diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index aab8331..04fee50 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -637,6 +637,17 @@
     return displayIds;
 }
 
+status_t SurfaceFlinger::getPrimaryPhysicalDisplayId(PhysicalDisplayId* id) const {
+    Mutex::Autolock lock(mStateLock);
+    const auto display = getInternalDisplayIdLocked();
+    if (!display) {
+        return NAME_NOT_FOUND;
+    }
+
+    *id = *display;
+    return NO_ERROR;
+}
+
 sp<IBinder> SurfaceFlinger::getPhysicalDisplayToken(PhysicalDisplayId displayId) const {
     Mutex::Autolock lock(mStateLock);
     return getPhysicalDisplayTokenLocked(displayId);
@@ -5242,6 +5253,7 @@
         case REMOVE_TUNNEL_MODE_ENABLED_LISTENER:
         case NOTIFY_POWER_BOOST:
         case SET_GLOBAL_SHADOW_SETTINGS:
+        case GET_PRIMARY_PHYSICAL_DISPLAY_ID:
         case ACQUIRE_FRAME_RATE_FLEXIBILITY_TOKEN: {
             // ACQUIRE_FRAME_RATE_FLEXIBILITY_TOKEN and OVERRIDE_HDR_TYPES are used by CTS tests,
             // which acquire the necessary permission dynamically. Don't use the permission cache