aboutsummaryrefslogtreecommitdiff
path: root/src/cpu/ti/am335x/monotonic_timer.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/cpu/ti/am335x/monotonic_timer.c')
-rw-r--r--src/cpu/ti/am335x/monotonic_timer.c57
1 files changed, 57 insertions, 0 deletions
diff --git a/src/cpu/ti/am335x/monotonic_timer.c b/src/cpu/ti/am335x/monotonic_timer.c
new file mode 100644
index 0000000000..9a9083cd70
--- /dev/null
+++ b/src/cpu/ti/am335x/monotonic_timer.c
@@ -0,0 +1,57 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2013 Google, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <stdint.h>
+#include <delay.h>
+#include <timer.h>
+
+#include "dmtimer.h"
+
+static struct monotonic_counter {
+ int initialized;
+ struct mono_time time;
+ uint64_t last_value;
+} mono_counter;
+
+static const uint32_t clocks_per_usec = OSC_HZ/1000000;
+
+void timer_monotonic_get(struct mono_time *mt)
+{
+ uint64_t current_tick;
+ uint64_t usecs_elapsed;
+
+ if (!mono_counter.initialized) {
+ init_timer();
+ mono_counter.last_value = dmtimer_raw_value(0);
+ mono_counter.initialized = 1;
+ }
+
+ current_tick = dmtimer_raw_value(0);
+ usecs_elapsed = (current_tick - mono_counter.last_value) /
+ clocks_per_usec;
+
+ /* Update current time and tick values only if a full tick occurred. */
+ if (usecs_elapsed) {
+ mono_time_add_usecs(&mono_counter.time, usecs_elapsed);
+ mono_counter.last_value = current_tick;
+ }
+
+ /* Save result. */
+ *mt = mono_counter.time;
+}