[Intel-gfx] [PATCH 4/8] drm/i915: DRRS calls based on frontbuffer

[Daniel Vetter]

On Thu, Dec 11, 2014 at 02:22:53AM +0530, Vandana Kannan wrote:
> Calls have been added to invalidate/flush DRRS whenever invalidate/flush is
> called as part of frontbuffer tracking.
> Apart from calls as a result of GEM tracking to fb invalidate/flush, a
> call has been added to invalidate fb obj from crtc_page_flip as well. This
> is to track busyness through flip calls.

That shouldn't be required really. Or maybe I misunderstand what you mean
here ...

> The call to fb_obj_invalidate (in flip) is placed before queuing flip for this
> obj.
> 
> drrs_invalidate() and drrs_flush() check for drrs.dp which would be NULL if
> it was setup in drrs_enable(). This covers for the condition when DRRS is
> not supported.
> 
> Signed-off-by: Vandana Kannan <vandana.kannan at intel.com>
> ---
>  drivers/gpu/drm/i915/intel_display.c     |  8 +++--
>  drivers/gpu/drm/i915/intel_dp.c          | 51 ++++++++++++++++++++++++++++++++
>  drivers/gpu/drm/i915/intel_drv.h         |  3 ++
>  drivers/gpu/drm/i915/intel_frontbuffer.c |  2 ++
>  4 files changed, 61 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index a9bdc12..a4a565c 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -9717,6 +9717,11 @@ static int intel_crtc_page_flip(struct drm_crtc *crtc,
>  	if (ret)
>  		goto cleanup_pending;
>  
> +	i915_gem_track_fb(work->old_fb_obj, obj,
> +			  INTEL_FRONTBUFFER_PRIMARY(pipe));
> +
> +	intel_fb_obj_invalidate(obj, ring);
> +
>  	work->gtt_offset =
>  		i915_gem_obj_ggtt_offset(obj) + intel_crtc->dspaddr_offset;
>  
> @@ -9741,9 +9746,6 @@ static int intel_crtc_page_flip(struct drm_crtc *crtc,
>  	work->flip_queued_vblank = drm_vblank_count(dev, intel_crtc->pipe);
>  	work->enable_stall_check = true;
>  
> -	i915_gem_track_fb(work->old_fb_obj, obj,
> -			  INTEL_FRONTBUFFER_PRIMARY(pipe));
> -
>  	intel_disable_fbc(dev);
>  	intel_frontbuffer_flip_prepare(dev, INTEL_FRONTBUFFER_PRIMARY(pipe));
>  	mutex_unlock(&dev->struct_mutex);

This hunk here looks spurious. Or is it relate to what you mention in the
commit message? Please explain more in-depth.

> diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
> index 7098470..bc17900 100644
> --- a/drivers/gpu/drm/i915/intel_dp.c
> +++ b/drivers/gpu/drm/i915/intel_dp.c
> @@ -4902,6 +4902,57 @@ unlock:
>  	mutex_unlock(&dev_priv->drrs.mutex);
>  }
>  
> +void intel_edp_drrs_invalidate(struct drm_device *dev,
> +		unsigned frontbuffer_bits)
> +{
> +	struct drm_i915_private *dev_priv = dev->dev_private;
> +	struct drm_crtc *crtc;
> +	enum pipe pipe;
> +
> +	if (!dev_priv->drrs.dp)
> +		return;
> +
> +	mutex_lock(&dev_priv->drrs.mutex);
> +	crtc = dp_to_dig_port(dev_priv->drrs.dp)->base.base.crtc;
> +	pipe = to_intel_crtc(crtc)->pipe;
> +
> +	if (dev_priv->drrs.refresh_rate_type == DRRS_LOW_RR) {
> +		cancel_delayed_work_sync(&dev_priv->drrs.work);
> +		intel_dp_set_drrs_state(dev_priv->dev,
> +				dev_priv->drrs.dp->attached_connector->panel.
> +				fixed_mode->vrefresh);
> +	}
> +
> +	frontbuffer_bits &= INTEL_FRONTBUFFER_ALL_MASK(pipe);
> +
> +	dev_priv->drrs.busy_frontbuffer_bits |= frontbuffer_bits;
> +	mutex_unlock(&dev_priv->drrs.mutex);
> +}
> +
> +void intel_edp_drrs_flush(struct drm_device *dev,
> +		unsigned frontbuffer_bits)
> +{
> +	struct drm_i915_private *dev_priv = dev->dev_private;
> +	struct drm_crtc *crtc;
> +	enum pipe pipe;
> +
> +	if (!dev_priv->drrs.dp)
> +		return;
> +
> +	mutex_lock(&dev_priv->drrs.mutex);
> +	crtc = dp_to_dig_port(dev_priv->drrs.dp)->base.base.crtc;
> +	pipe = to_intel_crtc(crtc)->pipe;
> +	dev_priv->drrs.busy_frontbuffer_bits &= ~frontbuffer_bits;
> +
> +	cancel_delayed_work_sync(&dev_priv->drrs.work);
> +
> +	if (dev_priv->drrs.refresh_rate_type != DRRS_LOW_RR &&
> +			!dev_priv->drrs.busy_frontbuffer_bits)
> +		schedule_delayed_work(&dev_priv->drrs.work,
> +				msecs_to_jiffies(1000));

With mod_delayed_work you can avoid the cancel_work. Also sync will
probably deadlock.
-Daniel

> +	mutex_unlock(&dev_priv->drrs.mutex);
> +}
> +
>  static struct drm_display_mode *
>  intel_dp_drrs_init(struct intel_connector *intel_connector,
>  		struct drm_display_mode *fixed_mode)
> diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
> index 1c3c25a..763c097 100644
> --- a/drivers/gpu/drm/i915/intel_drv.h
> +++ b/drivers/gpu/drm/i915/intel_drv.h
> @@ -1004,6 +1004,9 @@ int intel_update_plane(struct drm_plane *plane, struct drm_crtc *crtc,
>  int intel_disable_plane(struct drm_plane *plane);
>  void intel_edp_drrs_enable(struct intel_dp *intel_dp);
>  void intel_edp_drrs_disable(struct intel_dp *intel_dp);
> +void intel_edp_drrs_invalidate(struct drm_device *dev,
> +		unsigned frontbuffer_bits);
> +void intel_edp_drrs_flush(struct drm_device *dev, unsigned frontbuffer_bits);
>  
>  /* intel_dp_mst.c */
>  int intel_dp_mst_encoder_init(struct intel_digital_port *intel_dig_port, int conn_id);
> diff --git a/drivers/gpu/drm/i915/intel_frontbuffer.c b/drivers/gpu/drm/i915/intel_frontbuffer.c
> index 79f6d72..73cb6e0 100644
> --- a/drivers/gpu/drm/i915/intel_frontbuffer.c
> +++ b/drivers/gpu/drm/i915/intel_frontbuffer.c
> @@ -157,6 +157,7 @@ void intel_fb_obj_invalidate(struct drm_i915_gem_object *obj,
>  	intel_mark_fb_busy(dev, obj->frontbuffer_bits, ring);
>  
>  	intel_psr_invalidate(dev, obj->frontbuffer_bits);
> +	intel_edp_drrs_invalidate(dev, obj->frontbuffer_bits);
>  }
>  
>  /**
> @@ -182,6 +183,7 @@ void intel_frontbuffer_flush(struct drm_device *dev,
>  
>  	intel_mark_fb_busy(dev, frontbuffer_bits, NULL);
>  
> +	intel_edp_drrs_flush(dev, frontbuffer_bits);
>  	intel_psr_flush(dev, frontbuffer_bits);
>  
>  	/*
> -- 
> 2.0.1
> 

-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch