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			136 lines
		
	
	
		
			2.9 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
			
		
		
	
	
			136 lines
		
	
	
		
			2.9 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
| /*
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|  *  U-boot - i386 Startup Code
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|  *
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|  *  Copyright (c) 2002	Omicron Ceti AB, Daniel Engström <denaiel@omicron.se>
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|  *
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|  * See file CREDITS for list of people who contributed to this
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|  * project.
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|  *
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|  * This program is free software; you can redistribute it and/or
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|  * modify it under the terms of the GNU General Public License as
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|  * published by the Free Software Foundation; either version 2 of
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|  * the License, or (at your option) any later version.
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|  *
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|  * This program is distributed in the hope that it will be useful,
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|  * but WITHOUT ANY WARRANTY; without even the implied warranty of
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|  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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|  * GNU General Public License for more details.
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|  *
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|  * You should have received a copy of the GNU General Public License
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|  * along with this program; if not, write to the Free Software
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|  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
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|  * MA 02111-1307 USA
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|  */
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| 
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| 
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| #include <config.h>
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| #include <version.h>
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| 
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| 
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| .section .text
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| .code32
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| .globl _start
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| .type _start, @function
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| .globl _i386boot_start
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| _i386boot_start:
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| _start:
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| 	movl    $0x18,%eax	/* Load our segement registes, the
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| 				 * gdt have already been loaded by start16.S */
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| 	movw    %ax,%fs
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| 	movw	%ax,%ds
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| 	movw    %ax,%gs
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| 	movw    %ax,%es
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| 	movw    %ax,%ss
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| 
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| 	/* We call a few functions in the board support package
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| 	 * since we have no stack yet we'll have to use %ebp
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| 	 * to store the return address */
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| 
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| 	/* Early platform init (setup gpio, etc ) */
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| 	mov     $early_board_init_ret, %ebp
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| 	jmp	early_board_init
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| early_board_init_ret:
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| 
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| 	/* The __port80 entry-point should be usabe by now */
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| 	/* so we try to indicate progress */
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| 	movw	$0x01, %ax
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| 	movl	$.progress0, %ebp
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| 	jmp	show_boot_progress_asm
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| .progress0:
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| 
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| 	/* size memory */
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| 	mov	$mem_init_ret, %ebp
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| 	jmp     mem_init
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| mem_init_ret:
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| 
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| 	/* Check we have enough memory for stack */
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| 	movl	$CONFIG_SYS_STACK_SIZE, %ecx
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| 	cmpl	%ecx, %eax
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| 	jae	mem_ok
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| 
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| 	/* indicate (lack of) progress */
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| 	movw	$0x81, %ax
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| 	movl	$.progress0a, %ebp
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| 	jmp	show_boot_progress_asm
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| .progress0a:
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| 	jmp	die
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| mem_ok:
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| 	/* Set stack pointer to upper memory limit*/
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| 	movl    %eax, %esp
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| 
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| 	/* indicate progress */
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| 	movw	$0x02, %ax
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| 	movl	$.progress1, %ebp
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| 	jmp	show_boot_progress_asm
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| .progress1:
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| 
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| 	/* Test the stack */
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| 	pushl	$0
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| 	popl	%eax
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| 	cmpl	$0, %eax
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| 	jne	no_stack
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| 	push	$0x55aa55aa
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| 	popl	%ebx
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| 	cmpl	$0x55aa55aa, %ebx
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| 	je	stack_ok
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| 
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| no_stack:
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| 	/* indicate (lack of) progress */
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| 	movw	$0x82, %ax
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| 	movl	$.progress1a, %ebp
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| 	jmp	show_boot_progress_asm
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| .progress1a:
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| 	jmp die
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| 
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| 
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| stack_ok:
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| 	/* indicate progress */
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| 	movw	$0x03, %ax
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| 	movl	$.progress2, %ebp
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| 	jmp	show_boot_progress_asm
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| .progress2:
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| 
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| 	wbinvd
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| 
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| 	/* Get upper memory limit */
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| 	movl %esp, %ecx
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| 	subl $CONFIG_SYS_STACK_SIZE, %ecx
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| 
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| 	/* Create a Stack Frame */
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| 	pushl %ebp
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| 	movl %esp, %ebp
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| 
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| 	/* stack_limit parameter */
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| 	pushl	%ecx
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| 	call	board_init_f	/* Enter, U-boot! */
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| 
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| 	/* indicate (lack of) progress */
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| 	movw	$0x85, %ax
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| 	movl	$.progress4a, %ebp
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| 	jmp	show_boot_progress_asm
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| .progress4a:
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| 
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| die:	hlt
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| 	jmp	die
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| 	hlt
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