From: Alvin Lee <[email protected]> [Description] - Due to bandwidth / arbitration issues at 200Mhz DCFCLK, we want to enforce minimum 60us of prefetch to avoid intermittent underflow issues - Since 60us prefetch is already enforced for UCLK DPM0, and many DCFCLK's > 200Mhz are mapped to UCLK DPM1, in theory there should not be any UCLK DPM regressions by enforcing greater prefetch
Reviewed-by: Nevenko Stupar <[email protected]> Reviewed-by: Jun Lei <[email protected]> Cc: Mario Limonciello <[email protected]> Cc: Alex Deucher <[email protected]> Cc: [email protected] Acked-by: Alex Hung <[email protected]> Signed-off-by: Alvin Lee <[email protected]> --- .../gpu/drm/amd/display/dc/dml/dcn32/display_mode_vba_32.c | 5 +++-- .../gpu/drm/amd/display/dc/dml/dcn32/display_mode_vba_32.h | 1 + 2 files changed, 4 insertions(+), 2 deletions(-) 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 66f44a013fe5..958d27224f64 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 @@ -810,7 +810,8 @@ static void DISPCLKDPPCLKDCFCLKDeepSleepPrefetchParametersWatermarksAndPerforman v->SwathHeightY[k], v->SwathHeightC[k], TWait, - v->DRAMSpeedPerState[mode_lib->vba.VoltageLevel] <= MEM_STROBE_FREQ_MHZ ? + (v->DRAMSpeedPerState[mode_lib->vba.VoltageLevel] <= MEM_STROBE_FREQ_MHZ || + v->DCFCLKPerState[mode_lib->vba.VoltageLevel] <= MIN_DCFCLK_FREQ_MHZ) ? mode_lib->vba.ip.min_prefetch_in_strobe_us : 0, /* Output */ &v->DSTXAfterScaler[k], @@ -3314,7 +3315,7 @@ 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->DRAMSpeedPerState[i] <= MEM_STROBE_FREQ_MHZ || v->DCFCLKState[i][j] <= MIN_DCFCLK_FREQ_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 500b3dd6052d..d98e36a9a09c 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 @@ -53,6 +53,7 @@ #define BPP_BLENDED_PIPE 0xffffffff #define MEM_STROBE_FREQ_MHZ 1600 +#define MIN_DCFCLK_FREQ_MHZ 200 #define MEM_STROBE_MAX_DELIVERY_TIME_US 60.0 struct display_mode_lib; -- 2.40.0
