blob: 98eb2a5792234d9d12c303bdb1301f869f706b60 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
|
/*
* S390 version
* Copyright IBM Corp. 1999
*
* Derived from "include/asm-i386/timex.h"
* Copyright (C) 1992, Linus Torvalds
*/
#ifndef _ASM_S390_TIMEX_H
#define _ASM_S390_TIMEX_H
#include <asm/lowcore.h>
/* The value of the TOD clock for 1.1.1970. */
#define TOD_UNIX_EPOCH 0x7d91048bca000000ULL
/* Inline functions for clock register access. */
static inline int set_tod_clock(__u64 time)
{
int cc;
asm volatile(
" sck %1\n"
" ipm %0\n"
" srl %0,28\n"
: "=d" (cc) : "Q" (time) : "cc");
return cc;
}
static inline int store_tod_clock(__u64 *time)
{
int cc;
asm volatile(
" stck %1\n"
" ipm %0\n"
" srl %0,28\n"
: "=d" (cc), "=Q" (*time) : : "cc");
return cc;
}
static inline void set_clock_comparator(__u64 time)
{
asm volatile("sckc %0" : : "Q" (time));
}
static inline void store_clock_comparator(__u64 *time)
{
asm volatile("stckc %0" : "=Q" (*time));
}
void clock_comparator_work(void);
static inline unsigned long long local_tick_disable(void)
{
unsigned long long old;
old = S390_lowcore.clock_comparator;
S390_lowcore.clock_comparator = -1ULL;
set_clock_comparator(S390_lowcore.clock_comparator);
return old;
}
static inline void local_tick_enable(unsigned long long comp)
{
S390_lowcore.clock_comparator = comp;
set_clock_comparator(S390_lowcore.clock_comparator);
}
#define CLOCK_TICK_RATE 1193180 /* Underlying HZ */
#define STORE_CLOCK_EXT_SIZE 16 /* stcke writes 16 bytes */
typedef unsigned long long cycles_t;
static inline void get_tod_clock_ext(char *clk)
{
typedef struct { char _[STORE_CLOCK_EXT_SIZE]; } addrtype;
asm volatile("stcke %0" : "=Q" (*(addrtype *) clk) : : "cc");
}
static inline unsigned long long get_tod_clock(void)
{
unsigned char clk[STORE_CLOCK_EXT_SIZE];
get_tod_clock_ext(clk);
return *((unsigned long long *)&clk[1]);
}
static inline unsigned long long get_tod_clock_fast(void)
{
#ifdef CONFIG_HAVE_MARCH_Z9_109_FEATURES
unsigned long long clk;
asm volatile("stckf %0" : "=Q" (clk) : : "cc");
return clk;
#else
return get_tod_clock();
#endif
}
static inline cycles_t get_cycles(void)
{
return (cycles_t) get_tod_clock() >> 2;
}
int get_sync_clock(unsigned long long *clock);
void init_cpu_timer(void);
unsigned long long monotonic_clock(void);
void tod_to_timeval(__u64, struct timespec *);
static inline
void stck_to_timespec(unsigned long long stck, struct timespec *ts)
{
tod_to_timeval(stck - TOD_UNIX_EPOCH, ts);
}
extern u64 sched_clock_base_cc;
/**
* get_clock_monotonic - returns current time in clock rate units
*
* The caller must ensure that preemption is disabled.
* The clock and sched_clock_base get changed via stop_machine.
* Therefore preemption must be disabled when calling this
* function, otherwise the returned value is not guaranteed to
* be monotonic.
*/
static inline unsigned long long get_tod_clock_monotonic(void)
{
return get_tod_clock() - sched_clock_base_cc;
}
/**
* tod_to_ns - convert a TOD format value to nanoseconds
* @todval: to be converted TOD format value
* Returns: number of nanoseconds that correspond to the TOD format value
*
* Converting a 64 Bit TOD format value to nanoseconds means that the value
* must be divided by 4.096. In order to achieve that we multiply with 125
* and divide by 512:
*
* ns = (todval * 125) >> 9;
*
* In order to avoid an overflow with the multiplication we can rewrite this.
* With a split todval == 2^32 * th + tl (th upper 32 bits, tl lower 32 bits)
* we end up with
*
* ns = ((2^32 * th + tl) * 125 ) >> 9;
* -> ns = (2^23 * th * 125) + ((tl * 125) >> 9);
*
*/
static inline unsigned long long tod_to_ns(unsigned long long todval)
{
unsigned long long ns;
ns = ((todval >> 32) << 23) * 125;
ns += ((todval & 0xffffffff) * 125) >> 9;
return ns;
}
#endif
|
