93 lines
1.7 KiB
ArmAsm
93 lines
1.7 KiB
ArmAsm
|
/*
|
||
|
|
* Copyright (c) 2021-2023 HPMicro
|
||
|
|
*
|
||
|
|
* SPDX-License-Identifier: BSD-3-Clause
|
||
|
|
*
|
||
|
|
*/
|
||
|
|
#include <rtconfig.h>
|
||
|
|
#include "hpm_csr_regs.h"
|
||
|
|
.section .start, "ax"
|
||
|
|
|
||
|
|
.global _start
|
||
|
|
.type _start,@function
|
||
|
|
|
||
|
|
_start:
|
||
|
|
/* Initialize global pointer */
|
||
|
|
.option push
|
||
|
|
.option norelax
|
||
|
|
la gp, __global_pointer$
|
||
|
|
la tp, __thread_pointer
|
||
|
|
.option pop
|
||
|
|
|
||
|
|
#ifdef __riscv_flen
|
||
|
|
/* Enable FPU */
|
||
|
|
li t0, CSR_MSTATUS_FS_MASK
|
||
|
|
csrrs t0, mstatus, t0
|
||
|
|
|
||
|
|
/* Initialize FCSR */
|
||
|
|
fscsr zero
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#ifdef INIT_EXT_RAM_FOR_DATA
|
||
|
|
la t0, _stack_in_dlm
|
||
|
|
mv sp, t0
|
||
|
|
call _init_ext_ram
|
||
|
|
#endif
|
||
|
|
|
||
|
|
/* Initialize stack pointer */
|
||
|
|
la t0, _stack
|
||
|
|
mv sp, t0
|
||
|
|
|
||
|
|
#ifdef __nds_execit
|
||
|
|
/* Initialize EXEC.IT table */
|
||
|
|
la t0, _ITB_BASE_
|
||
|
|
csrw uitb, t0
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#ifdef __riscv_flen
|
||
|
|
/* Enable FPU */
|
||
|
|
li t0, CSR_MSTATUS_FS_MASK
|
||
|
|
csrrs t0, mstatus, t0
|
||
|
|
|
||
|
|
/* Initialize FCSR */
|
||
|
|
fscsr zero
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#ifdef HPM_USING_VECTOR_PREEMPTED_MODE
|
||
|
|
/* Initial machine trap-vector Base */
|
||
|
|
la t0, __vector_table
|
||
|
|
csrw mtvec, t0
|
||
|
|
/* Enable vectored external PLIC interrupt */
|
||
|
|
csrsi CSR_MMISC_CTL, 2
|
||
|
|
#else
|
||
|
|
/* Initial machine trap-vector Base */
|
||
|
|
la t0, SW_handler
|
||
|
|
csrw mtvec, t0
|
||
|
|
/* Disable vectored external PLIC interrupt */
|
||
|
|
csrci CSR_MMISC_CTL, 2
|
||
|
|
#endif
|
||
|
|
|
||
|
|
/* System reset handler */
|
||
|
|
call reset_handler
|
||
|
|
|
||
|
|
/* Infinite loop, if returned accidently */
|
||
|
|
1: j 1b
|
||
|
|
|
||
|
|
.weak nmi_handler
|
||
|
|
nmi_handler:
|
||
|
|
1: j 1b
|
||
|
|
|
||
|
|
.global default_irq_handler
|
||
|
|
.weak default_irq_handler
|
||
|
|
.align 2
|
||
|
|
default_irq_handler:
|
||
|
|
1: j 1b
|
||
|
|
|
||
|
|
.macro IRQ_HANDLER irq
|
||
|
|
.weak default_isr_\irq
|
||
|
|
.set default_isr_\irq, default_irq_handler
|
||
|
|
.long default_isr_\irq
|
||
|
|
.endm
|
||
|
|
|
||
|
|
#include "vectors.S"
|