27 lines
695 B
ArmAsm
27 lines
695 B
ArmAsm
# qemu -kernel starts at 0x1000. the instructions
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# there seem to be provided by qemu, as if it
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# were a ROM. the code at 0x1000 jumps to
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# 0x80000000, the _start function here,
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# in machine mode. each CPU starts here.
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.section .data
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.globl stack0
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.section .text
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.globl start
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.section .text
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.globl _entry
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_entry:
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# set up a stack for C.
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# stack0 is declared in start.c,
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# with a 4096-byte stack per CPU.
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# sp = stack0 + (hartid * 4096)
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la sp, stack0
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li a0, 1024*4
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csrr a1, mhartid
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addi a1, a1, 1
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mul a0, a0, a1
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add sp, sp, a0
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# jump to start() in start.c
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call start
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junk:
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j junk
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