SF: Revamp frequencyScale backdoor

Update the frequencyScale backdoor (1029) to do a primary
display hot unplug-plug so that the updated frequency makes
it to the DisplayManager

Test: adb shell service call SurfaceFlinger 1029 i32 2 i32 3
Change-Id: Id93a5946ee19fbe9925789ba3294cbf213a52c30
diff --git a/services/surfaceflinger/DisplayHardware/HWC2.cpp b/services/surfaceflinger/DisplayHardware/HWC2.cpp
index ef31908..a32ff6e 100644
--- a/services/surfaceflinger/DisplayHardware/HWC2.cpp
+++ b/services/surfaceflinger/DisplayHardware/HWC2.cpp
@@ -184,6 +184,7 @@
 
         auto newDisplay = std::make_unique<Display>(
                 *mComposer.get(), mPowerAdvisor, mCapabilities, displayId, displayType);
+        newDisplay->setFrequencyScaleParameters(mFrequencyScaler);
         newDisplay->setConnected(true);
         mDisplays.emplace(displayId, std::move(newDisplay));
     } else if (connection == Connection::Disconnected) {
@@ -223,6 +224,14 @@
     return static_cast<Error>(mComposer->executeCommands());
 }
 
+void Device::setDisplayFrequencyScaleParameters(Device::FrequencyScaler frequencyScaler) {
+    mFrequencyScaler = frequencyScaler;
+}
+
+Device::FrequencyScaler Device::getDisplayFrequencyScaleParameters() {
+    return mFrequencyScaler;
+}
+
 // Display methods
 
 Display::Display(android::Hwc2::Composer& composer, android::Hwc2::PowerAdvisor& advisor,
@@ -262,6 +271,7 @@
     mWidth(-1),
     mHeight(-1),
     mVsyncPeriod(-1),
+    mFrequencyScaler(display.mFrequencyScaler),
     mDpiX(-1),
     mDpiY(-1) {}
 
@@ -701,6 +711,10 @@
     mIsConnected = connected;
 }
 
+void Display::setFrequencyScaleParameters(Device::FrequencyScaler frequencyScaler) {
+    mFrequencyScaler = frequencyScaler;
+}
+
 int32_t Display::getAttribute(hwc2_config_t configId, Attribute attribute)
 {
     int32_t value = 0;
diff --git a/services/surfaceflinger/DisplayHardware/HWC2.h b/services/surfaceflinger/DisplayHardware/HWC2.h
index e0d6ecc..a8f24d6 100644
--- a/services/surfaceflinger/DisplayHardware/HWC2.h
+++ b/services/surfaceflinger/DisplayHardware/HWC2.h
@@ -85,6 +85,11 @@
 public:
     explicit Device(std::unique_ptr<android::Hwc2::Composer> composer);
 
+    struct FrequencyScaler {
+        int32_t multiplier = 1;
+        int32_t divisor = 1;
+    };
+
     void registerCallback(ComposerCallback* callback, int32_t sequenceId);
 
     // Required by HWC2
@@ -116,6 +121,9 @@
     // This method provides an explicit way to flush state changes to HWC.
     Error flushCommands();
 
+    void setDisplayFrequencyScaleParameters(FrequencyScaler frequecyScaler);
+    FrequencyScaler getDisplayFrequencyScaleParameters();
+
 private:
     // Initialization methods
 
@@ -126,6 +134,7 @@
     std::unordered_set<Capability> mCapabilities;
     std::unordered_map<hwc2_display_t, std::unique_ptr<Display>> mDisplays;
     android::Hwc2::impl::PowerAdvisor mPowerAdvisor;
+    FrequencyScaler mFrequencyScaler;
     bool mRegisteredCallback = false;
 };
 
@@ -161,8 +170,6 @@
             }
             Builder& setVsyncPeriod(int32_t vsyncPeriod) {
                 mConfig->mVsyncPeriod = vsyncPeriod;
-                mConfig->mPeriodMultiplier = 1;
-                mConfig->mPeriodDivisor = 1;
                 return *this;
             }
             Builder& setDpiX(int32_t dpiX) {
@@ -193,11 +200,7 @@
         int32_t getWidth() const { return mWidth; }
         int32_t getHeight() const { return mHeight; }
         nsecs_t getVsyncPeriod() const {
-            return mVsyncPeriod * mPeriodMultiplier / mPeriodDivisor; }
-        void scalePanelFrequency(int32_t multiplier, int32_t divisor) const {
-            mPeriodMultiplier = multiplier;
-            mPeriodDivisor = divisor;
-        }
+            return mVsyncPeriod * mFrequencyScaler.multiplier / mFrequencyScaler.divisor; }
         float getDpiX() const { return mDpiX; }
         float getDpiY() const { return mDpiY; }
 
