[Intel-gfx] [PATCH] drm/i915/vlv: fix RC6 residency time calculation

[Imre Deak]

On ma, 2015-05-18 at 18:46 +0300, Imre Deak wrote:
> The divider value to convert from CZ clock rate to ms needs a +1
> adjustment on VLV just like on CHV. This matches both the spec and
> the accuracy test by pm_rc6_residency.
> 
> Testcase: igt/pm_rc6_residency
> Signed-off-by: Imre Deak <imre.deak at intel.com>

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=76877

Rodrigo, could you review this?

Thanks,
Imre

> ---
>  drivers/gpu/drm/i915/i915_sysfs.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/i915_sysfs.c b/drivers/gpu/drm/i915/i915_sysfs.c
> index 2476268..aa99efc 100644
> --- a/drivers/gpu/drm/i915/i915_sysfs.c
> +++ b/drivers/gpu/drm/i915/i915_sysfs.c
> @@ -76,6 +76,8 @@ static u32 calc_residency(struct drm_device *dev, const u32 reg)
>  				/* chv counts are one less */
>  				czcount_30ns += 1;
>  			}
> +		} else {
> +			czcount_30ns += 1;
>  		}
>  
>  		if (units == 0)