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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/um/kernel/time.c
Initial import
Diffstat (limited to 'arch/um/kernel/time.c')
-rw-r--r--arch/um/kernel/time.c115
1 files changed, 115 insertions, 0 deletions
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;
+}