From: Ryan Seto <ryanseto@xxxxxxx> [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.varone@xxxxxxx> Signed-off-by: Ryan Seto <ryanseto@xxxxxxx> Signed-off-by: Tom Chung <chiahsuan.chung@xxxxxxx> --- .../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 4c33d99ca7e8..4c504cb0e1c5 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) { @@ -3737,6 +3738,7 @@ 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; } -- 2.34.1