[PATCH 35/38][SRU][G/H] UBUNTU SAUCE: drm/i915: Factor out a helper to disable the DPCD training pattern
You-Sheng Yang
vicamo.yang at canonical.com
Tue Nov 24 10:43:10 UTC 2020
From: Imre Deak <imre.deak at intel.com>
BugLink: https://bugs.launchpad.net/bugs/1903969
To prepare for a follow-up LTTPR change factor out a helper to disable
the training pattern in DPCD. We'll need to do this for each LTTPR
(without programming the port to output the idle pattern) when training
in LTTPR non-transparent mode.
While at it also move the disable-link-training logic from
intel_dp_set_link_train() to intel_dp_stop_link_train(), since the
latter is the only user of this.
v2:
- Move the disable-link-training logic to intel_dp_stop_link_train()
(Ville)
Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
Signed-off-by: Imre Deak <imre.deak at intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201007170917.1764556-4-imre.deak@intel.com
(cherry picked from commit c43027a9a37541dbdc54e9dca647602175ff27a2
https://anongit.freedesktop.org/git/drm-tip.git)
Signed-off-by: You-Sheng Yang <vicamo.yang at canonical.com>
---
.../drm/i915/display/intel_dp_link_training.c | 33 ++++++++++---------
1 file changed, 17 insertions(+), 16 deletions(-)
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 2658118f18fc..41fb2d2b66ab 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_link_training.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_link_training.c
@@ -85,26 +85,18 @@ intel_dp_set_link_train(struct intel_dp *intel_dp,
u8 dp_train_pat)
{
u8 buf[sizeof(intel_dp->train_set) + 1];
- int ret, len;
+ int len;
intel_dp_program_link_training_pattern(intel_dp, crtc_state,
dp_train_pat);
buf[0] = dp_train_pat;
- if (intel_dp_training_pattern_symbol(dp_train_pat) ==
- DP_TRAINING_PATTERN_DISABLE) {
- /* don't write DP_TRAINING_LANEx_SET on disable */
- len = 1;
- } else {
- /* DP_TRAINING_LANEx_SET follow DP_TRAINING_PATTERN_SET */
- memcpy(buf + 1, intel_dp->train_set, crtc_state->lane_count);
- len = crtc_state->lane_count + 1;
- }
-
- ret = drm_dp_dpcd_write(&intel_dp->aux, DP_TRAINING_PATTERN_SET,
- buf, len);
+ /* DP_TRAINING_LANEx_SET follow DP_TRAINING_PATTERN_SET */
+ memcpy(buf + 1, intel_dp->train_set, crtc_state->lane_count);
+ len = crtc_state->lane_count + 1;
- return ret == len;
+ return drm_dp_dpcd_write(&intel_dp->aux, DP_TRAINING_PATTERN_SET,
+ buf, len) == len;
}
static bool
@@ -397,6 +389,13 @@ intel_dp_link_training_channel_equalization(struct intel_dp *intel_dp,
return channel_eq;
}
+static bool intel_dp_disable_dpcd_training_pattern(struct intel_dp *intel_dp)
+{
+ u8 val = DP_TRAINING_PATTERN_DISABLE;
+
+ return drm_dp_dpcd_write(&intel_dp->aux, DP_TRAINING_PATTERN_SET, &val, 1) == 1;
+}
+
/**
* intel_dp_stop_link_train - stop link training
* @intel_dp: DP struct
@@ -418,8 +417,10 @@ void intel_dp_stop_link_train(struct intel_dp *intel_dp,
{
intel_dp->link_trained = true;
- intel_dp_set_link_train(intel_dp, crtc_state,
- DP_TRAINING_PATTERN_DISABLE);
+ intel_dp_program_link_training_pattern(intel_dp,
+ crtc_state,
+ DP_TRAINING_PATTERN_DISABLE);
+ intel_dp_disable_dpcd_training_pattern(intel_dp);
}
static bool
--
2.29.2
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