[PATCH V4 6/9] cpuidle/ppc: Add basic infrastructure to enable the broadcast framework on ppc

[Thomas Gleixner]

On Fri, 29 Nov 2013, Preeti U Murthy wrote:
> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
> index b44b52c..cafa788 100644
> --- a/arch/powerpc/Kconfig
> +++ b/arch/powerpc/Kconfig
> @@ -129,6 +129,8 @@ config PPC
>  	select GENERIC_CMOS_UPDATE
>  	select GENERIC_TIME_VSYSCALL_OLD
>  	select GENERIC_CLOCKEVENTS
> +	select GENERIC_CLOCKEVENTS_BROADCAST
> +	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST

What's the point of this config switch? It's nowhere used.

> +static int broadcast_set_next_event(unsigned long evt,
> +					struct clock_event_device *dev)
> +{
> +	return 0;
> +}
> +
> +static void broadcast_set_mode(enum clock_event_mode mode,
> +				 struct clock_event_device *dev)
> +{
> +	if (mode != CLOCK_EVT_MODE_ONESHOT)
> +		broadcast_set_next_event(DECREMENTER_MAX, dev);

What's the point of calling an empty function?  

> +}
> +
>  static void decrementer_set_mode(enum clock_event_mode mode,
>  				 struct clock_event_device *dev)
>  {
> @@ -840,6 +869,19 @@ static void register_decrementer_clockevent(int cpu)
>  	clockevents_register_device(dec);
>  }
>  
> +static void register_broadcast_clockevent(int cpu)
> +{
> +	struct clock_event_device *bc_evt = &bc_timer;
> +
> +	*bc_evt = broadcast_clockevent;
> +	bc_evt->cpumask = cpu_possible_mask;
> +
> +	printk_once(KERN_DEBUG "clockevent: %s mult[%x] shift[%d] cpu[%d]\n",
> +		    bc_evt->name, bc_evt->mult, bc_evt->shift, cpu);
> +
> +	clockevents_register_device(bc_evt);
> +}
> +
>  static void __init init_decrementer_clockevent(void)
>  {
>  	int cpu = smp_processor_id();
> @@ -854,6 +896,19 @@ static void __init init_decrementer_clockevent(void)
>  	register_decrementer_clockevent(cpu);
>  }
>  
> +static void __init init_broadcast_clockevent(void)
> +{
> +	int cpu = smp_processor_id();
> +
> +	clockevents_calc_mult_shift(&broadcast_clockevent, ppc_tb_freq, 4);
> +
> +	broadcast_clockevent.max_delta_ns =
> +		clockevent_delta2ns(DECREMENTER_MAX, &broadcast_clockevent);
> +	broadcast_clockevent.min_delta_ns =
> +		clockevent_delta2ns(2, &broadcast_clockevent);

clockevents_config()

Thanks,

	tglx