xref: /freebsd/usr.sbin/btxld/btx.h (revision e0c4386e)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 1998 Robert Nordier
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS
20  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
21  * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
22  * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
23  * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
24  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
25  * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
26  * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #ifndef _BTX_H_
30 #define _BTX_H_
31 
32 #include <sys/types.h>
33 
34 #define BTX_PGSIZE	0x1000		/* Page size */
35 #define BTX_PGBASE	0x5000		/* Start of page tables */
36 #define BTX_MAXCWR	0x3bc		/* Max. btx_pgctl adjustment */
37 
38 /*
39  * BTX image header.
40  */
41 struct btx_hdr {
42     uint8_t	btx_machid;		/* Machine ID */
43     uint8_t	btx_hdrsz;		/* Header size */
44     uint8_t	btx_magic[3];		/* Magic */
45     uint8_t	btx_majver;		/* Major version */
46     uint8_t	btx_minver;		/* Minor version */
47     uint8_t	btx_flags;		/* Flags */
48     uint16_t	btx_pgctl;		/* Paging control */
49     uint16_t	btx_textsz;		/* Text size */
50     uint32_t	btx_entry;		/* Client entry address */
51 };
52 
53 /* btx_machid */
54 #define BTX_I386	0xeb		/* Intel i386 or compatible */
55 
56 /* btx_magic */
57 #define BTX_MAG0	'B'
58 #define BTX_MAG1	'T'
59 #define BTX_MAG2	'X'
60 
61 /* btx_flags */
62 #define BTX_MAPONE	0x80		/* Start mapping at page 1 */
63 
64 #define BTX_MAPPED(btx) (((btx).btx_pgctl | (BTX_PGSIZE / 4 - 1)) + 1)
65 #define BTX_ORIGIN(btx) (BTX_PGBASE + BTX_MAPPED(btx) * 4)
66 #define BTX_ENTRY(btx)	(BTX_ORIGIN(btx) + 2 + (btx).btx_hdrsz)
67 
68 #endif /* !_BTX_H_ */
69