int32_t HAL_TimerIRQStatus(int32_t timer)
|0||Timer is not interrupting|
|non-0||Timer is interrupting|
This entry was originally added to support a platform where there were multiple timers, all multiplexed through the same interrupt in the main interrupt controller.
To allow for the possibility of other such platforms in future, if you are writing timer interrupt code, you should check to see whether the HAL_TimerDevice indicates the interrupt is shared (which can be detected by bit 31 of the device number being set). If this is the case, then you must use a vectored interrupt handler, and you must check that the timer in which you are interested was responsible for the interrupt by using this HAL entry.
Note that the original port was never completed, so at the time of writing, although this entry was implemented in the HAL, the Timer0 code in the kernel does not support shared timer interrupts yet.