HAL_FIQClear
Hardware Abstraction Layer
HAL entry points from RISC OS
» HAL_FIQClear
HAL_FIQClear
(HAL entry #9)
void HAL_FIQClear(int device)
| Entry | |
|---|---|
| device | Device number to clear interrupt state for |
| Exit | |
|---|---|
| - |
Use
If the interrupt controller does not latch interrupt sources, this call does not need to be implemented.
If the interrupt controller does latch interrupt sources, this call must be implemented, to provide a way for those latches to be reset once the device has been serviced. Otherwise the ARM may receive spurious FIQs for devices which are no longer interrupting, or the system may become completely stuck attempting to serve the phantom FIQ.
RISC OS code which uses FIQs must make sure to call HAL_FIQClear once they have serviced the interrupting device – the OS will not call it for you.
See also
Information sources: Kernel.Docs.HAL.MoreEnts, HAL.Tungsten.s.Interrupts, HAL.OMAP3.s.Interrupts in CVS
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