@@ -210,8 +213,7 @@
         int32_t mWidth;
         int32_t mHeight;
         nsecs_t mVsyncPeriod;
-        mutable int32_t mPeriodMultiplier;
-        mutable int32_t mPeriodDivisor;
+        Device::FrequencyScaler mFrequencyScaler;
         float mDpiX;
         float mDpiY;
     };
@@ -279,6 +281,7 @@
     hwc2_display_t getId() const { return mId; }
     bool isConnected() const { return mIsConnected; }
     void setConnected(bool connected);  // For use by Device only
+    void setFrequencyScaleParameters(Device::FrequencyScaler frequencyScaler);
 
 private:
     int32_t getAttribute(hwc2_config_t configId, Attribute attribute);
@@ -303,6 +306,7 @@
     hwc2_display_t mId;
     bool mIsConnected;
     DisplayType mType;
+    Device::FrequencyScaler mFrequencyScaler;
     std::unordered_map<hwc2_layer_t, std::unique_ptr<Layer>> mLayers;
     std::unordered_map<hwc2_config_t, std::shared_ptr<const Config>> mConfigs;
 };
diff --git a/services/surfaceflinger/DisplayHardware/HWComposer.cpp b/services/surfaceflinger/DisplayHardware/HWComposer.cpp
index bf8905a..630cc0b 100644
--- a/services/surfaceflinger/DisplayHardware/HWComposer.cpp
+++ b/services/surfaceflinger/DisplayHardware/HWComposer.cpp
@@ -807,4 +807,15 @@
     return mDisplayData[displayId].hwcDisplay->getId();
 }
 
+void HWComposer::setDisplayFrequencyScaleParameters(
+        HWC2::Device::FrequencyScaler frequencyScaler)
+{
+    mHwcDevice->setDisplayFrequencyScaleParameters(frequencyScaler);
+}
+
+HWC2::Device::FrequencyScaler HWComposer::getDisplayFrequencyScaleParameters()
+{
+    return mHwcDevice->getDisplayFrequencyScaleParameters();
+}
+
 } // namespace android
diff --git a/services/surfaceflinger/DisplayHardware/HWComposer.h b/services/surfaceflinger/DisplayHardware/HWComposer.h
index 3c5efea..9e01626 100644
--- a/services/surfaceflinger/DisplayHardware/HWComposer.h
+++ b/services/surfaceflinger/DisplayHardware/HWComposer.h
@@ -184,6 +184,14 @@
     android::Hwc2::Composer* getComposer() const { return mHwcDevice->getComposer(); }
 
     std::optional<hwc2_display_t> getHwcDisplayId(int32_t displayId) const;
+
+    // ------------------------------------------------------------------------
+    // These functions set and get the frequencyScaler.  The frequencyScaler holds
+    // a multiplier and divisor for virtually scaling the panel frequency in
+    // software.  This is used to simulate different panel frequencies when
+    // panel hardware is not available.
+    void setDisplayFrequencyScaleParameters(HWC2::Device::FrequencyScaler frequencyScaler);
+    HWC2::Device::FrequencyScaler getDisplayFrequencyScaleParameters();
 private:
     // For unit tests
     friend TestableSurfaceFlinger;
diff --git a/services/surfaceflinger/Scheduler/DispSync.cpp b/services/surfaceflinger/Scheduler/DispSync.cpp
index 9d9acd3..54a1b51 100644
--- a/services/surfaceflinger/Scheduler/DispSync.cpp
+++ b/services/surfaceflinger/Scheduler/DispSync.cpp
@@ -521,16 +521,18 @@
     mThread->updateModel(mPeriod, mPhase, mReferenceTime);
 }
 
-void DispSync::scalePeriod(uint32_t multiplier, uint32_t divisor) {
+void DispSync::scalePeriod(HWC2::Device::FrequencyScaler frequencyScaler) {
     Mutex::Autolock lock(mMutex);
 
     // if only 1 of the properties is updated, we will get to this
     // point "attempting" to set the scale to 1 when it is already
     // 1.  Check that special case so that we don't do a useless
     // update of the model.
-    if ((multiplier == 1) && (divisor == 1) && (mPeriod == mPeriodBase)) return;
+    if ((frequencyScaler.multiplier == 1) &&
+            (frequencyScaler.divisor == 1) &&
+            (mPeriod == mPeriodBase)) return;
 
-    mPeriod = mPeriodBase * multiplier / divisor;
+    mPeriod = mPeriodBase * frequencyScaler.multiplier / frequencyScaler.divisor;
     mThread->updateModel(mPeriod, mPhase, mReferenceTime);
 }
 
diff --git a/services/surfaceflinger/Scheduler/DispSync.h b/services/surfaceflinger/Scheduler/DispSync.h
index 183966f..b3aef2d 100644
--- a/services/surfaceflinger/Scheduler/DispSync.h
+++ b/services/surfaceflinger/Scheduler/DispSync.h
@@ -24,6 +24,7 @@
 #include <utils/Timers.h>
 
