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      1 /*	$NetBSD: crt0-efi-x86_64.S,v 1.1.1.2 2021/09/30 18:50:09 jmcneill Exp $	*/
      2 
      3 /* crt0-efi-x86_64.S - x86_64 EFI startup code.
      4    Copyright (C) 1999 Hewlett-Packard Co.
      5 	Contributed by David Mosberger <davidm (at) hpl.hp.com>.
      6    Copyright (C) 2005 Intel Co.
      7 	Contributed by Fenghua Yu <fenghua.yu (at) intel.com>.
      8 
      9     All rights reserved.
     10 
     11     Redistribution and use in source and binary forms, with or without
     12     modification, are permitted provided that the following conditions
     13     are met:
     14 
     15     * Redistributions of source code must retain the above copyright
     16       notice, this list of conditions and the following disclaimer.
     17     * Redistributions in binary form must reproduce the above
     18       copyright notice, this list of conditions and the following
     19       disclaimer in the documentation and/or other materials
     20       provided with the distribution.
     21     * Neither the name of Hewlett-Packard Co. nor the names of its
     22       contributors may be used to endorse or promote products derived
     23       from this software without specific prior written permission.
     24 
     25     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
     26     CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
     27     INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
     28     MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
     29     DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS
     30     BE LIABLE FOR ANYDIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
     31     OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
     32     PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
     33     PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     34     THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
     35     TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
     36     THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     37     SUCH DAMAGE.
     38 */
     39 	.text
     40 	.align 4
     41 
     42 	.globl _start
     43 _start:
     44 	subq $8, %rsp
     45 	pushq %rcx
     46 	pushq %rdx
     47 
     48 0:
     49 	lea ImageBase(%rip), %rdi
     50 	lea _DYNAMIC(%rip), %rsi
     51 
     52 	popq %rcx
     53 	popq %rdx
     54 	pushq %rcx
     55 	pushq %rdx
     56 	call _relocate
     57 
     58 	popq %rdi
     59 	popq %rsi
     60 
     61 	call efi_main
     62 	addq $8, %rsp
     63 
     64 .exit:
     65   	ret
     66 
     67  	// hand-craft a dummy .reloc section so EFI knows it's a relocatable executable:
     68 
     69  	.data
     70 dummy:	.long	0
     71 
     72 #define IMAGE_REL_ABSOLUTE	0
     73  	.section .reloc, "a"
     74 label1:
     75 	.long	dummy-label1				// Page RVA
     76 	.long	12					// Block Size (2*4+2*2), must be aligned by 32 Bits
     77 	.word	(IMAGE_REL_ABSOLUTE<<12) +  0		// reloc for dummy
     78 	.word	(IMAGE_REL_ABSOLUTE<<12) +  0		// reloc for dummy
     79 
     80