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delay.h
Package: linux-2.4.20.tar.gz　[view]
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Upload Date: 2013-04-10
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Linux-Unix program

Development Platform:

Unix_Linux

delay.h：Code Content
  1. #ifndef _CRIS_DELAY_H
  2. #define _CRIS_DELAY_H
  4. /*
  5.  * Copyright (C) 1998, 1999, 2000, 2001 Axis Communications AB
  6.  *
  7.  * Delay routines, using a pre-computed "loops_per_second" value.
  8.  */
  10. #include <linux/config.h>
  11. #include <linux/linkage.h>
  13. #ifdef CONFIG_SMP
  14. #include <asm/smp.h>
  15. #endif 
  17. extern void __do_delay(void); /* Special register call calling convention */
  19. extern __inline__ void __delay(int loops)
  20. {
  21. __asm__ __volatile__ (
  22.       "move.d %0,$r9nt"
  23.       "beq 2fnt"
  24.       "subq 1,$r9nt"
  25.       "1:nt"
  26.       "bne 1bnt"
  27.       "subq 1,$r9n"
  28.       "2:"
  29.       : : "g" (loops) : "r9");
  30. }
  33. /* Use only for very small delays ( < 1 msec).  */
  35. extern unsigned long loops_per_usec; /* arch/cris/mm/init.c */
  37. extern __inline__ void udelay(unsigned long usecs)
  38. {
  39. __delay(usecs * loops_per_usec);
  40. }
  42. #endif /* defined(_CRIS_DELAY_H) */