diff options
| author | Stephen Warren <swarren@nvidia.com> | 2018-01-03 14:31:51 -0700 |
|---|---|---|
| committer | Tom Warren <twarren@nvidia.com> | 2018-01-12 09:52:11 -0700 |
| commit | 8163faf952c467b01758b8a9a0dc8538e487aa9a (patch) | |
| tree | 2964e95d8dccd8367b2115876e7e481a32c2f0ff /arch/arm/include/asm/boot0-linux-kernel-header.h | |
| parent | f097532d279dd7a6ab2d579425d1318051ac1f8d (diff) | |
ARMv8: add optional Linux kernel image header
Allow placing a Linux kernel image header at the start of the U-Boot
binary. This is useful since the image header reports the amount of memory
(BSS and similar) that U-Boot needs to use, but that isn't part of the
binary size. This can be used by the code that loads U-Boot into memory to
determine where to load U-Boot, based on other users of memory.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>
Diffstat (limited to 'arch/arm/include/asm/boot0-linux-kernel-header.h')
| -rw-r--r-- | arch/arm/include/asm/boot0-linux-kernel-header.h | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/arch/arm/include/asm/boot0-linux-kernel-header.h b/arch/arm/include/asm/boot0-linux-kernel-header.h new file mode 100644 index 0000000000..ca28780daa --- /dev/null +++ b/arch/arm/include/asm/boot0-linux-kernel-header.h @@ -0,0 +1,49 @@ +/* + * (C) Copyright 2017 NVIDIA Corporation <www.nvidia.com> + * + * Derived from Linux kernel v4.14 files: + * + * arch/arm64/include/asm/assembler.h: + * Based on arch/arm/include/asm/assembler.h, arch/arm/mm/proc-macros.S + * Copyright (C) 1996-2000 Russell King + * Copyright (C) 2012 ARM Ltd. + * + * arch/arm64/kernel/head.S: + * Based on arch/arm/kernel/head.S + * Copyright (C) 1994-2002 Russell King + * Copyright (C) 2003-2012 ARM Ltd. + * Authors: Catalin Marinas <catalin.marinas@arm.com> + * Will Deacon <will.deacon@arm.com> + * + * arch/arm64/kernel/image.h: + * Copyright (C) 2014 ARM Ltd. + * + * SPDX-License-Identifier: GPL-2.0 + */ + + /* + * Emit a 64-bit absolute little endian symbol reference in a way that + * ensures that it will be resolved at build time, even when building a + * PIE binary. This requires cooperation from the linker script, which + * must emit the lo32/hi32 halves individually. + */ + .macro le64sym, sym + .long \sym\()_lo32 + .long \sym\()_hi32 + .endm + +.globl _start +_start: + /* + * DO NOT MODIFY. Image header expected by Linux boot-loaders. + */ + b reset /* branch to kernel start, magic */ + .long 0 /* reserved */ + le64sym _kernel_offset_le /* Image load offset from start of RAM, little-endian */ + le64sym _kernel_size_le /* Effective size of kernel image, little-endian */ + le64sym _kernel_flags_le /* Informative flags, little-endian */ + .quad 0 /* reserved */ + .quad 0 /* reserved */ + .quad 0 /* reserved */ + .ascii "ARM\x64" /* Magic number */ + .long 0 /* reserved */ |