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timex.h
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1 /*
2  * S390 version
3  * Copyright IBM Corp. 1999
4  *
5  * Derived from "include/asm-i386/timex.h"
6  * Copyright (C) 1992, Linus Torvalds
7  */
8 
9 #ifndef _ASM_S390_TIMEX_H
10 #define _ASM_S390_TIMEX_H
11 
12 #include <asm/lowcore.h>
13 
14 /* The value of the TOD clock for 1.1.1970. */
15 #define TOD_UNIX_EPOCH 0x7d91048bca000000ULL
16 
17 /* Inline functions for clock register access. */
18 static inline int set_clock(__u64 time)
19 {
20  int cc;
21 
22  asm volatile(
23  " sck %1\n"
24  " ipm %0\n"
25  " srl %0,28\n"
26  : "=d" (cc) : "Q" (time) : "cc");
27  return cc;
28 }
29 
30 static inline int store_clock(__u64 *time)
31 {
32  int cc;
33 
34  asm volatile(
35  " stck %1\n"
36  " ipm %0\n"
37  " srl %0,28\n"
38  : "=d" (cc), "=Q" (*time) : : "cc");
39  return cc;
40 }
41 
42 static inline void set_clock_comparator(__u64 time)
43 {
44  asm volatile("sckc %0" : : "Q" (time));
45 }
46 
47 static inline void store_clock_comparator(__u64 *time)
48 {
49  asm volatile("stckc %0" : "=Q" (*time));
50 }
51 
52 void clock_comparator_work(void);
53 
54 static inline unsigned long long local_tick_disable(void)
55 {
56  unsigned long long old;
57 
58  old = S390_lowcore.clock_comparator;
59  S390_lowcore.clock_comparator = -1ULL;
60  set_clock_comparator(S390_lowcore.clock_comparator);
61  return old;
62 }
63 
64 static inline void local_tick_enable(unsigned long long comp)
65 {
66  S390_lowcore.clock_comparator = comp;
67  set_clock_comparator(S390_lowcore.clock_comparator);
68 }
69 
70 #define CLOCK_TICK_RATE 1193180 /* Underlying HZ */
71 
72 typedef unsigned long long cycles_t;
73 
74 static inline unsigned long long get_clock(void)
75 {
76  unsigned long long clk;
77 
78 #ifdef CONFIG_HAVE_MARCH_Z9_109_FEATURES
79  asm volatile(".insn s,0xb27c0000,%0" : "=Q" (clk) : : "cc");
80 #else
81  asm volatile("stck %0" : "=Q" (clk) : : "cc");
82 #endif
83  return clk;
84 }
85 
86 static inline void get_clock_ext(char *clk)
87 {
88  asm volatile("stcke %0" : "=Q" (*clk) : : "cc");
89 }
90 
91 static inline unsigned long long get_clock_xt(void)
92 {
93  unsigned char clk[16];
94  get_clock_ext(clk);
95  return *((unsigned long long *)&clk[1]);
96 }
97 
98 static inline cycles_t get_cycles(void)
99 {
100  return (cycles_t) get_clock() >> 2;
101 }
102 
103 int get_sync_clock(unsigned long long *clock);
104 void init_cpu_timer(void);
105 unsigned long long monotonic_clock(void);
106 
107 void tod_to_timeval(__u64, struct timespec *);
108 
109 static inline
110 void stck_to_timespec(unsigned long long stck, struct timespec *ts)
111 {
112  tod_to_timeval(stck - TOD_UNIX_EPOCH, ts);
113 }
114 
115 extern u64 sched_clock_base_cc;
116 
126 static inline unsigned long long get_clock_monotonic(void)
127 {
128  return get_clock_xt() - sched_clock_base_cc;
129 }
130 
131 #endif