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| Rev | Author | Line No. | Line |
|---|---|---|---|
| 168 | giacomo | 1 | #ifndef _LINUX_DELAY_H |
| 2 | #define _LINUX_DELAY_H |
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| 3 | |||
| 4 | /* |
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| 5 | * Copyright (C) 1993 Linus Torvalds |
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| 6 | * |
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| 7 | * Delay routines, using a pre-computed "loops_per_jiffy" value. |
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| 8 | */ |
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| 9 | |||
| 10 | extern unsigned long loops_per_jiffy; |
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| 11 | |||
| 218 | giacomo | 12 | /*#include <asm/delay.h>*/ |
| 168 | giacomo | 13 | |
| 14 | /* |
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| 15 | * Using udelay() for intervals greater than a few milliseconds can |
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| 16 | * risk overflow for high loops_per_jiffy (high bogomips) machines. The |
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| 17 | * mdelay() provides a wrapper to prevent this. For delays greater |
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| 18 | * than MAX_UDELAY_MS milliseconds, the wrapper is used. Architecture |
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| 19 | * specific values can be defined in asm-???/delay.h as an override. |
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| 20 | * The 2nd mdelay() definition ensures GCC will optimize away the |
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| 21 | * while loop for the common cases where n <= MAX_UDELAY_MS -- Paul G. |
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| 22 | */ |
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| 23 | |||
| 24 | #ifndef MAX_UDELAY_MS |
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| 25 | #define MAX_UDELAY_MS 5 |
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| 26 | #endif |
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| 27 | |||
| 28 | #ifdef notdef |
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| 29 | #define mdelay(n) (\ |
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| 30 | {unsigned long msec=(n); while (msec--) udelay(1000);}) |
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| 31 | #else |
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| 32 | #define mdelay(n) (\ |
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| 33 | (__builtin_constant_p(n) && (n)<=MAX_UDELAY_MS) ? udelay((n)*1000) : \ |
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| 34 | ({unsigned long msec=(n); while (msec--) udelay(1000);})) |
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| 35 | #endif |
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| 36 | |||
| 37 | #endif /* defined(_LINUX_DELAY_H) */ |