Re: [PATCH] drm/i915/psr: Check PSR pause counter in __psr_wait_for_idle_locked

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

On Tue, 2025-08-26 at 08:29 +0000, B, Jeevan wrote:
> LGTM 
> 
> Reviewed-by: Jeevan B <jeevan.b@intel.com>

Thank you Jeevan for your review. This is now pushed to drm-intel-next.

BR,

Jouni Högander

> 
> > -----Original Message-----
> > From: Intel-gfx <intel-gfx-bounces@lists.freedesktop.org> On Behalf
> > Of Jouni
> > Högander
> > Sent: Tuesday, August 26, 2025 1:15 PM
> > To: intel-gfx@lists.freedesktop.org; intel-xe@lists.freedesktop.org
> > Cc: Hogander, Jouni <jouni.hogander@intel.com>
> > Subject: [PATCH] drm/i915/psr: Check PSR pause counter in
> > __psr_wait_for_idle_locked
> > 
> > PSR work is using __psr_wait_for_idle_locked to ensure PSR exit is
> > completed
> > before continuing to PSR activation. __psr_wait_for_idle_locked is
> > unlocking
> > PSR mutex which allows PSR disable/enable and PSR pause/resume
> > while PSR
> > idle is being wait. PSR enable status is already checked after
> > locking again PSR
> > mutex but PSR pause counter check is missing. Due to this PSR work
> > may
> > continue to PSR activation even PSR is paused.
> > 
> > Fix this by checking PSR pause counter in
> > __psr_wait_for_idle_locked after PSR
> > mutex is locked again.
> > 
> > Signed-off-by: Jouni Högander <jouni.hogander@intel.com>
> > ---
> >  drivers/gpu/drm/i915/display/intel_psr.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/drivers/gpu/drm/i915/display/intel_psr.c
> > b/drivers/gpu/drm/i915/display/intel_psr.c
> > index eec4f7dc2d66..8b4cdf9b30db 100644
> > --- a/drivers/gpu/drm/i915/display/intel_psr.c
> > +++ b/drivers/gpu/drm/i915/display/intel_psr.c
> > @@ -3092,7 +3092,7 @@ static bool __psr_wait_for_idle_locked(struct
> > intel_dp *intel_dp)
> > 
> >  	/* After the unlocked wait, verify that PSR is still
> > wanted! */
> >  	mutex_lock(&intel_dp->psr.lock);
> > -	return err == 0 && intel_dp->psr.enabled;
> > +	return err == 0 && intel_dp->psr.enabled &&
> > +!intel_dp->psr.pause_counter;
> >  }
> > 
> >  static int intel_psr_fastset_force(struct intel_display *display)
> > --
> > 2.43.0
>