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      1 /* crt0-efi-ia32.S - x86 EFI startup code.
      2    Copyright (C) 1999 Hewlett-Packard Co.
      3 	Contributed by David Mosberger <davidm (at) 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
     48 0:	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 efi_main			# 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
     70 dummy:	.long	0
     71 
     72 #define IMAGE_REL_ABSOLUTE	0
     73  	.section .reloc
     74  	.long	dummy					// Page RVA
     75  	.long	10					// Block Size (2*4+2)
     76  	.word	(IMAGE_REL_ABSOLUTE<<12) +  0		// reloc for dummy
     77