HWComposer.h revision 3eb38cb33e41ce40dd1094bdec850f0fca9f8a53 
1/*
2 * Copyright (C) 2010 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#ifndef ANDROID_SF_HWCOMPOSER_H
18#define ANDROID_SF_HWCOMPOSER_H
19
20#include <stdint.h>
21#include <sys/types.h>
22
23#include <EGL/egl.h>
24
25#include <hardware/hwcomposer.h>
26
27#include <utils/StrongPointer.h>
28#include <utils/Vector.h>
29
30extern "C" int clock_nanosleep(clockid_t clock_id, int flags,
31                           const struct timespec *request,
32                           struct timespec *remain);
33
34namespace android {
35// ---------------------------------------------------------------------------
36
37class String8;
38class SurfaceFlinger;
39class LayerBase;
40
41class HWComposer
42{
43public:
44    class EventHandler {
45        friend class HWComposer;
46        virtual void onVSyncReceived(int dpy, nsecs_t timestamp) = 0;
47    protected:
48        virtual ~EventHandler() {}
49    };
50
51    HWComposer(const sp<SurfaceFlinger>& flinger,
52            EventHandler& handler, nsecs_t refreshPeriod);
53    ~HWComposer();
54
55    status_t initCheck() const;
56
57    // tells the HAL what the framebuffer is
58    void setFrameBuffer(EGLDisplay dpy, EGLSurface sur);
59
60    // create a work list for numLayers layer. sets HWC_GEOMETRY_CHANGED.
61    status_t createWorkList(size_t numLayers);
62
63    // Asks the HAL what it can do
64    status_t prepare() const;
65
66    // disable hwc until next createWorkList
67    status_t disable();
68
69    // commits the list
70    status_t commit() const;
71
72    // release hardware resources
73    status_t release() const;
74
75    // get the layer array created by createWorkList()
76    size_t getNumLayers() const;
77    hwc_layer_t* getLayers() const;
78
79    // get number of layers of the given type as updated in prepare().
80    // type is HWC_OVERLAY or HWC_FRAMEBUFFER
81    size_t getLayerCount(int type) const;
82
83    // Events handling ---------------------------------------------------------
84
85    enum {
86        EVENT_VSYNC = HWC_EVENT_VSYNC
87    };
88
89    status_t eventControl(int event, int enabled);
90
91    // this class is only used to fake the VSync event on systems that don't
92    // have it.
93    class VSyncThread : public Thread {
94        HWComposer& mHwc;
95        mutable Mutex mLock;
96        Condition mCondition;
97        bool mEnabled;
98        mutable nsecs_t mNextFakeVSync;
99        nsecs_t mRefreshPeriod;
100
101        virtual void onFirstRef() {
102            run("VSyncThread",
103                PRIORITY_URGENT_DISPLAY + PRIORITY_MORE_FAVORABLE);
104        }
105
106        virtual bool threadLoop() {
107            { // scope for lock
108                Mutex::Autolock _l(mLock);
109                while (!mEnabled) {
110                    mCondition.wait(mLock);
111                }
112            }
113
114            const nsecs_t period = mRefreshPeriod;
115            const nsecs_t now = systemTime(CLOCK_MONOTONIC);
116            nsecs_t next_vsync = mNextFakeVSync;
117            nsecs_t sleep = next_vsync - now;
118            if (sleep < 0) {
119                // we missed, find where the next vsync should be
120                sleep = (period - ((now - next_vsync) % period));
121                next_vsync = now + sleep;
122            }
123            mNextFakeVSync = next_vsync + period;
124
125            struct timespec spec;
126            spec.tv_sec  = next_vsync / 1000000000;
127            spec.tv_nsec = next_vsync % 1000000000;
128
129            // NOTE: EINTR can happen with clock_nanosleep(), in case of
130            // any error (including EINTR) we go through the condition's
131            // test -- this is always correct and easy.
132            if (::clock_nanosleep(CLOCK_MONOTONIC,
133                    TIMER_ABSTIME, &spec, NULL) == 0) {
134                mHwc.mEventHandler.onVSyncReceived(0, next_vsync);
135            }
136            return true;
137        }
138
139    public:
140        VSyncThread(HWComposer& hwc) :
141            mHwc(hwc), mEnabled(false),
142            mNextFakeVSync(0),
143            mRefreshPeriod(hwc.mRefreshPeriod) {
144        }
145        void setEnabled(bool enabled) {
146            Mutex::Autolock _l(mLock);
147            mEnabled = enabled;
148            mCondition.signal();
149        }
150    };
151
152    friend class VSyncThread;
153
154    // for debugging ----------------------------------------------------------
155    void dump(String8& out, char* scratch, size_t SIZE,
156            const Vector< sp<LayerBase> >& visibleLayersSortedByZ) const;
157
158private:
159
160    struct callbacks : public hwc_procs_t {
161        // these are here to facilitate the transition when adding
162        // new callbacks (an implementation can check for NULL before
163        // calling a new callback).
164        void (*zero[4])(void);
165    };
166
167    struct cb_context {
168        callbacks procs;
169        HWComposer* hwc;
170    };
171
172    static void hook_invalidate(struct hwc_procs* procs);
173    static void hook_vsync(struct hwc_procs* procs, int dpy, int64_t timestamp);
174
175    inline void invalidate();
176    inline void vsync(int dpy, int64_t timestamp);
177
178    sp<SurfaceFlinger>      mFlinger;
179    hw_module_t const*      mModule;
180    hwc_composer_device_t*  mHwc;
181    hwc_layer_list_t*       mList;
182    size_t                  mCapacity;
183    mutable size_t          mNumOVLayers;
184    mutable size_t          mNumFBLayers;
185    hwc_display_t           mDpy;
186    hwc_surface_t           mSur;
187    cb_context              mCBContext;
188    EventHandler&           mEventHandler;
189    nsecs_t                 mRefreshPeriod;
190    sp<VSyncThread>         mVSyncThread;
191};
192
193
194// ---------------------------------------------------------------------------
195}; // namespace android
196
197#endif // ANDROID_SF_HWCOMPOSER_H
198