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Date: Mon, 28 Nov 2011 22:47:52 +1100
From: Anton Blanchard <anton@samba.org>
To: Kumar Gala <galak@kernel.crashing.org>
Subject: Re: [PATCH 2/6] powerpc/time: Use clockevents_calc_mult_shift
Message-ID: <20111128224752.6694154b@kryten>
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Hi Kumar,

> > static void register_decrementer_clockevent(int cpu)
> > {
> > 	struct clock_event_device *dec = &per_cpu(decrementers,
> > cpu).event; @@ -955,7 +928,8 @@ static void __init
> > init_decrementer_cloc {
> > 	int cpu = smp_processor_id();
> > 
> > -	setup_clockevent_multiplier(ppc_tb_freq);
> > +	clockevents_calc_mult_shift(&decrementer_clockevent,
> > ppc_tb_freq, 4); +
> 
> Where's this magic 4 come from?

No better reason than that's what most other users do. We weren't
placing any limits on the shift/multiply in the old loop I don't think
we need to, so we could probably just use 1 instead.

Anton