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.global rt_hw_interrupt_disable
.global rt_hw_interrupt_enable
.global rt_hw_context_switch
.global rt_hw_context_switch_to
.global rt_hw_context_switch_interrupt
.equ NOINT, 0xc0
/*
* rt_base_t rt_hw_interrupt_disable();
�ر��жϣ��ر�ǰ����CPSR�Ĵ���ֵ
*/
rt_hw_interrupt_disable:
//EXPORT rt_hw_interrupt_disable
MRS r0, cpsr
ORR r1, r0, #NOINT
MSR cpsr_c, r1
BX lr
//ENDP
/*
* void rt_hw_interrupt_enable(rt_base_t level);
�ָ��ж�״̬
*/
rt_hw_interrupt_enable:
//EXPORT rt_hw_interrupt_enable
MSR cpsr_c, r0
BX lr
//ENDP
/*
* void rt_hw_context_switch(rt_uint32 from, rt_uint32 to);
* r0 --> from
* r1 --> to
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*/
rt_hw_context_switch:
//EXPORT rt_hw_context_switch
STMFD sp!, {lr} /* push pc (lr should be pushed in place of PC) */
/* ��LR�Ĵ���ѹ��ջ������������غ����һ��ִ�д��� */
STMFD sp!, {r0-r12, lr} /* push lr & register file */
/* ��R0 �C R12�Լ�LRѹ��ջ */
MRS r4, cpsr /* ��ȡCPSR�Ĵ�����R4�Ĵ��� */
STMFD sp!, {r4} /* push cpsr */
/* ��R4�Ĵ���ѹջ������һָ��ȡ����CPSR�Ĵ����� */
MRS r4, spsr /* ��ȡSPSR�Ĵ�����R4�Ĵ��� */
STMFD sp!, {r4} /* push spsr */
/* ��R4�Ĵ���ѹջ����SPSR�Ĵ����� */
STR sp, [r0] /* store sp in preempted tasks TCB */
/* ��ջָ����µ�TCB��sp������R0����˺��� */
/* �����ﻻ���̵߳������Ķ�������ջ�� */
LDR sp, [r1] /* get new task stack pointer */
/* �����л����̵߳�TCB��sp */
/* ���л����̵߳�ջ�лָ������ģ�����ͱ����ʱ��պ��෴ */
LDMFD sp!, {r4} /* pop new task spsr */
/* ��ջ��R4�Ĵ�����������SPSR�Ĵ����� */
MSR spsr_cxsf, r4 /* �ָ�SPSR�Ĵ��� */
LDMFD sp!, {r4} /* pop new task cpsr */
/* ��ջ��R4�Ĵ�����������CPSR�Ĵ����� */
MSR cpsr_cxsf, r4 /* �ָ�CPSR�Ĵ��� */
LDMFD sp!, {r0-r12, lr, pc} /* pop new task r0-r12, lr & pc */
/* ��R0 �C R12��LR��PC���лָ� */
//ENDP
rt_hw_context_switch_to:
//EXPORT rt_hw_context_switch_to
LDR sp, [r0] /* get new task stack pointer */
/* ����л����̵߳�SPָ�� */
LDMFD sp!, {r4} /* pop new task spsr */
/* ��ջR4�Ĵ�����������SPSR�Ĵ���ֵ�� */
MSR spsr_cxsf, r4 /* �ָ�SPSR�Ĵ��� */
LDMFD sp!, {r4} /* pop new task cpsr */
/* ��ջR4�Ĵ�����������CPSR�Ĵ���ֵ�� */
MSR cpsr_cxsf, r4 /* �ָ�CPSR�Ĵ��� */
LDMFD sp!, {r0-r12, lr, pc} /* pop new task r0-r12, lr & pc */
/* �ָ�R0 �C R12��LR��PC�Ĵ��� */
//ENDP
rt_hw_context_switch_interrupt:
//EXPORT rt_hw_context_switch_interrupt
LDR r2, =rt_thread_switch_interrupt_flag
LDR r3, [r2] /* �����ж����л����µ�ַ */
CMP r3, #1 /* ���� 1 ��*/
BEQ _reswitch /* �������1����ת��_reswitch*/
MOV r3, #1 /* set rt_thread_switch_interrupt_flag to 1*/
/* �����ж����л���־λ1 */
STR r3, [r2] /* */
LDR r2, =rt_interrupt_from_thread /* set rt_interrupt_from_thread*/
STR r0, [r2] /* �����л����߳�ջָ��*/
_reswitch:
LDR r2, =rt_interrupt_to_thread /* set rt_interrupt_to_thread*/
STR r1, [r2] /* �����л����߳�ջָ��*/
BX lr
//ENDP
//END
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