include/asm-sparc/timer.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 <asm/system.h>  /* For SUN4M_NCPUS */
  12 #include <asm/sun4paddr.h>
  13 #include <asm/btfixup.h>
  14
  15 /* Timer structures. The interrupt timer has two properties which
  16  * are the counter (which is handled in do_timer in sched.c) and the limit.
  17  * This limit is where the timer's counter 'wraps' around. Oddly enough,
  18  * the sun4c timer when it hits the limit wraps back to 1 and not zero
  19  * thus when calculating the value at which it will fire a microsecond you
  20  * must adjust by one.  Thanks SUN for designing such great hardware ;(
  21  */
  22
  23 /* Note that I am only going to use the timer that interrupts at
  24  * Sparc IRQ 10.  There is another one available that can fire at
  25  * IRQ 14. Currently it is left untouched, we keep the PROM's limit
  26  * register value and let the prom take these interrupts.  This allows
  27  * L1-A to work.
  28  */
  29
  30 struct sun4c_timer_info {
  31   __volatile__ unsigned int cur_count10;
  32   __volatile__ unsigned int timer_limit10;
  33   __volatile__ unsigned int cur_count14;
  34   __volatile__ unsigned int timer_limit14;
  35 };
  36
  37 #define SUN4C_TIMER_PHYSADDR   0xf3000000
  38 #ifdef CONFIG_SUN4
  39 #define SUN_TIMER_PHYSADDR SUN4_300_TIMER_PHYSADDR
  40 #else
  41 #define SUN_TIMER_PHYSADDR SUN4C_TIMER_PHYSADDR
  42 #endif
  43
  44 /* A sun4m has two blocks of registers which are probably of the same
  45  * structure. LSI Logic's L64851 is told to _decrement_ from the limit
  46  * value. Aurora behaves similarly but its limit value is compacted in
  47  * other fashion (it's wider). Documented fields are defined here.
  48  */
  49
  50 /* As with the interrupt register, we have two classes of timer registers
  51  * which are per-cpu and master.  Per-cpu timers only hit that cpu and are
  52  * only level 14 ticks, master timer hits all cpus and is level 10.
  53  */
  54
  55 #define SUN4M_PRM_CNT_L       0x80000000
  56 #define SUN4M_PRM_CNT_LVALUE  0x7FFFFC00
  57
  58 struct sun4m_timer_percpu_info {
  59   __volatile__ unsigned int l14_timer_limit;    /* Initial value is 0x009c4000 */
  60   __volatile__ unsigned int l14_cur_count;
  61
  62   /* This register appears to be write only and/or inaccessible
  63    * on Uni-Processor sun4m machines.
  64    */
  65   __volatile__ unsigned int l14_limit_noclear;  /* Data access error is here */
  66
  67   __volatile__ unsigned int cntrl;            /* =1 after POST on Aurora */
  68   __volatile__ unsigned char space[PAGE_SIZE - 16];
  69 };
  70
  71 struct sun4m_timer_regs {
  72         struct sun4m_timer_percpu_info cpu_timers[SUN4M_NCPUS];
  73         volatile unsigned int l10_timer_limit;
  74         volatile unsigned int l10_cur_count;
  75
  76         /* Again, this appears to be write only and/or inaccessible
  77          * on uni-processor sun4m machines.
  78          */
  79         volatile unsigned int l10_limit_noclear;
  80
  81         /* This register too, it must be magic. */
  82         volatile unsigned int foobar;
  83
  84         volatile unsigned int cfg;     /* equals zero at boot time... */
  85 };
  86
  87 extern struct sun4m_timer_regs *sun4m_timers;
  88
  89 #define SUN4D_PRM_CNT_L       0x80000000
  90 #define SUN4D_PRM_CNT_LVALUE  0x7FFFFC00
  91
  92 struct sun4d_timer_regs {
  93         volatile unsigned int l10_timer_limit;
  94         volatile unsigned int l10_cur_countx;
  95         volatile unsigned int l10_limit_noclear;
  96         volatile unsigned int ctrl;
  97         volatile unsigned int l10_cur_count;
  98 };
  99
 100 extern struct sun4d_timer_regs *sun4d_timers;
 101
 102 extern __volatile__ unsigned int *master_l10_counter;
 103 extern __volatile__ unsigned int *master_l10_limit;
 104
 105 /* FIXME: Make do_[gs]ettimeofday btfixup calls */
 106 BTFIXUPDEF_CALL(int, bus_do_settimeofday, struct timespec *tv)
 107 #define bus_do_settimeofday(tv) BTFIXUP_CALL(bus_do_settimeofday)(tv)
 108
 109 #endif /* !(_SPARC_TIMER_H) */