[Intel-xe] [PATCH] drm/xe/display: Append dma_buf fences to framebuffer fences

[Shankar, Uma]

> -----Original Message-----
> From: Intel-xe <intel-xe-bounces at lists.freedesktop.org> On Behalf Of José Roberto
> de Souza
> Sent: Wednesday, June 7, 2023 1:50 AM
> To: intel-xe at lists.freedesktop.org
> Subject: [Intel-xe] [PATCH] drm/xe/display: Append dma_buf fences to framebuffer
> fences
> 
> This is required to comply with KMS page flip requirements, and it is the only way to
> synchronize framebuffer scanouts in Xe KMD.
> 
> UMDs are expected to attach a syncobj that will be signaled at the end of the GPU
> job that is rendering in the framebuffer.
> This way, the compositor can send jobs to the GPU to render the framebuffer and
> without having to wait for it to complete, queue the page flip in KMS.
> 
> This fixes display glitches.

Looks Good to me.
Reviewed-by: Uma Shankar <uma.shankar at intel.com>

@Ville: Can you also check this once and confirm.

Regards,
Uma Shankar

> Link: https://gitlab.freedesktop.org/mesa/mesa/-/issues/8923
> Signed-off-by: José Roberto de Souza <jose.souza at intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_atomic_plane.c | 13 ++++++++++++-
>  1 file changed, 12 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_atomic_plane.c
> b/drivers/gpu/drm/i915/display/intel_atomic_plane.c
> index b756561f08bd1..a3f30a319e4c0 100644
> --- a/drivers/gpu/drm/i915/display/intel_atomic_plane.c
> +++ b/drivers/gpu/drm/i915/display/intel_atomic_plane.c
> @@ -32,6 +32,7 @@
>   */
> 
>  #include <drm/drm_atomic_helper.h>
> +#include <drm/drm_gem_atomic_helper.h>
>  #include <drm/drm_blend.h>
>  #include <drm/drm_fourcc.h>
> 
> @@ -1120,10 +1121,20 @@ intel_prepare_plane_fb(struct drm_plane *_plane,
> 
>  	return ret;
>  #else
> +	int ret;
> +
>  	if (!intel_fb_obj(new_plane_state->hw.fb))
>  		return 0;
> 
> -	return intel_plane_pin_fb(new_plane_state);
> +	ret = intel_plane_pin_fb(new_plane_state);
> +	if (ret)
> +		return ret;
> +
> +	ret = drm_gem_plane_helper_prepare_fb(_plane, _new_plane_state);
> +	if (ret)
> +		intel_plane_unpin_fb(new_plane_state);
> +
> +	return ret;
>  #endif
>  }
> 
> --
> 2.41.0