23 lines
635 B
ArmAsm
23 lines
635 B
ArmAsm
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.text
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.thumb
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.align 2
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.global StartCritical
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.global EndCritical
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// *********** StartCritical ************************
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//make a copy of previous I bit, disable interrupts
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// inputs : none
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// outputs : R0=previous I bit
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StartCritical:
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MRS R0, PRIMASK // save old status
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CPSID I // mask all (except faults)
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BX LR
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// *********** EndCritical ************************
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// using the copy of previous I bit, restore I bit to previous value
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// inputs : R0=previous I bit
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// outputs : none
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EndCritical:
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MSR PRIMASK, R0
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BX LR
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