diff --git a/core/java/android/hardware/display/DisplayManagerGlobal.java b/core/java/android/hardware/display/DisplayManagerGlobal.java
index 4d645e6..0f9c708 100644
--- a/core/java/android/hardware/display/DisplayManagerGlobal.java
+++ b/core/java/android/hardware/display/DisplayManagerGlobal.java
@@ -34,7 +34,6 @@
 import android.os.Message;
 import android.os.RemoteException;
 import android.os.ServiceManager;
-import android.text.TextUtils;
 import android.util.Log;
 import android.util.Pair;
 import android.util.SparseArray;
@@ -74,6 +73,8 @@
     @UnsupportedAppUsage
     private static DisplayManagerGlobal sInstance;
 
+    // Guarded by mLock
+    private boolean mDispatchNativeCallbacks = false;
     private final Object mLock = new Object();
 
     @UnsupportedAppUsage
@@ -143,30 +144,38 @@
     @UnsupportedAppUsage
     public DisplayInfo getDisplayInfo(int displayId) {
         synchronized (mLock) {
-            DisplayInfo info = null;
-            if (mDisplayCache != null) {
-                info = mDisplayCache.query(displayId);
-            } else {
-                try {
-                    info = mDm.getDisplayInfo(displayId);
-                } catch (RemoteException ex) {
-                    ex.rethrowFromSystemServer();
-                }
-            }
-            if (info == null) {
-                return null;
-            }
-
-            registerCallbackIfNeededLocked();
-
-            if (DEBUG) {
-                Log.d(TAG, "getDisplayInfo: displayId=" + displayId + ", info=" + info);
-            }
-            return info;
+            return getDisplayInfoLocked(displayId);
         }
     }
 
     /**
+     * Gets information about a particular logical display
+     * See {@link getDisplayInfo}, but assumes that {@link mLock} is held
+     */
+    private @Nullable DisplayInfo getDisplayInfoLocked(int displayId) {
+        DisplayInfo info = null;
+        if (mDisplayCache != null) {
+            info = mDisplayCache.query(displayId);
+        } else {
+            try {
+                info = mDm.getDisplayInfo(displayId);
+            } catch (RemoteException ex) {
+                ex.rethrowFromSystemServer();
+            }
+        }
+        if (info == null) {
+            return null;
+        }
+
+        registerCallbackIfNeededLocked();
+
+        if (DEBUG) {
+            Log.d(TAG, "getDisplayInfo: displayId=" + displayId + ", info=" + info);
+        }
+        return info;
+    }
+
+    /**
      * Gets all currently valid logical display ids.
      *
      * @return An array containing all display ids.
@@ -341,6 +350,20 @@
             for (int i = 0; i < numListeners; i++) {
                 mDisplayListeners.get(i).sendDisplayEvent(displayId, event);
             }
+            if (event == EVENT_DISPLAY_CHANGED && mDispatchNativeCallbacks) {
+                // Choreographer only supports a single display, so only dispatch refresh rate
+                // changes for the default display.
+                if (displayId == Display.DEFAULT_DISPLAY) {
+                    // We can likely save a binder hop if we attach the refresh rate onto the
+                    // listener.
+                    DisplayInfo display = getDisplayInfoLocked(displayId);
+                    if (display != null) {
+                        float refreshRate = display.getMode().getRefreshRate();
+                        // Signal native callbacks if we ever set a refresh rate.
+                        nSignalNativeCallbacks(refreshRate);
+                    }
+                }
+            }
         }
     }
 
