diff --git a/services/surfaceflinger/BufferLayer.cpp b/services/surfaceflinger/BufferLayer.cpp
index 861d496..490775f 100644
--- a/services/surfaceflinger/BufferLayer.cpp
+++ b/services/surfaceflinger/BufferLayer.cpp
@@ -401,12 +401,13 @@
         const Fps refreshRate = display->refreshRateConfigs().getCurrentRefreshRate().getFps();
         const std::optional<Fps> renderRate =
                 mFlinger->mScheduler->getFrameRateOverride(getOwnerUid());
+
+        const auto vote = frameRateToSetFrameRateVotePayload(mDrawingState.frameRate);
+        const auto gameMode = getGameMode();
+
         if (presentFence->isValid()) {
             mFlinger->mTimeStats->setPresentFence(layerId, mCurrentFrameNumber, presentFence,
-                                                  refreshRate, renderRate,
-                                                  frameRateToSetFrameRateVotePayload(
-                                                          mDrawingState.frameRate),
-                                                  getGameMode());
+                                                  refreshRate, renderRate, vote, gameMode);
             mFlinger->mFrameTracer->traceFence(layerId, getCurrentBufferId(), mCurrentFrameNumber,
                                                presentFence,
                                                FrameTracer::FrameEvent::PRESENT_FENCE);
@@ -417,10 +418,7 @@
             // timestamp instead.
             const nsecs_t actualPresentTime = display->getRefreshTimestamp();
             mFlinger->mTimeStats->setPresentTime(layerId, mCurrentFrameNumber, actualPresentTime,
-                                                 refreshRate, renderRate,
-                                                 frameRateToSetFrameRateVotePayload(
-                                                         mDrawingState.frameRate),
-                                                 getGameMode());
+                                                 refreshRate, renderRate, vote, gameMode);
             mFlinger->mFrameTracer->traceTimestamp(layerId, getCurrentBufferId(),
                                                    mCurrentFrameNumber, actualPresentTime,
                                                    FrameTracer::FrameEvent::PRESENT_FENCE);
diff --git a/services/surfaceflinger/CompositionEngine/include/compositionengine/DisplaySurface.h b/services/surfaceflinger/CompositionEngine/include/compositionengine/DisplaySurface.h
index 4502eee..c553fce 100644
--- a/services/surfaceflinger/CompositionEngine/include/compositionengine/DisplaySurface.h
+++ b/services/surfaceflinger/CompositionEngine/include/compositionengine/DisplaySurface.h
@@ -16,6 +16,8 @@
 
 #pragma once
 
+#include <cinttypes>
+
 #include <ui/Size.h>
 #include <utils/Errors.h>
 #include <utils/RefBase.h>
@@ -47,13 +49,8 @@
     // before composition takes place. The DisplaySurface can use the
     // composition type to decide how to manage the flow of buffers between
     // GPU and HWC for this frame.
-    enum CompositionType {
-        COMPOSITION_UNKNOWN = 0,
-        COMPOSITION_GPU = 1,
-        COMPOSITION_HWC = 2,
-        COMPOSITION_MIXED = COMPOSITION_GPU | COMPOSITION_HWC
-    };
-    virtual status_t prepareFrame(CompositionType compositionType) = 0;
+    enum class CompositionType : uint8_t { Unknown = 0, Gpu = 0b1, Hwc = 0b10, Mixed = Gpu | Hwc };
+    virtual status_t prepareFrame(CompositionType) = 0;
 
     // Inform the surface that GPU composition is complete for this frame, and
     // the surface should make sure that HWComposer has the correct buffer for
diff --git a/services/surfaceflinger/CompositionEngine/src/RenderSurface.cpp b/services/surfaceflinger/CompositionEngine/src/RenderSurface.cpp
index ef50870..a19d23f 100644
--- a/services/surfaceflinger/CompositionEngine/src/RenderSurface.cpp
+++ b/services/surfaceflinger/CompositionEngine/src/RenderSurface.cpp
@@ -127,19 +127,18 @@
 }
 
 void RenderSurface::prepareFrame(bool usesClientComposition, bool usesDeviceComposition) {
-    DisplaySurface::CompositionType compositionType;
-    if (usesClientComposition && usesDeviceComposition) {
-        compositionType = DisplaySurface::COMPOSITION_MIXED;
-    } else if (usesClientComposition) {
-        compositionType = DisplaySurface::COMPOSITION_GPU;
-    } else if (usesDeviceComposition) {
-        compositionType = DisplaySurface::COMPOSITION_HWC;
-    } else {
+    const auto compositionType = [=] {
+        using CompositionType = DisplaySurface::CompositionType;
+
+        if (usesClientComposition && usesDeviceComposition) return CompositionType::Mixed;
+        if (usesClientComposition) return CompositionType::Gpu;
+        if (usesDeviceComposition) return CompositionType::Hwc;
+
         // Nothing to do -- when turning the screen off we get a frame like
         // this. Call it a HWC frame since we won't be doing any GPU work but
         // will do a prepare/set cycle.
-        compositionType = DisplaySurface::COMPOSITION_HWC;
-    }
+        return CompositionType::Hwc;
+    }();
 
     if (status_t result = mDisplaySurface->prepareFrame(compositionType); result != NO_ERROR) {
         ALOGE("updateCompositionType failed for %s: %d (%s)", mDisplay.getName().c_str(), result,
diff --git a/services/surfaceflinger/CompositionEngine/tests/RenderSurfaceTest.cpp b/services/surfaceflinger/CompositionEngine/tests/RenderSurfaceTest.cpp
index 431cc93..7c8e41b 100644
--- a/services/surfaceflinger/CompositionEngine/tests/RenderSurfaceTest.cpp
+++ b/services/surfaceflinger/CompositionEngine/tests/RenderSurfaceTest.cpp
@@ -201,28 +201,28 @@
  */
 
 TEST_F(RenderSurfaceTest, prepareFrameHandlesMixedComposition) {
-    EXPECT_CALL(*mDisplaySurface, prepareFrame(DisplaySurface::COMPOSITION_MIXED))
+    EXPECT_CALL(*mDisplaySurface, prepareFrame(DisplaySurface::CompositionType::Mixed))
             .WillOnce(Return(NO_ERROR));
 
     mSurface.prepareFrame(true, true);
 }
 
 TEST_F(RenderSurfaceTest, prepareFrameHandlesOnlyGpuComposition) {
-    EXPECT_CALL(*mDisplaySurface, prepareFrame(DisplaySurface::COMPOSITION_GPU))
+    EXPECT_CALL(*mDisplaySurface, prepareFrame(DisplaySurface::CompositionType::Gpu))
             .WillOnce(Return(NO_ERROR));
 
     mSurface.prepareFrame(true, false);
 }
 
 TEST_F(RenderSurfaceTest, prepareFrameHandlesOnlyHwcComposition) {
-    EXPECT_CALL(*mDisplaySurface, prepareFrame(DisplaySurface::COMPOSITION_HWC))
+    EXPECT_CALL(*mDisplaySurface, prepareFrame(DisplaySurface::CompositionType::Hwc))
             .WillOnce(Return(NO_ERROR));
 
     mSurface.prepareFrame(false, true);
 }
 
 TEST_F(RenderSurfaceTest, prepareFrameHandlesNoComposition) {
-    EXPECT_CALL(*mDisplaySurface, prepareFrame(DisplaySurface::COMPOSITION_HWC))
+    EXPECT_CALL(*mDisplaySurface, prepareFrame(DisplaySurface::CompositionType::Hwc))
             .WillOnce(Return(NO_ERROR));
 
     mSurface.prepareFrame(false, false);
diff --git a/services/surfaceflinger/DisplayHardware/VirtualDisplaySurface.cpp b/services/surfaceflinger/DisplayHardware/VirtualDisplaySurface.cpp
index 82a9ae2..b4fb51f 100644
--- a/services/surfaceflinger/DisplayHardware/VirtualDisplaySurface.cpp
+++ b/services/surfaceflinger/DisplayHardware/VirtualDisplaySurface.cpp
@@ -21,20 +21,18 @@
 // #define LOG_NDEBUG 0
 #include "VirtualDisplaySurface.h"
 
-#include <inttypes.h>
+#include <cinttypes>
 
 #include "HWComposer.h"
 #include "SurfaceFlinger.h"
 
+#include <ftl/Flags.h>
+#include <ftl/enum.h>
 #include <gui/BufferItem.h>
 #include <gui/BufferQueue.h>
 #include <gui/IProducerListener.h>
 #include <system/window.h>
 
-// ---------------------------------------------------------------------------
-namespace android {
-// ---------------------------------------------------------------------------
-
 #define VDS_LOGE(msg, ...) ALOGE("[%s] " msg, \
         mDisplayName.c_str(), ##__VA_ARGS__)
 #define VDS_LOGW_IF(cond, msg, ...) ALOGW_IF(cond, "[%s] " msg, \
@@ -42,20 +40,11 @@
 #define VDS_LOGV(msg, ...) ALOGV("[%s] " msg, \
         mDisplayName.c_str(), ##__VA_ARGS__)
 
-static const char* dbgCompositionTypeStr(compositionengine::DisplaySurface::CompositionType type) {
-    switch (type) {
-        case compositionengine::DisplaySurface::COMPOSITION_UNKNOWN:
-            return "UNKNOWN";
-        case compositionengine::DisplaySurface::COMPOSITION_GPU:
-            return "GPU";
-        case compositionengine::DisplaySurface::COMPOSITION_HWC:
-            return "HWC";
-        case compositionengine::DisplaySurface::COMPOSITION_MIXED:
-            return "MIXED";
-        default:
-            return "<INVALID>";
-    }
-}
+#define UNSUPPORTED()                                               \
+    VDS_LOGE("%s: Invalid operation on virtual display", __func__); \
+    return INVALID_OPERATION
+
+namespace android {
 
 VirtualDisplaySurface::VirtualDisplaySurface(HWComposer& hwc, VirtualDisplayId displayId,
                                              const sp<IGraphicBufferProducer>& sink,
@@ -76,14 +65,10 @@
         mQueueBufferOutput(),
         mSinkBufferWidth(0),
         mSinkBufferHeight(0),
-        mCompositionType(COMPOSITION_UNKNOWN),
         mFbFence(Fence::NO_FENCE),
         mOutputFence(Fence::NO_FENCE),
         mFbProducerSlot(BufferQueue::INVALID_BUFFER_SLOT),
         mOutputProducerSlot(BufferQueue::INVALID_BUFFER_SLOT),
-        mDbgState(DBG_STATE_IDLE),
-        mDbgLastCompositionType(COMPOSITION_UNKNOWN),
-        mMustRecompose(false),
         mForceHwcCopy(SurfaceFlinger::useHwcForRgbToYuv) {
     mSource[SOURCE_SINK] = sink;
     mSource[SOURCE_SCRATCH] = bqProducer;
@@ -131,9 +116,9 @@
 
     mMustRecompose = mustRecompose;
 
-    VDS_LOGW_IF(mDbgState != DBG_STATE_IDLE,
-            "Unexpected beginFrame() in %s state", dbgStateStr());
-    mDbgState = DBG_STATE_BEGUN;
+    VDS_LOGW_IF(mDebugState != DebugState::Idle, "Unexpected %s in %s state", __func__,
+                ftl::enum_string(mDebugState).c_str());
+    mDebugState = DebugState::Begun;
 
     return refreshOutputBuffer();
 }
@@ -143,12 +128,12 @@
         return NO_ERROR;
     }
 
-    VDS_LOGW_IF(mDbgState != DBG_STATE_BEGUN,
-            "Unexpected prepareFrame() in %s state", dbgStateStr());
-    mDbgState = DBG_STATE_PREPARED;
+    VDS_LOGW_IF(mDebugState != DebugState::Begun, "Unexpected %s in %s state", __func__,
+                ftl::enum_string(mDebugState).c_str());
+    mDebugState = DebugState::Prepared;
 
     mCompositionType = compositionType;
-    if (mForceHwcCopy && mCompositionType == COMPOSITION_GPU) {
+    if (mForceHwcCopy && mCompositionType == CompositionType::Gpu) {
         // Some hardware can do RGB->YUV conversion more efficiently in hardware
         // controlled by HWC than in hardware controlled by the video encoder.
         // Forcing GPU-composed frames to go through an extra copy by the HWC
@@ -157,16 +142,16 @@
         //
         // On the other hand, when the consumer prefers RGB or can consume RGB
         // inexpensively, this forces an unnecessary copy.
-        mCompositionType = COMPOSITION_MIXED;
+        mCompositionType = CompositionType::Mixed;
     }
 
