/*
 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * The contents of this file constitute Original Code as defined in and
 * are subject to the Apple Public Source License Version 1.1 (the
 * "License").  You may not use this file except in compliance with the
 * License.  Please obtain a copy of the License at
 * http://www.apple.com/publicsource and read it before using this file.
 * 
 * This Original Code and all software distributed under the License are
 * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
 * License for the specific language governing rights and limitations
 * under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */
 /*
 * Copyright (c) 1997-1998 Apple Computer, Inc.
 *
 *
 * HISTORY
 *
 * sdouglas  22 Oct 97 - first checked in from DriverServices
 * sdouglas  28 Jul 98 - start IOKit
 */

#include <architecture/ppc/asm_help.h>

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;
; ENTRY		functionName
;
; Assembly directives to begin an exported function.
;
; Takes: functionName - name of the exported function
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

.macro ENTRY
	.text
	.align		2
	.globl		$0
$0:
.endmacro

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

/*
int OSCompareAndSwap( UInt32 oldVal, UInt32 newVal, UInt32 * addr )
*/


	ENTRY	_OSCompareAndSwap

	lwarx	r6,	0,r5		/* CEMV10 */
.L_CASretry:
	lwarx	r6,	0,r5
	cmpw	r6,	r3
	bne-	.L_CASfail
	stwcx.	r4,	0,r5
	bne-	.L_CASretry
	isync
	li	r3,	1
	blr
.L_CASfail:
	li	r3,	0
	blr


/*
SInt32	OSDecrementAtomic(SInt32 * value)
*/
	ENTRY	_OSDecrementAtomic
	mr	r4, r3
	li	r3, -1
	b	_OSAddAtomic

/*
SInt32	OSIncrementAtomic(SInt32 * value)
*/

	ENTRY	_OSIncrementAtomic
	mr	r4, r3
	li	r3, 1

/*
SInt32	OSAddAtomic(SInt32 amount, SInt32 * value)
*/

	ENTRY	_OSAddAtomic

	mr	r5,r3				/* Save the increment */
	lwarx	r3,0,r4				/* CEMV10 */

.L_AAretry:
	lwarx	r3, 0, r4			/* Grab the area value */
	add	r6, r3, r5			/* Add the value */
	stwcx.	r6, 0, r4			/* Try to save the new value */
	bne-	.L_AAretry			/* Didn't get it, try again... */
	blr					/* Return the original value */