Re: [PATCH v9 4/9] clocksource/drivers/arm_arch_timer: use readq to get 64-bit CNTVCT

[Timur Tabi]

Will Deacon wrote:
> > >  {
> > >-	u32 vct_lo, vct_hi, tmp_hi;
> > >-
> > >-	do {
> > >-		vct_hi = readl_relaxed(arch_counter_base + CNTVCT_HI);
> > >-		vct_lo = readl_relaxed(arch_counter_base + CNTVCT_LO);
> > >-		tmp_hi = readl_relaxed(arch_counter_base + CNTVCT_HI);
> > >-	} while (vct_hi != tmp_hi);
> > >-
> > >-	return ((u64) vct_hi << 32) | vct_lo;
> > >+	return readq(arch_counter_base + CNTVCT_LO);
> Please drop this patch. It doesn't work.

On systems where readq() does work, wouldn't it be more optimal than the 
above while-loop?

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