From 01a18aa309aec12461fb5e6aecb76f8b33810658 Mon Sep 17 00:00:00 2001
From: Ryan Lin <tsung-hua.lin@amd.com>
Date: Tue, 7 Feb 2023 23:03:48 +0800
Subject: [PATCH] drm/amd/display: Ext displays with dock can't recognized
after resume
[Why]
Needs to set the default value of the LTTPR timeout after resume.
[How]
Set the default (3.2ms) timeout at resuming if the sink supports
LTTPR
Reviewed-by: Jerry Zuo <Jerry.Zuo@amd.com>
Acked-by: Qingqing Zhuo <qingqing.zhuo@amd.com>
Signed-off-by: Ryan Lin <tsung-hua.lin@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
---
drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 10 ++++++++++
.../gpu/drm/amd/display/dc/link/protocols/link_ddc.h | 1 +
.../amd/display/dc/link/protocols/link_dp_capability.c | 2 --
3 files changed, 11 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 79ae01ac4b19e..009ef917dad47 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -41,6 +41,8 @@
#include "dpcd_defs.h"
#include "link/protocols/link_dpcd.h"
#include "link_service_types.h"
+#include "link/protocols/link_dp_capability.h"
+#include "link/protocols/link_ddc.h"
#include "vid.h"
#include "amdgpu.h"
@@ -2302,6 +2304,14 @@ static void s3_handle_mst(struct drm_device *dev, bool suspend)
if (suspend) {
drm_dp_mst_topology_mgr_suspend(mgr);
} else {
+ /* if extended timeout is supported in hardware,
+ * default to LTTPR timeout (3.2ms) first as a W/A for DP link layer
+ * CTS 4.2.1.1 regression introduced by CTS specs requirement update.
+ */
+ try_to_configure_aux_timeout(aconnector->dc_link->ddc, LINK_AUX_DEFAULT_LTTPR_TIMEOUT_PERIOD);
+ if (!dp_is_lttpr_present(aconnector->dc_link))
+ try_to_configure_aux_timeout(aconnector->dc_link->ddc, LINK_AUX_DEFAULT_TIMEOUT_PERIOD);
+
ret = drm_dp_mst_topology_mgr_resume(mgr, true);
if (ret < 0) {
dm_helpers_dp_mst_stop_top_mgr(aconnector->dc_link->ctx,
diff --git a/drivers/gpu/drm/amd/display/dc/link/protocols/link_ddc.h b/drivers/gpu/drm/amd/display/dc/link/protocols/link_ddc.h
index 86e9d2e886d6f..aaa5064408ba4 100644
--- a/drivers/gpu/drm/amd/display/dc/link/protocols/link_ddc.h
+++ b/drivers/gpu/drm/amd/display/dc/link/protocols/link_ddc.h
@@ -33,6 +33,7 @@
#define DPVGA_DONGLE_AUX_DEFER_WA_DELAY 40
#define I2C_OVER_AUX_DEFER_WA_DELAY_1MS 1
#define LINK_AUX_DEFAULT_LTTPR_TIMEOUT_PERIOD 3200 /*us*/
+#define LINK_AUX_DEFAULT_TIMEOUT_PERIOD 552 /*us*/
#define EDID_SEGMENT_SIZE 256
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 4874d1bf1dcb0..d4370856f164a 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
@@ -60,8 +60,6 @@
#define MIN(X, Y) ((X) < (Y) ? (X) : (Y))
#endif
-#define LINK_AUX_DEFAULT_TIMEOUT_PERIOD 552 /*us*/
-
struct dp_lt_fallback_entry {
enum dc_lane_count lane_count;
enum dc_link_rate link_rate;
--
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