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 #include <inttypes.h>
34 
35 namespace qhwc {
36 
37 #define HWC_VSYNC_THREAD_NAME "hwcVsyncThread"
38 #define MAX_SYSFS_FILE_PATH             255
39 #define PANEL_ON_STR "panel_power_on ="
40 #define ARRAY_LENGTH(array) (sizeof((array))/sizeof((array)[0]))
41 const int MAX_DATA = 64;
42 
hwc_vsync_control(hwc_context_t * ctx,int dpy,int enable)43 int hwc_vsync_control(hwc_context_t* ctx, int dpy, int enable)
44 {
45     int ret = 0;
46     if(!ctx->vstate.fakevsync &&
47        ioctl(ctx->dpyAttr[dpy].fd, MSMFB_OVERLAY_VSYNC_CTRL,
48              &enable) < 0) {
49         ALOGE("%s: vsync control failed. Dpy=%d, enable=%d : %s",
50               __FUNCTION__, dpy, enable, strerror(errno));
51         ret = -errno;
52     }
53     return ret;
54 }
55 
handle_vsync_event(hwc_context_t * ctx,int dpy,char * data)56 static void handle_vsync_event(hwc_context_t* ctx, int dpy, char *data)
57 {
58     // extract timestamp
59     uint64_t timestamp = 0;
60     if (!strncmp(data, "VSYNC=", strlen("VSYNC="))) {
61         timestamp = strtoull(data + strlen("VSYNC="), NULL, 0);
62     }
63     // send timestamp to SurfaceFlinger
64     ALOGD_IF (ctx->vstate.debug, "%s: timestamp %" PRIu64 " sent to SF for dpy=%d",
65             __FUNCTION__, timestamp, dpy);
66     ctx->proc->vsync(ctx->proc, dpy, timestamp);
67 }
68 
handle_blank_event(hwc_context_t * ctx,int dpy,char * data)69 static void handle_blank_event(hwc_context_t* ctx, int dpy, char *data)
70 {
71     if (!strncmp(data, PANEL_ON_STR, strlen(PANEL_ON_STR))) {
72         unsigned long int poweron = strtoul(data + strlen(PANEL_ON_STR), NULL, 0);
73         ALOGI("%s: dpy:%d panel power state: %ld", __FUNCTION__, dpy, poweron);
74         ctx->dpyAttr[dpy].isActive = poweron ? true: false;
75     }
76 }
77 
78 struct event {
79     const char* name;
80     void (*callback)(hwc_context_t* ctx, int dpy, char *data);
81 };
82 
83 struct event event_list[] =  {
84     { "vsync_event", handle_vsync_event },
85     { "show_blank_event", handle_blank_event },
86 };
87 
88 #define num_events ARRAY_LENGTH(event_list)
89 #define VSYNC_FAILURE_THRESHOLD 2
90 
vsync_loop(void * param)91 static void *vsync_loop(void *param)
92 {
93     hwc_context_t * ctx = reinterpret_cast<hwc_context_t *>(param);
94 
95     char thread_name[64] = HWC_VSYNC_THREAD_NAME;
96     prctl(PR_SET_NAME, (unsigned long) &thread_name, 0, 0, 0);
97     setpriority(PRIO_PROCESS, 0, HAL_PRIORITY_URGENT_DISPLAY +
98                 android::PRIORITY_MORE_FAVORABLE);
99 
100     char vdata[MAX_DATA];
101     //Number of physical displays
102     //We poll on all the nodes.
103     int num_displays = HWC_NUM_DISPLAY_TYPES - 1;
104     struct pollfd pfd[num_displays][num_events];
105 
106     char property[PROPERTY_VALUE_MAX];
107     if(property_get("debug.hwc.fakevsync", property, NULL) > 0) {
108         if(atoi(property) == 1)
109             ctx->vstate.fakevsync = true;
110     }
111 
112     char node_path[MAX_SYSFS_FILE_PATH];
113 #ifdef VSYNC_FAILURE_FALLBACK
114     int fake_vsync_switch_cnt = 0;
115 #endif
116 
117     for (int dpy = HWC_DISPLAY_PRIMARY; dpy < num_displays; dpy++) {
118         for(size_t ev = 0; ev < num_events; ev++) {
119             snprintf(node_path, sizeof(node_path),
120                     "/sys/class/graphics/fb%d/%s",
121                     dpy == HWC_DISPLAY_PRIMARY ? 0 :
122                     overlay::Overlay::getInstance()->
123                     getFbForDpy(HWC_DISPLAY_EXTERNAL),
124                     event_list[ev].name);
125 
126             ALOGI("%s: Reading event %zu for dpy %d from %s", __FUNCTION__,
127                     ev, dpy, node_path);
128             pfd[dpy][ev].fd = open(node_path, O_RDONLY);
129 
130             if (dpy == HWC_DISPLAY_PRIMARY && pfd[dpy][ev].fd < 0) {
131                 // Make sure fb device is opened before starting
132                 // this thread so this never happens.
