m68020.h

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/* Copyright (C) 1994 Free Software Foundation, Inc.
   Contributed by Joel Sherrill ([e-mail]),
     On-Line Applications Research Corporation.
 
This file is part of the GNU C Library.
 
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
 
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
Library General Public License for more details.
 
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB.  If
not, write to the Free Software Foundation, Inc., 675 Mass Ave,
Cambridge, MA 02139, USA.  */

/*  m68020.h
 *
 *  This file contains macros which are used to access MC68020 
 *  registers which are not addressable by C.  These are
 *  useful when developing the board specific support.
 */

#ifndef m68020_h__
#define m68020_h__

typedef void ( *mc68020_isr )( void );

#define disable_intr( level ) \
  { (level) = 0; \
    asm volatile ( "movew   %%sr,%0 ; \
                    orw     #0x0700,%%sr" \
                    : "=d" ((level)) : "0" ((level)) ); \
  }

#define enable_intr( level ) \
  { asm volatile ( "movew   %0,%%sr " \
                       : "=d" ((level)) : "0" ((level)) ); \
  }

#define flash_intr( level ) \
  { asm volatile ( "movew   %0,%%sr ; \
                    orw     #0x0700,%%sr" \
                       : "=d" ((level)) : "0" ((level)) ); \
  }

#define get_vbr( vbr ) \
  { (vbr) = 0; \
    asm volatile ( "movec   %%vbr,%0 " \
                       : "=a" (vbr) : "0" (vbr) ); \
  }

#define set_vbr( vbr ) \
  { register mc68020_isr *_vbr= (mc68020_isr *)(vbr); \
    asm volatile ( "movec   %0,%%vbr " \
                       : "=a" (_vbr) : "0" (_vbr) ); \
  }

#define enable_caching() \
  { register unsigned int _ctl=0x01; \
    asm volatile ( "movec   %0,%%cacr" \
                       : "=d" (_ctl) : "0" (_ctl) ); \
  }

#define delay( microseconds ) \
  { register unsigned int _delay=(microseconds); \
    register unsigned int _tmp=123; \
    asm volatile( "0: \
                     nbcd      %0 ; \
                     nbcd      %0 ; \
                     dbf       %1,0 " \
                  : "=d" (_tmp), "=d" (_delay) \
                  : "0"  (_tmp), "1"  (_delay) ); \
  }

#define enable_tracing() 
#define cause_intr( X ) 
#define clear_intr( X ) 

extern mc68020_isr     M68Kvec[];   /* vector table address */

#endif
/* end of include file */