From cadd18897c7786c2291a5368ca37f74ea3b66795 Mon Sep 17 00:00:00 2001
From: Zhikai Zhai <zhikai.zhai@amd.com>
Date: Fri, 30 Jun 2023 13:56:04 +0800
Subject: drm/amd/display: refine to decide the verified link setting
Git-commit: c99fcb02bc73d33f9cc52b1e9b705d7a3320c50b
Patch-mainline: v6.6-rc1
References: jsc#PED-3527 jsc#PED-5475 jsc#PED-6068 jsc#PED-6070 jsc#PED-6116 jsc#PED-6120 jsc#PED-5065 jsc#PED-5477 jsc#PED-5511 jsc#PED-6041 jsc#PED-6069 jsc#PED-6071
[WHY]
We return false by default when link training fail at link loss.
It will cause we get a fail verified link caps directly.
[HOW]
Record the highest verified link caps. Use the recorded value as
the verified link caps if it is not successful in the last attempt
to avoid to use the lowest link setting.
Reviewed-by: Wenjing Liu <wenjing.liu@amd.com>
Acked-by: Alan Liu <haoping.liu@amd.com>
Signed-off-by: Zhikai Zhai <zhikai.zhai@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
.../dc/link/protocols/link_dp_capability.c | 17 ++++++++++++-----
1 file changed, 12 insertions(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c
index 3a5e80b57711..03aae0c25022 100644
--- a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c
+++ b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c
@@ -2165,7 +2165,9 @@ static bool dp_verify_link_cap(
link,
&irq_data))
(*fail_count)++;
-
+ } else if (status == LINK_TRAINING_LINK_LOSS) {
+ success = true;
+ (*fail_count)++;
} else {
(*fail_count)++;
}
@@ -2188,6 +2190,7 @@ bool dp_verify_link_cap_with_retries(
int i = 0;
bool success = false;
int fail_count = 0;
+ struct dc_link_settings last_verified_link_cap = fail_safe_link_settings;
dp_trace_detect_lt_init(link);
@@ -2204,10 +2207,14 @@ bool dp_verify_link_cap_with_retries(
if (!link_detect_connection_type(link, &type) || type == dc_connection_none) {
link->verified_link_cap = fail_safe_link_settings;
break;
- } else if (dp_verify_link_cap(link, known_limit_link_setting,
- &fail_count) && fail_count == 0) {
- success = true;
- break;
+ } else if (dp_verify_link_cap(link, known_limit_link_setting, &fail_count)) {
+ last_verified_link_cap = link->verified_link_cap;
+ if (fail_count == 0) {
+ success = true;
+ break;
+ }
+ } else {
+ link->verified_link_cap = last_verified_link_cap;
}
fsleep(10 * 1000);
}
--
2.43.0