This is a note to let you know that I've just added the patch titled
drm/amd/display: Apply 60us prefetch for DCFCLK <= 300Mhz
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-apply-60us-prefetch-for-dcfclk-300mh.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.
commit c445bc727d07ca4886db80897bbaba2d339e4b57
Author: Alvin Lee <alvin.lee2@xxxxxxx>
Date: Thu May 11 15:25:01 2023 -0400
drm/amd/display: Apply 60us prefetch for DCFCLK <= 300Mhz
[ Upstream commit 7e60ab4eb3e4ba2adac46d737fdbbc5732bebd58 ]
[Description]
- Previously we wanted to apply extra 60us of prefetch for min DCFCLK
(200Mhz), but DCFCLK can be calculated to be 201Mhz which underflows
also without the extra prefetch
- Instead, apply the the extra 60us prefetch for any DCFCLK freq <=
300Mhz
Reviewed-by: Nevenko Stupar <nevenko.stupar@xxxxxxx>
Reviewed-by: Jun Lei <jun.lei@xxxxxxx>
Acked-by: Tom Chung <chiahsuan.chung@xxxxxxx>
Signed-off-by: Alvin Lee <alvin.lee2@xxxxxxx>
Tested-by: Daniel Wheeler <daniel.wheeler@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/gpu/drm/amd/display/dc/dml/dcn32/display_mode_vba_32.c b/drivers/gpu/drm/amd/display/dc/dml/dcn32/display_mode_vba_32.c
index d75248b6cae99..9a5150e96017a 100644
--- a/drivers/gpu/drm/amd/display/dc/dml/dcn32/display_mode_vba_32.c
+++ b/drivers/gpu/drm/amd/display/dc/dml/dcn32/display_mode_vba_32.c
@@ -811,7 +811,7 @@ static void DISPCLKDPPCLKDCFCLKDeepSleepPrefetchParametersWatermarksAndPerforman
v->SwathHeightC[k],
TWait,
(v->DRAMSpeedPerState[mode_lib->vba.VoltageLevel] <= MEM_STROBE_FREQ_MHZ ||
- v->DCFCLKPerState[mode_lib->vba.VoltageLevel] <= MIN_DCFCLK_FREQ_MHZ) ?
+ v->DCFCLKPerState[mode_lib->vba.VoltageLevel] <= DCFCLK_FREQ_EXTRA_PREFETCH_REQ_MHZ) ?
mode_lib->vba.ip.min_prefetch_in_strobe_us : 0,
/* Output */
&v->DSTXAfterScaler[k],
@@ -3311,7 +3311,7 @@ void dml32_ModeSupportAndSystemConfigurationFull(struct display_mode_lib *mode_l
v->swath_width_chroma_ub_this_state[k],
v->SwathHeightYThisState[k],
v->SwathHeightCThisState[k], v->TWait,
- (v->DRAMSpeedPerState[i] <= MEM_STROBE_FREQ_MHZ || v->DCFCLKState[i][j] <= MIN_DCFCLK_FREQ_MHZ) ?
+ (v->DRAMSpeedPerState[i] <= MEM_STROBE_FREQ_MHZ || v->DCFCLKState[i][j] <= DCFCLK_FREQ_EXTRA_PREFETCH_REQ_MHZ) ?
mode_lib->vba.ip.min_prefetch_in_strobe_us : 0,
/* Output */
diff --git a/drivers/gpu/drm/amd/display/dc/dml/dcn32/display_mode_vba_32.h b/drivers/gpu/drm/amd/display/dc/dml/dcn32/display_mode_vba_32.h
index d98e36a9a09cc..c4745d63039bb 100644
--- a/drivers/gpu/drm/amd/display/dc/dml/dcn32/display_mode_vba_32.h
+++ b/drivers/gpu/drm/amd/display/dc/dml/dcn32/display_mode_vba_32.h
@@ -53,7 +53,7 @@
#define BPP_BLENDED_PIPE 0xffffffff
#define MEM_STROBE_FREQ_MHZ 1600
-#define MIN_DCFCLK_FREQ_MHZ 200
+#define DCFCLK_FREQ_EXTRA_PREFETCH_REQ_MHZ 300
#define MEM_STROBE_MAX_DELIVERY_TIME_US 60.0
struct display_mode_lib;
