[PATCH v3 02/10] clocksource:arm_global_timer: Add ARM global timer support.
Arnd Bergmann
arnd at arndb.de
Fri Jun 21 05:02:30 EST 2013
On Thursday 20 June 2013, Srinivas KANDAGATLA wrote:
> +static u64 gt_counter_read(void)
> +{
> + u64 counter;
> + u32 lower;
> + u32 upper, old_upper;
> +
> + upper = __raw_readl(gt_base + GT_COUNTER1);
> + do {
> + old_upper = upper;
> + lower = __raw_readl(gt_base + GT_COUNTER0);
> + upper = __raw_readl(gt_base + GT_COUNTER1);
> + } while (upper != old_upper);
> +
> + counter = upper;
> + counter <<= 32;
> + counter |= lower;
> + return counter;
> +}
Please replace __raw_readl etc with the non-__raw variants
throughout the code.
The __raw accessors are not endian safe and are not meant
for device drivers. If you are worried about latency from
extra barriers, use readl_relaxed().
Arnd
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