From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andres Salomon Date: Tue, 29 Jun 2010 15:03:24 +0000 Subject: Re: [PATCH 2/4] sparc: break out some prom device-tree building Message-Id: <20100629110324.2756cc02@debian> List-Id: References: <20100628215407.2017bf2f@debian> <20100628220037.5744c207@debian> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Grant Likely Cc: devicetree-discuss@lists.ozlabs.org, sparclinux@vger.kernel.org, x86@kernel.org, tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, cjb@laptop.org, Mitch Bradley , pgf@laptop.org, linux-kernel@vger.kernel.org, davem@davemloft.net, Benjamin Herrenschmidt On Tue, 29 Jun 2010 00:50:08 -0700 Grant Likely wrote: > On Mon, Jun 28, 2010 at 7:00 PM, Andres Salomon wrote: > > > > Stick code into drivers/of/pdt.c (Prom Device Tree) that other > > architectures with OpenFirmware resident in memory can make use of. > > > > Signed-off-by: Andres Salomon > > Hi Andres, > > The patch itself looks fine, but there are currently two methods for > extracting the device tree from open firmware; one in arch/powerpc > using the flattened format, and one in arch/sparc. I don't want to > end up maintaining both methods in drivers/of, and there has also some > discussions on moving the powerpc version into common code. I've been > thinking about using the powerpc approach to support ARM platforms > using both the flat tree and real OFW. > > Ben, what say you? Before I do anything I'd like to have your opinion. > So you're saying that you want ARM (and sparc, and OLPC) to generate a flat tree by calling into OFW? Sparc and OLPC have very similar mechanisms for getting device tree info from OFW, so it makes sense to share code between them. From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756447Ab0F2PDh (ORCPT ); Tue, 29 Jun 2010 11:03:37 -0400 Received: from LUNGE.MIT.EDU ([18.54.1.69]:35622 "EHLO lunge.queued.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756377Ab0F2PDf (ORCPT ); Tue, 29 Jun 2010 11:03:35 -0400 Date: Tue, 29 Jun 2010 11:03:24 -0400 From: Andres Salomon To: Grant Likely Cc: devicetree-discuss@lists.ozlabs.org, sparclinux@vger.kernel.org, x86@kernel.org, tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, cjb@laptop.org, Mitch Bradley , pgf@laptop.org, linux-kernel@vger.kernel.org, davem@davemloft.net, Benjamin Herrenschmidt Subject: Re: [PATCH 2/4] sparc: break out some prom device-tree building code out into drivers/of Message-ID: <20100629110324.2756cc02@debian> In-Reply-To: References: <20100628215407.2017bf2f@debian> <20100628220037.5744c207@debian> X-Mailer: Claws Mail 3.7.6 (GTK+ 2.20.1; i486-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 29 Jun 2010 00:50:08 -0700 Grant Likely wrote: > On Mon, Jun 28, 2010 at 7:00 PM, Andres Salomon wrote: > > > > Stick code into drivers/of/pdt.c (Prom Device Tree) that other > > architectures with OpenFirmware resident in memory can make use of. > > > > Signed-off-by: Andres Salomon > > Hi Andres, > > The patch itself looks fine, but there are currently two methods for > extracting the device tree from open firmware; one in arch/powerpc > using the flattened format, and one in arch/sparc. I don't want to > end up maintaining both methods in drivers/of, and there has also some > discussions on moving the powerpc version into common code. I've been > thinking about using the powerpc approach to support ARM platforms > using both the flat tree and real OFW. > > Ben, what say you? Before I do anything I'd like to have your opinion. > So you're saying that you want ARM (and sparc, and OLPC) to generate a flat tree by calling into OFW? Sparc and OLPC have very similar mechanisms for getting device tree info from OFW, so it makes sense to share code between them.