diff options
| -rw-r--r-- | arch/i386/boot/mca.c | 43 |
1 files changed, 43 insertions, 0 deletions
diff --git a/arch/i386/boot/mca.c b/arch/i386/boot/mca.c new file mode 100644 index 00000000000..9b68bd1aef1 --- /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; +} |