushed entire support for these new processors. The network driver for Armada 375 is one missing piece, coming in 3.17.
  • Our maintenance work on the Atmel AT91 and SAMA5 processors has continued, with more conversion to the Device Tree, the common clock framework, and other modern kernel mechanisms. We have also developed the DRM/KMS (graphics) driver for the SAMA5D3 SoC, which has already been posted and should hopefully be merged soon.
  • Our work to support the Marvell Berlin processor has started to be merged in 3.16. This processor is used in various TVs, set-top boxes or devices like the Google Chromecast. Basic support was merged including Device Trees, clock drivers, pin-muxing driver, GPIO and SDHCI support. AHCI support will be in 3.17, and USB and network support should be in 3.18.
  • Additional work was done on support for Allwinner ARM SoCs, especially the A31 processor: SPI and I2C support, drivers for the P2WI bus and the PRCM controller, and support for USB.

We now have broad experience in writing kernel drivers and getting code merged into the mainline tree. Do not hesitate to contact us if you need help to develop Linux kernel drivers, or to support a new board or processor.

Buildroot contributions

Our involvement into the Buildroot project, a popular embedded Linux build system, is going on. We have merged 159 patches in the 2014.05 release of the project (total of 1293 patches), and 129 patches in the 2014.08 release of the project (total of 1353 patches). Moreover, our engineer Thomas Petazzoni is regularly an interim maintainer of the project, when the official maintainer Peter Korsgaard is not available. Some of the major features we contributed: major improvements to Python 3 support, addition of EFI bootloaders, addition of support for the Musl C library.

Regular embedded Linux projects

Of course, we also conducted embedded Linux development and boot time optimization projects for various embedded system makers, with less visible impact on community projects. However, we will try to share generic technical experience from such projects through future blog posts.

New training course: Yocto Project and OpenEmbedded

A large number of embedded Linux projects use embedded Linux build systems to integrate the various software components of the system into a working root filesystem image. Among the solutions available to achieve this, the Yocto Project and OpenEmbedded are very popular.

We have therefore launched a new 3 day Yocto Project and OpenEmbedded training course to help engineers and companies who are using, or are interested in using these solutions for their embedded Linux projects. Starting from the basics of understanding the core principles of Yocto, the training course goes into the details of writing package recipes, integrating support for a board into Yocto, creating custom images, and more.

The detailed agenda of the training course is available. You can order this training course at your location, or participate to the first public session organized on November 18-20 in France.

Embedded Linux training course updated

The embedded Linux ecosystem is evolving very quickly, and therefore we are continuously updating our training courses to match the latest developments. As part of this effort, we have recently conducted a major update to our Embedded Linux course: the hardware platform used for the practical labs has been changed to the popular and very interesting Atmel Xplained SAMA5D3, and many practical labs have been improved to provide a more useful learning experience. See our blog post for more details.

Mailing list for training participants

We have launched a new service for the participants to our training sessions: a mailing list dedicated to them, and through which they can ask additional questions after the course, share their experience, get in touch with other training participants and Bootlin engineers. Of course, all Bootlin engineers are on the mailing list and participate to the discussions. Another useful service offered by our training courses!

This resource is no longer available, but participants to our training sessions are still welcome to contact us by e-mail.

Conferences: ELC, ELCE, Kernel Recipes

The Bootlin engineering team will participate to the Embedded Linux Conference Europe and Linux Plumbers, next month in Düsseldorf, Germany. Several Bootlin engineers will also be giving talks during ELCE:

In addition, Thomas will participate to the Buildroot Developers Day, taking place right before the Embedded Linux Conference Europe in Düsseldorf.

See also our blog post about ELCE for more details.

Maxime Ripard and Michael Opdenacker will participate to the Kernel Recipes 2014 conference, on September 25-26 in Paris. Maxime will be giving his Allwinner kernel talk at this conference. See our blog post for more details.

Last but not least, we have recently published the videos of a number of talks from the previous Embedded Linux Conference, held earlier this year in San Jose. A lot of interesting material about embedded Linux! Check out our blog post for more details.

Upcoming training sessions

We have a number of public training sessions dates, with seats available:

Sessions and dates

Bootlin at Kernel Recipes 2014

Kernel RecipesThe Kernel Recipes conference is holding its third edition next week in Paris, on September 25th and 26th. With speakers like Greg Kroah-Hartmann, Hans Peter Anvin, Martin Peres, Hans Verkuil or Jean Delvare and many others, it is going to be a very interesting kernel-oriented conference.

