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); + intel_dsb_vblank_evade(state, new_crtc_state->dsb_commit); if (intel_crtc_needs_color_update(new_crtc_state)) -- 2.43.0
