Re: [PATCH v2 02/18] dt-bindings: timer: sp804: add timer-width property

Rob Herring
2016-03-17T19:00:48Z

On Thu, Mar 17, 2016 at 1:06 PM, Robin Murphy <robin.murphy@arm.com> wrote:
> Hi Rob,
>
> On 17/03/16 17:09, Rob Herring wrote:
>>
>> On Wed, Mar 09, 2016 at 11:24:04AM +0100, Neil Armstrong wrote:
>>>
>>> Add timer-width optional property to specify a different vendor
>>> specific timer counter bit-width.
>>>
>>> Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
>>> ---
>>> Documentation/devicetree/bindings/timer/arm,sp804.txt | 2 ++
>>> 1 file changed, 2 insertions(+)
>>>
>>> diff --git a/Documentation/devicetree/bindings/timer/arm,sp804.txt
>>> b/Documentation/devicetree/bindings/timer/arm,sp804.txt
>>> index 5cd8eee7..141e143 100644
>>> --- a/Documentation/devicetree/bindings/timer/arm,sp804.txt
>>> +++ b/Documentation/devicetree/bindings/timer/arm,sp804.txt
>>> @@ -17,6 +17,8 @@ Optional properties:
>>> - arm,sp804-has-irq = <#>: In the case of only 1 timer irq line
>>> connected, this
>>> specifies if the irq connection is for timer 1 or timer 2. A
>>> value of 1
>>> or 2 should be used.
>>> +- arm,timer-width: Should contain the width in number of bits of the
>>> counter,
>>> + is considered by default 32 but can be changed for vendor
>>> variants.
>>
>>
>> That would not be an SP804 nor would the vendor be ARM in that case. So
>> add a new compatible string for the vendor that decided to hack up ARM's
>> IP block.
>
>
> By all accounts this is some ancient reference design[1] which later evolved
> _into_ the SP804, so that vendor would probably still be ARM ;)

Right.

> A separate compatible string would indeed make more sense, though. Both
> semantically and in terms of letting the driver account for the differences
> automatically.
>
> Robin.
>
> [1]:http://infocenter.arm.com/help/topic/com.arm.doc.ddi0170a/I350250.html

Humm, same as integrator timers perhaps?

Rob

>
>>
>> Rob
>>
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>>
>