root/arch/arm64/include/asm/vdso/gettimeofday.h
/* SPDX-License-Identifier: GPL-2.0 */
/*
 * Copyright (C) 2018 ARM Limited
 */
#ifndef __ASM_VDSO_GETTIMEOFDAY_H
#define __ASM_VDSO_GETTIMEOFDAY_H

#ifdef __aarch64__

#ifndef __ASSEMBLER__

#include <asm/alternative.h>
#include <asm/arch_timer.h>
#include <asm/barrier.h>
#include <asm/unistd.h>
#include <asm/sysreg.h>

#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,
                                                 const struct vdso_time_data *vd)
{
        /*
         * Core checks for mode already, so this raced against a concurrent
         * update. Return something. Core will do another round and then
         * see the mode change and fallback to the syscall.
         */
        if (clock_mode == VDSO_CLOCKMODE_NONE)
                return 0;

        return __arch_counter_get_cntvct();
}

#if IS_ENABLED(CONFIG_CC_IS_GCC) && IS_ENABLED(CONFIG_PAGE_SIZE_64KB)
static __always_inline const struct vdso_time_data *__arch_get_vdso_u_time_data(void)
{
        const struct vdso_time_data *ret = &vdso_u_time_data;

        /* Work around invalid absolute relocations */
        OPTIMIZER_HIDE_VAR(ret);

        return ret;
}
#define __arch_get_vdso_u_time_data __arch_get_vdso_u_time_data
#endif /* IS_ENABLED(CONFIG_CC_IS_GCC) && IS_ENABLED(CONFIG_PAGE_SIZE_64KB) */

#endif /* !__ASSEMBLER__ */

#else /* !__aarch64__ */

#include "compat_gettimeofday.h"

#endif /* __aarch64__ */

#endif /* __ASM_VDSO_GETTIMEOFDAY_H */