1/* crt0-efi-x86_64.S - x86_64 EFI startup code. 2 Copyright (C) 1999 Hewlett-Packard Co. 3 Contributed by David Mosberger <davidm@hpl.hp.com>. 4 Copyright (C) 2005 Intel Co. 5 Contributed by Fenghua Yu <fenghua.yu@intel.com>. 6 7 All rights reserved. 8 9 Redistribution and use in source and binary forms, with or without 10 modification, are permitted provided that the following conditions 11 are met: 12 13 * Redistributions of source code must retain the above copyright 14 notice, this list of conditions and the following disclaimer. 15 * Redistributions in binary form must reproduce the above 16 copyright notice, this list of conditions and the following 17 disclaimer in the documentation and/or other materials 18 provided with the distribution. 19 * Neither the name of Hewlett-Packard Co. nor the names of its 20 contributors may be used to endorse or promote products derived 21 from this software without specific prior written permission. 22 23 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND 24 CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, 25 INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 26 MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 27 DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS 28 BE LIABLE FOR ANYDIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 29 OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 30 PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 31 PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 32 THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR 33 TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF 34 THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 35 SUCH DAMAGE. 36*/ 37 .text 38 .align 4 39 40 .globl _start 41 .type _start,%function 42_start: 43 subq $8, %rsp 44 pushq %rcx 45 pushq %rdx 46 470: 48 lea ImageBase(%rip), %rdi 49 lea _DYNAMIC(%rip), %rsi 50 51 popq %rcx 52 popq %rdx 53 pushq %rcx 54 pushq %rdx 55 call _relocate 56 57 popq %rdi 58 popq %rsi 59 60 call _entry 61 addq $8, %rsp 62 63.exit: 64 ret 65 66 // hand-craft a dummy .reloc section so EFI knows it's a relocatable executable: 67 68 .data 69dummy: .4byte 0 70 71#define IMAGE_REL_ABSOLUTE 0 72 .section .reloc, "a" 73label1: 74 .4byte dummy-label1 // Page RVA 75 .4byte 12 // Block Size (2*4+2*2), must be aligned by 32 Bits 76 .2byte (IMAGE_REL_ABSOLUTE<<12) + 0 // reloc for dummy 77 .2byte (IMAGE_REL_ABSOLUTE<<12) + 0 // reloc for dummy 78 79#if defined(__ELF__) && defined(__linux__) 80 .section .note.GNU-stack,"",%progbits 81#endif 82