[Intel-gfx] [PATCH 2/2] drm/i915: Reuse intel_adjusted_rate() for pfit pixel rate adjustment

[Ville Syrjälä]

On Thu, Apr 01, 2021 at 03:55:20PM +0300, Jani Nikula wrote:
> On Tue, 30 Mar 2021, Ville Syrjala <ville.syrjala at linux.intel.com> wrote:
> > From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> >
> > Replace the hand rolled pfit downscale calculations with
> > intel_adjusted_rate().
> >
> > Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > ---
> >  .../gpu/drm/i915/display/intel_atomic_plane.c |  6 ++---
> >  .../gpu/drm/i915/display/intel_atomic_plane.h |  4 ++++
> >  drivers/gpu/drm/i915/display/intel_display.c  | 23 +++++--------------
> >  3 files changed, 13 insertions(+), 20 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_atomic_plane.c b/drivers/gpu/drm/i915/display/intel_atomic_plane.c
> > index 3f830b70b0c1..5f0a5ea474eb 100644
> > --- a/drivers/gpu/drm/i915/display/intel_atomic_plane.c
> > +++ b/drivers/gpu/drm/i915/display/intel_atomic_plane.c
> > @@ -133,9 +133,9 @@ intel_plane_destroy_state(struct drm_plane *plane,
> >  	kfree(plane_state);
> >  }
> >  
> > -static unsigned int intel_adjusted_rate(const struct drm_rect *src,
> > -					const struct drm_rect *dst,
> > -					unsigned int rate)
> > +unsigned int intel_adjusted_rate(const struct drm_rect *src,
> > +				 const struct drm_rect *dst,
> > +				 unsigned int rate)
> >  {
> >  	unsigned int src_w, src_h, dst_w, dst_h;
> >  
> > diff --git a/drivers/gpu/drm/i915/display/intel_atomic_plane.h b/drivers/gpu/drm/i915/display/intel_atomic_plane.h
> > index 5c78a087ed86..dc4d05e75e1c 100644
> > --- a/drivers/gpu/drm/i915/display/intel_atomic_plane.h
> > +++ b/drivers/gpu/drm/i915/display/intel_atomic_plane.h
> > @@ -10,6 +10,7 @@
> >  
> >  struct drm_plane;
> >  struct drm_property;
> > +struct drm_rect;
> >  struct intel_atomic_state;
> >  struct intel_crtc;
> >  struct intel_crtc_state;
> > @@ -18,6 +19,9 @@ struct intel_plane_state;
> >  
> >  extern const struct drm_plane_helper_funcs intel_plane_helper_funcs;
> >  
> > +unsigned int intel_adjusted_rate(const struct drm_rect *src,
> > +				 const struct drm_rect *dst,
> > +				 unsigned int rate);
> >  unsigned int intel_plane_pixel_rate(const struct intel_crtc_state *crtc_state,
> >  				    const struct intel_plane_state *plane_state);
> >  
> > diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
> > index d74b263c5f4e..472e691286c6 100644
> > --- a/drivers/gpu/drm/i915/display/intel_display.c
> > +++ b/drivers/gpu/drm/i915/display/intel_display.c
> > @@ -3978,7 +3978,7 @@ static bool intel_crtc_supports_double_wide(const struct intel_crtc *crtc)
> >  static u32 ilk_pipe_pixel_rate(const struct intel_crtc_state *crtc_state)
> >  {
> >  	u32 pixel_rate = crtc_state->hw.pipe_mode.crtc_clock;
> > -	unsigned int pipe_w, pipe_h, pfit_w, pfit_h;
> > +	struct drm_rect src;
> >  
> >  	/*
> >  	 * We only use IF-ID interlacing. If we ever use
> > @@ -3988,23 +3988,12 @@ static u32 ilk_pipe_pixel_rate(const struct intel_crtc_state *crtc_state)
> >  	if (!crtc_state->pch_pfit.enabled)
> >  		return pixel_rate;
> >  
> > -	pipe_w = crtc_state->pipe_src_w;
> > -	pipe_h = crtc_state->pipe_src_h;
> > +	drm_rect_init(&src, 0, 0,
> > +		      crtc_state->pipe_src_w << 16,
> > +		      crtc_state->pipe_src_h << 16);
> >  
> > -	pfit_w = drm_rect_width(&crtc_state->pch_pfit.dst);
> > -	pfit_h = drm_rect_height(&crtc_state->pch_pfit.dst);
> > -
> > -	if (pipe_w < pfit_w)
> > -		pipe_w = pfit_w;
> 
> So this is src_w = max(src_w, dst_w) and gets turned into dst_w =
> min(src_w, dst_w) instead? Ditto for _h. Does it end up being the same
> thing after the division?

Yes. The min/max just gets rid of the upscaling case,
ie. causes the division to be just x/x==1 when dst>src.
Doesn't matter if we use the min or max approach to
achieve that result.

-- 
Ville Syrjälä
Intel