25 lines
694 B
ArmAsm
25 lines
694 B
ArmAsm
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// TODO: CHECK/REPLACE/UPDATE OLD CODE (this file is based on xv6)
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// qemu -kernel loads the kernel at 0x80000000
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// and causes each hart (i.e. CPU) to jump there.
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// kernel.ld causes the following code to
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// be placed at 0x80000000.
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.option norvc
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.section .text
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.global _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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spin:
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j spin
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