39 строки
904 B
C
39 строки
904 B
C
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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 */
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