[RFC] Multiboot2 drafting

[Rafal Jaworowski]

On 2010-05-14, at 14:44, M. Warner Losh wrote:

> In message: <4BECEE31.3060004 at gmail.com>
>            Vladimir 'φ-coder/phcoder' Serbinenko <phcoder at gmail.com> writes:
> : Yes and No. multiboot2 describes some aspects of the host system
> : hardware but I've never heard of device trees outside of IEEE1275 or
> : xnu, where it's probably a historical leftover.
> 
> It is far from a historical left-over.  Linux critically depends on
> the boot loader on PowerPC to provide it with a tree of devices that
> it cannot otherwise probe.  On other architectures, it is becoming an
> optional way to specify the device tree as well.  There are many
> different implementations of this, since primarily it is just data and
> boot loaders are good at providing binary blobs to the kernel...
> 
> In addition, Rafal Jawarski has ported this technology to FreeBSD.
> He's presenting a paper on it today at BSDcan:
> 	http://www.bsdcan.org/2010/schedule/events/171.en.html
> I've reviewed the work, and it goes a long way towards making some of
> the more stupid and repetitive parts of doing a port to a new embedded
> architecture easy.

Yes, more on this can be found at the wiki page http://wiki.freebsd.org/FlattenedDeviceTree, there will also be a paper available as a post-conference material about this project.

As of now we have flattened device tree support on 2 PowerPC platforms and 6 ARM-based systems already completed.

Rafal