[Intel-gfx] [PATCH 2/2] drm/i915/fbc: Allow on unfenced surfaces, for recent gen

[Zanoni, Paulo R]

Em Qui, 2016-08-18 às 09:21 +0100, Chris Wilson escreveu:
> Only fbc1 is tied to using a fence. Later iterations of fbc are more
> flexible and allow operation on unfenced frontbuffers.

But then we'll lose GTT tracking - which we currently rely on - and I'm
87.5% sure we'll need to implement some workarounds we skipped.

> 
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Daniel Vetter <daniel.vetter at intel.com>
> Cc: "Zanoni, Paulo R" <paulo.r.zanoni at intel.com>
> ---
>  drivers/gpu/drm/i915/intel_fbc.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_fbc.c
> b/drivers/gpu/drm/i915/intel_fbc.c
> index 57e1ca624d73..9534f90c6551 100644
> --- a/drivers/gpu/drm/i915/intel_fbc.c
> +++ b/drivers/gpu/drm/i915/intel_fbc.c
> @@ -789,8 +789,10 @@ static bool intel_fbc_can_activate(struct
> intel_crtc *crtc)
>  	 */
>  	if (cache->fb.tiling_mode != I915_TILING_X ||
>  	    cache->fb.fence_reg == I915_FENCE_REG_NONE) {
> -		fbc->no_fbc_reason = "framebuffer not tiled or
> fenced";
> -		return false;
> +		if (INTEL_GEN(dev_priv) < 5) {
> +			fbc->no_fbc_reason = "framebuffer not tiled
> or fenced";
> +			return false;
> +		}
>  	}
>  	if (INTEL_INFO(dev_priv)->gen <= 4 && !IS_G4X(dev_priv) &&
>  	    cache->plane.rotation != DRM_ROTATE_0) {