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Diffstat (limited to 'drivers/clocksource/versatile.c')
-rw-r--r--drivers/clocksource/versatile.c40
1 files changed, 40 insertions, 0 deletions
diff --git a/drivers/clocksource/versatile.c b/drivers/clocksource/versatile.c
new file mode 100644
index 000000000000..e4c50ad2f9d9
--- /dev/null
+++ b/drivers/clocksource/versatile.c
@@ -0,0 +1,40 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * 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.
+ *
+ * Copyright (C) 2014 ARM Limited
+ */
+
+#include <linux/clocksource.h>
+#include <linux/io.h>
+#include <linux/of_address.h>
+#include <linux/sched_clock.h>
+
+#define SYS_24MHZ 0x05c
+
+static void __iomem *versatile_sys_24mhz;
+
+static u32 notrace versatile_sys_24mhz_read(void)
+{
+ return readl(versatile_sys_24mhz);
+}
+
+static void __init versatile_sched_clock_init(struct device_node *node)
+{
+ void __iomem *base = of_iomap(node, 0);
+
+ if (!base)
+ return;
+
+ versatile_sys_24mhz = base + SYS_24MHZ;
+
+ setup_sched_clock(versatile_sys_24mhz_read, 32, 24000000);
+}
+CLOCKSOURCE_OF_DECLARE(versatile, "arm,vexpress-sysreg",
+ versatile_sched_clock_init);