[PATCH v2 28/31] arm64: Generic timers support
Santosh Shilimkar
santosh.shilimkar at ti.com
Fri Aug 17 06:21:17 EDT 2012
On Tuesday 14 August 2012 11:22 PM, Catalin Marinas wrote:
> From: Marc Zyngier<marc.zyngier at arm.com>
>
> This patch adds support for the ARM generic timers with A64 instructions
> for accessing the timer registers. It uses the physical counter as the
> clock source and the virtual counter as sched_clock.
>
> The timer frequency can be specified via DT or read from the CNTFRQ_EL0
> register. The physical counter is also accessible from user space
> allowing fast gettimeofday() implementation.
>
> Signed-off-by: Marc Zyngier<marc.zyngier at arm.com>
> Signed-off-by: Will Deacon<will.deacon at arm.com>
> Signed-off-by: Catalin Marinas<catalin.marinas at arm.com>
> ---
[..]
> diff --git a/drivers/clocksource/arm_generic.c b/drivers/clocksource/arm_generic.c
> new file mode 100644
> index 0000000..05c898c
> --- /dev/null
> +++ b/drivers/clocksource/arm_generic.c
[..]
> +
> +static void __cpuinit arch_timer_setup(struct clock_event_device *clk)
> +{
> + /* Let's make sure the timer is off before doing anything else */
> + arch_timer_stop();
> +
> + clk->features = CLOCK_EVT_FEAT_ONESHOT;
Are these CPU timers wakeup capable or we need the wakeup capable
broadcast timer for low power wakeups ?
In that case C3STOP would be needed here.
Regards
santosh
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