mirror of
				https://github.com/torvalds/linux.git
				synced 2025-11-04 10:40:15 +02:00 
			
		
		
		
	Kernel now supports chained power-off handlers. Use do_kernel_power_off() that invokes chained power-off handlers. It also invokes legacy pm_power_off() for now, which will be removed once all drivers will be converted to the new sys-off API. Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
		
			
				
	
	
		
			124 lines
		
	
	
	
		
			2.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			124 lines
		
	
	
	
		
			2.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
 | 
						|
 * This file is subject to the terms and conditions of the GNU General Public
 | 
						|
 * License.  See the file "COPYING" in the main directory of this archive
 | 
						|
 * for more details.
 | 
						|
 *
 | 
						|
 * Copyright (C) 2001, 06 by Ralf Baechle (ralf@linux-mips.org)
 | 
						|
 * Copyright (C) 2001 MIPS Technologies, Inc.
 | 
						|
 */
 | 
						|
#include <linux/kernel.h>
 | 
						|
#include <linux/export.h>
 | 
						|
#include <linux/pm.h>
 | 
						|
#include <linux/types.h>
 | 
						|
#include <linux/reboot.h>
 | 
						|
#include <linux/delay.h>
 | 
						|
 | 
						|
#include <asm/compiler.h>
 | 
						|
#include <asm/idle.h>
 | 
						|
#include <asm/mipsregs.h>
 | 
						|
#include <asm/reboot.h>
 | 
						|
 | 
						|
/*
 | 
						|
 * Urgs ...  Too many MIPS machines to handle this in a generic way.
 | 
						|
 * So handle all using function pointers to machine specific
 | 
						|
 * functions.
 | 
						|
 */
 | 
						|
void (*_machine_restart)(char *command);
 | 
						|
void (*_machine_halt)(void);
 | 
						|
void (*pm_power_off)(void);
 | 
						|
 | 
						|
EXPORT_SYMBOL(pm_power_off);
 | 
						|
 | 
						|
static void machine_hang(void)
 | 
						|
{
 | 
						|
	/*
 | 
						|
	 * We're hanging the system so we don't want to be interrupted anymore.
 | 
						|
	 * Any interrupt handlers that ran would at best be useless & at worst
 | 
						|
	 * go awry because the system isn't in a functional state.
 | 
						|
	 */
 | 
						|
	local_irq_disable();
 | 
						|
 | 
						|
	/*
 | 
						|
	 * Mask all interrupts, giving us a better chance of remaining in the
 | 
						|
	 * low power wait state.
 | 
						|
	 */
 | 
						|
	clear_c0_status(ST0_IM);
 | 
						|
 | 
						|
	while (true) {
 | 
						|
		if (cpu_has_mips_r) {
 | 
						|
			/*
 | 
						|
			 * We know that the wait instruction is supported so
 | 
						|
			 * make use of it directly, leaving interrupts
 | 
						|
			 * disabled.
 | 
						|
			 */
 | 
						|
			asm volatile(
 | 
						|
				".set	push\n\t"
 | 
						|
				".set	" MIPS_ISA_ARCH_LEVEL "\n\t"
 | 
						|
				"wait\n\t"
 | 
						|
				".set	pop");
 | 
						|
		} else if (cpu_wait) {
 | 
						|
			/*
 | 
						|
			 * Try the cpu_wait() callback. This isn't ideal since
 | 
						|
			 * it'll re-enable interrupts, but that ought to be
 | 
						|
			 * harmless given that they're all masked.
 | 
						|
			 */
 | 
						|
			cpu_wait();
 | 
						|
			local_irq_disable();
 | 
						|
		} else {
 | 
						|
			/*
 | 
						|
			 * We're going to burn some power running round the
 | 
						|
			 * loop, but we don't really have a choice. This isn't
 | 
						|
			 * a path we should expect to run for long during
 | 
						|
			 * typical use anyway.
 | 
						|
			 */
 | 
						|
		}
 | 
						|
 | 
						|
		/*
 | 
						|
		 * In most modern MIPS CPUs interrupts will cause the wait
 | 
						|
		 * instruction to graduate even when disabled, and in some
 | 
						|
		 * cases even when masked. In order to prevent a timer
 | 
						|
		 * interrupt from continuously taking us out of the low power
 | 
						|
		 * wait state, we clear any pending timer interrupt here.
 | 
						|
		 */
 | 
						|
		if (cpu_has_counter)
 | 
						|
			write_c0_compare(0);
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
void machine_restart(char *command)
 | 
						|
{
 | 
						|
	if (_machine_restart)
 | 
						|
		_machine_restart(command);
 | 
						|
 | 
						|
#ifdef CONFIG_SMP
 | 
						|
	preempt_disable();
 | 
						|
	smp_send_stop();
 | 
						|
#endif
 | 
						|
	do_kernel_restart(command);
 | 
						|
	mdelay(1000);
 | 
						|
	pr_emerg("Reboot failed -- System halted\n");
 | 
						|
	machine_hang();
 | 
						|
}
 | 
						|
 | 
						|
void machine_halt(void)
 | 
						|
{
 | 
						|
	if (_machine_halt)
 | 
						|
		_machine_halt();
 | 
						|
 | 
						|
#ifdef CONFIG_SMP
 | 
						|
	preempt_disable();
 | 
						|
	smp_send_stop();
 | 
						|
#endif
 | 
						|
	machine_hang();
 | 
						|
}
 | 
						|
 | 
						|
void machine_power_off(void)
 | 
						|
{
 | 
						|
	do_kernel_power_off();
 | 
						|
 | 
						|
#ifdef CONFIG_SMP
 | 
						|
	preempt_disable();
 | 
						|
	smp_send_stop();
 | 
						|
#endif
 | 
						|
	machine_hang();
 | 
						|
}
 |