Re: [PATCH 08/19] drm/i915/dp: Add a helper to decide if AS SDP can be used

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

On Mon, Mar 30, 2026 at 09:21:42PM +0300, Ville Syrjälä wrote:
> On Mon, Mar 30, 2026 at 09:36:45AM +0530, Ankit Nautiyal wrote:
> > Add a helper that determines whether AS SDP can be used for the
> > current DP configuration. For now this is true only when the sink
> > supports AS SDP and VRR is enabled, but more conditions may be added
> > later.
> > 
> > Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
> > ---
> >  drivers/gpu/drm/i915/display/intel_dp.c | 11 ++++++++++-
> >  1 file changed, 10 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
> > index 499850c2abcf..7ca3f9d583db 100644
> > --- a/drivers/gpu/drm/i915/display/intel_dp.c
> > +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> > @@ -3124,6 +3124,15 @@ static void intel_dp_compute_vsc_colorimetry(const struct intel_crtc_state *crtc
> >  	vsc->content_type = DP_CONTENT_TYPE_NOT_DEFINED;
> >  }
> >  
> > +static bool intel_dp_can_use_as_sdp(struct intel_dp *intel_dp,
> > +				    struct intel_crtc_state *crtc_state)

Hmm. Maybe the name should be .._need_as_sdp() or something like that
instead. I can imagine many cases when we could use the AS SDP but don't
have to.

> > +{
> > +	if (!intel_dp->as_sdp_supported)
> > +		return false;
> > +
> 
> Could have a FIXME here about fastset being borked with this. Didn't
> read far enough in the series yet to see if you did anything about that.
> 
> Either way
> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
> 
> > +	return crtc_state->vrr.enable;
> > +}
> > +
> >  static void intel_dp_compute_as_sdp(struct intel_dp *intel_dp,
> >  				    struct intel_crtc_state *crtc_state)
> >  {
> > @@ -3131,7 +3140,7 @@ static void intel_dp_compute_as_sdp(struct intel_dp *intel_dp,
> >  	const struct drm_display_mode *adjusted_mode =
> >  		&crtc_state->hw.adjusted_mode;
> >  
> > -	if (!crtc_state->vrr.enable || !intel_dp->as_sdp_supported)
> > +	if (!intel_dp_can_use_as_sdp(intel_dp, crtc_state))
> >  		return;
> >  
> >  	crtc_state->infoframes.enable |= intel_hdmi_infoframe_enable(DP_SDP_ADAPTIVE_SYNC);
> > -- 
> > 2.45.2
> 
> -- 
> Ville Syrjälä
> Intel

-- 
Ville Syrjälä
Intel