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   0(%2)\n"
  24                 "   ipm   %0\n"
  25                 "   srl   %0,28\n"
  26                 : "=d" (cc) : "m" (time), "a" (&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  0(%2)\n"
  36                 "   ipm   %0\n"
  37                 "   srl   %0,28\n"
  38                 : "=d" (cc), "=m" (*time) : "a" (time) : "cc");
  39         return cc;
  40 }
  41
  42 static inline void set_clock_comparator(__u64 time)
  43 {
  44         asm volatile("sckc 0(%1)" : : "m" (time), "a" (&time));
  45 }
  46
  47 static inline void store_clock_comparator(__u64 *time)
  48 {
  49         asm volatile("stckc 0(%1)" : "=m" (*time) : "a" (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 #if __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ > 2)
  61         asm volatile("stck %0" : "=Q" (clk) : : "cc");
  62 #else /* __GNUC__ */
  63         asm volatile("stck 0(%1)" : "=m" (clk) : "a" (&clk) : "cc");
  64 #endif /* __GNUC__ */
  65         return clk;
  66 }
  67
  68 static inline unsigned long long get_clock_xt(void)
  69 {
  70         unsigned char clk[16];
  71
  72 #if __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ > 2)
  73         asm volatile("stcke %0" : "=Q" (clk) : : "cc");
  74 #else /* __GNUC__ */
  75         asm volatile("stcke 0(%1)" : "=m" (clk)
  76                                    : "a" (clk) : "cc");
  77 #endif /* __GNUC__ */
  78
  79         return *((unsigned long long *)&clk[1]);
  80 }
  81
  82 static inline cycles_t get_cycles(void)
  83 {
  84         return (cycles_t) get_clock() >> 2;
  85 }
  86
  87 int get_sync_clock(unsigned long long *clock);
  88 void init_cpu_timer(void);
  89 unsigned long long monotonic_clock(void);
  90
  91 void tod_to_timeval(__u64, struct timespec *);
  92
  93 static inline
  94 void stck_to_timespec(unsigned long long stck, struct timespec *ts)
  95 {
  96         tod_to_timeval(stck - TOD_UNIX_EPOCH, ts);
  97 }
  98
  99 extern u64 sched_clock_base_cc;
 100
 101 /**
 102  * get_clock_monotonic - returns current time in clock rate units
 103  *
 104  * The caller must ensure that preemption is disabled.
 105  * The clock and sched_clock_base get changed via stop_machine.
 106  * Therefore preemption must be disabled when calling this
 107  * function, otherwise the returned value is not guaranteed to
 108  * be monotonic.
 109  */
 110 static inline unsigned long long get_clock_monotonic(void)
 111 {
 112         return get_clock_xt() - sched_clock_base_cc;
 113 }
 114
 115 #endif