Hi,

For this newsletter, I'm happy to welcome another contributor: Ludovic Desroches who wrote about a topic that he likes: Buildroot! By the way, don't hesitate to send us feedback or ideas about news that you would like to see highlighted.

Table of contents:

Linux4SAM demo version 5.2

At the end of February, we released the Linux4SAM version 5.2 which embeds several enhancements on all the components. It's the second release in two months as we wanted to update you as soon as possible with our latest developments. The main added features are:

  • Hardware Video decoder on SAMA5D4 with an update of the demo package to catch up on other SoCs and the updated Linux solution components;
  • Atmel WILC1000 WIFI driver and firmware included;
  • Support for new SAMA5D2 Ultra Low Power mode (ULP1).

And you can see the various Kernel enhancements in relation with each tag that we release by browsing the Linux4SAM kernel page tag list:
http://www.at91.com/linux4sam/bin/view/Linux4SAM/LinuxKernel#Tags

Now for all SAMA5 chips, you can choose 4 different screen options and 2 different boot media. That gives you 24 demo packages to choose from.
But by selecting the board first, in the left hand column, you can easily access the archive that best suits your needs.

As an example, you can access the SAMA5D2 demo table at:
http://www.at91.com/linux4sam/bin/view/Linux4SAM/Sama5d2XplainedMainPage#Demo

Removal of Buildroot git tree on Linux4SAM

As announced earlier, it is time to remove the old copy of the Buildroot git tree hosted on http://github.com/linux4sam. All the boards supported in Buildroot-at91 are also supported by the official Buildroot.

Latest enhancements will be available only on the official Buildroot repository.

Ludovic has recently sent a set of patches to improve the support of Xplained boards:
http://lists.busybox.net/pipermail/buildroot/2016-March/156981.html

Thanks to the reactivity and friendliness of the Buildroot community, the patch have already been merged in the master branch of the Buildroot repository.

These patches allow to build the latest linux4sam_5.2 components:
at91bootstrap, u-boot, linux and a basic rootfs (if you want to add extra packages, run make menuconfig and go to the 'Target packages' menu). Do not forget to read the board/atmel/readme.txt file to get explanations about how to flash NAND memory or how to create a SD card with these components.

Update of the Poky-atmel SDK

It's always convenient to simply extract a Software Development Kit (SDK) from an archive on the development host, write a simple application and load it on a pre-flashed embedded Linux board. This is what we propose with our latest poky-atmel SDK. Not only it gives access to the very same libraries as the ones already installed in the board root filesystem but it packages everything in an easily installable archive and gives the instructions to use it. After it's deployed, you can simply trigger your usual project builder like Make, QMake, or any autotools-based cross-building process.

The Yocto Project allowed us to build this SDK and provide this convenient setup. The documentation is also comprehensive both for the build of this SDK as well as the use of it.

All the libraries installed in our QT5 demo are also available in the SDK: from a QT project to an application using SSL, you'll find many components ready to help you with your development.

So, check our SDK table and the few links that we propose on the Software tools Linux4SAM page.

Linux demos at Embedded World

Don't forget to go and check the blog post about SAMA5 demos that we presented at Embedded World 2016: http://blog.atmel.com/2016/03/07/3-iot-demos-that-highlight-atmels-sama5/

Activity on the linux-arm-kernel mailing-list

Here is a brief summary of the most important discussions that happened around the Atmel | Smart ARM-based processors (aka AT91) during February:

  • The big rework of the PMC driver done by Alexandre is now included in the upcoming 4.6 kernel. In his words, "This [ rework ] is a cleanup that properly separate drivers needing to access the PMC ([ Power Management ] and USB) from the clock driver by exposing the PMC as a syscon ( ed. note: syscon allows to access a common register set from different IPs with automatic locking and value update mechanism done by regmap )".
    This rework also allows to fix a previous bug in preempt-rt kernel flavor;
  • Important fixes were sent by Ludovic for the USART on SAMA5D2 and by Cyrille for SHA on SAMA5D2 and SAMA5D4;
  • The discussion is still going on with QSPI and ULP1 topics. These detailed and deeply technical debates allow us to gain competence and strengthen our code.
  • The QSPI code is also being deployed on the U-Boot bootloader and is already sent on this project's mailing-list:
    sf: fix support of QSPI memories and controllers. Unfortunately, it is delayed there by a complete re-factor of the spi-nor subsystem;
  • The PMIC ACT8945A that embeds a regulator and a Li/Po battery charger now has its driver in mainline under the control of a MFD (Multi-Function Device). This code, contributed by Wenyou is used on our latest SAMA5D2 Xplained board.

We hope that the content is interesting for you and don't hesitate to contact us for any remark about this newsletter.
Bye,

Nicolas Ferre, Ludovic Desroches and the whole OS team