drm/i915: Factor out common parts from TypeC port handling functions

Factor out helpers reading/parsing the TypeC specific registers, making
current users of them clearer and letting us use them later.

While at it also:
- Simplify icl_tc_phy_connect() with an early return in legacy mode.
- Simplify the live status check using one bitmask for all HPD bits.
- Remove a micro-optimisation of the repeated safe-mode clearing.
- Make sure we fix the legacy port flag in all cases.

Except for the last two, no functional changes.

v2:
- Don't do reg reads at variable declarations. (Jani)
- Prevent constant truncated compiler warning when assigning the
  valid_hpd_mask. (Nick)
- s/intel_tc_port_get_lane_info/intel_tc_port_get_lane_mask/ (Ville)
v3:
- Make valid_hpd_mask init clear. (Ville)

Cc: José Roberto de Souza <jose.souza@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190628143635.22066-10-imre.deak@intel.com

1 files changed, 4 insertions, 7 deletions

diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c b/drivers/gpu/drm/i915/display/intel_ddi.c
index c9143e2a6994..2be7cdc319ba 100644
--- a/drivers/gpu/drm/i915/display/intel_ddi.c
+++ b/drivers/gpu/drm/i915/display/intel_ddi.c
@@ -2996,8 +2996,7 @@ static void icl_program_mg_dp_mode(struct intel_digital_port *intel_dig_port)
 {
 	struct drm_i915_private *dev_priv = to_i915(intel_dig_port->base.base.dev);
 	enum port port = intel_dig_port->base.port;
-	enum tc_port tc_port = intel_port_to_tc(dev_priv, port);
-	u32 ln0, ln1, lane_info;
+	u32 ln0, ln1, lane_mask;
 
 	if (intel_dig_port->tc_mode == TC_PORT_TBT_ALT)
 		return;
@@ -3010,11 +3009,9 @@ static void icl_program_mg_dp_mode(struct intel_digital_port *intel_dig_port)
 		ln0 &= ~(MG_DP_MODE_CFG_DP_X1_MODE | MG_DP_MODE_CFG_DP_X2_MODE);
 		ln1 &= ~(MG_DP_MODE_CFG_DP_X1_MODE | MG_DP_MODE_CFG_DP_X2_MODE);
 
-		lane_info = (I915_READ(PORT_TX_DFLEXDPSP) &
-			     DP_LANE_ASSIGNMENT_MASK(tc_port)) >>
-			    DP_LANE_ASSIGNMENT_SHIFT(tc_port);
+		lane_mask = intel_tc_port_get_lane_mask(intel_dig_port);
 
-		switch (lane_info) {
+		switch (lane_mask) {
 		case 0x1:
 		case 0x4:
 			break;
@@ -3039,7 +3036,7 @@ static void icl_program_mg_dp_mode(struct intel_digital_port *intel_dig_port)
 			       MG_DP_MODE_CFG_DP_X2_MODE;
 			break;
 		default:
-			MISSING_CASE(lane_info);
+			MISSING_CASE(lane_mask);
 		}
 		break;