arch/riscv/lib/crt0_riscv_efi.S

   1 /* SPDX-License-Identifier: GPL-2.0+ */
   2 /*
   3  * crt0-efi-riscv.S - PE/COFF header for RISC-V EFI applications
   4  *
   5  * Copright (C) 2014 Linaro Ltd. <ard.biesheuvel@linaro.org>
   6  * Copright (C) 2018 Alexander Graf <agraf@suse.de>
   7  *
   8  * This file is inspired by arch/arm/lib/crt0_aarch64_efi.S
   9  */
  10
  11 #include <asm-generic/pe.h>
  12
  13 #if __riscv_xlen == 64
  14 #define SIZE_LONG       8
  15 #define SAVE_LONG(reg, idx)     sd      reg, (idx*SIZE_LONG)(sp)
  16 #define LOAD_LONG(reg, idx)     ld      reg, (idx*SIZE_LONG)(sp)
  17 #define PE_MACHINE      IMAGE_FILE_MACHINE_RISCV64
  18 #define PE_MAGIC    IMAGE_NT_OPTIONAL_HDR64_MAGIC
  19 #else
  20 #define SIZE_LONG       4
  21 #define SAVE_LONG(reg, idx)     sw      reg, (idx*SIZE_LONG)(sp)
  22 #define LOAD_LONG(reg, idx)     lw      reg, (idx*SIZE_LONG)(sp)
  23 #define PE_MACHINE      IMAGE_FILE_MACHINE_RISCV32
  24 #define PE_MAGIC    IMAGE_NT_OPTIONAL_HDR32_MAGIC
  25 #endif
  26
  27
  28         .section        .text.head
  29
  30         /*
  31          * Magic "MZ" signature for PE/COFF
  32          */
  33         .globl  ImageBase
  34 ImageBase:
  35         .short  IMAGE_DOS_SIGNATURE             /* 'MZ' */
  36         .skip   46                              /* 'MZ' + pad + offset == 64 */
  37         .long   0x43534952                      /* Linux magic "RISCV */
  38         .long   0x00000056
  39         .long   0x05435352                      /* Linux magic2 "RSC\x05*/
  40         .long   pe_header - ImageBase           /* Offset to the PE header */
  41 pe_header:
  42         .long   IMAGE_NT_SIGNATURE              /* 'PE' */
  43 coff_header:
  44         .short  PE_MACHINE                      /* RISC-V 64/32-bit */
  45         .short  2                               /* nr_sections */
  46         .long   0                               /* TimeDateStamp */
  47         .long   0                               /* PointerToSymbolTable */
  48         .long   0                               /* NumberOfSymbols */
  49         .short  section_table - optional_header /* SizeOfOptionalHeader */
  50         /* Characteristics */
  51         .short  (IMAGE_FILE_EXECUTABLE_IMAGE | \
  52                  IMAGE_FILE_LINE_NUMS_STRIPPED | \
  53                  IMAGE_FILE_LOCAL_SYMS_STRIPPED | \
  54                  IMAGE_FILE_DEBUG_STRIPPED)
  55 optional_header:
  56         .short  PE_MAGIC                        /* PE32(+) format */
  57         .byte   0x02                            /* MajorLinkerVersion */
  58         .byte   0x14                            /* MinorLinkerVersion */
  59         .long   _edata - _start                 /* SizeOfCode */
  60         .long   0                               /* SizeOfInitializedData */
  61         .long   0                               /* SizeOfUninitializedData */
  62         .long   _start - ImageBase              /* AddressOfEntryPoint */
  63         .long   _start - ImageBase              /* BaseOfCode */
  64 #if __riscv_xlen == 32
  65         .long   0                               /* BaseOfData */
  66 #endif
  67
  68 extra_header_fields:
  69 #if __riscv_xlen == 32
  70         .long   0                               /* ImageBase */
  71 #else
  72         .quad   0                               /* ImageBase */
  73 #endif
  74         .long   0x200                           /* SectionAlignment */
  75         .long   0x200                           /* FileAlignment */
  76         .short  0                               /* MajorOperatingSystemVersion */
  77         .short  0                               /* MinorOperatingSystemVersion */
  78         .short  1                               /* MajorImageVersion */
  79         .short  0                               /* MinorImageVersion */
  80         .short  0                               /* MajorSubsystemVersion */
  81         .short  0                               /* MinorSubsystemVersion */
  82         .long   0                               /* Win32VersionValue */
  83
