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diff --git a/Documentation/riscv/boot-image-header.rst b/Documentation/riscv/boot-image-header.rst deleted file mode 100644 index d7752533865f..000000000000 --- a/Documentation/riscv/boot-image-header.rst +++ /dev/null @@ -1,62 +0,0 @@ -================================= -Boot image header in RISC-V Linux -================================= - -:Author: Atish Patra <atish.patra@wdc.com> -:Date: 20 May 2019 - -This document only describes the boot image header details for RISC-V Linux. - -TODO: - Write a complete booting guide. - -The following 64-byte header is present in decompressed Linux kernel image:: - - u32 code0; /* Executable code */ - u32 code1; /* Executable code */ - u64 text_offset; /* Image load offset, little endian */ - u64 image_size; /* Effective Image size, little endian */ - u64 flags; /* kernel flags, little endian */ - u32 version; /* Version of this header */ - u32 res1 = 0; /* Reserved */ - u64 res2 = 0; /* Reserved */ - u64 magic = 0x5643534952; /* Magic number, little endian, "RISCV" */ - u32 magic2 = 0x05435352; /* Magic number 2, little endian, "RSC\x05" */ - u32 res3; /* Reserved for PE COFF offset */ - -This header format is compliant with PE/COFF header and largely inspired from -ARM64 header. Thus, both ARM64 & RISC-V header can be combined into one common -header in future. - -Notes -===== - -- This header can also be reused to support EFI stub for RISC-V in future. EFI - specification needs PE/COFF image header in the beginning of the kernel image - in order to load it as an EFI application. In order to support EFI stub, - code0 should be replaced with "MZ" magic string and res3(at offset 0x3c) should - point to the rest of the PE/COFF header. - -- version field indicate header version number - - ========== ============= - Bits 0:15 Minor version - Bits 16:31 Major version - ========== ============= - - This preserves compatibility across newer and older version of the header. - The current version is defined as 0.2. - -- The "magic" field is deprecated as of version 0.2. In a future - release, it may be removed. This originally should have matched up - with the ARM64 header "magic" field, but unfortunately does not. - The "magic2" field replaces it, matching up with the ARM64 header. - -- In current header, the flags field has only one field. - - ===== ==================================== - Bit 0 Kernel endianness. 1 if BE, 0 if LE. - ===== ==================================== - -- Image size is mandatory for boot loader to load kernel image. Booting will - fail otherwise. |