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kernel/linux-rt-4.4.41/arch/avr32/include/asm/timex.h 1.13 KB
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  /*
   * Copyright (C) 2004-2006 Atmel Corporation
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License version 2 as
   * published by the Free Software Foundation.
   */
  #ifndef __ASM_AVR32_TIMEX_H
  #define __ASM_AVR32_TIMEX_H
  
  /*
   * This is the frequency of the timer used for Linux's timer interrupt.
   * The value should be defined as accurate as possible or under certain
   * circumstances Linux timekeeping might become inaccurate or fail.
   *
   * For many system the exact clockrate of the timer isn't known but due to
   * the way this value is used we can get away with a wrong value as long
   * as this value is:
   *
   *  - a multiple of HZ
   *  - a divisor of the actual rate
   *
   * 500000 is a good such cheat value.
   *
   * The obscure number 1193182 is the same as used by the original i8254
   * time in legacy PC hardware; the chip is never found in AVR32 systems.
   */
  #define CLOCK_TICK_RATE		500000	/* Underlying HZ */
  
  typedef unsigned long cycles_t;
  
  static inline cycles_t get_cycles (void)
  {
  	return 0;
  }
  
  #define ARCH_HAS_READ_CURRENT_TIMER
  
  #endif /* __ASM_AVR32_TIMEX_H */