interrupt distribution on A53 processor

Hi,

     Linux Kernel 4.9

     Processor a53

      SMP 64 Bit linux image

Issue seen:- Ethernet interrupts are seen arriving only on core0 ONLY, though core0 is completely occupied by other interrupts.

moving ethernet interrupts to other core via smp_affinity, helps drastic reduction in latency [increase in output/Transmi packets per second]

questions

1. if i understand correctly there is GIC based distributor inside ARM processor

2. my dts does init the GIC

3. Is there any config or setting required in Linux build [any change in dts or CONFIG in  linux ]to ENABLE interrupt distributor?

4. my understanding was SMP Linux itself defaults to distribution in interrupts across cores,

please point to any resource/notes in this regard

Thanks

RC Reddy