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/*
* include/asm-v850/delay.h -- Delay routines, using a pre-computed
* "loops_per_second" value
*
* Copyright (C) 2001,03 NEC Corporation
* Copyright (C) 2001,03 Miles Bader <miles@gnu.org>
* Copyright (C) 1994 Hamish Macdonald
*
* This file is subject to the terms and conditions of the GNU General
* Public License. See the file COPYING in the main directory of this
* archive for more details.
*/
#ifndef __V850_DELAY_H__
#define __V850_DELAY_H__
#include <asm/param.h>
static inline void __delay(unsigned long loops)
{
if (loops)
__asm__ __volatile__ ("1: add -1, %0; bnz 1b"
: "=r" (loops) : "0" (loops));
}
/*
* Use only for very small delays ( < 1 msec). Should probably use a
* lookup table, really, as the multiplications take much too long with
* short delays. This is a "reasonable" implementation, though (and the
* first constant multiplications gets optimized away if the delay is
* a constant)
*/
extern unsigned long loops_per_jiffy;
static inline void udelay(unsigned long usecs)
{
register unsigned long full_loops, part_loops;
full_loops = ((usecs * HZ) / 1000000) * loops_per_jiffy;
usecs %= (1000000 / HZ);
part_loops = (usecs * HZ * loops_per_jiffy) / 1000000;
__delay(full_loops + part_loops);
}
#endif /* __V850_DELAY_H__ */
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