[Intel-gfx] [PATCH] drm/i915/gt: Fix rc6 on Ivybridge

[Andi Shyti]

Hi Chris,

> The current rc6 threshold is larger than the evaluation interval on
> Ivybridge; it never enters rc6. Remove the special casing so it behaves
> like the other gen6/gen7, and we see rc6 residencies before we manually
> park the system.
> 
> Closes: https://gitlab.freedesktop.org/drm/intel/issues/1114
> Testcase: igt/i915_pm_rc6_residency/rc6-idle #ivb
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Andi Shyti <andi.shyti at intel.com>
> ---
>  drivers/gpu/drm/i915/gt/intel_rc6.c | 5 +----
>  1 file changed, 1 insertion(+), 4 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/gt/intel_rc6.c b/drivers/gpu/drm/i915/gt/intel_rc6.c
> index 01a99fdbb3c4..682f598f7042 100644
> --- a/drivers/gpu/drm/i915/gt/intel_rc6.c
> +++ b/drivers/gpu/drm/i915/gt/intel_rc6.c
> @@ -226,10 +226,7 @@ static void gen6_rc6_enable(struct intel_rc6 *rc6)
>  
>  	set(uncore, GEN6_RC_SLEEP, 0);
>  	set(uncore, GEN6_RC1e_THRESHOLD, 1000);
> -	if (IS_IVYBRIDGE(i915))
> -		set(uncore, GEN6_RC6_THRESHOLD, 125000);
> -	else
> -		set(uncore, GEN6_RC6_THRESHOLD, 50000);
> +	set(uncore, GEN6_RC6_THRESHOLD, 50000);

why was is set like this in a first place?

Thanks,
Andi