[PATCH v3 06/11] ARM: vexpress: use clocksource_of_init for sp804

Haojian Zhuang haojian.zhuang at linaro.org
Wed Mar 13 08:21:47 EDT 2013


On 13 March 2013 19:46, Pawel Moll <pawel.moll at arm.com> wrote:
> On Wed, 2013-03-13 at 11:42 +0000, Haojian Zhuang wrote:
>> > I love the possibility of removing the SP804 code from the VE machine
>> > (thanks for your work!), but I'd like to avoid it being replaced by
>> > cryptic properties in the tree.
>> >
>> > Now, to get this right: I'm not saying that there should be completly no
>> > OS-specific (but neutral) properties for the clocking system.
>> >
>> > I'm saying that in "my" (the VE) case, there are four, effectively
>> > identical timers (each pair sharing an interrupt though). Every single
>> > one of them is perfectly capable of serving as clocksource or
>> > clockevent. Therefore I believe the driver/framework/OS should make its
>> > own decision.
>> >
>> I can move those properties into dts file instead.
>
> I'm not sure I understand you here...
>
>> If clocksource uses alias to configure source or event. There's still a lot
>> of work. At least we need to split dual timer into two timer devices in DTS.
>
> My point is: at least for VE there is _no need_ for any alias or special
> property in the tree (DTS). All timers are equal. The system can (and
> should) pick any one it wants.
>
> Paweł
>
Do you mean that system wants to pick any one randomly? It's impossible.
Imagine that only TIMINT1 signal in sp804 is routed to interrupt controller.
Could system still pick any one it wants?

I think that clocksource or clockevent must be specified in DTS. Whatever
we're using alias or property.



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