xref: /OK3568_Linux_fs/kernel/arch/um/os-Linux/time.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  * Copyright (C) 2015 Anton Ivanov (aivanov@{brocade.com,kot-begemot.co.uk})
4*4882a593Smuzhiyun  * Copyright (C) 2015 Thomas Meyer (thomas@m3y3r.de)
5*4882a593Smuzhiyun  * Copyright (C) 2012-2014 Cisco Systems
6*4882a593Smuzhiyun  * Copyright (C) 2000 - 2007 Jeff Dike (jdike{addtoit,linux.intel}.com)
7*4882a593Smuzhiyun  */
8*4882a593Smuzhiyun 
9*4882a593Smuzhiyun #include <stddef.h>
10*4882a593Smuzhiyun #include <errno.h>
11*4882a593Smuzhiyun #include <signal.h>
12*4882a593Smuzhiyun #include <time.h>
13*4882a593Smuzhiyun #include <sys/time.h>
14*4882a593Smuzhiyun #include <kern_util.h>
15*4882a593Smuzhiyun #include <os.h>
16*4882a593Smuzhiyun #include <string.h>
17*4882a593Smuzhiyun 
18*4882a593Smuzhiyun static timer_t event_high_res_timer = 0;
19*4882a593Smuzhiyun 
timeval_to_ns(const struct timeval * tv)20*4882a593Smuzhiyun static inline long long timeval_to_ns(const struct timeval *tv)
21*4882a593Smuzhiyun {
22*4882a593Smuzhiyun 	return ((long long) tv->tv_sec * UM_NSEC_PER_SEC) +
23*4882a593Smuzhiyun 		tv->tv_usec * UM_NSEC_PER_USEC;
24*4882a593Smuzhiyun }
25*4882a593Smuzhiyun 
timespec_to_ns(const struct timespec * ts)26*4882a593Smuzhiyun static inline long long timespec_to_ns(const struct timespec *ts)
27*4882a593Smuzhiyun {
28*4882a593Smuzhiyun 	return ((long long) ts->tv_sec * UM_NSEC_PER_SEC) + ts->tv_nsec;
29*4882a593Smuzhiyun }
30*4882a593Smuzhiyun 
os_persistent_clock_emulation(void)31*4882a593Smuzhiyun long long os_persistent_clock_emulation(void)
32*4882a593Smuzhiyun {
33*4882a593Smuzhiyun 	struct timespec realtime_tp;
34*4882a593Smuzhiyun 
35*4882a593Smuzhiyun 	clock_gettime(CLOCK_REALTIME, &realtime_tp);
36*4882a593Smuzhiyun 	return timespec_to_ns(&realtime_tp);
37*4882a593Smuzhiyun }
38*4882a593Smuzhiyun 
39*4882a593Smuzhiyun /**
40*4882a593Smuzhiyun  * os_timer_create() - create an new posix (interval) timer
41*4882a593Smuzhiyun  */
os_timer_create(void)42*4882a593Smuzhiyun int os_timer_create(void)
43*4882a593Smuzhiyun {
44*4882a593Smuzhiyun 	timer_t *t = &event_high_res_timer;
45*4882a593Smuzhiyun 
46*4882a593Smuzhiyun 	if (timer_create(CLOCK_MONOTONIC, NULL, t) == -1)
47*4882a593Smuzhiyun 		return -1;
48*4882a593Smuzhiyun 
49*4882a593Smuzhiyun 	return 0;
50*4882a593Smuzhiyun }
51*4882a593Smuzhiyun 
os_timer_set_interval(unsigned long long nsecs)52*4882a593Smuzhiyun int os_timer_set_interval(unsigned long long nsecs)
53*4882a593Smuzhiyun {
54*4882a593Smuzhiyun 	struct itimerspec its;
55*4882a593Smuzhiyun 
56*4882a593Smuzhiyun 	its.it_value.tv_sec = nsecs / UM_NSEC_PER_SEC;
