The 128b/132b channel coding link training uses more straightforward TX FFE preset values.
v2: Fix UHBR rate checks, use intel_dp_is_uhbr() helper
Signed-off-by: Jani Nikula jani.nikula@intel.com --- drivers/gpu/drm/i915/display/intel_ddi.c | 13 ++- .../drm/i915/display/intel_dp_link_training.c | 86 +++++++++++++------ 2 files changed, 70 insertions(+), 29 deletions(-)
diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c b/drivers/gpu/drm/i915/display/intel_ddi.c index d2b96b2efdfe..5805bdd6e1f2 100644 --- a/drivers/gpu/drm/i915/display/intel_ddi.c +++ b/drivers/gpu/drm/i915/display/intel_ddi.c @@ -1398,11 +1398,16 @@ static int translate_signal_level(struct intel_dp *intel_dp, static int intel_ddi_dp_level(struct intel_dp *intel_dp, const struct intel_crtc_state *crtc_state) { - u8 train_set = intel_dp->train_set[0]; - u8 signal_levels = train_set & (DP_TRAIN_VOLTAGE_SWING_MASK | - DP_TRAIN_PRE_EMPHASIS_MASK); + if (intel_dp_is_uhbr(crtc_state)) { + /* FIXME: We'll want independent presets for each lane. */ + return intel_dp->train_set[0] & DP_TX_FFE_PRESET_VALUE_MASK; + } else { + u8 train_set = intel_dp->train_set[0]; + u8 signal_levels = train_set & (DP_TRAIN_VOLTAGE_SWING_MASK | + DP_TRAIN_PRE_EMPHASIS_MASK);
- return translate_signal_level(intel_dp, signal_levels); + return translate_signal_level(intel_dp, signal_levels); + } }
static void 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 4f116cd32846..c10f165d1aa2 100644 --- a/drivers/gpu/drm/i915/display/intel_dp_link_training.c +++ b/drivers/gpu/drm/i915/display/intel_dp_link_training.c @@ -301,6 +301,24 @@ static u8 intel_dp_phy_preemph_max(struct intel_dp *intel_dp, return preemph_max; }
+static void intel_dp_128b132b_adjust_train(struct intel_dp *intel_dp, + const struct intel_crtc_state *crtc_state, + const u8 link_status[DP_LINK_STATUS_SIZE]) +{ + int lane; + u8 tx_ffe = 0; + + /* + * FIXME: We'll want independent presets for each lane. See also + * intel_ddi_dp_level() and intel_snps_phy_ddi_vswing_sequence(). + */ + for (lane = 0; lane < crtc_state->lane_count; lane++) + tx_ffe = max(tx_ffe, drm_dp_get_adjust_tx_ffe_preset(link_status, lane)); + + for (lane = 0; lane < crtc_state->lane_count; lane++) + intel_dp->train_set[lane] = tx_ffe; +} + void intel_dp_get_adjust_train(struct intel_dp *intel_dp, const struct intel_crtc_state *crtc_state, @@ -313,6 +331,11 @@ intel_dp_get_adjust_train(struct intel_dp *intel_dp, u8 voltage_max; u8 preemph_max;
+ if (intel_dp_is_uhbr(crtc_state)) { + intel_dp_128b132b_adjust_train(intel_dp, crtc_state, link_status); + return; + } + for (lane = 0; lane < crtc_state->lane_count; lane++) { v = max(v, drm_dp_get_adjust_request_voltage(link_status, lane)); p = max(p, drm_dp_get_adjust_request_pre_emphasis(link_status, lane)); @@ -402,14 +425,21 @@ void intel_dp_set_signal_levels(struct intel_dp *intel_dp, u8 train_set = intel_dp->train_set[0]; char phy_name[10];
- drm_dbg_kms(&dev_priv->drm, "Using vswing level %d%s, pre-emphasis level %d%s, at %s\n", - train_set & DP_TRAIN_VOLTAGE_SWING_MASK, - train_set & DP_TRAIN_MAX_SWING_REACHED ? " (max)" : "", - (train_set & DP_TRAIN_PRE_EMPHASIS_MASK) >> - DP_TRAIN_PRE_EMPHASIS_SHIFT, - train_set & DP_TRAIN_MAX_PRE_EMPHASIS_REACHED ? - " (max)" : "", - intel_dp_phy_name(dp_phy, phy_name, sizeof(phy_name))); + if (intel_dp_is_uhbr(crtc_state)) { + /* FIXME: We'll want independent presets for each lane. */ + drm_dbg_kms(&dev_priv->drm, "%s: Using 128b/132b TX FFE preset %u\n", + intel_dp_phy_name(dp_phy, phy_name, sizeof(phy_name)), + train_set & DP_TX_FFE_PRESET_VALUE_MASK); + } else { + drm_dbg_kms(&dev_priv->drm, "%s: Using 8b/10b vswing level %d%s, pre-emphasis level %d%s\n", + intel_dp_phy_name(dp_phy, phy_name, sizeof(phy_name)), + train_set & DP_TRAIN_VOLTAGE_SWING_MASK, + train_set & DP_TRAIN_MAX_SWING_REACHED ? " (max)" : "", + (train_set & DP_TRAIN_PRE_EMPHASIS_MASK) >> + DP_TRAIN_PRE_EMPHASIS_SHIFT, + train_set & DP_TRAIN_MAX_PRE_EMPHASIS_REACHED ? + " (max)" : ""); + }
if (intel_dp_phy_is_downstream_of_source(intel_dp, dp_phy)) intel_dp->set_signal_levels(intel_dp, crtc_state); @@ -565,18 +595,21 @@ intel_dp_link_training_clock_recovery(struct intel_dp *intel_dp, return true; }
- if (voltage_tries == 5) { - drm_dbg_kms(&i915->drm, - "Same voltage tried 5 times\n"); - return false; - } + /* FIXME: 128b/132b needs better abstractions here. */ + if (!intel_dp_is_uhbr(crtc_state)) { + if (voltage_tries == 5) { + drm_dbg_kms(&i915->drm, + "Same voltage tried 5 times\n"); + return false; + }
- if (max_vswing_reached) { - drm_dbg_kms(&i915->drm, "Max Voltage Swing reached\n"); - return false; - } + if (max_vswing_reached) { + drm_dbg_kms(&i915->drm, "Max Voltage Swing reached\n"); + return false; + }
- voltage = intel_dp->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK; + voltage = intel_dp->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK; + }
/* Update training set as requested by target */ intel_dp_get_adjust_train(intel_dp, crtc_state, dp_phy, @@ -587,14 +620,17 @@ intel_dp_link_training_clock_recovery(struct intel_dp *intel_dp, return false; }
- if ((intel_dp->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK) == - voltage) - ++voltage_tries; - else - voltage_tries = 1; + /* FIXME: 128b/132b needs better abstractions here. */ + if (!intel_dp_is_uhbr(crtc_state)) { + if ((intel_dp->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK) == + voltage) + ++voltage_tries; + else + voltage_tries = 1;
- if (intel_dp_link_max_vswing_reached(intel_dp, crtc_state)) - max_vswing_reached = true; + if (intel_dp_link_max_vswing_reached(intel_dp, crtc_state)) + max_vswing_reached = true; + }
} drm_err(&i915->drm,