[PATCH v2 4/4] hax: drm/i915: Disable TPS4 support to force POST_LT_ADJ_REQ usage

[Ville Syrjala]

From: Ville Syrjälä <ville.syrjala at linux.intel.com>

Disable TPS4 in favor of POST_LT_ADJ_REQ for testing purposes.

Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
---
 drivers/gpu/drm/i915/display/intel_dp_link_training.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/gpu/drm/i915/display/intel_dp_link_training.c b/drivers/gpu/drm/i915/display/intel_dp_link_training.c
index 1a9e28f1ca76..d79c5a11b3fe 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_link_training.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_link_training.c
@@ -794,6 +794,13 @@ static u32 intel_dp_training_pattern(struct intel_dp *intel_dp,
 	source_tps4 = intel_dp_source_supports_tps4(display);
 	sink_tps4 = dp_phy != DP_PHY_DPRX ||
 		    drm_dp_tps4_supported(intel_dp->dpcd);
+
+	/* hax */
+	if (dp_phy == DP_PHY_DPRX &&
+	    drm_dp_post_lt_adj_req_supported(intel_dp->dpcd) &&
+	    crtc_state->port_clock != 810000)
+		sink_tps4 = false;
+
 	if (source_tps4 && sink_tps4) {
 		return DP_TRAINING_PATTERN_4;
 	} else if (crtc_state->port_clock == 810000) {
-- 
2.49.0