[PATCH 03/11] devicetree: bindings: Document qcom,kpss-acc

[Kumar Gala]

On Nov 5, 2013, at 11:44 AM, Stephen Boyd wrote:

> On 11/05/13 09:13, Kumar Gala wrote:
>> On Nov 1, 2013, at 5:08 PM, Stephen Boyd wrote:
>> 
>>> diff --git a/Documentation/devicetree/bindings/arm/msm/qcom,kpss-acc.txt b/Documentation/devicetree/bindings/arm/msm/qcom,kpss-acc.txt
>>> new file mode 100644
>>> index 0000000..ed4a9c8
>>> --- /dev/null
>>> +++ b/Documentation/devicetree/bindings/arm/msm/qcom,kpss-acc.txt
>>> @@ -0,0 +1,21 @@
>>> +* Krait Processor Sub-system (KPSS) Application Clock Controller (ACC)
>>> +
>>> +The KPSS ACC provides clock, power domain, and reset control to a Krait CPU.
>>> +There is one ACC register region per CPU within the KPSS remaped region as
>>> +well as an alias register region that remaps accesses to the ACC associated
>>> +with the CPU accessing the region.
>>> +
>>> +Required Properties:
>>> +
>>> +- compatible : Shall contain "qcom,kpss-acc-v1" or "qcom,kpss-acc-v2".
>>> +- reg: Specifies the base address and size of the banked register region.
>>> +- cpu-offset : per-cpu offset used when the device is accessed without the
>>> +		CPU remapping facilities.
>>> +		The offset is cpu-offset + (0x10000 * cpu-nr).
>>> +
>>> +Example:
>>> +
>>> +	clock-controller at 2008000 {
>>> +		compatible = "qcom,kpss-acc-v2";
>>> +		reg = <0x02008000 0x1000>;
>>> +	};
>>> -- 
>> I don't get the cpu-offset business, shouldn't this just be:
>> 	reg = <0x02008000 0x1000>, <0x02018000 0x1000>, <0x02028000 0x1000>, <0x02038000 0x1000>;
>> 
> 
> (Sorry I forgot to add the cpu-offset to the example.)
> 
> Your reg property is one way to do it. I was following the example of
> the GIC binding which just specifies the alias region of the GIC's CPU
> registers and then has a cpu-offset property to describe how to reach a
> specific CPU's region.

Even in the gic's case I think we should have the reg property cover the memory map.

- k

-- 
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