amd/display: allow non-linear multi-planar formats

Accept non-linear buffers which use a multi-planar format, as long
as they don't use DCC.

Tested on GFX9 with NV12.
Signed-off-by: Simon Ser <contact@emersion.fr>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Harry Wentland <hwentlan@amd.com>
Cc: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Cc: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
Reviewed-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c

@@ -4071,13 +4071,6 @@ static bool dm_plane_format_mod_supported(struct drm_plane *plane,
 	if (modifier == DRM_FORMAT_MOD_LINEAR)
 		return true;
 
-	/*
-	 * The arbitrary tiling support for multiplane formats has not been hooked
-	 * up.
-	 */
-	if (info->num_planes > 1)
-		return false;
-
 	/*
 	 * For D swizzle the canonical modifier depends on the bpp, so check
 	 * it here.
@@ -4096,6 +4089,10 @@ static bool dm_plane_format_mod_supported(struct drm_plane *plane,
 		/* Per radeonsi comments 16/64 bpp are more complicated. */
 		if (info->cpp[0] != 4)
 			return false;
+		/* We support multi-planar formats, but not when combined with
+		 * additional DCC metadata planes. */
+		if (info->num_planes > 1)
+			return false;
 	}
 
 	return true;