From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Andr=C3=A9=20Fabian=20Silva=20Delgado?= Date: Wed, 5 Aug 2015 17:04:01 -0300 Subject: Initial import --- arch/x86/boot/mca.c | 38 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 38 insertions(+) create mode 100644 arch/x86/boot/mca.c (limited to 'arch/x86/boot/mca.c') diff --git a/arch/x86/boot/mca.c b/arch/x86/boot/mca.c new file mode 100644 index 000000000..a95a53114 --- /dev/null +++ b/arch/x86/boot/mca.c @@ -0,0 +1,38 @@ +/* -*- linux-c -*- ------------------------------------------------------- * + * + * Copyright (C) 1991, 1992 Linus Torvalds + * Copyright 2007 rPath, Inc. - All Rights Reserved + * Copyright 2009 Intel Corporation; author H. Peter Anvin + * + * 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) +{ + struct biosregs ireg, oreg; + u16 len; + + initregs(&ireg); + ireg.ah = 0xc0; + intcall(0x15, &ireg, &oreg); + + if (oreg.eflags & X86_EFLAGS_CF) + return -1; /* No MCA present */ + + set_fs(oreg.es); + len = rdfs16(oreg.bx); + + if (len > sizeof(boot_params.sys_desc_table)) + len = sizeof(boot_params.sys_desc_table); + + copy_from_fs(&boot_params.sys_desc_table, oreg.bx, len); + return 0; +} -- cgit v1.2.3