Local interrupts have higher priority than Global interrupts. If a Local and Global interrupt arrive in the same cycle, the Local interrupt is handled if enabled. Priorities of Local interrupts are determined by the Local interrupt ID, Local Interrupt 47 being the highest priority. For example, if Local Interrupt 47 and 6 arrive in the same cycle, Local Interrupt 47 is handled.
Exception code of the Local Interrupt 47 is also the highest and occupies the last slot in the interrupt vector table. This unique position in the vector table allows the interrupt handler of the Local Interrupt 47 to be placed in-line instead of a jump instruction. The jump instruction is required for other interrupts when operating in Vectored mode. Hence, Local Interrupt 47 must be used for the most critical interrupt in the system.
CPU Core Complex interrupts are prioritized in the following decreasing order of priority:
Individual priorities of Global interrupts are determined by the PLIC, see Platform Level Interrupt Controller.