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|
;/*
; * Copyright (c) 2006-2022, RT-Thread Development Team
; *
; * SPDX-License-Identifier: Apache-2.0
; *
; * Change Logs:
; * Date Author Notes
; * 2009-01-20 Bernard first version
; */
NOINT EQU 0xc0 ; disable interrupt in psr
AREA |.text|, CODE, READONLY, ALIGN=2
ARM
REQUIRE8
PRESERVE8
;/*
; * rt_base_t rt_hw_interrupt_disable();
; */
rt_hw_interrupt_disable PROC
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);
; */
rt_hw_interrupt_enable PROC
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
; */
rt_hw_context_switch PROC
EXPORT rt_hw_context_switch
STMFD sp!, {lr} ; push pc (lr should be pushed in place of PC)
STMFD sp!, {r0-r12, lr} ; push lr & register file
MRS r4, cpsr
STMFD sp!, {r4} ; push cpsr
MRS r4, spsr
STMFD sp!, {r4} ; push spsr
STR sp, [r0] ; store sp in preempted tasks TCB
LDR sp, [r1] ; get new task stack pointer
LDMFD sp!, {r4} ; pop new task spsr
MSR spsr_cxsf, r4
LDMFD sp!, {r4} ; pop new task cpsr
MSR cpsr_cxsf, r4
LDMFD sp!, {r0-r12, lr, pc} ; pop new task r0-r12, lr & pc
ENDP
;/*
; * void rt_hw_context_switch_to(rt_uint32 to);
; * r0 --> to
; */
rt_hw_context_switch_to PROC
EXPORT rt_hw_context_switch_to
LDR sp, [r0] ; get new task stack pointer
LDMFD sp!, {r4} ; pop new task spsr
MSR spsr_cxsf, r4
LDMFD sp!, {r4} ; pop new task cpsr
MSR cpsr_cxsf, r4
LDMFD sp!, {r0-r12, lr, pc} ; pop new task r0-r12, lr & pc
ENDP
;/*
; * void rt_hw_context_switch_interrupt(rt_uint32 from, rt_uint32 to);
; */
IMPORT rt_thread_switch_interrupt_flag
IMPORT rt_interrupt_from_thread
IMPORT rt_interrupt_to_thread
rt_hw_context_switch_interrupt PROC
EXPORT rt_hw_context_switch_interrupt
LDR r2, =rt_thread_switch_interrupt_flag
LDR r3, [r2]
CMP r3, #1
BEQ _reswitch
MOV r3, #1 ; set rt_thread_switch_interrupt_flag to 1
STR r3, [r2]
LDR r2, =rt_interrupt_from_thread ; set rt_interrupt_from_thread
STR r0, [r2]
_reswitch
LDR r2, =rt_interrupt_to_thread ; set rt_interrupt_to_thread
STR r1, [r2]
BX lr
ENDP
END
|