133                 ALOGE ("%s:unable to open event node for dpy=%d event=%zu, %s",
134                         __FUNCTION__, dpy, ev, strerror(errno));
135                 if (ev == 0) {
136                     ctx->vstate.fakevsync = true;
137                     //XXX: Blank events don't work with fake vsync,
138                     //but we shouldn't be running on fake vsync anyway.
139                     break;
140                 }
141             }
142 
143             pread(pfd[dpy][ev].fd, vdata , MAX_DATA, 0);
144             if (pfd[dpy][ev].fd >= 0)
145                 pfd[dpy][ev].events = POLLPRI | POLLERR;
146         }
147     }
148 
149     if (LIKELY(!ctx->vstate.fakevsync)) {
150         do {
151             int err = poll(*pfd, (int)(num_displays * num_events), -1);
152             if(err > 0) {
153                 for (int dpy = HWC_DISPLAY_PRIMARY; dpy < num_displays; dpy++) {
154                     for(size_t ev = 0; ev < num_events; ev++) {
155                         if (pfd[dpy][ev].revents & POLLPRI) {
156                             ssize_t len = pread(pfd[dpy][ev].fd, vdata, MAX_DATA, 0);
157                             if (UNLIKELY(len < 0)) {
158                                 // If the read was just interrupted - it is not
159                                 // a fatal error. Just continue in this case
160                                 ALOGE ("%s: Unable to read event:%zu for \
161                                         dpy=%d : %s",
162                                         __FUNCTION__, ev, dpy, strerror(errno));
163 #ifdef VSYNC_FAILURE_FALLBACK
164                                 fake_vsync_switch_cnt++;
165                                 if (fake_vsync_switch_cnt >
166                                         VSYNC_FAILURE_THRESHOLD) {
167                                     ALOGE("%s: Too many errors, falling back to fake vsync ",
168                                             __FUNCTION__);
169                                     ctx->vstate.fakevsync = true;
170                                     goto vsync_failed;
171                                 }
172 #endif
173                                 continue;
174                             }
175                             event_list[ev].callback(ctx, dpy, vdata);
176                         }
177                     }
178                 }
179             } else {
180                 ALOGE("%s: poll failed errno: %s", __FUNCTION__,
181                         strerror(errno));
182                 continue;
183             }
184         } while (true);
185 
186     } else {
187 
188 #ifdef VSYNC_FAILURE_FALLBACK
189 vsync_failed:
190 #endif
191         //Fake vsync is used only when set explicitly through a property or when
192         //the vsync timestamp node cannot be opened at bootup. There is no
193         //fallback to fake vsync from the true vsync loop, ever, as the
194         //condition can easily escape detection.
195         //Also, fake vsync is delivered only for the primary display.
196         do {
197             usleep(16666);
198             uint64_t timestamp = systemTime();
199             ctx->proc->vsync(ctx->proc, HWC_DISPLAY_PRIMARY, timestamp);
200 
201         } while (true);
202     }
203 
204     for (int dpy = HWC_DISPLAY_PRIMARY; dpy <= HWC_DISPLAY_EXTERNAL; dpy++ ) {
205         for( size_t event = 0; event < num_events; event++) {
206             if(pfd[dpy][event].fd >= 0)
207                 close (pfd[dpy][event].fd);
208         }
209     }
210 
211     return NULL;
212 }
213 
init_vsync_thread(hwc_context_t * ctx)214 void init_vsync_thread(hwc_context_t* ctx)
215 {
216     int ret;
217     pthread_t vsync_thread;
218     ALOGI("Initializing VSYNC Thread");
219     ret = pthread_create(&vsync_thread, NULL, vsync_loop, (void*) ctx);
220     if (ret) {
221         ALOGE("%s: failed to create %s: %s", __FUNCTION__,
222               HWC_VSYNC_THREAD_NAME, strerror(ret));
223     }
224 }
225 
226 }; //namespace
227