@@ -800,4 +823,30 @@
     public void disableLocalDisplayInfoCaches() {
         mDisplayCache = null;
     }
+
+    private static native void nSignalNativeCallbacks(float refreshRate);
+
+    // Called from AChoreographer via JNI.
+    // Registers AChoreographer so that refresh rate callbacks can be dispatched from DMS.
+    private void registerNativeChoreographerForRefreshRateCallbacks() {
+        synchronized (mLock) {
+            registerCallbackIfNeededLocked();
+            mDispatchNativeCallbacks = true;
+            DisplayInfo display = getDisplayInfoLocked(Display.DEFAULT_DISPLAY);
+            if (display != null) {
+                // We need to tell AChoreographer instances the current refresh rate so that apps
+                // can get it for free once a callback first registers.
+                float refreshRate = display.getMode().getRefreshRate();
+                nSignalNativeCallbacks(refreshRate);
+            }
+        }
+    }
+
+    // Called from AChoreographer via JNI.
+    // Unregisters AChoreographer from receiving refresh rate callbacks.
+    private void unregisterNativeChoreographerForRefreshRateCallbacks() {
+        synchronized (mLock) {
+            mDispatchNativeCallbacks = false;
+        }
+    }
 }
diff --git a/core/jni/Android.bp b/core/jni/Android.bp
index bd7bc4c..5a66f43 100644
--- a/core/jni/Android.bp
+++ b/core/jni/Android.bp
@@ -158,6 +158,7 @@
                 "android_hardware_camera2_legacy_LegacyCameraDevice.cpp",
                 "android_hardware_camera2_legacy_PerfMeasurement.cpp",
                 "android_hardware_camera2_DngCreator.cpp",
+                "android_hardware_display_DisplayManagerGlobal.cpp",
                 "android_hardware_display_DisplayViewport.cpp",
                 "android_hardware_HardwareBuffer.cpp",
                 "android_hardware_SensorManager.cpp",
diff --git a/core/jni/AndroidRuntime.cpp b/core/jni/AndroidRuntime.cpp
index 6fcaddf..a420ba6 100644
--- a/core/jni/AndroidRuntime.cpp
+++ b/core/jni/AndroidRuntime.cpp
@@ -18,39 +18,37 @@
 #define LOG_TAG "AndroidRuntime"
 #define LOG_NDEBUG 1
 
-#include <android_runtime/AndroidRuntime.h>
-
 #include <android-base/macros.h>
 #include <android-base/properties.h>
 #include <android/graphics/jni_runtime.h>
+#include <android_runtime/AndroidRuntime.h>
+#include <assert.h>
 #include <binder/IBinder.h>
 #include <binder/IPCThreadState.h>
 #include <binder/IServiceManager.h>
-#include <utils/Log.h>
-#include <utils/misc.h>
-#include <utils/Trace.h>
 #include <binder/Parcel.h>
-#include <utils/threads.h>
+#include <bionic/malloc.h>
 #include <cutils/properties.h>
-#include <server_configurable_flags/get_flags.h>
-
-#include "jni.h"
+#include <dirent.h>
+#include <dlfcn.h>
 #include <nativehelper/JNIHelp.h>
 #include <nativehelper/JniInvocation.h>
-#include "android_util_Binder.h"
-
-#include <stdio.h>
+#include <server_configurable_flags/get_flags.h>
 #include <signal.h>
+#include <stdio.h>
 #include <sys/stat.h>
 #include <sys/types.h>
-#include <signal.h>
-#include <dirent.h>
-#include <assert.h>
-#include <bionic/malloc.h>
+#include <utils/Log.h>
+#include <utils/Trace.h>
+#include <utils/misc.h>
+#include <utils/threads.h>
 
 #include <string>
 #include <vector>
 
+#include "android_util_Binder.h"
+#include "jni.h"
+
 using namespace android;
 using android::base::GetProperty;
 
