From mboxrd@z Thu Jan 1 00:00:00 1970 From: wmb@firmworks.com (Mitch Bradley) Date: Tue, 18 May 2010 21:25:38 -1000 Subject: Boot interface for device trees on ARM In-Reply-To: References: <201005181054.32325.jeremy.kerr@canonical.com> <201005181324.45701.jeremy.kerr@canonical.com> <20100518084954.GC25892@yookeroo> Message-ID: <4BF39272.7070909@firmworks.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Nicolas Pitre wrote: > ... > Exact. For example, on ARM the machine ID is also used to figure out > the MMU mapping needed to be able to simply be able to debug the very > early assembly boot stage when there isn't even a stack available. While > this info is stored in the machine record, it is actually > subarchitecture specific and already half-digested for easy usage by > that initial MMU setup. I just don't want to imagine what the > equivalent functionality with DT would look like. > > > Under what circumstances would the Linux startup code not have a stack - or not be able to set up one easily? From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mitch Bradley Subject: Re: Boot interface for device trees on ARM Date: Tue, 18 May 2010 21:25:38 -1000 Message-ID: <4BF39272.7070909@firmworks.com> References: <201005181054.32325.jeremy.kerr@canonical.com> <201005181324.45701.jeremy.kerr@canonical.com> <20100518084954.GC25892@yookeroo> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-arm-kernel-bounces@lists.infradead.org Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: Nicolas Pitre Cc: nicolas.pitre@canonical.com, Jeremy Kerr , devicetree-discuss@lists.ozlabs.org, linux-arm-kernel@lists.infradead.org, David Gibson List-Id: devicetree@vger.kernel.org Nicolas Pitre wrote: > ... > Exact. For example, on ARM the machine ID is also used to figure out > the MMU mapping needed to be able to simply be able to debug the very > early assembly boot stage when there isn't even a stack available. While > this info is stored in the machine record, it is actually > subarchitecture specific and already half-digested for easy usage by > that initial MMU setup. I just don't want to imagine what the > equivalent functionality with DT would look like. > > > Under what circumstances would the Linux startup code not have a stack - or not be able to set up one easily?