1/*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2020 Mitchell Horne <mhorne@FreeBSD.org> 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 * 27 * $FreeBSD$ 28 */ 29 30#include <machine/asm.h> 31 32/* 33 * We need to be a PE32+ file for EFI. On some architectures we can use 34 * objcopy to create the correct file, however on RISC-V we need to do 35 * it ourselves. 36 */ 37 38#define IMAGE_FILE_MACHINE_RISCV64 0x5064 39 40#define IMAGE_SCN_CNT_CODE 0x00000020 41#define IMAGE_SCN_CNT_INITIALIZED_DATA 0x00000040 42#define IMAGE_SCN_MEM_DISCARDABLE 0x02000000 43#define IMAGE_SCN_MEM_EXECUTE 0x20000000 44#define IMAGE_SCN_MEM_READ 0x40000000 45 46 .section .peheader,"a" 47efi_start: 48 /* The MS-DOS Stub, only used to get the offset of the COFF header */ 49 .ascii "MZ" 50 .short 0 51 .space 0x38 52 .long pe_sig - efi_start 53 54 /* The PE32 Signature. Needs to be 8-byte aligned */ 55 .align 3 56pe_sig: 57 .ascii "PE" 58 .short 0 59coff_head: 60 .short IMAGE_FILE_MACHINE_RISCV64 /* RISC-V 64 file */ 61 .short 2 /* 2 Sections */ 62 .long 0 /* Timestamp */ 63 .long 0 /* No symbol table */ 64 .long 0 /* No symbols */ 65 .short section_table - optional_header /* Optional header size */ 66 .short 0 /* Characteristics TODO: Fill in */ 67 68optional_header: 69 .short 0x020b /* PE32+ (64-bit addressing) */ 70 .byte 0 /* Major linker version */ 71 .byte 0 /* Minor linker version */ 72 .long _edata - _end_header /* Code size */ 73 .long 0 /* No initialized data */ 74 .long 0 /* No uninitialized data */ 75 .long _start - efi_start /* Entry point */ 76 .long _end_header - efi_start /* Start of code */ 77 78optional_windows_header: 79 .quad 0 /* Image base */ 80 .long 32 /* Section Alignment */ 81 .long 8 /* File alignment */ 82 .short 0 /* Major OS version */ 83 .short 0 /* Minor OS version */ 84 .short 0 /* Major image version */ 85 .short 0 /* Minor image version */ 86 .short 0 /* Major subsystem version */ 87 .short 0 /* Minor subsystem version */ 88 .long 0 /* Win32 version */ 89 .long _edata - efi_start /* Image size */ 90 .long _end_header - efi_start /* Header size */ 91 .long 0 /* Checksum */ 92 .short 0xa /* Subsystem (EFI app) */ 93 .short 0 /* DLL Characteristics */ 94 .quad 0 /* Stack reserve */ 95 .quad 0 /* Stack commit */ 96 .quad 0 /* Heap reserve */ 97 .quad 0 /* Heap commit */ 98 .long 0 /* Loader flags */ 99 .long 6 /* Number of RVAs */ 100 101 /* RVAs: */ 102 .quad 0 103 .quad 0 104 .quad 0 105 .quad 0 106 .quad 0 107 .quad 0 108 109section_table: 110 /* We need a .reloc section for EFI */ 111 .ascii ".reloc" 112 .byte 0 113 .byte 0 /* Pad to 8 bytes */ 114 .long 0 /* Virtual size */ 115 .long 0 /* Virtual address */ 116 .long 0 /* Size of raw data */ 117 .long 0 /* Pointer to raw data */ 118 .long 0 /* Pointer to relocations */ 119 .long 0 /* Pointer to line numbers */ 120 .short 0 /* Number of relocations */ 121 .short 0 /* Number of line numbers */ 122 .long (IMAGE_SCN_CNT_INITIALIZED_DATA | IMAGE_SCN_MEM_READ | \ 123 IMAGE_SCN_MEM_DISCARDABLE) /* Characteristics */ 124 125 /* The contents of the loader */ 126 .ascii ".text" 127 .byte 0 128 .byte 0 129 .byte 0 /* Pad to 8 bytes */ 130 .long _edata - _end_header /* Virtual size */ 131 .long _end_header - efi_start /* Virtual address */ 132 .long _edata - _end_header /* Size of raw data */ 133 .long _end_header - efi_start /* Pointer to raw data */ 134 .long 0 /* Pointer to relocations */ 135 .long 0 /* Pointer to line numbers */ 136 .short 0 /* Number of relocations */ 137 .short 0 /* Number of line numbers */ 138 .long (IMAGE_SCN_CNT_CODE | IMAGE_SCN_MEM_EXECUTE | \ 139 IMAGE_SCN_MEM_READ) /* Characteristics */ 140_end_header: 141 142 .text 143 .globl _start 144_start: 145 /* Save the boot params to the stack */ 146 addi sp, sp, -16 147 sd a0, 0(sp) 148 sd a1, 8(sp) 149 150 /* Zero the BSS */ 151 lla t0, __bss_start 152 lla t1, __bss_end 153 1541: sd zero, 0(t0) 155 addi t0, t0, 8 156 bltu t0, t1, 1b 157 158 lla a0, ImageBase 159 lla a1, _DYNAMIC 160 call _C_LABEL(self_reloc) 161 162 ld a1, 8(sp) 163 ld a0, 0(sp) 164 tail _C_LABEL(efi_main) 165 166 /* NOTREACHED */ 1672: wfi 168 j 2b 169