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

[Anshuamn Gupta]

On 2019-11-14 at 04:47:35 +0530, Souza, Jose wrote:
> 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>
Reviewed-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
> > >