[Intel-gfx] [PATCH] drm/i915/mtl: Reset only one lane in case of MFD

[Mika Kahola]

In case when only two or less lanes are owned such as MFD (DP-alt with x2 lanes)
we need to reset only one lane (lane0). With only x2 lanes we don't need
to poll for the phy current status on both lanes since only the owned lane
will respond.

Signed-off-by: Mika Kahola <mika.kahola at intel.com>
---
 drivers/gpu/drm/i915/display/intel_cx0_phy.c | 39 ++++++++++++--------
 1 file changed, 23 insertions(+), 16 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_cx0_phy.c b/drivers/gpu/drm/i915/display/intel_cx0_phy.c
index ee6902118860..b8c812c5b33f 100644
--- a/drivers/gpu/drm/i915/display/intel_cx0_phy.c
+++ b/drivers/gpu/drm/i915/display/intel_cx0_phy.c
@@ -2528,13 +2528,23 @@ static u32 intel_cx0_get_pclk_refclk_ack(u8 lane_mask)
 	return val;
 }
 
-/* FIXME: Some Type-C cases need not reset both the lanes. Handle those cases. */
-static void intel_cx0_phy_lane_reset(struct drm_i915_private *i915, enum port port,
+static void intel_cx0_phy_lane_reset(struct drm_i915_private *i915,
+				     struct intel_encoder *encoder,
 				     bool lane_reversal)
 {
+	enum port port = encoder->port;
 	enum phy phy = intel_port_to_phy(i915, port);
+	u8 fia_max =  intel_tc_port_fia_max_lane_count(enc_to_dig_port(encoder));
 	u8 lane_mask = lane_reversal ? INTEL_CX0_LANE1 :
 				  INTEL_CX0_LANE0;
+	u32 lane_pipe_reset = fia_max > 2 ?
+			      XELPDP_LANE_PIPE_RESET(0) |
+			      XELPDP_LANE_PIPE_RESET(1) :
+			      XELPDP_LANE_PIPE_RESET(0);
+	u32 lane_phy_current_status = fia_max > 2 ?
+				      XELPDP_LANE_PHY_CURRENT_STATUS(0) |
+				      XELPDP_LANE_PHY_CURRENT_STATUS(1) :
+				      XELPDP_LANE_PHY_CURRENT_STATUS(0);
 
 	if (__intel_de_wait_for_register(i915, XELPDP_PORT_BUF_CTL1(port),
 					 XELPDP_PORT_BUF_SOC_PHY_READY,
@@ -2545,23 +2555,24 @@ static void intel_cx0_phy_lane_reset(struct drm_i915_private *i915, enum port po
 
 	intel_de_rmw(i915, XELPDP_PORT_BUF_CTL2(port),
 		     XELPDP_LANE_PIPE_RESET(0) | XELPDP_LANE_PIPE_RESET(1),
-		     XELPDP_LANE_PIPE_RESET(0) | XELPDP_LANE_PIPE_RESET(1));
+		     lane_pipe_reset);
 
 	if (__intel_de_wait_for_register(i915, XELPDP_PORT_BUF_CTL2(port),
-					 XELPDP_LANE_PHY_CURRENT_STATUS(0) |
-					 XELPDP_LANE_PHY_CURRENT_STATUS(1),
-					 XELPDP_LANE_PHY_CURRENT_STATUS(0) |
-					 XELPDP_LANE_PHY_CURRENT_STATUS(1),
+					 lane_phy_current_status, lane_phy_current_status,
 					 XELPDP_PORT_RESET_START_TIMEOUT_US, 0, NULL))
 		drm_warn(&i915->drm, "PHY %c failed to bring out of Lane reset after %dus.\n",
 			 phy_name(phy), XELPDP_PORT_RESET_START_TIMEOUT_US);
 
 	intel_de_rmw(i915, XELPDP_PORT_CLOCK_CTL(port),
-		     intel_cx0_get_pclk_refclk_request(INTEL_CX0_BOTH_LANES),
+		     intel_cx0_get_pclk_refclk_request(fia_max > 2 ?
+						       INTEL_CX0_BOTH_LANES :
+						       INTEL_CX0_LANE0),
 		     intel_cx0_get_pclk_refclk_request(lane_mask));
 
 	if (__intel_de_wait_for_register(i915, XELPDP_PORT_CLOCK_CTL(port),
-					 intel_cx0_get_pclk_refclk_ack(INTEL_CX0_BOTH_LANES),
+					 intel_cx0_get_pclk_refclk_ack(fia_max > 2 ?
+								       INTEL_CX0_BOTH_LANES :
+								       INTEL_CX0_LANE0),
 					 intel_cx0_get_pclk_refclk_ack(lane_mask),
 					 XELPDP_REFCLK_ENABLE_TIMEOUT_US, 0, NULL))
 		drm_warn(&i915->drm, "PHY %c failed to request refclk after %dus.\n",
@@ -2571,13 +2582,9 @@ static void intel_cx0_phy_lane_reset(struct drm_i915_private *i915, enum port po
 					    CX0_P2_STATE_RESET);
 	intel_cx0_setup_powerdown(i915, port);
 
-	intel_de_rmw(i915, XELPDP_PORT_BUF_CTL2(port),
-		     XELPDP_LANE_PIPE_RESET(0) | XELPDP_LANE_PIPE_RESET(1),
-		     0);
+	intel_de_rmw(i915, XELPDP_PORT_BUF_CTL2(port), lane_pipe_reset, 0);
 
-	if (intel_de_wait_for_clear(i915, XELPDP_PORT_BUF_CTL2(port),
-				    XELPDP_LANE_PHY_CURRENT_STATUS(0) |
-				    XELPDP_LANE_PHY_CURRENT_STATUS(1),
+	if (intel_de_wait_for_clear(i915, XELPDP_PORT_BUF_CTL2(port), lane_phy_current_status,
 				    XELPDP_PORT_RESET_END_TIMEOUT))
 		drm_warn(&i915->drm, "PHY %c failed to bring out of Lane reset after %dms.\n",
 			 phy_name(phy), XELPDP_PORT_RESET_END_TIMEOUT);
@@ -2705,7 +2712,7 @@ static void intel_cx0pll_enable(struct intel_encoder *encoder,
 	intel_program_port_clock_ctl(encoder, crtc_state, lane_reversal);
 
 	/* 2. Bring PHY out of reset. */
-	intel_cx0_phy_lane_reset(i915, encoder->port, lane_reversal);
+	intel_cx0_phy_lane_reset(i915, encoder, lane_reversal);
 
 	/*
 	 * 3. Change Phy power state to Ready.
-- 
2.34.1