On Fri, Jan 24, 2025 at 12:56:23PM +0200, Jouni Högander wrote: > We may have commit which doesn't have any non-arming plane register > writes. In that case there aren't "Frame Change" event before DSB vblank > evasion which hangs as PIPEDSL register is reading as 0 when PSR state is > SRDENT(PSR1) or DEEP_SLEEP(PSR2). Handle this by adding dummy write > triggering the "Frame Change" event. > > Signed-off-by: Jouni Högander <jouni.hogander@xxxxxxxxx> > --- > drivers/gpu/drm/i915/display/intel_display.c | 10 ++++++++++ > 1 file changed, 10 insertions(+) > > diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c > index a189aa437d972..cd7e960bd29f1 100644 > --- a/drivers/gpu/drm/i915/display/intel_display.c > +++ b/drivers/gpu/drm/i915/display/intel_display.c > @@ -7666,6 +7666,7 @@ static void intel_atomic_dsb_finish(struct intel_atomic_state *state, > intel_atomic_get_old_crtc_state(state, crtc); > struct intel_crtc_state *new_crtc_state = > intel_atomic_get_new_crtc_state(state, crtc); > + struct intel_display *display = to_intel_display(crtc); > > if (!new_crtc_state->hw.active) > return; > @@ -7708,6 +7709,15 @@ static void intel_atomic_dsb_finish(struct intel_atomic_state *state, > intel_crtc_planes_update_noarm(new_crtc_state->dsb_commit, > state, crtc); > > + /* > + * Ensure we have "Frame Change" event when PSR state is > + * SRDENT(PSR1) or DEEP_SLEEP(PSR2). Otherwise DSB vblank > + * evasion hangs as PIPEDSL is reading as 0. > + */ > + if (new_crtc_state->has_psr && !new_crtc_state->has_panel_replay) > + intel_de_write_dsb(display, new_crtc_state->dsb_commit, > + CURSURFLIVE(display, crtc->pipe), 0); I don't really want to see the low level detais right here. So we should probably should stuff this into some kind of intel_dsb_ensure_psr_frame_change() function or something along those lines. > + > intel_dsb_vblank_evade(state, new_crtc_state->dsb_commit); > > if (intel_crtc_needs_color_update(new_crtc_state)) > -- > 2.43.0 -- Ville Syrjälä Intel
