As the Reference Manual for S32K148 says, there is only one TX descriptor ring.
I am researching the feasibility of splitting ENET TX descriptor ring into 2 pools. Each pool to be reserved for different type of traffic. I did a simple test, in which I am allocating 8 TX descriptors in the ring. The last descriptor wraps to 1st.
When sending packets I am filling only first 4 descriptors. The result is that ENET sends only first 4 frames and stops after this. This would mean that it expects the descriptors to be filled continuously and if it encounters an empty descriptor (with descriptor's "R - ready" field set to 0) it stops.
Is there a way to change this behavior? Like e.g. get notified when empty descriptor is reached and trigger ENET to check next descriptor in the ring?