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7
8#include <linux/module.h>
9#include <linux/sched.h>
10#include <asm/param.h>
11#include <asm/smp.h>
12#include <linux/delay.h>
13
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20
21
22void
23__delay(int loops)
24{
25 int tmp;
26 __asm__ __volatile__(
27 " rpcc %0\n"
28 " addl %1,%0,%1\n"
29 "1: rpcc %0\n"
30 " subl %1,%0,%0\n"
31 " bgt %0,1b"
32 : "=&r" (tmp), "=r" (loops) : "1"(loops));
33}
34EXPORT_SYMBOL(__delay);
35
36#ifdef CONFIG_SMP
37#define LPJ cpu_data[smp_processor_id()].loops_per_jiffy
38#else
39#define LPJ loops_per_jiffy
40#endif
41
42void
43udelay(unsigned long usecs)
44{
45 usecs *= (((unsigned long)HZ << 32) / 1000000) * LPJ;
46 __delay((long)usecs >> 32);
47}
48EXPORT_SYMBOL(udelay);
49
50void
51ndelay(unsigned long nsecs)
52{
53 nsecs *= (((unsigned long)HZ << 32) / 1000000000) * LPJ;
54 __delay((long)nsecs >> 32);
55}
56EXPORT_SYMBOL(ndelay);
57