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/********************************************************************************************
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* File: start.S - Startup Code for ARM920 CPU-core
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* Version: 1.0.0
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* Copyright: 2011 (c) Guo Wenxue <guowenxue@gmail.com>
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* Description: When system power up, the CPU will comes here to excute the first code here.
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* ChangeLog: 1, Release initial version on "Tue Jul 12 16:43:18 CST 2011"
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*
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*******************************************************************************************/
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/*
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*************************************************************************
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*
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* Jump vector table as in table 3.1 in [1]
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*
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*************************************************************************
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*/
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.globl _start
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_start: b start_code
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_TEXT_BASE:
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.word TEXT_BASE
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.globl _armboot_start
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_armboot_start:
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.word _start
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/*
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* These are defined in the board-specific linker script.
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*/
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.globl _bss_start
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_bss_start:
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.word __bss_start
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.globl _bss_end
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_bss_end:
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.word _end
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start_code:
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/* Set up the stack */
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stack_setup:
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ldr r0, =TEXT_BASE /* upper 128 KiB: relocated uboot */
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sub r0, r0, #CONFIG_SYS_MALLOC_LEN /* malloc area */
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sub sp, r0, #12 /* leave 3 words for abort-stack */
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bic sp, sp, #7 /* 8-byte alignment for ABI compliance */
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clear_bss:
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ldr r0, _bss_start /* find start of bss segment */
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ldr r1, _bss_end /* stop here */
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mov r2, #0x00000000 /* clear */
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clbss_l:str r2, [r0] /* clear loop... */
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add r0, r0, #4
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cmp r0, r1
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ble clbss_l
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bl bootstrap_main
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