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

On 14/05/13 10:23, Linus Walleij wrote:

On Tue, May 14, 2013 at 10:46 AM, Srinivas KANDAGATLA
[off-list ref] wrote:

quoted

On 13/05/13 20:05, Linus Walleij wrote:

quoted

quoted

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?

I think it makes sense to shutdown the timer on other cores on request.
I will fix this.

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.

Thankyou for the advice,
I will definitely try to implement this.

Thanks,
srini

Yours,
Linus Walleij