57*4882a593Smuzhiyun 	its.it_value.tv_nsec = nsecs % UM_NSEC_PER_SEC;
58*4882a593Smuzhiyun 
59*4882a593Smuzhiyun 	its.it_interval.tv_sec = nsecs / UM_NSEC_PER_SEC;
60*4882a593Smuzhiyun 	its.it_interval.tv_nsec = nsecs % UM_NSEC_PER_SEC;
61*4882a593Smuzhiyun 
62*4882a593Smuzhiyun 	if (timer_settime(event_high_res_timer, 0, &its, NULL) == -1)
63*4882a593Smuzhiyun 		return -errno;
64*4882a593Smuzhiyun 
65*4882a593Smuzhiyun 	return 0;
66*4882a593Smuzhiyun }
67*4882a593Smuzhiyun 
os_timer_one_shot(unsigned long long nsecs)68*4882a593Smuzhiyun int os_timer_one_shot(unsigned long long nsecs)
69*4882a593Smuzhiyun {
70*4882a593Smuzhiyun 	struct itimerspec its = {
71*4882a593Smuzhiyun 		.it_value.tv_sec = nsecs / UM_NSEC_PER_SEC,
72*4882a593Smuzhiyun 		.it_value.tv_nsec = nsecs % UM_NSEC_PER_SEC,
73*4882a593Smuzhiyun 
74*4882a593Smuzhiyun 		.it_interval.tv_sec = 0,
75*4882a593Smuzhiyun 		.it_interval.tv_nsec = 0, // we cheat here
76*4882a593Smuzhiyun 	};
77*4882a593Smuzhiyun 
78*4882a593Smuzhiyun 	timer_settime(event_high_res_timer, 0, &its, NULL);
79*4882a593Smuzhiyun 	return 0;
80*4882a593Smuzhiyun }
81*4882a593Smuzhiyun 
82*4882a593Smuzhiyun /**
83*4882a593Smuzhiyun  * os_timer_disable() - disable the posix (interval) timer
84*4882a593Smuzhiyun  */
os_timer_disable(void)85*4882a593Smuzhiyun void os_timer_disable(void)
86*4882a593Smuzhiyun {
87*4882a593Smuzhiyun 	struct itimerspec its;
88*4882a593Smuzhiyun 
89*4882a593Smuzhiyun 	memset(&its, 0, sizeof(struct itimerspec));
90*4882a593Smuzhiyun 	timer_settime(event_high_res_timer, 0, &its, NULL);
91*4882a593Smuzhiyun }
92*4882a593Smuzhiyun 
os_nsecs(void)93*4882a593Smuzhiyun long long os_nsecs(void)
94*4882a593Smuzhiyun {
95*4882a593Smuzhiyun 	struct timespec ts;
96*4882a593Smuzhiyun 
97*4882a593Smuzhiyun 	clock_gettime(CLOCK_MONOTONIC,&ts);
98*4882a593Smuzhiyun 	return timespec_to_ns(&ts);
99*4882a593Smuzhiyun }
100*4882a593Smuzhiyun 
101*4882a593Smuzhiyun /**
102*4882a593Smuzhiyun  * os_idle_sleep() - sleep for a given time of nsecs
103*4882a593Smuzhiyun  * @nsecs: nanoseconds to sleep
104*4882a593Smuzhiyun  */
os_idle_sleep(unsigned long long nsecs)105*4882a593Smuzhiyun void os_idle_sleep(unsigned long long nsecs)
106*4882a593Smuzhiyun {
107*4882a593Smuzhiyun 	struct timespec ts = {
108*4882a593Smuzhiyun 		.tv_sec  = nsecs / UM_NSEC_PER_SEC,
109*4882a593Smuzhiyun 		.tv_nsec = nsecs % UM_NSEC_PER_SEC
110*4882a593Smuzhiyun 	};
111*4882a593Smuzhiyun 
112*4882a593Smuzhiyun 	/*
113*4882a593Smuzhiyun 	 * Relay the signal if clock_nanosleep is interrupted.
114*4882a593Smuzhiyun 	 */
115*4882a593Smuzhiyun 	if (clock_nanosleep(CLOCK_MONOTONIC, 0, &ts, NULL))
116*4882a593Smuzhiyun 		deliver_alarm();
117*4882a593Smuzhiyun }
118