drm: Handle connector tile support only for modes that match tile size

DRM Fb driver expects multiple CRTCs if it sees connector->has_tile
is set, but we need to handle tile support and look for multiple CRTCs
only for the modes that match the tile size. The other modes should
be able to be displayed without tile support or uisng single CRTC.

This patch adds the check to match the tile size with requested mode
to handle the tile support.

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Dave Airlie <airlied@redhat.com>
Signed-off-by: Manasi Navare <manasi.d.navare@intel.com>
Reviewed-by: Dave Airlie <airlied@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191211212433.18185-1-manasi.d.navare@intel.com

drivers/gpu/drm/drm_fb_helper.c

@@ -1576,7 +1576,9 @@ static int drm_fb_helper_single_fb_probe(struct drm_fb_helper *fb_helper,
 		for (j = 0; j < mode_set->num_connectors; j++) {
 			struct drm_connector *connector = mode_set->connectors[j];
 
-			if (connector->has_tile) {
+			if (connector->has_tile &&
+			    desired_mode->hdisplay == connector->tile_h_size &&
+			    desired_mode->vdisplay == connector->tile_v_size) {
 				lasth = (connector->tile_h_loc == (connector->num_h_tile - 1));
 				lastv = (connector->tile_v_loc == (connector->num_v_tile - 1));
 				/* cloning to multiple tiles is just crazy-talk, so: */