From owner-freebsd-arch@FreeBSD.ORG Fri May 14 13:16:09 2010 Return-Path: Delivered-To: freebsd-arch@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id E3BE91065677 for ; Fri, 14 May 2010 13:16:09 +0000 (UTC) (envelope-from raj@semihalf.com) Received: from smtp.semihalf.com (smtp.semihalf.com [213.17.239.109]) by mx1.freebsd.org (Postfix) with ESMTP id 875248FC29 for ; Fri, 14 May 2010 13:16:09 +0000 (UTC) Received: from localhost (unknown [213.17.239.109]) by smtp.semihalf.com (Postfix) with ESMTP id 7FDDFC42D8; Fri, 14 May 2010 15:01:33 +0200 (CEST) X-Virus-Scanned: by amavisd-new at semihalf.com Received: from smtp.semihalf.com ([213.17.239.109]) by localhost (smtp.semihalf.com [213.17.239.109]) (amavisd-new, port 10024) with ESMTP id 2MC55HCRvLtm; Fri, 14 May 2010 15:01:32 +0200 (CEST) Received: from [192.168.14.120] (unknown [24.114.252.238]) by smtp.semihalf.com (Postfix) with ESMTPSA id B96C2C42D5; Fri, 14 May 2010 15:01:31 +0200 (CEST) Mime-Version: 1.0 (Apple Message framework v1078) Content-Type: text/plain; charset=utf-8 From: Rafal Jaworowski In-Reply-To: <20100514.064409.634347869525783787.imp@bsdimp.com> Date: Fri, 14 May 2010 14:57:03 +0200 Content-Transfer-Encoding: quoted-printable Message-Id: <9C502882-2DF8-42F7-8E97-B88A386E36E9@semihalf.com> References: <4BE98FB5.3060906@gmail.com> <20100514020055.GB89230@duncan.reilly.home> <4BECEE31.3060004@gmail.com> <20100514.064409.634347869525783787.imp@bsdimp.com> To: "M. Warner Losh" X-Mailer: Apple Mail (2.1078) Cc: phcoder@gmail.com, freebsd-arch@freebsd.org, grub-devel@gnu.org Subject: Re: [RFC] Multiboot2 drafting X-BeenThere: freebsd-arch@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussion related to FreeBSD architecture List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 14 May 2010 13:16:10 -0000 On 2010-05-14, at 14:44, M. Warner Losh wrote: > In message: <4BECEE31.3060004@gmail.com> > Vladimir '=CF=86-coder/phcoder' Serbinenko = 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. >=20 > 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... >=20 > 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