arch/s390/include/asm/timex.h

   1 /*
   2  *  include/asm-s390/timex.h
   3  *
   4  *  S390 version
   5  *    Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
   6  *
   7  *  Derived from "include/asm-i386/timex.h"
   8  *    Copyright (C) 1992, Linus Torvalds
   9  */
  10
  11 #ifndef _ASM_S390_TIMEX_H
  12 #define _ASM_S390_TIMEX_H
  13
  14 #include <asm/lowcore.h>
  15
  16 /* The value of the TOD clock for 1.1.1970. */
  17 #define TOD_UNIX_EPOCH 0x7d91048bca000000ULL
  18
  19 /* Inline functions for clock register access. */
  20 static inline int set_clock(__u64 time)
  21 {
  22         int cc;
  23
  24         asm volatile(
  25                 "   sck   %1\n"
  26                 "   ipm   %0\n"
  27                 "   srl   %0,28\n"
  28                 : "=d" (cc) : "Q" (time) : "cc");
  29         return cc;
  30 }
  31
  32 static inline int store_clock(__u64 *time)
  33 {
  34         int cc;
  35
  36         asm volatile(
  37                 "   stck  %1\n"
  38                 "   ipm   %0\n"
  39                 "   srl   %0,28\n"
  40                 : "=d" (cc), "=Q" (*time) : : "cc");
  41         return cc;
  42 }
  43
  44 static inline void set_clock_comparator(__u64 time)
  45 {
  46         asm volatile("sckc %0" : : "Q" (time));
  47 }
  48
  49 static inline void store_clock_comparator(__u64 *time)
  50 {
  51         asm volatile("stckc %0" : "=Q" (*time));
  52 }
  53
  54 void clock_comparator_work(void);
  55
  56 static inline unsigned long long local_tick_disable(void)
  57 {
  58         unsigned long long old;
  59
  60         old = S390_lowcore.clock_comparator;
  61         S390_lowcore.clock_comparator = -1ULL;
  62         set_clock_comparator(S390_lowcore.clock_comparator);
  63         return old;
  64 }
  65
  66 static inline void local_tick_enable(unsigned long long comp)
  67 {
  68         S390_lowcore.clock_comparator = comp;
  69         set_clock_comparator(S390_lowcore.clock_comparator);
  70 }
  71
  72 #define CLOCK_TICK_RATE 1193180 /* Underlying HZ */
  73
  74 typedef unsigned long long cycles_t;
  75
  76 static inline unsigned long long get_clock (void)
  77 {
  78         unsigned long long clk;
  79
  80         asm volatile("stck %0" : "=Q" (clk) : : "cc");
  81         return clk;
  82 }
  83
  84 static inline void get_clock_ext(char *clk)
  85 {
  86         asm volatile("stcke %0" : "=Q" (*clk) : : "cc");
  87 }
  88
  89 static inline unsigned long long get_clock_fast(void)
  90 {
  91         unsigned long long clk;
  92
  93         if (MACHINE_HAS_STCKF)
  94                 asm volatile(".insn     s,0xb27c0000,%0" : "=Q" (clk) : : "cc");
  95         else
  96                 clk = get_clock();
  97         return clk;
  98 }
  99
 100 static inline unsigned long long get_clock_xt(void)
 101 {
 102         unsigned char clk[16];
 103         get_clock_ext(clk);
 104         return *((unsigned long long *)&clk[1]);
 105 }
 106
 107 static inline cycles_t get_cycles(void)
 108 {
 109         return (cycles_t) get_clock() >> 2;
 110 }
 111
 112 int get_sync_clock(unsigned long long *clock);
 113 void init_cpu_timer(void);
 114 unsigned long long monotonic_clock(void);
 115
 116 void tod_to_timeval(__u64, struct timespec *);
 117
 118 static inline
 119 void stck_to_timespec(unsigned long long stck, struct timespec *ts)
 120 {
 121         tod_to_timeval(stck - TOD_UNIX_EPOCH, ts);
 122 }
 123
 124 extern u64 sched_clock_base_cc;
 125
 126 /**
 127  * get_clock_monotonic - returns current time in clock rate units
 128  *
 129  * The caller must ensure that preemption is disabled.
 130  * The clock and sched_clock_base get changed via stop_machine.
 131  * Therefore preemption must be disabled when calling this
 132  * function, otherwise the returned value is not guaranteed to
 133  * be monotonic.
 134  */
 135 static inline unsigned long long get_clock_monotonic(void)
 136 {
 137         return get_clock_xt() - sched_clock_base_cc;
 138 }
 139
 140 #endif