[PATCH 07/14] drm/amd/display: minor dp link training refactor

Stylon Wang stylon.wang at amd.com
Fri May 7 14:58:15 UTC 2021


From: Wenjing Liu <wenjing.liu at amd.com>

[how]
The change includes some dp link training refactors:
1. break down is_ch_eq_done to checking individual conditions in
its own function.
2. update dpcd_set_training_pattern to take in dc_dp_training_pattern
as input.
3. moving lttpr mode struct definition into link_service_types.h

Signed-off-by: Wenjing Liu <wenjing.liu at amd.com>
Reviewed-by: George Shen <George.Shen at amd.com>
Acked-by: Stylon Wang <stylon.wang at amd.com>
---
 .../gpu/drm/amd/display/dc/core/dc_link_dp.c  | 124 ++++++++++--------
 drivers/gpu/drm/amd/display/dc/dc_dp_types.h  |   1 +
 drivers/gpu/drm/amd/display/dc/dc_link.h      |   6 -
 .../amd/display/include/link_service_types.h  |   6 +
 4 files changed, 77 insertions(+), 60 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c
index de75e8581078..27c5d49a7bc1 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c
@@ -108,10 +108,50 @@ static void wait_for_training_aux_rd_interval(
 		wait_in_micro_secs);
 }
 
+static enum dpcd_training_patterns
+	dc_dp_training_pattern_to_dpcd_training_pattern(
+	struct dc_link *link,
+	enum dc_dp_training_pattern pattern)
+{
+	enum dpcd_training_patterns dpcd_tr_pattern =
+	DPCD_TRAINING_PATTERN_VIDEOIDLE;
+
+	switch (pattern) {
+	case DP_TRAINING_PATTERN_SEQUENCE_1:
+		dpcd_tr_pattern = DPCD_TRAINING_PATTERN_1;
+		break;
+	case DP_TRAINING_PATTERN_SEQUENCE_2:
+		dpcd_tr_pattern = DPCD_TRAINING_PATTERN_2;
+		break;
+	case DP_TRAINING_PATTERN_SEQUENCE_3:
+		dpcd_tr_pattern = DPCD_TRAINING_PATTERN_3;
+		break;
+	case DP_TRAINING_PATTERN_SEQUENCE_4:
+		dpcd_tr_pattern = DPCD_TRAINING_PATTERN_4;
+		break;
+	case DP_TRAINING_PATTERN_VIDEOIDLE:
+		dpcd_tr_pattern = DPCD_TRAINING_PATTERN_VIDEOIDLE;
+		break;
+	default:
+		ASSERT(0);
+		DC_LOG_HW_LINK_TRAINING("%s: Invalid HW Training pattern: %d\n",
+			__func__, pattern);
+		break;
+	}
+
+	return dpcd_tr_pattern;
+}
+
 static void dpcd_set_training_pattern(
 	struct dc_link *link,
-	union dpcd_training_pattern dpcd_pattern)
+	enum dc_dp_training_pattern training_pattern)
 {
+	union dpcd_training_pattern dpcd_pattern = { {0} };
+
+	dpcd_pattern.v1_4.TRAINING_PATTERN_SET =
+			dc_dp_training_pattern_to_dpcd_training_pattern(
+					link, training_pattern);
+
 	core_link_write_dpcd(
 		link,
 		DP_TRAINING_PATTERN_SET,
@@ -240,37 +280,6 @@ static void dpcd_set_link_settings(
 	}
 }
 
-static enum dpcd_training_patterns
-	dc_dp_training_pattern_to_dpcd_training_pattern(
-	struct dc_link *link,
-	enum dc_dp_training_pattern pattern)
-{
-	enum dpcd_training_patterns dpcd_tr_pattern =
-	DPCD_TRAINING_PATTERN_VIDEOIDLE;
-
-	switch (pattern) {
-	case DP_TRAINING_PATTERN_SEQUENCE_1:
-		dpcd_tr_pattern = DPCD_TRAINING_PATTERN_1;
-		break;
-	case DP_TRAINING_PATTERN_SEQUENCE_2:
-		dpcd_tr_pattern = DPCD_TRAINING_PATTERN_2;
-		break;
-	case DP_TRAINING_PATTERN_SEQUENCE_3:
-		dpcd_tr_pattern = DPCD_TRAINING_PATTERN_3;
-		break;
-	case DP_TRAINING_PATTERN_SEQUENCE_4:
-		dpcd_tr_pattern = DPCD_TRAINING_PATTERN_4;
-		break;
-	default:
-		ASSERT(0);
-		DC_LOG_HW_LINK_TRAINING("%s: Invalid HW Training pattern: %d\n",
-			__func__, pattern);
-		break;
-	}
-
-	return dpcd_tr_pattern;
-}
-
 static uint8_t dc_dp_initialize_scrambling_data_symbols(
 	struct dc_link *link,
 	enum dc_dp_training_pattern pattern)
@@ -433,20 +442,30 @@ static bool is_cr_done(enum dc_lane_count ln_count,
 }
 
