Blame view

kernel/linux-rt-4.4.41/arch/h8300/lib/delay.c 762 Bytes
5113f6f70   김현기   kernel add
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
  /*
   * delay loops
   *
   * Copyright (C) 2015 Yoshinori Sato
   */
  
  #include <linux/module.h>
  #include <linux/delay.h>
  #include <asm/param.h>
  #include <asm/processor.h>
  #include <asm/timex.h>
  
  void __delay(unsigned long cycles)
  {
  	__asm__ volatile ("1: dec.l #1,%0
  \t"
  			  "bne 1b":"=r"(cycles):"0"(cycles));
  }
  EXPORT_SYMBOL(__delay);
  
  void __const_udelay(unsigned long xloops)
  {
  	u64 loops;
  
  	loops = (u64)xloops * loops_per_jiffy * HZ;
  
  	__delay(loops >> 32);
  }
  EXPORT_SYMBOL(__const_udelay);
  
  void __udelay(unsigned long usecs)
  {
  	__const_udelay(usecs * 0x10C7UL); /* 2**32 / 1000000 (rounded up) */
  }
  EXPORT_SYMBOL(__udelay);
  
  void __ndelay(unsigned long nsecs)
  {
  	__const_udelay(nsecs * 0x5UL); /* 2**32 / 1000000000 (rounded up) */
  }
  EXPORT_SYMBOL(__ndelay);