sys/arch/m68k/include/lock.h

   1 /*      $NetBSD: lock.h,v 1.13 2007/10/17 19:55:05 garbled 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(__cpu_simple_lock_t *__ptr)
  41 {
  42         return *__ptr == __SIMPLELOCK_LOCKED;
  43 }
  44
  45 static __inline int
  46 __SIMPLELOCK_UNLOCKED_P(__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_ */