1 /* $NetBSD: lock.h,v 1.2 2002/10/07 23:23:53 bjh21 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 50 typedef __volatile int __cpu_simple_lock_t; 51 52 #define __SIMPLELOCK_LOCKED 1 53 #define __SIMPLELOCK_UNLOCKED 0 54 55 static __inline int 56 __swp(int __val, __volatile int *__ptr) 57 { 58 59 __asm __volatile("swp %0, %1, [%2]" 60 : "=r" (__val) : "r" (__val), "r" (__ptr) : "memory"); 61 return __val; 62 } 63 64 static __inline void __attribute__((__unused__)) 65 __cpu_simple_lock_init(__cpu_simple_lock_t *alp) 66 { 67 68 *alp = __SIMPLELOCK_UNLOCKED; 69 } 70 71 static __inline void __attribute__((__unused__)) 72 __cpu_simple_lock(__cpu_simple_lock_t *alp) 73 { 74 75 while (__swp(__SIMPLELOCK_LOCKED, alp) != __SIMPLELOCK_UNLOCKED) 76 continue; 77 cpu_idcache_wbinv_all(); 78 } 79 80 static __inline int __attribute__((__unused__)) 81 __cpu_simple_lock_try(__cpu_simple_lock_t *alp) 82 { 83 int __result; 84 85 __result = __swp(__SIMPLELOCK_LOCKED, alp) == __SIMPLELOCK_UNLOCKED; 86 if (__result) 87 cpu_idcache_wbinv_all(); 88 return __result; 89 } 90 91 static __inline void __attribute__((__unused__)) 92 __cpu_simple_unlock(__cpu_simple_lock_t *alp) 93 { 94 95 *alp = __SIMPLELOCK_UNLOCKED; 96 } 97 98 #else /* !(_KERNEL && MULTIPROCESSOR) */ 99 #include <arm/lock.h> 100 #endif /* !(_KERNEL && MULTIPROCESSOR) */ 101 #endif 102