1 /* $NetBSD: lock.h,v 1.15 2017/09/17 00:01:07 christos Exp $ */ 2 3 /*- 4 * Copyright (c) 2000 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 /* 33 * Machine-dependent spin lock operations. 34 */ 35 36 #ifndef _M68K_LOCK_H_ 37 #define _M68K_LOCK_H_ 38 39 static __inline int 40 __SIMPLELOCK_LOCKED_P(const __cpu_simple_lock_t *__ptr) 41 { 42 return *__ptr == __SIMPLELOCK_LOCKED; 43 } 44 45 static __inline int 46 __SIMPLELOCK_UNLOCKED_P(const __cpu_simple_lock_t *__ptr) 47 { 48 return *__ptr == __SIMPLELOCK_UNLOCKED; 49 } 50 51 static __inline void 52 __cpu_simple_lock_init(__cpu_simple_lock_t *alp) 53 { 54 55 *alp = __SIMPLELOCK_UNLOCKED; 56 } 57 58 59 static __inline void 60 __cpu_simple_lock_clear(__cpu_simple_lock_t *__ptr) 61 { 62 *__ptr = __SIMPLELOCK_UNLOCKED; 63 } 64 65 static __inline void 66 __cpu_simple_lock_set(__cpu_simple_lock_t *__ptr) 67 { 68 *__ptr = __SIMPLELOCK_LOCKED; 69 } 70 71 static __inline void 72 __cpu_simple_lock(__cpu_simple_lock_t *alp) 73 { 74 75 __asm volatile( 76 "1: tas %0 \n" 77 " jne 1b \n" 78 : "=m" (*alp)); 79 } 80 81 static __inline int 82 __cpu_simple_lock_try(__cpu_simple_lock_t *alp) 83 { 84 int __rv; 85 86 __asm volatile( 87 " moveq #1, %1 \n" 88 " tas %0 \n" 89 " jeq 1f \n" 90 " moveq #0, %1 \n" 91 "1: \n" 92 : "=m" (*alp), "=d" (__rv)); 93 94 return (__rv); 95 } 96 97 static __inline void 98 __cpu_simple_unlock(__cpu_simple_lock_t *alp) 99 { 100 101 *alp = __SIMPLELOCK_UNLOCKED; 102 } 103 104 static __inline void 105 mb_read(void) 106 { 107 __asm volatile("" : : : "memory"); 108 } 109 110 static __inline void 111 mb_write(void) 112 { 113 __asm volatile("" : : : "memory"); 114 } 115 116 static __inline void 117 mb_memory(void) 118 { 119 __asm volatile("" : : : "memory"); 120 } 121 122 #endif /* _M68K_LOCK_H_ */ 123