ucosii任务切换问题

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楼主 | 2009-12-19 13:01 | 只看该作者回帖奖励

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ucosii, ST, DSP, tc, RS

我在s3c2440上移植ucos时出现中断后任务不能切换的问题，请教一下
代码如下:

OSTickISR
stmfd sp!,{r0-r3}
mov r1,sp
add sp,sp,#16 ;pop r0-r3

sub r2,lr,#4 ;get pc in svc mode

mrs r3, spsr ;get cpsr in svc mode
msr cpsr_c,#(NOINT|SVCMODE)  ;switch to SVC mode
stmfd sp!,{r2}
stmfd sp!,{lr}
stmfd sp!,{r4-r12}

ldmfd r1!,{r4-r7}
stmfd sp!,{r4-r7}
stmfd sp!,{r3}
mrs r4, spsr
stmfd sp!,{r4}

;bl OSIntEnter
ldr r0, =OSIntNesting
ldrb r1, [r0]
add r1, r1,#1
strb r1, [r0]
cmp r1, #1
bne ISR1
bl OSTest2Hook
ldr r4, =OSTCBCur
ldr r5, [r4]
str sp, [r5]
ISR1
ldr r0, =SRCPND
mov r1, #BIT_TIMER4
str r1, [r0]
ldr r0, =INTPND
ldr r1,[r0]
str r1, [r0]

bl OSTimeTick

bl OSIntExit
bl OSTest1Hook
ldmfd sp!,r4
msr spsr_cxsf, r4
ldmfd sp!,{r4}
msr cpsr_cxsf, r4
ldmfd sp!,{r0-r12,lr,pc}

OSIntCtxSw
;call user definable OSTaskSwHook()
bl OSTaskSwHook

;OSPrioCur = OSPrioHighRdy
ldr  r4 , =OSPrioCur
ldr  r5 , =OSPrioHighRdy
ldrb r5 , [r5]
strb r5 , [r4]

;OSTCBCur = OSTCBHighRdy
ldr r4 , =OSTCBCur
ldr r5 , =OSTCBHighRdy
ldr r5 , [r5]
str r5 , [r4]
;stack pointer = OSTCBHighRdy->OSTCBStkPtr
ldr r4 , =OSTCBHighRdy
ldr r4 , [r4]
ldr sp , [r4]

;restore tasks mode registers
ldmfd sp!,{r4}
msr spsr_cxsf, r4
ldmfd sp!,{r4}
msr cpsr_cxsf, r4

;return in new task context
ldmfd sp!,{r0-r12,lr,pc}

使用特权