timex.h

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/*
 *  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_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_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 */

typedef unsigned long long cycles_t;

static inline unsigned long long get_clock(void)
{
    unsigned long long clk;

#ifdef CONFIG_HAVE_MARCH_Z9_109_FEATURES
    asm volatile(".insn s,0xb27c0000,%0" : "=Q" (clk) : : "cc");
#else
    asm volatile("stck %0" : "=Q" (clk) : : "cc");
#endif
    return clk;
}

static inline void get_clock_ext(char *clk)
{
    asm volatile("stcke %0" : "=Q" (*clk) : : "cc");
}

static inline unsigned long long get_clock_xt(void)
{
    unsigned char clk[16];
    get_clock_ext(clk);
    return *((unsigned long long *)&clk[1]);
}

static inline cycles_t get_cycles(void)
{
    return (cycles_t) get_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;

static inline unsigned long long get_clock_monotonic(void)
{
    return get_clock_xt() - sched_clock_base_cc;
}

#endif