drm/i915/dp: add helper for checking for UHBR link rate

Helpful abstraction to avoid duplication.
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/fe9a222ad900da797c989de9f7fa13928d2c9861.1631191763.git.jani.nikula@intel.com

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

@@ -115,6 +115,12 @@ bool intel_dp_is_edp(struct intel_dp *intel_dp)
 static void intel_dp_unset_edid(struct intel_dp *intel_dp);
 static int intel_dp_dsc_compute_bpp(struct intel_dp *intel_dp, u8 dsc_max_bpc);
 
+/* Is link rate UHBR and thus 128b/132b? */
+bool intel_dp_is_uhbr(const struct intel_crtc_state *crtc_state)
+{
+	return crtc_state->port_clock >= 1000000;
+}
+
 /* update sink rates from dpcd */
 static void intel_dp_set_sink_rates(struct intel_dp *intel_dp)
 {

drivers/gpu/drm/i915/display/intel_dp.h

@@ -58,6 +58,7 @@ int intel_dp_compute_config(struct intel_encoder *encoder,
 			    struct intel_crtc_state *pipe_config,
 			    struct drm_connector_state *conn_state);
 bool intel_dp_is_edp(struct intel_dp *intel_dp);
+bool intel_dp_is_uhbr(const struct intel_crtc_state *crtc_state);
 bool intel_dp_is_port_edp(struct drm_i915_private *dev_priv, enum port port);
 enum irqreturn intel_dp_hpd_pulse(struct intel_digital_port *dig_port,
 				  bool long_hpd);