i386/linux-2.3.21/arch/sparc/ap1000/timer.c

   1   /*
   2    * Copyright 1996 The Australian National University.
   3    * Copyright 1996 Fujitsu Laboratories Limited
   4    *
   5    * This software may be distributed under the terms of the Gnu
   6    * Public License version 2 or later
   7   */
   8 /* routines to control the AP1000 timer chip */
   9
  10 #include <linux/time.h>
  11 #include <linux/sched.h>
  12 #include <linux/interrupt.h>
  13 #include <linux/mm.h>
  14 #include <linux/malloc.h>
  15 #include <asm/ap1000/apservice.h>
  16 #include <asm/ap1000/apreg.h>
  17 #include <asm/irq.h>
  18
  19 #define INIT_TIM1       (781250/HZ)
  20 #define INIT_TIM0       (781250/(10*HZ))
  21
  22 static unsigned long last_freerun;
  23
  24 unsigned ap_freerun(void)
  25 {
  26         return *((volatile unsigned long *)(MC_FREERUN + 4));
  27 }
  28
  29 void ap_clear_clock_irq(void)
  30 {
  31         MC_OUT(MC_INTR, AP_CLR_INTR_REQ << MC_INTR_ITIM1_SH);
  32         last_freerun = *((unsigned long *)(MC_FREERUN + 4));
  33         tnet_check_completion();
  34 #if 1
  35         if ((((unsigned)jiffies) % (HZ/4)) == 0) {
  36                 msc_timer();
  37                 ap_xor_led(1);
  38                 bif_timer();
  39                 ap_dbg_flush();
  40 #if 0
  41                 bif_led_status();
  42 #endif
  43         }
  44 #endif
  45 }
  46
  47
  48 void ap_gettimeofday(struct timeval *xt)
  49 {
  50         unsigned long d;
  51         unsigned v;
  52         unsigned long new_freerun;
  53
  54         /* this is in 80ns units - we only use the low 32 bits
  55            as 5mins is plenty for this stuff */
  56         d = new_freerun = *((unsigned long *)(MC_FREERUN + 4));
  57
  58         if (d < last_freerun) {
  59                 /* wraparound */
  60                 d += ((~0) - last_freerun);
  61         } else {
  62                 d -= last_freerun;
  63         }
  64
  65         /* convert to microseconds */
  66         v = ((d&0xffffff)*10)/125;
  67
  68         /* only want microseconds/HZ */
  69         v = v%(1000000/HZ);
  70
  71         xt->tv_usec += v;
  72
  73         last_freerun = new_freerun;
  74 }
  75
  76 static void profile_interrupt(int irq, void *dev_id, struct pt_regs * regs)
  77 {
  78   if (prof_buffer && current->pid) {
  79     extern int _stext;
  80     unsigned long ip = instruction_pointer(regs);
  81     ip -= (unsigned long) &_stext;
  82     ip >>= prof_shift;
  83     if (ip < prof_len)
  84       prof_buffer[ip]++;
  85   }
  86   MC_OUT(MC_INTR,AP_CLR_INTR_REQ << MC_INTR_ITIM0_SH);
  87 }
  88
  89 void ap_profile_init(void)
  90 {
  91   if (prof_shift) {
  92     printk("Initialising profiling with prof_shift=%d\n",(int)prof_shift);
  93     MC_OUT(MC_INTR,AP_CLR_INTR_REQ << MC_INTR_ITIM0_SH);
  94     MC_OUT(MC_INTR,AP_CLR_INTR_MASK << MC_INTR_ITIM0_SH);
  95   }
  96 }
  97
  98 void ap_init_timers(void)
  99 {
 100         extern void timer_interrupt(int irq, void *dev_id, struct pt_regs * regs);
 101         unsigned flags;
 102
 103         printk("Initialising ap1000 timer\n");
 104
 105         save_flags(flags); cli();
 106
 107         request_irq(APTIM1_IRQ,
 108                     timer_interrupt,
 109                     (SA_INTERRUPT | SA_STATIC_ALLOC),
 110                     "timer", NULL);
 111
 112         request_irq(APTIM0_IRQ,
 113                     profile_interrupt,
 114                     (SA_INTERRUPT | SA_STATIC_ALLOC),
 115                     "profile", NULL);
 116
 117         ap_clear_clock_irq();
 118
 119         MC_OUT(MC_ITIMER0,INIT_TIM0);
 120         MC_OUT(MC_ITIMER1,INIT_TIM1);
 121         MC_OUT(MC_INTR,AP_CLR_INTR_REQ << MC_INTR_ITIM1_SH);
 122         MC_OUT(MC_INTR,AP_CLR_INTR_MASK << MC_INTR_ITIM1_SH);
 123         MC_OUT(MC_INTR,AP_SET_INTR_MASK << MC_INTR_ITIM0_SH);
 124         restore_flags(flags);
 125 }