44 lines
881 B
ArmAsm
44 lines
881 B
ArmAsm
.equ IO_BASE, 0x400000
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.text
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.global _start
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.type _start, @function
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_start:
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.option push
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.option norelax
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li gp,IO_BASE
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.option pop
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li sp,0x1800
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# zero-init bss section:
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# clears from _sbss to _ebss
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# _sbss and _ebss are defined by linker script (spiflash.ld)
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la a0, _sbss
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la a1, _ebss
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bge a0, a1, end_init_bss
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loop_init_bss:
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sw zero, 0(a0)
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addi a0, a0, 4
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blt a0, a1, loop_init_bss
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end_init_bss:
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# copy data section from SPI Flash to BRAM:
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# copies from _sidata (in flash) to _sdata ... _edata (in BRAM)
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# _sidata, _sdata and _edata are defined by linker script (spiflash.ld)
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la a0, _sidata
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la a1, _sdata
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la a2, _edata
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bge a1, a2, end_init_data
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loop_init_data:
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lw a3, 0(a0)
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sw a3, 0(a1)
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addi a0, a0, 4
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addi a1, a1, 4
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blt a1, a2, loop_init_data
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end_init_data:
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call main
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ebreak
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