-    if (mCompositionType != mDbgLastCompositionType) {
-        VDS_LOGV("prepareFrame: composition type changed to %s",
-                dbgCompositionTypeStr(mCompositionType));
-        mDbgLastCompositionType = mCompositionType;
+    if (mCompositionType != mDebugLastCompositionType) {
+        VDS_LOGV("%s: composition type changed to %s", __func__,
+                 toString(mCompositionType).c_str());
+        mDebugLastCompositionType = mCompositionType;
     }
 
-    if (mCompositionType != COMPOSITION_GPU &&
+    if (mCompositionType != CompositionType::Gpu &&
         (mOutputFormat != mDefaultOutputFormat || mOutputUsage != GRALLOC_USAGE_HW_COMPOSER)) {
         // We must have just switched from GPU-only to MIXED or HWC
         // composition. Stop using the format and usage requested by the GPU
@@ -191,33 +176,32 @@
         return NO_ERROR;
     }
 
-    if (mCompositionType == COMPOSITION_HWC) {
-        VDS_LOGW_IF(mDbgState != DBG_STATE_PREPARED,
-                "Unexpected advanceFrame() in %s state on HWC frame",
-                dbgStateStr());
+    if (mCompositionType == CompositionType::Hwc) {
+        VDS_LOGW_IF(mDebugState != DebugState::Prepared, "Unexpected %s in %s state on HWC frame",
+                    __func__, ftl::enum_string(mDebugState).c_str());
     } else {
-        VDS_LOGW_IF(mDbgState != DBG_STATE_GPU_DONE,
-                    "Unexpected advanceFrame() in %s state on GPU/MIXED frame", dbgStateStr());
+        VDS_LOGW_IF(mDebugState != DebugState::GpuDone,
+                    "Unexpected %s in %s state on GPU/MIXED frame", __func__,
+                    ftl::enum_string(mDebugState).c_str());
     }
-    mDbgState = DBG_STATE_HWC;
+    mDebugState = DebugState::Hwc;
 
     if (mOutputProducerSlot < 0 ||
-            (mCompositionType != COMPOSITION_HWC && mFbProducerSlot < 0)) {
+        (mCompositionType != CompositionType::Hwc && mFbProducerSlot < 0)) {
         // Last chance bailout if something bad happened earlier. For example,
         // in a graphics API configuration, if the sink disappears then dequeueBuffer
         // will fail, the GPU driver won't queue a buffer, but SurfaceFlinger
         // will soldier on. So we end up here without a buffer. There should
         // be lots of scary messages in the log just before this.
-        VDS_LOGE("advanceFrame: no buffer, bailing out");
+        VDS_LOGE("%s: no buffer, bailing out", __func__);
         return NO_MEMORY;
     }
 
     sp<GraphicBuffer> fbBuffer = mFbProducerSlot >= 0 ?
             mProducerBuffers[mFbProducerSlot] : sp<GraphicBuffer>(nullptr);
     sp<GraphicBuffer> outBuffer = mProducerBuffers[mOutputProducerSlot];
-    VDS_LOGV("advanceFrame: fb=%d(%p) out=%d(%p)",
-            mFbProducerSlot, fbBuffer.get(),
-            mOutputProducerSlot, outBuffer.get());
+    VDS_LOGV("%s: fb=%d(%p) out=%d(%p)", __func__, mFbProducerSlot, fbBuffer.get(),
+             mOutputProducerSlot, outBuffer.get());
 
     const auto halDisplayId = HalVirtualDisplayId::tryCast(mDisplayId);
     LOG_FATAL_IF(!halDisplayId);
@@ -245,16 +229,16 @@
         return;
     }
 
-    VDS_LOGW_IF(mDbgState != DBG_STATE_HWC,
-            "Unexpected onFrameCommitted() in %s state", dbgStateStr());
-    mDbgState = DBG_STATE_IDLE;
+    VDS_LOGW_IF(mDebugState != DebugState::Hwc, "Unexpected %s in %s state", __func__,
+                ftl::enum_string(mDebugState).c_str());
+    mDebugState = DebugState::Idle;
 
     sp<Fence> retireFence = mHwc.getPresentFence(*halDisplayId);
-    if (mCompositionType == COMPOSITION_MIXED && mFbProducerSlot >= 0) {
+    if (mCompositionType == CompositionType::Mixed && mFbProducerSlot >= 0) {
         // release the scratch buffer back to the pool
         Mutex::Autolock lock(mMutex);
         int sslot = mapProducer2SourceSlot(SOURCE_SCRATCH, mFbProducerSlot);
-        VDS_LOGV("onFrameCommitted: release scratch sslot=%d", sslot);
+        VDS_LOGV("%s: release scratch sslot=%d", __func__, sslot);
         addReleaseFenceLocked(sslot, mProducerBuffers[mFbProducerSlot],
                 retireFence);
         releaseBufferLocked(sslot, mProducerBuffers[mFbProducerSlot]);
@@ -263,7 +247,7 @@
     if (mOutputProducerSlot >= 0) {
         int sslot = mapProducer2SourceSlot(SOURCE_SINK, mOutputProducerSlot);
         QueueBufferOutput qbo;
-        VDS_LOGV("onFrameCommitted: queue sink sslot=%d", sslot);
+        VDS_LOGV("%s: queue sink sslot=%d", __func__, sslot);
         if (mMustRecompose) {
             status_t result = mSource[SOURCE_SINK]->queueBuffer(sslot,
                     QueueBufferInput(
@@ -308,8 +292,8 @@
         return mSource[SOURCE_SINK]->requestBuffer(pslot, outBuf);
     }
 
-    VDS_LOGW_IF(mDbgState != DBG_STATE_GPU, "Unexpected requestBuffer pslot=%d in %s state", pslot,
-                dbgStateStr());
+    VDS_LOGW_IF(mDebugState != DebugState::Gpu, "Unexpected %s pslot=%d in %s state", __func__,
+                pslot, ftl::enum_string(mDebugState).c_str());
 
     *outBuf = mProducerBuffers[pslot];
     return NO_ERROR;
@@ -334,8 +318,8 @@
     if (result < 0)
         return result;
     int pslot = mapSource2ProducerSlot(source, *sslot);
-    VDS_LOGV("dequeueBuffer(%s): sslot=%d pslot=%d result=%d",
-            dbgSourceStr(source), *sslot, pslot, result);
+    VDS_LOGV("%s(%s): sslot=%d pslot=%d result=%d", __func__, ftl::enum_string(source).c_str(),
+             *sslot, pslot, result);
     uint64_t sourceBit = static_cast<uint64_t>(source) << pslot;
 
     // reset producer slot reallocation flag
@@ -363,10 +347,9 @@
             mSource[source]->cancelBuffer(*sslot, *fence);
             return result;
         }
-        VDS_LOGV("dequeueBuffer(%s): buffers[%d]=%p fmt=%d usage=%#" PRIx64,
-                dbgSourceStr(source), pslot, mProducerBuffers[pslot].get(),
-                mProducerBuffers[pslot]->getPixelFormat(),
-                mProducerBuffers[pslot]->getUsage());
+        VDS_LOGV("%s(%s): buffers[%d]=%p fmt=%d usage=%#" PRIx64, __func__,
+                 ftl::enum_string(source).c_str(), pslot, mProducerBuffers[pslot].get(),
+                 mProducerBuffers[pslot]->getPixelFormat(), mProducerBuffers[pslot]->getUsage());
 
         // propagate reallocation to VDS consumer
         mProducerSlotNeedReallocation |= 1ULL << pslot;
@@ -384,11 +367,11 @@
                                                    outTimestamps);
     }
 
-    VDS_LOGW_IF(mDbgState != DBG_STATE_PREPARED,
-            "Unexpected dequeueBuffer() in %s state", dbgStateStr());
-    mDbgState = DBG_STATE_GPU;
+    VDS_LOGW_IF(mDebugState != DebugState::Prepared, "Unexpected %s in %s state", __func__,
+                ftl::enum_string(mDebugState).c_str());
+    mDebugState = DebugState::Gpu;
 
-    VDS_LOGV("dequeueBuffer %dx%d fmt=%d usage=%#" PRIx64, w, h, format, usage);
+    VDS_LOGV("%s %dx%d fmt=%d usage=%#" PRIx64, __func__, w, h, format, usage);
 
     status_t result = NO_ERROR;
     Source source = fbSourceForCompositionType(mCompositionType);
@@ -401,7 +384,7 @@
             // will fail, the GPU driver won't queue a buffer, but SurfaceFlinger
             // will soldier on. So we end up here without a buffer. There should
             // be lots of scary messages in the log just before this.
-            VDS_LOGE("dequeueBuffer: no buffer, bailing out");
+            VDS_LOGE("%s: no buffer, bailing out", __func__);
             return NO_MEMORY;
         }
 
@@ -417,12 +400,11 @@
                 (format != 0 && format != buf->getPixelFormat()) ||
                 (w != 0 && w != mSinkBufferWidth) ||
                 (h != 0 && h != mSinkBufferHeight)) {
-            VDS_LOGV("dequeueBuffer: dequeueing new output buffer: "
-                    "want %dx%d fmt=%d use=%#" PRIx64 ", "
-                    "have %dx%d fmt=%d use=%#" PRIx64,
-                    w, h, format, usage,
-                    mSinkBufferWidth, mSinkBufferHeight,
-                    buf->getPixelFormat(), buf->getUsage());
+            VDS_LOGV("%s: dequeueing new output buffer: "
+                     "want %dx%d fmt=%d use=%#" PRIx64 ", "
+                     "have %dx%d fmt=%d use=%#" PRIx64,
+                     __func__, w, h, format, usage, mSinkBufferWidth, mSinkBufferHeight,
+                     buf->getPixelFormat(), buf->getUsage());
             mOutputFormat = format;
             mOutputUsage = usage;
             result = refreshOutputBuffer();
@@ -452,21 +434,16 @@
     return result;
 }
 
-status_t VirtualDisplaySurface::detachBuffer(int /* slot */) {
-    VDS_LOGE("detachBuffer is not available for VirtualDisplaySurface");
-    return INVALID_OPERATION;
+status_t VirtualDisplaySurface::detachBuffer(int) {
+    UNSUPPORTED();
 }
 
-status_t VirtualDisplaySurface::detachNextBuffer(
-        sp<GraphicBuffer>* /* outBuffer */, sp<Fence>* /* outFence */) {
-    VDS_LOGE("detachNextBuffer is not available for VirtualDisplaySurface");
-    return INVALID_OPERATION;
+status_t VirtualDisplaySurface::detachNextBuffer(sp<GraphicBuffer>*, sp<Fence>*) {
+    UNSUPPORTED();
 }
 
-status_t VirtualDisplaySurface::attachBuffer(int* /* outSlot */,
-        const sp<GraphicBuffer>& /* buffer */) {
-    VDS_LOGE("attachBuffer is not available for VirtualDisplaySurface");
-    return INVALID_OPERATION;
+status_t VirtualDisplaySurface::attachBuffer(int*, const sp<GraphicBuffer>&) {
+    UNSUPPORTED();
 }
 
 status_t VirtualDisplaySurface::queueBuffer(int pslot,
@@ -475,14 +452,14 @@
         return mSource[SOURCE_SINK]->queueBuffer(pslot, input, output);
     }
 
-    VDS_LOGW_IF(mDbgState != DBG_STATE_GPU, "Unexpected queueBuffer(pslot=%d) in %s state", pslot,
-                dbgStateStr());
-    mDbgState = DBG_STATE_GPU_DONE;
+    VDS_LOGW_IF(mDebugState != DebugState::Gpu, "Unexpected %s(pslot=%d) in %s state", __func__,
+                pslot, ftl::enum_string(mDebugState).c_str());
+    mDebugState = DebugState::GpuDone;
 
