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linux/arch/s390/include/asm/timex.h
Heiko Carstens 545b288dcb [S390] time: let local_tick_enable/disable() reprogram the clock comparator
Let local_tick_enable/disable() reprogram the clock comparator so the
function names make semantically more sense.
Also that way the functions are more symmetric since normally each
local_tick_enable() call usually would have a subsequent call to
set_clock_comparator() anyway.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-01-05 12:47:25 +01:00

130 lines
2.7 KiB
C

/*
* include/asm-s390/timex.h
*
* S390 version
* Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
*
* 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;
asm volatile("stck %0" : "=Q" (clk) : : "cc");
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;
/**
* get_clock_monotonic - returns current time in clock rate units
*
* The caller must ensure that preemption is disabled.
* The clock and sched_clock_base get changed via stop_machine.
* Therefore preemption must be disabled when calling this
* function, otherwise the returned value is not guaranteed to
* be monotonic.
*/
static inline unsigned long long get_clock_monotonic(void)
{
return get_clock_xt() - sched_clock_base_cc;
}
#endif