linux-sg2042/arch/x86/boot/mca.c

42 lines
918 B
C

/* -*- linux-c -*- ------------------------------------------------------- *
*
* Copyright (C) 1991, 1992 Linus Torvalds
* Copyright 2007 rPath, Inc. - All Rights Reserved
*
* This file is part of the Linux kernel, and is made available under
* the terms of the GNU General Public License version 2.
*
* ----------------------------------------------------------------------- */
/*
* Get the MCA system description table
*/
#include "boot.h"
int query_mca(void)
{
u8 err;
u16 es, bx, len;
asm("pushw %%es ; "
"int $0x15 ; "
"setc %0 ; "
"movw %%es, %1 ; "
"popw %%es"
: "=acd" (err), "=acdSD" (es), "=b" (bx)
: "a" (0xc000));
if (err)
return -1; /* No MCA present */
set_fs(es);
len = rdfs16(bx);
if (len > sizeof(boot_params.sys_desc_table))
len = sizeof(boot_params.sys_desc_table);
copy_from_fs(&boot_params.sys_desc_table, bx, len);
return 0;
}