-    VDS_LOGV("queueBuffer pslot=%d", pslot);
+    VDS_LOGV("%s pslot=%d", __func__, pslot);
 
     status_t result;
-    if (mCompositionType == COMPOSITION_MIXED) {
+    if (mCompositionType == CompositionType::Mixed) {
         // Queue the buffer back into the scratch pool
         QueueBufferOutput scratchQBO;
         int sslot = mapProducer2SourceSlot(SOURCE_SCRATCH, pslot);
@@ -498,15 +475,15 @@
         if (result != NO_ERROR)
             return result;
         VDS_LOGW_IF(item.mSlot != sslot,
-                "queueBuffer: acquired sslot %d from SCRATCH after queueing sslot %d",
-                item.mSlot, sslot);
+                    "%s: acquired sslot %d from SCRATCH after queueing sslot %d", __func__,
+                    item.mSlot, sslot);
         mFbProducerSlot = mapSource2ProducerSlot(SOURCE_SCRATCH, item.mSlot);
         mFbFence = mSlots[item.mSlot].mFence;
 
     } else {
-        LOG_FATAL_IF(mCompositionType != COMPOSITION_GPU,
-                     "Unexpected queueBuffer in state %s for compositionType %s", dbgStateStr(),
-                     dbgCompositionTypeStr(mCompositionType));
+        LOG_FATAL_IF(mCompositionType != CompositionType::Gpu,
+                     "Unexpected %s in state %s for composition type %s", __func__,
+                     ftl::enum_string(mDebugState).c_str(), toString(mCompositionType).c_str());
 
         // Extract the GPU release fence for HWC to acquire
         int64_t timestamp;
@@ -533,9 +510,9 @@
         return mSource[SOURCE_SINK]->cancelBuffer(mapProducer2SourceSlot(SOURCE_SINK, pslot), fence);
     }
 
-    VDS_LOGW_IF(mDbgState != DBG_STATE_GPU, "Unexpected cancelBuffer(pslot=%d) in %s state", pslot,
-                dbgStateStr());
-    VDS_LOGV("cancelBuffer pslot=%d", pslot);
+    VDS_LOGW_IF(mDebugState != DebugState::Gpu, "Unexpected %s(pslot=%d) in %s state", __func__,
+                pslot, ftl::enum_string(mDebugState).c_str());
+    VDS_LOGV("%s pslot=%d", __func__, pslot);
     Source source = fbSourceForCompositionType(mCompositionType);
     return mSource[source]->cancelBuffer(
             mapProducer2SourceSlot(source, pslot), fence);
@@ -573,8 +550,8 @@
     return mSource[SOURCE_SINK]->disconnect(api, mode);
 }
 
-status_t VirtualDisplaySurface::setSidebandStream(const sp<NativeHandle>& /*stream*/) {
-    return INVALID_OPERATION;
+status_t VirtualDisplaySurface::setSidebandStream(const sp<NativeHandle>&) {
+    UNSUPPORTED();
 }
 
 void VirtualDisplaySurface::allocateBuffers(uint32_t /* width */,
@@ -586,40 +563,32 @@
     return INVALID_OPERATION;
 }
 
-status_t VirtualDisplaySurface::setGenerationNumber(uint32_t /* generation */) {
-    ALOGE("setGenerationNumber not supported on VirtualDisplaySurface");
-    return INVALID_OPERATION;
+status_t VirtualDisplaySurface::setGenerationNumber(uint32_t) {
+    UNSUPPORTED();
 }
 
 String8 VirtualDisplaySurface::getConsumerName() const {
     return String8("VirtualDisplaySurface");
 }
 
-status_t VirtualDisplaySurface::setSharedBufferMode(bool /*sharedBufferMode*/) {
-    ALOGE("setSharedBufferMode not supported on VirtualDisplaySurface");
-    return INVALID_OPERATION;
+status_t VirtualDisplaySurface::setSharedBufferMode(bool) {
+    UNSUPPORTED();
 }
 
-status_t VirtualDisplaySurface::setAutoRefresh(bool /*autoRefresh*/) {
-    ALOGE("setAutoRefresh not supported on VirtualDisplaySurface");
-    return INVALID_OPERATION;
+status_t VirtualDisplaySurface::setAutoRefresh(bool) {
+    UNSUPPORTED();
 }
 
-status_t VirtualDisplaySurface::setDequeueTimeout(nsecs_t /* timeout */) {
-    ALOGE("setDequeueTimeout not supported on VirtualDisplaySurface");
-    return INVALID_OPERATION;
+status_t VirtualDisplaySurface::setDequeueTimeout(nsecs_t) {
+    UNSUPPORTED();
 }
 
-status_t VirtualDisplaySurface::getLastQueuedBuffer(
-        sp<GraphicBuffer>* /*outBuffer*/, sp<Fence>* /*outFence*/,
-        float[16] /* outTransformMatrix*/) {
-    ALOGE("getLastQueuedBuffer not supported on VirtualDisplaySurface");
-    return INVALID_OPERATION;
+status_t VirtualDisplaySurface::getLastQueuedBuffer(sp<GraphicBuffer>*, sp<Fence>*, float[16]) {
+    UNSUPPORTED();
 }
 
-status_t VirtualDisplaySurface::getUniqueId(uint64_t* /*outId*/) const {
-    ALOGE("getUniqueId not supported on VirtualDisplaySurface");
-    return INVALID_OPERATION;
+status_t VirtualDisplaySurface::getUniqueId(uint64_t*) const {
+    UNSUPPORTED();
 }
 
 status_t VirtualDisplaySurface::getConsumerUsage(uint64_t* outUsage) const {
@@ -633,7 +602,7 @@
 }
 
 void VirtualDisplaySurface::resetPerFrameState() {
-    mCompositionType = COMPOSITION_UNKNOWN;
+    mCompositionType = CompositionType::Unknown;
     mFbFence = Fence::NO_FENCE;
     mOutputFence = Fence::NO_FENCE;
     mOutputProducerSlot = -1;
@@ -682,39 +651,16 @@
     return mapSource2ProducerSlot(source, pslot);
 }
 
-VirtualDisplaySurface::Source
-VirtualDisplaySurface::fbSourceForCompositionType(CompositionType type) {
-    return type == COMPOSITION_MIXED ? SOURCE_SCRATCH : SOURCE_SINK;
+auto VirtualDisplaySurface::fbSourceForCompositionType(CompositionType type) -> Source {
+    return type == CompositionType::Mixed ? SOURCE_SCRATCH : SOURCE_SINK;
 }
 
-const char* VirtualDisplaySurface::dbgStateStr() const {
-    switch (mDbgState) {
-        case DBG_STATE_IDLE:
-            return "IDLE";
-        case DBG_STATE_PREPARED:
-            return "PREPARED";
-        case DBG_STATE_GPU:
-            return "GPU";
-        case DBG_STATE_GPU_DONE:
-            return "GPU_DONE";
-        case DBG_STATE_HWC:
-            return "HWC";
-        default:
-            return "INVALID";
-    }
+std::string VirtualDisplaySurface::toString(CompositionType type) {
+    using namespace std::literals;
+    return type == CompositionType::Unknown ? "Unknown"s : Flags(type).string();
 }
 
-const char* VirtualDisplaySurface::dbgSourceStr(Source s) {
-    switch (s) {
-        case SOURCE_SINK:    return "SINK";
-        case SOURCE_SCRATCH: return "SCRATCH";
-        default:             return "INVALID";
-    }
-}
-
-// ---------------------------------------------------------------------------
 } // namespace android
-// ---------------------------------------------------------------------------
 
 // TODO(b/129481165): remove the #pragma below and fix conversion issues
 #pragma clang diagnostic pop // ignored "-Wconversion"
diff --git a/services/surfaceflinger/DisplayHardware/VirtualDisplaySurface.h b/services/surfaceflinger/DisplayHardware/VirtualDisplaySurface.h
index bbb6306..7720713 100644
--- a/services/surfaceflinger/DisplayHardware/VirtualDisplaySurface.h
+++ b/services/surfaceflinger/DisplayHardware/VirtualDisplaySurface.h
@@ -14,8 +14,7 @@
  * limitations under the License.
  */
 
-#ifndef ANDROID_SF_VIRTUAL_DISPLAY_SURFACE_H
-#define ANDROID_SF_VIRTUAL_DISPLAY_SURFACE_H
+#pragma once
 
 #include <optional>
 #include <string>
@@ -28,9 +27,7 @@
 
 #include "DisplayIdentification.h"
 
-// ---------------------------------------------------------------------------
 namespace android {
-// ---------------------------------------------------------------------------
 
 class HWComposer;
 class IProducerListener;
@@ -94,7 +91,13 @@
     virtual const sp<Fence>& getClientTargetAcquireFence() const override;
 
 private:
-    enum Source {SOURCE_SINK = 0, SOURCE_SCRATCH = 1};
+    enum Source : size_t {
+        SOURCE_SINK = 0,
+        SOURCE_SCRATCH = 1,
+
+        ftl_first = SOURCE_SINK,
+        ftl_last = SOURCE_SCRATCH,
+    };
 
     virtual ~VirtualDisplaySurface();
 
@@ -133,6 +136,8 @@
     // Utility methods
     //
     static Source fbSourceForCompositionType(CompositionType);
+    static std::string toString(CompositionType);
+
     status_t dequeueBuffer(Source, PixelFormat, uint64_t usage, int* sslot, sp<Fence>*);
     void updateQueueBufferOutput(QueueBufferOutput&&);
     void resetPerFrameState();
@@ -197,7 +202,7 @@
 
     // Composition type and graphics buffer source for the current frame.
     // Valid after prepareFrame(), cleared in onFrameCommitted.
-    CompositionType mCompositionType;
+    CompositionType mCompositionType = CompositionType::Unknown;
 
     // mFbFence is the fence HWC should wait for before reading the framebuffer
     // target buffer.
@@ -219,47 +224,42 @@
     // +-----------+-------------------+-------------+
     // | State     | Event             || Next State |
     // +-----------+-------------------+-------------+
-    // | IDLE      | beginFrame        || BEGUN      |
-    // | BEGUN     | prepareFrame      || PREPARED   |
-    // | PREPARED  | dequeueBuffer [1] || GPU        |
-    // | PREPARED  | advanceFrame [2]  || HWC        |
-    // | GPU       | queueBuffer       || GPU_DONE   |
-    // | GPU_DONE  | advanceFrame      || HWC        |
-    // | HWC       | onFrameCommitted  || IDLE       |
+    // | Idle      | beginFrame        || Begun      |
+    // | Begun     | prepareFrame      || Prepared   |
+    // | Prepared  | dequeueBuffer [1] || Gpu        |
+    // | Prepared  | advanceFrame [2]  || Hwc        |
+    // | Gpu       | queueBuffer       || GpuDone    |
+    // | GpuDone   | advanceFrame      || Hwc        |
+    // | Hwc       | onFrameCommitted  || Idle       |
     // +-----------+-------------------++------------+
-    // [1] COMPOSITION_GPU and COMPOSITION_MIXED frames.
-    // [2] COMPOSITION_HWC frames.
+    // [1] CompositionType::Gpu and CompositionType::Mixed frames.
+    // [2] CompositionType::Hwc frames.
     //
-    enum DbgState {
+    enum class DebugState {
         // no buffer dequeued, don't know anything about the next frame
-        DBG_STATE_IDLE,
+        Idle,
         // output buffer dequeued, framebuffer source not yet known
-        DBG_STATE_BEGUN,
+        Begun,
         // output buffer dequeued, framebuffer source known but not provided
         // to GPU yet.
-        DBG_STATE_PREPARED,
+        Prepared,
         // GPU driver has a buffer dequeued
-        DBG_STATE_GPU,
+        Gpu,
         // GPU driver has queued the buffer, we haven't sent it to HWC yet
-        DBG_STATE_GPU_DONE,
+        GpuDone,
         // HWC has the buffer for this frame
-        DBG_STATE_HWC,
+        Hwc,
+
+        ftl_last = Hwc
     };
-    DbgState mDbgState;
-    CompositionType mDbgLastCompositionType;
+    DebugState mDebugState = DebugState::Idle;
+    CompositionType mDebugLastCompositionType = CompositionType::Unknown;
 
-    const char* dbgStateStr() const;
-    static const char* dbgSourceStr(Source s);
-
-    bool mMustRecompose;
+    bool mMustRecompose = false;
 
     compositionengine::impl::HwcBufferCache mHwcBufferCache;
 
     bool mForceHwcCopy;
 };
 
