43 lines
604 B
ArmAsm
43 lines
604 B
ArmAsm
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# entry.S
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.option norvc
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.section .data
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.section .text.init
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.global _entry
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_entry:
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# Any hardware threads (hart) that are not bootstrapping
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# need to wait for an IPI
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csrr t0, mhartid
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bnez t0, 3f
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# SATP should be zero, but let's make sure
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csrw satp, zero
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.option push
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.option norelax
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la gp, _global_pointer
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.option pop
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li t5, 0xffff
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csrw medeleg, t5
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csrw mideleg, t5
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la sp, _stack_end
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li t0, (0b11 << 11) | (1 << 7) | (1 << 3)
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csrw mstatus, t0
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la t0, _bss_start
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la t1, _bss_end
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bgeu t0, t1, 2f
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1:
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sb zero, 0(t0)
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addi t0, t0, 1
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bne t0, t1, 1b
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2:
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j 4f
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3:
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wfi
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j 3b
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4:
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tail start
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