hwcomposer : Use sysfs to read vysnc information
* Read sysfs entries to get vsync timestamp from kernel.
* External display continues to use uevents for hotplug events
* A new thread, vsyncThread is created to read and send vsync
timestamps to HAL.
* Disable H/W VSYNC for MDP 5.x targets until kernel changes are
complete.
* Synchronization is needed to make sure read() is not called
by hwcVsyncThread when VSYNC is disabled.
Change-Id: Iab0a94a3cfce9142b8867859f2a7d9bcaecb0996
Acked-by: Neti Ravi Kumar <ravineti@codeaurora.org>
diff --git a/libhwcomposer/hwc_vsync.cpp b/libhwcomposer/hwc_vsync.cpp
new file mode 100644
index 0000000..cea00f4
--- /dev/null
+++ b/libhwcomposer/hwc_vsync.cpp
@@ -0,0 +1,112 @@
+/*
+ * Copyright (C) 2010 The Android Open Source Project
+ * Copyright (C) 2012, Code Aurora Forum. All rights reserved.
+ *
+ * Not a Contribution, Apache license notifications and license are
+ * retained for attribution purposes only.
+
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// WARNING : Excessive logging, if VSYNC_DEBUG enabled
+#define VSYNC_DEBUG 0
+
+#include <utils/Log.h>
+#include <fcntl.h>
+#include <sys/resource.h>
+#include <sys/prctl.h>
+#include "hwc_utils.h"
+#include "string.h"
+#include "external.h"
+
+
+namespace qhwc {
+
+static void *vsync_loop(void *param)
+{
+ const char* vsync_timestamp_fb0 = "/sys/class/graphics/fb0/vsync_event";
+ const char* vsync_timestamp_fb1 = "/sys/class/graphics/fb1/vsync_event";
+ int display = HWC_DISPLAY_PRIMARY;
+
+ hwc_context_t * ctx = reinterpret_cast<hwc_context_t *>(param);
+
+ char thread_name[64] = "hwcVsyncThread";
+ prctl(PR_SET_NAME, (unsigned long) &thread_name, 0, 0, 0);
+ setpriority(PRIO_PROCESS, 0, HAL_PRIORITY_URGENT_DISPLAY +
+ android::PRIORITY_MORE_FAVORABLE);
+
+ static char vdata[PAGE_SIZE];
+
+ uint64_t cur_timestamp=0;
+ int32_t len = -1, fd_timestamp = -1;
+ bool fb1_vsync = false;
+
+ /* Currently read vsync timestamp from drivers
+ e.g. VSYNC=41800875994
+ */
+
+ do {
+ pthread_mutex_lock(&ctx->vstate.lock);
+ if(ctx->vstate.enable == false) {
+ pthread_cond_wait(&ctx->vstate.cond, &ctx->vstate.lock);
+ }
+ pthread_mutex_unlock(&ctx->vstate.lock);
+
+
+ // try to open timestamp sysfs
+ fd_timestamp = open(vsync_timestamp_fb0, O_RDONLY);
+ if (fd_timestamp < 0) {
+ ALOGE ("FATAL:%s:not able to open file:%s, %s", __FUNCTION__,
+ (fb1_vsync) ? vsync_timestamp_fb1 : vsync_timestamp_fb0,
+ strerror(errno));
+ return NULL;
+ }
+ // Open success - read now
+ len = read(fd_timestamp, vdata, PAGE_SIZE);
+ if (len < 0){
+ ALOGE ("FATAL:%s:not able to read file:%s, %s", __FUNCTION__,
+ vsync_timestamp_fb0, strerror(errno));
+ fd_timestamp = -1;
+ return NULL;
+ }
+
+ // extract timestamp
+ const char *str = vdata;
+ if (!strncmp(str, "VSYNC=", strlen("VSYNC="))) {
+ cur_timestamp = strtoull(str + strlen("VSYNC="), NULL, 0);
+ } else {
+ ALOGE ("FATAL:%s:timestamp data not in correct format",
+ __FUNCTION__);
+ }
+ // send timestamp to HAL
+ ALOGD_IF (VSYNC_DEBUG, "%s: timestamp %llu sent to HWC for %s",
+ __FUNCTION__, cur_timestamp, "fb0");
+ ctx->proc->vsync(ctx->proc, display, cur_timestamp);
+
+ // close open fds
+ close (fd_timestamp);
+
+ // reset fd
+ fd_timestamp = -1;
+
+ } while (true);
+}
+
+void init_vsync_thread(hwc_context_t* ctx)
+{
+ pthread_t vsync_thread;
+ ALOGI("Initializing VSYNC Thread");
+ pthread_create(&vsync_thread, NULL, vsync_loop, (void*) ctx);
+}
+
+}; //namespace