1/*
2 *  include/asm-s390/cputime.h
3 *
4 *  (C) Copyright IBM Corp. 2004
5 *
6 *  Author: Martin Schwidefsky <schwidefsky@de.ibm.com>
7 */
8
9#ifndef _S390_CPUTIME_H
10#define _S390_CPUTIME_H
11
12#include <linux/types.h>
13#include <linux/percpu.h>
14#include <linux/spinlock.h>
15#include <asm/div64.h>
16
17/* We want to use full resolution of the CPU timer: 2**-12 micro-seconds. */
18
19typedef unsigned long long __nocast cputime_t;
20typedef unsigned long long __nocast cputime64_t;
21
22static inline unsigned long __div(unsigned long long n, unsigned long base)
23{
24#ifndef __s390x__
25	register_pair rp;
26
27	rp.pair = n >> 1;
28	asm ("dr %0,%1" : "+d" (rp) : "d" (base >> 1));
29	return rp.subreg.odd;
30#else /* __s390x__ */
31	return n / base;
32#endif /* __s390x__ */
33}
34
35#define cputime_one_jiffy		jiffies_to_cputime(1)
36
37/*
38 * Convert cputime to jiffies and back.
39 */
40static inline unsigned long cputime_to_jiffies(const cputime_t cputime)
41{
42	return __div((__force unsigned long long) cputime, 4096000000ULL / HZ);
43}
44
45static inline cputime_t jiffies_to_cputime(const unsigned int jif)
46{
47	return (__force cputime_t)(jif * (4096000000ULL / HZ));
48}
49
50static inline u64 cputime64_to_jiffies64(cputime64_t cputime)
51{
52	unsigned long long jif = (__force unsigned long long) cputime;
53	do_div(jif, 4096000000ULL / HZ);
54	return jif;
55}
56
57static inline cputime64_t jiffies64_to_cputime64(const u64 jif)
58{
59	return (__force cputime64_t)(jif * (4096000000ULL / HZ));
60}
61
62/*
63 * Convert cputime to microseconds and back.
64 */
65static inline unsigned int cputime_to_usecs(const cputime_t cputime)
66{
67	return (__force unsigned long long) cputime >> 12;
68}
69
70static inline cputime_t usecs_to_cputime(const unsigned int m)
71{
72	return (__force cputime_t)(m * 4096ULL);
73}
74
75#define usecs_to_cputime64(m)		usecs_to_cputime(m)
76
77/*
78 * Convert cputime to milliseconds and back.
79 */
80static inline unsigned int cputime_to_secs(const cputime_t cputime)
81{
82	return __div((__force unsigned long long) cputime, 2048000000) >> 1;
83}
84
85static inline cputime_t secs_to_cputime(const unsigned int s)
86{
87	return (__force cputime_t)(s * 4096000000ULL);
88}
89
90/*
91 * Convert cputime to timespec and back.
92 */
93static inline cputime_t timespec_to_cputime(const struct timespec *value)
94{
95	unsigned long long ret = value->tv_sec * 4096000000ULL;
96	return (__force cputime_t)(ret + value->tv_nsec * 4096 / 1000);
97}
98
99static inline void cputime_to_timespec(const cputime_t cputime,
100				       struct timespec *value)
101{
102	unsigned long long __cputime = (__force unsigned long long) cputime;
103#ifndef __s390x__
104	register_pair rp;
105
106	rp.pair = __cputime >> 1;
107	asm ("dr %0,%1" : "+d" (rp) : "d" (2048000000UL));
108	value->tv_nsec = rp.subreg.even * 1000 / 4096;
109	value->tv_sec = rp.subreg.odd;
110#else
111	value->tv_nsec = (__cputime % 4096000000ULL) * 1000 / 4096;
112	value->tv_sec = __cputime / 4096000000ULL;
113#endif
114}
115
116/*
117 * Convert cputime to timeval and back.
118 * Since cputime and timeval have the same resolution (microseconds)
119 * this is easy.
120 */
121static inline cputime_t timeval_to_cputime(const struct timeval *value)
122{
123	unsigned long long ret = value->tv_sec * 4096000000ULL;
124	return (__force cputime_t)(ret + value->tv_usec * 4096ULL);
125}
126
127static inline void cputime_to_timeval(const cputime_t cputime,
128				      struct timeval *value)
129{
130	unsigned long long __cputime = (__force unsigned long long) cputime;
131#ifndef __s390x__
132	register_pair rp;
133
134	rp.pair = __cputime >> 1;
135	asm ("dr %0,%1" : "+d" (rp) : "d" (2048000000UL));
136	value->tv_usec = rp.subreg.even / 4096;
137	value->tv_sec = rp.subreg.odd;
138#else
139	value->tv_usec = (__cputime % 4096000000ULL) / 4096;
140	value->tv_sec = __cputime / 4096000000ULL;
141#endif
142}
143
144/*
145 * Convert cputime to clock and back.
146 */
147static inline clock_t cputime_to_clock_t(cputime_t cputime)
148{
149	unsigned long long clock = (__force unsigned long long) cputime;
150	do_div(clock, 4096000000ULL / USER_HZ);
151	return clock;
152}
153
154static inline cputime_t clock_t_to_cputime(unsigned long x)
155{
156	return (__force cputime_t)(x * (4096000000ULL / USER_HZ));
157}
158
159/*
160 * Convert cputime64 to clock.
161 */
162static inline clock_t cputime64_to_clock_t(cputime64_t cputime)
163{
164	unsigned long long clock = (__force unsigned long long) cputime;
165	do_div(clock, 4096000000ULL / USER_HZ);
166	return clock;
167}
168
169struct s390_idle_data {
170	unsigned int sequence;
171	unsigned long long idle_count;
172	unsigned long long idle_enter;
173	unsigned long long idle_exit;
174	unsigned long long idle_time;
175	int nohz_delay;
176};
177
178DECLARE_PER_CPU(struct s390_idle_data, s390_idle);
179
180cputime64_t s390_get_idle_time(int cpu);
181
182#define arch_idle_time(cpu) s390_get_idle_time(cpu)
183
184static inline int s390_nohz_delay(int cpu)
185{
186	return __get_cpu_var(s390_idle).nohz_delay != 0;
187}
188
189#define arch_needs_cpu(cpu) s390_nohz_delay(cpu)
190
191#endif /* _S390_CPUTIME_H */
192