57 lines
1.5 KiB
ArmAsm
57 lines
1.5 KiB
ArmAsm
/* Initial boot
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*
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* Copyright (c) 2006 CodeSourcery Inc
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*
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* The authors hereby grant permission to use, copy, modify, distribute,
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* and license this software and its documentation for any purpose, provided
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* that existing copyright notices are retained in all copies and that this
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* notice is included verbatim in any distributions. No written agreement,
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* license, or royalty fee is required for any of the authorized uses.
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* Modifications to this software may be copyrighted by their authors
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* and need not follow the licensing terms described here, provided that
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* the new terms are clearly indicated on the first page of each file where
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* they apply.
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*/
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#include "asm.h"
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.text
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.extern __stack
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.extern __heap_end
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.weak __heap_end
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.extern __start1
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/* __reset should cause a HALT in a hosted executable and
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fall into __start for an unhosted executable. The user is
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free to override this with their own declaration. */
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.globl __reset
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.weak __reset
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__reset:
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#if HOSTED
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HALT
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#endif
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.globl __start
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__start:
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/* Initialize stack */
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move.l IMM(__stack), sp
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move.l IMM(0), fp
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move.l IMM(__heap_end), d1
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#if HOSTED
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/* INIT_SIM syscall. Allows changing sp & d1. */
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move.l IMM(1),d0
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/* The semihosting sequence is 'nop; halt;sentinel' aligned to
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a 4 byte boundary. The sentinel is an ill formed instruction
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(movec %sp,0). The debugger will adjust the pc, so it is never
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executed. */
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.balignw 4,0x4e71
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nop
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halt
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.long 0x4e7bf000
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#endif
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move.l d1,sp@-
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move.l fp,sp@- /* Dummy return address */
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jmp __start1
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