mirror of https://gitee.com/openkylin/linux.git
41 lines
1.2 KiB
C
41 lines
1.2 KiB
C
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/*
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* Copyright (C) 2004-2006 Atmel Corporation
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#ifndef __ASM_AVR32_TIMEX_H
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#define __ASM_AVR32_TIMEX_H
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/*
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* This is the frequency of the timer used for Linux's timer interrupt.
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* The value should be defined as accurate as possible or under certain
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* circumstances Linux timekeeping might become inaccurate or fail.
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*
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* For many system the exact clockrate of the timer isn't known but due to
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* the way this value is used we can get away with a wrong value as long
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* as this value is:
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*
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* - a multiple of HZ
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* - a divisor of the actual rate
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*
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* 500000 is a good such cheat value.
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*
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* The obscure number 1193182 is the same as used by the original i8254
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* time in legacy PC hardware; the chip is never found in AVR32 systems.
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*/
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#define CLOCK_TICK_RATE 500000 /* Underlying HZ */
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typedef unsigned long cycles_t;
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static inline cycles_t get_cycles (void)
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{
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return 0;
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}
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extern int read_current_timer(unsigned long *timer_value);
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#define ARCH_HAS_READ_CURRENT_TIMER 1
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#endif /* __ASM_AVR32_TIMEX_H */
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