beaglebone: initial Kconfig and Makefiles

Initial structure of Beaglebone port

Change-Id: Ia255ab207f424dcd525990cdc0d74953e012c087
Signed-off-by: David Hendricks <dhendrix@chromium.org>
Signed-off-by: Gabe Black <gabeblack@chromium.org>
Reviewed-on: http://review.coreboot.org/3279
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>

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;
+}