2026-02-08 21:23:47 +00:00
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.section .text
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.global _start
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_start:
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la sp, stack_top # Set up the stack pointer
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la t0, trap_entry # Set up the trap handler
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csrw mtvec, t0 # Set the trap vector to our trap handler
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2026-02-09 02:55:15 +00:00
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li t0, 0x00006000 # Load the mask for FS bits. enable float
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csrs mstatus, t0 # Set the FS bits to 11 (Dirty/Initial). enable float
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call kmain # Jump to our C code
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loop:
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wfi # Wait for Interrupt (saves CPU)
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j loop # Infinite loop if C returns
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.align 4
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trap_entry:
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csrr a0, mcause # Argument 1: mcause
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csrr a1, mepc # Argument 2: mepc
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j handle_trap
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.section .bss
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.align 16
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stack_low:
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.skip 4096 # 4KB of stack space
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stack_top:
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