1 files changed, 69 insertions, 0 deletions

diff --git a/drivers/clocksource/dummy_timer.c b/drivers/clocksource/dummy_timer.c
new file mode 100644
index 000000000000..1f55f9620338
--- /dev/null
+++ b/drivers/clocksource/dummy_timer.c
@@ -0,0 +1,69 @@
+/*
+ *  linux/drivers/clocksource/dummy_timer.c
+ *
+ *  Copyright (C) 2013 ARM Ltd.
+ *  All Rights Reserved
+ *
+ * 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.
+ */
+#include <linux/clockchips.h>
+#include <linux/cpu.h>
+#include <linux/init.h>
+#include <linux/percpu.h>
+#include <linux/cpumask.h>
+
+static DEFINE_PER_CPU(struct clock_event_device, dummy_timer_evt);
+
+static void dummy_timer_set_mode(enum clock_event_mode mode,
+                           struct clock_event_device *evt)
+{
+        /*
+         * Core clockevents code will call this when exchanging timer devices.
+         * We don't need to do anything here.
+         */
+}
+
+static void __cpuinit dummy_timer_setup(void)
+{
+        int cpu = smp_processor_id();
+        struct clock_event_device *evt = __this_cpu_ptr(&dummy_timer_evt);
+
+        evt->name       = "dummy_timer";
+        evt->features   = CLOCK_EVT_FEAT_PERIODIC |
+                          CLOCK_EVT_FEAT_ONESHOT |
+                          CLOCK_EVT_FEAT_DUMMY;
+        evt->rating     = 100;
+        evt->set_mode   = dummy_timer_set_mode;
+        evt->cpumask    = cpumask_of(cpu);
+
+        clockevents_register_device(evt);
+}
+
+static int __cpuinit dummy_timer_cpu_notify(struct notifier_block *self,
+                                      unsigned long action, void *hcpu)
+{
+        if ((action & ~CPU_TASKS_FROZEN) == CPU_STARTING)
+                dummy_timer_setup();
+
+        return NOTIFY_OK;
+}
+
+static struct notifier_block dummy_timer_cpu_nb __cpuinitdata = {
+        .notifier_call = dummy_timer_cpu_notify,
+};
+
+static int __init dummy_timer_register(void)
+{
+        int err = register_cpu_notifier(&dummy_timer_cpu_nb);
+        if (err)
+                return err;
+
+        /* We won't get a call on the boot CPU, so register immediately */
+        if (num_possible_cpus() > 1)
+                dummy_timer_setup();
+
+        return 0;
+}
+early_initcall(dummy_timer_register);