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- /*
- * linux/include/asm-i386/timex.h
- *
- * i386 architecture timex specifications
- */
- #ifndef _ASMi386_TIMEX_H
- #define _ASMi386_TIMEX_H
-
- #include <linux/config.h>
- #include <asm/processor.h>
-
- #ifdef CONFIG_X86_ELAN
- # define CLOCK_TICK_RATE 1189200 /* AMD Elan has different frequency! */
- #else
- # define CLOCK_TICK_RATE 1193182 /* Underlying HZ */
- #endif
-
-
- /*
- * Standard way to access the cycle counter on i586+ CPUs.
- * Currently only used on SMP.
- *
- * If you really have a SMP machine with i486 chips or older,
- * compile for that, and this will just always return zero.
- * That's ok, it just means that the nicer scheduling heuristics
- * won't work for you.
- *
- * We only use the low 32 bits, and we'd simply better make sure
- * that we reschedule before that wraps. Scheduling at least every
- * four billion cycles just basically sounds like a good idea,
- * regardless of how fast the machine is.
- */
- typedef unsigned long long cycles_t;
-
- extern cycles_t cacheflush_time;
-
- static inline cycles_t get_cycles (void)
- {
- unsigned long long ret=0;
-
- #ifndef CONFIG_X86_TSC
- if (!cpu_has_tsc)
- return 0;
- #endif
-
- #if defined(CONFIG_X86_GENERIC) || defined(CONFIG_X86_TSC)
- rdtscll(ret);
- #endif
- return ret;
- }
-
- extern unsigned long cpu_khz;
-
- #endif
-