[PATCH v3 1/2] drm/i915: Disable DSB in Xe KMD

[Francois Dugast]

On Thu, Jan 04, 2024 at 08:05:56AM -0800, José Roberto de Souza wrote:
> Often getting DBS overflows when starting Xorg or Wayland compositors
> when running Xe KMD.

s/DBS overflows/DSB overflows/

> Issue was reported but nothing was done, so disabling DSB as whole
> until properly fixed in Xe KMD.
> 
> v2:
> - move check to HAS_DSB(Jani)
> 
> v3:
> - use IS_ENABLED(I915) check in intel_dsb_prepare()
> 
> Link: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/989
> Link: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/1031
> Link: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/1072
> Cc: Animesh Manna <animesh.manna at intel.com>
> Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
> Cc: Jani Nikula <jani.nikula at intel.com>
> Signed-off-by: José Roberto de Souza <jose.souza at intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_dsb.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_dsb.c b/drivers/gpu/drm/i915/display/intel_dsb.c
> index 482c28b5c2de5..a6c7122fd671d 100644
> --- a/drivers/gpu/drm/i915/display/intel_dsb.c
> +++ b/drivers/gpu/drm/i915/display/intel_dsb.c
> @@ -453,6 +453,10 @@ struct intel_dsb *intel_dsb_prepare(const struct intel_crtc_state *crtc_state,
>  	if (!HAS_DSB(i915))
>  		return NULL;
>  
> +	/* TODO: DSB is broken in Xe KMD, so disabling it until fixed */
> +	if (!IS_ENABLED(I915))
> +		return NULL;
> +
>  	dsb = kzalloc(sizeof(*dsb), GFP_KERNEL);
>  	if (!dsb)
>  		goto out;
> -- 
> 2.43.0
>