diff mbox series

[v5,12/13] drm/i915/display: Ensure we have "Frame Change" event in DSB commit

Message ID 20250124113906.850488-13-jouni.hogander@intel.com (mailing list archive)
State New
Headers show
Series PSR DSB support | expand

Commit Message

Hogander, Jouni Jan. 24, 2025, 11:39 a.m. UTC
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@intel.com>
---
 drivers/gpu/drm/i915/display/intel_display.c | 10 ++++++++++
 1 file changed, 10 insertions(+)
diff mbox series

Patch

diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
index 623ca5215ed44..6da46406576de 100644
--- a/drivers/gpu/drm/i915/display/intel_display.c
+++ b/drivers/gpu/drm/i915/display/intel_display.c
@@ -7685,6 +7685,7 @@  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;
@@ -7726,6 +7727,15 @@  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))