From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932930AbcIAOsk (ORCPT ); Thu, 1 Sep 2016 10:48:40 -0400 Received: from foss.arm.com ([217.140.101.70]:60762 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753985AbcIAOsi (ORCPT ); Thu, 1 Sep 2016 10:48:38 -0400 Subject: Re: [Patch v3 03/11] irqchip: axi-intc: Add support for parent intc To: Zubair Lutfullah Kakakhel , monstr@monstr.eu, ralf@linux-mips.org, tglx@linutronix.de, jason@lakedaemon.net References: <1472661352-11983-1-git-send-email-Zubair.Kakakhel@imgtec.com> <1472661352-11983-4-git-send-email-Zubair.Kakakhel@imgtec.com> <57C70C71.3060603@arm.com> <81b5f75c-51b5-0482-50d1-f51c5687edbc@imgtec.com> <57C81BB5.3060807@arm.com> Cc: soren.brinkmann@xilinx.com, linux-kernel@vger.kernel.org, linux-mips@linux-mips.org, michal.simek@xilinx.com, netdev@vger.kernel.org From: Marc Zyngier Organization: ARM Ltd Message-ID: <57C83FB2.607@arm.com> Date: Thu, 1 Sep 2016 15:48:18 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Icedove/38.7.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/09/16 14:52, Zubair Lutfullah Kakakhel wrote: > Hi, [...] >> But that still doesn't address the case I had in mind, which is when you >> have *two* AXI-intc, one cascaded into the other. Is that something that >> could be built? You should at least make sure that there is a big fat >> warning if you don't want to support that case, because that will be >> hell to debug. > > Oo. I didn't think of that one. tbh, I'm not sure if that is currently supported > because this driver came out of arch/microblaze. And it didn't have any code that > looked supportive of chained interrupt handling. > > 'Technically', it should be possible to synthesize two daisy chained axi interrupt > controllers on an FPGA. But I don't see it being supported before. > > A warning would be nice. Any suggestions on the most suitable way? Check if you've already allocated a xintc_irqc. If so, abort the probing early... Thanks, M. -- Jazz is not dead. It just smells funny...