arch/sh/kernel/localtimer.c

   1 /*
   2  * Dummy local timer
   3  *
   4  * Copyright (C) 2008  Paul Mundt
   5  *
   6  * cloned from:
   7  *
   8  *  linux/arch/arm/mach-realview/localtimer.c
   9  *
  10  *  Copyright (C) 2002 ARM Ltd.
  11  *  All Rights Reserved
  12  *
  13  * This program is free software; you can redistribute it and/or modify
  14  * it under the terms of the GNU General Public License version 2 as
  15  * published by the Free Software Foundation.
  16  */
  17 #include <linux/init.h>
  18 #include <linux/kernel.h>
  19 #include <linux/delay.h>
  20 #include <linux/device.h>
  21 #include <linux/smp.h>
  22 #include <linux/jiffies.h>
  23 #include <linux/percpu.h>
  24 #include <linux/clockchips.h>
  25 #include <linux/hardirq.h>
  26 #include <linux/irq.h>
  27
  28 static DEFINE_PER_CPU(struct clock_event_device, local_clockevent);
  29
  30 /*
  31  * Used on SMP for either the local timer or SMP_MSG_TIMER
  32  */
  33 void local_timer_interrupt(void)
  34 {
  35         struct clock_event_device *clk = &__get_cpu_var(local_clockevent);
  36
  37         irq_enter();
  38         clk->event_handler(clk);
  39         irq_exit();
  40 }
  41
  42 static void dummy_timer_set_mode(enum clock_event_mode mode,
  43                                  struct clock_event_device *clk)
  44 {
  45 }
  46
  47 void __cpuinit local_timer_setup(unsigned int cpu)
  48 {
  49         struct clock_event_device *clk = &per_cpu(local_clockevent, cpu);
  50
  51         clk->name               = "dummy_timer";
  52         clk->features           = CLOCK_EVT_FEAT_ONESHOT |
  53                                   CLOCK_EVT_FEAT_PERIODIC |
  54                                   CLOCK_EVT_FEAT_DUMMY;
  55         clk->rating             = 400;
  56         clk->mult               = 1;
  57         clk->set_mode           = dummy_timer_set_mode;
  58         clk->broadcast          = smp_timer_broadcast;
  59         clk->cpumask            = cpumask_of(cpu);
  60
  61         clockevents_register_device(clk);
  62 }