rt-thread/bsp/bluetrum/libcpu/cpu/context_gcc.S

227 lines
6.0 KiB
ArmAsm

/*
* Copyright (c) 2020-2020, Bluetrum Development Team
*
* SPDX-License-Identifier: Apache-2.0
*
* Change Logs:
* Date Author Notes
* 2020/11/18 greedyhao The first version.
*/
#include "ab32vg1.h"
.global rt_interrupt_from_thread
.global rt_interrupt_to_thread
.global rt_cur_thread_sp
.global rt_thread_switch_interrupt_flag
.global rt_interrupt_nest
/*
* rt_base_t rt_hw_interrupt_disable();
* a0 -> return
*/
.global rt_hw_interrupt_disable
rt_hw_interrupt_disable:
lw a5, PICCON(zero)
mv a0, a5
andi a5, a5, -2
sw a5, PICCON(zero)
ret
/*
* void rt_hw_interrupt_enable(rt_base_t level);
* a0 -> level
*/
.global rt_hw_interrupt_enable
rt_hw_interrupt_enable:
andi a0, a0, 1
beqz a0,enable_int_ret
lw a5, PICCON(zero)
ori a5, a5, 1
sw a5,PICCON(zero)
enable_int_ret:
ret
/* Macro for saving task context */
.macro save_context
addi sp, sp, -124
/* Save Context */
sw x1, 0(sp)
sw x4, 4(sp)
sw x5, 8(sp)
sw x6, 12(sp)
sw x7, 16(sp)
sw x8, 20(sp)
sw x9, 24(sp)
sw x10, 28(sp)
sw x11, 32(sp)
sw x12, 36(sp)
sw x13, 40(sp)
sw x14, 44(sp)
sw x15, 48(sp)
sw x16, 52(sp)
sw x17, 56(sp)
sw x18, 60(sp)
sw x19, 64(sp)
sw x20, 68(sp)
sw x21, 72(sp)
sw x22, 76(sp)
sw x23, 80(sp)
sw x24, 84(sp)
sw x25, 88(sp)
sw x26, 92(sp)
sw x27, 96(sp)
sw x28, 100(sp)
sw x29, 104(sp)
sw x30, 108(sp)
sw x31, 112(sp)
lw a5, EPC(zero) //Saves current program counter (EPC) as task program counter
sw a5, 116(sp)
lw a5, EPICCON(zero)
sw a5, 120(sp)
sw sp, rt_cur_thread_sp, a4 //store sp in preempted tasks tcb
.endm
/* Macro for restoring task context */
.macro restore_context
la a5, rt_cur_thread_sp
lw sp, 0(a5) //get new task stack pointer
/* Load task program counter EPC*/
lw a5, 116(sp)
sw a5, EPC(zero)
lw a5, 120(sp)
sw a5, EPICCON(zero)
/* Restore registers,
Skip global pointer because that does not change */
lw x1, 0(sp)
lw x4, 4(sp)
lw x5, 8(sp)
lw x6, 12(sp)
lw x7, 16(sp)
lw x8, 20(sp)
lw x9, 24(sp)
lw x10, 28(sp)
lw x11, 32(sp)
lw x12, 36(sp)
lw x13, 40(sp)
lw x14, 44(sp)
lw x15, 48(sp)
lw x16, 52(sp)
lw x17, 56(sp)
lw x18, 60(sp)
lw x19, 64(sp)
lw x20, 68(sp)
lw x21, 72(sp)
lw x22, 76(sp)
lw x23, 80(sp)
lw x24, 84(sp)
lw x25, 88(sp)
lw x26, 92(sp)
lw x27, 96(sp)
lw x28, 100(sp)
lw x29, 104(sp)
lw x30, 108(sp)
lw x31, 112(sp)
addi sp, sp, 124
mret
.endm
/*
* void rt_hw_context_switch_to(rt_uint32 to);
* r0 --> to
*/
.globl rt_hw_context_switch_to
rt_hw_context_switch_to:
sw zero, rt_interrupt_from_thread, a4 /*set from thread to 0*/
sw a0, rt_interrupt_to_thread, a4 /*set rt_interrupt_to_thread*/
sb zero, rt_interrupt_nest, a4 /*rt_interrupt_nest = 0*/
li a5, 1
sw a5, rt_thread_switch_interrupt_flag, a4 // rt_thread_switch_interrupt_flag = 1;
SWINT /*kick soft interrupt*/
lw a5, PICCON(zero) /*enable interrupt*/
ori a5, a5, 1
sw a5, PICCON(zero)
ret
/*
* void rt_hw_context_switch(rt_uint32 from, rt_uint32 to);
* a0 --> from
* a1 --> to
*/
.globl rt_hw_context_switch
rt_hw_context_switch:
sw a0, rt_interrupt_from_thread, a4 /*set rt_interrupt_from_thread*/
sw a1, rt_interrupt_to_thread, a4 /*set rt_interrupt_to_thread*/
li a5, 1
sw a5, rt_thread_switch_interrupt_flag, a4 /*rt_thread_switch_interrupt_flag = 1*/
SWINT /*kick soft interrupt*/
ret
/*
* void rt_switch_to_thread(void);
* r0 --> to
*/
.globl rt_switch_to_thread
rt_switch_to_thread:
lw a0, rt_interrupt_from_thread
lw a5, rt_cur_thread_sp
sw a5, 0(a0)
lw a0, rt_interrupt_to_thread
lw a5, 0(a0)
sw a5, rt_cur_thread_sp, a4
ret
/*
* void rt_hw_context_switch_interrupt(rt_uint32 from, rt_uint32 to);
* a0 --> from
* a1 --> to
*/
.global rt_hw_context_switch_interrupt
rt_hw_context_switch_interrupt:
lw a5, rt_thread_switch_interrupt_flag
bnez a5, _reswitch
li a5, 0x01
sw a5, rt_thread_switch_interrupt_flag, a4
sw a0, rt_interrupt_from_thread, a4 /*set rt_interrupt_from_thread*/
_reswitch:
sw a1, rt_interrupt_to_thread, a4 /*set rt_interrupt_to_thread*/
ret
//
.global rt_soft_isr
rt_soft_isr:
li a5, 0x4 // PICPND = BIT(IRQ_SW_VECTOR); 清软中断Pending
sw a5, PICPND(zero)
ret
.globl low_prio_irq
low_prio_irq:
save_context
lw a5, rt_interrupt_nest
bnez a5, _low_prio_irq_exit
lw a5, cpu_irq_comm_hook
jalr a5
lw a5, rt_thread_switch_interrupt_flag
beqz a5, _low_prio_irq_exit // if (rt_thread_switch_interrupt_flag)
jal rt_switch_to_thread
sw zero, rt_thread_switch_interrupt_flag, a4 // rt_thread_switch_interrupt_flag = 0;
_low_prio_irq_exit:
restore_context