--- zzzz-none-000/linux-3.10.107/arch/um/kernel/time.c	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/arch/um/kernel/time.c	2021-02-04 17:41:59.000000000 +0000
@@ -1,4 +1,7 @@
 /*
+ * 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
  */
@@ -7,11 +10,15 @@
 #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)
 {
@@ -22,87 +29,99 @@
 	local_irq_restore(flags);
 }
 
-static void itimer_set_mode(enum clock_event_mode mode,
-			    struct clock_event_device *evt)
+static int itimer_shutdown(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;
+	os_timer_disable();
+	return 0;
+}
 
-	case CLOCK_EVT_MODE_RESUME:
-		break;
-	}
+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 timer_one_shot(delta + 1);
+	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 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 struct clock_event_device timer_clockevent = {
+	.name			= "posix-timer",
+	.rating			= 250,
+	.cpumask		= cpu_all_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,
+	.min_delta_ns		= 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)
 {
-	(*itimer_clockevent.event_handler)(&itimer_clockevent);
+	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 cycle_t itimer_read(struct clocksource *cs)
+static cycle_t timer_read(struct clocksource *cs)
 {
-	return os_nsecs() / 1000;
+	return os_nsecs() / TIMER_MULTIPLIER;
 }
 
-static struct clocksource itimer_clocksource = {
-	.name		= "itimer",
+static struct clocksource timer_clocksource = {
+	.name		= "timer",
 	.rating		= 300,
-	.read		= itimer_read,
+	.read		= timer_read,
 	.mask		= CLOCKSOURCE_MASK(64),
 	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
 };
 
-static void __init setup_itimer(void)
+static void __init timer_setup(void)
 {
 	int err;
 
-	err = request_irq(TIMER_IRQ, um_timer, 0, "timer", NULL);
+	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);
 
-	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);
+	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(&itimer_clockevent);
+	clockevents_register_device(&timer_clockevent);
 }
 
 void read_persistent_clock(struct timespec *ts)
 {
-	long long nsecs = os_nsecs();
+	long long nsecs = os_persistent_clock_emulation();
 
 	set_normalized_timespec(ts, nsecs / NSEC_PER_SEC,
 				nsecs % NSEC_PER_SEC);
@@ -110,6 +129,6 @@
 
 void __init time_init(void)
 {
-	timer_init();
-	late_time_init = setup_itimer;
+	timer_set_signal_handler();
+	late_time_init = timer_setup;
 }