[deliverable/linux.git] / arch / arm / mach-msm / hotplug.c

/*
 *  Copyright (C) 2002 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/kernel.h>
#include <linux/errno.h>
#include <linux/smp.h>

#include <asm/cacheflush.h>
#include <asm/smp_plat.h>

#include "common.h"

static inline void cpu_enter_lowpower(void)
{
	/* Just flush the cache. Changing the coherency is not yet
	 * available on msm. */
	flush_cache_all();
}

static inline void cpu_leave_lowpower(void)
{
}

static inline void platform_do_lowpower(unsigned int cpu)
{
	/* Just enter wfi for now. TODO: Properly shut off the cpu. */
	for (;;) {
		/*
		 * here's the WFI
		 */
		asm("wfi"
		    :
		    :
		    : "memory", "cc");

		if (pen_release == cpu_logical_map(cpu)) {
			/*
			 * OK, proper wakeup, we're done
			 */
			break;
		}

		/*
		 * getting here, means that we have come out of WFI without
		 * having been woken up - this shouldn't happen
		 *
		 * The trouble is, letting people know about this is not really
		 * possible, since we are currently running incoherently, and
		 * therefore cannot safely call printk() or anything else
		 */
		pr_debug("CPU%u: spurious wakeup call\n", cpu);
	}
}

/*
 * platform-specific code to shutdown a CPU
 *
 * Called with IRQs disabled
 */
void __ref msm_cpu_die(unsigned int cpu)
{
	/*
	 * we're ready for shutdown now, so do it
	 */
	cpu_enter_lowpower();
	platform_do_lowpower(cpu);

	/*
	 * bring this CPU back into the world of cache
	 * coherency, and then restore interrupts
	 */
	cpu_leave_lowpower();
}
Commit	Line	Data
9f1890a5 JO	1	/*
	2	* Copyright (C) 2002 ARM Ltd.
	3	* All Rights Reserved
	4	*
	5	* This program is free software; you can redistribute it and/or modify
	6	* it under the terms of the GNU General Public License version 2 as
	7	* published by the Free Software Foundation.
	8	*/
	9	#include <linux/kernel.h>
	10	#include <linux/errno.h>
	11	#include <linux/smp.h>
	12
	13	#include <asm/cacheflush.h>
eb50439b	14	#include <asm/smp_plat.h>
9f1890a5	15
be2109e1	16	#include "common.h"
44ea349f	17
9f1890a5 JO	18	static inline void cpu_enter_lowpower(void)
	19	{
	20	/* Just flush the cache. Changing the coherency is not yet
	21	* available on msm. */
	22	flush_cache_all();
	23	}
	24
	25	static inline void cpu_leave_lowpower(void)
	26	{
	27	}
	28
	29	static inline void platform_do_lowpower(unsigned int cpu)
	30	{
	31	/* Just enter wfi for now. TODO: Properly shut off the cpu. */
	32	for (;;) {
	33	/*
	34	* here's the WFI
	35	*/
	36	asm("wfi"
	37	:
	38	:
	39	: "memory", "cc");
	40
1d3cfb34	41	if (pen_release == cpu_logical_map(cpu)) {
9f1890a5 JO	42	/*
	43	* OK, proper wakeup, we're done
	44	*/
	45	break;
	46	}
	47
	48	/*
	49	* getting here, means that we have come out of WFI without
	50	* having been woken up - this shouldn't happen
	51	*
	52	* The trouble is, letting people know about this is not really
	53	* possible, since we are currently running incoherently, and
	54	* therefore cannot safely call printk() or anything else
	55	*/
	56	pr_debug("CPU%u: spurious wakeup call\n", cpu);
	57	}
	58	}
	59
9f1890a5 JO	60	/*
	61	* platform-specific code to shutdown a CPU
	62	*
	63	* Called with IRQs disabled
	64	*/
44ea349f	65	void __ref msm_cpu_die(unsigned int cpu)
9f1890a5 JO	66	{
	67	/*
	68	* we're ready for shutdown now, so do it
	69	*/
	70	cpu_enter_lowpower();
	71	platform_do_lowpower(cpu);
	72
	73	/*
	74	* bring this CPU back into the world of cache
	75	* coherency, and then restore interrupts
	76	*/
	77	cpu_leave_lowpower();
	78	}