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timex.h
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1 /*
2  * linux/include/asm-alpha/timex.h
3  *
4  * ALPHA architecture timex specifications
5  */
6 #ifndef _ASMALPHA_TIMEX_H
7 #define _ASMALPHA_TIMEX_H
8 
9 /* With only one or two oddballs, we use the RTC as the ticker, selecting
10  the 32.768kHz reference clock, which nicely divides down to our HZ. */
11 #define CLOCK_TICK_RATE 32768
12 
13 /*
14  * Standard way to access the cycle counter.
15  * Currently only used on SMP for scheduling.
16  *
17  * Only the low 32 bits are available as a continuously counting entity.
18  * But this only means we'll force a reschedule every 8 seconds or so,
19  * which isn't an evil thing.
20  */
21 
22 typedef unsigned int cycles_t;
23 
24 static inline cycles_t get_cycles (void)
25 {
26  cycles_t ret;
27  __asm__ __volatile__ ("rpcc %0" : "=r"(ret));
28  return ret;
29 }
30 
31 #endif