/* 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/barrier.h>
#include <asm/errno.h>
#include <asm/unistd.h>
#include <asm/vdso/cp15.h>
#include <uapi/linux/time.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("r1") = _tz;
        register struct __kernel_old_timeval *tv asm("r0") = _tv;
        register long ret asm ("r0");
        register long nr asm("r7") = __NR_gettimeofday;

        asm volatile(
        "       swi #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("r1") = _ts;
        register clockid_t clkid asm("r0") = _clkid;
        register long ret asm ("r0");
        register long nr asm("r7") = __NR_clock_gettime64;

        asm volatile(
        "       swi #0\n"
        : "=r" (ret)
        : "r" (clkid), "r" (ts), "r" (nr)
        : "memory");

        return ret;
}

static __always_inline long clock_gettime32_fallback(
                                        clockid_t _clkid,
                                        struct old_timespec32 *_ts)
{
        register struct old_timespec32 *ts asm("r1") = _ts;
        register clockid_t clkid asm("r0") = _clkid;
        register long ret asm ("r0");
        register long nr asm("r7") = __NR_clock_gettime;

        asm volatile(
        "       swi #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("r1") = _ts;
        register clockid_t clkid asm("r0") = _clkid;
        register long ret asm ("r0");
        register long nr asm("r7") = __NR_clock_getres_time64;

        asm volatile(
        "       swi #0\n"
        : "=r" (ret)
        : "r" (clkid), "r" (ts), "r" (nr)
        : "memory");

        return ret;
}

static __always_inline int clock_getres32_fallback(
                                        clockid_t _clkid,
                                        struct old_timespec32 *_ts)
{
        register struct old_timespec32 *ts asm("r1") = _ts;
        register clockid_t clkid asm("r0") = _clkid;
        register long ret asm ("r0");
        register long nr asm("r7") = __NR_clock_getres;

        asm volatile(
        "       swi #0\n"
        : "=r" (ret)
        : "r" (clkid), "r" (ts), "r" (nr)
        : "memory");

        return ret;
}

static inline bool arm_vdso_hres_capable(void)
{
        return IS_ENABLED(CONFIG_ARM_ARCH_TIMER);
}
#define __arch_vdso_hres_capable arm_vdso_hres_capable

static __always_inline u64 __arch_get_hw_counter(int clock_mode,
                                                 const struct vdso_time_data *vd)
{
#ifdef CONFIG_ARM_ARCH_TIMER
        u64 cycle_now;

        /*
         * 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;

        isb();
        cycle_now = read_sysreg(CNTVCT);

        return cycle_now;
#else
        /* Make GCC happy. This is compiled out anyway */
        return 0;
#endif
}

#endif /* !__ASSEMBLY__ */

#endif /* __ASM_VDSO_GETTIMEOFDAY_H */