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/*
* File : context_gcc.S
* This file is part of RT-Thread RTOS
* COPYRIGHT (C) 2018, RT-Thread Development Team
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Change Logs:
* Date Author Notes
* 2018-05-29 tanek first implementation
*/
.section .text.entry
.align 2
.global trap_entry
trap_entry:
// save all from thread context
addi sp, sp, -32 * 4
sw x1, 1 * 4(sp)
li t0, 0x80
sw t0, 2 * 4(sp)
sw x4, 4 * 4(sp)
sw x5, 5 * 4(sp)
sw x6, 6 * 4(sp)
sw x7, 7 * 4(sp)
sw x8, 8 * 4(sp)
sw x9, 9 * 4(sp)
sw x10, 10 * 4(sp)
sw x11, 11 * 4(sp)
sw x12, 12 * 4(sp)
sw x13, 13 * 4(sp)
sw x14, 14 * 4(sp)
sw x15, 15 * 4(sp)
sw x16, 16 * 4(sp)
sw x17, 17 * 4(sp)
sw x18, 18 * 4(sp)
sw x19, 19 * 4(sp)
sw x20, 20 * 4(sp)
sw x21, 21 * 4(sp)
sw x22, 22 * 4(sp)
sw x23, 23 * 4(sp)
sw x24, 24 * 4(sp)
sw x25, 25 * 4(sp)
sw x26, 26 * 4(sp)
sw x27, 27 * 4(sp)
sw x28, 28 * 4(sp)
sw x29, 29 * 4(sp)
sw x30, 30 * 4(sp)
sw x31, 31 * 4(sp)
// switch to interrupt stack
move s0, sp
la sp, _sp
// interrupt handle
call rt_interrupt_enter
csrr a0, mcause
csrr a1, mepc
mv a2, sp
call handle_trap
call rt_interrupt_leave
// switch to from thread stack
move sp, s0
// need to switch new thread
la s0, rt_thread_switch_interrupt_flag
lw s2, 0(s0)
beqz s2, spurious_interrupt
sw zero, 0(s0)
csrr a0, mepc
sw a0, 0 * 4(sp)
la s0, rt_interrupt_from_thread
lw s1, 0(s0)
sw sp, 0(s1)
la s0, rt_interrupt_to_thread
lw s1, 0(s0)
lw sp, 0(s1)
lw a0, 0 * 4(sp)
csrw mepc, a0
spurious_interrupt:
lw x1, 1 * 4(sp)
// Remain in M-mode after mret
li t0, 0x00001800
csrs mstatus, t0
lw t0, 2 * 4(sp)
csrs mstatus, t0
lw x4, 4 * 4(sp)
lw x5, 5 * 4(sp)
lw x6, 6 * 4(sp)
lw x7, 7 * 4(sp)
lw x8, 8 * 4(sp)
lw x9, 9 * 4(sp)
lw x10, 10 * 4(sp)
lw x11, 11 * 4(sp)
lw x12, 12 * 4(sp)
lw x13, 13 * 4(sp)
lw x14, 14 * 4(sp)
lw x15, 15 * 4(sp)
lw x16, 16 * 4(sp)
lw x17, 17 * 4(sp)
lw x18, 18 * 4(sp)
lw x19, 19 * 4(sp)
lw x20, 20 * 4(sp)
lw x21, 21 * 4(sp)
lw x22, 22 * 4(sp)
lw x23, 23 * 4(sp)
lw x24, 24 * 4(sp)
lw x25, 25 * 4(sp)
lw x26, 26 * 4(sp)
lw x27, 27 * 4(sp)
lw x28, 28 * 4(sp)
lw x29, 29 * 4(sp)
lw x30, 30 * 4(sp)
lw x31, 31 * 4(sp)
addi sp, sp, 32 * 4
mret
.weak handle_trap
handle_trap:
1:
j 1b
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