// SPDX-License-Identifier: GPL-2.0
/*
 *      Precise Delay Loops for SuperH
 *
 *      Copyright (C) 1999 Niibe Yutaka & Kaz Kojima
 */

#include <linux/sched.h>
#include <linux/delay.h>

void __delay(unsigned long loops)
{
        __asm__ __volatile__(
                /*
                 * ST40-300 appears to have an issue with this code,
                 * normally taking two cycles each loop, as with all
                 * other SH variants. If however the branch and the
                 * delay slot straddle an 8 byte boundary, this increases
                 * to 3 cycles.
                 * This align directive ensures this doesn't occur.
                 */
                ".balign 8\n\t"

                "tst    %0, %0\n\t"
                "1:\t"
                "bf/s   1b\n\t"
                " dt    %0"
                : "=r" (loops)
                : "0" (loops)
                : "t");
}

inline void __const_udelay(unsigned long xloops)
{
        xloops *= 4;
        __asm__("dmulu.l        %0, %2\n\t"
                "sts    mach, %0"
                : "=r" (xloops)
                : "0" (xloops),
                  "r" (cpu_data[raw_smp_processor_id()].loops_per_jiffy * (HZ/4))
                : "macl", "mach");
        __delay(++xloops);
}

void __udelay(unsigned long usecs)
{
        __const_udelay(usecs * 0x000010c6);  /* 2**32 / 1000000 */
}

void __ndelay(unsigned long nsecs)
{
        __const_udelay(nsecs * 0x00000005);
}