> -----Original Message-----
> From: Hogander, Jouni <jouni.hogander@xxxxxxxxx>
> Sent: Thursday, August 22, 2024 2:16 PM
> To: Kandpal, Suraj <suraj.kandpal@xxxxxxxxx>; intel-
> gfx@xxxxxxxxxxxxxxxxxxxxx
> Cc: Murthy, Arun R <arun.r.murthy@xxxxxxxxx>; Manna, Animesh
> <animesh.manna@xxxxxxxxx>; jani.nikula@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH 2/2] drm/i915/psr: Implment WA to help reach PC10
>
> On Wed, 2024-06-19 at 10:07 +0530, Suraj Kandpal wrote:
> > To reach PC10 when PKG_C_LATENCY is configure we must do the
> following
> > things
> > 1) Enter PSR1 only when delayed_vblank < 6 lines and DC5 can be
> > entered
> > 2) Allow PSR2 deep sleep when DC5 can be entered
> > 3) DC5 can be entered when all transocoder have either PSR1, PSR2 or
> > eDP 1.5 PR ALPM enabled and VBI is disabled and flips and pushes are
> > not happening.
> >
> > --v2
> > -Switch condition and do an early return [Jani] -Do some checks in
> > compute_config [Jani] -Do not use register reads as a method of
> > checking states for DPKGC or delayed vblank [Jani] -Use another way to
> > see is vblank interrupts are disabled or not [Jani]
> >
> > WA: 16023497226
> > Signed-off-by: Suraj Kandpal <suraj.kandpal@xxxxxxxxx>
> > ---
> > .../drm/i915/display/intel_display_types.h | 2 +
> > drivers/gpu/drm/i915/display/intel_psr.c | 82
> > ++++++++++++++++++-
> > 2 files changed, 83 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h
> > b/drivers/gpu/drm/i915/display/intel_display_types.h
> > index 46b3cbeb4a82..031f8e889b65 100644
> > --- a/drivers/gpu/drm/i915/display/intel_display_types.h
> > +++ b/drivers/gpu/drm/i915/display/intel_display_types.h
> > @@ -1708,6 +1708,8 @@ struct intel_psr {
> > bool sink_support;
> > bool source_support;
> > bool enabled;
> > + bool delayed_vblank;
> > + bool is_dpkgc_configured;
> > bool paused;
> > enum pipe pipe;
> > enum transcoder transcoder;
> > diff --git a/drivers/gpu/drm/i915/display/intel_psr.c
> > b/drivers/gpu/drm/i915/display/intel_psr.c
> > index 080bf5e51148..4ddea6737386 100644
> > --- a/drivers/gpu/drm/i915/display/intel_psr.c
> > +++ b/drivers/gpu/drm/i915/display/intel_psr.c
> > @@ -808,6 +808,73 @@ static u8 psr_compute_idle_frames(struct
> intel_dp
> > *intel_dp)
> > return idle_frames;
> > }
> >
> > +static bool intel_psr_check_delayed_vblank_limit(struct
> > intel_crtc_state *crtc_state)
> > +{
> > + struct drm_display_mode *adjusted_mode = &crtc_state-
> > >hw.adjusted_mode;
> > +
> > + return (adjusted_mode->crtc_vblank_start - adjusted_mode-
> > >crtc_vdisplay) >= 6;
> > +}
> > +
> > +/*
> > + * PKG_C_LATENCY is configured only when DISPLAY_VER >= 20 and
> > + * VRR is not enabled
> > + */
> > +static bool intel_psr_is_dpkgc_configured(struct drm_i915_private
> > *i915)
> > +{
> > + struct intel_crtc *intel_crtc;
> > +
> > + if (DISPLAY_VER(i915) < 20)
> > + return false;
> > +
> > + for_each_intel_crtc(&i915->drm, intel_crtc) {
> > + struct intel_crtc_state *crtc_state;
> > +
> > + if (!intel_crtc->active)
> > + continue;
> > +
> > + crtc_state = intel_crtc->config;
> > +
> > + if (crtc_state->vrr.enable)
> > + return false;
> > + }
> > +
> > + return true;
> > +}
> > +
> > +/*
> > + * DC5 entry is only possible if vblank interrupt is disabled
> > + * and either psr1, psr2, edp 1.5 pr alpm is enabled on all
> > + * enabled encoders.
