[Intel-gfx] [PATCH 10/13] drm/i915: fix the CFB size check

[Zanoni, Paulo R]

Em Ter, 2015-11-10 às 11:22 +0100, Maarten Lankhorst escreveu:
> Op 04-11-15 om 20:10 schreef Paulo Zanoni:
> > In function find_compression_threshold() we try to over-allocate
> > CFB
> > space in order to reudce reallocations and fragmentation, and we're
> > not considering that at the CFB size check. Consider it.
> > 
> > There is also a longer-term plan to kill
> > dev_priv->fbc.uncompressed_size, but this will come later.
> > 
> > Signed-off-by: Paulo Zanoni <paulo.r.zanoni at intel.com>
> > ---
> >  drivers/gpu/drm/i915/intel_fbc.c | 3 ++-
> >  1 file changed, 2 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/gpu/drm/i915/intel_fbc.c
> > b/drivers/gpu/drm/i915/intel_fbc.c
> > index dee99c9..e99aacc 100644
> > --- a/drivers/gpu/drm/i915/intel_fbc.c
> > +++ b/drivers/gpu/drm/i915/intel_fbc.c
> > @@ -719,7 +719,8 @@ static int intel_fbc_setup_cfb(struct
> > intel_crtc *crtc)
> >  	size = intel_fbc_calculate_cfb_size(crtc);
> >  	cpp = drm_format_plane_cpp(fb->pixel_format, 0);
> >  
> > -	if (size <= dev_priv->fbc.uncompressed_size)
> > +	if (dev_priv->fbc.compressed_fb.allocated &&
> > +	    size <= dev_priv->fbc.compressed_fb.size * dev_priv-
> > >fbc.threshold)
> >  		return 0;
> >  
> >  	/* Release any current block */
> Should i8xx_fbc_enable be changed too then?

As far as I understand, no. We're just reserving a bigger buffer in
case we need it later, but the size used by the hardware is still the
same. But I'm not 100% sure the i8xx code is actually correct since I
didn't dig deep into the ancient scrolls. By not touching i8xx we're
also avoiding a possible new regression.

> 
> Rest of the patches look ok, applied those.