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Diffstat (limited to 'include/asm-ia64/timex.h')
-rw-r--r-- | include/asm-ia64/timex.h | 40 |
1 files changed, 40 insertions, 0 deletions
diff --git a/include/asm-ia64/timex.h b/include/asm-ia64/timex.h new file mode 100644 index 00000000000..414aae06044 --- /dev/null +++ b/include/asm-ia64/timex.h @@ -0,0 +1,40 @@ +#ifndef _ASM_IA64_TIMEX_H +#define _ASM_IA64_TIMEX_H + +/* + * Copyright (C) 1998-2001, 2003 Hewlett-Packard Co + * David Mosberger-Tang <davidm@hpl.hp.com> + */ +/* + * 2001/01/18 davidm Removed CLOCK_TICK_RATE. It makes no sense on IA-64. + * Also removed cacheflush_time as it's entirely unused. + */ + +#include <asm/intrinsics.h> +#include <asm/processor.h> + +typedef unsigned long cycles_t; + +/* + * For performance reasons, we don't want to define CLOCK_TICK_TRATE as + * local_cpu_data->itc_rate. Fortunately, we don't have to, either: according to George + * Anzinger, 1/CLOCK_TICK_RATE is taken as the resolution of the timer clock. The time + * calculation assumes that you will use enough of these so that your tick size <= 1/HZ. + * If the calculation shows that your CLOCK_TICK_RATE can not supply exactly 1/HZ ticks, + * the actual value is calculated and used to update the wall clock each jiffie. Setting + * the CLOCK_TICK_RATE to x*HZ insures that the calculation will find no errors. Hence we + * pick a multiple of HZ which gives us a (totally virtual) CLOCK_TICK_RATE of about + * 100MHz. + */ +#define CLOCK_TICK_RATE (HZ * 100000UL) + +static inline cycles_t +get_cycles (void) +{ + cycles_t ret; + + ret = ia64_getreg(_IA64_REG_AR_ITC); + return ret; +} + +#endif /* _ASM_IA64_TIMEX_H */ |