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linux/arch/mips/include/asm/i8253.h
Arnd Bergmann 08604bd993 time: move PIT_TICK_RATE to linux/timex.h
PIT_TICK_RATE is currently defined in four architectures, but in three
different places.  While linux/timex.h is not the perfect place for it, it
is still a reasonable replacement for those drivers that traditionally use
asm/timex.h to get CLOCK_TICK_RATE and expect it to be the PIT frequency.

Note that for Alpha, the actual value changed from 1193182UL to 1193180UL.
 This is unlikely to make a difference, and probably can only improve
accuracy.  There was a discussion on the correct value of CLOCK_TICK_RATE
a few years ago, after which every existing instance was getting changed
to 1193182.  According to the specification, it should be
1193181.818181...

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Len Brown <lenb@kernel.org>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Dmitry Torokhov <dtor@mail.ru>
Cc: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-16 19:47:27 -07:00

20 lines
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C

/*
* Machine specific IO port address definition for generic.
* Written by Osamu Tomita <tomita@cinet.co.jp>
*/
#ifndef __ASM_I8253_H
#define __ASM_I8253_H
#include <linux/spinlock.h>
/* i8253A PIT registers */
#define PIT_MODE 0x43
#define PIT_CH0 0x40
#define PIT_CH2 0x42
extern spinlock_t i8253_lock;
extern void setup_pit_timer(void);
#endif /* __ASM_I8253_H */