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-rw-r--r--include/asm-i386/timex.h34
1 files changed, 1 insertions, 33 deletions
diff --git a/include/asm-i386/timex.h b/include/asm-i386/timex.h
index d434984303ca..3666044409f0 100644
--- a/include/asm-i386/timex.h
+++ b/include/asm-i386/timex.h
@@ -7,6 +7,7 @@
7#define _ASMi386_TIMEX_H 7#define _ASMi386_TIMEX_H
8 8
9#include <asm/processor.h> 9#include <asm/processor.h>
10#include <asm/tsc.h>
10 11
11#ifdef CONFIG_X86_ELAN 12#ifdef CONFIG_X86_ELAN
12# define CLOCK_TICK_RATE 1189200 /* AMD Elan has different frequency! */ 13# define CLOCK_TICK_RATE 1189200 /* AMD Elan has different frequency! */
@@ -15,39 +16,6 @@
15#endif 16#endif
16 17
17 18
18/*
19 * Standard way to access the cycle counter on i586+ CPUs.
20 * Currently only used on SMP.
21 *
22 * If you really have a SMP machine with i486 chips or older,
23 * compile for that, and this will just always return zero.
24 * That's ok, it just means that the nicer scheduling heuristics
25 * won't work for you.
26 *
27 * We only use the low 32 bits, and we'd simply better make sure
28 * that we reschedule before that wraps. Scheduling at least every
29 * four billion cycles just basically sounds like a good idea,
30 * regardless of how fast the machine is.
31 */
32typedef unsigned long long cycles_t;
33
34static inline cycles_t get_cycles (void)
35{
36 unsigned long long ret=0;
37
38#ifndef CONFIG_X86_TSC
39 if (!cpu_has_tsc)
40 return 0;
41#endif
42
43#if defined(CONFIG_X86_GENERIC) || defined(CONFIG_X86_TSC)
44 rdtscll(ret);
45#endif
46 return ret;
47}
48
49extern unsigned int cpu_khz;
50
51extern int read_current_timer(unsigned long *timer_value); 19extern int read_current_timer(unsigned long *timer_value);
52#define ARCH_HAS_READ_CURRENT_TIMER 1 20#define ARCH_HAS_READ_CURRENT_TIMER 1
53 21