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 /* 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 #define CLOCK_TICK_RATE 1193180 /* Underlying HZ */
  53
  54 typedef unsigned long long cycles_t;
  55
  56 static inline unsigned long long get_clock (void)
  57 {
  58         unsigned long long clk;
  59
  60         asm volatile("stck %0" : "=Q" (clk) : : "cc");
  61         return clk;
  62 }
  63
  64 static inline void get_clock_ext(char *clk)
  65 {
  66         asm volatile("stcke %0" : "=Q" (*clk) : : "cc");
  67 }
  68
  69 static inline unsigned long long get_clock_xt(void)
  70 {
  71         unsigned char clk[16];
  72         get_clock_ext(clk);
  73         return *((unsigned long long *)&clk[1]);
  74 }
  75
  76 static inline cycles_t get_cycles(void)
  77 {
  78         return (cycles_t) get_clock() >> 2;
  79 }
  80
  81 int get_sync_clock(unsigned long long *clock);
  82 void init_cpu_timer(void);
  83 unsigned long long monotonic_clock(void);
  84
  85 void tod_to_timeval(__u64, struct timespec *);
  86
  87 static inline
  88 void stck_to_timespec(unsigned long long stck, struct timespec *ts)
  89 {
  90         tod_to_timeval(stck - TOD_UNIX_EPOCH, ts);
  91 }
  92
  93 extern u64 sched_clock_base_cc;
  94
  95 /**
  96  * get_clock_monotonic - returns current time in clock rate units
  97  *
  98  * The caller must ensure that preemption is disabled.
  99  * The clock and sched_clock_base get changed via stop_machine.
 100  * Therefore preemption must be disabled when calling this
 101  * function, otherwise the returned value is not guaranteed to
 102  * be monotonic.
 103  */
 104 static inline unsigned long long get_clock_monotonic(void)
 105 {
 106         return get_clock_xt() - sched_clock_base_cc;
 107 }
 108
 109 #endif