Re: [Intel-gfx] [PATCH 09/13] drm/i915/dsb: Don't use DSB to load the LUTs during full modeset

["Ville Syrjälä" <ville.syrjala@linux.intel.com>]

On Fri, Feb 03, 2023 at 10:04:17AM +0000, Manna, Animesh wrote:
> 
> 
> > -----Original Message-----
> > From: Intel-gfx <intel-gfx-bounces@lists.freedesktop.org> On Behalf Of Ville
> > Syrjala
> > Sent: Wednesday, January 18, 2023 10:01 PM
> > To: intel-gfx@lists.freedesktop.org
> > Subject: [Intel-gfx] [PATCH 09/13] drm/i915/dsb: Don't use DSB to load the
> > LUTs during full modeset
> > 
> > From: Ville Syrjälä <ville.syrjala@linux.intel.com>
> > 
> > Using the DSB for LUT loading during full modesets would require some
> > actual though. Let's just use mmio for the time being.
> > 
> > Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
> > ---
> >  drivers/gpu/drm/i915/display/intel_color.c | 4 ++++
> >  1 file changed, 4 insertions(+)
> > 
> > diff --git a/drivers/gpu/drm/i915/display/intel_color.c
> > b/drivers/gpu/drm/i915/display/intel_color.c
> > index f4a527a3c265..cab8dfd03853 100644
> > --- a/drivers/gpu/drm/i915/display/intel_color.c
> > +++ b/drivers/gpu/drm/i915/display/intel_color.c
> > @@ -1383,6 +1383,10 @@ void intel_color_prepare_commit(struct
> > intel_crtc_state *crtc_state)
> >  	/* FIXME DSB has issues loading LUTs, disable it for now */
> >  	return;
> > 
> > +	if (!crtc_state->hw.active ||
> > +	    intel_crtc_needs_modeset(crtc_state))
> > +		return;
> 
> Is it causing any issue ? Did not get the advantage of MMIO over DSB during modeset.

Integrating DSB usage into the modeset path would require actual
thought.

-- 
Ville Syrjälä
Intel