This is a note to let you know that I've just added the patch titled
drm/amd/display: Fix 128b132b link loss handling
to the 6.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
drm-amd-display-fix-128b132b-link-loss-handling.patch
and it can be found in the queue-6.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From ed83fe2abcace898fdec5c2ba0455703178ac9a3 Mon Sep 17 00:00:00 2001
From: Ilya Bakoulin <ilya.bakoulin@xxxxxxx>
Date: Wed, 7 Jun 2023 16:49:45 -0400
Subject: drm/amd/display: Fix 128b132b link loss handling
From: Ilya Bakoulin <ilya.bakoulin@xxxxxxx>
commit ed83fe2abcace898fdec5c2ba0455703178ac9a3 upstream.
[Why]
We don't check 128b132b-specific bits in LANE_ALIGN_STATUS_UPDATED DPCD
registers when parsing link loss status, which can cause us to miss a
link loss notification from some sinks.
[How]
Add a 128b132b-specific status bit check.
Cc: stable@xxxxxxxxxxxxxxx # 6.3+
Reviewed-by: Wenjing Liu <wenjing.liu@xxxxxxx>
Acked-by: Hamza Mahfooz <hamza.mahfooz@xxxxxxx>
Signed-off-by: Ilya Bakoulin <ilya.bakoulin@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
.../display/dc/link/protocols/link_dp_irq_handler.c | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_irq_handler.c b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_irq_handler.c
index ba95facc4ee8..b1b11eb0f9bb 100644
--- a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_irq_handler.c
+++ b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_irq_handler.c
@@ -82,8 +82,15 @@ bool dp_parse_link_loss_status(
}
/* Check interlane align.*/
- if (sink_status_changed ||
- !hpd_irq_dpcd_data->bytes.lane_status_updated.bits.INTERLANE_ALIGN_DONE) {
+ if (link_dp_get_encoding_format(&link->cur_link_settings) == DP_128b_132b_ENCODING &&
+ (!hpd_irq_dpcd_data->bytes.lane_status_updated.bits.EQ_INTERLANE_ALIGN_DONE_128b_132b ||
+ !hpd_irq_dpcd_data->bytes.lane_status_updated.bits.CDS_INTERLANE_ALIGN_DONE_128b_132b)) {
+ sink_status_changed = true;
+ } else if (!hpd_irq_dpcd_data->bytes.lane_status_updated.bits.INTERLANE_ALIGN_DONE) {
+ sink_status_changed = true;
+ }
+
+ if (sink_status_changed) {
DC_LOG_HW_HPD_IRQ("%s: Link Status changed.\n", __func__);
--
2.41.0
Patches currently in stable-queue which might be from ilya.bakoulin@xxxxxxx are
queue-6.4/drm-amd-display-fix-128b132b-link-loss-handling.patch
