drm/i915/tgl/dsi: Do not override TA_SURE

Do not override TA_SURE timing parameter to
zero for DSI 8X frequency 800MHz or below on
TGL.
Signed-off-by: Vandita Kulkarni <vandita.kulkarni@intel.com>
Reviewed-by: Uma Shankar <uma.shankar@intel.com>
Signed-off-by: Uma Shankar <uma.shankar@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190730073648.5157-4-vandita.kulkarni@intel.com

drivers/gpu/drm/i915/display/icl_dsi.c

@@ -530,18 +530,20 @@ static void gen11_dsi_setup_dphy_timings(struct intel_encoder *encoder)
 	 * a value '0' inside TA_PARAM_REGISTERS otherwise
 	 * leave all fields at HW default values.
 	 */
-	if (intel_dsi_bitrate(intel_dsi) <= 800000) {
-		for_each_dsi_port(port, intel_dsi->ports) {
-			tmp = I915_READ(DPHY_TA_TIMING_PARAM(port));
-			tmp &= ~TA_SURE_MASK;
-			tmp |= TA_SURE_OVERRIDE | TA_SURE(0);
-			I915_WRITE(DPHY_TA_TIMING_PARAM(port), tmp);
-
-			/* shadow register inside display core */
-			tmp = I915_READ(DSI_TA_TIMING_PARAM(port));
-			tmp &= ~TA_SURE_MASK;
-			tmp |= TA_SURE_OVERRIDE | TA_SURE(0);
-			I915_WRITE(DSI_TA_TIMING_PARAM(port), tmp);
+	if (IS_GEN(dev_priv, 11)) {
+		if (intel_dsi_bitrate(intel_dsi) <= 800000) {
+			for_each_dsi_port(port, intel_dsi->ports) {
+				tmp = I915_READ(DPHY_TA_TIMING_PARAM(port));
+				tmp &= ~TA_SURE_MASK;
+				tmp |= TA_SURE_OVERRIDE | TA_SURE(0);
+				I915_WRITE(DPHY_TA_TIMING_PARAM(port), tmp);
+
+				/* shadow register inside display core */
+				tmp = I915_READ(DSI_TA_TIMING_PARAM(port));
+				tmp &= ~TA_SURE_MASK;
+				tmp |= TA_SURE_OVERRIDE | TA_SURE(0);
+				I915_WRITE(DSI_TA_TIMING_PARAM(port), tmp);
+			}
 		}
 	}