drm: rcar-du: Update Gen3 output limitations

The R-Car Gen3 DU utilises the VSP1 hardware for memory access. The
limits on the RPF and WPF in this pipeline are 8190x8190.

Update the supported maximum sizes accordingly.
Signed-off-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

drivers/gpu/drm/rcar-du/rcar_du_kms.c

@@ -512,12 +512,22 @@ int rcar_du_modeset_init(struct rcar_du_device *rcdu)
 
 	dev->mode_config.min_width = 0;
 	dev->mode_config.min_height = 0;
-	dev->mode_config.max_width = 4095;
-	dev->mode_config.max_height = 2047;
 	dev->mode_config.normalize_zpos = true;
 	dev->mode_config.funcs = &rcar_du_mode_config_funcs;
 	dev->mode_config.helper_private = &rcar_du_mode_config_helper;
 
+	if (rcdu->info->gen < 3) {
+		dev->mode_config.max_width = 4095;
+		dev->mode_config.max_height = 2047;
+	} else {
+		/*
+		 * The Gen3 DU uses the VSP1 for memory access, and is limited
+		 * to frame sizes of 8190x8190.
+		 */
+		dev->mode_config.max_width = 8190;
+		dev->mode_config.max_height = 8190;
+	}
+
 	rcdu->num_crtcs = hweight8(rcdu->info->channels_mask);
 
 	ret = rcar_du_properties_init(rcdu);