/*
 * Copyright (c) 2005 Martin Decky
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/** @addtogroup ppc32
 * @{
 */
/** @file
 */

#ifndef KERN_ppc32_ATOMIC_H_
#define KERN_ppc32_ATOMIC_H_

#include <trace.h>

NO_TRACE static inline void atomic_inc(atomic_t *val)
{
	atomic_count_t tmp;
	
	asm volatile (
		"1:\n"
		"	lwarx %[tmp], 0, %[count_ptr]\n"
		"	addic %[tmp], %[tmp], 1\n"
		"	stwcx. %[tmp], 0, %[count_ptr]\n"
		"	bne- 1b"
		: [tmp] "=&r" (tmp),
		  "=m" (val->count)
		: [count_ptr] "r" (&val->count),
		  "m" (val->count)
		: "cc"
	);
}

NO_TRACE static inline void atomic_dec(atomic_t *val)
{
	atomic_count_t tmp;
	
	asm volatile (
		"1:\n"
		"	lwarx %[tmp], 0, %[count_ptr]\n"
		"	addic %[tmp], %[tmp], -1\n"
		"	stwcx. %[tmp], 0, %[count_ptr]\n"
		"	bne- 1b"
		: [tmp] "=&r" (tmp),
		  "=m" (val->count)
		: [count_ptr] "r" (&val->count),
		  "m" (val->count)
		: "cc"
	);
}

NO_TRACE static inline atomic_count_t atomic_postinc(atomic_t *val)
{
	atomic_inc(val);
	return val->count - 1;
}

NO_TRACE static inline atomic_count_t atomic_postdec(atomic_t *val)
{
	atomic_dec(val);
	return val->count + 1;
}

NO_TRACE static inline atomic_count_t atomic_preinc(atomic_t *val)
{
	atomic_inc(val);
	return val->count;
}

NO_TRACE static inline atomic_count_t atomic_predec(atomic_t *val)
{
	atomic_dec(val);
	return val->count;
}

#endif

/** @}
 */