arch/arm/lib/crt0_aarch64_efi.S

   1 /* SPDX-License-Identifier: GPL-2.0+ OR BSD-2-Clause */
   2 /*
   3  * crt0-efi-aarch64.S - PE/COFF header for aarch64 EFI applications
   4  *
   5  * Copright (C) 2014 Linaro Ltd. <ard.biesheuvel@linaro.org>
   6  *
   7  *
   8  * This file is taken and modified from the gnu-efi project.
   9  */
  10
  11 #include <asm-generic/pe.h>
  12
  13         .section        .text.head
  14
  15         /*
  16          * Magic "MZ" signature for PE/COFF
  17          */
  18         .globl  ImageBase
  19 ImageBase:
  20         .ascii  "MZ"
  21         .skip   58                              /* 'MZ' + pad + offset == 64 */
  22         .long   pe_header - ImageBase           /* Offset to the PE header */
  23 pe_header:
  24         .ascii  "PE"
  25         .short  0
  26 coff_header:
  27         .short  0xaa64                          /* AArch64 */
  28         .short  2                               /* nr_sections */
  29         .long   0                               /* TimeDateStamp */
  30         .long   0                               /* PointerToSymbolTable */
  31         .long   1                               /* NumberOfSymbols */
  32         .short  section_table - optional_header /* SizeOfOptionalHeader */
  33         /*
  34          * Characteristics: IMAGE_FILE_DEBUG_STRIPPED |
  35          * IMAGE_FILE_EXECUTABLE_IMAGE | IMAGE_FILE_LINE_NUMS_STRIPPED
  36          */
  37         .short  0x206
  38 optional_header:
  39         .short  0x20b                           /* PE32+ format */
  40         .byte   0x02                            /* MajorLinkerVersion */
  41         .byte   0x14                            /* MinorLinkerVersion */
  42         .long   _edata - _start                 /* SizeOfCode */
  43         .long   0                               /* SizeOfInitializedData */
  44         .long   0                               /* SizeOfUninitializedData */
  45         .long   _start - ImageBase              /* AddressOfEntryPoint */
  46         .long   _start - ImageBase              /* BaseOfCode */
  47
  48 extra_header_fields:
  49         .quad   0                               /* ImageBase */
  50         .long   0x20                            /* SectionAlignment */
  51         .long   0x8                             /* FileAlignment */
  52         .short  0                               /* MajorOperatingSystemVersion */
  53         .short  0                               /* MinorOperatingSystemVersion */
  54         .short  0                               /* MajorImageVersion */
  55         .short  0                               /* MinorImageVersion */
  56         .short  0                               /* MajorSubsystemVersion */
  57         .short  0                               /* MinorSubsystemVersion */
  58         .long   0                               /* Win32VersionValue */
  59
  60         .long   _edata - ImageBase              /* SizeOfImage */
  61
  62         /*
  63          * Everything before the kernel image is considered part of the header
  64          */
  65         .long   _start - ImageBase              /* SizeOfHeaders */
  66         .long   0                               /* CheckSum */
  67         .short  IMAGE_SUBSYSTEM_EFI_APPLICATION /* Subsystem */
  68         .short  0                               /* DllCharacteristics */
  69         .quad   0                               /* SizeOfStackReserve */
  70         .quad   0                               /* SizeOfStackCommit */
  71         .quad   0                               /* SizeOfHeapReserve */
  72         .quad   0                               /* SizeOfHeapCommit */
  73         .long   0                               /* LoaderFlags */
  74         .long   0x6                             /* NumberOfRvaAndSizes */
  75
  76         .quad   0                               /* ExportTable */
  77         .quad   0                               /* ImportTable */
  78         .quad   0                               /* ResourceTable */
  79         .quad   0                               /* ExceptionTable */
  80         .quad   0                               /* CertificationTable */
  81         .quad   0                               /* BaseRelocationTable */
  82
  83         /* Section table */
  84 section_table:
  85
  86         /*
  87          * The EFI application loader requires a relocation section
  88          * because EFI applications must be relocatable.  This is a
  89          * dummy section as far as we are concerned.
  90          */
  91         .ascii  ".reloc"
  92         .byte   0
  93         .byte   0                       /* end of 0 padding of section name */
  94         .long   0
  95         .long   0
  96         .long   0                       /* SizeOfRawData */
  97         .long   0                       /* PointerToRawData */
  98         .long   0                       /* PointerToRelocations */
  99         .long   0                       /* PointerToLineNumbers */
 100         .short  0                       /* NumberOfRelocations */
 101         .short  0                       /* NumberOfLineNumbers */
 102         .long   0x42100040              /* Characteristics (section flags) */
 103
 104
 105         .ascii  ".text"
 106         .byte   0
 107         .byte   0
 108         .byte   0                       /* end of 0 padding of section name */
 109         .long   _edata - _start         /* VirtualSize */
 110         .long   _start - ImageBase      /* VirtualAddress */
 111         .long   _edata - _start         /* SizeOfRawData */
 112         .long   _start - ImageBase      /* PointerToRawData */
 113
 114         .long   0               /* PointerToRelocations (0 for executables) */
 115         .long   0               /* PointerToLineNumbers (0 for executables) */
 116         .short  0               /* NumberOfRelocations  (0 for executables) */
 117         .short  0               /* NumberOfLineNumbers  (0 for executables) */
 118         .long   0xe0500020      /* Characteristics (section flags) */
 119
 120 _start:
 121         stp             x29, x30, [sp, #-32]!
 122         mov             x29, sp
 123
 124         stp             x0, x1, [sp, #16]
 125         mov             x2, x0
 126         mov             x3, x1
 127         adr             x0, ImageBase
 128         adrp            x1, _DYNAMIC
 129         add             x1, x1, #:lo12:_DYNAMIC
 130         bl              _relocate
 131         cbnz            x0, 0f
 132
 133         ldp             x0, x1, [sp, #16]
 134         bl              efi_main
 135
 136 0:      ldp             x29, x30, [sp], #32
 137         ret