-// ---------------------------------------------------------------------------
 } // namespace android
-// ---------------------------------------------------------------------------
-
-#endif // ANDROID_SF_VIRTUAL_DISPLAY_SURFACE_H
diff --git a/services/surfaceflinger/FrameTimeline/FrameTimeline.cpp b/services/surfaceflinger/FrameTimeline/FrameTimeline.cpp
index c294ff2..0c4e112 100644
--- a/services/surfaceflinger/FrameTimeline/FrameTimeline.cpp
+++ b/services/surfaceflinger/FrameTimeline/FrameTimeline.cpp
@@ -304,7 +304,7 @@
                            frametimeline::TimelineItem&& predictions,
                            std::shared_ptr<TimeStats> timeStats,
                            JankClassificationThresholds thresholds,
-                           TraceCookieCounter* traceCookieCounter, bool isBuffer, int32_t gameMode)
+                           TraceCookieCounter* traceCookieCounter, bool isBuffer, GameMode gameMode)
       : mToken(frameTimelineInfo.vsyncId),
         mInputEventId(frameTimelineInfo.inputEventId),
         mOwnerPid(ownerPid),
@@ -778,7 +778,7 @@
 
 std::shared_ptr<SurfaceFrame> FrameTimeline::createSurfaceFrameForToken(
         const FrameTimelineInfo& frameTimelineInfo, pid_t ownerPid, uid_t ownerUid, int32_t layerId,
-        std::string layerName, std::string debugName, bool isBuffer, int32_t gameMode) {
+        std::string layerName, std::string debugName, bool isBuffer, GameMode gameMode) {
     ATRACE_CALL();
     if (frameTimelineInfo.vsyncId == FrameTimelineInfo::INVALID_VSYNC_ID) {
         return std::make_shared<SurfaceFrame>(frameTimelineInfo, ownerPid, ownerUid, layerId,
diff --git a/services/surfaceflinger/FrameTimeline/FrameTimeline.h b/services/surfaceflinger/FrameTimeline/FrameTimeline.h
index d08344e..36d6290 100644
--- a/services/surfaceflinger/FrameTimeline/FrameTimeline.h
+++ b/services/surfaceflinger/FrameTimeline/FrameTimeline.h
@@ -26,6 +26,7 @@
 
 #include <gui/ISurfaceComposer.h>
 #include <gui/JankInfo.h>
+#include <gui/LayerMetadata.h>
 #include <perfetto/trace/android/frame_timeline_event.pbzero.h>
 #include <perfetto/tracing.h>
 #include <ui/FenceTime.h>
@@ -161,7 +162,7 @@
                  int32_t layerId, std::string layerName, std::string debugName,
                  PredictionState predictionState, TimelineItem&& predictions,
                  std::shared_ptr<TimeStats> timeStats, JankClassificationThresholds thresholds,
-                 TraceCookieCounter* traceCookieCounter, bool isBuffer, int32_t gameMode);
+                 TraceCookieCounter* traceCookieCounter, bool isBuffer, GameMode);
     ~SurfaceFrame() = default;
 
     // Returns std::nullopt if the frame hasn't been classified yet.
@@ -267,7 +268,7 @@
     // buffer(animations)
     bool mIsBuffer;
     // GameMode from the layer. Used in metrics.
-    int32_t mGameMode = 0;
+    GameMode mGameMode = GameMode::Unsupported;
 };
 
 /*
@@ -288,7 +289,7 @@
     virtual std::shared_ptr<SurfaceFrame> createSurfaceFrameForToken(
             const FrameTimelineInfo& frameTimelineInfo, pid_t ownerPid, uid_t ownerUid,
             int32_t layerId, std::string layerName, std::string debugName, bool isBuffer,
-            int32_t gameMode) = 0;
+            GameMode) = 0;
 
     // Adds a new SurfaceFrame to the current DisplayFrame. Frames from multiple layers can be
     // composited into one display frame.
@@ -448,7 +449,7 @@
     std::shared_ptr<SurfaceFrame> createSurfaceFrameForToken(
             const FrameTimelineInfo& frameTimelineInfo, pid_t ownerPid, uid_t ownerUid,
             int32_t layerId, std::string layerName, std::string debugName, bool isBuffer,
-            int32_t gameMode) override;
+            GameMode) override;
     void addSurfaceFrame(std::shared_ptr<frametimeline::SurfaceFrame> surfaceFrame) override;
     void setSfWakeUp(int64_t token, nsecs_t wakeupTime, Fps refreshRate) override;
     void setSfPresent(nsecs_t sfPresentTime, const std::shared_ptr<FenceTime>& presentFence,
diff --git a/services/surfaceflinger/Layer.cpp b/services/surfaceflinger/Layer.cpp
index 968a49d..67f9a92 100644
--- a/services/surfaceflinger/Layer.cpp
+++ b/services/surfaceflinger/Layer.cpp
@@ -36,6 +36,7 @@
 #include <cutils/compiler.h>
 #include <cutils/native_handle.h>
 #include <cutils/properties.h>
+#include <ftl/enum.h>
 #include <gui/BufferItem.h>
 #include <gui/LayerDebugInfo.h>
 #include <gui/Surface.h>
@@ -1411,19 +1412,6 @@
     result.append("\n");
 }
 
-std::string Layer::frameRateCompatibilityString(Layer::FrameRateCompatibility compatibility) {
-    switch (compatibility) {
-        case FrameRateCompatibility::Default:
-            return "Default";
-        case FrameRateCompatibility::ExactOrMultiple:
-            return "ExactOrMultiple";
-        case FrameRateCompatibility::NoVote:
-            return "NoVote";
-        case FrameRateCompatibility::Exact:
-            return "Exact";
-    }
-}
-
 void Layer::miniDump(std::string& result, const DisplayDevice& display) const {
     const auto outputLayer = findOutputLayerForDisplay(&display);
     if (!outputLayer) {
@@ -1462,8 +1450,8 @@
     const auto frameRate = getFrameRateForLayerTree();
     if (frameRate.rate.isValid() || frameRate.type != FrameRateCompatibility::Default) {
         StringAppendF(&result, "%s %15s %17s", to_string(frameRate.rate).c_str(),
-                      frameRateCompatibilityString(frameRate.type).c_str(),
-                      toString(frameRate.seamlessness).c_str());
+                      ftl::enum_string(frameRate.type).c_str(),
+                      ftl::enum_string(frameRate.seamlessness).c_str());
     } else {
         result.append(41, ' ');
     }
@@ -1546,11 +1534,10 @@
     return count;
 }
 
-void Layer::setGameModeForTree(int parentGameMode) {
-    int gameMode = parentGameMode;
-    auto& currentState = getDrawingState();
+void Layer::setGameModeForTree(GameMode gameMode) {
+    const auto& currentState = getDrawingState();
     if (currentState.metadata.has(METADATA_GAME_MODE)) {
-        gameMode = currentState.metadata.getInt32(METADATA_GAME_MODE, 0);
+        gameMode = static_cast<GameMode>(currentState.metadata.getInt32(METADATA_GAME_MODE, 0));
     }
     setGameMode(gameMode);
     for (const sp<Layer>& child : mCurrentChildren) {
@@ -1576,7 +1563,7 @@
     const auto removeResult = mCurrentChildren.remove(layer);
 
     updateTreeHasFrameRateVote();
-    layer->setGameModeForTree(0);
+    layer->setGameModeForTree(GameMode::Unsupported);
     layer->updateTreeHasFrameRateVote();
 
     return removeResult;
@@ -2631,12 +2618,11 @@
 // ---------------------------------------------------------------------------
 
 std::ostream& operator<<(std::ostream& stream, const Layer::FrameRate& rate) {
-    return stream << "{rate=" << rate.rate
-                  << " type=" << Layer::frameRateCompatibilityString(rate.type)
-                  << " seamlessness=" << toString(rate.seamlessness) << "}";
+    return stream << "{rate=" << rate.rate << " type=" << ftl::enum_string(rate.type)
+                  << " seamlessness=" << ftl::enum_string(rate.seamlessness) << '}';
 }
 
-}; // namespace android
+} // namespace android
 
 #if defined(__gl_h_)
 #error "don't include gl/gl.h in this file"
diff --git a/services/surfaceflinger/Layer.h b/services/surfaceflinger/Layer.h
index 041b439..47885a4 100644
--- a/services/surfaceflinger/Layer.h
+++ b/services/surfaceflinger/Layer.h
@@ -328,7 +328,6 @@
 
     static bool isLayerFocusedBasedOnPriority(int32_t priority);
     static void miniDumpHeader(std::string& result);
-    static std::string frameRateCompatibilityString(FrameRateCompatibility compatibility);
 
     // Provide unique string for each class type in the Layer hierarchy
     virtual const char* getType() const = 0;
@@ -854,12 +853,12 @@
      */
     bool hasInputInfo() const;
 
-    // Sets the parent's gameMode for this layer and all its children. Parent's gameMode is applied
-    // only to layers that do not have the GAME_MODE_METADATA set by WMShell. Any layer(along with
-    // its children) that has the metadata set will use the gameMode from the metadata.
-    void setGameModeForTree(int32_t parentGameMode);
-    void setGameMode(int32_t gameMode) { mGameMode = gameMode; };
-    int32_t getGameMode() const { return mGameMode; }
+    // Sets the GameMode for the tree rooted at this layer. A layer in the tree inherits this
+    // GameMode unless it (or an ancestor) has GAME_MODE_METADATA.
+    void setGameModeForTree(GameMode);
+
+    void setGameMode(GameMode gameMode) { mGameMode = gameMode; }
+    GameMode getGameMode() const { return mGameMode; }
 
     virtual uid_t getOwnerUid() const { return mOwnerUid; }
 
@@ -1110,9 +1109,8 @@
     // shadow radius is the set shadow radius, otherwise its the parent's shadow radius.
     float mEffectiveShadowRadius = 0.f;
 
-    // Game mode for the layer. Set by WindowManagerShell, game mode is used in
-    // metrics(SurfaceFlingerStats).
-    int32_t mGameMode = 0;
+    // Game mode for the layer. Set by WindowManagerShell and recorded by SurfaceFlingerStats.
+    GameMode mGameMode = GameMode::Unsupported;
 
     // A list of regions on this layer that should have blurs.
     const std::vector<BlurRegion> getBlurRegions() const;
diff --git a/services/surfaceflinger/Scheduler/LayerInfo.cpp b/services/surfaceflinger/Scheduler/LayerInfo.cpp
index 314526a..ae61eeb 100644
--- a/services/surfaceflinger/Scheduler/LayerInfo.cpp
+++ b/services/surfaceflinger/Scheduler/LayerInfo.cpp
@@ -28,6 +28,7 @@
 
 #include <cutils/compiler.h>
 #include <cutils/trace.h>
+#include <ftl/enum.h>
 
 #undef LOG_TAG
 #define LOG_TAG "LayerInfo"
@@ -257,10 +258,10 @@
     return {LayerHistory::LayerVoteType::Max, Fps()};
 }
 
-const char* LayerInfo::getTraceTag(android::scheduler::LayerHistory::LayerVoteType type) const {
+const char* LayerInfo::getTraceTag(LayerHistory::LayerVoteType type) const {
     if (mTraceTags.count(type) == 0) {
-        const auto tag = "LFPS " + mName + " " + RefreshRateConfigs::layerVoteTypeString(type);
-        mTraceTags.emplace(type, tag);
+        auto tag = "LFPS " + mName + " " + ftl::enum_string(type);
+        mTraceTags.emplace(type, std::move(tag));
     }
 
     return mTraceTags.at(type).c_str();
diff --git a/services/surfaceflinger/Scheduler/LayerInfo.h b/services/surfaceflinger/Scheduler/LayerInfo.h
index 18ed95e..690abda 100644
--- a/services/surfaceflinger/Scheduler/LayerInfo.h
+++ b/services/surfaceflinger/Scheduler/LayerInfo.h
@@ -82,6 +82,8 @@
 
         NoVote, // Layer doesn't have any requirements for the refresh rate and
                 // should not be considered when the display refresh rate is determined.
+
+        ftl_last = NoVote
     };
 
     // Encapsulates the frame rate and compatibility of the layer. This information will be used
diff --git a/services/surfaceflinger/Scheduler/RefreshRateConfigs.cpp b/services/surfaceflinger/Scheduler/RefreshRateConfigs.cpp
index 0d17b0c..71d5631 100644
--- a/services/surfaceflinger/Scheduler/RefreshRateConfigs.cpp
+++ b/services/surfaceflinger/Scheduler/RefreshRateConfigs.cpp
@@ -21,23 +21,27 @@
 #pragma clang diagnostic push
 #pragma clang diagnostic ignored "-Wextra"
 
