From 3b53d3045bbb8ea3c9dce663b102eab0903817c5 Mon Sep 17 00:00:00 2001 From: "H. Peter Anvin" Date: Wed, 11 Jul 2007 12:18:49 -0700 Subject: MCA support for new x86 setup code MCA probing support for the new x86 setup code. This implements the same functionality as the assembly version. Signed-off-by: H. Peter Anvin Signed-off-by: Linus Torvalds --- arch/i386/boot/mca.c | 43 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 43 insertions(+) create mode 100644 arch/i386/boot/mca.c (limited to 'arch/i386/boot') diff --git a/arch/i386/boot/mca.c b/arch/i386/boot/mca.c new file mode 100644 index 000000000000..9b68bd1aef19 --- /dev/null +++ b/arch/i386/boot/mca.c @@ -0,0 +1,43 @@ +/* -*- 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. + * + * ----------------------------------------------------------------------- */ + +/* + * arch/i386/boot/mca.c + * + * 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" + : "=acdSDm" (err), "=acdSDm" (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; +} -- cgit v1.2.2