locks.h

00001 /* Locks -- Operations to protect critical sections
00002    Copyright (C) 2000, 2001, 2002 Free Software Foundation, Inc.
00003    Written by Stephane Carrez (stcarrez@nerim.fr)       
00004 
00005 This file is free software; you can redistribute it and/or modify it
00006 under the terms of the GNU General Public License as published by the
00007 Free Software Foundation; either version 2, or (at your option) any
00008 later version.
00009 
00010 In addition to the permissions in the GNU General Public License, the
00011 Free Software Foundation gives you unlimited permission to link the
00012 compiled version of this file with other programs, and to distribute
00013 those programs without any restriction coming from the use of this
00014 file.  (The General Public License restrictions do apply in other
00015 respects; for example, they cover modification of the file, and
00016 distribution when not linked into another program.)
00017 
00018 This file is distributed in the hope that it will be useful, but
00019 WITHOUT ANY WARRANTY; without even the implied warranty of
00020 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00021 General Public License for more details.
00022 
00023 You should have received a copy of the GNU General Public License
00024 along with this program; see the file COPYING.  If not, write to
00025 the Free Software Foundation, 59 Temple Place - Suite 330,
00026 Boston, MA 02111-1307, USA.  */
00027 
00028 #ifndef _M68HC11_LOCKS_H
00029 #define _M68HC11_LOCKS_H
00030 
00081   
00090 static __inline__ unsigned short
00091 lock (void)
00092 {
00093   unsigned short mask;
00094 
00095   __asm__ __volatile__ ("tpa\n\tsei" : "=d"(mask));
00096   return mask;
00097 }
00098 
00105 static __inline__ void
00106 unlock (void)
00107 {
00108   __asm__ __volatile__ ("cli");
00109 }
00110 
00117 static __inline__ void
00118 restore (unsigned short mask)
00119 {
00120   __asm__ __volatile__ ("tap" : : "d"(mask));
00121 }
00122 
00134 static __inline__ void
00135 interruption_point (void)
00136 {
00137   __asm__ __volatile__ ("cli\n\t"
00138                         "nop\n\t"
00139                         "sei");  
00140 }
00141 
00144 #endif