// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2011 Richard Weinberger <richrd@nod.at>
 * Mostly copied from arch/x86/lib/delay.c
 */

#include <linux/export.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <asm/param.h>

void __delay(unsigned long loops)
{
        asm volatile(
                "test %0,%0\n"
                "jz 3f\n"
                "jmp 1f\n"

                ".align 16\n"
                "1: jmp 2f\n"

                ".align 16\n"
                "2: dec %0\n"
                " jnz 2b\n"
                "3: dec %0\n"

                : /* we don't need output */
                : "a" (loops)
        );
}
EXPORT_SYMBOL(__delay);

inline void __const_udelay(unsigned long xloops)
{
        int d0;

        xloops *= 4;
        asm("mull %%edx"
                : "=d" (xloops), "=&a" (d0)
                : "1" (xloops), "0"
                (loops_per_jiffy * (HZ/4)));

        __delay(++xloops);
}
EXPORT_SYMBOL(__const_udelay);

void __udelay(unsigned long usecs)
{
        __const_udelay(usecs * 0x000010c7); /* 2**32 / 1000000 (rounded up) */
}
EXPORT_SYMBOL(__udelay);

void __ndelay(unsigned long nsecs)
{
        __const_udelay(nsecs * 0x00005); /* 2**32 / 1000000000 (rounded up) */
}
EXPORT_SYMBOL(__ndelay);