drm/i915/psr: Reject async flips when selective fetch is enabled

The selective fetch code doesn't handle asycn flips correctly.
There is a nonsense check for async flips in
intel_psr2_sel_fetch_config_valid() but that only gets called
for modesets/fastsets and thus does nothing for async flips.

Currently intel_async_flip_check_hw() is very unhappy as the
selective fetch code pulls in planes that are not even async
flips capable.

Reject async flips when selective fetch is enabled, until
someone fixes this properly (ie. disable selective fetch while
async flips are being issued).

Cc: stable@vger.kernel.org
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patch.msgid.link/20251105171015.22234-1-ville.syrjala@linux.intel.com
Reviewed-by: Jouni Högander <jouni.hogander@intel.com>
(cherry picked from commit a5f0cc8)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

Author: vsyrjala

drivers/gpu/drm/i915/display/intel_display.c

@@ -5964,6 +5964,14 @@ static int intel_async_flip_check_uapi(struct intel_atomic_state *state,
 		return -EINVAL;
 	}
 
+	/* FIXME: selective fetch should be disabled for async flips */
+	if (new_crtc_state->enable_psr2_sel_fetch) {
+		drm_dbg_kms(display->drm,
+			    "[CRTC:%d:%s] async flip disallowed with PSR2 selective fetch\n",
+			    crtc->base.base.id, crtc->base.name);
+		return -EINVAL;
+	}
+
 	for_each_oldnew_intel_plane_in_state(state, plane, old_plane_state,
 					     new_plane_state, i) {
 		if (plane->pipe != crtc->pipe)

drivers/gpu/drm/i915/display/intel_psr.c

@@ -1256,12 +1256,6 @@ static bool intel_psr2_sel_fetch_config_valid(struct intel_dp *intel_dp,
 		return false;
 	}
 
-	if (crtc_state->uapi.async_flip) {
-		drm_dbg_kms(display->drm,
-			    "PSR2 sel fetch not enabled, async flip enabled\n");
-		return false;
-	}
-
 	return crtc_state->enable_psr2_sel_fetch = true;
 }