ELCE2014 U-Boot Mini Summit

NA = Needs Approval before publishing the name

From left to right: NA, Pavel Machek, Anatolij Gustschin, NA (?), NA (?) (red shirt), Marek Vasut, Hans De Goede, NA, Joe Hershberger, Michal Simek (white sweater), NA, NA, NA, Heiko Schocher, Stefan Roese (turquoise), Stefano Babic, Daniel Schwierzeck, Wolfgang Denk, Alexey Brodkin, Lukasz Majewski, Przemyslaw Marczak, Simon Glass, Tom Rini, Masahiro Yamada (front), Detlev Zundel, NA (?)

Date and Location

Monday, October 13th 2014, Düsseldorf. Room 6

The U-Boot mini summit will be part of the Embedded Linux Conference Europe, so a registration for that event is required to join. See the main ELCE pages for more info.

Agenda

Currently planned topics - schedule may still change in small ways.

A table for 30 people is reserved at the Füchschen restaurant in Düsseldorf for 20:00 so that we can continue the discussions over a beer or two.

Open Discussion

Topics of interest can be added here in the wiki directly

Abstracts

U-Boot for Tizen (Lukasz Majewski)

Utilization of u-boot bootloader at Samsung's Linux powered platforms has a long history. For Tizen 3.0 the reference devices for mobile profile (RD_PQ and Odroid U3/X2) are due to run with u-boot developed with open source philosophy applied. It means that the code was developed, reviewed and tested first in the open source and then reused in Tizen.

Introduced changes to mainline code were minimal and only necessary for assuring backward compatibility. In his presentation Lukasz will briefly cover history and future plans of u-boot development for Tizen (as e.g. ongoing work on single binary for Odroid U3 and M0), explain key aspects of persuading community to accept solutions tunned for mobile devices, present remarkable u-boot's war stories and give a handful of tips for successful cooperation with community.

U-Boot on Sunxi (Hans de Goede)

Hans would like to start a discussion on how to get (more) manufacturers engaged in upstreaming their work / working directly with upstream from day one.

His own experience in this comes from the Allwinner sunxi support, where Allwinner themselves are shipping quite an old u-boot version, which is not even fully functional as it gets chainloaded by a custom loader which sets up RAM first. Thanks to the work of various people in the community we've a fully functional U-Boot (replacing the custom loader) for sun4i, sun5i and sun7i. But we are still e.g. waiting for someone to get sun6i support in place.

ARC - new first class citizen in U-Boot (Alexey Brodkin)

U-Boot is a de-facto standard bootloader for Linux-driven embedded systems. It provides flexible means for loading kernel and if required image of filesystem from different media be it embedded non-volatile memory, attached storage or even network share. Linux kernel was ported to DesignWare ARC a while ago and starting from version 3.9 the port was accepted upstream. Now to enable real-life device booting on custom hardware decision was made to port U-Boot for ARC. This presentation unveils reasons to start the project, highlights milestones passed during porting process, touches some pitfalls and encourages more engineers and companies to use and contribute to U-Boot project.

Kbuild and Kconfig for U-Boot (Masahiro Yamada)

U-Boot has had big changes on its build system in the past year.

Kbuild and Kconfig provide us a lot of benefites; however there have been various hurdles to overcome for switching over to the new infrastructure. Porting had to be done carefully, step by step so as not to break any exisiting features and boards.

This talk will explain how the migration was done, why the current approach was chosen and what will happen in the next phase.

A Driver model for U-Boot (Simon Glass)

A long-standing limitation of U-Boot has been its ad-hoc device driver system. Introduced in 2014.04, U-Boot's new 'driver model' supports multiple peripheral controllers, hierarchical devices and device tree. In this session U-Boot's driver model will be described including design goals, architecture, benefits, test methodology and limitations. A short status update will be provided for the programme to convert U-Boot fully to driver model.

Power(full) framework based on Driver Model - discussion (Przemyslaw Marcak)

There are lots of various Power Management IC's in the Embedded Systems nowadays. Each can provide the same functionality, like a voltage regulators, chargers, signal switches and some more - which are usually driven in a device specific way.

Beside the battery state, the current PMIC framework provides registers read/write operations only. So the user is obligated to check the documentation and set a specific value of some register to change the state of any regulator.

To solve the problem with driving common functionality - the Driver Model can be used.

The aim of this discussion is to present author's conception about how to use the Driver Model, and get the feedback from the listeners to introduce a common and functional framework architecture.

Interested participants (sorted alphabetically)

Please add yourself to this list if you intend to come so we get an idea of the audience:

• Stefano Babic
• Alexey Brodkin
• Wolfgang Denk
• Dirk Eibach
• Simon Glass
• Hans de Goede
• Igor Grinberg
• Anatolij Gustschin
• Joe Hershberger
• Nobuhiro Iwamatsu
• Christian Jann
• Nikita Kiryanov
• Siva Durga Prasad Paladugu
• Tom Rini
• Stefan Roese
• Heiko Schocher
• Daniel Schwierzeck
• Michal Simek
• Marek Vasut
• Scott Wood
• Masahiro Yamada
• Detlev Zundel