xref: /netbsd-src/sys/arch/m68k/include/lock.h (revision 7fa608457b817eca6e0977b37f758ae064f3c99c)
1 /*	$NetBSD: lock.h,v 1.13 2007/10/17 19:55:05 garbled 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 
46 static __inline int
47 __SIMPLELOCK_LOCKED_P(__cpu_simple_lock_t *__ptr)
48 {
49 	return *__ptr == __SIMPLELOCK_LOCKED;
50 }
51 
52 static __inline int
53 __SIMPLELOCK_UNLOCKED_P(__cpu_simple_lock_t *__ptr)
54 {
55 	return *__ptr == __SIMPLELOCK_UNLOCKED;
56 }
57 
58 static __inline void
59 __cpu_simple_lock_init(__cpu_simple_lock_t *alp)
60 {
61 
62 	*alp = __SIMPLELOCK_UNLOCKED;
63 }
64 
65 
66 static __inline void
67 __cpu_simple_lock_clear(__cpu_simple_lock_t *__ptr)
68 {
69 	*__ptr = __SIMPLELOCK_UNLOCKED;
70 }
71 
72 static __inline void
73 __cpu_simple_lock_set(__cpu_simple_lock_t *__ptr)
74 {
75 	*__ptr = __SIMPLELOCK_LOCKED;
76 }
77 
78 static __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 
88 static __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 
104 static __inline void
105 __cpu_simple_unlock(__cpu_simple_lock_t *alp)
106 {
107 
108 	*alp = __SIMPLELOCK_UNLOCKED;
109 }
110 
111 static __inline void
112 mb_read(void)
113 {
114 	__asm volatile("" : : : "memory");
115 }
116 
117 static __inline void
118 mb_write(void)
119 {
120 	__asm volatile("" : : : "memory");
121 }
122 
123 static __inline void
124 mb_memory(void)
125 {
126 	__asm volatile("" : : : "memory");
127 }
128 
129 #endif /* _M68K_LOCK_H_ */
130