lock.h revision 1.12 
1/*	$NetBSD: lock.h,v 1.12 2007/09/10 11:34:08 skrll Exp $	*/
2
3/*-
4 * Copyright (c) 2000 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Jason R. Thorpe.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 * 3. All advertising materials mentioning features or use of this software
19 *    must display the following acknowledgement:
20 *	This product includes software developed by the NetBSD
21 *	Foundation, Inc. and its contributors.
22 * 4. Neither the name of The NetBSD Foundation nor the names of its
23 *    contributors may be used to endorse or promote products derived
24 *    from this software without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36 * POSSIBILITY OF SUCH DAMAGE.
37 */
38
39/*
40 * Machine-dependent spin lock operations.
41 */
42
43#ifndef _M68K_LOCK_H_
44#define	_M68K_LOCK_H_
45
46static __inline int
47__SIMPLELOCK_LOCKED_P(__cpu_simple_lock_t *__ptr)
48{
49	return *__ptr == __SIMPLELOCK_LOCKED;
50}
51
52static __inline int
53__SIMPLELOCK_UNLOCKED_P(__cpu_simple_lock_t *__ptr)
54{
55	return *__ptr == __SIMPLELOCK_UNLOCKED;
56}
57
58static __inline void
59__cpu_simple_lock_init(__cpu_simple_lock_t *alp)
60{
61
62	*alp = __SIMPLELOCK_UNLOCKED;
63}
64
65
66static __inline void
67__cpu_simple_lock_clear(__cpu_simple_lock_t *__ptr)
68{
69	*__ptr = __SIMPLELOCK_UNLOCKED;
70}
71
72static __inline void
73__cpu_simple_lock_set(__cpu_simple_lock_t *__ptr)
74{
75	*__ptr = __SIMPLELOCK_LOCKED;
76}
77
78static __inline void
79__cpu_simple_lock(__cpu_simple_lock_t *alp)
80{
81
82	__asm volatile(
83		"1:	tas	%0	\n"
84		"	jne	1b	\n"
85		: "=m" (*alp));
86}
87
88static __inline int
89__cpu_simple_lock_try(__cpu_simple_lock_t *alp)
90{
91	int __rv;
92
93	__asm volatile(
94		"	moveq	#1, %1	\n"
95		"	tas	%0	\n"
96		"	jeq	1f	\n"
97		"	moveq	#0, %1	\n"
98		"1:			\n"
99		: "=m" (*alp), "=d" (__rv));
100
101	return (__rv);
102}
103
104static __inline void
105__cpu_simple_unlock(__cpu_simple_lock_t *alp)
106{
107
108	*alp = __SIMPLELOCK_UNLOCKED;
109}
110
111static __inline void
112mb_read(void)
113{
114	__asm volatile("" : : : "memory");
115}
116
117static __inline void
118mb_write(void)
119{
120	__asm volatile("" : : : "memory");
121}
122
123static __inline void
124mb_memory(void)
125{
126	__asm volatile("" : : : "memory");
127}
128
129#endif /* _M68K_LOCK_H_ */
130