[RFC 2/8] ARM:global_timer: Add ARM global timer support.

[Linus Walleij]

On Tue, May 14, 2013 at 10:46 AM, Srinivas KANDAGATLA
<srinivas.kandagatla at st.com> wrote:
> On 13/05/13 20:05, Linus Walleij wrote:

>> Why are you enabling the timer in unused and shutdown mode?
>>
>> This doesn't make sense.
>
> It is because we are using the global-timer block for both clocksource
> and clockevents and we do not want the clocksource to disappear when
> clockevent is unused/shutdown.

As this is clearly a per-cpu timer (correct? atleast the driver is
written that way) and say you have 4 CPUs, why would you not shut down
the timer on cores 1,2,3 and only leave the timer on core 0 on?

The kernel will by necessity not shut down the clock event on core
0 anyway.

On a related note: don't you want to use the counter in this block as
sched_clock() as well? (I guess so, as you do not seem to have
anything else on this system.) It'd probably need to be a separate
Kconfig option and can surely be done later but keep it in mind.

Yours,
Linus Walleij