[RFC PATCH 3/3] ARM: gic: add OF based initialization
Rob Herring
robherring2 at gmail.com
Wed Aug 10 14:30:00 EDT 2011
On 08/10/2011 03:08 AM, Marc Zyngier wrote:
> On 09/08/11 21:17, Rob Herring wrote:
>> From: Rob Herring <rob.herring at calxeda.com>
>>
>> This adds gic initialization using device tree data. An example device tree
>> binding looks like this:
>>
>> intc: interrupt-controller at fff11000 {
>> compatible = "arm,cortex-a9-gic";
>> #interrupt-cells = <1>;
>> interrupt-controller;
>> reg = <0xfff11000 0x1000>,
>> <0xfff10100 0x100>;
>> };
>
> I'm afraid I still object to this. PPIs are an important part of the
> GIC, and this binding totally ignores the per-cpu aspect.
BTW, we've already got 2 flavors of gic bindings in the dts files.
> How do you represent the connection between a CPU local timer and the
> GIC? Even worse, how to represent a device connected to only *one* of
> the CPUs? PPIs are difficult to represent on the Linux side. But we
> shouldn't ignore them in the DT binding.
>
Do you have an updated gic binding patchset based on your latest PPI
patch series?
This problem also extends to the TWD itself. How do we represent that?
Is it 1 node per core or 1 node total. Then is timer and watchdog in 1
node, or is it split to separate nodes?
Rob
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