[PATCH] ARM: clps711x: convert to clocksource/clockevents

[Linus Walleij]

On Thu, Aug 30, 2012 at 10:02 AM, Alexander Shiyan <shc_work at mail.ru> wrote:
> On Thu, 30 Aug 2012 18:37:58 +0200
> Linus Walleij <linus.walleij at linaro.org> wrote:
>
>> This converts the ageing clps711x timer driver to the modern
>> clocksource/clockevent API.
>
> The patch does not account for the changes that I sent to the mailing list
> recently, where I did support different clock frequencies for the processor.

No problem, I can rebase on top of your patches as soon as you
submit them to ARM SoC so I can see them in linux-next.

>> This was blind-coded using the datasheet, it'd be great if someone
>> who has this machine could test it.
> ...
>> +     /* Set both timers to 512 kHz */
>
> The patch uses a second timer, which does not allow its use for other purposes,

What does this mean? Reading the datasheet it didn't say anything about
this timer being dedicated to something else.

I am using TC1D as clocksource and TC2D as clockevent, repurposing
it from the previous use as singe time source.

Doing "git grep TC1D" I cannot see any code in the kernel making use
of this timer?

I could think of things like the boot loader or firmware setting it up
to run in free-running mode ... in that case we use
it as clocksource without initialization as long as we know what
frequency it's running on.

As far as I could understand from the datasheet there is really
no way to actually disable these timers, so they always run
anyway?

> I have also tried to do something like this without using additional processor
> resources, but not yet brought to the finish line yet.

OK do you think you can switch the clps71x over to generic time and
clockevents inspired by this patch or so?

Yours,
Linus Walleij