1/*	$NetBSD: lock.h,v 1.15 2008/04/28 20:23:35 martin 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 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32/*
33 * Machine-dependent spin lock operations.
34 */
35
36#ifndef _SH3_LOCK_H_
37#define	_SH3_LOCK_H_
38
39static __inline void __cpu_simple_lock_init(__cpu_simple_lock_t *)
40	__attribute__((__unused__));
41static __inline void __cpu_simple_lock(__cpu_simple_lock_t *)
42	__attribute__((__unused__));
43static __inline int __cpu_simple_lock_try(__cpu_simple_lock_t *)
44	__attribute__((__unused__));
45static __inline void __cpu_simple_unlock(__cpu_simple_lock_t *)
46	__attribute__((__unused__));
47
48static __inline int
49__SIMPLELOCK_LOCKED_P(__cpu_simple_lock_t *__ptr)
50{
51	return *__ptr == __SIMPLELOCK_LOCKED;
52}
53
54static __inline int
55__SIMPLELOCK_UNLOCKED_P(__cpu_simple_lock_t *__ptr)
56{
57	return *__ptr == __SIMPLELOCK_UNLOCKED;
58}
59
60static __inline void
61__cpu_simple_lock_clear(__cpu_simple_lock_t *__ptr)
62{
63	*__ptr = __SIMPLELOCK_UNLOCKED;
64}
65
66static __inline void
67__cpu_simple_lock_set(__cpu_simple_lock_t *__ptr)
68{
69	*__ptr = __SIMPLELOCK_LOCKED;
70}
71
72static __inline void
73__cpu_simple_lock_init(__cpu_simple_lock_t *alp)
74{
75
76	*alp = __SIMPLELOCK_UNLOCKED;
77}
78
79static __inline void
80__cpu_simple_lock(__cpu_simple_lock_t *alp)
81{
82
83	 __asm volatile(
84		"1:	tas.b	@%0	\n"
85		"	bf	1b	\n"
86		: /* no outputs */
87		: "r" (alp)
88		: "cc", "memory");
89}
90
91static __inline int
92__cpu_simple_lock_try(__cpu_simple_lock_t *alp)
93{
94	int __rv;
95
96	__asm volatile(
97		"	tas.b	@%1	\n"
98		"	movt	%0	\n"
99		: "=r" (__rv)
100		: "r" (alp)
101		: "cc", "memory");
102
103	return (__rv);
104}
105
106static __inline void
107__cpu_simple_unlock(__cpu_simple_lock_t *alp)
108{
109
110	*alp = __SIMPLELOCK_UNLOCKED;
111}
112
113static __inline void
114mb_read(void)
115{
116	__asm volatile("" : : : "memory");
117}
118
119static __inline void
120mb_write(void)
121{
122	__asm volatile("" : : : "memory");
123}
124
125static __inline void
126mb_memory(void)
127{
128	__asm volatile("" : : : "memory");
129}
130
131#endif /* !_SH3_LOCK_H_ */
132