 static bool is_ch_eq_done(enum dc_lane_count ln_count,
-	union lane_status *dpcd_lane_status,
-	union lane_align_status_updated *lane_status_updated)
+		union lane_status *dpcd_lane_status)
 {
+	bool done = true;
 	uint32_t lane;
-	if (!lane_status_updated->bits.INTERLANE_ALIGN_DONE)
-		return false;
-	else {
-		for (lane = 0; lane < (uint32_t)(ln_count); lane++) {
-			if (!dpcd_lane_status[lane].bits.SYMBOL_LOCKED_0 ||
-				!dpcd_lane_status[lane].bits.CHANNEL_EQ_DONE_0)
-				return false;
-		}
-	}
-	return true;
+	for (lane = 0; lane < (uint32_t)(ln_count); lane++)
+		if (!dpcd_lane_status[lane].bits.CHANNEL_EQ_DONE_0)
+			done = false;
+	return done;
+}
+
+static bool is_symbol_locked(enum dc_lane_count ln_count,
+		union lane_status *dpcd_lane_status)
+{
+	bool locked = true;
+	uint32_t lane;
+	for (lane = 0; lane < (uint32_t)(ln_count); lane++)
+		if (!dpcd_lane_status[lane].bits.SYMBOL_LOCKED_0)
+			locked = false;
+	return locked;
+}
+
+static inline bool is_interlane_aligned(union lane_align_status_updated align_status)
+{
+	return align_status.bits.INTERLANE_ALIGN_DONE == 1;
 }
 
 static void update_drive_settings(
@@ -848,10 +867,9 @@ static bool perform_post_lt_adj_req_sequence(
 			if (!is_cr_done(lane_count, dpcd_lane_status))
 				return false;
 
-			if (!is_ch_eq_done(
-				lane_count,
-				dpcd_lane_status,
-				&dpcd_lane_status_updated))
+			if (!is_ch_eq_done(lane_count, dpcd_lane_status) ||
+					!is_symbol_locked(lane_count, dpcd_lane_status) ||
+					!is_interlane_aligned(dpcd_lane_status_updated))
 				return false;
 
 			for (lane = 0; lane < (uint32_t)(lane_count); lane++) {
@@ -1005,9 +1023,9 @@ static enum link_training_result perform_channel_equalization_sequence(
 			return LINK_TRAINING_EQ_FAIL_CR;
 
 		/* 6. check CHEQ done*/
-		if (is_ch_eq_done(lane_count,
-			dpcd_lane_status,
-			&dpcd_lane_status_updated))
+		if (is_ch_eq_done(lane_count, dpcd_lane_status) &&
+				is_symbol_locked(lane_count, dpcd_lane_status) &&
+				is_interlane_aligned(dpcd_lane_status_updated))
 			return LINK_TRAINING_SUCCESS;
 
 		/* 7. update VS/PE/PC2 in lt_settings*/
@@ -1569,7 +1587,6 @@ enum link_training_result dc_link_dp_perform_link_training(
 {
 	enum link_training_result status = LINK_TRAINING_SUCCESS;
 	struct link_training_settings lt_settings;
-	union dpcd_training_pattern dpcd_pattern = { { 0 } };
 
 	bool fec_enable;
 	uint8_t repeater_cnt;
@@ -1635,8 +1652,7 @@ enum link_training_result dc_link_dp_perform_link_training(
 	}
 
 	/* 3. set training not in progress*/
-	dpcd_pattern.v1_4.TRAINING_PATTERN_SET = DPCD_TRAINING_PATTERN_VIDEOIDLE;
-	dpcd_set_training_pattern(link, dpcd_pattern);
+	dpcd_set_training_pattern(link, DP_TRAINING_PATTERN_VIDEOIDLE);
 	if ((status == LINK_TRAINING_SUCCESS) || !skip_video_pattern) {
 		status = perform_link_training_int(link,
 				&lt_settings,
diff --git a/drivers/gpu/drm/amd/display/dc/dc_dp_types.h b/drivers/gpu/drm/amd/display/dc/dc_dp_types.h
index cc6fb838420e..fcfde2e04292 100644
--- a/drivers/gpu/drm/amd/display/dc/dc_dp_types.h
+++ b/drivers/gpu/drm/amd/display/dc/dc_dp_types.h
@@ -95,6 +95,7 @@ enum dc_dp_training_pattern {
 	DP_TRAINING_PATTERN_SEQUENCE_2,
 	DP_TRAINING_PATTERN_SEQUENCE_3,
 	DP_TRAINING_PATTERN_SEQUENCE_4,
+	DP_TRAINING_PATTERN_VIDEOIDLE,
 };
 
 struct dc_link_settings {
diff --git a/drivers/gpu/drm/amd/display/dc/dc_link.h b/drivers/gpu/drm/amd/display/dc/dc_link.h
index 5196df1ebad1..6398ab486506 100644
--- a/drivers/gpu/drm/amd/display/dc/dc_link.h
+++ b/drivers/gpu/drm/amd/display/dc/dc_link.h
@@ -36,12 +36,6 @@ enum dc_link_fec_state {
 	dc_link_fec_enabled
 };
 
-enum lttpr_mode {
-	LTTPR_MODE_NON_LTTPR,
-	LTTPR_MODE_TRANSPARENT,
-	LTTPR_MODE_NON_TRANSPARENT,
-};
-
 struct dc_link_status {
 	bool link_active;
 	struct dpcd_caps *dpcd_caps;
diff --git a/drivers/gpu/drm/amd/display/include/link_service_types.h b/drivers/gpu/drm/amd/display/include/link_service_types.h
index 5a250f41004f..73ada16658aa 100644
--- a/drivers/gpu/drm/amd/display/include/link_service_types.h
+++ b/drivers/gpu/drm/amd/display/include/link_service_types.h
@@ -72,6 +72,12 @@ enum link_training_result {
 	LINK_TRAINING_ABORT,
 };
 
+enum lttpr_mode {
+	LTTPR_MODE_NON_LTTPR,
+	LTTPR_MODE_TRANSPARENT,
+	LTTPR_MODE_NON_TRANSPARENT,
+};
+
 struct link_training_settings {
 	struct dc_link_settings link_settings;
 	struct dc_lane_settings lane_settings[LANE_COUNT_DP_MAX];
-- 
2.25.1



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