linux/linux-5.4.31/arch/arm64/include/asm/vdso/gettimeofday.h

104 lines
2.1 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (C) 2018 ARM Limited
*/
#ifndef __ASM_VDSO_GETTIMEOFDAY_H
#define __ASM_VDSO_GETTIMEOFDAY_H
#ifndef __ASSEMBLY__
#include <asm/unistd.h>
#include <uapi/linux/time.h>
#define __VDSO_USE_SYSCALL ULLONG_MAX
#define VDSO_HAS_CLOCK_GETRES 1
static __always_inline
int gettimeofday_fallback(struct __kernel_old_timeval *_tv,
struct timezone *_tz)
{
register struct timezone *tz asm("x1") = _tz;
register struct __kernel_old_timeval *tv asm("x0") = _tv;
register long ret asm ("x0");
register long nr asm("x8") = __NR_gettimeofday;
asm volatile(
" svc #0\n"
: "=r" (ret)
: "r" (tv), "r" (tz), "r" (nr)
: "memory");
return ret;
}
static __always_inline
long clock_gettime_fallback(clockid_t _clkid, struct __kernel_timespec *_ts)
{
register struct __kernel_timespec *ts asm("x1") = _ts;
register clockid_t clkid asm("x0") = _clkid;
register long ret asm ("x0");
register long nr asm("x8") = __NR_clock_gettime;
asm volatile(
" svc #0\n"
: "=r" (ret)
: "r" (clkid), "r" (ts), "r" (nr)
: "memory");
return ret;
}
static __always_inline
int clock_getres_fallback(clockid_t _clkid, struct __kernel_timespec *_ts)
{
register struct __kernel_timespec *ts asm("x1") = _ts;
register clockid_t clkid asm("x0") = _clkid;
register long ret asm ("x0");
register long nr asm("x8") = __NR_clock_getres;
asm volatile(
" svc #0\n"
: "=r" (ret)
: "r" (clkid), "r" (ts), "r" (nr)
: "memory");
return ret;
}
static __always_inline u64 __arch_get_hw_counter(s32 clock_mode)
{
u64 res;
/*
* clock_mode == 0 implies that vDSO are enabled otherwise
* fallback on syscall.
*/
if (clock_mode)
return __VDSO_USE_SYSCALL;
/*
* This isb() is required to prevent that the counter value
* is speculated.
*/
isb();
asm volatile("mrs %0, cntvct_el0" : "=r" (res) :: "memory");
/*
* This isb() is required to prevent that the seq lock is
* speculated.#
*/
isb();
return res;
}
static __always_inline
const struct vdso_data *__arch_get_vdso_data(void)
{
return _vdso_data;
}
#endif /* !__ASSEMBLY__ */
#endif /* __ASM_VDSO_GETTIMEOFDAY_H */