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12#ifndef _XTENSA_DELAY_H
13#define _XTENSA_DELAY_H
14
15#include <asm/processor.h>
16#include <asm/param.h>
17
18extern unsigned long loops_per_jiffy;
19
20static inline void __delay(unsigned long loops)
21{
22
23 __asm__ __volatile__ ("1: addi %0, %0, -2; bgeui %0, 2, 1b"
24 : "=r" (loops) : "0" (loops));
25}
26
27static __inline__ u32 xtensa_get_ccount(void)
28{
29 u32 ccount;
30 asm volatile ("rsr %0, 234; # CCOUNT\n" : "=r" (ccount));
31 return ccount;
32}
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37
38static __inline__ void udelay (unsigned long usecs)
39{
40 unsigned long start = xtensa_get_ccount();
41 unsigned long cycles = usecs * (loops_per_jiffy / (1000000UL / HZ));
42
43
44 while (((unsigned long)xtensa_get_ccount()) - start < cycles)
45 ;
46}
47
48#endif
49
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