On Wed, Nov 17, 2021 at 01:10:13PM -0800, Navare, Manasi wrote: > On Wed, Nov 17, 2021 at 08:31:02PM +0200, Ville Syrjala wrote: > > From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > > > > Let's adjust the vblank evasion to account for the case where > > a push has already been sent. In that case the vblank exit will start > > at vmin vblank start (as opposed to vmax vblank start when no push > > has been sent). > > > > This should minimize the effects of the tiny race between sampling > > the frame counter vs. intel_vrr_send_push() during the previous frame. > > This will also be required if we want to do mailbox style updates with > > vrr since then we'd definitely do multiple commits per frame. Currently > > mailbox updates are only used by the legacy cursor, but we don't do > > vrr push for those. > > > > Cc: Manasi Navare <manasi.d.navare@xxxxxxxxx> > > Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > > --- > > drivers/gpu/drm/i915/display/intel_crtc.c | 10 +++++++--- > > drivers/gpu/drm/i915/display/intel_vrr.c | 12 ++++++++++++ > > drivers/gpu/drm/i915/display/intel_vrr.h | 1 + > > 3 files changed, 20 insertions(+), 3 deletions(-) > > > > diff --git a/drivers/gpu/drm/i915/display/intel_crtc.c b/drivers/gpu/drm/i915/display/intel_crtc.c > > index cf403be7736c..eb5444f90e77 100644 > > --- a/drivers/gpu/drm/i915/display/intel_crtc.c > > +++ b/drivers/gpu/drm/i915/display/intel_crtc.c > > @@ -470,10 +470,14 @@ void intel_pipe_update_start(struct intel_crtc_state *new_crtc_state) > > if (intel_crtc_needs_vblank_work(new_crtc_state)) > > intel_crtc_vblank_work_init(new_crtc_state); > > > > - if (new_crtc_state->vrr.enable) > > - vblank_start = intel_vrr_vmax_vblank_start(new_crtc_state); > > - else > > + if (new_crtc_state->vrr.enable) { > > + if (intel_vrr_is_push_sent(new_crtc_state)) > > + vblank_start = intel_vrr_vmin_vblank_start(new_crtc_state); > > Actually if Push is sent then the vblank gets terminated at that point which falls between vmin and vmax so > not necessarily at Vmin but at anytime between vmin and vmax. Is it correct to calculate it based on vmin? If you do a push between vmin and vmax then the vblank terminates immediately and the PUSH_SEND bit gets cleared. The only way the bit stays set is you set it after vmax/before vmin. > > > + else > > + vblank_start = intel_vrr_vmax_vblank_start(new_crtc_state); > > + } else { > > vblank_start = intel_mode_vblank_start(adjusted_mode); > > + } > > > > /* FIXME needs to be calibrated sensibly */ > > min = vblank_start - intel_usecs_to_scanlines(adjusted_mode, > > diff --git a/drivers/gpu/drm/i915/display/intel_vrr.c b/drivers/gpu/drm/i915/display/intel_vrr.c > > index c335b1dbafcf..db1c3902fc2d 100644 > > --- a/drivers/gpu/drm/i915/display/intel_vrr.c > > +++ b/drivers/gpu/drm/i915/display/intel_vrr.c > > @@ -193,6 +193,18 @@ void intel_vrr_send_push(const struct intel_crtc_state *crtc_state) > > TRANS_PUSH_EN | TRANS_PUSH_SEND); > > } > > > > +bool intel_vrr_is_push_sent(const struct intel_crtc_state *crtc_state) > > +{ > > + struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc); > > + struct drm_i915_private *dev_priv = to_i915(crtc->base.dev); > > + enum transcoder cpu_transcoder = crtc_state->cpu_transcoder; > > + > > + if (!crtc_state->vrr.enable) > > + return false; > > + > > + return intel_de_read(dev_priv, TRANS_PUSH(cpu_transcoder)) & TRANS_PUSH_SEND; > > But HW clears this bit after double buffer update. Is this a good inidcation to check the PUSH_SEND bit? > > Manasi > > > +} > > + > > void intel_vrr_disable(const struct intel_crtc_state *old_crtc_state) > > { > > struct intel_crtc *crtc = to_intel_crtc(old_crtc_state->uapi.crtc); > > diff --git a/drivers/gpu/drm/i915/display/intel_vrr.h b/drivers/gpu/drm/i915/display/intel_vrr.h > > index 96f9c9c27ab9..1c2da572693d 100644 > > --- a/drivers/gpu/drm/i915/display/intel_vrr.h > > +++ b/drivers/gpu/drm/i915/display/intel_vrr.h > > @@ -23,6 +23,7 @@ void intel_vrr_compute_config(struct intel_crtc_state *crtc_state, > > void intel_vrr_enable(struct intel_encoder *encoder, > > const struct intel_crtc_state *crtc_state); > > void intel_vrr_send_push(const struct intel_crtc_state *crtc_state); > > +bool intel_vrr_is_push_sent(const struct intel_crtc_state *crtc_state); > > void intel_vrr_disable(const struct intel_crtc_state *old_crtc_state); > > void intel_vrr_get_config(struct intel_crtc *crtc, > > struct intel_crtc_state *crtc_state); > > -- > > 2.32.0 > > -- Ville Syrjälä Intel