gnu-efi/gnuefi/crt0-efi-aarch64.S
Alfonso Sánchez-Beato 31a6aab44c Set NumberOfSymbols to zero
Acoording to what the spec says about the number of sybols [1]:

"This value should be zero for an image because COFF debugging
information is deprecated."

Changing as if not zero it causes problems to llvm-objcopy. This
affects only the architectures where COFF is not supported by objcopy
and where we build the PE header via assembly code.

[1] https://docs.microsoft.com/en-us/windows/win32/debug/pe-format
2021-07-29 11:38:16 +02:00

131 lines
3.9 KiB
ArmAsm

/*
* crt0-efi-aarch64.S - PE/COFF header for AArch64 EFI applications
*
* Copright (C) 2014 Linaro Ltd. <ard.biesheuvel@linaro.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice and this list of conditions, without modification.
* 2. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* Alternatively, this software may be distributed under the terms of the
* GNU General Public License as published by the Free Software Foundation;
* either version 2 of the License, or (at your option) any later version.
*/
.section .text.head
/*
* Magic "MZ" signature for PE/COFF
*/
.globl ImageBase
ImageBase:
.ascii "MZ"
.skip 58 // 'MZ' + pad + offset == 64
.long pe_header - ImageBase // Offset to the PE header.
pe_header:
.ascii "PE"
.short 0
coff_header:
.short 0xaa64 // AArch64
.short 2 // nr_sections
.long 0 // TimeDateStamp
.long 0 // PointerToSymbolTable
.long 0 // NumberOfSymbols
.short section_table - optional_header // SizeOfOptionalHeader
.short 0x206 // Characteristics.
// IMAGE_FILE_DEBUG_STRIPPED |
// IMAGE_FILE_EXECUTABLE_IMAGE |
// IMAGE_FILE_LINE_NUMS_STRIPPED
optional_header:
.short 0x20b // PE32+ format
.byte 0x02 // MajorLinkerVersion
.byte 0x14 // MinorLinkerVersion
.long _data - _start // SizeOfCode
.long _data_size // SizeOfInitializedData
.long 0 // SizeOfUninitializedData
.long _start - ImageBase // AddressOfEntryPoint
.long _start - ImageBase // BaseOfCode
extra_header_fields:
.quad 0 // ImageBase
.long 0x1000 // SectionAlignment
.long 0x200 // FileAlignment
.short 0 // MajorOperatingSystemVersion
.short 0 // MinorOperatingSystemVersion
.short 0 // MajorImageVersion
.short 0 // MinorImageVersion
.short 0 // MajorSubsystemVersion
.short 0 // MinorSubsystemVersion
.long 0 // Win32VersionValue
.long _edata - ImageBase // SizeOfImage
// Everything before the kernel image is considered part of the header
.long _start - ImageBase // SizeOfHeaders
.long 0 // CheckSum
.short EFI_SUBSYSTEM // Subsystem
.short 0 // DllCharacteristics
.quad 0 // SizeOfStackReserve
.quad 0 // SizeOfStackCommit
.quad 0 // SizeOfHeapReserve
.quad 0 // SizeOfHeapCommit
.long 0 // LoaderFlags
.long 0x6 // NumberOfRvaAndSizes
.quad 0 // ExportTable
.quad 0 // ImportTable
.quad 0 // ResourceTable
.quad 0 // ExceptionTable
.quad 0 // CertificationTable
.quad 0 // BaseRelocationTable
// Section table
section_table:
.ascii ".text\0\0\0"
.long _data - _start // VirtualSize
.long _start - ImageBase // VirtualAddress
.long _data - _start // SizeOfRawData
.long _start - ImageBase // PointerToRawData
.long 0 // PointerToRelocations (0 for executables)
.long 0 // PointerToLineNumbers (0 for executables)
.short 0 // NumberOfRelocations (0 for executables)
.short 0 // NumberOfLineNumbers (0 for executables)
.long 0x60000020 // Characteristics (section flags)
.ascii ".data\0\0\0"
.long _data_size // VirtualSize
.long _data - ImageBase // VirtualAddress
.long _data_size // SizeOfRawData
.long _data - ImageBase // PointerToRawData
.long 0 // PointerToRelocations (0 for executables)
.long 0 // PointerToLineNumbers (0 for executables)
.short 0 // NumberOfRelocations (0 for executables)
.short 0 // NumberOfLineNumbers (0 for executables)
.long 0xc0000040 // Characteristics (section flags)
.align 12
_start:
stp x29, x30, [sp, #-32]!
mov x29, sp
stp x0, x1, [sp, #16]
mov x2, x0
mov x3, x1
adr x0, ImageBase
adrp x1, _DYNAMIC
add x1, x1, #:lo12:_DYNAMIC
bl _relocate
cbnz x0, 0f
ldp x0, x1, [sp, #16]
bl efi_main
0: ldp x29, x30, [sp], #32
ret