Re: [PATCH] drm/i915/display: Disable AuxCCS framebuffers if built for Xe

[Jani Nikula <jani.nikula@linux.intel.com>]

On Mon, 26 Feb 2024, Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com> wrote:
> AuxCCS framebuffers don't work on Xe driver hence disable them
> from plane capabilities until they are fixed. FlatCCS framebuffers
> work and they are left enabled. CCS is left untouched for i915
> driver.
>
> Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/933
> Signed-off-by: Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com>
> ---
> Let's try adding those ifdefs as IS_ENABLED(I915) will result in
> warnings from checkpatch and there was wishes not to break
> universal plane into smaller parts. IS_ENABLED(CONFIG_I915) is
> always true when building both Xe and i915.

Please ignore the checkpatch warning in this case.

BR,
Jani.

>
>  .../gpu/drm/i915/display/skl_universal_plane.c  | 17 +++++++++++++++++
>  1 file changed, 17 insertions(+)
>
> diff --git a/drivers/gpu/drm/i915/display/skl_universal_plane.c b/drivers/gpu/drm/i915/display/skl_universal_plane.c
> index e941e2e4fd14..7e0a7283d01d 100644
> --- a/drivers/gpu/drm/i915/display/skl_universal_plane.c
> +++ b/drivers/gpu/drm/i915/display/skl_universal_plane.c
> @@ -2283,6 +2283,15 @@ static bool gen12_plane_has_mc_ccs(struct drm_i915_private *i915,
>  	return plane_id < PLANE_SPRITE4;
>  }
>  
> +static bool running_on_i915(void)
> +{
> +#ifdef I915
> +	return true;
> +#else
> +	return false;
> +#endif
> +}
> +
>  static u8 skl_get_plane_caps(struct drm_i915_private *i915,
>  			     enum pipe pipe, enum plane_id plane_id)
>  {
> @@ -2295,6 +2304,14 @@ static u8 skl_get_plane_caps(struct drm_i915_private *i915,
>  	if (HAS_4TILE(i915))
>  		caps |= INTEL_PLANE_CAP_TILING_4;
>  
> +	/*
> +	 * FIXME: Below if(running_on_i915()..) is because Xe driver
> +	 * can't use AuxCCS framebuffers. Once they are fixed this need to be
> +	 * removed.
> +	 */
> +	if (!running_on_i915() && !HAS_FLAT_CCS(i915))
> +		return caps;
> +
>  	if (skl_plane_has_rc_ccs(i915, pipe, plane_id)) {
>  		caps |= INTEL_PLANE_CAP_CCS_RC;
>  		if (DISPLAY_VER(i915) >= 12)

-- 
Jani Nikula, Intel