[PATCH] drm/amd/display: Add below the range support for FreeSync

Nicholas Kazlauskas nkazlaus at amd.com
Wed Dec 5 15:04:41 UTC 2018


On 2018-12-05 9:30 a.m., Li, Sun peng (Leo) wrote:
> 
> 
> On 2018-12-05 8:40 a.m., Nicholas Kazlauskas wrote:
>> [Why]
>> When application flip-rate is below the minimum vrr refresh rate.
>>
>> Variable refresh rate monitors extend the front porch duration until
>> flip or timeout occurs. For cases where the application flip-rate is
> 
> Did something get cut off here? With that fixed,
> Acked-by: Leo Li <sunpeng.li at amd.com>

Those top two paragraphs were supposed to be cut, I think I formatted 
the wrong patch for that.

The code itself is the correct version, however. Thanks.

Nicholas Kazlauskas

> 
>>
>> When the flip-rate is below the minimum supported variable refresh rate
>> range for the monitor the front porch wait will timeout and be
>> frequently misaligned resulting in stuttering and/or flickering.
>>
>> The FreeSync module can still maintain a smooth and flicker free
>> image when the monitor has a refresh rate range such that the maximum
>> refresh > 2 * minimum refresh by utilizing low framerate compensation,
>> "below the range".
>>
>> [How]
>> Hook up the pre-flip and post-flip handlers from the FreeSync module.
>> These adjust the minimum/maximum vrr range to duplicate frames
>> when appropriate by tracking flip timestamps.
>>
>> Cc: Leo Li <sunpeng.li at amd.com>
>> Cc: Harry Wentland <harry.wentland at amd.com>
>> Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas at amd.com>
>> ---
>>    .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 79 ++++++++++++++-----
>>    .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h |  2 +-
>>    2 files changed, 62 insertions(+), 19 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
>> index 23d61570df17..e2de064426fc 100644
>> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
>> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
>> @@ -328,12 +328,29 @@ static void dm_crtc_high_irq(void *interrupt_params)
>>    	struct common_irq_params *irq_params = interrupt_params;
>>    	struct amdgpu_device *adev = irq_params->adev;
>>    	struct amdgpu_crtc *acrtc;
>> +	struct dm_crtc_state *acrtc_state;
>>    
>>    	acrtc = get_crtc_by_otg_inst(adev, irq_params->irq_src - IRQ_TYPE_VBLANK);
>>    
>>    	if (acrtc) {
>>    		drm_crtc_handle_vblank(&acrtc->base);
>>    		amdgpu_dm_crtc_handle_crc_irq(&acrtc->base);
>> +
>> +		acrtc_state = to_dm_crtc_state(acrtc->base.state);
>> +
>> +		if (acrtc_state->stream &&
>> +		    acrtc_state->vrr_params.supported &&
>> +		    acrtc_state->freesync_config.state == VRR_STATE_ACTIVE_VARIABLE) {
>> +			mod_freesync_handle_v_update(
>> +				adev->dm.freesync_module,
>> +				acrtc_state->stream,
>> +				&acrtc_state->vrr_params);
>> +
>> +			dc_stream_adjust_vmin_vmax(
>> +				adev->dm.dc,
>> +				acrtc_state->stream,
>> +				&acrtc_state->vrr_params.adjust);
>> +		}
>>    	}
>>    }
>>    
>> @@ -3001,7 +3018,7 @@ dm_crtc_duplicate_state(struct drm_crtc *crtc)
>>    		dc_stream_retain(state->stream);
>>    	}
>>    
