arch/sparc/include/asm/timer_32.h

   1 /*
   2  * timer.h:  Definitions for the timer chips on the Sparc.
   3  *
   4  * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
   5  */
   6
   7
   8 #ifndef _SPARC_TIMER_H
   9 #define _SPARC_TIMER_H
  10
  11 #include <linux/clocksource.h>
  12 #include <linux/irqreturn.h>
  13
  14 #include <asm-generic/percpu.h>
  15
  16 #include <asm/cpu_type.h>  /* For SUN4M_NCPUS */
  17
  18 #define SBUS_CLOCK_RATE   2000000 /* 2MHz */
  19 #define TIMER_VALUE_SHIFT 9
  20 #define TIMER_VALUE_MASK  0x3fffff
  21 #define TIMER_LIMIT_BIT   (1 << 31)  /* Bit 31 in Counter-Timer register */
  22
  23 /* The counter timer register has the value offset by 9 bits.
  24  * From sun4m manual:
  25  * When a counter reaches the value in the corresponding limit register,
  26  * the Limit bit is set and the counter is set to 500 nS (i.e. 0x00000200).
  27  *
  28  * To compensate for this add one to the value.
  29  */
  30 static inline unsigned int timer_value(unsigned int value)
  31 {
  32         return (value + 1) << TIMER_VALUE_SHIFT;
  33 }
  34
  35 extern __volatile__ unsigned int *master_l10_counter;
  36
  37 extern irqreturn_t notrace timer_interrupt(int dummy, void *dev_id);
  38
  39 #ifdef CONFIG_SMP
  40 DECLARE_PER_CPU(struct clock_event_device, sparc32_clockevent);
  41 extern void register_percpu_ce(int cpu);
  42 #endif
  43
  44 #endif /* !(_SPARC_TIMER_H) */