[PATCHv2 3/3] drm/i915/dp: Include the time taken by AUX Tx for timeout

Arun R Murthy arun.r.murthy at intel.com
Tue Sep 24 06:36:16 UTC 2024


As per DP spec the timeout for LANE_CHANNEL_EQ_DONE is 400ms. But this
timeout value is exclusively for the Aux RD Interval and excludes the
time consumed for the AUX Tx (i.e reading/writing FFE presets). Add
another 50ms for these AUX Tx to the 400ms timeout.
Ref: "Figure 3-52: 128b132b DP DPTC LANEx_CHANNEL_EQ_DONE Sequence" of
DP2.1a spec.

Co-developed-by: Srikanth V NagaVenkata <nagavenkata.srikanth.v at intel.com>
Signed-off-by: Arun R Murthy <arun.r.murthy at intel.com>
Reviewed-by: Suraj Kandpal <suraj.kandpal at intel.com>
Acked-by: Jani Nikula <jani.nikula at intel.com>
---
 drivers/gpu/drm/i915/display/intel_dp_link_training.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

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 ec6c323a49c0..ddf91b3533a4 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_link_training.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_link_training.c
@@ -1414,7 +1414,7 @@ intel_dp_128b132b_lane_eq(struct intel_dp *intel_dp,
 	}
 
 	/* Time budget for the LANEx_EQ_DONE Sequence */
-	deadline = jiffies + msecs_to_jiffies_timeout(400);
+	deadline = jiffies + msecs_to_jiffies_timeout(450);
 
 	for (try = 0; try < max_tries; try++) {
 		fsleep(delay_us);
-- 
2.25.1



More information about the Intel-gfx mailing list