From mboxrd@z Thu Jan 1 00:00:00 1970 From: marc_gonzalez@sigmadesigns.com (Marc Gonzalez) Date: Fri, 22 Jan 2016 17:37:35 +0100 Subject: [RFC PATCH v3] irqchip: Add support for Tango interrupt controller In-Reply-To: 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> Message-ID: <56A25ACF.5040205@sigmadesigns.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 22/01/2016 17:35, M?ns Rullg?rd wrote: > Marc Gonzalez writes: > >> On 20/01/2016 19:09, M?ns Rullg?rd wrote: >> >>> Marc Gonzalez writes: >>> >>>> On 20/01/2016 17:38, M?ns Rullg?rd wrote: >>>> >>>>> Marc Gonzalez writes: >>>>> >>>>>> On 20/01/2016 17:25, M?ns Rullg?rd wrote: >>>>>> >>>>>>> Marc Zyngier writes: >>>>>>> >>>>>>>> On 20/01/16 16:10, M?ns Rullg?rd 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?