From mboxrd@z Thu Jan 1 00:00:00 1970 From: marc_gonzalez@sigmadesigns.com (Marc Gonzalez) Date: Wed, 20 Jan 2016 17:43:09 +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> Message-ID: <569FB91D.9030704@sigmadesigns.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org 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? Regards.