-#include "RefreshRateConfigs.h"
-#include <android-base/properties.h>
-#include <android-base/stringprintf.h>
-#include <utils/Trace.h>
 #include <chrono>
 #include <cmath>
+
+#include <android-base/properties.h>
+#include <android-base/stringprintf.h>
+#include <ftl/enum.h>
+#include <utils/Trace.h>
+
 #include "../SurfaceFlingerProperties.h"
+#include "RefreshRateConfigs.h"
 
 #undef LOG_TAG
 #define LOG_TAG "RefreshRateConfigs"
 
 namespace android::scheduler {
 namespace {
+
 std::string formatLayerInfo(const RefreshRateConfigs::LayerRequirement& layer, float weight) {
     return base::StringPrintf("%s (type=%s, weight=%.2f seamlessness=%s) %s", layer.name.c_str(),
-                              RefreshRateConfigs::layerVoteTypeString(layer.vote).c_str(), weight,
-                              toString(layer.seamlessness).c_str(),
+                              ftl::enum_string(layer.vote).c_str(), weight,
+                              ftl::enum_string(layer.seamlessness).c_str(),
                               to_string(layer.desiredRefreshRate).c_str());
 }
 
@@ -74,25 +78,6 @@
                               mode->getWidth(), mode->getHeight(), getModeGroup());
 }
 
-std::string RefreshRateConfigs::layerVoteTypeString(LayerVoteType vote) {
-    switch (vote) {
-        case LayerVoteType::NoVote:
-            return "NoVote";
-        case LayerVoteType::Min:
-            return "Min";
-        case LayerVoteType::Max:
-            return "Max";
-        case LayerVoteType::Heuristic:
-            return "Heuristic";
-        case LayerVoteType::ExplicitDefault:
-            return "ExplicitDefault";
-        case LayerVoteType::ExplicitExactOrMultiple:
-            return "ExplicitExactOrMultiple";
-        case LayerVoteType::ExplicitExact:
-            return "ExplicitExact";
-    }
-}
-
 std::string RefreshRateConfigs::Policy::toString() const {
     return base::StringPrintf("default mode ID: %d, allowGroupSwitching = %d"
                               ", primary range: %s, app request range: %s",
@@ -405,7 +390,7 @@
 
     for (const auto& layer : layers) {
         ALOGV("Calculating score for %s (%s, weight %.2f, desired %.2f) ", layer.name.c_str(),
-              layerVoteTypeString(layer.vote).c_str(), layer.weight,
+              ftl::enum_string(layer.vote).c_str(), layer.weight,
               layer.desiredRefreshRate.getValue());
         if (layer.vote == LayerVoteType::NoVote || layer.vote == LayerVoteType::Min) {
             continue;
diff --git a/services/surfaceflinger/Scheduler/RefreshRateConfigs.h b/services/surfaceflinger/Scheduler/RefreshRateConfigs.h
index 8a1c206..8c38083 100644
--- a/services/surfaceflinger/Scheduler/RefreshRateConfigs.h
+++ b/services/surfaceflinger/Scheduler/RefreshRateConfigs.h
@@ -206,6 +206,7 @@
         ExplicitExact,           // Specific refresh rate that was provided by the app with
                                  // Exact compatibility
 
+        ftl_last = ExplicitExact
     };
 
     // Captures the layer requirements for a refresh rate. This will be used to determine the
@@ -285,9 +286,6 @@
     // Stores the current modeId the device operates at
     void setCurrentModeId(DisplayModeId) EXCLUDES(mLock);
 
-    // Returns a string that represents the layer vote type
-    static std::string layerVoteTypeString(LayerVoteType vote);
-
     // Returns a known frame rate that is the closest to frameRate
     Fps findClosestKnownFrameRate(Fps frameRate) const;
 
diff --git a/services/surfaceflinger/Scheduler/Timer.cpp b/services/surfaceflinger/Scheduler/Timer.cpp
index c9c2d84..22c3a70 100644
--- a/services/surfaceflinger/Scheduler/Timer.cpp
+++ b/services/surfaceflinger/Scheduler/Timer.cpp
@@ -17,14 +17,18 @@
 #undef LOG_TAG
 #define LOG_TAG "SchedulerTimer"
 #define ATRACE_TAG ATRACE_TAG_GRAPHICS
-#include <android-base/stringprintf.h>
-#include <log/log.h>
+
+#include <chrono>
+#include <cstdint>
+
 #include <sys/epoll.h>
 #include <sys/timerfd.h>
 #include <sys/unistd.h>
+
+#include <android-base/stringprintf.h>
+#include <ftl/enum.h>
+#include <log/log.h>
 #include <utils/Trace.h>
-#include <chrono>
-#include <cstdint>
 
 #include "SchedulerUtils.h"
 #include "Timer.h"
@@ -215,26 +219,9 @@
     mDebugState = state;
 }
 
-const char* Timer::strDebugState(DebugState state) const {
-    switch (state) {
-        case DebugState::Reset:
-            return "Reset";
-        case DebugState::Running:
-            return "Running";
-        case DebugState::Waiting:
-            return "Waiting";
-        case DebugState::Reading:
-            return "Reading";
-        case DebugState::InCallback:
-            return "InCallback";
-        case DebugState::Terminated:
-            return "Terminated";
-    }
-}
-
 void Timer::dump(std::string& result) const {
     std::lock_guard lock(mMutex);
-    StringAppendF(&result, "\t\tDebugState: %s\n", strDebugState(mDebugState));
+    StringAppendF(&result, "\t\tDebugState: %s\n", ftl::enum_string(mDebugState).c_str());
 }
 
 } // namespace android::scheduler
diff --git a/services/surfaceflinger/Scheduler/Timer.h b/services/surfaceflinger/Scheduler/Timer.h
index 69ce079..628d800 100644
--- a/services/surfaceflinger/Scheduler/Timer.h
+++ b/services/surfaceflinger/Scheduler/Timer.h
@@ -37,11 +37,20 @@
     void dump(std::string& result) const final;
 
 private:
-    enum class DebugState { Reset, Running, Waiting, Reading, InCallback, Terminated };
+    enum class DebugState {
+        Reset,
+        Running,
+        Waiting,
+        Reading,
+        InCallback,
+        Terminated,
+
+        ftl_last = Terminated
+    };
+
     void reset();
     void cleanup();
     void setDebugState(DebugState state) EXCLUDES(mMutex);
-    const char* strDebugState(DebugState state) const;
 
     int mTimerFd = -1;
     int mEpollFd = -1;
diff --git a/services/surfaceflinger/Scheduler/include/scheduler/Seamlessness.h b/services/surfaceflinger/Scheduler/include/scheduler/Seamlessness.h
index d7667ec..93bf726 100644
--- a/services/surfaceflinger/Scheduler/include/scheduler/Seamlessness.h
+++ b/services/surfaceflinger/Scheduler/include/scheduler/Seamlessness.h
@@ -17,7 +17,8 @@
 #pragma once
 
 #include <ostream>
-#include <string>
+
+#include <ftl/enum.h>
 
 namespace android::scheduler {
 
@@ -30,23 +31,14 @@
     // Indicates no preference for seamlessness. For such layers the system will
     // prefer seamless switches, but also non-seamless switches to the group of the
     // default config are allowed.
-    Default
+    Default,
+
+    ftl_last = Default
 };
 
-inline std::string toString(Seamlessness seamlessness) {
-    switch (seamlessness) {
-        case Seamlessness::OnlySeamless:
-            return "OnlySeamless";
-        case Seamlessness::SeamedAndSeamless:
-            return "SeamedAndSeamless";
-        case Seamlessness::Default:
-            return "Default";
-    }
-}
-
 // Used by gtest
-inline std::ostream& operator<<(std::ostream& os, Seamlessness val) {
-    return os << toString(val);
+inline std::ostream& operator<<(std::ostream& os, Seamlessness s) {
+    return os << ftl::enum_string(s);
 }
 
 } // namespace android::scheduler
diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index e497d95..0a6eb4f 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -4158,13 +4158,14 @@
     std::optional<nsecs_t> dequeueBufferTimestamp;
     if (what & layer_state_t::eMetadataChanged) {
         dequeueBufferTimestamp = s.metadata.getInt64(METADATA_DEQUEUE_TIME);
-        auto gameMode = s.metadata.getInt32(METADATA_GAME_MODE, -1);
-        if (gameMode != -1) {
+
+        if (const int32_t gameMode = s.metadata.getInt32(METADATA_GAME_MODE, -1); gameMode != -1) {
             // The transaction will be received on the Task layer and needs to be applied to all
             // child layers. Child layers that are added at a later point will obtain the game mode
             // info through addChild().
-            layer->setGameModeForTree(gameMode);
+            layer->setGameModeForTree(static_cast<GameMode>(gameMode));
         }
+
         if (layer->setMetadata(s.metadata)) flags |= eTraversalNeeded;
     }
     if (what & layer_state_t::eColorSpaceAgnosticChanged) {
diff --git a/services/surfaceflinger/TimeStats/TimeStats.cpp b/services/surfaceflinger/TimeStats/TimeStats.cpp
index bf2038b..b1a2bda 100644
--- a/services/surfaceflinger/TimeStats/TimeStats.cpp
+++ b/services/surfaceflinger/TimeStats/TimeStats.cpp
@@ -14,7 +14,6 @@
  * limitations under the License.
  */
 
-#include <unordered_map>
 #undef LOG_TAG
 #define LOG_TAG "TimeStats"
 #define ATRACE_TAG ATRACE_TAG_GRAPHICS
@@ -28,6 +27,7 @@
 
 #include <algorithm>
 #include <chrono>
+#include <unordered_map>
 
 #include "TimeStats.h"
 #include "timestatsproto/TimeStatsHelper.h"
@@ -58,15 +58,15 @@
     return histogramProto;
 }
 
-SurfaceflingerStatsLayerInfo_GameMode gameModeToProto(int32_t gameMode) {
+SurfaceflingerStatsLayerInfo_GameMode gameModeToProto(GameMode gameMode) {
     switch (gameMode) {
-        case TimeStatsHelper::GameModeUnsupported:
+        case GameMode::Unsupported:
             return SurfaceflingerStatsLayerInfo::GAME_MODE_UNSUPPORTED;
-        case TimeStatsHelper::GameModeStandard:
+        case GameMode::Standard:
             return SurfaceflingerStatsLayerInfo::GAME_MODE_STANDARD;
-        case TimeStatsHelper::GameModePerformance:
+        case GameMode::Performance:
             return SurfaceflingerStatsLayerInfo::GAME_MODE_PERFORMANCE;
-        case TimeStatsHelper::GameModeBattery:
+        case GameMode::Battery:
             return SurfaceflingerStatsLayerInfo::GAME_MODE_BATTERY;
         default:
             return SurfaceflingerStatsLayerInfo::GAME_MODE_UNSPECIFIED;
@@ -454,7 +454,7 @@
 void TimeStats::flushAvailableRecordsToStatsLocked(int32_t layerId, Fps displayRefreshRate,
                                                    std::optional<Fps> renderRate,
                                                    SetFrameRateVote frameRateVote,
-                                                   int32_t gameMode) {
+                                                   GameMode gameMode) {
     ATRACE_CALL();
     ALOGV("[%d]-flushAvailableRecordsToStatsLocked", layerId);
 
@@ -554,7 +554,7 @@
 }
 
 bool TimeStats::canAddNewAggregatedStats(uid_t uid, const std::string& layerName,
-                                         int32_t gameMode) {
+                                         GameMode gameMode) {
     uint32_t layerRecords = 0;
     for (const auto& record : mTimeStats.stats) {
         if (record.second.stats.count({uid, layerName, gameMode}) > 0) {
@@ -568,7 +568,7 @@
 }
 
 void TimeStats::setPostTime(int32_t layerId, uint64_t frameNumber, const std::string& layerName,
-                            uid_t uid, nsecs_t postTime, int32_t gameMode) {
+                            uid_t uid, nsecs_t postTime, GameMode gameMode) {
     if (!mEnabled.load()) return;
 
     ATRACE_CALL();
@@ -718,7 +718,7 @@
 
 void TimeStats::setPresentTime(int32_t layerId, uint64_t frameNumber, nsecs_t presentTime,
                                Fps displayRefreshRate, std::optional<Fps> renderRate,
-                               SetFrameRateVote frameRateVote, int32_t gameMode) {
+                               SetFrameRateVote frameRateVote, GameMode gameMode) {
     if (!mEnabled.load()) return;
 