@@ -78,6 +76,7 @@
 extern int register_android_hardware_camera2_legacy_LegacyCameraDevice(JNIEnv *env);
 extern int register_android_hardware_camera2_legacy_PerfMeasurement(JNIEnv *env);
 extern int register_android_hardware_camera2_DngCreator(JNIEnv *env);
+extern int register_android_hardware_display_DisplayManagerGlobal(JNIEnv* env);
 extern int register_android_hardware_HardwareBuffer(JNIEnv *env);
 extern int register_android_hardware_SensorManager(JNIEnv *env);
 extern int register_android_hardware_SerialPort(JNIEnv *env);
@@ -1519,6 +1518,7 @@
         REG_JNI(register_android_hardware_camera2_legacy_LegacyCameraDevice),
         REG_JNI(register_android_hardware_camera2_legacy_PerfMeasurement),
         REG_JNI(register_android_hardware_camera2_DngCreator),
+        REG_JNI(register_android_hardware_display_DisplayManagerGlobal),
         REG_JNI(register_android_hardware_HardwareBuffer),
         REG_JNI(register_android_hardware_SensorManager),
         REG_JNI(register_android_hardware_SerialPort),
diff --git a/core/jni/android_hardware_display_DisplayManagerGlobal.cpp b/core/jni/android_hardware_display_DisplayManagerGlobal.cpp
new file mode 100644
index 0000000..9f31671
--- /dev/null
+++ b/core/jni/android_hardware_display_DisplayManagerGlobal.cpp
@@ -0,0 +1,55 @@
+/*
+ * Copyright 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "DisplayManagerGlobal-JNI"
+
+#include <nativehelper/JNIHelp.h>
+#include <nativehelper/ScopedUtfChars.h>
+#include <private/android/choreographer.h>
+
+#include <vector>
+
+#include "core_jni_helpers.h"
+
+using namespace android;
+
+namespace android {
+
+// Dispatches the current refresh rate for the default display to all
+// choreographer instances
+void android_hardware_display_DisplayManagerGlobal_signalNativeCallbacks(JNIEnv* env, jobject,
+                                                                         jfloat refreshRate) {
+    const constexpr int64_t kNanosPerSecond = 1000 * 1000 * 1000;
+    const nsecs_t vsyncPeriod = kNanosPerSecond / refreshRate;
+
+    AChoreographer_signalRefreshRateCallbacks(vsyncPeriod);
+}
+
+} // namespace android
+
+// ----------------------------------------------------------------------------
+
+const char* const kClassPathName = "android/hardware/display/DisplayManagerGlobal";
+
+static const JNINativeMethod gMethods[] = {
+        {"nSignalNativeCallbacks", "(F)V",
+         (void*)android_hardware_display_DisplayManagerGlobal_signalNativeCallbacks},
+};
+
+int register_android_hardware_display_DisplayManagerGlobal(JNIEnv* env) {
+    AChoreographer_initJVM(env);
+    return RegisterMethodsOrDie(env, kClassPathName, gMethods, NELEM(gMethods));
+}
diff --git a/core/jni/include/android_runtime/AndroidRuntime.h b/core/jni/include/android_runtime/AndroidRuntime.h
index 2351272..d86d934 100644
--- a/core/jni/include/android_runtime/AndroidRuntime.h
+++ b/core/jni/include/android_runtime/AndroidRuntime.h
@@ -19,15 +19,14 @@
 #ifndef _RUNTIME_ANDROID_RUNTIME_H
 #define _RUNTIME_ANDROID_RUNTIME_H
 
-#include <utils/Errors.h>
 #include <binder/IBinder.h>
-#include <utils/String8.h>
+#include <jni.h>
+#include <pthread.h>
+#include <utils/Errors.h>
 #include <utils/String16.h>
+#include <utils/String8.h>
 #include <utils/Vector.h>
 #include <utils/threads.h>
-#include <pthread.h>
-#include <jni.h>
-
 
 namespace android {
 
@@ -154,6 +153,6 @@
     static int javaThreadShell(void* args);
 };
 
-}
+} // namespace android
 
 #endif
diff --git a/native/android/Android.bp b/native/android/Android.bp
index ed73f39..797d3fd 100644
--- a/native/android/Android.bp
+++ b/native/android/Android.bp
@@ -37,6 +37,7 @@
 
     srcs: [
         "asset_manager.cpp",
+        "choreographer.cpp",
         "configuration.cpp",
         "hardware_buffer_jni.cpp",
         "input.cpp",
@@ -49,6 +50,7 @@
         "sharedmem.cpp",
         "storage_manager.cpp",
         "surface_control.cpp",
+        "surface_texture.cpp",
         "system_fonts.cpp",
         "trace.cpp",
         "thermal.cpp"
@@ -76,6 +78,7 @@
         "libpowermanager",
         "android.hardware.configstore@1.0",
         "android.hardware.configstore-utils",
+        "libnativedisplay",
     ],
 
     static_libs: [
@@ -83,9 +86,9 @@
         "libarect",
     ],
 
-    header_libs: [ "libhwui_internal_headers" ],
+    header_libs: [ "libhwui_internal_headers",],
 
