1 files changed, 136 insertions, 0 deletions
diff --git a/arch/um/kernel/time.c b/arch/um/kernel/time.c
new file mode 100644
index 000000000..0c572a481
--- /dev/null
+++ b/arch/um/kernel/time.c
@@ -0,0 +1,136 @@
+/*
+ * Copyright (C) 2015 Anton Ivanov (aivanov@{brocade.com,kot-begemot.co.uk})
+ * Copyright (C) 2015 Thomas Meyer (thomas@m3y3r.de)
+ * Copyright (C) 2012-2014 Cisco Systems
+ * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
+ * Licensed under the GPL
+ */
+
+#include <linux/clockchips.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/jiffies.h>
+#include <linux/mm.h>
+#include <linux/sched.h>
+#include <linux/spinlock.h>
+#include <linux/threads.h>
+#include <asm/irq.h>
+#include <asm/param.h>
+#include <kern_util.h>
+#include <os.h>
+#include <timer-internal.h>
+
+void timer_handler(int sig, struct siginfo *unused_si, struct uml_pt_regs *regs)
+{
+	unsigned long flags;
+
+	local_irq_save(flags);
+	do_IRQ(TIMER_IRQ, regs);
+	local_irq_restore(flags);
+}
+
+static int itimer_shutdown(struct clock_event_device *evt)
+{
+	os_timer_disable();
+	return 0;
+}
+
+static int itimer_set_periodic(struct clock_event_device *evt)
+{
+	os_timer_set_interval(NULL, NULL);
+	return 0;
+}
+
+static int itimer_next_event(unsigned long delta,
+			     struct clock_event_device *evt)
+{
+	return os_timer_one_shot(delta);
+}
+
+static int itimer_one_shot(struct clock_event_device *evt)
+{
+	os_timer_one_shot(1);
+	return 0;
+}
+
+static struct clock_event_device timer_clockevent = {
+	.name			= "posix-timer",
+	.rating			= 250,
+	.cpumask		= cpu_possible_mask,
+	.features		= CLOCK_EVT_FEAT_PERIODIC |
+				  CLOCK_EVT_FEAT_ONESHOT,
+	.set_state_shutdown	= itimer_shutdown,
+	.set_state_periodic	= itimer_set_periodic,
+	.set_state_oneshot	= itimer_one_shot,
+	.set_next_event		= itimer_next_event,
+	.shift			= 0,
+	.max_delta_ns		= 0xffffffff,
+	.max_delta_ticks	= 0xffffffff,
+	.min_delta_ns		= TIMER_MIN_DELTA,
+	.min_delta_ticks	= TIMER_MIN_DELTA, // microsecond resolution should be enough for anyone, same as 640K RAM
+	.irq			= 0,
+	.mult			= 1,
+};
+
+static irqreturn_t um_timer(int irq, void *dev)
+{
+	if (get_current()->mm != NULL)
+	{
+        /* userspace - relay signal, results in correct userspace timers */
+		os_alarm_process(get_current()->mm->context.id.u.pid);
+	}
+
+	(*timer_clockevent.event_handler)(&timer_clockevent);
+
+	return IRQ_HANDLED;
+}
+
+static u64 timer_read(struct clocksource *cs)
+{
+	return os_nsecs() / TIMER_MULTIPLIER;
+}
+
+static struct clocksource timer_clocksource = {
+	.name		= "timer",
+	.rating		= 300,
+	.read		= timer_read,
+	.mask		= CLOCKSOURCE_MASK(64),
+	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+static void __init um_timer_setup(void)
+{
+	int err;
+
+	err = request_irq(TIMER_IRQ, um_timer, IRQF_TIMER, "hr timer", NULL);
+	if (err != 0)
+		printk(KERN_ERR "register_timer : request_irq failed - "
+		       "errno = %d\n", -err);
+
+	err = os_timer_create(NULL);
+	if (err != 0) {
+		printk(KERN_ERR "creation of timer failed - errno = %d\n", -err);
+		return;
+	}
+
+	err = clocksource_register_hz(&timer_clocksource, NSEC_PER_SEC/TIMER_MULTIPLIER);
+	if (err) {
+		printk(KERN_ERR "clocksource_register_hz returned %d\n", err);
+		return;
+	}
+	clockevents_register_device(&timer_clockevent);
+}
+
+void read_persistent_clock64(struct timespec64 *ts)
+{
+	long long nsecs = os_persistent_clock_emulation();
+
+	set_normalized_timespec64(ts, nsecs / NSEC_PER_SEC,
+				  nsecs % NSEC_PER_SEC);
+}
+
+void __init time_init(void)
+{
+	timer_set_signal_handler();
+	late_time_init = um_timer_setup;
+}