From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753853AbcAVQjd (ORCPT ); Fri, 22 Jan 2016 11:39:33 -0500 Received: from unicorn.mansr.com ([81.2.72.234]:54816 "EHLO unicorn.mansr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752663AbcAVQjb convert rfc822-to-8bit (ORCPT ); Fri, 22 Jan 2016 11:39:31 -0500 From: =?iso-8859-1?Q?M=E5ns_Rullg=E5rd?= To: Marc Gonzalez Cc: Marc Zyngier , Thomas Gleixner , Jason Cooper , LKML , Linux ARM , Sebastian Frias Subject: Re: [RFC PATCH v3] irqchip: Add support for Tango interrupt controller References: <569CE0F2.1060507@sigmadesigns.com> <569D0B80.1010908@sigmadesigns.com> <569D165E.4060004@sigmadesigns.com> <569FAFF5.4090909@arm.com> <569FB471.8000909@arm.com> <569FB7A9.9080309@sigmadesigns.com> <569FB91D.9030704@sigmadesigns.com> <56A2518F.6060808@sigmadesigns.com> <56A25ACF.5040205@sigmadesigns.com> Date: Fri, 22 Jan 2016 16:39:30 +0000 In-Reply-To: <56A25ACF.5040205@sigmadesigns.com> (Marc Gonzalez's message of "Fri, 22 Jan 2016 17:37:35 +0100") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.5 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Marc Gonzalez writes: > On 22/01/2016 17:35, Måns Rullgård wrote: >> Marc Gonzalez writes: >> >>> On 20/01/2016 19:09, Måns Rullgård wrote: >>> >>>> Marc Gonzalez writes: >>>> >>>>> On 20/01/2016 17:38, Måns Rullgård wrote: >>>>> >>>>>> Marc Gonzalez writes: >>>>>> >>>>>>> On 20/01/2016 17:25, Måns Rullgård wrote: >>>>>>> >>>>>>>> Marc Zyngier writes: >>>>>>>> >>>>>>>>> On 20/01/16 16:10, Måns Rullgård wrote: >>>>>>>>> >>>>>>>>>> Marc Zyngier writes: >>>>>>>>>> >>>>>>>>>>>> + if (of_property_read_u32(node, "reg", &ctl)) >>>>>>>>>>>> + panic("%s: failed to get reg base", node->name); >>>>>>>>>>>> + >>>>>>>>>>>> + chip = kzalloc(sizeof(*chip), GFP_KERNEL); >>>>>>>>>>>> + chip->ctl = ctl; >>>>>>>>>>>> + chip->base = base; >>>>>>>>>> >>>>>>>>>> As I said before, this assumes the outer DT node uses a ranges >>>>>>>>>> property. Normally reg properties work the same whether they specify an >>>>>>>>>> offset within an outer "ranges" or have a full address directly. It >>>>>>>>>> would be easy enough to make this work with either, so I don't see any >>>>>>>>>> reason not to. >>>>>>>>> >>>>>>>>> Yup, that is a good point. I guess Marc can address this in the next >>>>>>>>> round, since we need a DT binding anyway. >>>>>>>> >>>>>>>> I'd suggest using of_address_to_resource() on both nodes and subtracting >>>>>>>> the start addresses returned. >>>>>>> >>>>>>> For my own reference, Marc Zyngier suggested: >>>>>>> "you should use of_iomap to map the child nodes, and not mess with >>>>>>> the parent one." >>>>>> >>>>>> That's going to get very messy since the generic irqchip code needs all >>>>>> the registers as offsets from a common base address. >>>>> >>>>> The two suggestions are over my head at the moment. >>>>> >>>>> Do you want to submit v4 and have Marc Z take a look? >>>> >>>> Done. If this isn't acceptable either, I'm out of ideas that don't end >>>> up being far uglier than anything suggested so far. >>> >>> With your latest patch, can I drop the ranges property? >> >> Why would you want to do that? > > I thought that was the whole point of the v4 improvement? The point was to make it work right *if* someone were to do that even though having it there better reflects what the hardware actually looks like. -- Måns Rullgård