From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Sender: Grant Likely Date: Wed, 4 May 2011 10:05:02 -0600 From: Grant Likely To: Benjamin Herrenschmidt Subject: Re: [PATCH 4/6] dt: generalize irq_of_create_mapping() Message-ID: <20110504160502.GC3317@ponder.secretlab.ca> References: <20110428192227.8979.49181.stgit@ponder> <20110428200203.8979.3569.stgit@ponder> <1304387422.2513.301.camel@pasglop> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <1304387422.2513.301.camel@pasglop> Cc: Michal Simek , Sebastian Andrzej Siewior , x86@kernel.org, linux-kernel@vger.kernel.org, Ralf Baechle , hpa@zytor.com, Dirk Brandewie , Thomas Gleixner , linuxppc-dev@lists.ozlabs.org, devicetree-discuss@lists.ozlabs.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Tue, May 03, 2011 at 11:50:22AM +1000, Benjamin Herrenschmidt wrote: > On Thu, 2011-04-28 at 14:02 -0600, Grant Likely wrote: > > This patch creates a common implementation of irq_of_create_mapping() > > and factors out the interrupt domain translation code from powerpc to > > make it available for all architectures. > > I think you are going the wrong way around. > > First thing first, is to make the irq domain / mapping API generic > without the OF bits. > > IE. move the IRQ domain generically, get rid of irq_map by putting the > domain ptr & hw numbers in the irq desc/data etc... > > Then you can move over the OF specific bits which are optional and > orthogonal to a large extent. As discussed in my other reply, I disagree. There isn't an immediate need for the mapping interface in common code. It would be useful, sure, for some interrupt controllers, but for many of them irq_alloc_descs() and an irq_base value is all the functionality that is needed, and irq_host doesn't gain anything. The OF translation on the other hand is needed immediately by several architectures and are very much non-optional in that regard. g.