xref: /netbsd-src/sys/arch/sh3/include/lock.h (revision 5b84b3983f71fd20a534cfa5d1556623a8aaa717)
1 /*	$NetBSD: lock.h,v 1.6 2003/09/26 22:46:01 nathanw Exp $	*/
2 
3 /*-
4  * Copyright (c) 2002 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Gregory McGarry.
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 _SH3_LOCK_H_
44 #define	_SH3_LOCK_H_
45 
46 static __inline void __cpu_simple_lock_init __P((__cpu_simple_lock_t *))
47 	__attribute__((__unused__));
48 static __inline void __cpu_simple_lock __P((__cpu_simple_lock_t *))
49 	__attribute__((__unused__));
50 static __inline int __cpu_simple_lock_try __P((__cpu_simple_lock_t *))
51 	__attribute__((__unused__));
52 static __inline void __cpu_simple_unlock __P((__cpu_simple_lock_t *))
53 	__attribute__((__unused__));
54 
55 static __inline void
56 __cpu_simple_lock_init(__cpu_simple_lock_t *alp)
57 {
58 
59 	*alp = __SIMPLELOCK_UNLOCKED;
60 }
61 
62 static __inline void
63 __cpu_simple_lock(__cpu_simple_lock_t *alp)
64 {
65 
66 	 __asm __volatile(
67 		"1:	tas.b	%0	\n"
68 		"	bf	1b	\n"
69 		: "=m" (*alp));
70 }
71 
72 static __inline int
73 __cpu_simple_lock_try(__cpu_simple_lock_t *alp)
74 {
75 	int __rv;
76 
77 	__asm __volatile(
78 		"	tas.b	%0	\n"
79 		"	mov	#0, %1	\n"
80 		"	rotcl	%1	\n"
81 		: "=m" (*alp), "=r" (__rv));
82 
83 	return (__rv);
84 }
85 
86 static __inline void
87 __cpu_simple_unlock(__cpu_simple_lock_t *alp)
88 {
89 
90 	*alp = __SIMPLELOCK_UNLOCKED;
91 }
92 
93 #endif /* !_SH3_LOCK_H_ */
94