LXR linux/include/linux/flat.h

   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
  20struct 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
  63typedef 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 */
  80