[PATCH 5/8] drm/i915/alpm: Auxless wake time calculation for Xe3p

[Animesh Manna <animesh.manna@intel.com>]

Add support for auxless waketime calculation for DP2.1 ALPM
as dependent parameter got changed.

Cc: Jouni Högander <jouni.hogander@intel.com>
Signed-off-by: Animesh Manna <animesh.manna@intel.com>
---
 drivers/gpu/drm/i915/display/intel_alpm.c | 78 +++++++++++++++++++----
 1 file changed, 67 insertions(+), 11 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_alpm.c b/drivers/gpu/drm/i915/display/intel_alpm.c
index 0f6b15bca3be..ee5b1e3d79d2 100644
--- a/drivers/gpu/drm/i915/display/intel_alpm.c
+++ b/drivers/gpu/drm/i915/display/intel_alpm.c
@@ -96,6 +96,66 @@ static int get_lfps_half_cycle_clocks(const struct intel_crtc_state *crtc_state)
 		1000 / (2 * LFPS_CYCLE_COUNT);
 }
 
+static int get_tphy2_p2_to_p0(struct intel_dp *intel_dp)
+{
+	struct intel_display *display = to_intel_display(intel_dp);
+
+	return DISPLAY_VER(display) >= 35 ? (40 * 1000) : (12 * 1000);
+}
+
+static int get_establishment_period(struct intel_dp *intel_dp,
+				    const struct intel_crtc_state *crtc_state)
+{
+	int port_clock = crtc_state->port_clock;
+	int t1 = 50 * 1000;
+	int tps4 = (port_clock >= 1000000) ? (396 * 32) : (252 * 10);
+	int tml_phy_lock = 1000 * 1000 * tps4 / port_clock / 10;
+	int lttpr_count = 0;
+	int establishment_period;
+	int tcds;
+
+	if (!intel_dp_is_edp(intel_dp)) {
+		lttpr_count = drm_dp_lttpr_count(intel_dp->lttpr_common_caps);
+		tcds = 7 * tml_phy_lock;
+	} else {
+		tcds = (7 + DIV_ROUND_UP(6500, tml_phy_lock) + 1) * tml_phy_lock;
+	}
+
+	if (lttpr_count) {
+		int tlw = 13000;
+		int tcs = 10000;
+		int tlfps_period = get_lfps_cycle_time(crtc_state);
+		int tdcs = (SILENCE_PERIOD_TIME + t1 + tcs +
+			    (lttpr_count - 1) * (tlw + tlfps_period));
+		int tacds = 70000;
+		int tds = (lttpr_count - 1) * 7 * tml_phy_lock;
+
+		/* tdrl is same as tcds*/
+		establishment_period = tlw + tlfps_period + tdcs + tacds + tds + tcds;
+	} else {
+		/* TODO: Add a check for data realign by DPCD 0x116[3] */
+
+		establishment_period = (SILENCE_PERIOD_TIME + t1 + tcds);
+	}
+
+	return establishment_period;
+}
+
+static int get_switch_to_active(int port_clock)
+{
+	int switch_to_active;
+
+	if (port_clock >= 1000000) {
+		int symbol_clock = port_clock / intel_dp_link_symbol_size(port_clock);
+
+		switch_to_active = 32 * DIV_ROUND_UP((396 + 3 + 64), symbol_clock);
+	} else {
+		switch_to_active = 0;
+	}
+
+	return switch_to_active;
+}
+
 /*
  * AUX-Less Wake Time = CEILING( ((PHY P2 to P0) + tLFPS_Period, Max+
  * tSilence, Max+ tPHY Establishment + tCDS) / tline)
@@ -115,19 +175,15 @@ static int get_lfps_half_cycle_clocks(const struct intel_crtc_state *crtc_state)
  * tML_PHY_LOCK = TPS4 Length * ( 10 / (Link Rate in MHz) )
  * TPS4 Length = 252 Symbols
  */
-static int _lnl_compute_aux_less_wake_time(const struct intel_crtc_state *crtc_state)
+static int _lnl_compute_aux_less_wake_time(struct intel_dp *intel_dp,
+					   const struct intel_crtc_state *crtc_state)
 {
-	int tphy2_p2_to_p0 = 12 * 1000;
-	int t1 = 50 * 1000;
-	int tps4 = 252;
-	/* port_clock is link rate in 10kbit/s units */
-	int tml_phy_lock = 1000 * 1000 * tps4 / crtc_state->port_clock;
-	int num_ml_phy_lock = 7 + DIV_ROUND_UP(6500, tml_phy_lock) + 1;
-	int t2 = num_ml_phy_lock * tml_phy_lock;
-	int tcds = 1 * t2;
+	int tphy2_p2_to_p0 = get_tphy2_p2_to_p0(intel_dp);
+	int establishment_period = get_establishment_period(intel_dp, crtc_state);
+	int switch_to_active = get_switch_to_active(crtc_state->port_clock);
 
 	return DIV_ROUND_UP(tphy2_p2_to_p0 + get_lfps_cycle_time(crtc_state) +
-			    SILENCE_PERIOD_TIME + t1 + tcds, 1000);
+			    establishment_period + switch_to_active, 1000);
 }
 
 static int
@@ -139,7 +195,7 @@ _lnl_compute_aux_less_alpm_params(struct intel_dp *intel_dp,
 		lfps_half_cycle;
 
 	aux_less_wake_time =
-		_lnl_compute_aux_less_wake_time(crtc_state);
+		_lnl_compute_aux_less_wake_time(intel_dp, crtc_state);
 	aux_less_wake_lines = intel_usecs_to_scanlines(&crtc_state->hw.adjusted_mode,
 						       aux_less_wake_time);
 	silence_period = get_silence_period_symbols(crtc_state);
-- 
2.29.0