63 lines
875 B
ArmAsm
63 lines
875 B
ArmAsm
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// See LICENSE for license details.
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#include "encoding.h"
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.section .init
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.globl _start_1
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.type _start_1,@function
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_start_1:
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li t0, MSTATUS_MIE
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csrc mstatus, t0
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li t0, MIP_MTIP
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csrc mie, t0
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li t0, MIP_MEIP
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csrc mie, t0
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li t0, 0
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csrc mcause, t0
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la gp, _gp
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la sp, _sp
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/* Load data section */
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la a0, _data_lma
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la a1, _data
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la a2, _edata
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bgeu a1, a2, 2f
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1:
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lw t0, (a0)
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sw t0, (a1)
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addi a0, a0, 4
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addi a1, a1, 4
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bltu a1, a2, 1b
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2:
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/* Clear bss section */
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la a0, __bss_start
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la a1, _end
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bgeu a0, a1, 2f
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1:
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sw zero, (a0)
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addi a0, a0, 4
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bltu a0, a1, 1b
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2:
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/* init function*/
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call _init_1
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#ifndef __riscv_float_abi_soft
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/* Enable FPU */
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li t0, MSTATUS_FS
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csrs mstatus, t0
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csrr t1, mstatus
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and t1, t1, t0
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beqz t1, 1f
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fssr x0
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1:
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#endif
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/* argc = argv = 0 */
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li a0, 0
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li a1, 0
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call main
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# tail exit
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1: j 1b
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