1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * Copyright (C) 2002-2003 David McCullough <davidm@snapgear.com>
4 * Copyright (C) 1998 Kenneth Albanowski <kjahds@kjahds.com>
5 * The Silver Hammer Group, Ltd.
6 *
7 * This file provides the definitions and structures needed to
8 * support uClinux flat-format executables.
9 */
10 #ifndef _LINUX_FLAT_H
11 #define _LINUX_FLAT_H
12
13 #define FLAT_VERSION 0x00000004L
14
15 /*
16 * To make everything easier to port and manage cross platform
17 * development, all fields are in network byte order.
18 */
19
20 struct flat_hdr {
21 char magic[4];
22 __be32 rev; /* version (as above) */
23 __be32 entry; /* Offset of first executable instruction
24 with text segment from beginning of file */
25 __be32 data_start; /* Offset of data segment from beginning of
26 file */
27 __be32 data_end; /* Offset of end of data segment from beginning
28 of file */
29 __be32 bss_end; /* Offset of end of bss segment from beginning
30 of file */
31
32 /* (It is assumed that data_end through bss_end forms the bss segment.) */
33
34 __be32 stack_size; /* Size of stack, in bytes */
35 __be32 reloc_start; /* Offset of relocation records from beginning of
36 file */
37 __be32 reloc_count; /* Number of relocation records */
38 __be32 flags;
39 __be32 build_date; /* When the program/library was built */
40 __u32 filler[5]; /* Reservered, set to zero */
41 };
42
43 #define FLAT_FLAG_RAM 0x0001 /* load program entirely into RAM */
44 #define FLAT_FLAG_GOTPIC 0x0002 /* program is PIC with GOT */
45 #define FLAT_FLAG_GZIP 0x0004 /* all but the header is compressed */
46 #define FLAT_FLAG_GZDATA 0x0008 /* only data/relocs are compressed (for XIP) */
47 #define FLAT_FLAG_KTRACE 0x0010 /* output useful kernel trace for debugging */
48
49 /*
50 * While it would be nice to keep this header clean, users of older
51 * tools still need this support in the kernel. So this section is
52 * purely for compatibility with old tool chains.
53 *
54 * DO NOT make changes or enhancements to the old format please, just work
55 * with the format above, except to fix bugs with old format support.
56 */
57
58 #define OLD_FLAT_VERSION 0x00000002L
59 #define OLD_FLAT_RELOC_TYPE_TEXT 0
60 #define OLD_FLAT_RELOC_TYPE_DATA 1
61 #define OLD_FLAT_RELOC_TYPE_BSS 2
62
63 typedef union {
64 u32 value;
65 struct {
66 #if defined(__LITTLE_ENDIAN_BITFIELD) || \
67 (defined(mc68000) && !defined(CONFIG_COLDFIRE))
68 s32 offset : 30;
69 u32 type : 2;
70 # elif defined(__BIG_ENDIAN_BITFIELD)
71 u32 type : 2;
72 s32 offset : 30;
73 # else
74 # error "Unknown bitfield order for flat files."
75 # endif
76 } reloc;
77 } flat_v2_reloc_t;
78
79 #endif /* _LINUX_FLAT_H */