LXR linux/arch/arm64/kernel/image.h

   1/*
   2 * Linker script macros to generate Image header fields.
   3 *
   4 * Copyright (C) 2014 ARM Ltd.
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License version 2 as
   8 * published by the Free Software Foundation.
   9 *
  10 * This program is distributed in the hope that it will be useful,
  11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 * GNU General Public License for more details.
  14 *
  15 * You should have received a copy of the GNU General Public License
  16 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17 */
  18#ifndef __ASM_IMAGE_H
  19#define __ASM_IMAGE_H
  20
  21#ifndef LINKER_SCRIPT
  22#error This file should only be included in vmlinux.lds.S
  23#endif
  24
  25/*
  26 * There aren't any ELF relocations we can use to endian-swap values known only
  27 * at link time (e.g. the subtraction of two symbol addresses), so we must get
  28 * the linker to endian-swap certain values before emitting them.
  29 */
  30#ifdef CONFIG_CPU_BIG_ENDIAN
  31#define DATA_LE64(data)                                 \
  32        ((((data) & 0x00000000000000ff) << 56) |        \
  33         (((data) & 0x000000000000ff00) << 40) |        \
  34         (((data) & 0x0000000000ff0000) << 24) |        \
  35         (((data) & 0x00000000ff000000) << 8)  |        \
  36         (((data) & 0x000000ff00000000) >> 8)  |        \
  37         (((data) & 0x0000ff0000000000) >> 24) |        \
  38         (((data) & 0x00ff000000000000) >> 40) |        \
  39         (((data) & 0xff00000000000000) >> 56))
  40#else
  41#define DATA_LE64(data) ((data) & 0xffffffffffffffff)
  42#endif
  43
  44#ifdef CONFIG_CPU_BIG_ENDIAN
  45#define __HEAD_FLAG_BE  1
  46#else
  47#define __HEAD_FLAG_BE  0
  48#endif
  49
  50#define __HEAD_FLAGS    (__HEAD_FLAG_BE << 0)
  51
  52/*
  53 * These will output as part of the Image header, which should be little-endian
  54 * regardless of the endianness of the kernel. While constant values could be
  55 * endian swapped in head.S, all are done here for consistency.
  56 */
  57#define HEAD_SYMBOLS                                            \
  58        _kernel_size_le         = DATA_LE64(_end - _text);      \
  59        _kernel_offset_le       = DATA_LE64(TEXT_OFFSET);       \
  60        _kernel_flags_le        = DATA_LE64(__HEAD_FLAGS);
  61
  62#endif /* __ASM_IMAGE_H */
  63