1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * (C) Copyright 2017 NVIDIA Corporation <www.nvidia.com> 4 * 5 * Derived from Linux kernel v4.14 files: 6 * 7 * arch/arm64/include/asm/assembler.h: 8 * Based on arch/arm/include/asm/assembler.h, arch/arm/mm/proc-macros.S 9 * Copyright (C) 1996-2000 Russell King 10 * Copyright (C) 2012 ARM Ltd. 11 * 12 * arch/arm64/kernel/head.S: 13 * Based on arch/arm/kernel/head.S 14 * Copyright (C) 1994-2002 Russell King 15 * Copyright (C) 2003-2012 ARM Ltd. 16 * Authors: Catalin Marinas <catalin.marinas@arm.com> 17 * Will Deacon <will.deacon@arm.com> 18 * 19 * arch/arm64/kernel/image.h: 20 * Copyright (C) 2014 ARM Ltd. 21 */ 22 23 /* 24 * There aren't any ELF relocations we can use to endian-swap values known only 25 * at link time (e.g. the subtraction of two symbol addresses), so we must get 26 * the linker to endian-swap certain values before emitting them. 27 * 28 * Note that, in order for this to work when building the ELF64 PIE executable 29 * (for KASLR), these values should not be referenced via R_AARCH64_ABS64 30 * relocations, since these are fixed up at runtime rather than at build time 31 * when PIE is in effect. So we need to split them up in 32-bit high and low 32 * words. 33 */ 34 #ifdef CONFIG_CPU_BIG_ENDIAN 35 #define DATA_LE32(data) \ 36 ((((data) & 0x000000ff) << 24) | \ 37 (((data) & 0x0000ff00) << 8) | \ 38 (((data) & 0x00ff0000) >> 8) | \ 39 (((data) & 0xff000000) >> 24)) 40 #else 41 #define DATA_LE32(data) ((data) & 0xffffffff) 42 #endif 43 44 #define DEFINE_IMAGE_LE64(sym, data) \ 45 sym##_lo32 = DATA_LE32((data) & 0xffffffff); \ 46 sym##_hi32 = DATA_LE32((data) >> 32) 47 48 #define __MAX(a, b) (((a) > (b)) ? (a) : (b)) 49 #define __CODE_DATA_SIZE (__bss_start - _start) 50 #define __BSS_SIZE (__bss_end - __bss_start) 51 #ifdef CONFIG_INIT_SP_RELATIVE 52 #define __MAX_EXTRA_RAM_USAGE __MAX(__BSS_SIZE, CONFIG_SYS_INIT_SP_BSS_OFFSET) 53 #else 54 #define __MAX_EXTRA_RAM_USAGE __BSS_SIZE 55 #endif 56 #define __MEM_USAGE (__CODE_DATA_SIZE + __MAX_EXTRA_RAM_USAGE) 57 58 #ifdef CONFIG_CPU_BIG_ENDIAN 59 #define __HEAD_FLAG_BE 1 60 #else 61 #define __HEAD_FLAG_BE 0 62 #endif 63 64 #define __HEAD_FLAG_PAGE_SIZE 1 /* 4K hard-coded */ 65 66 #define __HEAD_FLAG_PHYS_BASE 1 67 68 #define __HEAD_FLAGS ((__HEAD_FLAG_BE << 0) | \ 69 (__HEAD_FLAG_PAGE_SIZE << 1) | \ 70 (__HEAD_FLAG_PHYS_BASE << 3)) 71 72 #define TEXT_OFFSET (CONFIG_SYS_TEXT_BASE - \ 73 CONFIG_LNX_KRNL_IMG_TEXT_OFFSET_BASE) 74 75 /* 76 * These will output as part of the Image header, which should be little-endian 77 * regardless of the endianness of the kernel. While constant values could be 78 * endian swapped in head.S, all are done here for consistency. 79 */ 80 #define HEAD_SYMBOLS \ 81 DEFINE_IMAGE_LE64(_kernel_size_le, __MEM_USAGE); \ 82 DEFINE_IMAGE_LE64(_kernel_offset_le, TEXT_OFFSET); \ 83 DEFINE_IMAGE_LE64(_kernel_flags_le, __HEAD_FLAGS); 84 85 HEAD_SYMBOLS 86