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authorVille Syrjälä <ville.syrjala@linux.intel.com>2025-07-10 23:17:15 +0300
committerVille Syrjälä <ville.syrjala@linux.intel.com>2025-07-17 19:42:05 +0300
commitb840bb0b7ec279660002afc83217c435e6896870 (patch)
tree21c416f2be06cd1045a6a10e7c8a770d42466e13 /drivers/gpu/drm/i915/display/intel_dp_link_training.c
parent11fab5a2a1ad78d12f23cee209f1705f6d7ca281 (diff)
drm/i915/dp: Have intel_dp_get_adjust_train() tell us if anything changed
In order to implement the POST_LT_ADJ_REQ sequence we need to know whether the sink actually requested a changed to the vswing/pre-emph values. Tested-by: Imre Deak <imre.deak@intel.com> Reviewed-by: Imre Deak <imre.deak@intel.com> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20250710201718.25310-5-ville.syrjala@linux.intel.com
Diffstat (limited to 'drivers/gpu/drm/i915/display/intel_dp_link_training.c')
-rw-r--r--drivers/gpu/drm/i915/display/intel_dp_link_training.c18
1 files changed, 13 insertions, 5 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 322a26c1910c..57b9dc52a98d 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_link_training.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_link_training.c
@@ -478,12 +478,13 @@ static u8 intel_dp_get_lane_adjust_train(struct intel_dp *intel_dp,
_TRAIN_REQ_TX_FFE_ARGS(link_status, 2), \
_TRAIN_REQ_TX_FFE_ARGS(link_status, 3)
-void
+bool
intel_dp_get_adjust_train(struct intel_dp *intel_dp,
const struct intel_crtc_state *crtc_state,
enum drm_dp_phy dp_phy,
const u8 link_status[DP_LINK_STATUS_SIZE])
{
+ bool changed = false;
int lane;
if (intel_dp_is_uhbr(crtc_state)) {
@@ -502,10 +503,17 @@ intel_dp_get_adjust_train(struct intel_dp *intel_dp,
TRAIN_REQ_PREEMPH_ARGS(link_status));
}
- for (lane = 0; lane < 4; lane++)
- intel_dp->train_set[lane] =
- intel_dp_get_lane_adjust_train(intel_dp, crtc_state,
- dp_phy, link_status, lane);
+ for (lane = 0; lane < 4; lane++) {
+ u8 new = intel_dp_get_lane_adjust_train(intel_dp, crtc_state,
+ dp_phy, link_status, lane);
+ if (intel_dp->train_set[lane] == new)
+ continue;
+
+ intel_dp->train_set[lane] = new;
+ changed = true;
+ }
+
+ return changed;
}
static int intel_dp_training_pattern_set_reg(struct intel_dp *intel_dp,