i386/linux-2.3.21/include/asm-mips/timex.h

   1 /* $Id: timex.h,v 1.2 1999/02/15 02:22:14 ralf Exp $
   2  *
   3  * This file is subject to the terms and conditions of the GNU General Public
   4  * License.  See the file "COPYING" in the main directory of this archive
   5  * for more details.
   6  *
   7  * Copyright (C) 1998, 1999 by Ralf Baechle
   8  *
   9  * FIXME: For some of the supported machines this is dead wrong.
  10  */
  11 #ifndef __ASM_MIPS_TIMEX_H
  12 #define __ASM_MIPS_TIMEX_H
  13
  14 #define CLOCK_TICK_RATE 1193180 /* Underlying HZ */
  15 #define CLOCK_TICK_FACTOR       20      /* Factor of both 1000000 and CLOCK_TICK_RATE */
  16 #define FINETUNE ((((((long)LATCH * HZ - CLOCK_TICK_RATE) << SHIFT_HZ) * \
  17         (1000000/CLOCK_TICK_FACTOR) / (CLOCK_TICK_RATE/CLOCK_TICK_FACTOR)) \
  18                 << (SHIFT_SCALE-SHIFT_HZ)) / HZ)
  19
  20 /*
  21  * Standard way to access the cycle counter.
  22  * Currently only used on SMP for scheduling.
  23  *
  24  * Only the low 32 bits are available as a continuously counting entity.
  25  * But this only means we'll force a reschedule every 8 seconds or so,
  26  * which isn't an evil thing.
  27  *
  28  * We know that all SMP capable CPUs have cycle counters.
  29  */
  30
  31 typedef unsigned int cycles_t;
  32 extern cycles_t cacheflush_time;
  33
  34 static inline cycles_t get_cycles (void)
  35 {
  36         return read_32bit_cp0_register(CP0_COUNT);
  37 }
  38
  39 #endif /*  __ASM_MIPS_TIMEX_H */