  84         .long   _edata - ImageBase              /* SizeOfImage */
  85
  86         /*
  87          * Everything before the kernel image is considered part of the header
  88          */
  89         .long   _start - ImageBase              /* SizeOfHeaders */
  90         .long   0                               /* CheckSum */
  91         .short  IMAGE_SUBSYSTEM_EFI_APPLICATION /* Subsystem */
  92         .short  0                               /* DllCharacteristics */
  93 #if __riscv_xlen == 32
  94         .long   0                               /* SizeOfStackReserve */
  95         .long   0                               /* SizeOfStackCommit */
  96         .long   0                               /* SizeOfHeapReserve */
  97         .long   0                               /* SizeOfHeapCommit */
  98 #else
  99         .quad   0                               /* SizeOfStackReserve */
 100         .quad   0                               /* SizeOfStackCommit */
 101         .quad   0                               /* SizeOfHeapReserve */
 102         .quad   0                               /* SizeOfHeapCommit */
 103 #endif
 104         .long   0                               /* LoaderFlags */
 105         .long   0x6                             /* NumberOfRvaAndSizes */
 106
 107         .quad   0                               /* ExportTable */
 108         .quad   0                               /* ImportTable */
 109         .quad   0                               /* ResourceTable */
 110         .quad   0                               /* ExceptionTable */
 111         .quad   0                               /* CertificationTable */
 112         .quad   0                               /* BaseRelocationTable */
 113
 114         /* Section table */
 115 section_table:
 116
 117         /*
 118          * The EFI application loader requires a relocation section
 119          * because EFI applications must be relocatable.  This is a
 120          * dummy section as far as we are concerned.
 121          */
 122         .ascii  ".reloc"
 123         .byte   0
 124         .byte   0                       /* end of 0 padding of section name */
 125         .long   0
 126         .long   0
 127         .long   0                       /* SizeOfRawData */
 128         .long   0                       /* PointerToRawData */
 129         .long   0                       /* PointerToRelocations */
 130         .long   0                       /* PointerToLineNumbers */
 131         .short  0                       /* NumberOfRelocations */
 132         .short  0                       /* NumberOfLineNumbers */
 133         .long   0x42100040              /* Characteristics (section flags) */
 134
 135
 136         .ascii  ".text"
 137         .byte   0
 138         .byte   0
 139         .byte   0                       /* end of 0 padding of section name */
 140         .long   _edata - _start         /* VirtualSize */
 141         .long   _start - ImageBase      /* VirtualAddress */
 142         .long   _edata - _start         /* SizeOfRawData */
 143         .long   _start - ImageBase      /* PointerToRawData */
 144
 145         .long   0               /* PointerToRelocations (0 for executables) */
 146         .long   0               /* PointerToLineNumbers (0 for executables) */
 147         .short  0               /* NumberOfRelocations  (0 for executables) */
 148         .short  0               /* NumberOfLineNumbers  (0 for executables) */
 149         .long   0xe0500020      /* Characteristics (section flags) */
 150
 151         .align  9
 152 _start:
 153         addi            sp, sp, -(SIZE_LONG * 3)
 154         SAVE_LONG(a0, 0)
 155         SAVE_LONG(a1, 1)
 156         SAVE_LONG(ra, 2)
 157
 158         lla             a0, ImageBase
 159         lla             a1, _DYNAMIC
 160         call            _relocate
 161         bne             a0, zero, 0f
 162
 163         LOAD_LONG(a1, 1)
 164         LOAD_LONG(a0, 0)
 165         call            efi_main
 166
 167         LOAD_LONG(ra, 2)
 168
 169 0:      addi            sp, sp, (SIZE_LONG * 3)
 170         ret