drivers/clocksource/dummy_timer.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  *  linux/drivers/clocksource/dummy_timer.c
   4  *
   5  *  Copyright (C) 2013 ARM Ltd.
   6  *  All Rights Reserved
   7  */
   8 #include <linux/clockchips.h>
   9 #include <linux/cpu.h>
  10 #include <linux/init.h>
  11 #include <linux/percpu.h>
  12 #include <linux/cpumask.h>
  13
  14 static DEFINE_PER_CPU(struct clock_event_device, dummy_timer_evt);
  15
  16 static int dummy_timer_starting_cpu(unsigned int cpu)
  17 {
  18         struct clock_event_device *evt = per_cpu_ptr(&dummy_timer_evt, cpu);
  19
  20         evt->name       = "dummy_timer";
  21         evt->features   = CLOCK_EVT_FEAT_PERIODIC |
  22                           CLOCK_EVT_FEAT_ONESHOT |
  23                           CLOCK_EVT_FEAT_DUMMY;
  24         evt->rating     = 100;
  25         evt->cpumask    = cpumask_of(cpu);
  26
  27         clockevents_register_device(evt);
  28         return 0;
  29 }
  30
  31 static int __init dummy_timer_register(void)
  32 {
  33         return cpuhp_setup_state(CPUHP_AP_DUMMY_TIMER_STARTING,
  34                                  "clockevents/dummy_timer:starting",
  35                                  dummy_timer_starting_cpu, NULL);
  36 }
  37 early_initcall(dummy_timer_register);