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Greg Kroah-Hartmanb2441312017-11-01 15:07:57 +01001/* SPDX-License-Identifier: GPL-2.0 */
H. Peter Anvin1965aae2008-10-22 22:26:29 -07002#ifndef _ASM_X86_BIOS_EBDA_H
3#define _ASM_X86_BIOS_EBDA_H
Linus Torvalds1da177e2005-04-16 15:20:36 -07004
Akinobu Mita2c0903f2008-04-19 23:55:18 +09005#include <asm/io.h>
6
Linus Torvalds1da177e2005-04-16 15:20:36 -07007/*
Mike Waychisonf548ccd2011-03-14 23:58:50 -07008 * Returns physical address of EBDA. Returns 0 if there is no EBDA.
Linus Torvalds1da177e2005-04-16 15:20:36 -07009 */
10static inline unsigned int get_bios_ebda(void)
11{
Mike Waychisonf548ccd2011-03-14 23:58:50 -070012 /*
13 * There is a real-mode segmented pointer pointing to the
14 * 4K EBDA area at 0x40E.
15 */
Linus Torvalds1da177e2005-04-16 15:20:36 -070016 unsigned int address = *(unsigned short *)phys_to_virt(0x40E);
17 address <<= 4;
18 return address; /* 0 means none */
19}
20
Ingo Molnaredce2122016-07-21 09:53:52 +020021void reserve_bios_regions(void);
Huang, Ying0c51a962008-06-02 14:26:23 +080022
Ingo Molnar46eaa672008-10-12 15:06:29 +020023#ifdef CONFIG_X86_CHECK_BIOS_CORRUPTION
24/*
25 * This is obviously not a great place for this, but we want to be
26 * able to scatter it around anywhere in the kernel.
27 */
28void check_for_bios_corruption(void);
29void start_periodic_check_for_corruption(void);
30#else
31static inline void check_for_bios_corruption(void)
32{
33}
34
35static inline void start_periodic_check_for_corruption(void)
36{
37}
38#endif
39
H. Peter Anvin1965aae2008-10-22 22:26:29 -070040#endif /* _ASM_X86_BIOS_EBDA_H */