xref: /freebsd/usr.sbin/btxld/btx.h (revision 8ddb146abcdf061be9f2c0db7e391697dafad85c)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
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  * $FreeBSD$
29  */
30 
31 #ifndef _BTX_H_
32 #define _BTX_H_
33 
34 #include <sys/types.h>
35 
36 #define BTX_PGSIZE	0x1000		/* Page size */
37 #define BTX_PGBASE	0x5000		/* Start of page tables */
38 #define BTX_MAXCWR	0x3bc		/* Max. btx_pgctl adjustment */
39 
40 /*
41  * BTX image header.
42  */
43 struct btx_hdr {
44     uint8_t	btx_machid;		/* Machine ID */
45     uint8_t	btx_hdrsz;		/* Header size */
46     uint8_t	btx_magic[3];		/* Magic */
47     uint8_t	btx_majver;		/* Major version */
48     uint8_t	btx_minver;		/* Minor version */
49     uint8_t	btx_flags;		/* Flags */
50     uint16_t	btx_pgctl;		/* Paging control */
51     uint16_t	btx_textsz;		/* Text size */
52     uint32_t	btx_entry;		/* Client entry address */
53 };
54 
55 /* btx_machid */
56 #define BTX_I386	0xeb		/* Intel i386 or compatible */
57 
58 /* btx_magic */
59 #define BTX_MAG0	'B'
60 #define BTX_MAG1	'T'
61 #define BTX_MAG2	'X'
62 
63 /* btx_flags */
64 #define BTX_MAPONE	0x80		/* Start mapping at page 1 */
65 
66 #define BTX_MAPPED(btx) (((btx).btx_pgctl | (BTX_PGSIZE / 4 - 1)) + 1)
67 #define BTX_ORIGIN(btx) (BTX_PGBASE + BTX_MAPPED(btx) * 4)
68 #define BTX_ENTRY(btx)	(BTX_ORIGIN(btx) + 2 + (btx).btx_hdrsz)
69 
70 #endif /* !_BTX_H_ */
71