lock.h revision 1.3 
1/*	$NetBSD: lock.h,v 1.3 2003/09/26 22:45:41 nathanw Exp $	*/
2
3/*-
4 * Copyright (c) 2000, 2001 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#ifndef _ACORN32_LOCK_H_
40#define _ACORN32_LOCK_H_
41
42#ifdef _KERNEL_OPT
43#include "opt_multiprocessor.h"
44#endif
45
46#if defined(_KERNEL) && defined(MULTIPROCESSOR)
47
48#include <arm/cpufunc.h>
49
50static __inline int
51__swp(int __val, __volatile int *__ptr)
52{
53
54	__asm __volatile("swp %0, %1, [%2]"
55	    : "=r" (__val) : "r" (__val), "r" (__ptr) : "memory");
56	return __val;
57}
58
59static __inline void __attribute__((__unused__))
60__cpu_simple_lock_init(__cpu_simple_lock_t *alp)
61{
62
63	*alp = __SIMPLELOCK_UNLOCKED;
64}
65
66static __inline void __attribute__((__unused__))
67__cpu_simple_lock(__cpu_simple_lock_t *alp)
68{
69
70	while (__swp(__SIMPLELOCK_LOCKED, alp) != __SIMPLELOCK_UNLOCKED)
71		continue;
72	cpu_idcache_wbinv_all();
73}
74
75static __inline int __attribute__((__unused__))
76__cpu_simple_lock_try(__cpu_simple_lock_t *alp)
77{
78	int __result;
79
80	__result = __swp(__SIMPLELOCK_LOCKED, alp) == __SIMPLELOCK_UNLOCKED;
81	if (__result)
82		cpu_idcache_wbinv_all();
83	return __result;
84}
85
86static __inline void __attribute__((__unused__))
87__cpu_simple_unlock(__cpu_simple_lock_t *alp)
88{
89
90	*alp = __SIMPLELOCK_UNLOCKED;
91}
92
93#else /* !(_KERNEL && MULTIPROCESSOR) */
94#include <arm/lock.h>
95#endif /* !(_KERNEL && MULTIPROCESSOR) */
96#endif
97