This is a note to let you know that I've just added the patch titled
drm/amd/display: Require immediate flip support for DCN3.1 planes
to the 5.14-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-require-immediate-flip-support-for-dcn3.1-planes.patch
and it can be found in the queue-5.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 672437486ee9da3ed0e774937e6d0dd570921b39 Mon Sep 17 00:00:00 2001
From: Nicholas Kazlauskas <nicholas.kazlauskas@xxxxxxx>
Date: Wed, 29 Sep 2021 16:22:53 -0400
Subject: drm/amd/display: Require immediate flip support for DCN3.1 planes
From: Nicholas Kazlauskas <nicholas.kazlauskas@xxxxxxx>
commit 672437486ee9da3ed0e774937e6d0dd570921b39 upstream.
[Why]
Immediate flip can be enabled dynamically and has higher BW requirements
when validating which voltage mode to use.
If we validate when it's not set then potentially DCFCLK will be too low
and we will underflow.
[How]
DM always requires support so always require it as part of DML input
parameters.
This can't be enabled unconditionally on older ASIC because it blocks
some expected modes so only target DCN3.1 for now.
Reviewed-by: Dmytro Laktyushkin <Dmytro.Laktyushkin@xxxxxxx>
Acked-by: Agustin Gutierrez Sanchez <agustin.gutierrez@xxxxxxx>
Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@xxxxxxx>
Tested-by: Daniel Wheeler <daniel.wheeler@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/amd/display/dc/dcn31/dcn31_resource.c | 7 +++++++
1 file changed, 7 insertions(+)
--- a/drivers/gpu/drm/amd/display/dc/dcn31/dcn31_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn31/dcn31_resource.c
@@ -1591,6 +1591,13 @@ static int dcn31_populate_dml_pipes_from
pipe = &res_ctx->pipe_ctx[i];
timing = &pipe->stream->timing;
+ /*
+ * Immediate flip can be set dynamically after enabling the plane.
+ * We need to require support for immediate flip or underflow can be
+ * intermittently experienced depending on peak b/w requirements.
+ */
+ pipes[pipe_cnt].pipe.src.immediate_flip = true;
+
pipes[pipe_cnt].pipe.src.unbounded_req_mode = false;
pipes[pipe_cnt].pipe.src.gpuvm = true;
pipes[pipe_cnt].pipe.src.dcc_fraction_of_zs_req_luma = 0;
Patches currently in stable-queue which might be from nicholas.kazlauskas@xxxxxxx are
queue-5.14/drm-amd-display-require-immediate-flip-support-for-dcn3.1-planes.patch
queue-5.14/drm-amd-display-fallback-to-clocks-which-meet-requested-voltage-on-dcn31.patch
queue-5.14/drm-amd-display-fix-prefetch-bandwidth-calculation-for-dcn3.1.patch
queue-5.14/drm-amd-display-fix-deadlock-when-falling-back-to-v2-from-v3.patch
