From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756688AbbKEJfx (ORCPT ); Thu, 5 Nov 2015 04:35:53 -0500 Received: from foss.arm.com ([217.140.101.70]:36181 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756585AbbKEJfu (ORCPT ); Thu, 5 Nov 2015 04:35:50 -0500 Message-ID: <563B22F1.901@arm.com> Date: Thu, 05 Nov 2015 09:35:45 +0000 From: Marc Zyngier Organization: ARM Ltd User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Icedove/31.7.0 MIME-Version: 1.0 To: Gabriele Paoloni , "majun (F)" , Thomas Gleixner , Jiang Liu , Jason Cooper CC: "linux-arm-kernel@lists.infradead.org" , "linux-pci@vger.kernel.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH RFC 7/7] irqchip: [Example] dummy wired interrupt/MSI bridge driver References: <1444923568-17413-1-git-send-email-marc.zyngier@arm.com> <1444923568-17413-8-git-send-email-marc.zyngier@arm.com> <5639BB10.1090108@huawei.com> <5639C9F9.2010704@arm.com> In-Reply-To: Content-Type: text/plain; charset=gbk Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 05/11/15 08:25, Gabriele Paoloni wrote: > Hi Marc > >> -----Original Message----- >> From: linux-pci-owner@vger.kernel.org [mailto:linux-pci-owner@vger.kernel.org] >> On Behalf Of Marc Zyngier >> Sent: 04 November 2015 09:04 >> To: majun (F); Thomas Gleixner; Jiang Liu; Jason Cooper >> Cc: linux-arm-kernel@lists.infradead.org; linux-pci@vger.kernel.org; linux- >> kernel@vger.kernel.org >> Subject: Re: [PATCH RFC 7/7] irqchip: [Example] dummy wired interrupt/MSI >> bridge driver >> >> On 04/11/15 08:00, majun (F) wrote: [...] >>> I think,for a interrupt controller, msichip driver initialization maybe is >> too late >>> for some devices which connect to this irqchip if we use >> module_platform_driver. >> >> That's a consequence of this design. This is why I insisted on the fact >> that this is currently avoided by using deferred probe in drivers, and > > Mmm using te deferred probe would mean to rework all the drivers of the > potential devices connected to mbi-gen...would that be sustainable/acceptable? I'm tempted to reply "Not my problem". Or rather, not a problem I'm trying to solve right now (or any time soon). I'm pretty sure that sprinkling -EPROBE_DEFER on all possible drivers will result in a resounding NAK, which is is why I suggested that someone with a vested interest dedicates some quality time helping those who are trying to solve this issue for good. >> that it should be solved by having a probe order. Either way, this is >> not something that we can solve at that level (see the multiple proposal >> for this on the various lists). > > Could you point me to the relevant discussions for this...? Google is, as always, your dearest friend. But here you go: - LWN has some quality coverage of the KS discussions (assuming you're a subscriber, otherwise you'll have to wait for another week): http://lwn.net/Articles/662820/ - There is also Tomeu Vizoso's series, which itself builds upon other previous attempts at solving this: https://lwn.net/Articles/658690/ Thanks, M. -- Jazz is not dead. It just smells funny...