xref: /openbmc/linux/arch/arm/kernel/arch_timer.c (revision feac8c8b)
1 /*
2  *  linux/arch/arm/kernel/arch_timer.c
3  *
4  *  Copyright (C) 2011 ARM Ltd.
5  *  All Rights Reserved
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 #include <linux/init.h>
12 #include <linux/types.h>
13 #include <linux/errno.h>
14 
15 #include <asm/delay.h>
16 
17 #include <clocksource/arm_arch_timer.h>
18 
19 static unsigned long arch_timer_read_counter_long(void)
20 {
21 	return arch_timer_read_counter();
22 }
23 
24 static struct delay_timer arch_delay_timer;
25 
26 static void __init arch_timer_delay_timer_register(void)
27 {
28 	/* Use the architected timer for the delay loop. */
29 	arch_delay_timer.read_current_timer = arch_timer_read_counter_long;
30 	arch_delay_timer.freq = arch_timer_get_rate();
31 	register_current_timer_delay(&arch_delay_timer);
32 }
33 
34 int __init arch_timer_arch_init(void)
35 {
36         u32 arch_timer_rate = arch_timer_get_rate();
37 
38 	if (arch_timer_rate == 0)
39 		return -ENXIO;
40 
41 	arch_timer_delay_timer_register();
42 
43 	return 0;
44 }
45