linux/arch/s390/include/asm/timex.h
Martin Schwidefsky 987bcdacb1 [S390] use inline assembly contraints available with gcc 3.3.3
Drop support to compile the kernel with gcc versions older than 3.3.3.
This allows us to use the "Q" inline assembly contraint on some more
inline assemblies without duplicating a lot of complex code (e.g. __xchg
and __cmpxchg). The distinction for older gcc versions can be removed
which saves a few lines and simplifies the code.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:30 +01:00

106 lines
2.2 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
/* 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));
}
#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 unsigned long long get_clock_xt(void)
{
unsigned char clk[16];
asm volatile("stcke %0" : "=Q" (clk) : : "cc");
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