1 /*
2  * Copyright (C) 2010 The Android Open Source Project
3  * Copyright (C) 2012-2014, The Linux Foundation. All rights reserved.
4  *
5  * Not a Contribution, Apache license notifications and license are
6  * retained for attribution purposes only.
7 
8  * Licensed under the Apache License, Version 2.0 (the "License");
9  * you may not use this file except in compliance with the License.
10  * You may obtain a copy of the License at
11  *
12  *      http://www.apache.org/licenses/LICENSE-2.0
13  *
14  * Unless required by applicable law or agreed to in writing, software
15  * distributed under the License is distributed on an "AS IS" BASIS,
16  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
17  * See the License for the specific language governing permissions and
18  * limitations under the License.
19  */
20 
21 #include <cutils/properties.h>
22 #include <utils/Log.h>
23 #include <fcntl.h>
24 #include <sys/ioctl.h>
25 #include <linux/msm_mdp.h>
26 #include <sys/resource.h>
27 #include <sys/prctl.h>
28 #include <poll.h>
29 #include "hwc_utils.h"
30 #include "string.h"
31 #include "external.h"
32 #include "overlay.h"
33 #define __STDC_FORMAT_MACROS 1
34 #include <inttypes.h>
35 
36 namespace qhwc {
37 
38 #define HWC_VSYNC_THREAD_NAME "hwcVsyncThread"
39 #define MAX_SYSFS_FILE_PATH             255
40 #define PANEL_ON_STR "panel_power_on ="
41 #define ARRAY_LENGTH(array) (sizeof((array))/sizeof((array)[0]))
42 const int MAX_DATA = 64;
43 
hwc_vsync_control(hwc_context_t * ctx,int dpy,int enable)44 int hwc_vsync_control(hwc_context_t* ctx, int dpy, int enable)
45 {
46     int ret = 0;
47     if(!ctx->vstate.fakevsync &&
48        ioctl(ctx->dpyAttr[dpy].fd, MSMFB_OVERLAY_VSYNC_CTRL,
49              &enable) < 0) {
50         ALOGE("%s: vsync control failed. Dpy=%d, enable=%d : %s",
51               __FUNCTION__, dpy, enable, strerror(errno));
52         ret = -errno;
53     }
54     return ret;
55 }
56 
handle_vsync_event(hwc_context_t * ctx,int dpy,char * data)57 static void handle_vsync_event(hwc_context_t* ctx, int dpy, char *data)
58 {
59     // extract timestamp
60     uint64_t timestamp = 0;
61     if (!strncmp(data, "VSYNC=", strlen("VSYNC="))) {
62         timestamp = strtoull(data + strlen("VSYNC="), NULL, 0);
63     }
64     // send timestamp to SurfaceFlinger
65     ALOGD_IF (ctx->vstate.debug, "%s: timestamp %" PRIu64 " sent to SF for dpy=%d",
66             __FUNCTION__, timestamp, dpy);
67     ctx->proc->vsync(ctx->proc, dpy, timestamp);
68 }
69 
handle_blank_event(hwc_context_t * ctx,int dpy,char * data)70 static void handle_blank_event(hwc_context_t* ctx, int dpy, char *data)
71 {
72     if (!strncmp(data, PANEL_ON_STR, strlen(PANEL_ON_STR))) {
73         unsigned long int poweron = strtoul(data + strlen(PANEL_ON_STR), NULL, 0);
74         ALOGI("%s: dpy:%d panel power state: %ld", __FUNCTION__, dpy, poweron);
75         ctx->dpyAttr[dpy].isActive = poweron ? true: false;
76     }
77 }
78 
79 struct event {
80     const char* name;
81     void (*callback)(hwc_context_t* ctx, int dpy, char *data);
82 };
83 
84 struct event event_list[] =  {
85     { "vsync_event", handle_vsync_event },
86     { "show_blank_event", handle_blank_event },
87 };
88 
89 #define num_events ARRAY_LENGTH(event_list)
90 #define VSYNC_FAILURE_THRESHOLD 2
91 
vsync_loop(void * param)92 static void *vsync_loop(void *param)
93 {
94     hwc_context_t * ctx = reinterpret_cast<hwc_context_t *>(param);
95 
96     char thread_name[64] = HWC_VSYNC_THREAD_NAME;
97     prctl(PR_SET_NAME, (unsigned long) &thread_name, 0, 0, 0);
98     setpriority(PRIO_PROCESS, 0, HAL_PRIORITY_URGENT_DISPLAY +
99                 android::PRIORITY_MORE_FAVORABLE);
100 
101     char vdata[MAX_DATA];
102     //Number of physical displays
103     //We poll on all the nodes.
