Re: [PATCH] drm/i915/psr: Do not unnecessarily remove underrun on idle PSR WA

["Hogander, Jouni" <jouni.hogander@intel.com>]

On Mon, 2025-08-25 at 06:30 +0000, Shankar, Uma wrote:
> 
> 
> > -----Original Message-----
> > From: Hogander, Jouni <jouni.hogander@intel.com>
> > Sent: Friday, August 22, 2025 4:29 PM
> > To: intel-gfx@lists.freedesktop.org; intel-xe@lists.freedesktop.org
> > Cc: Shankar, Uma <uma.shankar@intel.com>; Hogander, Jouni
> > <jouni.hogander@intel.com>
> > Subject: [PATCH] drm/i915/psr: Do not unnecessarily remove underrun
> > on idle
> > PSR WA
> > 
> > We are currently removing underrun on idle PSR WA even if it's not
> > applied. Fix
> > this by checking pkg_c_latency_used on PSR exit as well.
> > 
> > Fixes: 9b1795e9b0ae ("drm/i915/psr: Underrun on idle PSR wa only
> > when pkgc
> > latency > delayed vblank")
> > Signed-off-by: Jouni Högander <jouni.hogander@intel.com>
> > ---
> >  drivers/gpu/drm/i915/display/intel_psr.c | 5 +++--
> >  1 file changed, 3 insertions(+), 2 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/i915/display/intel_psr.c
> > b/drivers/gpu/drm/i915/display/intel_psr.c
> > index b4091d28e814..88eceb8f00fd 100644
> > --- a/drivers/gpu/drm/i915/display/intel_psr.c
> > +++ b/drivers/gpu/drm/i915/display/intel_psr.c
> > @@ -2090,8 +2090,9 @@ static void intel_psr_exit(struct intel_dp
> > *intel_dp)
> > 
> >  		drm_WARN_ON(display->drm, !(val &
> > EDP_PSR2_ENABLE));
> >  	} else {
> > -		if (DISPLAY_VER(display) == 20 ||
> > -		    IS_DISPLAY_VERx100_STEP(display, 3000,
> > STEP_A0,
> > STEP_B0))
> > +		if ((DISPLAY_VER(display) == 20 ||
> > +		     IS_DISPLAY_VERx100_STEP(display, 3000,
> > STEP_A0,
> > STEP_B0)) &&
> > +			intel_dp->psr.pkg_c_latency_used)
> > 
> 
> Looks Good to me.
> Reviewed-by: Uma Shankar <uma.shankar@intel.com>

Thank you Uma. This is now pushed to drm-intel-next.

BR,

Jouni Högander

> 
> > 	intel_dmc_start_pkgc_exit_at_start_of_undelayed_vblank(dis
> > play,
> >  								  
> >      intel_dp-
> > > psr.pipe,
> >  								  
> >      false);
> > --
> > 2.43.0
>