/*      $NetBSD: biosdelay.S,v 1.4 2005/12/11 12:17:48 christos Exp $   */

/*
* Copyright (c) 1996, 1997
*      Perry E. Metzger.  All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
*    notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
*    notice, this list of conditions and the following disclaimer in the
*    documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
*    must display the following acknowledgements:
*      This product includes software developed for the NetBSD Project
*      by Perry E. Metzger.
* 4. The names of the authors may not be used to endorse or promote products
*    derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/

#include <machine/asm.h>

       .text

/*
* BIOS call "INT 15H Function 86H" to sleep for a set number of microseconds
*      Call with       %ah = 0x86
*                      %cx = time interval (high)
*                      %dx = time interval (low)
*      Return:
*              If error
*                      CF  = set
*              else
*                      CF  = clear
*/
ENTRY(delay)
       pushl   %ebp
       pushl   %ebx
       pushl   %esi
       pushl   %edi

       movw    20(%esp), %dx
       movw    22(%esp), %cx

       call    _C_LABEL(prot_to_real)
       .code16

       movb    $0x86, %ah
       int     $0x15
       setnc   %ah

       movb    %ah, %bl        # real_to_prot uses %eax

       calll   _C_LABEL(real_to_prot)
       .code32

       xorl    %eax, %eax
       movb    %bl, %al

       popl    %edi
       popl    %esi
       popl    %ebx
       popl    %ebp
       ret