2 * Copyright (C) 2015 The Android Open Source Project
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
8 * http://www.apache.org/licenses/LICENSE-2.0
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.
17 #define LOG_TAG "hwc-vsync-worker"
19 #include "drmresources.h"
20 #include "vsyncworker.h"
27 #include <xf86drmMode.h>
29 #include <cutils/log.h>
30 #include <hardware/hardware.h>
34 VSyncWorker::VSyncWorker()
35 : Worker("vsync", HAL_PRIORITY_URGENT_DISPLAY),
42 VSyncWorker::~VSyncWorker() {
45 int VSyncWorker::Init(DrmResources *drm, int display) {
52 int VSyncWorker::SetProcs(hwc_procs_t const *procs) {
55 ALOGE("Failed to lock vsync worker lock %d\n", ret);
63 ALOGE("Failed to unlock vsync worker lock %d\n", ret);
69 int VSyncWorker::VSyncControl(bool enabled) {
72 ALOGE("Failed to lock vsync worker lock %d\n", ret);
78 int signal_ret = SignalLocked();
82 ALOGE("Failed to unlock vsync worker lock %d\n", ret);
90 * Returns the timestamp of the next vsync in phase with last_timestamp_.
92 * last_timestamp_ = 137
96 * ret = (50 * ((683 - 137)/50 + 1)) + 137
99 * Thus, we must sleep until timestamp 687 to maintain phase with the last
102 int64_t VSyncWorker::GetPhasedVSync(int64_t frame_ns, int64_t current) {
103 if (last_timestamp_ < 0)
104 return current + frame_ns;
106 return frame_ns * ((current - last_timestamp_) / frame_ns + 1) +
110 static const int64_t kOneSecondNs = 1 * 1000 * 1000 * 1000;
112 int VSyncWorker::SyntheticWaitVBlank(int64_t *timestamp) {
113 struct timespec vsync;
114 int ret = clock_gettime(CLOCK_MONOTONIC, &vsync);
116 int64_t refresh = 60; // Default to 60Hz refresh rate
117 DrmConnector *conn = drm_->GetConnectorForDisplay(display_);
118 if (conn && conn->active_mode().v_refresh())
119 refresh = conn->active_mode().v_refresh();
121 ALOGW("Vsync worker active with conn=%p refresh=%d\n", conn,
122 conn ? conn->active_mode().v_refresh() : -1);
124 int64_t phased_timestamp = GetPhasedVSync(
125 kOneSecondNs / refresh, vsync.tv_sec * kOneSecondNs + vsync.tv_nsec);
126 vsync.tv_sec = phased_timestamp / kOneSecondNs;
127 vsync.tv_nsec = phased_timestamp - (vsync.tv_sec * kOneSecondNs);
129 ret = clock_nanosleep(CLOCK_MONOTONIC, TIMER_ABSTIME, &vsync, NULL);
130 } while (ret == -1 && errno == EINTR);
134 *timestamp = (int64_t)vsync.tv_sec * kOneSecondNs + (int64_t)vsync.tv_nsec;
138 void VSyncWorker::Routine() {
141 ALOGE("Failed to lock worker %d", ret);
146 ret = WaitForSignalOrExitLocked();
152 bool enabled = enabled_;
153 int display = display_;
154 hwc_procs_t const *procs = procs_;
158 ALOGE("Failed to unlock worker %d", ret);
164 DrmCrtc *crtc = drm_->GetCrtcForDisplay(display);
166 ALOGE("Failed to get crtc for display");
169 uint32_t high_crtc = (crtc->pipe() << DRM_VBLANK_HIGH_CRTC_SHIFT);
172 memset(&vblank, 0, sizeof(vblank));
173 vblank.request.type = (drmVBlankSeqType)(
174 DRM_VBLANK_RELATIVE | (high_crtc & DRM_VBLANK_HIGH_CRTC_MASK));
175 vblank.request.sequence = 1;
178 ret = drmWaitVBlank(drm_->fd(), &vblank);
182 ret = SyntheticWaitVBlank(×tamp);
186 timestamp = (int64_t)vblank.reply.tval_sec * kOneSecondNs +
187 (int64_t)vblank.reply.tval_usec * 1000;
191 * There's a race here where a change in procs_ will not take effect until
192 * the next subsequent requested vsync. This is unavoidable since we can't
193 * call the vsync hook while holding the thread lock.
195 * We could shorten the race window by caching procs_ right before calling
196 * the hook. However, in practice, procs_ is only updated once, so it's not
197 * worth the overhead.
199 if (procs && procs->vsync)
200 procs->vsync(procs, display, timestamp);
201 last_timestamp_ = timestamp;