arch/mn10300/kernel/profile.c

   1 /* MN10300 Profiling setup
   2  *
   3  * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
   4  * Written by David Howells (dhowells@redhat.com)
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public Licence
   8  * as published by the Free Software Foundation; either version
   9  * 2 of the Licence, or (at your option) any later version.
  10  */
  11
  12 /*
  13  * initialise the profiling if enabled
  14  * - using with gdbstub will give anomalous results
  15  * - can't be used with gdbstub if running at IRQ priority 0
  16  */
  17 static __init int profile_init(void)
  18 {
  19         u16 tmp;
  20
  21         if (!prof_buffer)
  22                 return 0;
  23
  24         /* use timer 11 to drive the profiling interrupts */
  25         set_intr_stub(EXCEP_IRQ_LEVEL0, profile_handler);
  26
  27         /* set IRQ priority at which to run */
  28         set_intr_level(TM11IRQ, GxICR_LEVEL_0);
  29
  30         /* set up timer 11
  31          * - source: (IOCLK 33MHz)*2 = 66MHz
  32          * - frequency: (33330000*2) / 8 / 20625 = 202Hz
  33          */
  34         TM11BR = 20625 - 1;
  35         TM11MD = TM8MD_SRC_IOCLK_8;
  36         TM11MD |= TM8MD_INIT_COUNTER;
  37         TM11MD &= ~TM8MD_INIT_COUNTER;
  38         TM11MD |= TM8MD_COUNT_ENABLE;
  39
  40         TM11ICR |= GxICR_ENABLE;
  41         tmp = TM11ICR;
  42
  43         printk(KERN_INFO "Profiling initiated on timer 11, priority 0, %uHz\n",
  44                mn10300_ioclk / 8 / (TM11BR + 1));
  45         printk(KERN_INFO "Profile histogram stored %p-%p\n",
  46                prof_buffer, (u8 *)(prof_buffer + prof_len) - 1);
  47
  48         return 0;
  49 }
  50
  51 __initcall(profile_init);