1 /* $NetBSD: atomic.h,v 1.3 2010/02/21 01:46:35 darran Exp $ */
2
3 /*-
4 * Copyright (c) 2009 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Andrew Doran.
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 #ifndef _CDDL_SYS_ATOMIC_H_
33 #define _CDDL_SYS_ATOMIC_H_
34
35 #include_next <sys/atomic.h>
36
37 #define casptr(_a, _b, _c) \
38 atomic_cas_ptr((volatile uint64_t *) _a, _b, _c);
39
40
41
42 static __inline void
atomic_or_8(volatile uint8_t * ptr,uint8_t val)43 atomic_or_8(volatile uint8_t *ptr, uint8_t val)
44 {
45 uint32_t mask;
46
47 #if _BYTE_ORDER == _LITTLE_ENDIAN
48 switch ((uintptr_t)ptr & 3) {
49 case 0:
50 mask = (uint32_t)val;
51 break;
52 case 1:
53 mask = (uint32_t)val << 8;
54 break;
55 case 2:
56 mask = (uint32_t)val << 16;
57 break;
58 case 3:
59 mask = (uint32_t)val << 24;
60 break;
61 }
62 #elif _BYTE_ORDER == _BIG_ENDIAN
63 switch ((uintptr_t)ptr & 3) {
64 case 3:
65 mask = (uint32_t)val;
66 break;
67 case 2:
68 mask = (uint32_t)val << 8;
69 break;
70 case 1:
71 mask = (uint32_t)val << 16;
72 break;
73 case 0:
74 mask = (uint32_t)val << 24;
75 break;
76 }
77 #else
78 #error What byte order?
79 #endif
80
81 atomic_or_32((uint32_t *)((uintptr_t)ptr & (uintptr_t)~3ULL), mask);
82 }
83
84 #endif /* _CDDL_SYS_ATOMIC_H */
85