1/* crt0-efi-ia32.S - x86 EFI startup code. 2 Copyright (C) 1999 Hewlett-Packard Co. 3 Contributed by David Mosberger <davidm@hpl.hp.com>. 4 5 All rights reserved. 6 7 Redistribution and use in source and binary forms, with or without 8 modification, are permitted provided that the following conditions 9 are met: 10 11 * Redistributions of source code must retain the above copyright 12 notice, this list of conditions and the following disclaimer. 13 * Redistributions in binary form must reproduce the above 14 copyright notice, this list of conditions and the following 15 disclaimer in the documentation and/or other materials 16 provided with the distribution. 17 * Neither the name of Hewlett-Packard Co. nor the names of its 18 contributors may be used to endorse or promote products derived 19 from this software without specific prior written permission. 20 21 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND 22 CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, 23 INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 24 MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 25 DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS 26 BE LIABLE FOR ANYDIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 27 OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 28 PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 29 PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 30 THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR 31 TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF 32 THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 SUCH DAMAGE. 34*/ 35 36 .text 37 .align 4 38 39 .globl _start 40_start: 41 pushl %ebp 42 movl %esp,%ebp 43 44 pushl 12(%ebp) # copy "image" argument 45 pushl 8(%ebp) # copy "systab" argument 46 47 call 0f 480: popl %eax 49 movl %eax,%ebx 50 51 addl $ImageBase-0b,%eax # %eax = ldbase 52 addl $_DYNAMIC-0b,%ebx # %ebx = _DYNAMIC 53 54 pushl %ebx # pass _DYNAMIC as second argument 55 pushl %eax # pass ldbase as first argument 56 call _relocate 57 popl %ebx 58 popl %ebx 59 testl %eax,%eax 60 jne .exit 61 62 call _entry # call app with "image" and "systab" argument 63 64.exit: leave 65 ret 66 67 // hand-craft a dummy .reloc section so EFI knows it's a relocatable executable: 68 69 .data 70dummy: .long 0 71 72#define IMAGE_REL_ABSOLUTE 0 73 .section .reloc 74 .long dummy // Page RVA 75 .long 12 // Block Size (2*4+2*2), must be aligned by 32 Bits 76 .word (IMAGE_REL_ABSOLUTE<<12) + 0 // reloc for dummy 77 .word (IMAGE_REL_ABSOLUTE<<12) + 0 // reloc for dummy 78 79#if defined(__ELF__) && defined(__linux__) 80 .section .note.GNU-stack,"",%progbits 81#endif 82