[PATCH] drm/amd/pm: Enable gfx DCS feature

[Kenneth Feng]

Background:
Gfx Duty Cycle Scaling(DCS) is applied on the small power limit skus.
When the current/power/temperature exceeds the limit with the heavy workload,
the gfx core can be shut off and powered on back and forth.
The ON time and OFF time is determined by the firmware according to
the accumulated power credits.
This feature is different from gfxoff.Gfxoff is applied in the idle case
and DCS is applied in the case with heavey workload.There are two types of DCS:
Async DCS and Frame-aligned DCS.Frame-aligned DCS is applied on 3D fullscreen
and VR workload.
Since we only supports Async DCS now,disalbe DCS when the 3D fullscreen or
the VR workload type is chosen.

Verification:
The power is lowerer or the perf/watt is increased in the throttling case.
To be simplified, the entry/exit counter can be observed from the firmware.

Signed-off-by: Kenneth Feng <kenneth.feng at amd.com>
---
 .../gpu/drm/amd/pm/swsmu/smu11/sienna_cichlid_ppt.c  | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/drivers/gpu/drm/amd/pm/swsmu/smu11/sienna_cichlid_ppt.c b/drivers/gpu/drm/amd/pm/swsmu/smu11/sienna_cichlid_ppt.c
index 24f3c96a5e5e..436d94cbb166 100644
--- a/drivers/gpu/drm/amd/pm/swsmu/smu11/sienna_cichlid_ppt.c
+++ b/drivers/gpu/drm/amd/pm/swsmu/smu11/sienna_cichlid_ppt.c
@@ -261,6 +261,9 @@ sienna_cichlid_get_allowed_feature_mask(struct smu_context *smu,
 		*(uint64_t *)feature_mask |= FEATURE_MASK(FEATURE_DPM_GFX_GPO_BIT);
 	}
 
+	if (adev->asic_type == CHIP_NAVY_FLOUNDER || adev->asic_type == CHIP_DIMGREY_CAVEFISH)
+		*(uint64_t *)feature_mask |= FEATURE_MASK(FEATURE_GFX_DCS_BIT);
+
 	if (adev->pm.pp_feature & PP_MCLK_DPM_MASK)
 		*(uint64_t *)feature_mask |= FEATURE_MASK(FEATURE_DPM_UCLK_BIT)
 					| FEATURE_MASK(FEATURE_MEM_VDDCI_SCALING_BIT)
@@ -1437,6 +1440,15 @@ static int sienna_cichlid_set_power_profile_mode(struct smu_context *smu, long *
 	smu_cmn_send_smc_msg_with_param(smu, SMU_MSG_SetWorkloadMask,
 				    1 << workload_type, NULL);
 
+	/* have to disable dcs if it's the 3D fullscreen or VR workload type */
+	if (smu->adev->asic_type == CHIP_NAVY_FLOUNDER ||
+		smu->adev->asic_type == CHIP_DIMGREY_CAVEFISH) {
+		ret = smu_cmn_feature_set_enabled(smu, SMU_FEATURE_GFX_DCS_BIT, (workload_type ==
+			WORKLOAD_PPLIB_FULL_SCREEN_3D_BIT || workload_type == WORKLOAD_PPLIB_VR_BIT) ? 0 : 1);
+		if (ret)
+			return ret;
+	}
+
 	return ret;
 }
 
-- 
2.17.1