[Intel-gfx] [PATCH 1/3] drm/i915/psr: Share the computation of idle frames

[Souza, Jose]

On Wed, 2019-11-13 at 18:04 +0530, Anshuamn Gupta wrote:
> Looks good to me, there is a minor comment see below.
> On 2019-10-31 at 17:14:20 -0700, José Roberto de Souza wrote:
> > Both activate functions and the dc3co disable function were doing
> > the
> > same thing, so better move to a function and share.
> > Also while at it adding a WARN_ON to catch invalid values.
> > 
> > Cc: Anshuman Gupta <anshuman.gupta at intel.com>
> > Cc: Imre Deak <imre.deak at intel.com>
> Acked-by: Anshuman Gupta <anshuman.gupta at intel.com>
> > Signed-off-by: José Roberto de Souza <jose.souza at intel.com>
> > ---
> >  drivers/gpu/drm/i915/display/intel_psr.c | 43 +++++++++++---------
> > ----
> >  1 file changed, 19 insertions(+), 24 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/i915/display/intel_psr.c
> > b/drivers/gpu/drm/i915/display/intel_psr.c
> > index 6a9f322d3fca..bb9b5349b72a 100644
> > --- a/drivers/gpu/drm/i915/display/intel_psr.c
> > +++ b/drivers/gpu/drm/i915/display/intel_psr.c
> > @@ -451,22 +451,29 @@ static u32 intel_psr1_get_tp_time(struct
> > intel_dp *intel_dp)
> >  	return val;
> >  }
> >  
> > -static void hsw_activate_psr1(struct intel_dp *intel_dp)
> > +static u8 psr_compute_idle_frames(struct intel_dp *intel_dp)
> >  {
> >  	struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
> > -	u32 max_sleep_time = 0x1f;
> > -	u32 val = EDP_PSR_ENABLE;
> > +	int idle_frames;
> >  
> >  	/* Let's use 6 as the minimum to cover all known cases
> > including the
> >  	 * off-by-one issue that HW has in some cases.
> >  	 */
> > -	int idle_frames = max(6, dev_priv->vbt.psr.idle_frames);
> > -
> > -	/* sink_sync_latency of 8 means source has to wait for more
> > than 8
> > -	 * frames, we'll go with 9 frames for now
> > -	 */
> > +	idle_frames = max(6, dev_priv->vbt.psr.idle_frames);
> >  	idle_frames = max(idle_frames, dev_priv->psr.sink_sync_latency
> > + 1);
> > -	val |= idle_frames << EDP_PSR_IDLE_FRAME_SHIFT;
> > +
> > +	WARN_ON(idle_frames > 0xf);
> > +
> > +	return idle_frames;
> there would be return type mismatch warning.

There is not warning, the value will be truncated but if happens we
will get the warn_on above.


> > +}
> > +
> > +static void hsw_activate_psr1(struct intel_dp *intel_dp)
> > +{
> > +	struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
> > +	u32 max_sleep_time = 0x1f;
> > +	u32 val = EDP_PSR_ENABLE;
> > +
> > +	val |= psr_compute_idle_frames(intel_dp) <<
> > EDP_PSR_IDLE_FRAME_SHIFT;
> >  
> >  	val |= max_sleep_time << EDP_PSR_MAX_SLEEP_TIME_SHIFT;
> >  	if (IS_HASWELL(dev_priv))
> > @@ -490,13 +497,7 @@ static void hsw_activate_psr2(struct intel_dp
> > *intel_dp)
> >  	struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
> >  	u32 val;
> >  
> > -	/* Let's use 6 as the minimum to cover all known cases
> > including the
> > -	 * off-by-one issue that HW has in some cases.
> > -	 */
> > -	int idle_frames = max(6, dev_priv->vbt.psr.idle_frames);
> > -
> > -	idle_frames = max(idle_frames, dev_priv->psr.sink_sync_latency
> > + 1);
> > -	val = idle_frames << EDP_PSR2_IDLE_FRAME_SHIFT;
> > +	val = psr_compute_idle_frames(intel_dp) <<
> > EDP_PSR2_IDLE_FRAME_SHIFT;
> >  
> >  	val |= EDP_PSR2_ENABLE | EDP_SU_TRACK_ENABLE;
> >  	if (INTEL_GEN(dev_priv) >= 10 || IS_GEMINILAKE(dev_priv))
> > @@ -563,16 +564,10 @@ static void tgl_psr2_enable_dc3co(struct
> > drm_i915_private *dev_priv)
> >  
> >  static void tgl_psr2_disable_dc3co(struct drm_i915_private
> > *dev_priv)
> >  {
> > -	int idle_frames;
> > +	struct intel_dp *intel_dp = dev_priv->psr.dp;
> >  
> >  	intel_display_power_set_target_dc_state(dev_priv,
> > DC_STATE_EN_UPTO_DC6);
> > -	/*
> > -	 * Restore PSR2 idle frame let's use 6 as the minimum to cover
> > all known
> > -	 * cases including the off-by-one issue that HW has in some
> > cases.
> > -	 */
> > -	idle_frames = max(6, dev_priv->vbt.psr.idle_frames);
> > -	idle_frames = max(idle_frames, dev_priv->psr.sink_sync_latency
> > + 1);
> > -	psr2_program_idle_frames(dev_priv, idle_frames);
> > +	psr2_program_idle_frames(dev_priv,
> > psr_compute_idle_frames(intel_dp));
> >  }
> >  
> >  static void tgl_dc5_idle_thread(struct work_struct *work)
> > -- 
> > 2.23.0
> >