>> -	state->adjust = cur->adjust;
>> +	state->vrr_params = cur->vrr_params;
>>    	state->vrr_infopacket = cur->vrr_infopacket;
>>    	state->abm_level = cur->abm_level;
>>    	state->vrr_supported = cur->vrr_supported;
>> @@ -4396,9 +4413,11 @@ struct dc_stream_status *dc_state_get_stream_status(
>>    static void update_freesync_state_on_stream(
>>    	struct amdgpu_display_manager *dm,
>>    	struct dm_crtc_state *new_crtc_state,
>> -	struct dc_stream_state *new_stream)
>> +	struct dc_stream_state *new_stream,
>> +	struct dc_plane_state *surface,
>> +	u32 flip_timestamp_in_us)
>>    {
>> -	struct mod_vrr_params vrr = {0};
>> +	struct mod_vrr_params vrr_params = new_crtc_state->vrr_params;
>>    	struct dc_info_packet vrr_infopacket = {0};
>>    	struct mod_freesync_config config = new_crtc_state->freesync_config;
>>    
>> @@ -4425,43 +4444,52 @@ static void update_freesync_state_on_stream(
>>    
>>    	mod_freesync_build_vrr_params(dm->freesync_module,
>>    				      new_stream,
>> -				      &config, &vrr);
>> +				      &config, &vrr_params);
>> +
>> +	if (surface) {
>> +		mod_freesync_handle_preflip(
>> +			dm->freesync_module,
>> +			surface,
>> +			new_stream,
>> +			flip_timestamp_in_us,
>> +			&vrr_params);
>> +	}
>>    
>>    	mod_freesync_build_vrr_infopacket(
>>    		dm->freesync_module,
>>    		new_stream,
>> -		&vrr,
>> +		&vrr_params,
>>    		PACKET_TYPE_VRR,
>>    		TRANSFER_FUNC_UNKNOWN,
>>    		&vrr_infopacket);
>>    
>>    	new_crtc_state->freesync_timing_changed =
>> -		(memcmp(&new_crtc_state->adjust,
>> -			&vrr.adjust,
>> -			sizeof(vrr.adjust)) != 0);
>> +		(memcmp(&new_crtc_state->vrr_params.adjust,
>> +			&vrr_params.adjust,
>> +			sizeof(vrr_params.adjust)) != 0);
>>    
>>    	new_crtc_state->freesync_vrr_info_changed =
>>    		(memcmp(&new_crtc_state->vrr_infopacket,
>>    			&vrr_infopacket,
>>    			sizeof(vrr_infopacket)) != 0);
>>    
>> -	new_crtc_state->adjust = vrr.adjust;
>> +	new_crtc_state->vrr_params = vrr_params;
>>    	new_crtc_state->vrr_infopacket = vrr_infopacket;
>>    
>> -	new_stream->adjust = new_crtc_state->adjust;
>> +	new_stream->adjust = new_crtc_state->vrr_params.adjust;
>>    	new_stream->vrr_infopacket = vrr_infopacket;
>>    
>>    	if (new_crtc_state->freesync_vrr_info_changed)
>>    		DRM_DEBUG_KMS("VRR packet update: crtc=%u enabled=%d state=%d",
>>    			      new_crtc_state->base.crtc->base.id,
>>    			      (int)new_crtc_state->base.vrr_enabled,
>> -			      (int)vrr.state);
>> +			      (int)vrr_params.state);
>>    
>>    	if (new_crtc_state->freesync_timing_changed)
>>    		DRM_DEBUG_KMS("VRR timing update: crtc=%u min=%u max=%u\n",
>>    			      new_crtc_state->base.crtc->base.id,
>> -			      vrr.adjust.v_total_min,
>> -			      vrr.adjust.v_total_max);
>> +				  vrr_params.adjust.v_total_min,
>> +				  vrr_params.adjust.v_total_max);
>>    }
>>    
>>    /*
>> @@ -4488,6 +4516,7 @@ static void amdgpu_dm_do_flip(struct drm_crtc *crtc,
>>    	struct dc_stream_update stream_update = {0};
>>    	struct dm_crtc_state *acrtc_state = to_dm_crtc_state(crtc->state);
>>    	struct dc_stream_status *stream_status;
