From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001
From: André Fabian Silva Delgado <emulatorman@parabola.nu>
Date: Wed, 5 Aug 2015 17:04:01 -0300
Subject: Initial import

---
 arch/um/kernel/time.c | 115 ++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 115 insertions(+)
 create mode 100644 arch/um/kernel/time.c

(limited to 'arch/um/kernel/time.c')

diff --git a/arch/um/kernel/time.c b/arch/um/kernel/time.c
new file mode 100644
index 000000000..117568d4f
--- /dev/null
+++ b/arch/um/kernel/time.c
@@ -0,0 +1,115 @@
+/*
+ * 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/threads.h>
+#include <asm/irq.h>
+#include <asm/param.h>
+#include <kern_util.h>
+#include <os.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 void itimer_set_mode(enum clock_event_mode mode,
+			    struct clock_event_device *evt)
+{
+	switch (mode) {
+	case CLOCK_EVT_MODE_PERIODIC:
+		set_interval();
+		break;
+
+	case CLOCK_EVT_MODE_SHUTDOWN:
+	case CLOCK_EVT_MODE_UNUSED:
+	case CLOCK_EVT_MODE_ONESHOT:
+		disable_timer();
+		break;
+
+	case CLOCK_EVT_MODE_RESUME:
+		break;
+	}
+}
+
+static int itimer_next_event(unsigned long delta,
+			     struct clock_event_device *evt)
+{
+	return timer_one_shot(delta + 1);
+}
+
+static struct clock_event_device itimer_clockevent = {
+	.name		= "itimer",
+	.rating		= 250,
+	.cpumask	= cpu_all_mask,
+	.features	= CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
+	.set_mode	= itimer_set_mode,
+	.set_next_event = itimer_next_event,
+	.shift		= 32,
+	.irq		= 0,
+};
+
+static irqreturn_t um_timer(int irq, void *dev)
+{
+	(*itimer_clockevent.event_handler)(&itimer_clockevent);
+
+	return IRQ_HANDLED;
+}
+
+static cycle_t itimer_read(struct clocksource *cs)
+{
+	return os_nsecs() / 1000;
+}
+
+static struct clocksource itimer_clocksource = {
+	.name		= "itimer",
+	.rating		= 300,
+	.read		= itimer_read,
+	.mask		= CLOCKSOURCE_MASK(64),
+	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+static void __init setup_itimer(void)
+{
+	int err;
+
+	err = request_irq(TIMER_IRQ, um_timer, 0, "timer", NULL);
+	if (err != 0)
+		printk(KERN_ERR "register_timer : request_irq failed - "
+		       "errno = %d\n", -err);
+
+	itimer_clockevent.mult = div_sc(HZ, NSEC_PER_SEC, 32);
+	itimer_clockevent.max_delta_ns =
+		clockevent_delta2ns(60 * HZ, &itimer_clockevent);
+	itimer_clockevent.min_delta_ns =
+		clockevent_delta2ns(1, &itimer_clockevent);
+	err = clocksource_register_hz(&itimer_clocksource, USEC_PER_SEC);
+	if (err) {
+		printk(KERN_ERR "clocksource_register_hz returned %d\n", err);
+		return;
+	}
+	clockevents_register_device(&itimer_clockevent);
+}
+
+void read_persistent_clock(struct timespec *ts)
+{
+	long long nsecs = os_nsecs();
+
+	set_normalized_timespec(ts, nsecs / NSEC_PER_SEC,
+				nsecs % NSEC_PER_SEC);
+}
+
+void __init time_init(void)
+{
+	timer_init();
+	late_time_init = setup_itimer;
+}
-- 
cgit v1.2.3-54-g00ecf