arch/sparc/kernel/tick14.c

   1 /* tick14.c
   2  * linux/arch/sparc/kernel/tick14.c
   3  *
   4  * Copyright (C) 1996 David Redman (djhr@tadpole.co.uk)
   5  *
   6  * This file handles the Sparc specific level14 ticker
   7  * This is really useful for profiling OBP uses it for keyboard
   8  * aborts and other stuff.
   9  *
  10  *
  11  */
  12 #include <linux/errno.h>
  13 #include <linux/sched.h>
  14 #include <linux/kernel.h>
  15 #include <linux/param.h>
  16 #include <linux/string.h>
  17 #include <linux/mm.h>
  18 #include <linux/timex.h>
  19 #include <linux/interrupt.h>
  20
  21 #include <asm/oplib.h>
  22 #include <asm/timer.h>
  23 #include <asm/mostek.h>
  24 #include <asm/system.h>
  25 #include <asm/irq.h>
  26 #include <asm/io.h>
  27
  28 #include "irq.h"
  29
  30 extern unsigned long lvl14_save[5];
  31 static unsigned long *linux_lvl14 = NULL;
  32 static unsigned long obp_lvl14[4];
  33
  34 /*
  35  * Call with timer IRQ closed.
  36  * First time we do it with disable_irq, later prom code uses spin_lock_irq().
  37  */
  38 void install_linux_ticker(void)
  39 {
  40
  41         if (!linux_lvl14)
  42                 return;
  43         linux_lvl14[0] =  lvl14_save[0];
  44         linux_lvl14[1] =  lvl14_save[1];
  45         linux_lvl14[2] =  lvl14_save[2];
  46         linux_lvl14[3] =  lvl14_save[3];
  47 }
  48
  49 void install_obp_ticker(void)
  50 {
  51
  52         if (!linux_lvl14)
  53                 return;
  54         linux_lvl14[0] =  obp_lvl14[0];
  55         linux_lvl14[1] =  obp_lvl14[1];
  56         linux_lvl14[2] =  obp_lvl14[2];
  57         linux_lvl14[3] =  obp_lvl14[3];
  58 }
  59
  60 void claim_ticker14(irq_handler_t handler,
  61                     int irq_nr, unsigned int timeout )
  62 {
  63         int cpu = smp_processor_id();
  64
  65         /* first we copy the obp handler instructions
  66          */
  67         __disable_irq(irq_nr);
  68         if (!handler)
  69                 return;
  70
  71         linux_lvl14 = (unsigned long *)lvl14_save[4];
  72         obp_lvl14[0] = linux_lvl14[0];
  73         obp_lvl14[1] = linux_lvl14[1];
  74         obp_lvl14[2] = linux_lvl14[2];
  75         obp_lvl14[3] = linux_lvl14[3];
  76
  77         if (!request_irq(irq_nr,
  78                          handler,
  79                          (IRQF_DISABLED | SA_STATIC_ALLOC),
  80                          "counter14",
  81                          NULL)) {
  82                 install_linux_ticker();
  83                 load_profile_irq(cpu, timeout);
  84                 __enable_irq(irq_nr);
  85         }
  86 }