arch/arm/lib/crt0_aarch64_efi.S

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