Bootlin will participate to this conference, as our engineer Maxime Ripard will give a talk about Supporting a new ARM platform: the Allwinner example, and Maxime will be attending the event on both days.

Also, Bootlin’sCEO Michael Opdenacker will be attending the conference as well.

A good opportunity to meet Bootlin folks, and discuss business or career opportunities! We are always interested in getting to know more engineers with embedded Linux or Linux kernel knowledge to join our engineering team, so do not hesitate to meet us during the conference, or contact us ahead of time to plan a discussion. If you don’t have a seat yet, unfortunately the conference is fully booked, but meeting in the area is possible too.

Bootlin at the Embedded Linux Conference Europe

DüsseldorfThe Embedded Linux Conference Europe will take place on October 13-15 in Düsseldorf, Germany. As usual, a large part of the Bootlin engineering team will participate to the conference, with no less than 7 engineers: Alexandre Belloni, Boris Brezillon, Grégory Clement, Michael Opdenacker, Thomas Petazzoni, Maxime Ripard and Antoine Ténart.

Several of our talk proposals have been accepted, so we’ll be presenting about the following topics:

In addition to this participation to the Embedded Linux Conference Europe:

  • Many of us will also participate to the Linux Plumbers conference, on October 15-17. It’s another great opportunity to talk about topics around real-time, power management, storage, multimedia, and more.
  • Thomas Petazzoni will participate to the next Buildroot Developers Meeting.

As usual, we’re looking forward to this event! Do not hesitate to get in touch with us if you’re interested in meeting us during these events for specific discussions.

Linux 3.16 released, Bootlin 7th contributing company

Linus Torvalds has released the 3.16 kernel a few weeks ago. Unfortunately, the KernelNewbies LinuxChanges page has not been updated, but LWN.net summaries of the merge window (part 1, part 2 and final part) give a good summary of the important changes available in Linux 3.16.

On Bootlin’sside, 3.16 has been our most active kernel cycle ever: we have merged 388 patches in this cycle, making Bootlin the 7th company contributing to the Linux kernel by number of patches according to the statistics. Bootlin is ranked right after Texas Instruments, and before Novell, Renesas or Google. (Note that the statistics rank Bootlin as 9th, but this includes the “Unknown” and “Hobbyists” categories which are not companies). This strong participation clearly shows Bootlin’sability to get code merged in the mainline Linux kernel, as we’ve progressively done since kernel 3.6 over the last two years.

We are therefore available to help companies willing to add support for their hardware (processor, system-on-chip, module, or board) to the mainline Linux kernel. Do not hesitate to contact to get the discussion started.

Our major contributions have again been focused on the support of various ARM processor families:

