From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751835Ab1IUFTA (ORCPT ); Wed, 21 Sep 2011 01:19:00 -0400 Received: from gate.crashing.org ([63.228.1.57]:32865 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751557Ab1IUFS5 (ORCPT ); Wed, 21 Sep 2011 01:18:57 -0400 In-Reply-To: <20110920.224910.1996429830782124690.davem@davemloft.net> References: <1316550244-3655-1-git-send-email-robherring2@gmail.com> <20110920.224910.1996429830782124690.davem@davemloft.net> Mime-Version: 1.0 (Apple Message framework v753.1) Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed Message-Id: <15B014F7-0085-455D-A641-AA7ADFB68545@kernel.crashing.org> Cc: robherring2@gmail.com, dave.martin@linaro.org, linux@arm.linux.org.uk, devicetree-discuss@lists.ozlabs.org, linux-kernel@vger.kernel.org, rob.herring@calxeda.com, linux-arm-kernel@lists.infradead.org Content-Transfer-Encoding: 7bit From: Segher Boessenkool Subject: Re: [PATCH 0/3] GIC OF bindings Date: Wed, 21 Sep 2011 07:16:52 +0200 To: David Miller X-Mailer: Apple Mail (2.753.1) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > Just out of curiosity where does this "interrupt-parent" property > come from? > > On platforms I am familiar with, the parent path is walked to the root > and we stop at device nodes that have "interrupt-map" and > "interrupt-map-mask" properties. "interrupt-parent" is defined in the Open Firmware "interrupt mapping" recommended practice, the same place as "interrupt-map" etc. are. > The mechanism shown here seems overly simplistic and not able to > handle > the cases handled by existing OF property schemes in use for several > years on real systems. "interrupt-parent" is only meant to be used for the simple cases. It's quite handy there. It is also required in all "interrupt-controller" nodes that aren't the root of the interrupt tree. Segher