> > + */
> > +static bool intel_psr_is_dc5_entry_possible(struct drm_i915_private
> > *i915)
> > +{
> > + struct intel_crtc *intel_crtc;
> > +
> > + for_each_intel_crtc(&i915->drm, intel_crtc) {
> > + struct intel_encoder *encoder;
> > + struct drm_crtc *crtc = &intel_crtc->base;
> > + struct drm_vblank_crtc *vblank;
> > +
> > + if (!intel_crtc->active)
> > + continue;
> > +
> > + vblank = drm_crtc_vblank_crtc(crtc);
> > +
> > + if (vblank->enabled)
> > + return false;
> > +
> > + for_each_encoder_on_crtc(&i915->drm, crtc, encoder) {
> > + struct intel_dp *intel_dp =
> > enc_to_intel_dp(encoder);
> > + struct intel_psr *psr = &intel_dp->psr;
> > +
> > + if (!psr->enabled)
> > + return false;
> > + }
> > + }
> > +
> > + return true;
> > +}
> > +
> > static bool hsw_activate_psr1(struct intel_dp *intel_dp)
> > {
> > struct drm_i915_private *dev_priv = dp_to_i915(intel_dp); @@
> > -815,6 +882,14 @@ static bool hsw_activate_psr1(struct intel_dp
> > *intel_dp)
> > u32 max_sleep_time = 0x1f;
> > u32 val = EDP_PSR_ENABLE;
> >
> > + /* WA: 16023497226*/
> > + if (intel_dp->psr.is_dpkgc_configured &&
> > + (intel_dp->psr.delayed_vblank ||
> > intel_psr_is_dc5_entry_possible(dev_priv))) {
> > + drm_dbg_kms(&dev_priv->drm,
> > + "PSR1 not activated as it doesn't meet
> > requirements of WA:16023497226\n");
> > + return false;
> > + }
> > +
>
> I would recommend doing this in intel_psr_compute_config as a last step
> and drop patch 1. Doing it this way would be safer as it's not opening new
> sequence/state where psr.enabled = true and psr.active = false after
> intel_psr_enable_locked.
The reason for this was I wanted to disable only psr1 based on if dc5 entry is possible or not.
Even if I call the dc5_entry_is_possible function from compute_config and save it in the intel_psr
state we would still end up with the seq psr.enabled = true and psr.active = false unless you see a
param which will only activate psr2 and not psr1 in such scenario ?
Regards,
Suraj Kandpal
>
> BR,
>
> Jouni Högander
>
> > val |=
> > EDP_PSR_IDLE_FRAMES(psr_compute_idle_frames(intel_dp));
> >
> > if (DISPLAY_VER(dev_priv) < 20) @@ -907,7 +982,10 @@ static
> > void hsw_activate_psr2(struct intel_dp
> > *intel_dp)
> > u32 val = EDP_PSR2_ENABLE;
> > u32 psr_val = 0;
> >
> > - val |=
> > EDP_PSR2_IDLE_FRAMES(psr_compute_idle_frames(intel_dp));
> > + /* WA: 16023497226*/
> > + if (intel_dp->psr.is_dpkgc_configured &&
> > + intel_psr_is_dc5_entry_possible(dev_priv))
> > + val |=
> > EDP_PSR2_IDLE_FRAMES(psr_compute_idle_frames(intel_dp));
> >
> > if (DISPLAY_VER(dev_priv) < 14 && !IS_ALDERLAKE_P(dev_priv))
> > val |= EDP_SU_TRACK_ENABLE; @@ -1502,6 +1580,8 @@ void
> > intel_psr_compute_config(struct intel_dp *intel_dp,
> > return;
> >
> > crtc_state->has_sel_update =
> > intel_sel_update_config_valid(intel_dp, crtc_state);
> > + intel_dp->psr.delayed_vblank =
> > intel_psr_check_delayed_vblank_limit(crtc_state);
> > + intel_dp->psr.is_dpkgc_configured =
> > intel_psr_is_dpkgc_configured(dev_priv);
> > }
> >
> > void intel_psr_get_config(struct intel_encoder *encoder,
