diff options
| author | Yuval Adam <_@yuv.al> | 2017-08-30 08:25:59 +0000 |
|---|---|---|
| committer | Yuval Adam <_@yuv.al> | 2017-08-30 08:25:59 +0000 |
| commit | 8e4bff4cab0ddac6060645b0715210484d02ff40 (patch) | |
| tree | 3a5c3024371a04692a3a6d9974d001cdff8ebf84 /arch/x86/boot/mca.c | |
Diffstat (limited to 'arch/x86/boot/mca.c')
| -rw-r--r-- | arch/x86/boot/mca.c | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/arch/x86/boot/mca.c b/arch/x86/boot/mca.c new file mode 100644 index 00000000..a95a5311 --- /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; +} |
