linux-stable-rt/arch/openrisc/kernel/idle.c

78 lines
1.8 KiB
C

/*
* OpenRISC idle.c
*
* Linux architectural port borrowing liberally from similar works of
* others. All original copyrights apply as per the original source
* declaration.
*
* Modifications for the OpenRISC architecture:
* Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
* Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
* Idle daemon for or32. Idle daemon will handle any action
* that needs to be taken when the system becomes idle.
*/
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/smp.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/ptrace.h>
#include <linux/slab.h>
#include <linux/tick.h>
#include <asm/pgtable.h>
#include <asm/uaccess.h>
#include <asm/system.h>
#include <asm/io.h>
#include <asm/processor.h>
#include <asm/mmu.h>
#include <asm/cache.h>
#include <asm/pgalloc.h>
void (*powersave) (void) = NULL;
static inline void pm_idle(void)
{
barrier();
}
void cpu_idle(void)
{
set_thread_flag(TIF_POLLING_NRFLAG);
/* endless idle loop with no priority at all */
while (1) {
tick_nohz_stop_sched_tick(1);
while (!need_resched()) {
check_pgt_cache();
rmb();
clear_thread_flag(TIF_POLLING_NRFLAG);
local_irq_disable();
/* Don't trace irqs off for idle */
stop_critical_timings();
if (!need_resched() && powersave != NULL)
powersave();
start_critical_timings();
local_irq_enable();
set_thread_flag(TIF_POLLING_NRFLAG);
}
tick_nohz_restart_sched_tick();
preempt_enable_no_resched();
schedule();
preempt_disable();
}
}