>> +	struct dc_plane_state *surface;
>>    
>>    
>>    	/* Prepare wait for target vblank early - before the fence-waits */
>> @@ -4536,6 +4565,7 @@ static void amdgpu_dm_do_flip(struct drm_crtc *crtc,
>>    	addr.address.grph.addr.low_part = lower_32_bits(afb->address);
>>    	addr.address.grph.addr.high_part = upper_32_bits(afb->address);
>>    	addr.flip_immediate = async_flip;
>> +	addr.flip_timestamp_in_us = ktime_get_ns() / 1000;
>>    
>>    
>>    	if (acrtc->base.state->event)
>> @@ -4550,8 +4580,10 @@ static void amdgpu_dm_do_flip(struct drm_crtc *crtc,
>>    		return;
>>    	}
>>    
>> -	surface_updates->surface = stream_status->plane_states[0];
>> -	if (!surface_updates->surface) {
>> +	surface = stream_status->plane_states[0];
>> +	surface_updates->surface = surface;
>> +
>> +	if (!surface) {
>>    		DRM_ERROR("No surface for CRTC: id=%d\n",
>>    			acrtc->crtc_id);
>>    		return;
>> @@ -4562,7 +4594,9 @@ static void amdgpu_dm_do_flip(struct drm_crtc *crtc,
>>    		update_freesync_state_on_stream(
>>    			&adev->dm,
>>    			acrtc_state,
>> -			acrtc_state->stream);
>> +			acrtc_state->stream,
>> +			surface,
>> +			addr.flip_timestamp_in_us);
>>    
>>    		if (acrtc_state->freesync_timing_changed)
>>    			stream_update.adjust =
>> @@ -4573,6 +4607,14 @@ static void amdgpu_dm_do_flip(struct drm_crtc *crtc,
>>    				&acrtc_state->stream->vrr_infopacket;
>>    	}
>>    
>> +	/* Update surface timing information. */
>> +	surface->time.time_elapsed_in_us[surface->time.index] =
>> +		addr.flip_timestamp_in_us - surface->time.prev_update_time_in_us;
>> +	surface->time.prev_update_time_in_us = addr.flip_timestamp_in_us;
>> +	surface->time.index++;
>> +	if (surface->time.index >= DC_PLANE_UPDATE_TIMES_MAX)
>> +		surface->time.index = 0;
>> +
>>    	dc_commit_updates_for_stream(adev->dm.dc,
>>    					     surface_updates,
>>    					     1,
>> @@ -5256,6 +5298,7 @@ static void get_freesync_config_for_crtc(
>>    		config.max_refresh_in_uhz =
>>    				aconnector->max_vfreq * 1000000;
>>    		config.vsif_supported = true;
>> +		config.btr = true;
>>    	}
>>    
>>    	new_crtc_state->freesync_config = config;
>> @@ -5266,8 +5309,8 @@ static void reset_freesync_config_for_crtc(
>>    {
>>    	new_crtc_state->vrr_supported = false;
>>    
>> -	memset(&new_crtc_state->adjust, 0,
>> -	       sizeof(new_crtc_state->adjust));
>> +	memset(&new_crtc_state->vrr_params, 0,
>> +	       sizeof(new_crtc_state->vrr_params));
>>    	memset(&new_crtc_state->vrr_infopacket, 0,
>>    	       sizeof(new_crtc_state->vrr_infopacket));
>>    }
>> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h
>> index 4326dc256491..59d20781dfdb 100644
>> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h
>> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h
>> @@ -260,7 +260,7 @@ struct dm_crtc_state {
>>    
>>    	bool vrr_supported;
>>    	struct mod_freesync_config freesync_config;
>> -	struct dc_crtc_timing_adjust adjust;
>> +	struct mod_vrr_params vrr_params;
>>    	struct dc_info_packet vrr_infopacket;
>>    
>>    	int abm_level;
>>



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