 #include <ui/FenceTime.h>
+#include <DisplayHardware/HWC2.h>
 
 #include <memory>
 
@@ -48,7 +49,7 @@
     virtual bool addResyncSample(nsecs_t timestamp) = 0;
     virtual void endResync() = 0;
     virtual void setPeriod(nsecs_t period) = 0;
-    virtual void scalePeriod(const uint32_t multiplier, uint32_t divisor) = 0;
+    virtual void scalePeriod(HWC2::Device::FrequencyScaler) = 0;
     virtual nsecs_t getPeriod() = 0;
     virtual void setRefreshSkipCount(int count) = 0;
     virtual status_t addEventListener(const char* name, nsecs_t phase, Callback* callback) = 0;
@@ -122,7 +123,7 @@
     // scale the vsync event model's period.   The function is added
     // for an experimental test mode and should not be used outside
     // of that purpose.
-    void scalePeriod(const uint32_t multiplier, uint32_t divisor);
+    void scalePeriod(HWC2::Device::FrequencyScaler frequencyScaler);
 
     // The getPeriod method returns the current vsync period.
     nsecs_t getPeriod() override;
diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index a779289..a6320a6 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -4830,27 +4830,40 @@
                 // Code 1029 is an experimental feature that allows applications to
                 // simulate a high frequency panel by setting a multiplier and divisor
                 // on the VSYNC-sf clock.  If either the multiplier or divisor are
-                // 0, then the code will set both to 1 to return the VSYNC-sf clock
-                // to it's normal frequency.
-                int multiplier = data.readInt32();
-                int divisor = data.readInt32();
+                // 0, then the code simply return the current multiplier and divisor.
+                HWC2::Device::FrequencyScaler frequencyScaler;
+                frequencyScaler.multiplier = data.readInt32();
+                frequencyScaler.divisor = data.readInt32();
 
-                if ((multiplier == 0) || (divisor == 0)) {
-                    multiplier = 1;
-                    divisor = 1;
+                if ((frequencyScaler.multiplier == 0) || (frequencyScaler.divisor == 0)) {
+                    frequencyScaler = getBE().mHwc->getDisplayFrequencyScaleParameters();
+                    reply->writeInt32(frequencyScaler.multiplier);
+                    reply->writeInt32(frequencyScaler.divisor);
+                    return NO_ERROR;
                 }
 
-                if ((multiplier == 1) && (divisor == 1)) {
+                if ((frequencyScaler.multiplier == 1) && (frequencyScaler.divisor == 1)) {
                     enableHardwareVsync();
                 } else {
                     disableHardwareVsync(true);
                 }
-                getBE().mHwc->getActiveConfig(DisplayDevice::DISPLAY_PRIMARY)
-                    ->scalePanelFrequency(multiplier, divisor);
-                mPrimaryDispSync->scalePeriod(multiplier, divisor);
+                mPrimaryDispSync->scalePeriod(frequencyScaler);
+                getBE().mHwc->setDisplayFrequencyScaleParameters(frequencyScaler);
 
-                ATRACE_INT("PeriodMultiplier", multiplier);
-                ATRACE_INT("PeriodDivisor", divisor);
+                ATRACE_INT("PeriodMultiplier", frequencyScaler.multiplier);
+                ATRACE_INT("PeriodDivisor", frequencyScaler.divisor);
+
+                const hwc2_display_t hwcDisplayId = getBE().mHwc->getActiveConfig(
+                        DisplayDevice::DISPLAY_PRIMARY)->getDisplayId();
+
+                onHotplugReceived(getBE().mComposerSequenceId,
+                        hwcDisplayId, HWC2::Connection::Disconnected);
+                onHotplugReceived(getBE().mComposerSequenceId,
+                        hwcDisplayId, HWC2::Connection::Connected);
+                frequencyScaler = getBE().mHwc->getDisplayFrequencyScaleParameters();
+                reply->writeInt32(frequencyScaler.multiplier);
+                reply->writeInt32(frequencyScaler.divisor);
+
                 return NO_ERROR;
             }
             // Is device color managed?
diff --git a/services/surfaceflinger/tests/unittests/mock/MockDispSync.h b/services/surfaceflinger/tests/unittests/mock/MockDispSync.h
index 06a6b69..46d6558 100644
--- a/services/surfaceflinger/tests/unittests/mock/MockDispSync.h
+++ b/services/surfaceflinger/tests/unittests/mock/MockDispSync.h
@@ -35,7 +35,7 @@
     MOCK_METHOD1(addResyncSample, bool(nsecs_t));
     MOCK_METHOD0(endResync, void());
     MOCK_METHOD1(setPeriod, void(nsecs_t));
-    MOCK_METHOD2(scalePeriod, void(uint32_t, uint32_t));
+    MOCK_METHOD1(scalePeriod, void(HWC2::Device::FrequencyScaler));
     MOCK_METHOD0(getPeriod, nsecs_t());
     MOCK_METHOD1(setRefreshSkipCount, void(int));
     MOCK_METHOD3(addEventListener, status_t(const char*, nsecs_t, Callback*));