drm/i915/cx0: Program vswing only for owned lanes

According to the BSpec, voltage swing programming should be done for
owned PHY lanes. Do not program a not-owned PHY lane.

BSpec: 74103, 74104
Reviewed-by: Mika Kahola <mika.kahola@intel.com>
Signed-off-by: Gustavo Sousa <gustavo.sousa@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230814131331.69516-5-gustavo.sousa@intel.com

drivers/gpu/drm/i915/display/intel_cx0_phy.c

@@ -375,6 +375,7 @@ void intel_cx0_phy_set_signal_levels(struct intel_encoder *encoder,
 	struct drm_i915_private *i915 = to_i915(encoder->base.dev);
 	const struct intel_ddi_buf_trans *trans;
 	enum phy phy = intel_port_to_phy(i915, encoder->port);
+	u8 owned_lane_mask = intel_cx0_get_owned_lane_mask(i915, encoder);
 	intel_wakeref_t wakeref;
 	int n_entries, ln;
 
@@ -387,13 +388,13 @@ void intel_cx0_phy_set_signal_levels(struct intel_encoder *encoder,
 	}
 
 	if (intel_is_c10phy(i915, phy)) {
-		intel_cx0_rmw(i915, encoder->port, INTEL_CX0_BOTH_LANES, PHY_C10_VDR_CONTROL(1),
+		intel_cx0_rmw(i915, encoder->port, owned_lane_mask, PHY_C10_VDR_CONTROL(1),
 			      0, C10_VDR_CTRL_MSGBUS_ACCESS, MB_WRITE_COMMITTED);
-		intel_cx0_rmw(i915, encoder->port, INTEL_CX0_BOTH_LANES, PHY_C10_VDR_CMN(3),
+		intel_cx0_rmw(i915, encoder->port, owned_lane_mask, PHY_C10_VDR_CMN(3),
 			      C10_CMN3_TXVBOOST_MASK,
 			      C10_CMN3_TXVBOOST(intel_c10_get_tx_vboost_lvl(crtc_state)),
 			      MB_WRITE_UNCOMMITTED);
-		intel_cx0_rmw(i915, encoder->port, INTEL_CX0_BOTH_LANES, PHY_C10_VDR_TX(1),
+		intel_cx0_rmw(i915, encoder->port, owned_lane_mask, PHY_C10_VDR_TX(1),
 			      C10_TX1_TERMCTL_MASK,
 			      C10_TX1_TERMCTL(intel_c10_get_tx_term_ctl(crtc_state)),
 			      MB_WRITE_COMMITTED);
@@ -401,32 +402,34 @@ void intel_cx0_phy_set_signal_levels(struct intel_encoder *encoder,
 
 	for (ln = 0; ln < crtc_state->lane_count; ln++) {
 		int level = intel_ddi_level(encoder, crtc_state, ln);
-		int lane, tx;
+		int lane = ln / 2;
+		int tx = ln % 2;
+		u8 lane_mask = lane == 0 ? INTEL_CX0_LANE0 : INTEL_CX0_LANE1;
 
-		lane = ln / 2;
-		tx = ln % 2;
+		if (!(lane_mask & owned_lane_mask))
+			continue;
 
-		intel_cx0_rmw(i915, encoder->port, BIT(lane), PHY_CX0_VDROVRD_CTL(lane, tx, 0),
+		intel_cx0_rmw(i915, encoder->port, lane_mask, PHY_CX0_VDROVRD_CTL(lane, tx, 0),
 			      C10_PHY_OVRD_LEVEL_MASK,
 			      C10_PHY_OVRD_LEVEL(trans->entries[level].snps.pre_cursor),
 			      MB_WRITE_COMMITTED);
-		intel_cx0_rmw(i915, encoder->port, BIT(lane), PHY_CX0_VDROVRD_CTL(lane, tx, 1),
+		intel_cx0_rmw(i915, encoder->port, lane_mask, PHY_CX0_VDROVRD_CTL(lane, tx, 1),
 			      C10_PHY_OVRD_LEVEL_MASK,
 			      C10_PHY_OVRD_LEVEL(trans->entries[level].snps.vswing),
 			      MB_WRITE_COMMITTED);
-		intel_cx0_rmw(i915, encoder->port, BIT(lane), PHY_CX0_VDROVRD_CTL(lane, tx, 2),
+		intel_cx0_rmw(i915, encoder->port, lane_mask, PHY_CX0_VDROVRD_CTL(lane, tx, 2),
 			      C10_PHY_OVRD_LEVEL_MASK,
 			      C10_PHY_OVRD_LEVEL(trans->entries[level].snps.post_cursor),
 			      MB_WRITE_COMMITTED);
 	}
 
 	/* Write Override enables in 0xD71 */
-	intel_cx0_rmw(i915, encoder->port, INTEL_CX0_BOTH_LANES, PHY_C10_VDR_OVRD,
+	intel_cx0_rmw(i915, encoder->port, owned_lane_mask, PHY_C10_VDR_OVRD,
 		      0, PHY_C10_VDR_OVRD_TX1 | PHY_C10_VDR_OVRD_TX2,
 		      MB_WRITE_COMMITTED);
 
 	if (intel_is_c10phy(i915, phy))
-		intel_cx0_rmw(i915, encoder->port, INTEL_CX0_BOTH_LANES, PHY_C10_VDR_CONTROL(1),
+		intel_cx0_rmw(i915, encoder->port, owned_lane_mask, PHY_C10_VDR_CONTROL(1),
 			      0, C10_VDR_CTRL_UPDATE_CFG, MB_WRITE_COMMITTED);
 
 	intel_cx0_phy_transaction_end(encoder, wakeref);