  • On the Atmel SoC family
    • Conversion of the SAM9RL processor to the Device Tree. Done by Alexandre Belloni.
    • Huge cleanup of ADC/touchscreen handling: improvements in the IIO at91_adc driver to support more SoC families, and conversions of several Atmel platforms to use this driver, and then finally removal of the old atmel_tsadcc driver. Done by Alexandre Belloni.
    • Numerous fixes to the clock handling on various SoCs, following their conversion to the Common Clock Framework. Done by Alexandre Belloni.
    • Conversion of the SAM9RL, SAM9x5 and SAM9n12 SoCs to the Common Clock Framework. Done by Boris Brezillon.
    • Boris Brezillon is now one of the official maintainers for AT91 clock support.
  • On the Allwinner SoC family
    • Addition of PWM support to sun4i and sun7i. Done by Alexandre Belloni.
    • Addition of SMBus support to the regmap subsystem. This was needed to support the P2WI bus of Allwinner A31. Done by Boris Brezillon.
    • New I2C driver for the P2WI bus of Allwinner A31, used to communicate with the PMIC. Done by Boris Brezillon.
    • Improvements to the Allwinner pinctrl driver needed to support the P2WI bus. Done by Boris Brezillon.
    • Addition of a driver for the PRCM (Power, Reset and Clock Management) unit of the Allwinner A31. Done by Boris Brezillon.
    • Numerous cleanups of the pinctrl driver for Allwinner. Done by Maxime Ripard.
    • Addition of the ARM PMU description in the Device Tree of Allwinner platforms. Done by Maxime Ripard.
    • Add USB support for Allwinner A31. Done by Maxime Ripard, with some help from Boris Brezillon.
    • Various improvements to Allwinner clock drivers. Done by Maxime Ripard.
  • On the Marvell Berlin SoC family
    • Addition of basic Device Tree descriptions for several Marvell Berlin processors and boards. Done by Antoine Ténart.
    • Addition of clock drivers and DT clock descriptions of the Marvell Berlin processors. Done by Alexandre Belloni.
    • Addition of the pinctrl drivers for the Marvell Berlin processors. Done by Antoine Ténart.
    • Enabling of SDHCI and GPIO support on Marvell Berlin. Done by Antoine Ténart.
  • On the Marvell EBU SoC family
    • Addition of watchdog support for Armada 375 and Armada 38x, which required some changes to the existing watchdog driver. Done by Ezequiel Garcia.
    • Addition of thermal support for Armada 375 and Armada 38x, which required some changes in the existing armada_thermal driver. Done by Ezequiel Garcia.
    • Improvements of the pxa3xx_nand driver used for NAND support on Armada 370/375/38x/XP to use the newly introduced ECC strength and step size Device Tree bindings, which allows from the Device Tree to override the ECC constraints described by ONFI, when needed to match the bootloader constraints. Done by Ezequiel Garcia.
    • Addition of a generic software TSO (TCP Segmentation Offload) layer, and the corresponding changes to enable this feature in the mv643xx_eth and mvneta network drivers. This gives a huge performance boost in transmit operations! Done by Ezequiel Garcia.
    • SMP support for Armada 375 and Armada 38x has been added. Done by Grégory Clement.
    • cpuidle support for Armada XP has been added. Done by Grégory Clement.
    • USB support (USB2 and USB3) for Armada 375 and Armada 38x has been added. Done by Grégory Clement.
    • Hardware I/O coherency support for Armada 375 and Armada 38x. Done by Thomas Petazzoni.
    • Enabling of the SDHCI and AHCI interfaces on Armada 38x. Done by Thomas Petazzoni.
    • Major clean-up of Marvell Orion5x support. This is an older ARMv5 family of processors from Marvell, having a lot of similarities with Kirkwood and more recent Armada. This cleanup include many Device Tree conversions, up to the point where a few Marvell Orion5x platforms can now be fully described using a Device Tree, with no board file. Done by Thomas Petazzoni.
    • Addition of a new Device Tree binding for fixed network links, i.e links that do not use a MDIO-controlled PHY. This involved both some generic PHY layer improvements, and corresponding changes in the Marvell-specific mvneta network driver. Done by Thomas Petazzoni.
    • Addition of a work-around for a relatively complex PCIe/L2 errata affecting Armada 375/38x, which fixes heavy PCIe traffic when the system is running with hardware I/O coherency enabled. Done by Thomas Petazzoni.

Here is the complete list of patches from Bootlin merged into the 3.16 kernel:

Marvell publishes the datasheet of the Armada XP processor

thumb-armada-xpA bit more than a month after publishing the datasheet of the Armada 370 processor, Marvell has now released a similar datasheet for the more powerful Armada XP processor. The datasheet is available as a PDF document, with no registration, at http://www.marvell.com/embedded-processors/armada-xp/assets/ARMADA-XP-Functional-SpecDatasheet.pdf, with a link to it clearly visible on the Armada XP product page.

As most of our readers probably know, Bootlin has been working and continues to work significantly on the Linux kernel support for Marvell processors. Thanks to this work done for more than two years now, the mainline Linux kernel has pretty good support for the Armada XP processor. This processor is a nice monster: up to 4 cores (PJ4B cores, which are roughly equivalent to Cortex-A9 but with LPAE support), up to 10 PCIe interfaces, multiple SATA interfaces, up to four Gigabit network interfaces, and many, many other things (XOR engine, cryptographic engine, etc.). Many of the processor features are already supported in mainline, and lately we’ve been focusing on power management features: cpuidle support for Armada XP will be part of 3.16, cpufreq support will either be part of 3.17 or 3.18, and suspend/resume should hopefully be part of 3.18.

The Armada XP processor is used in publicly available products:

At Bootlin, we are again really happy to see Marvell opening this datasheet, as it will allow all community developers to further improve support for this processor in the Linux kernel, but also in other open-source projects.