[PATCH v6 10/18] drm/i915/alpm: Modify LFPS cycle count for DP ALPM

[Animesh Manna]

For DP minimum LFPS count is set to minimum 16.

Cc: Jouni Högander <jouni.hogan...@intel.com>
Signed-off-by: Animesh Manna <animesh.ma...@intel.com>
---
 drivers/gpu/drm/i915/display/intel_alpm.c | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_alpm.c 
b/drivers/gpu/drm/i915/display/intel_alpm.c
index 14ecb27095b2..22ed341763fa 100644
--- a/drivers/gpu/drm/i915/display/intel_alpm.c
+++ b/drivers/gpu/drm/i915/display/intel_alpm.c
@@ -24,7 +24,8 @@
                                (SILENCE_PERIOD_MAX_TIME -      \
                                 SILENCE_PERIOD_MIN_TIME) / 2)
 
-#define LFPS_CYCLE_COUNT 10
+#define LFPS_CYCLE_COUNT       10
+#define LFPS_CYCLE_COUNT_DP    16
 
 bool intel_alpm_aux_wake_supported(struct intel_dp *intel_dp)
 {
@@ -121,10 +122,19 @@ static int get_lfps_cycle_time(const struct 
intel_crtc_state *crtc_state)
        return tlfps_cycle_min +  (tlfps_cycle_max - tlfps_cycle_min) / 2;
 }
 
+static int get_lfps_cycle_count(const struct intel_crtc_state *crtc_state)
+{
+       /* External DP uses a minimum of 16 LFPS cycles. */
+       if (!intel_crtc_has_type(crtc_state, INTEL_OUTPUT_EDP))
+               return LFPS_CYCLE_COUNT_DP;
+
+       return LFPS_CYCLE_COUNT;
+}
+
 static int get_lfps_half_cycle_clocks(const struct intel_crtc_state 
*crtc_state)
 {
        return get_lfps_cycle_time(crtc_state) * crtc_state->port_clock / 1000 /
-               1000 / (2 * LFPS_CYCLE_COUNT);
+               1000 / (2 * get_lfps_cycle_count(crtc_state));
 }
 
 #define ML_PHY_LOCK_LEN                252
@@ -779,7 +789,7 @@ void intel_alpm_port_configure(struct intel_dp *intel_dp,
                        PORT_ALPM_CTL_MAX_PHY_SWING_HOLD(0) |
                        PORT_ALPM_CTL_SILENCE_PERIOD(
                                
crtc_state->alpm_state.silence_period_sym_clocks);
-               lfps_ctl_val = 
PORT_ALPM_LFPS_CTL_LFPS_CYCLE_COUNT(LFPS_CYCLE_COUNT) |
+               lfps_ctl_val = 
PORT_ALPM_LFPS_CTL_LFPS_CYCLE_COUNT(get_lfps_cycle_count(crtc_state)) |
                        PORT_ALPM_LFPS_CTL_LFPS_HALF_CYCLE_DURATION(
                                
crtc_state->alpm_state.lfps_half_cycle_num_of_syms) |
                        PORT_ALPM_LFPS_CTL_FIRST_LFPS_HALF_CYCLE_DURATION(
-- 
2.29.0