Change-Id: Ia9170bd3d04e76dbf9321ca7ea4be23b5e468d21 Signed-off-by: Stefan Reinauer <reinauer@google.com> Reviewed-on: http://review.coreboot.org/2033 Tested-by: build bot (Jenkins) Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
		
			
				
	
	
		
			105 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
			
		
		
	
	
			105 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
| /*
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|  * This file is part of the libpayload project.
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|  *
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|  * Copyright (C) 2008 Advanced Micro Devices, Inc.
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|  *
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|  * Redistribution and use in source and binary forms, with or without
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|  * modification, are permitted provided that the following conditions
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|  * are met:
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|  * 1. Redistributions of source code must retain the above copyright
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|  *    notice, this list of conditions and the following disclaimer.
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|  * 2. Redistributions in binary form must reproduce the above copyright
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|  *    notice, this list of conditions and the following disclaimer in the
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|  *    documentation and/or other materials provided with the distribution.
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|  * 3. The name of the author may not be used to endorse or promote products
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|  *    derived from this software without specific prior written permission.
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|  *
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|  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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|  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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|  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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|  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
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|  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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|  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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|  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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|  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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|  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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|  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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|  * SUCH DAMAGE.
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|  */
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| 
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| 	.code32
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| 	.global _entry, _leave
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| 	.text
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| 	.align 4
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| 
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| /*
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|  * Our entry point - assume that the CPU is in 32 bit protected mode and
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|  * all segments are in a flat model. That's our operating mode, so we won't
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|  * change anything.
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|  */
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| _entry:
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| 	jmp _init
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| 
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| 	.align 4
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| 
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| #define MB_MAGIC 0x1BADB002
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| #define MB_FLAGS 0x00010003
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| 
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| mb_header:
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| 	.long MB_MAGIC
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| 	.long MB_FLAGS
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| 	.long -(MB_MAGIC + MB_FLAGS)
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| 	.long mb_header
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| 	.long _start
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| 	.long _edata
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| 	.long _end
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| 	.long _init
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| 
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| /*
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|  * This function saves off the previous stack and switches us to our
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|  * own execution environment.
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|  */
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| _init:
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| 	/* No interrupts, please. */
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| 	cli
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| 
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| 	/* There is a bunch of stuff missing here to take arguments on the stack
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| 	 * See http://www.coreboot.org/Payload_API and exec.S.
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| 	 */
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| 	/* Store current stack pointer. */
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| 	movl %esp, %esi
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| 
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| 	/* Store EAX and EBX */
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| 	movl %eax,loader_eax
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| 	movl %ebx,loader_ebx
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| 
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| 	/* Clear the bss */
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| 	cld
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| 	movl $.bss, %edi
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| 	movl $_end, %ecx
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| 	subl %edi, %ecx
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| 	xor %ax, %ax
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| 	rep stosb
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| 
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| 	/* Setup new stack. */
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| 	movl $_stack, %ebx
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| 
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| 	movl %ebx, %esp
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| 
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| 	/* Save old stack pointer. */
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| 	pushl %esi
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| 
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| 	/* Let's rock. */
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| 	call start_main
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| 
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| 	/* %eax has the return value - pass it on unmolested */
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| _leave:
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| 	/* Get old stack pointer. */
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| 	popl %ebx
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| 
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| 	/* Restore old stack. */
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| 	movl %ebx, %esp
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| 
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| 	/* Return to the original context. */
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| 	ret
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