1 /* $NetBSD: lock.h,v 1.10 2022/02/13 13:41:26 riastradh 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 *
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 _ACORN32_LOCK_H_
33 #define _ACORN32_LOCK_H_
34
35 #include <sys/param.h>
36
37 #ifdef _KERNEL_OPT
38 #include "opt_multiprocessor.h"
39 #endif
40
41 #if defined(_HARDKERNEL) && defined(MULTIPROCESSOR)
42
43 #include <arm/cpufunc.h>
44
45 static __inline int
__swp(int __val,volatile unsigned char * __ptr)46 __swp(int __val, volatile unsigned char *__ptr)
47 {
48
49 __asm volatile("swpb %0, %1, [%2]"
50 : "=r" (__val) : "r" (__val), "r" (__ptr) : "memory");
51 return __val;
52 }
53
54 static __inline void __attribute__((__unused__))
__cpu_simple_lock_init(__cpu_simple_lock_t * alp)55 __cpu_simple_lock_init(__cpu_simple_lock_t *alp)
56 {
57
58 *alp = __SIMPLELOCK_UNLOCKED;
59 }
60
61 static __inline void __attribute__((__unused__))
__cpu_simple_lock(__cpu_simple_lock_t * alp)62 __cpu_simple_lock(__cpu_simple_lock_t *alp)
63 {
64
65 while (__swp(__SIMPLELOCK_LOCKED, alp) != __SIMPLELOCK_UNLOCKED)
66 continue;
67 cpu_idcache_wbinv_all();
68 }
69
70 static __inline int __attribute__((__unused__))
__cpu_simple_lock_try(__cpu_simple_lock_t * alp)71 __cpu_simple_lock_try(__cpu_simple_lock_t *alp)
72 {
73 int __result;
74
75 __result = __swp(__SIMPLELOCK_LOCKED, alp) == __SIMPLELOCK_UNLOCKED;
76 if (__result)
77 cpu_idcache_wbinv_all();
78 return __result;
79 }
80
81 static __inline void __attribute__((__unused__))
__cpu_simple_unlock(__cpu_simple_lock_t * alp)82 __cpu_simple_unlock(__cpu_simple_lock_t *alp)
83 {
84
85 __insn_barrier();
86 *alp = __SIMPLELOCK_UNLOCKED;
87 }
88
89 #else /* !(_HARDKERNEL && MULTIPROCESSOR) */
90 #include <arm/lock.h>
91 #endif /* !(_HARDKERNEL && MULTIPROCESSOR) */
92 #endif
93