39 lines
672 B
ArmAsm
39 lines
672 B
ArmAsm
.globl _start
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#
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# NOTE: Registers r10-r11 are reserved for the interrupt handler
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# while the others can be used by the main loop/start code.
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_start:
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# patch the DBT handler
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add r1, r0, handler
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ldw r2, @(r1, 0)
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ldw r3, @(r1, 4)
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# DBT vector address
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add r1, r0, 0xfffff120
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stw r2, @(r1, 0)
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stw r3, @(r1, 4)
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# try out the breakpoint/return
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add r2, r0, 47
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#dbt
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nop
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.long 0x00b00000
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nop
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# exit with what ever the breakpoint hander set r2 to.
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nop
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.long 0x0e000004
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nop
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handler:
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jmp real_handler
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# The Breakpoint handler sets r2 to 0 if PSW was set correctly.
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real_handler:
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mvfsys r2, cr0
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sub r2, r0, 0x08000000
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#rtd
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nop
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.long 0x00a00000
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nop
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