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/*
* OpenRISC Linux
*
* Linux architectural port borrowing liberally from similar works of
* others. All original copyrights apply as per the original source
* declaration.
*
* Modifications for the OpenRISC architecture:
* Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* version 2 as published by the Free Software Foundation
*
* Precise Delay Loops
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <asm/delay.h>
#include <asm/timex.h>
#include <asm/processor.h>
int __devinit read_current_timer(unsigned long *timer_value)
{
*timer_value = mfspr(SPR_TTCR);
return 0;
}
void __delay(unsigned long cycles)
{
cycles_t target = get_cycles() + cycles;
while (get_cycles() < target)
cpu_relax();
}
EXPORT_SYMBOL(__delay);
inline void __const_udelay(unsigned long xloops)
{
unsigned long long loops;
loops = xloops * loops_per_jiffy * HZ;
__delay(loops >> 32);
}
EXPORT_SYMBOL(__const_udelay);
void __udelay(unsigned long usecs)
{
__const_udelay(usecs * 0x10C7UL); /* 2**32 / 1000000 (rounded up) */
}
EXPORT_SYMBOL(__udelay);
void __ndelay(unsigned long nsecs)
{
__const_udelay(nsecs * 0x5UL); /* 2**32 / 1000000000 (rounded up) */
}
EXPORT_SYMBOL(__ndelay);
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