     ATRACE_CALL();
@@ -744,7 +744,7 @@
 void TimeStats::setPresentFence(int32_t layerId, uint64_t frameNumber,
                                 const std::shared_ptr<FenceTime>& presentFence,
                                 Fps displayRefreshRate, std::optional<Fps> renderRate,
-                                SetFrameRateVote frameRateVote, int32_t gameMode) {
+                                SetFrameRateVote frameRateVote, GameMode gameMode) {
     if (!mEnabled.load()) return;
 
     ATRACE_CALL();
@@ -823,7 +823,7 @@
     // the first jank record is not dropped.
 
     static const std::string kDefaultLayerName = "none";
-    static constexpr int32_t kDefaultGameMode = TimeStatsHelper::GameModeUnsupported;
+    constexpr GameMode kDefaultGameMode = GameMode::Unsupported;
 
     const int32_t refreshRateBucket =
             clampToNearestBucket(info.refreshRate, REFRESH_RATE_BUCKET_WIDTH);
diff --git a/services/surfaceflinger/TimeStats/TimeStats.h b/services/surfaceflinger/TimeStats/TimeStats.h
index 23f19b5..77c7973 100644
--- a/services/surfaceflinger/TimeStats/TimeStats.h
+++ b/services/surfaceflinger/TimeStats/TimeStats.h
@@ -25,6 +25,7 @@
 
 #include <android/hardware/graphics/composer/2.4/IComposerClient.h>
 #include <gui/JankInfo.h>
+#include <gui/LayerMetadata.h>
 #include <timestatsproto/TimeStatsHelper.h>
 #include <timestatsproto/TimeStatsProtoHeader.h>
 #include <ui/FenceTime.h>
@@ -79,7 +80,7 @@
                                             const std::shared_ptr<FenceTime>& readyFence) = 0;
 
     virtual void setPostTime(int32_t layerId, uint64_t frameNumber, const std::string& layerName,
-                             uid_t uid, nsecs_t postTime, int32_t gameMode) = 0;
+                             uid_t uid, nsecs_t postTime, GameMode) = 0;
     virtual void setLatchTime(int32_t layerId, uint64_t frameNumber, nsecs_t latchTime) = 0;
     // Reasons why latching a particular buffer may be skipped
     enum class LatchSkipReason {
@@ -101,11 +102,11 @@
     // rendering path, as they flush prior fences if those fences have fired.
     virtual void setPresentTime(int32_t layerId, uint64_t frameNumber, nsecs_t presentTime,
                                 Fps displayRefreshRate, std::optional<Fps> renderRate,
-                                SetFrameRateVote frameRateVote, int32_t gameMode) = 0;
+                                SetFrameRateVote frameRateVote, GameMode) = 0;
     virtual void setPresentFence(int32_t layerId, uint64_t frameNumber,
                                  const std::shared_ptr<FenceTime>& presentFence,
                                  Fps displayRefreshRate, std::optional<Fps> renderRate,
-                                 SetFrameRateVote frameRateVote, int32_t gameMode) = 0;
+                                 SetFrameRateVote frameRateVote, GameMode) = 0;
 
     // Increments janky frames, blamed to the provided {refreshRate, renderRate, uid, layerName}
     // key, with JankMetadata as supplementary reasons for the jank. Because FrameTimeline is the
@@ -123,7 +124,7 @@
         std::optional<Fps> renderRate;
         uid_t uid = 0;
         std::string layerName;
-        int32_t gameMode = 0;
+        GameMode gameMode = GameMode::Unsupported;
         int32_t reasons = 0;
         nsecs_t displayDeadlineDelta = 0;
         nsecs_t displayPresentJitter = 0;
@@ -194,7 +195,7 @@
     struct LayerRecord {
         uid_t uid;
         std::string layerName;
-        int32_t gameMode = 0;
+        GameMode gameMode = GameMode::Unsupported;
         // This is the index in timeRecords, at which the timestamps for that
         // specific frame are still not fully received. This is not waiting for
         // fences to signal, but rather waiting to receive those fences/timestamps.
@@ -247,7 +248,7 @@
                                     const std::shared_ptr<FenceTime>& readyFence) override;
 
     void setPostTime(int32_t layerId, uint64_t frameNumber, const std::string& layerName, uid_t uid,
-                     nsecs_t postTime, int32_t gameMode) override;
+                     nsecs_t postTime, GameMode) override;
     void setLatchTime(int32_t layerId, uint64_t frameNumber, nsecs_t latchTime) override;
     void incrementLatchSkipped(int32_t layerId, LatchSkipReason reason) override;
     void incrementBadDesiredPresent(int32_t layerId) override;
@@ -256,12 +257,11 @@
     void setAcquireFence(int32_t layerId, uint64_t frameNumber,
                          const std::shared_ptr<FenceTime>& acquireFence) override;
     void setPresentTime(int32_t layerId, uint64_t frameNumber, nsecs_t presentTime,
-                        Fps displayRefreshRate, std::optional<Fps> renderRate,
-                        SetFrameRateVote frameRateVote, int32_t gameMode) override;
+                        Fps displayRefreshRate, std::optional<Fps> renderRate, SetFrameRateVote,
+                        GameMode) override;
     void setPresentFence(int32_t layerId, uint64_t frameNumber,
                          const std::shared_ptr<FenceTime>& presentFence, Fps displayRefreshRate,
-                         std::optional<Fps> renderRate, SetFrameRateVote frameRateVote,
-                         int32_t gameMode) override;
+                         std::optional<Fps> renderRate, SetFrameRateVote, GameMode) override;
 
     void incrementJankyFrames(const JankyFramesInfo& info) override;
     // Clean up the layer record
@@ -282,11 +282,11 @@
     bool populateLayerAtom(std::string* pulledData);
     bool recordReadyLocked(int32_t layerId, TimeRecord* timeRecord);
     void flushAvailableRecordsToStatsLocked(int32_t layerId, Fps displayRefreshRate,
-                                            std::optional<Fps> renderRate,
-                                            SetFrameRateVote frameRateVote, int32_t gameMode);
+                                            std::optional<Fps> renderRate, SetFrameRateVote,
+                                            GameMode);
     void flushPowerTimeLocked();
     void flushAvailableGlobalRecordsToStatsLocked();
-    bool canAddNewAggregatedStats(uid_t uid, const std::string& layerName, int32_t gameMode);
+    bool canAddNewAggregatedStats(uid_t uid, const std::string& layerName, GameMode);
 
     void enable();
     void disable();
diff --git a/services/surfaceflinger/TimeStats/timestatsproto/TimeStatsHelper.cpp b/services/surfaceflinger/TimeStats/timestatsproto/TimeStatsHelper.cpp
index ffb2f09..69afa2a 100644
--- a/services/surfaceflinger/TimeStats/timestatsproto/TimeStatsHelper.cpp
+++ b/services/surfaceflinger/TimeStats/timestatsproto/TimeStatsHelper.cpp
@@ -16,9 +16,10 @@
 #include "timestatsproto/TimeStatsHelper.h"
 
 #include <android-base/stringprintf.h>
-#include <inttypes.h>
+#include <ftl/enum.h>
 
 #include <array>
+#include <cinttypes>
 
 #define HISTOGRAM_SIZE 85
 
@@ -91,51 +92,15 @@
     return result;
 }
 
-std::string TimeStatsHelper::SetFrameRateVote::toString(FrameRateCompatibility compatibility) {
-    switch (compatibility) {
-        case FrameRateCompatibility::Undefined:
-            return "Undefined";
-        case FrameRateCompatibility::Default:
-            return "Default";
-        case FrameRateCompatibility::ExactOrMultiple:
-            return "ExactOrMultiple";
-    }
-}
-
-std::string TimeStatsHelper::SetFrameRateVote::toString(Seamlessness seamlessness) {
-    switch (seamlessness) {
-        case Seamlessness::Undefined:
-            return "Undefined";
-        case Seamlessness::ShouldBeSeamless:
-            return "ShouldBeSeamless";
-        case Seamlessness::NotRequired:
-            return "NotRequired";
-    }
-}
-
 std::string TimeStatsHelper::SetFrameRateVote::toString() const {
     std::string result;
     StringAppendF(&result, "frameRate = %.2f\n", frameRate);
     StringAppendF(&result, "frameRateCompatibility = %s\n",
-                  toString(frameRateCompatibility).c_str());
-    StringAppendF(&result, "seamlessness = %s\n", toString(seamlessness).c_str());
+                  ftl::enum_string(frameRateCompatibility).c_str());
+    StringAppendF(&result, "seamlessness = %s\n", ftl::enum_string(seamlessness).c_str());
     return result;
 }
 
-std::string TimeStatsHelper::TimeStatsLayer::toString(int32_t gameMode) const {
-    switch (gameMode) {
-        case TimeStatsHelper::GameModeUnsupported:
-            return "GameModeUnsupported";
-        case TimeStatsHelper::GameModeStandard:
-            return "GameModeStandard";
-        case TimeStatsHelper::GameModePerformance:
-            return "GameModePerformance";
-        case TimeStatsHelper::GameModeBattery:
-            return "GameModeBattery";
-        default:
-            return "GameModeUnspecified";
-    }
-}
 std::string TimeStatsHelper::TimeStatsLayer::toString() const {
     std::string result = "\n";
     StringAppendF(&result, "displayRefreshRate = %d fps\n", displayRefreshRateBucket);
@@ -143,7 +108,7 @@
     StringAppendF(&result, "uid = %d\n", uid);
     StringAppendF(&result, "layerName = %s\n", layerName.c_str());
     StringAppendF(&result, "packageName = %s\n", packageName.c_str());
-    StringAppendF(&result, "gameMode = %s\n", toString(gameMode).c_str());
+    StringAppendF(&result, "gameMode = %s\n", ftl::enum_string(gameMode).c_str());
     StringAppendF(&result, "totalFrames = %d\n", totalFrames);
     StringAppendF(&result, "droppedFrames = %d\n", droppedFrames);
     StringAppendF(&result, "lateAcquireFrames = %d\n", lateAcquireFrames);
diff --git a/services/surfaceflinger/TimeStats/timestatsproto/include/timestatsproto/TimeStatsHelper.h b/services/surfaceflinger/TimeStats/timestatsproto/include/timestatsproto/TimeStatsHelper.h
index 2afff8d..438561c 100644
--- a/services/surfaceflinger/TimeStats/timestatsproto/include/timestatsproto/TimeStatsHelper.h
+++ b/services/surfaceflinger/TimeStats/timestatsproto/include/timestatsproto/TimeStatsHelper.h
@@ -15,6 +15,7 @@
  */
 #pragma once
 
+#include <gui/LayerMetadata.h>
 #include <timestatsproto/TimeStatsProtoHeader.h>
 #include <utils/Timers.h>
 
@@ -63,6 +64,8 @@
             Undefined = 0,
             Default = 1,
             ExactOrMultiple = 2,
+
+            ftl_last = ExactOrMultiple
         } frameRateCompatibility = FrameRateCompatibility::Undefined;
 
         // Needs to be in sync with atoms.proto
@@ -70,25 +73,13 @@
             Undefined = 0,
             ShouldBeSeamless = 1,
             NotRequired = 2,
+
+            ftl_last = NotRequired
         } seamlessness = Seamlessness::Undefined;
 
-        static std::string toString(FrameRateCompatibility);
-        static std::string toString(Seamlessness);
         std::string toString() const;
     };
 
-    /**
-     * GameMode of the layer. GameModes are set by SysUI through WMShell.
-     * Actual game mode definitions are managed by GameManager.java
-     * The values defined here should always be in sync with the ones in GameManager.
-     */
-    enum GameMode {
-        GameModeUnsupported = 0,
-        GameModeStandard = 1,
-        GameModePerformance = 2,
-        GameModeBattery = 3,
-    };
-
     class TimeStatsLayer {
     public:
         uid_t uid;
@@ -96,7 +87,7 @@
         std::string packageName;
         int32_t displayRefreshRateBucket = 0;
         int32_t renderRateBucket = 0;
-        int32_t gameMode = 0;
+        GameMode gameMode = GameMode::Unsupported;
         int32_t totalFrames = 0;
         int32_t droppedFrames = 0;
         int32_t lateAcquireFrames = 0;
@@ -106,7 +97,6 @@
         std::unordered_map<std::string, Histogram> deltas;
 
         std::string toString() const;
-        std::string toString(int32_t gameMode) const;
         SFTimeStatsLayerProto toProto() const;
     };
 
