See related discussion in e.g. here:
- long discussion in Feb2017 starting from Netgear R7800 exploration (IPQ8065, QCA9984)
In short, echo affinity to IRQs one by one, like:
echo 2 >/proc/irq/30/smp_affinity
Read them with:
cat /proc/irq/31/smp_affinity
2
Bitmask.
1 = core 0
2 = core 1
4 = core 2 ... Etc.
3 = both core 0 and 1