27 lines
756 B
ArmAsm
27 lines
756 B
ArmAsm
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# C runtime, modified from
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# https://twilco.github.io/riscv-from-scratch/2019/04/27/riscv-from-scratch-2.html#stop--hammertime-runtime
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# in the init section which is "allocatable" and "executable"
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.section .init, "ax"
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# entry point for the kernel
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.global _start
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_start:
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.cfi_startproc
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.cfi_undefined ra
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# initialize the global pointer register
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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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# initialize the stack pointer and frame pointer registers
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# FIXME: when putting the stack at the end of RAM with system memory >2G
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# it fails to link with the error: relocation truncated to fit:
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# R_RISCV_HI20 against '__stack_top'
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la sp, __stack_top
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add s0, sp, zero
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# jump to main
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jal zero, main
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.cfi_endproc
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.end
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