@@ -137,13 +127,14 @@
     struct LayerStatsKey {
         uid_t uid = 0;
         std::string layerName;
-        int32_t gameMode = 0;
+        GameMode gameMode = GameMode::Unsupported;
 
         struct Hasher {
             size_t operator()(const LayerStatsKey& key) const {
                 size_t uidHash = std::hash<uid_t>{}(key.uid);
                 size_t layerNameHash = std::hash<std::string>{}(key.layerName);
-                size_t gameModeHash = std::hash<int32_t>{}(key.gameMode);
+                using T = std::underlying_type_t<GameMode>;
+                size_t gameModeHash = std::hash<T>{}(static_cast<T>(key.gameMode));
                 return HashCombine(uidHash, HashCombine(layerNameHash, gameModeHash));
             }
         };
diff --git a/services/surfaceflinger/tests/unittests/CompositionTest.cpp b/services/surfaceflinger/tests/unittests/CompositionTest.cpp
index 8d2c078..c7c6b06 100644
--- a/services/surfaceflinger/tests/unittests/CompositionTest.cpp
+++ b/services/surfaceflinger/tests/unittests/CompositionTest.cpp
@@ -370,7 +370,7 @@
         EXPECT_CALL(*test->mComposer, presentOrValidateDisplay(HWC_DISPLAY, _, _, _, _)).Times(1);
 
         EXPECT_CALL(*test->mDisplaySurface,
-                    prepareFrame(compositionengine::DisplaySurface::COMPOSITION_HWC))
+                    prepareFrame(compositionengine::DisplaySurface::CompositionType::Hwc))
                 .Times(1);
     }
 
@@ -384,7 +384,7 @@
 
     static void setupRECompositionCallExpectations(CompositionTest* test) {
         EXPECT_CALL(*test->mDisplaySurface,
-                    prepareFrame(compositionengine::DisplaySurface::COMPOSITION_GPU))
+                    prepareFrame(compositionengine::DisplaySurface::CompositionType::Gpu))
                 .Times(1);
         EXPECT_CALL(*test->mDisplaySurface, getClientTargetAcquireFence())
                 .WillRepeatedly(ReturnRef(test->mClientTargetAcquireFence));
diff --git a/services/surfaceflinger/tests/unittests/FrameTimelineTest.cpp b/services/surfaceflinger/tests/unittests/FrameTimelineTest.cpp
index 9fbaece..397c619 100644
--- a/services/surfaceflinger/tests/unittests/FrameTimelineTest.cpp
+++ b/services/surfaceflinger/tests/unittests/FrameTimelineTest.cpp
@@ -169,13 +169,14 @@
 
 static const std::string sLayerNameOne = "layer1";
 static const std::string sLayerNameTwo = "layer2";
-static constexpr const uid_t sUidOne = 0;
-static constexpr pid_t sPidOne = 10;
-static constexpr pid_t sPidTwo = 20;
-static constexpr int32_t sInputEventId = 5;
-static constexpr int32_t sLayerIdOne = 1;
-static constexpr int32_t sLayerIdTwo = 2;
-static constexpr int32_t sGameMode = 0;
+
+constexpr const uid_t sUidOne = 0;
+constexpr pid_t sPidOne = 10;
+constexpr pid_t sPidTwo = 20;
+constexpr int32_t sInputEventId = 5;
+constexpr int32_t sLayerIdOne = 1;
+constexpr int32_t sLayerIdTwo = 2;
+constexpr GameMode sGameMode = GameMode::Unsupported;
 
 TEST_F(FrameTimelineTest, tokenManagerRemovesStalePredictions) {
     int64_t token1 = mTokenManager->generateTokenForPredictions({0, 0, 0});
diff --git a/services/surfaceflinger/tests/unittests/GameModeTest.cpp b/services/surfaceflinger/tests/unittests/GameModeTest.cpp
index d645942..981ca1d 100644
--- a/services/surfaceflinger/tests/unittests/GameModeTest.cpp
+++ b/services/surfaceflinger/tests/unittests/GameModeTest.cpp
@@ -91,8 +91,8 @@
     }
 
     // Mocks the behavior of applying a transaction from WMShell
-    void setGameModeMetadata(sp<Layer> layer, int gameMode) {
-        mLayerMetadata.setInt32(METADATA_GAME_MODE, gameMode);
+    void setGameModeMetadata(sp<Layer> layer, GameMode gameMode) {
+        mLayerMetadata.setInt32(METADATA_GAME_MODE, static_cast<int32_t>(gameMode));
         layer->setMetadata(mLayerMetadata);
         layer->setGameModeForTree(gameMode);
     }
@@ -109,51 +109,52 @@
     sp<BufferStateLayer> childLayer2 = createBufferStateLayer();
     rootLayer->addChild(childLayer1);
     rootLayer->addChild(childLayer2);
-    rootLayer->setGameModeForTree(/*gameMode*/ 2);
+    rootLayer->setGameModeForTree(GameMode::Performance);
 
-    EXPECT_EQ(rootLayer->getGameMode(), 2);
-    EXPECT_EQ(childLayer1->getGameMode(), 2);
-    EXPECT_EQ(childLayer2->getGameMode(), 2);
+    EXPECT_EQ(rootLayer->getGameMode(), GameMode::Performance);
+    EXPECT_EQ(childLayer1->getGameMode(), GameMode::Performance);
+    EXPECT_EQ(childLayer2->getGameMode(), GameMode::Performance);
 }
 
 TEST_F(GameModeTest, AddChildAppliesGameModeFromParent) {
     sp<BufferStateLayer> rootLayer = createBufferStateLayer();
     sp<BufferStateLayer> childLayer = createBufferStateLayer();
-    rootLayer->setGameModeForTree(/*gameMode*/ 2);
+    rootLayer->setGameModeForTree(GameMode::Performance);
     rootLayer->addChild(childLayer);
 
-    EXPECT_EQ(rootLayer->getGameMode(), 2);
-    EXPECT_EQ(childLayer->getGameMode(), 2);
+    EXPECT_EQ(rootLayer->getGameMode(), GameMode::Performance);
+    EXPECT_EQ(childLayer->getGameMode(), GameMode::Performance);
 }
 
 TEST_F(GameModeTest, RemoveChildResetsGameMode) {
     sp<BufferStateLayer> rootLayer = createBufferStateLayer();
     sp<BufferStateLayer> childLayer = createBufferStateLayer();
-    rootLayer->setGameModeForTree(/*gameMode*/ 2);
+    rootLayer->setGameModeForTree(GameMode::Performance);
     rootLayer->addChild(childLayer);
 
-    EXPECT_EQ(rootLayer->getGameMode(), 2);
-    EXPECT_EQ(childLayer->getGameMode(), 2);
+    EXPECT_EQ(rootLayer->getGameMode(), GameMode::Performance);
+    EXPECT_EQ(childLayer->getGameMode(), GameMode::Performance);
 
     rootLayer->removeChild(childLayer);
-    EXPECT_EQ(childLayer->getGameMode(), 0);
+    EXPECT_EQ(childLayer->getGameMode(), GameMode::Unsupported);
 }
 
 TEST_F(GameModeTest, ReparentingDoesNotOverrideMetadata) {
     sp<BufferStateLayer> rootLayer = createBufferStateLayer();
     sp<BufferStateLayer> childLayer1 = createBufferStateLayer();
     sp<BufferStateLayer> childLayer2 = createBufferStateLayer();
-    rootLayer->setGameModeForTree(/*gameMode*/ 1);
+    rootLayer->setGameModeForTree(GameMode::Standard);
     rootLayer->addChild(childLayer1);
 
-    setGameModeMetadata(childLayer2, /*gameMode*/ 2);
+    setGameModeMetadata(childLayer2, GameMode::Performance);
     rootLayer->addChild(childLayer2);
 
-    EXPECT_EQ(rootLayer->getGameMode(), 1);
-    EXPECT_EQ(childLayer1->getGameMode(), 1);
-    EXPECT_EQ(childLayer2->getGameMode(), 2);
+    EXPECT_EQ(rootLayer->getGameMode(), GameMode::Standard);
+    EXPECT_EQ(childLayer1->getGameMode(), GameMode::Standard);
+    EXPECT_EQ(childLayer2->getGameMode(), GameMode::Performance);
 
     rootLayer->removeChild(childLayer2);
-    EXPECT_EQ(childLayer2->getGameMode(), 2);
+    EXPECT_EQ(childLayer2->getGameMode(), GameMode::Performance);
 }
-} // namespace android
\ No newline at end of file
+
+} // namespace android
diff --git a/services/surfaceflinger/tests/unittests/RefreshRateConfigsTest.cpp b/services/surfaceflinger/tests/unittests/RefreshRateConfigsTest.cpp
index fc84d48..98746bc 100644
--- a/services/surfaceflinger/tests/unittests/RefreshRateConfigsTest.cpp
+++ b/services/surfaceflinger/tests/unittests/RefreshRateConfigsTest.cpp
@@ -21,10 +21,9 @@
 #undef LOG_TAG
 #define LOG_TAG "SchedulerUnittests"
 
+#include <ftl/enum.h>
 #include <gmock/gmock.h>
 #include <log/log.h>
-#include <thread>
-
 #include <ui/Size.h>
 
 #include "DisplayHardware/HWC2.h"
@@ -1975,7 +1974,7 @@
         layers[0].vote = vote;
         EXPECT_EQ(fps.getIntValue(),
                   refreshRateConfigs->getBestRefreshRate(layers, {}).getFps().getIntValue())
-                << "Failed for " << RefreshRateConfigs::layerVoteTypeString(vote);
+                << "Failed for " << ftl::enum_string(vote);
     };
 
     for (int fps = kMinRefreshRate; fps < kMaxRefreshRate; fps++) {
diff --git a/services/surfaceflinger/tests/unittests/TimeStatsTest.cpp b/services/surfaceflinger/tests/unittests/TimeStatsTest.cpp
index 1487a96..0ef8456 100644
--- a/services/surfaceflinger/tests/unittests/TimeStatsTest.cpp
+++ b/services/surfaceflinger/tests/unittests/TimeStatsTest.cpp
@@ -70,9 +70,9 @@
 #define NUM_LAYERS            1
 #define NUM_LAYERS_INVALID    "INVALID"
 
-const constexpr Fps kRefreshRate0 = 61_Hz;
-const constexpr Fps kRenderRate0 = 31_Hz;
-static constexpr int32_t kGameMode = TimeStatsHelper::GameModeUnsupported;
+constexpr Fps kRefreshRate0 = 61_Hz;
+constexpr Fps kRenderRate0 = 31_Hz;
+constexpr GameMode kGameMode = GameMode::Unsupported;
 
 enum InputCommand : int32_t {
     ENABLE                 = 0,
@@ -145,14 +145,14 @@
     std::string inputCommand(InputCommand cmd, bool useProto);
 
     void setTimeStamp(TimeStamp type, int32_t id, uint64_t frameNumber, nsecs_t ts,
-                      TimeStats::SetFrameRateVote frameRateVote, int32_t gameMode);
+                      TimeStats::SetFrameRateVote, GameMode);
 
     int32_t genRandomInt32(int32_t begin, int32_t end);
 
     template <size_t N>
     void insertTimeRecord(const TimeStamp (&sequence)[N], int32_t id, uint64_t frameNumber,
                           nsecs_t ts, TimeStats::SetFrameRateVote frameRateVote = {},
-                          int32_t gameMode = kGameMode) {
+                          GameMode gameMode = kGameMode) {
         for (size_t i = 0; i < N; i++, ts += 1000000) {
             setTimeStamp(sequence[i], id, frameNumber, ts, frameRateVote, gameMode);
         }
@@ -203,7 +203,7 @@
 }
 
 void TimeStatsTest::setTimeStamp(TimeStamp type, int32_t id, uint64_t frameNumber, nsecs_t ts,
-                                 TimeStats::SetFrameRateVote frameRateVote, int32_t gameMode) {
+                                 TimeStats::SetFrameRateVote frameRateVote, GameMode gameMode) {
     switch (type) {
         case TimeStamp::POST:
             ASSERT_NO_FATAL_FAILURE(mTimeStats->setPostTime(id, frameNumber, genLayerName(id),
@@ -1168,8 +1168,7 @@
     constexpr nsecs_t APP_DEADLINE_DELTA_3MS = 3'000'000;
     EXPECT_TRUE(inputCommand(InputCommand::ENABLE, FMT_STRING).empty());
 
