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	 2dfb34edfe
			
		
	
	
		2dfb34edfe
		
	
	
	
	
		
			
			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
		
	
	
	
	
	
| /*
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|  * This file is subject to the terms and conditions of the GNU General Public
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|  * License.  See the file "COPYING" in the main directory of this archive
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|  * for more details.
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|  *
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|  * Copyright (C) 2001, 06 by Ralf Baechle (ralf@linux-mips.org)
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|  * Copyright (C) 2001 MIPS Technologies, Inc.
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|  */
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| #include <linux/kernel.h>
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| #include <linux/export.h>
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| #include <linux/pm.h>
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| #include <linux/types.h>
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| #include <linux/reboot.h>
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| #include <linux/delay.h>
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| 
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| #include <asm/compiler.h>
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| #include <asm/idle.h>
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| #include <asm/mipsregs.h>
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| #include <asm/reboot.h>
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| 
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| /*
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|  * Urgs ...  Too many MIPS machines to handle this in a generic way.
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|  * So handle all using function pointers to machine specific
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|  * functions.
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|  */
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| void (*_machine_restart)(char *command);
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| void (*_machine_halt)(void);
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| void (*pm_power_off)(void);
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| 
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| EXPORT_SYMBOL(pm_power_off);
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| 
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| static void machine_hang(void)
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| {
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| 	/*
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| 	 * We're hanging the system so we don't want to be interrupted anymore.
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| 	 * Any interrupt handlers that ran would at best be useless & at worst
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| 	 * go awry because the system isn't in a functional state.
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| 	 */
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| 	local_irq_disable();
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| 
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| 	/*
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| 	 * Mask all interrupts, giving us a better chance of remaining in the
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| 	 * low power wait state.
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| 	 */
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| 	clear_c0_status(ST0_IM);
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| 
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| 	while (true) {
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| 		if (cpu_has_mips_r) {
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| 			/*
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| 			 * We know that the wait instruction is supported so
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| 			 * make use of it directly, leaving interrupts
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| 			 * disabled.
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| 			 */
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| 			asm volatile(
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| 				".set	push\n\t"
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| 				".set	" MIPS_ISA_ARCH_LEVEL "\n\t"
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| 				"wait\n\t"
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| 				".set	pop");
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| 		} else if (cpu_wait) {
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| 			/*
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| 			 * Try the cpu_wait() callback. This isn't ideal since
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| 			 * it'll re-enable interrupts, but that ought to be
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| 			 * harmless given that they're all masked.
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| 			 */
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| 			cpu_wait();
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| 			local_irq_disable();
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| 		} else {
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| 			/*
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| 			 * We're going to burn some power running round the
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| 			 * loop, but we don't really have a choice. This isn't
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| 			 * a path we should expect to run for long during
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| 			 * typical use anyway.
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| 			 */
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| 		}
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| 
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| 		/*
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| 		 * In most modern MIPS CPUs interrupts will cause the wait
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| 		 * instruction to graduate even when disabled, and in some
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| 		 * cases even when masked. In order to prevent a timer
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| 		 * interrupt from continuously taking us out of the low power
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| 		 * wait state, we clear any pending timer interrupt here.
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| 		 */
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| 		if (cpu_has_counter)
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| 			write_c0_compare(0);
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| 	}
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| }
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| 
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| void machine_restart(char *command)
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| {
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| 	if (_machine_restart)
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| 		_machine_restart(command);
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| 
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| #ifdef CONFIG_SMP
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| 	preempt_disable();
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| 	smp_send_stop();
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| #endif
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| 	do_kernel_restart(command);
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| 	mdelay(1000);
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| 	pr_emerg("Reboot failed -- System halted\n");
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| 	machine_hang();
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| }
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| 
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| void machine_halt(void)
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| {
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| 	if (_machine_halt)
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| 		_machine_halt();
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| 
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| #ifdef CONFIG_SMP
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| 	preempt_disable();
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| 	smp_send_stop();
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| #endif
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| 	machine_hang();
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| }
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| 
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| void machine_power_off(void)
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| {
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| 	do_kernel_power_off();
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| 
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| #ifdef CONFIG_SMP
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| 	preempt_disable();
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| 	smp_send_stop();
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| #endif
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| 	machine_hang();
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| }
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