-    whole_static_libs: ["libnativedisplay", "libnativewindow"],
+    whole_static_libs: ["libnativewindow"],
 
     export_static_lib_headers: ["libarect"],
 
diff --git a/native/android/choreographer.cpp b/native/android/choreographer.cpp
new file mode 100644
index 0000000..38641de
--- /dev/null
+++ b/native/android/choreographer.cpp
@@ -0,0 +1,52 @@
+/*
+ * Copyright 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <private/android/choreographer.h>
+
+using namespace android;
+
+AChoreographer* AChoreographer_getInstance() {
+    return AChoreographer_routeGetInstance();
+}
+void AChoreographer_postFrameCallback(AChoreographer* choreographer,
+                                      AChoreographer_frameCallback callback, void* data) {
+    return AChoreographer_routePostFrameCallback(choreographer, callback, data);
+}
+void AChoreographer_postFrameCallbackDelayed(AChoreographer* choreographer,
+                                             AChoreographer_frameCallback callback, void* data,
+                                             long delayMillis) {
+    return AChoreographer_routePostFrameCallbackDelayed(choreographer, callback, data, delayMillis);
+}
+void AChoreographer_postFrameCallback64(AChoreographer* choreographer,
+                                        AChoreographer_frameCallback64 callback, void* data) {
+    return AChoreographer_routePostFrameCallback64(choreographer, callback, data);
+}
+void AChoreographer_postFrameCallbackDelayed64(AChoreographer* choreographer,
+                                               AChoreographer_frameCallback64 callback, void* data,
+                                               uint32_t delayMillis) {
+    return AChoreographer_routePostFrameCallbackDelayed64(choreographer, callback, data,
+                                                          delayMillis);
+}
+void AChoreographer_registerRefreshRateCallback(AChoreographer* choreographer,
+                                                AChoreographer_refreshRateCallback callback,
+                                                void* data) {
+    return AChoreographer_routeRegisterRefreshRateCallback(choreographer, callback, data);
+}
+void AChoreographer_unregisterRefreshRateCallback(AChoreographer* choreographer,
+                                                  AChoreographer_refreshRateCallback callback,
+                                                  void* data) {
+    return AChoreographer_routeUnregisterRefreshRateCallback(choreographer, callback, data);
+}
diff --git a/native/android/surface_texture.cpp b/native/android/surface_texture.cpp
new file mode 100644
index 0000000..ff35204
--- /dev/null
+++ b/native/android/surface_texture.cpp
@@ -0,0 +1,52 @@
+/*
+ * Copyright 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <android/surface_texture_jni.h>
+#include <surfacetexture/surface_texture_platform.h>
+
+using namespace android;
+
+ANativeWindow* ASurfaceTexture_acquireANativeWindow(ASurfaceTexture* st) {
+    return ASurfaceTexture_routeAcquireANativeWindow(st);
+}
+
+int ASurfaceTexture_attachToGLContext(ASurfaceTexture* st, uint32_t texName) {
+    return ASurfaceTexture_routeAttachToGLContext(st, texName);
+}
+
+int ASurfaceTexture_detachFromGLContext(ASurfaceTexture* st) {
+    return ASurfaceTexture_routeDetachFromGLContext(st);
+}
+
+void ASurfaceTexture_release(ASurfaceTexture* st) {
+    return ASurfaceTexture_routeRelease(st);
+}
+
+int ASurfaceTexture_updateTexImage(ASurfaceTexture* st) {
+    return ASurfaceTexture_routeUpdateTexImage(st);
+}
+
+void ASurfaceTexture_getTransformMatrix(ASurfaceTexture* st, float mtx[16]) {
+    return ASurfaceTexture_routeGetTransformMatrix(st, mtx);
+}
+
+int64_t ASurfaceTexture_getTimestamp(ASurfaceTexture* st) {
+    return ASurfaceTexture_routeGetTimestamp(st);
+}
+
+ASurfaceTexture* ASurfaceTexture_fromSurfaceTexture(JNIEnv* env, jobject surfacetexture) {
+    return ASurfaceTexture_routeFromSurfaceTexture(env, surfacetexture);
+}