Subject: [PATCH 1/2] ARM: OMAP2+: Initialize timers later with late_time_init

From: [email-masked] (Grygorii Strashko)
Date: Tue, 1 Dec 2015 15:52:09 +0200

On 11/30/2015 06:26 PM, Tony Lindgren wrote:
> We don't need timers right away and initializing them later gives us few
> nice things like interrupts and kmalloc. As the timers have a dependency
> to the clock framework, we're better off initializing things later rather
> than early if things go wrong. And this allows us to make the mux clock
> driver needed for system timers into early_platform drivers.
> 
> Note that smp_prepare_cpus() will get called later on during the init so
> we just need to local_irq_enable/disable for clocksource_probe().
> 
> Cc: Felipe Balbi <[email-masked]>
> Cc: Grygorii Strashko <[email-masked]>
> Cc: Paul Walmsley <[email-masked]>
> Cc: Tero Kristo <[email-masked]>
> Signed-off-by: Tony Lindgren <[email-masked]>
> ---
>   arch/arm/mach-omap2/timer.c | 46 +++++++++++++++++++++++++++++++++++++++------
>   1 file changed, 40 insertions(+), 6 deletions(-)
> 
> diff --git a/arch/arm/mach-omap2/timer.c b/arch/arm/mach-omap2/timer.c
> index b18ebbe..68bf482 100644
> --- a/arch/arm/mach-omap2/timer.c
> +++ b/arch/arm/mach-omap2/timer.c
> @@ -478,36 +478,56 @@ static void __init __omap_sync32k_timer_init(int clkev_nr, const char *clkev_src
>   	omap2_gp_clockevent_init(clkev_nr, clkev_src, clkev_prop);
>   
>   	/* Enable the use of clocksource="gp_timer" kernel parameter */
> +	local_irq_disable();
>   	if (use_gptimer_clksrc || gptimer)
>   		omap2_gptimer_clocksource_init(clksrc_nr, clksrc_src,
>   						clksrc_prop);
>   	else
>   		omap2_sync32k_clocksource_init();
> +	local_irq_enable();

So, this will be called now after sched_clock_postinit() and to W/A warnings
you've added local_irq_disable()/local_irq_enable(). Am I right?

Are you sure this is safe?

-- 
regards,
-grygorii