[Intel-gfx] [PATCH 4/7] drm/i915/display/psr: Handle plane restrictions at every page flip

[Gwan-gyeong Mun]

On 9/29/21 9:20 PM, Ville Syrjälä wrote:
> On Wed, Sep 29, 2021 at 08:50:12PM +0300, Gwan-gyeong Mun wrote:
>>
>>
>> On 9/23/21 10:46 PM, José Roberto de Souza wrote:
>>> PSR2 selective is not supported over rotated and scaled planes.
>>> We had the rotation check in intel_psr2_sel_fetch_config_valid()
>>> but that code path is only execute when a modeset is needed and
>>> change those plane parameters do not require a modeset.
>>>
>>> Also need to check those restricions in the second
>>> for_each_oldnew_intel_plane_in_state() loop because the state could
>>> only have a plane that is not affected by those restricitons but
>>> the damaged area intersect with planes that has those restrictions,
>>> so a full plane fetch is required.
>>>
>>> BSpec: 55229
>>> Cc: Gwan-gyeong Mun <gwan-gyeong.mun at intel.com>
>>> Signed-off-by: José Roberto de Souza <jose.souza at intel.com>
>>> ---
>>>    drivers/gpu/drm/i915/display/intel_psr.c | 45 ++++++++++++++----------
>>>    1 file changed, 26 insertions(+), 19 deletions(-)
>>>
>>> diff --git a/drivers/gpu/drm/i915/display/intel_psr.c b/drivers/gpu/drm/i915/display/intel_psr.c
>>> index 1cc4130dec7b1..356e0e96abf4e 100644
>>> --- a/drivers/gpu/drm/i915/display/intel_psr.c
>>> +++ b/drivers/gpu/drm/i915/display/intel_psr.c
>>> @@ -720,11 +720,7 @@ tgl_dc3co_exitline_compute_config(struct intel_dp *intel_dp,
>>>    static bool intel_psr2_sel_fetch_config_valid(struct intel_dp *intel_dp,
>>>    					      struct intel_crtc_state *crtc_state)
>>>    {
>>> -	struct intel_atomic_state *state = to_intel_atomic_state(crtc_state->uapi.state);
>>>    	struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
>>> -	struct intel_plane_state *plane_state;
>>> -	struct intel_plane *plane;
>>> -	int i;
>>>    
>>>    	if (!dev_priv->params.enable_psr2_sel_fetch &&
>>>    	    intel_dp->psr.debug != I915_PSR_DEBUG_ENABLE_SEL_FETCH) {
>>> @@ -739,14 +735,6 @@ static bool intel_psr2_sel_fetch_config_valid(struct intel_dp *intel_dp,
>>>    		return false;
>>>    	}
>>>    
>>> -	for_each_new_intel_plane_in_state(state, plane, plane_state, i) {
>>> -		if (plane_state->uapi.rotation != DRM_MODE_ROTATE_0) {
>>> -			drm_dbg_kms(&dev_priv->drm,
>>> -				    "PSR2 sel fetch not enabled, plane rotated\n");
>>> -			return false;
>>> -		}
>>> -	}
>>> -
>>>    	/* Wa_14010254185 Wa_14010103792 */
>>>    	if (IS_TGL_DISPLAY_STEP(dev_priv, STEP_A0, STEP_C0)) {
>>>    		drm_dbg_kms(&dev_priv->drm,
>>> @@ -1586,6 +1574,26 @@ static void cursor_area_workaround(const struct intel_plane_state *new_plane_sta
>>>    	clip_area_update(pipe_clip, damaged_area);
>>>    }
>>>    
>>> +/*
>>> + * TODO: Not clear how to handle planes with negative position,
>>> + * also planes are not updated if they have a negative X
>>> + * position so for now doing a full update in this cases
>>> + *
>>> + * Plane scaling and rotation is not supported by selective fetch and both
>>> + * properties can change without a modeset, so need to be check at every
>>> + * atomic commmit.
>>> + */
>>> +static bool psr2_sel_fetch_plane_state_supported(const struct intel_plane_state *plane_state)
>>> +{
>>> +	if (plane_state->uapi.dst.y1 < 0 ||
>>> +	    plane_state->uapi.dst.x1 < 0 ||
>> intel_atomic_plane_check_clipping() function makes
>> plane_state->uapi.dst.x1 and plane_state->uapi.dst.y1 non-negative
>> values, so there is no need to deal with negative positions here.
> 
> Cursor can have negative coordinates as it's hardware that will do the
> clipping for us.
> 
Yes, you are right, thanks for pointing out it. The cursor plane's 
CUR_POS register has X and Y Position Sign bits.

Reviewed-by: Gwan-gyeong Mun <gwan-gyeong.mun at intel.com>
>>
>> And the rest of the changes look good to me.
>>> +	    plane_state->scaler_id >= 0 ||
>>> +	    plane_state->uapi.rotation != DRM_MODE_ROTATE_0)
>>> +		return false;
>>> +
>>> +	return true;
>>> +}
>>> +
>>>    int intel_psr2_sel_fetch_update(struct intel_atomic_state *state,
>>>    				struct intel_crtc *crtc)
>>>    {
>>> @@ -1618,13 +1626,7 @@ int intel_psr2_sel_fetch_update(struct intel_atomic_state *state,
>>>    		    !old_plane_state->uapi.visible)
>>>    			continue;
>>>    
>>> -		/*
>>> -		 * TODO: Not clear how to handle planes with negative position,
>>> -		 * also planes are not updated if they have a negative X
>>> -		 * position so for now doing a full update in this cases
>>> -		 */
>>> -		if (new_plane_state->uapi.dst.y1 < 0 ||
>>> -		    new_plane_state->uapi.dst.x1 < 0) {
>>> +		if (!psr2_sel_fetch_plane_state_supported(new_plane_state)) {
>>>    			full_update = true;
>>>    			break;
>>>    		}
>>> @@ -1703,6 +1705,11 @@ int intel_psr2_sel_fetch_update(struct intel_atomic_state *state,
>>>    		if (!drm_rect_intersect(&inter, &new_plane_state->uapi.dst))
>>>    			continue;
>>>    
>>> +		if (!psr2_sel_fetch_plane_state_supported(new_plane_state)) {
>>> +			full_update = true;
>>> +			break;
>>> +		}
>>> +
>>>    		sel_fetch_area = &new_plane_state->psr2_sel_fetch_area;
>>>    		sel_fetch_area->y1 = inter.y1 - new_plane_state->uapi.dst.y1;
>>>    		sel_fetch_area->y2 = inter.y2 - new_plane_state->uapi.dst.y1;
>>>
>