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- /*
- * Copyright (C) 1995-2004 Russell King
- *
- * Delay routines, using a pre-computed "loops_per_second" value.
- */
- #ifndef __ASM_ARM_DELAY_H
- #define __ASM_ARM_DELAY_H
- #include <asm/param.h> /* HZ */
- extern void __delay(int loops);
- /*
- * This function intentionally does not exist; if you see references to
- * it, it means that you're calling udelay() with an out of range value.
- *
- * With currently imposed limits, this means that we support a max delay
- * of 2000us. Further limits: HZ<=1000 and bogomips<=3355
- */
- extern void __bad_udelay(void);
- /*
- * division by multiplication: you don't have to worry about
- * loss of precision.
- *
- * 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 void __udelay(unsigned long usecs);
- extern void __const_udelay(unsigned long);
- #define MAX_UDELAY_MS 2
- #define udelay(n) \
- (__builtin_constant_p(n) ? \
- ((n) > (MAX_UDELAY_MS * 1000) ? __bad_udelay() : \
- __const_udelay((n) * ((2199023U*HZ)>>11))) : \
- __udelay(n))
- #endif /* defined(_ARM_DELAY_H) */
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