1
2
3
4
5
6
7
8
9#include <linux/clockchips.h>
10#include <linux/init.h>
11#include <linux/interrupt.h>
12#include <linux/jiffies.h>
13#include <linux/mm.h>
14#include <linux/sched.h>
15#include <linux/spinlock.h>
16#include <linux/threads.h>
17#include <asm/irq.h>
18#include <asm/param.h>
19#include <kern_util.h>
20#include <os.h>
21#include <timer-internal.h>
22
23void timer_handler(int sig, struct siginfo *unused_si, struct uml_pt_regs *regs)
24{
25 unsigned long flags;
26
27 local_irq_save(flags);
28 do_IRQ(TIMER_IRQ, regs);
29 local_irq_restore(flags);
30}
31
32static int itimer_shutdown(struct clock_event_device *evt)
33{
34 os_timer_disable();
35 return 0;
36}
37
38static int itimer_set_periodic(struct clock_event_device *evt)
39{
40 os_timer_set_interval(NULL, NULL);
41 return 0;
42}
43
44static int itimer_next_event(unsigned long delta,
45 struct clock_event_device *evt)
46{
47 return os_timer_one_shot(delta);
48}
49
50static int itimer_one_shot(struct clock_event_device *evt)
51{
52 os_timer_one_shot(1);
53 return 0;
54}
55
56static struct clock_event_device timer_clockevent = {
57 .name = "posix-timer",
58 .rating = 250,
59 .cpumask = cpu_all_mask,
60 .features = CLOCK_EVT_FEAT_PERIODIC |
61 CLOCK_EVT_FEAT_ONESHOT,
62 .set_state_shutdown = itimer_shutdown,
63 .set_state_periodic = itimer_set_periodic,
64 .set_state_oneshot = itimer_one_shot,
65 .set_next_event = itimer_next_event,
66 .shift = 0,
67 .max_delta_ns = 0xffffffff,
68 .max_delta_ticks = 0xffffffff,
69 .min_delta_ns = TIMER_MIN_DELTA,
70 .min_delta_ticks = TIMER_MIN_DELTA,
71 .irq = 0,
72 .mult = 1,
73};
74
75static irqreturn_t um_timer(int irq, void *dev)
76{
77 if (get_current()->mm != NULL)
78 {
79
80 os_alarm_process(get_current()->mm->context.id.u.pid);
81 }
82
83 (*timer_clockevent.event_handler)(&timer_clockevent);
84
85 return IRQ_HANDLED;
86}
87
88static u64 timer_read(struct clocksource *cs)
89{
90 return os_nsecs() / TIMER_MULTIPLIER;
91}
92
93static struct clocksource timer_clocksource = {
94 .name = "timer",
95 .rating = 300,
96 .read = timer_read,
97 .mask = CLOCKSOURCE_MASK(64),
98 .flags = CLOCK_SOURCE_IS_CONTINUOUS,
99};
100
101static void __init um_timer_setup(void)
102{
103 int err;
104
105 err = request_irq(TIMER_IRQ, um_timer, IRQF_TIMER, "hr timer", NULL);
106 if (err != 0)
107 printk(KERN_ERR "register_timer : request_irq failed - "
108 "errno = %d\n", -err);
109
110 err = os_timer_create(NULL);
111 if (err != 0) {
112 printk(KERN_ERR "creation of timer failed - errno = %d\n", -err);
113 return;
114 }
115
116 err = clocksource_register_hz(&timer_clocksource, NSEC_PER_SEC/TIMER_MULTIPLIER);
117 if (err) {
118 printk(KERN_ERR "clocksource_register_hz returned %d\n", err);
119 return;
120 }
121 clockevents_register_device(&timer_clockevent);
122}
123
124void read_persistent_clock64(struct timespec64 *ts)
125{
126 long long nsecs = os_persistent_clock_emulation();
127
128 set_normalized_timespec64(ts, nsecs / NSEC_PER_SEC,
129 nsecs % NSEC_PER_SEC);
130}
131
132void __init time_init(void)
133{
134 timer_set_signal_handler();
135 late_time_init = um_timer_setup;
136}
137
