1 /* 2 * Copyright 2019 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #pragma once 18 19 #include <ui/DisplayId.h> 20 #include <utils/Timers.h> 21 22 #include <scheduler/Fps.h> 23 #include <scheduler/FrameRateMode.h> 24 #include <scheduler/FrameTime.h> 25 26 #include "VSyncDispatch.h" 27 28 namespace android::scheduler { 29 30 /* 31 * VSyncTracker is an interface for providing estimates on future Vsync signal times based on 32 * historical vsync timing data. 33 */ 34 class VSyncTracker { 35 public: 36 virtual ~VSyncTracker(); 37 38 /* 39 * Adds a known timestamp from a vsync timing source (HWVsync signal, present fence) 40 * to the model. 41 * 42 * \param [in] timestamp The timestamp when the vsync signal was. 43 * \return True if the timestamp was consistent with the internal model, 44 * False otherwise 45 */ 46 virtual bool addVsyncTimestamp(nsecs_t timestamp) = 0; 47 48 /* 49 * Access the next anticipated vsync time such that the anticipated time >= timePoint. 50 * This will always give the best accurate at the time of calling; multiple 51 * calls with the same timePoint might give differing values if the internal model 52 * is updated. 53 * 54 * \param [in] timePoint The point in time after which to estimate a vsync event. 55 * \param [in] lastVsyncOpt The last vsync time used by the client. If provided, the tracker 56 * should use that as a reference point when generating the new vsync 57 * and avoid crossing the minimal frame period of a VRR display. 58 * \return A prediction of the timestamp of a vsync event. 59 */ 60 virtual nsecs_t nextAnticipatedVSyncTimeFrom(nsecs_t timePoint, 61 std::optional<nsecs_t> lastVsyncOpt = {}) = 0; 62 63 /* 64 * The current period of the vsync signal. 65 * 66 * \return The current period of the vsync signal 67 */ 68 virtual nsecs_t currentPeriod() const = 0; 69 70 /* 71 * The minimal period frames can be displayed. 72 */ 73 virtual Period minFramePeriod() const = 0; 74 75 /** 76 * Checks if the sourced mode is equal to the mode in the tracker. 77 */ 78 virtual bool isCurrentMode(const ftl::NonNull<DisplayModePtr>& modePtr) const = 0; 79 80 /* Inform the tracker that the samples it has are not accurate for prediction. */ 81 virtual void resetModel() = 0; 82 83 virtual bool needsMoreSamples() const = 0; 84 85 /* 86 * Checks if a vsync timestamp is in phase for a frame rate 87 * 88 * \param [in] timePoint A vsync timestamp 89 * \param [in] frameRate The frame rate to check for 90 */ 91 virtual bool isVSyncInPhase(nsecs_t timePoint, Fps frameRate) = 0; 92 93 /* 94 * Sets the active mode of the display which includes the vsync period and other VRR attributes. 95 * This will inform the tracker that the period is changing and the tracker needs to recalibrate 96 * itself. 97 * 98 * \param [in] DisplayModePtr The display mode the tracker will use. 99 */ 100 virtual void setDisplayModePtr(ftl::NonNull<DisplayModePtr>) = 0; 101 102 /* 103 * Sets a render rate on the tracker. If the render rate is not a divisor 104 * of the period, the render rate is ignored until the period changes. 105 * The tracker will continue to track the vsync timeline and expect it 106 * to match the current period, however, nextAnticipatedVSyncTimeFrom will 107 * return vsyncs according to the render rate set. Setting a render rate is useful 108 * when a display is running at 120Hz but the render frame rate is 60Hz. 109 * 110 * \param [in] Fps The render rate the tracker should operate at. 111 * \param [in] applyImmediately Whether to apply the new render rate immediately regardless of 112 * already committed vsyncs. 113 */ 114 virtual void setRenderRate(Fps, bool applyImmediately) = 0; 115 116 virtual void onFrameBegin(TimePoint expectedPresentTime, FrameTime lastSignaledFrameTime) = 0; 117 118 virtual void onFrameMissed(TimePoint expectedPresentTime) = 0; 119 120 virtual void dump(std::string& result) const = 0; 121 122 protected: 123 VSyncTracker(VSyncTracker const&) = delete; 124 VSyncTracker& operator=(VSyncTracker const&) = delete; 125 VSyncTracker() = default; 126 }; 127 128 } // namespace android::scheduler 129