gnu-efi/gnuefi/crt0-efi-mips64el.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

189 lines
4.7 KiB
ArmAsm

/*
* crt0-efi-mips64el.S - PE/COFF header for MIPS64 EFI applications
*
* Copright (C) 2014 Linaro Ltd. <ard.biesheuvel@linaro.org>
* Copright (C) 2017 Heiher <r@hev.cc>
*
* 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 0x166 // MIPS little endian
.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 _edata - _start // SizeOfCode
.long 0 // SizeOfInitializedData
.long 0 // SizeOfUninitializedData
.long _start - ImageBase // AddressOfEntryPoint
.long _start - ImageBase // BaseOfCode
extra_header_fields:
.quad 0 // ImageBase
.long 0x20 // SectionAlignment
.long 0x8 // 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:
/*
* The EFI application loader requires a relocation section
* because EFI applications must be relocatable. This is a
* dummy section as far as we are concerned.
*/
.ascii ".reloc"
.byte 0
.byte 0 // end of 0 padding of section name
.long 0
.long 0
.long 0 // SizeOfRawData
.long 0 // PointerToRawData
.long 0 // PointerToRelocations
.long 0 // PointerToLineNumbers
.short 0 // NumberOfRelocations
.short 0 // NumberOfLineNumbers
.long 0x42100040 // Characteristics (section flags)
.ascii ".text"
.byte 0
.byte 0
.byte 0 // end of 0 padding of section name
.long _edata - _start // VirtualSize
.long _start - ImageBase // VirtualAddress
.long _edata - _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 0xe0500020 // Characteristics (section flags)
.set push
.set noreorder
.align 4
.globl _start
.ent _start
.type _start, @function
_start:
daddiu $sp, -32
sd $ra, ($sp)
// Get pc & gp
.align 3
bal 1f
sd $gp, 8($sp)
_pc:
.dword _gp
.dword _DYNAMIC
.dword _relocate
1:
// pc in ra
ld $gp, ($ra)
dli $t0, _pc
dsubu $gp, $t0
daddu $gp, $ra
sd $a0, 16($sp)
sd $a1, 24($sp)
// a2: ImageHandle
move $a2, $a0
// a3: SystemTable
move $a3, $a1
// a0: ImageBase
dli $t1, ImageBase - _pc
daddu $a0, $ra, $t1
// a1: DynamicSection
ld $t1, 8($ra)
dsubu $t1, $t0
daddu $a1, $ra, $t1
// call _relocate
ld $t1, 16($ra)
dsubu $t1, $t0
daddu $t9, $ra, $t1
jalr $t9
nop
bnez $v0, 1b
nop
// a0: ImageHandle
ld $a0, 16($sp)
// call efi_main
dla $t9, efi_main
jalr $t9
// a1: SystemTable
ld $a1, 24($sp)
1:
ld $gp, 8($sp)
ld $ra, ($sp)
jr $ra
daddiu $sp, 32
.end _start
.set pop