drm/amd/display: allow self-refresh exit while entry is blocked

amdgpu_dm_crtc_set_static_screen_optimze() maps sso_enable to the
Replay and PSR1 vsync events. allow_sr_entry is an entry gate, but the
helper currently applies it to both directions.

A non-fast update clears allow_sr_entry. During a modeset, a separate
hardware-programming event keeps self-refresh blocked while the stream
is reprogrammed. If vblank is enabled before the entry delay expires,
the ISM calls the helper with sso_enable false. The early return drops
the disable request, so the vsync events are not set.

After enough fast commits, allow_sr_entry becomes true and the
hardware-programming event can be cleared. Since the vblank reference
remains held, there is no further zero-to-one vblank transition to
restore the missing vsync events. Replay or PSR1 can then become active
while vblank is still enabled.

Gate only requests that enable static-screen optimization. Always
process disable requests so a vblank requestor keeps Replay and PSR1
blocked.

On a Phoenix system, repeated SDDM-to-VT handoffs produced stuck flips
followed by flip_done and commit-wait timeouts. The timeout was not
observed with this change applied.

Fixes: 3c108046e1 ("drm/amd/display: Add power module on Linux")
Assisted-by: Codex:gpt-5.6-sol
Assisted-by: Claude:opus-5
Signed-off-by: David Weber <weber.aulendorf@gmail.com>
Reviewed-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crtc.c

@@ -125,7 +125,11 @@ void amdgpu_dm_crtc_set_static_screen_optimze(
 	struct dc_link *link = stream->link;
 	bool set_vsync_event = !sso_enable;
 
-	if (!allow_sr_entry)
+	/*
+	 * allow_sr_entry gates only entry. A disable request must still set
+	 * the vsync events to force Replay and PSR1 out and keep them blocked.
+	 */
+	if (sso_enable && !allow_sr_entry)
 		return;
 
 	amdgpu_dm_replay_set_event(dm, stream,