-    insertTimeRecord(NORMAL_SEQUENCE, LAYER_ID_0, 1, 1000000, {},
-                     TimeStatsHelper::GameModeStandard);
+    insertTimeRecord(NORMAL_SEQUENCE, LAYER_ID_0, 1, 1000000, {}, GameMode::Standard);
     for (size_t i = 0; i < LATE_ACQUIRE_FRAMES; i++) {
         mTimeStats->incrementLatchSkipped(LAYER_ID_0, TimeStats::LatchSkipReason::LateAcquire);
     }
@@ -1182,42 +1181,39 @@
                     TimeStats::SetFrameRateVote::FrameRateCompatibility::ExactOrMultiple,
             .seamlessness = TimeStats::SetFrameRateVote::Seamlessness::NotRequired,
     };
-    insertTimeRecord(NORMAL_SEQUENCE, LAYER_ID_0, 2, 2000000, frameRate60,
-                     TimeStatsHelper::GameModeStandard);
+    insertTimeRecord(NORMAL_SEQUENCE, LAYER_ID_0, 2, 2000000, frameRate60, GameMode::Standard);
 
-    mTimeStats->incrementJankyFrames(
-            {kRefreshRate0, kRenderRate0, UID_0, genLayerName(LAYER_ID_0),
-             TimeStatsHelper::GameModeStandard, JankType::SurfaceFlingerCpuDeadlineMissed,
-             DISPLAY_DEADLINE_DELTA, DISPLAY_PRESENT_JITTER, APP_DEADLINE_DELTA_3MS});
-    mTimeStats->incrementJankyFrames(
-            {kRefreshRate0, kRenderRate0, UID_0, genLayerName(LAYER_ID_0),
-             TimeStatsHelper::GameModeStandard, JankType::SurfaceFlingerGpuDeadlineMissed,
-             DISPLAY_DEADLINE_DELTA, DISPLAY_PRESENT_JITTER, APP_DEADLINE_DELTA_3MS});
     mTimeStats->incrementJankyFrames({kRefreshRate0, kRenderRate0, UID_0, genLayerName(LAYER_ID_0),
-                                      TimeStatsHelper::GameModeStandard, JankType::DisplayHAL,
+                                      GameMode::Standard, JankType::SurfaceFlingerCpuDeadlineMissed,
                                       DISPLAY_DEADLINE_DELTA, DISPLAY_PRESENT_JITTER,
                                       APP_DEADLINE_DELTA_3MS});
     mTimeStats->incrementJankyFrames({kRefreshRate0, kRenderRate0, UID_0, genLayerName(LAYER_ID_0),
-                                      TimeStatsHelper::GameModeStandard,
-                                      JankType::AppDeadlineMissed, DISPLAY_DEADLINE_DELTA,
+                                      GameMode::Standard, JankType::SurfaceFlingerGpuDeadlineMissed,
+                                      DISPLAY_DEADLINE_DELTA, DISPLAY_PRESENT_JITTER,
+                                      APP_DEADLINE_DELTA_3MS});
+    mTimeStats->incrementJankyFrames({kRefreshRate0, kRenderRate0, UID_0, genLayerName(LAYER_ID_0),
+                                      GameMode::Standard, JankType::DisplayHAL,
+                                      DISPLAY_DEADLINE_DELTA, DISPLAY_PRESENT_JITTER,
+                                      APP_DEADLINE_DELTA_3MS});
+    mTimeStats->incrementJankyFrames({kRefreshRate0, kRenderRate0, UID_0, genLayerName(LAYER_ID_0),
+                                      GameMode::Standard, JankType::AppDeadlineMissed,
+                                      DISPLAY_DEADLINE_DELTA, DISPLAY_PRESENT_JITTER,
+                                      APP_DEADLINE_DELTA_3MS});
+    mTimeStats->incrementJankyFrames({kRefreshRate0, kRenderRate0, UID_0, genLayerName(LAYER_ID_0),
+                                      GameMode::Standard, JankType::SurfaceFlingerScheduling,
+                                      DISPLAY_DEADLINE_DELTA, DISPLAY_PRESENT_JITTER,
+                                      APP_DEADLINE_DELTA_2MS});
+    mTimeStats->incrementJankyFrames({kRefreshRate0, kRenderRate0, UID_0, genLayerName(LAYER_ID_0),
+                                      GameMode::Standard, JankType::PredictionError,
+                                      DISPLAY_DEADLINE_DELTA, DISPLAY_PRESENT_JITTER,
+                                      APP_DEADLINE_DELTA_2MS});
+    mTimeStats->incrementJankyFrames(
+            {kRefreshRate0, kRenderRate0, UID_0, genLayerName(LAYER_ID_0), GameMode::Standard,
+             JankType::AppDeadlineMissed | JankType::BufferStuffing, DISPLAY_DEADLINE_DELTA,
+             APP_DEADLINE_DELTA_2MS, APP_DEADLINE_DELTA_2MS});
+    mTimeStats->incrementJankyFrames({kRefreshRate0, kRenderRate0, UID_0, genLayerName(LAYER_ID_0),
+                                      GameMode::Standard, JankType::None, DISPLAY_DEADLINE_DELTA,
                                       DISPLAY_PRESENT_JITTER, APP_DEADLINE_DELTA_3MS});
-    mTimeStats->incrementJankyFrames({kRefreshRate0, kRenderRate0, UID_0, genLayerName(LAYER_ID_0),
-                                      TimeStatsHelper::GameModeStandard,
-                                      JankType::SurfaceFlingerScheduling, DISPLAY_DEADLINE_DELTA,
-                                      DISPLAY_PRESENT_JITTER, APP_DEADLINE_DELTA_2MS});
-    mTimeStats->incrementJankyFrames({kRefreshRate0, kRenderRate0, UID_0, genLayerName(LAYER_ID_0),
-                                      TimeStatsHelper::GameModeStandard, JankType::PredictionError,
-                                      DISPLAY_DEADLINE_DELTA, DISPLAY_PRESENT_JITTER,
-                                      APP_DEADLINE_DELTA_2MS});
-    mTimeStats->incrementJankyFrames({kRefreshRate0, kRenderRate0, UID_0, genLayerName(LAYER_ID_0),
-                                      TimeStatsHelper::GameModeStandard,
-                                      JankType::AppDeadlineMissed | JankType::BufferStuffing,
-                                      DISPLAY_DEADLINE_DELTA, APP_DEADLINE_DELTA_2MS,
-                                      APP_DEADLINE_DELTA_2MS});
-    mTimeStats->incrementJankyFrames({kRefreshRate0, kRenderRate0, UID_0, genLayerName(LAYER_ID_0),
-                                      TimeStatsHelper::GameModeStandard, JankType::None,
-                                      DISPLAY_DEADLINE_DELTA, DISPLAY_PRESENT_JITTER,
-                                      APP_DEADLINE_DELTA_3MS});
 
     std::string pulledData;
     EXPECT_TRUE(mTimeStats->onPullAtom(10063 /*SURFACEFLINGER_STATS_LAYER_INFO*/, &pulledData));
@@ -1293,22 +1289,18 @@
     constexpr size_t BAD_DESIRED_PRESENT_FRAMES = 3;
     EXPECT_TRUE(inputCommand(InputCommand::ENABLE, FMT_STRING).empty());
 
-    insertTimeRecord(NORMAL_SEQUENCE, LAYER_ID_0, 1, 1000000, {},
-                     TimeStatsHelper::GameModeStandard);
+    insertTimeRecord(NORMAL_SEQUENCE, LAYER_ID_0, 1, 1000000, {}, GameMode::Standard);
     for (size_t i = 0; i < LATE_ACQUIRE_FRAMES; i++) {
         mTimeStats->incrementLatchSkipped(LAYER_ID_0, TimeStats::LatchSkipReason::LateAcquire);
     }
     for (size_t i = 0; i < BAD_DESIRED_PRESENT_FRAMES; i++) {
         mTimeStats->incrementBadDesiredPresent(LAYER_ID_0);
     }
-    insertTimeRecord(NORMAL_SEQUENCE, LAYER_ID_0, 2, 2000000, {},
-                     TimeStatsHelper::GameModeStandard);
 
-    insertTimeRecord(NORMAL_SEQUENCE, LAYER_ID_0, 3, 3000000, {},
-                     TimeStatsHelper::GameModePerformance);
-
-    insertTimeRecord(NORMAL_SEQUENCE, LAYER_ID_0, 4, 4000000, {}, TimeStatsHelper::GameModeBattery);
-    insertTimeRecord(NORMAL_SEQUENCE, LAYER_ID_0, 5, 4000000, {}, TimeStatsHelper::GameModeBattery);
+    insertTimeRecord(NORMAL_SEQUENCE, LAYER_ID_0, 2, 2000000, {}, GameMode::Standard);
+    insertTimeRecord(NORMAL_SEQUENCE, LAYER_ID_0, 3, 3000000, {}, GameMode::Performance);
+    insertTimeRecord(NORMAL_SEQUENCE, LAYER_ID_0, 4, 4000000, {}, GameMode::Battery);
+    insertTimeRecord(NORMAL_SEQUENCE, LAYER_ID_0, 5, 4000000, {}, GameMode::Battery);
 
     std::string pulledData;
     EXPECT_TRUE(mTimeStats->onPullAtom(10063 /*SURFACEFLINGER_STATS_LAYER_INFO*/, &pulledData));
diff --git a/services/surfaceflinger/tests/unittests/mock/MockTimeStats.h b/services/surfaceflinger/tests/unittests/mock/MockTimeStats.h
index 5aebd2f..0a69b56 100644
--- a/services/surfaceflinger/tests/unittests/mock/MockTimeStats.h
+++ b/services/surfaceflinger/tests/unittests/mock/MockTimeStats.h
@@ -41,19 +41,21 @@
     MOCK_METHOD2(recordFrameDuration, void(nsecs_t, nsecs_t));
     MOCK_METHOD2(recordRenderEngineDuration, void(nsecs_t, nsecs_t));
     MOCK_METHOD2(recordRenderEngineDuration, void(nsecs_t, const std::shared_ptr<FenceTime>&));
-    MOCK_METHOD6(setPostTime, void(int32_t, uint64_t, const std::string&, uid_t, nsecs_t, int32_t));
+    MOCK_METHOD(void, setPostTime,
+                (int32_t, uint64_t, const std::string&, uid_t, nsecs_t, GameMode), (override));
     MOCK_METHOD2(incrementLatchSkipped, void(int32_t layerId, LatchSkipReason reason));
     MOCK_METHOD1(incrementBadDesiredPresent, void(int32_t layerId));
     MOCK_METHOD3(setLatchTime, void(int32_t, uint64_t, nsecs_t));
     MOCK_METHOD3(setDesiredTime, void(int32_t, uint64_t, nsecs_t));
     MOCK_METHOD3(setAcquireTime, void(int32_t, uint64_t, nsecs_t));
     MOCK_METHOD3(setAcquireFence, void(int32_t, uint64_t, const std::shared_ptr<FenceTime>&));
-    MOCK_METHOD7(setPresentTime,
-                 void(int32_t, uint64_t, nsecs_t, Fps, std::optional<Fps>, SetFrameRateVote,
-                      int32_t));
-    MOCK_METHOD7(setPresentFence,
-                 void(int32_t, uint64_t, const std::shared_ptr<FenceTime>&, Fps, std::optional<Fps>,
-                      SetFrameRateVote, int32_t));
+    MOCK_METHOD(void, setPresentTime,
+                (int32_t, uint64_t, nsecs_t, Fps, std::optional<Fps>, SetFrameRateVote, GameMode),
+                (override));
+    MOCK_METHOD(void, setPresentFence,
+                (int32_t, uint64_t, const std::shared_ptr<FenceTime>&, Fps, std::optional<Fps>,
+                 SetFrameRateVote, GameMode),
+                (override));
     MOCK_METHOD1(incrementJankyFrames, void(const JankyFramesInfo&));
     MOCK_METHOD1(onDestroy, void(int32_t));
     MOCK_METHOD2(removeTimeRecord, void(int32_t, uint64_t));