Re: [Intel-gfx] [PATCHv3] drm/i915/fbc: Disable FBC when VT-d is enabled

["Ville Syrjälä" <ville.syrjala@linux.intel.com>]

On Wed, Nov 23, 2022 at 09:03:08AM +0530, Arun R Murthy wrote:
> The WaFbcTurnOffFbcWhenHyperVisorIsUsed is applicable for SKL, BXT and
> KBL.
> 
> Bspec: 0852
> 
> v2: Updated commit msg and corrected Bspec format(Jani N)
> v3: Updated the stepping information
> 
> Signed-off-by: Arun R Murthy <arun.r.murthy@intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_fbc.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_fbc.c b/drivers/gpu/drm/i915/display/intel_fbc.c
> index b5ee5ea0d010..7c06ad454a7d 100644
> --- a/drivers/gpu/drm/i915/display/intel_fbc.c
> +++ b/drivers/gpu/drm/i915/display/intel_fbc.c
> @@ -1652,9 +1652,10 @@ static int intel_sanitize_fbc_option(struct drm_i915_private *i915)
>  
>  static bool need_fbc_vtd_wa(struct drm_i915_private *i915)
>  {
> -	/* WaFbcTurnOffFbcWhenHyperVisorIsUsed:skl,bxt */
> +	/* WaFbcTurnOffFbcWhenHyperVisorIsUsed:skl,bxt,kbl */
>  	if (i915_vtd_active(i915) &&
> -	    (IS_SKYLAKE(i915) || IS_BROXTON(i915))) {
> +			(IS_SKYLAKE(i915) || IS_BROXTON(i915) ||
> +			IS_KBL_DISPLAY_STEP(i915, STEP_A0, STEP_B0))) {

No one careas about pre-production hw once the thing has shipped.

>  		drm_info(&i915->drm,
>  			 "Disabling framebuffer compression (FBC) to prevent screen flicker with VT-d enabled\n");
>  		return true;
> -- 
> 2.25.1

-- 
Ville Syrjälä
Intel