1 files changed, 65 insertions, 0 deletions
diff --git a/drivers/clocksource/armv8-timer.c b/drivers/clocksource/armv8-timer.c
new file mode 100644
index 0000000000..57b0b694c7
--- /dev/null
+++ b/drivers/clocksource/armv8-timer.c
@@ -0,0 +1,65 @@
+/*
+ * Copyright (C) 2018 Sascha Hauer <s.hauer@pengutronix.de>
+ *
+ * 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; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * 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.
+ *
+ */
+
+#include <common.h>
+#include <init.h>
+#include <clock.h>
+#include <linux/clk.h>
+#include <io.h>
+#include <asm/system.h>
+
+uint64_t armv8_clocksource_read(void)
+{
+	unsigned long cntpct;
+
+	isb();
+	asm volatile("mrs %0, cntpct_el0" : "=r" (cntpct));
+
+	return cntpct;
+}
+
+static struct clocksource cs = {
+	.read	= armv8_clocksource_read,
+	.mask	= CLOCKSOURCE_MASK(64),
+	.shift	= 0,
+};
+
+static int armv8_timer_probe(struct device_d *dev)
+{
+	unsigned long cntfrq;
+
+	asm volatile("mrs %0, cntfrq_el0" : "=r" (cntfrq));
+
+	cs.mult = clocksource_hz2mult(cntfrq, cs.shift);
+
+	return init_clock(&cs);
+}
+
+static struct of_device_id armv8_timer_dt_ids[] = {
+	{ .compatible = "arm,armv8-timer", },
+	{ }
+};
+
+static struct driver_d armv8_timer_driver = {
+	.name = "armv8-timer",
+	.probe = armv8_timer_probe,
+	.of_compatible = DRV_OF_COMPAT(armv8_timer_dt_ids),
+};
+
+static int armv8_timer_init(void)
+{
+	return platform_driver_register(&armv8_timer_driver);
+}
+postcore_initcall(armv8_timer_init);