2025-04-13 17:29:34 +08:00
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.syntax unified
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.cpu cortex-m0plus
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.thumb
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.global boot2_pre
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.section .text.boot2_pre
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.type boot2_pre, %function
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boot2_pre:
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2025-04-21 21:34:34 +08:00
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cpsid i
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/* clear bss section */
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ldr r0, =0
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ldr r1, =_bss_start
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ldr r2, =_bss_end
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cmp r1, r2
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bhs 2f
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1:
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str r0, [r1]
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adds r1, r1, #4
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cmp r1, r2
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blo 1b
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2:
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2025-04-13 21:33:56 +08:00
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ldr r0, =_stack_top
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msr msp, r0
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bl boot2_copy_self
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bl main
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2025-04-19 21:07:29 +08:00
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b .
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2025-04-13 17:29:34 +08:00
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.size .boot2_pre, .-boot2_pre
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