linux/arch/arm/kernel/arch_timer.c
Stephen Boyd 65cd4f6c99 arch_timer: Move to generic sched_clock framework
Register with the generic sched_clock framework now that it
supports 64 bits. This fixes two problems with the current
sched_clock support for machines using the architected timers.
First off, we don't subtract the start value from subsequent
sched_clock calls so we can potentially start off with
sched_clock returning gigantic numbers. Second, there is no
support for suspend/resume handling so problems such as discussed
in 6a4dae5 (ARM: 7565/1: sched: stop sched_clock() during
suspend, 2012-10-23) can happen without this patch. Finally, it
allows us to move the sched_clock setup into drivers clocksource
out of the arch ports.

Cc: Christopher Covington <cov@codeaurora.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-10-09 16:54:10 -07:00

45 lines
1.0 KiB
C

/*
* linux/arch/arm/kernel/arch_timer.c
*
* Copyright (C) 2011 ARM Ltd.
* All Rights Reserved
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/init.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <asm/delay.h>
#include <clocksource/arm_arch_timer.h>
static unsigned long arch_timer_read_counter_long(void)
{
return arch_timer_read_counter();
}
static struct delay_timer arch_delay_timer;
static void __init arch_timer_delay_timer_register(void)
{
/* Use the architected timer for the delay loop. */
arch_delay_timer.read_current_timer = arch_timer_read_counter_long;
arch_delay_timer.freq = arch_timer_get_rate();
register_current_timer_delay(&arch_delay_timer);
}
int __init arch_timer_arch_init(void)
{
u32 arch_timer_rate = arch_timer_get_rate();
if (arch_timer_rate == 0)
return -ENXIO;
arch_timer_delay_timer_register();
return 0;
}