NetBSD/sys/arch/i386/stand/lib/getextmemx.c
drochner 2092d92ef2 New, optional, method to get size of extended memory.
It will be used for getextmem() if EXTENDED_MEMDETECT is defined.
Worked on all tested machines.
Thanks to all testers, especially Martin Husemann!
1997-08-14 15:22:00 +00:00

67 lines
2.4 KiB
C

/* $NetBSD: getextmemx.c,v 1.1 1997/08/14 15:22:00 drochner Exp $ */
/*
* Copyright (c) 1997
* Matthias Drochner. 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 acknowledgement:
* This product includes software developed for the NetBSD Project
* by Matthias Drochner.
* 4. The name of the author 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.
*
*/
/* Try 2 more fancy BIOS calls to get the size of extended
memory besides the classical int15/88, take maximum.
needs lowlevel parts from biosmemx.S and biosmem.S
*/
#include <lib/libsa/stand.h>
#include "libi386.h"
extern int getextmem2 __P((int*));
extern int getmementry __P((int, int*));
int getextmemx()
{
int buf[5], i;
int extmem = getextmem1();
if(!getextmem2(buf) && buf[0] <= 15 * 1024) {
int help = buf[0];
if(help == 15 * 1024)
help += buf[1] * 64;
if(extmem < help)
extmem = help;
}
for(i = 0; (i = getmementry(i, buf)) != 0;) {
if((buf[4] == 1 && buf[0] == 0x100000)
&& extmem < buf[2] / 1024)
extmem = buf[2] / 1024;
}
return(extmem);
}