[PATCH] powerpc/powernv/idle: Round up latency and residency values

[Michael Ellerman]

Vaidyanathan Srinivasan <svaidy at linux.vnet.ibm.com> writes:

> On PowerNV platforms, firmware provides exit latency and
> target residency for each of the idle states in nano
> seconds.  Cpuidle framework expects the values in micro
> seconds.  Round up to nearest micro seconds to avoid errors
> in cases where the values are defined as fractional micro
> seconds.
>
> Default idle state of 'snooze' has exit latency of zero.  If
> other states have fractional micro second exit latency, they
> would get rounded down to zero micro second and make cpuidle
> framework choose deeper idle state when snooze loop is the
> right choice.
>
> Reported-by: Anton Blanchard <anton at samba.org>
> Signed-off-by: Vaidyanathan Srinivasan <svaidy at linux.vnet.ibm.com>

This sounds like a fairly bad bug, does it need a Fixes / Cc stable tag?

cheers