[PATCH 6.19 791/844] drm/amd/display: Increase DCN35 SR enter/exit latency
From: Sasha Levin
Date: Sat Feb 28 2026 - 14:52:26 EST
From: Leo Li <sunpeng.li@xxxxxxx>
[ Upstream commit 318917e1d8ecc89f820f4fabf79935f4fed718cd ]
[Why & How]
On Framework laptops with DDR5 modules, underflow can be observed.
It's unclear why it only occurs on specific desktop contents. However,
increasing enter/exit latencies by 3us seems to resolve it.
Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/4463
Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas@xxxxxxx>
Signed-off-by: Leo Li <sunpeng.li@xxxxxxx>
Signed-off-by: Tom Chung <chiahsuan.chung@xxxxxxx>
Tested-by: Daniel Wheeler <daniel.wheeler@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
.../amd/display/dc/clk_mgr/dcn35/dcn35_clk_mgr.c | 16 ++++++++--------
.../gpu/drm/amd/display/dc/dml/dcn35/dcn35_fpu.c | 4 ++--
2 files changed, 10 insertions(+), 10 deletions(-)
diff --git a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn35/dcn35_clk_mgr.c b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn35/dcn35_clk_mgr.c
index dfd0c9505af09..0a21910c87e10 100644
--- a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn35/dcn35_clk_mgr.c
+++ b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn35/dcn35_clk_mgr.c
@@ -768,32 +768,32 @@ static struct wm_table ddr5_wm_table = {
.wm_inst = WM_A,
.wm_type = WM_TYPE_PSTATE_CHG,
.pstate_latency_us = 11.72,
- .sr_exit_time_us = 28.0,
- .sr_enter_plus_exit_time_us = 30.0,
+ .sr_exit_time_us = 31.0,
+ .sr_enter_plus_exit_time_us = 33.0,
.valid = true,
},
{
.wm_inst = WM_B,
.wm_type = WM_TYPE_PSTATE_CHG,
.pstate_latency_us = 11.72,
- .sr_exit_time_us = 28.0,
- .sr_enter_plus_exit_time_us = 30.0,
+ .sr_exit_time_us = 31.0,
+ .sr_enter_plus_exit_time_us = 33.0,
.valid = true,
},
{
.wm_inst = WM_C,
.wm_type = WM_TYPE_PSTATE_CHG,
.pstate_latency_us = 11.72,
- .sr_exit_time_us = 28.0,
- .sr_enter_plus_exit_time_us = 30.0,
+ .sr_exit_time_us = 31.0,
+ .sr_enter_plus_exit_time_us = 33.0,
.valid = true,
},
{
.wm_inst = WM_D,
.wm_type = WM_TYPE_PSTATE_CHG,
.pstate_latency_us = 11.72,
- .sr_exit_time_us = 28.0,
- .sr_enter_plus_exit_time_us = 30.0,
+ .sr_exit_time_us = 31.0,
+ .sr_enter_plus_exit_time_us = 33.0,
.valid = true,
},
}
diff --git a/drivers/gpu/drm/amd/display/dc/dml/dcn35/dcn35_fpu.c b/drivers/gpu/drm/amd/display/dc/dml/dcn35/dcn35_fpu.c
index 817a370e80a77..8a177d5ae213e 100644
--- a/drivers/gpu/drm/amd/display/dc/dml/dcn35/dcn35_fpu.c
+++ b/drivers/gpu/drm/amd/display/dc/dml/dcn35/dcn35_fpu.c
@@ -164,8 +164,8 @@ struct _vcs_dpi_soc_bounding_box_st dcn3_5_soc = {
},
},
.num_states = 5,
- .sr_exit_time_us = 28.0,
- .sr_enter_plus_exit_time_us = 30.0,
+ .sr_exit_time_us = 31.0,
+ .sr_enter_plus_exit_time_us = 33.0,
.sr_exit_z8_time_us = 250.0,
.sr_enter_plus_exit_z8_time_us = 350.0,
.fclk_change_latency_us = 24.0,
--
2.51.0