1 #ifndef _ASM_IA64_TIMEX_H
2 #define _ASM_IA64_TIMEX_H
3
4 /*
5 * Copyright (C) 1998-2001, 2003 Hewlett-Packard Co
6 * David Mosberger-Tang <davidm@hpl.hp.com>
7 */
8 /*
9 * 2001/01/18 davidm Removed CLOCK_TICK_RATE. It makes no sense on IA-64.
10 * Also removed cacheflush_time as it's entirely unused.
11 */
12
13 #include <asm/intrinsics.h>
14 #include <asm/processor.h>
15
16 typedef unsigned long cycles_t;
17
18 extern void (*ia64_udelay)(unsigned long usecs);
19
20 /*
21 * For performance reasons, we don't want to define CLOCK_TICK_TRATE as
22 * local_cpu_data->itc_rate. Fortunately, we don't have to, either: according to George
23 * Anzinger, 1/CLOCK_TICK_RATE is taken as the resolution of the timer clock. The time
24 * calculation assumes that you will use enough of these so that your tick size <= 1/HZ.
25 * If the calculation shows that your CLOCK_TICK_RATE can not supply exactly 1/HZ ticks,
26 * the actual value is calculated and used to update the wall clock each jiffie. Setting
27 * the CLOCK_TICK_RATE to x*HZ insures that the calculation will find no errors. Hence we
28 * pick a multiple of HZ which gives us a (totally virtual) CLOCK_TICK_RATE of about
29 * 100MHz.
30 */
31 #define CLOCK_TICK_RATE (HZ * 100000UL)
32
33 static inline cycles_t
get_cycles(void)34 get_cycles (void)
35 {
36 cycles_t ret;
37
38 ret = ia64_getreg(_IA64_REG_AR_ITC);
39 return ret;
40 }
41
42 extern void ia64_cpu_local_tick (void);
43 extern unsigned long long ia64_native_sched_clock (void);
44
45 #endif /* _ASM_IA64_TIMEX_H */
46