104     int num_displays = HWC_NUM_DISPLAY_TYPES - 1;
105     struct pollfd pfd[num_displays][num_events];
106 
107     char property[PROPERTY_VALUE_MAX];
108     if(property_get("debug.hwc.fakevsync", property, NULL) > 0) {
109         if(atoi(property) == 1)
110             ctx->vstate.fakevsync = true;
111     }
112 
113     char node_path[MAX_SYSFS_FILE_PATH];
114 #ifdef VSYNC_FAILURE_FALLBACK
115     int fake_vsync_switch_cnt = 0;
116 #endif
117 
118     for (int dpy = HWC_DISPLAY_PRIMARY; dpy < num_displays; dpy++) {
119         for(size_t ev = 0; ev < num_events; ev++) {
120             snprintf(node_path, sizeof(node_path),
121                     "/sys/class/graphics/fb%d/%s",
122                     dpy == HWC_DISPLAY_PRIMARY ? 0 :
123                     overlay::Overlay::getInstance()->
124                     getFbForDpy(HWC_DISPLAY_EXTERNAL),
125                     event_list[ev].name);
126 
127             ALOGI("%s: Reading event %zu for dpy %d from %s", __FUNCTION__,
128                     ev, dpy, node_path);
129             pfd[dpy][ev].fd = open(node_path, O_RDONLY);
130 
131             if (dpy == HWC_DISPLAY_PRIMARY && pfd[dpy][ev].fd < 0) {
132                 // Make sure fb device is opened before starting
133                 // this thread so this never happens.
134                 ALOGE ("%s:unable to open event node for dpy=%d event=%zu, %s",
135                         __FUNCTION__, dpy, ev, strerror(errno));
136                 if (ev == 0) {
137                     ctx->vstate.fakevsync = true;
138                     //XXX: Blank events don't work with fake vsync,
139                     //but we shouldn't be running on fake vsync anyway.
140                     break;
141                 }
142             }
143 
144             pread(pfd[dpy][ev].fd, vdata , MAX_DATA, 0);
145             if (pfd[dpy][ev].fd >= 0)
146                 pfd[dpy][ev].events = POLLPRI | POLLERR;
147         }
148     }
149 
150     if (LIKELY(!ctx->vstate.fakevsync)) {
151         do {
152             int err = poll(*pfd, (int)(num_displays * num_events), -1);
153             if(err > 0) {
154                 for (int dpy = HWC_DISPLAY_PRIMARY; dpy < num_displays; dpy++) {
155                     for(size_t ev = 0; ev < num_events; ev++) {
156                         if (pfd[dpy][ev].revents & POLLPRI) {
157                             ssize_t len = pread(pfd[dpy][ev].fd, vdata, MAX_DATA, 0);
158                             if (UNLIKELY(len < 0)) {
159                                 // If the read was just interrupted - it is not
160                                 // a fatal error. Just continue in this case
161                                 ALOGE ("%s: Unable to read event:%zu for \
162                                         dpy=%d : %s",
163                                         __FUNCTION__, ev, dpy, strerror(errno));
164 #ifdef VSYNC_FAILURE_FALLBACK
165                                 fake_vsync_switch_cnt++;
166                                 if (fake_vsync_switch_cnt >
167                                         VSYNC_FAILURE_THRESHOLD) {
168                                     ALOGE("%s: Too many errors, falling back to fake vsync ",
169                                             __FUNCTION__);
170                                     ctx->vstate.fakevsync = true;
171                                     goto vsync_failed;
172                                 }
173 #endif
174                                 continue;
175                             }
176                             event_list[ev].callback(ctx, dpy, vdata);
177                         }
178                     }
179                 }
180             } else {
181                 ALOGE("%s: poll failed errno: %s", __FUNCTION__,
182                         strerror(errno));
183                 continue;
184             }
185         } while (true);
186 
187     } else {
188 
189 #ifdef VSYNC_FAILURE_FALLBACK
190 vsync_failed:
191 #endif
192         //Fake vsync is used only when set explicitly through a property or when
193         //the vsync timestamp node cannot be opened at bootup. There is no
194         //fallback to fake vsync from the true vsync loop, ever, as the
195         //condition can easily escape detection.
196         //Also, fake vsync is delivered only for the primary display.
197         do {
198             usleep(16666);
199             uint64_t timestamp = systemTime();
200             ctx->proc->vsync(ctx->proc, HWC_DISPLAY_PRIMARY, timestamp);
201 
202         } while (true);
203     }
204 
205     for (int dpy = HWC_DISPLAY_PRIMARY; dpy <= HWC_DISPLAY_EXTERNAL; dpy++ ) {
206         for( size_t event = 0; event < num_events; event++) {
207             if(pfd[dpy][event].fd >= 0)
208                 close (pfd[dpy][event].fd);
209         }
210     }
211 
212     return NULL;
213 }
214 
init_vsync_thread(hwc_context_t * ctx)215 void init_vsync_thread(hwc_context_t* ctx)
216 {
217     int ret;
218     pthread_t vsync_thread;
219     ALOGI("Initializing VSYNC Thread");
220     ret = pthread_create(&vsync_thread, NULL, vsync_loop, (void*) ctx);
221     if (ret) {
222         ALOGE("%s: failed to create %s: %s", __FUNCTION__,
223               HWC_VSYNC_THREAD_NAME, strerror(ret));
224     }
225 }
226 
227 }; //namespace
228