[Intel-gfx] [RFC v2] drm/i915: lpsp with hdmi/dp outputs

[Gupta, Anshuman]

> -----Original Message-----
> From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> Sent: Friday, April 30, 2021 11:10 PM
> To: Gupta, Anshuman <anshuman.gupta at intel.com>
> Cc: intel-gfx at lists.freedesktop.org; Kai Vehmanen
> <kai.vehmanen at linux.intel.com>; Shankar, Uma <uma.shankar at intel.com>
> Subject: Re: [RFC v2] drm/i915: lpsp with hdmi/dp outputs
> 
> On Fri, Apr 30, 2021 at 05:23:55PM +0530, Anshuman Gupta wrote:
> > DG1 and DISPLAY_VER=13 onwards Audio MMIO/VERBS lies in PG0 power
> > well. So in order to detect audio capable DP/HDMI output it doesn't
> > require to enable PG3 power well on DG1 and PG2 on DISPLAY_VER=13
> > pltform. It will save the power when DP/HDMI outputs used as lpsp
> > configuration.
> >
> > B.Spec: 49233
> > B.Spec: 49231
> >
> > Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > Cc: Kai Vehmanen <kai.vehmanen at linux.intel.com>
> > Cc: Uma Shankar <uma.shankar at intel.com>
> > Signed-off-by: Anshuman Gupta <anshuman.gupta at intel.com>
> > ---
> >  drivers/gpu/drm/i915/display/intel_display.c | 9 +++++++--
> >  1 file changed, 7 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_display.c
> > b/drivers/gpu/drm/i915/display/intel_display.c
> > index 6280ba7f4c17..16bfa7628970 100644
> > --- a/drivers/gpu/drm/i915/display/intel_display.c
> > +++ b/drivers/gpu/drm/i915/display/intel_display.c
> > @@ -3536,8 +3536,13 @@ static u64 get_crtc_power_domains(struct
> intel_crtc_state *crtc_state)
> >  		mask |= BIT_ULL(intel_encoder->power_domain);
> >  	}
> >
> > -	if (HAS_DDI(dev_priv) && crtc_state->has_audio)
> > -		mask |= BIT_ULL(POWER_DOMAIN_AUDIO);
> > +	if (HAS_DDI(dev_priv) && crtc_state->has_audio) {
> > +		/* if Audio mmio/verbs lies in PG0 */
> > +		if (IS_DG1(dev_priv) || DISPLAY_VER(dev_priv) >= 11)
> > +			mask |= BIT_ULL(POWER_DOMAIN_DISPLAY_CORE);
> > +		else
> > +			mask |= BIT_ULL(POWER_DOMAIN_AUDIO);
> 
> Power domains are supposed to be abstract. So if the audio stuff is moving to a
> different power well then we just need to adjust the domain for the relevant
> power wells.
Currently we have same power well for DG1 and TGL, this particular delta has been introduced 
from DG1 onwards and this delta is present for DISPLAY_VER 13 as well.
So in order to adjust this delta for DG1 , we will require a separate power well meta data for DG1.
@imre could you please provide your input to handle above delta on DG1.
How about breaking down POWER_DOMAIN_AUDIO to POWER_DOMAIN_AUDIO_VERBS and 
POWER_DOMAIN_AUDIO_PLAYBACK?
Thanks,
Anshuman Gupta.
> 
> > +	}
> >
> >  	if (crtc_state->shared_dpll)
> >  		mask |= BIT_ULL(POWER_DOMAIN_DISPLAY_CORE);
> > --
> > 2.26.2
> 
> --
> Ville Syrjälä
> Intel