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 25 #include "VSyncDispatch.h" 26 27 namespace android::scheduler { 28 29 /* 30 * VSyncTracker is an interface for providing estimates on future Vsync signal times based on 31 * historical vsync timing data. 32 */ 33 class VSyncTracker { 34 public: 35 virtual ~VSyncTracker(); 36 37 /* 38 * Adds a known timestamp from a vsync timing source (HWVsync signal, present fence) 39 * to the model. 40 * 41 * \param [in] timestamp The timestamp when the vsync signal was. 42 * \return True if the timestamp was consistent with the internal model, 43 * False otherwise 44 */ 45 virtual bool addVsyncTimestamp(nsecs_t timestamp) = 0; 46 47 /* 48 * Access the next anticipated vsync time such that the anticipated time >= timePoint. 49 * This will always give the best accurate at the time of calling; multiple 50 * calls with the same timePoint might give differing values if the internal model 51 * is updated. 52 * 53 * \param [in] timePoint The point in time after which to estimate a vsync event. 54 * \param [in] lastVsyncOpt The last vsync time used by the client. If provided, the tracker 55 * should use that as a reference point when generating the new vsync 56 * and avoid crossing the minimal frame period of a VRR display. 57 * \return A prediction of the timestamp of a vsync event. 58 */ 59 virtual nsecs_t nextAnticipatedVSyncTimeFrom(nsecs_t timePoint, 60 std::optional<nsecs_t> lastVsyncOpt = {}) = 0; 61 62 /* 63 * The current period of the vsync signal. 64 * 65 * \return The current period of the vsync signal 66 */ 67 virtual nsecs_t currentPeriod() const = 0; 68 69 /* 70 * The minimal period frames can be displayed. 71 */ 72 virtual Period minFramePeriod() const = 0; 73 74 /** 75 * Checks if the sourced mode is equal to the mode in the tracker. 76 */ 77 virtual bool isCurrentMode(const ftl::NonNull<DisplayModePtr>& modePtr) const = 0; 78 79 /* Inform the tracker that the samples it has are not accurate for prediction. */ 80 virtual void resetModel() = 0; 81 82 virtual bool needsMoreSamples() const = 0; 83 84 /* 85 * Checks if a vsync timestamp is in phase for a frame rate 86 * 87 * \param [in] timePoint A vsync timestamp 88 * \param [in] frameRate The frame rate to check for 89 */ 90 virtual bool isVSyncInPhase(nsecs_t timePoint, Fps frameRate) = 0; 91 92 /* 93 * Sets the active mode of the display which includes the vsync period and other VRR attributes. 94 * This will inform the tracker that the period is changing and the tracker needs to recalibrate 95 * itself. 96 * 97 * \param [in] DisplayModePtr The display mode the tracker will use. 98 */ 99 virtual void setDisplayModePtr(ftl::NonNull<DisplayModePtr>) = 0; 100 101 /* 102 * Sets a render rate on the tracker. If the render rate is not a divisor 103 * of the period, the render rate is ignored until the period changes. 104 * The tracker will continue to track the vsync timeline and expect it 105 * to match the current period, however, nextAnticipatedVSyncTimeFrom will 106 * return vsyncs according to the render rate set. Setting a render rate is useful 107 * when a display is running at 120Hz but the render frame rate is 60Hz. 108 * 109 * \param [in] Fps The render rate the tracker should operate at. 110 * \param [in] applyImmediately Whether to apply the new render rate immediately regardless of 111 * already committed vsyncs. 112 */ 113 virtual void setRenderRate(Fps, bool applyImmediately) = 0; 114 115 virtual void onFrameBegin(TimePoint expectedPresentTime, 116 TimePoint lastConfirmedPresentTime) = 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