About the Kernel Consolidation Work Group

The core working group deals with core engineering, typically generic kernel engineering that benefits all SoCs. For example, kernel consolidation via such mechanisms as device trees.


Kernel Consolidation

This includes:

  • Device tree support
  • Generalised (plugable) support for timers and interrupt controllers

Existing Work

There is a bunch of stuff already happening, this section lists the known work

  • Owner



    Grant Likely

    OMAP, QEMU: Versatile 926

    Unifying PowerPC, sparc and microblaze DT code to a generic layer (drivers/of/). Overall maintainer of the generic device-tree code. Updating the driver interface for DT-compatible devices & drivers. Some driver work for DT on ARM.

    Robert Herring (Freescale)


    Provided some basic iMX platform support for the DT tree

    Jeremy Kerr

    iMX51, QEMU: Versatile 926

    Early boot & platform setup support for DT on ARM, based on Grant's generic DT tree. Some driver support for iMX & versatile platforms. New generic clock API, based on proposals from PowerPC.

    Lorenzo Pieralisi


    Looking at supporting device tree on the ARM versatile platform

Most of Jeremy's current work is on the ubuntu wiki: ARMDeviceTrees.

Some milestones so far:

  • DT support for qemu ARM code
  • DT-enabled kernel booting on versatile on qemu
  • Basic driver probing on versatile on qemu
  • DT-enabled kernel booting on iMX51
  • Embedded-DTB kernel support, enabling DT boot on bootloaders with no DT support.

Proposed Experiments

Moving to flattened device trees appears to make sense, this section proposes experiments to prove that this is indeed the case:

  • Experiment



    Convert a platform to device tree

    Kernel runs with little or no performance difference

    Run the same kernel on two platforms

    Kernel runs on both platforms

    Would be good to have radically different platforms, but assume same architecture

There is a blueprint to track all the existing hardcoded assumptions in the ARM kernel that need to be fixed https://blueprints.edge.launchpad.net/ubuntu/+spec/kernel-maverick-arm-single-zimage


A list of all meetings can be found on the Meetings page.

WorkingGroups/KernelConsolidation-orig (last modified 2010-06-28 14:40:53)