[Intel-gfx] [PATCH 02/12] drm/i915: Calculate watermark related members in the crtc_state, v3.

[Ander Conselvan De Oliveira]

On Tue, 2015-11-24 at 15:55 +0100, Maarten Lankhorst wrote:
> Op 24-11-15 om 15:03 schreef Ander Conselvan De Oliveira:
> > On Thu, 2015-11-19 at 16:07 +0100, Maarten Lankhorst wrote:
> > > This removes pre/post_wm_update from intel_crtc->atomic, and
> > > creates atomic state for it in intel_crtc.
> > > 
> > > Changes since v1:
> > > - Rebase on top of wm changes.
> > > Changes since v2:
> > > - Split disable_cxsr into a separate patch.
> > > 
> > > Signed-off-by: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
> > > ---
> > >  drivers/gpu/drm/i915/intel_atomic.c  |  1 +
> > >  drivers/gpu/drm/i915/intel_display.c | 31 +++++++++++++------------------
> > >  drivers/gpu/drm/i915/intel_drv.h     |  2 +-
> > >  3 files changed, 15 insertions(+), 19 deletions(-)
> > > 
> > > diff --git a/drivers/gpu/drm/i915/intel_atomic.c
> > > b/drivers/gpu/drm/i915/intel_atomic.c
> > > index 9f0638a37b6d..4625f8a9ba12 100644
> > > --- a/drivers/gpu/drm/i915/intel_atomic.c
> > > +++ b/drivers/gpu/drm/i915/intel_atomic.c
> > > @@ -96,6 +96,7 @@ intel_crtc_duplicate_state(struct drm_crtc *crtc)
> > >  	crtc_state->update_pipe = false;
> > >  	crtc_state->disable_lp_wm = false;
> > >  	crtc_state->disable_cxsr = false;
> > > +	crtc_state->wm_changed = false;
> > >  
> > >  	return &crtc_state->base;
> > >  }
> > > diff --git a/drivers/gpu/drm/i915/intel_display.c
> > > b/drivers/gpu/drm/i915/intel_display.c
> > > index 5ee64e67ad8a..db4995406277 100644
> > > --- a/drivers/gpu/drm/i915/intel_display.c
> > > +++ b/drivers/gpu/drm/i915/intel_display.c
> > > @@ -4741,6 +4741,8 @@ intel_pre_disable_primary(struct drm_crtc *crtc)
> > >  static void intel_post_plane_update(struct intel_crtc *crtc)
> > >  {
> > >  	struct intel_crtc_atomic_commit *atomic = &crtc->atomic;
> > > +	struct intel_crtc_state *pipe_config =
> > > +		to_intel_crtc_state(crtc->base.state);
> > >  	struct drm_device *dev = crtc->base.dev;
> > >  	struct drm_i915_private *dev_priv = dev->dev_private;
> > >  
> > > @@ -4751,7 +4753,7 @@ static void intel_post_plane_update(struct
> > > intel_crtc
> > > *crtc)
> > >  
> > >  	crtc->wm.cxsr_allowed = true;
> > >  
> > > -	if (crtc->atomic.update_wm_post)
> > > +	if (pipe_config->wm_changed)
> > >  		intel_update_watermarks(&crtc->base);
> > This adds an extra call to intel_update_watermarks() for the case where
> > previously update_wm_pre would be set. This won't cause extra register
> > writes
> > because of the dirty check, but I think it deserves a note in the commit
> > message.
> I think intel_update_watermarks needs to be fixed to take a crtc_state and
> whether pre/post commit is used.
> 
> It looks to me like doing anything else could bug if watermarks are changed
> with 1 plane becoming visible and the other invisible..
> > >  
> > >  	if (atomic->update_fbc)
> > > @@ -4784,6 +4786,9 @@ static void intel_pre_plane_update(struct intel_crtc
> > > *crtc)
> > >  		crtc->wm.cxsr_allowed = false;
> > >  		intel_set_memory_cxsr(dev_priv, false);
> > >  	}
> > > +
> > > +	if (!needs_modeset(&pipe_config->base) && pipe_config
> > > ->wm_changed)
> > > +		intel_update_watermarks(&crtc->base);
> > >  }
> > >  
> > >  static void intel_crtc_disable_planes(struct drm_crtc *crtc, unsigned
> > > plane_mask)
> > > @@ -11706,25 +11711,18 @@ int intel_plane_atomic_calc_changes(struct
> > > drm_crtc_state *crtc_state,
> > >  			 plane->base.id, was_visible, visible,
> > >  			 turn_off, turn_on, mode_changed);
> > >  
> > > -	if (turn_on) {
> > > -		intel_crtc->atomic.update_wm_pre = true;
> > > -		/* must disable cxsr around plane enable/disable */
> > > -		if (plane->type != DRM_PLANE_TYPE_CURSOR) {
> > > -			pipe_config->disable_cxsr = true;
> > > -			/* to potentially re-enable cxsr */
> > > -			intel_crtc->atomic.wait_vblank = true;
> > > -			intel_crtc->atomic.update_wm_post = true;
> > > -		}
> > > -	} else if (turn_off) {
> > > -		intel_crtc->atomic.update_wm_post = true;
> > > +	if (turn_on || turn_off) {
> > > +		pipe_config->wm_changed = true;
> > > +
> > >  		/* must disable cxsr around plane enable/disable */
> > >  		if (plane->type != DRM_PLANE_TYPE_CURSOR) {
> > >  			if (is_crtc_enabled)
> > >  				intel_crtc->atomic.wait_vblank = true;
> > >  			pipe_config->disable_cxsr = true;
> > >  		}
> > > -	} else if (intel_wm_need_update(plane, plane_state)) {
> > > -		intel_crtc->atomic.update_wm_pre = true;
> > > +	} else if ((was_visible || visible) &&
> > So this avoids watermark changes when the plane is not visible before or
> > after
> > the update. Wouldn't it be better to fix intel_wm_need_update() instead if
> > returns true in that case?
> 
> If visible is changed wm_changed = true is always set. It would go through the
> (turn_on || turn_off) case.
> 
> I guess checking was_visible || visible is overkill, and could be changed to
> just visible && intel_wm_need_update(plane, plane_state).

What I meant is that I find odd that intel_wm_need_update() returns true when
both was_visible and visible is false. Since that function is supposed to
compare two plane states and tell us if a wm update is needed, I'd rather add
the visible check there.