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Viewing changes to arch/h8300/include/asm/delay.h

  • Committer: Package Import Robot
  • Author(s): Alessio Igor Bogani
  • Date: 2011-10-26 11:13:05 UTC
  • Revision ID: package-import@ubuntu.com-20111026111305-tz023xykf0i6eosh
Tags: upstream-3.2.0
Import upstream version 3.2.0

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arch/h8300/include/asm/delay.h
 
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#ifndef _H8300_DELAY_H
 
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#define _H8300_DELAY_H
 
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#include <asm/param.h>
 
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/*
 
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 * Copyright (C) 2002 Yoshinori Sato <ysato@sourceforge.jp>
 
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 *
 
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 * Delay routines, using a pre-computed "loops_per_second" value.
 
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 */
 
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static inline void __delay(unsigned long loops)
 
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{
 
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        __asm__ __volatile__ ("1:\n\t"
 
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                              "dec.l #1,%0\n\t"
 
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                              "bne 1b"
 
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                              :"=r" (loops):"0"(loops));
 
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}
 
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/*
 
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 * Use only for very small delays ( < 1 msec).  Should probably use a
 
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 * lookup table, really, as the multiplications take much too long with
 
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 * short delays.  This is a "reasonable" implementation, though (and the
 
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 * first constant multiplications gets optimized away if the delay is
 
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 * a constant)  
 
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 */
 
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extern unsigned long loops_per_jiffy;
 
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static inline void udelay(unsigned long usecs)
 
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{
 
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        usecs *= 4295;          /* 2**32 / 1000000 */
 
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        usecs /= (loops_per_jiffy*HZ);
 
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        if (usecs)
 
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                __delay(usecs);
 
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}
 
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#endif /* _H8300_DELAY_H */