/* $OpenBSD: start.S,v 1.4 2022/12/08 01:25:44 guenther Exp $ */ /*- * Copyright (c) 2014, 2015 Andrew Turner * All rights reserved. * * 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, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * $FreeBSD: head/sys/boot/efi/loader/arch/arm/start.S 282727 2015-05-10 13:24:26Z ian $ */ #include <machine/asm.h> /* * We need to be a PE32 file for EFI. On some architectures we can use * objcopy to create the correct file, however on arm we need to do * it ourselves. */ #define IMAGE_FILE_MACHINE_ARM 0x01c2 #define IMAGE_SCN_CNT_CODE 0x00000020 #define IMAGE_SCN_CNT_INITIALIZED_DATA 0x00000040 #define IMAGE_SCN_MEM_DISCARDABLE 0x02000000 #define IMAGE_SCN_MEM_EXECUTE 0x20000000 #define IMAGE_SCN_MEM_READ 0x40000000 .section .peheader, "a" efi_start: /* The MS-DOS Stub, only used to get the offset of the COFF header */ .ascii "MZ" .short 0 .space 0x38 .long pe_sig - efi_start /* The PE32 Signature. Needs to be 8-byte aligned */ .align 3 pe_sig: .ascii "PE" .short 0 coff_head: .short IMAGE_FILE_MACHINE_ARM /* ARM file */ .short 2 /* 2 Sections */ .long 0 /* Timestamp */ .long 0 /* No symbol table */ .long 0 /* No symbols */ .short section_table - optional_header /* Optional header size */ .short 0 /* Characteristics TODO: Fill in */ optional_header: .short 0x010b /* PE32 (32-bit addressing) */ .byte 0 /* Major linker version */ .byte 0 /* Minor linker version */ .long _edata - _end_header /* Code size */ .long 0 /* No initialized data */ .long 0 /* No uninitialized data */ .long _start - efi_start /* Entry point */ .long _end_header - efi_start /* Start of code */ .long 0 /* Start of data */ optional_windows_header: .long 0 /* Image base */ .long 32 /* Section Alignment */ .long 8 /* File alignment */ .short 0 /* Major OS version */ .short 0 /* Minor OS version */ .short 0 /* Major image version */ .short 0 /* Minor image version */ .short 0 /* Major subsystem version */ .short 0 /* Minor subsystem version */ .long 0 /* Win32 version */ .long _edata - efi_start /* Image size */ .long _end_header - efi_start /* Header size */ .long 0 /* Checksum */ .short 0xa /* Subsystem (EFI app) */ .short 0 /* DLL Characteristics */ .long 0 /* Stack reserve */ .long 0 /* Stack commit */ .long 0 /* Heap reserve */ .long 0 /* Heap commit */ .long 0 /* Loader flags */ .long 6 /* Number of RVAs */ /* RVAs: */ .quad 0 .quad 0 .quad 0 .quad 0 .quad 0 .quad 0 section_table: /* We need a .reloc section for EFI */ .ascii ".reloc" .byte 0 .byte 0 /* Pad to 8 bytes */ .long 0 /* Virtual size */ .long 0 /* Virtual address */ .long 0 /* Size of raw data */ .long 0 /* Pointer to raw data */ .long 0 /* Pointer to relocations */ .long 0 /* Pointer to line numbers */ .short 0 /* Number of relocations */ .short 0 /* Number of line numbers */ .long (IMAGE_SCN_CNT_INITIALIZED_DATA | IMAGE_SCN_MEM_READ | \ IMAGE_SCN_MEM_DISCARDABLE) /* Characteristics */ /* The contents of the loader */ .ascii ".text" .byte 0 .byte 0 .byte 0 /* Pad to 8 bytes */ .long _edata - _end_header /* Virtual size */ .long _end_header - efi_start /* Virtual address */ .long _edata - _end_header /* Size of raw data */ .long _end_header - efi_start /* Pointer to raw data */ .long 0 /* Pointer to relocations */ .long 0 /* Pointer to line numbers */ .short 0 /* Number of relocations */ .short 0 /* Number of line numbers */ .long (IMAGE_SCN_CNT_CODE | IMAGE_SCN_MEM_EXECUTE | \ IMAGE_SCN_MEM_READ) /* Characteristics */ _end_header: .text _start: /* Save the boot params to the stack */ push {r0, r1} adr r0, .Lbase ldr r1, [r0] sub r5, r0, r1 ldr r0, .Limagebase add r0, r0, r5 ldr r1, .Ldynamic add r1, r1, r5 bl self_reloc /* Zero the BSS, _reloc fixed the values for us */ ldr r0, .Lbss ldr r1, .Lbssend mov r2, #0 1: cmp r0, r1 bge 2f str r2, [r0], #4 b 1b 2: pop {r0, r1} bl efi_main 1: b 1b .Lbase: .word . .Limagebase: .word ImageBase .Ldynamic: .word _DYNAMIC .Lbss: .word __bss_start .Lbssend: .word __bss_end .align 3 stack: .space 512 stack_end:
