From: Ryan Seto <ryans...@amd.com>
[ Upstream commit 29c1c20496a7a9bafe2bc2f833d69aa52e0f2c2d ]
[Why]
For some VR headsets with large blanks, it's possible
to overflow the OTG_VSTARTUP_PARAM:VSTARTUP_START
register. This can lead to incorrect DML calculations
and underflow downstream.
[How]
Min the calcualted max_vstartup_lines with the max
value of the register.
Reviewed-by: Dillon Varone <dillon.var...@amd.com>
Signed-off-by: Ryan Seto <ryans...@amd.com>
Signed-off-by: Tom Chung <chiahsuan.ch...@amd.com>
Tested-by: Daniel Wheeler <daniel.whee...@amd.com>
Signed-off-by: Alex Deucher <alexander.deuc...@amd.com>
Signed-off-by: Sasha Levin <sas...@kernel.org>
---
.../display/dc/dml2/dml21/src/dml2_core/dml2_core_dcn4_calcs.c | 2 ++
1 file changed, 2 insertions(+)
diff --git
a/drivers/gpu/drm/amd/display/dc/dml2/dml21/src/dml2_core/dml2_core_dcn4_calcs.c
b/drivers/gpu/drm/amd/display/dc/dml2/dml21/src/dml2_core/dml2_core_dcn4_calcs.c
index 8ed49a9df3780..c1ff869512f27 100644
---
a/drivers/gpu/drm/amd/display/dc/dml2/dml21/src/dml2_core/dml2_core_dcn4_calcs.c
+++
b/drivers/gpu/drm/amd/display/dc/dml2/dml21/src/dml2_core/dml2_core_dcn4_calcs.c
@@ -15,6 +15,7 @@
//#define DML_MODE_SUPPORT_USE_DPM_DRAM_BW
//#define DML_GLOBAL_PREFETCH_CHECK
#define ALLOW_SDPIF_RATE_LIMIT_PRE_CSTATE
+#define DML_MAX_VSTARTUP_START 1023
const char *dml2_core_internal_bw_type_str(enum dml2_core_internal_bw_type
bw_type)
{
@@ -3726,6 +3727,7 @@ static unsigned int CalculateMaxVStartup(
dml2_printf("DML::%s: vblank_avail = %u\n", __func__, vblank_avail);
dml2_printf("DML::%s: max_vstartup_lines = %u\n", __func__,
max_vstartup_lines);
#endif
+ max_vstartup_lines = (unsigned int)math_min2(max_vstartup_lines,
DML_MAX_VSTARTUP_START);
return max_vstartup_lines;
}
--
2.39.5
