Re: [PATCH v2 1/3] drm/i915/fbc: update the supported FP16 formats

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

On Mon, Oct 26, 2026 at 04:55:06PM +0200, Vinod Govindapillai wrote:
> FBC is supported with FP16 formats with or without alpha. At the
> same time modify the function name for the FP16 format check and
> simplify the FP16 format check calls.
> 
> Bspec: 68904
> Signed-off-by: Vinod Govindapillai <vinod.govindapillai@intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_fbc.c | 21 +++++++--------------
>  1 file changed, 7 insertions(+), 14 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_fbc.c b/drivers/gpu/drm/i915/display/intel_fbc.c
> index 5694d20773f8..dbb16a9ec69d 100644
> --- a/drivers/gpu/drm/i915/display/intel_fbc.c
> +++ b/drivers/gpu/drm/i915/display/intel_fbc.c
> @@ -1180,14 +1180,15 @@ static bool lnl_fbc_pixel_format_is_valid(const struct intel_plane_state *plane_
>  	}
>  }
>  
> -static bool
> -xe3p_lpd_fbc_fp16_format_is_valid(const struct intel_plane_state *plane_state)
> +static bool intel_fbc_is_fp16_format(const struct intel_plane_state *plane_state)
>  {
>  	const struct drm_framebuffer *fb = plane_state->hw.fb;
>  
>  	switch (fb->format->format) {
>  	case DRM_FORMAT_ARGB16161616F:
> +	case DRM_FORMAT_XRGB16161616F:
>  	case DRM_FORMAT_ABGR16161616F:
> +	case DRM_FORMAT_XBGR16161616F:
>  		return true;
>  	default:
>  		return false;
> @@ -1196,24 +1197,16 @@ xe3p_lpd_fbc_fp16_format_is_valid(const struct intel_plane_state *plane_state)
>  
>  static bool xe3p_lpd_fbc_pixel_format_is_valid(const struct intel_plane_state *plane_state)
>  {
> -	if (lnl_fbc_pixel_format_is_valid(plane_state))
> -		return true;
> -
> -	if (xe3p_lpd_fbc_fp16_format_is_valid(plane_state))
> -		return true;
> -
> -	return false;
> +	return lnl_fbc_pixel_format_is_valid(plane_state) ||
> +	       intel_fbc_is_fp16_format(plane_state);

This is getting super messy. Would be much simpler to just list
the actual supported pixel formats here instead of trying to
this hard to follow inheritance thing.

>  }
>  
>  bool intel_fbc_need_pixel_normalizer(const struct intel_plane_state *plane_state)
>  {
>  	struct intel_display *display = to_intel_display(plane_state);
>  
> -	if (HAS_PIXEL_NORMALIZER(display) &&
> -	    xe3p_lpd_fbc_fp16_format_is_valid(plane_state))
> -		return true;
> -
> -	return false;
> +	return HAS_PIXEL_NORMALIZER(display) &&
> +	       intel_fbc_is_fp16_format(plane_state);
>  }
>  
>  static bool pixel_format_is_valid(const struct intel_plane_state *plane_state)
> -- 
> 2.43.0

-- 
Ville Syrjälä
Intel