61 lines
1.4 KiB
C
61 lines
1.4 KiB
C
/*
|
|
* 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);
|