mirror of https://gitee.com/openkylin/linux.git
35 lines
820 B
C
35 lines
820 B
C
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#ifndef __ASM_ARM_DELAY_H
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#define __ASM_ARM_DELAY_H
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/*
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* Copyright (C) 1995 Russell King
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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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extern void __delay(int loops);
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/*
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* division by multiplication: you don't have to worry about
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* loss of precision.
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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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* FIXME - lets improve it then...
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*/
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extern void udelay(unsigned long usecs);
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static inline unsigned long muldiv(unsigned long a, unsigned long b, unsigned long c)
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{
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return a * b / c;
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}
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#endif /* defined(_ARM_DELAY_H) */
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