image.h (2075B)
1/* SPDX-License-Identifier: GPL-2.0-only */ 2/* 3 * Linker script macros to generate Image header fields. 4 * 5 * Copyright (C) 2014 ARM Ltd. 6 */ 7#ifndef __ARM64_KERNEL_IMAGE_H 8#define __ARM64_KERNEL_IMAGE_H 9 10#ifndef LINKER_SCRIPT 11#error This file should only be included in vmlinux.lds.S 12#endif 13 14#include <asm/image.h> 15 16/* 17 * There aren't any ELF relocations we can use to endian-swap values known only 18 * at link time (e.g. the subtraction of two symbol addresses), so we must get 19 * the linker to endian-swap certain values before emitting them. 20 * 21 * Note that, in order for this to work when building the ELF64 PIE executable 22 * (for KASLR), these values should not be referenced via R_AARCH64_ABS64 23 * relocations, since these are fixed up at runtime rather than at build time 24 * when PIE is in effect. So we need to split them up in 32-bit high and low 25 * words. 26 */ 27#ifdef CONFIG_CPU_BIG_ENDIAN 28#define DATA_LE32(data) \ 29 ((((data) & 0x000000ff) << 24) | \ 30 (((data) & 0x0000ff00) << 8) | \ 31 (((data) & 0x00ff0000) >> 8) | \ 32 (((data) & 0xff000000) >> 24)) 33#else 34#define DATA_LE32(data) ((data) & 0xffffffff) 35#endif 36 37#define DEFINE_IMAGE_LE64(sym, data) \ 38 sym##_lo32 = DATA_LE32((data) & 0xffffffff); \ 39 sym##_hi32 = DATA_LE32((data) >> 32) 40 41#define __HEAD_FLAG(field) (__HEAD_FLAG_##field << \ 42 ARM64_IMAGE_FLAG_##field##_SHIFT) 43 44#ifdef CONFIG_CPU_BIG_ENDIAN 45#define __HEAD_FLAG_BE ARM64_IMAGE_FLAG_BE 46#else 47#define __HEAD_FLAG_BE ARM64_IMAGE_FLAG_LE 48#endif 49 50#define __HEAD_FLAG_PAGE_SIZE ((PAGE_SHIFT - 10) / 2) 51 52#define __HEAD_FLAG_PHYS_BASE 1 53 54#define __HEAD_FLAGS (__HEAD_FLAG(BE) | \ 55 __HEAD_FLAG(PAGE_SIZE) | \ 56 __HEAD_FLAG(PHYS_BASE)) 57 58/* 59 * These will output as part of the Image header, which should be little-endian 60 * regardless of the endianness of the kernel. While constant values could be 61 * endian swapped in head.S, all are done here for consistency. 62 */ 63#define HEAD_SYMBOLS \ 64 DEFINE_IMAGE_LE64(_kernel_size_le, _end - _text); \ 65 DEFINE_IMAGE_LE64(_kernel_flags_le, __HEAD_FLAGS); 66 67#endif /* __ARM64_KERNEL_IMAGE_H */