nhi_dmamem_alloc
struct nhi_dmamem *nhi_dmamem_alloc(bus_dma_tag_t, bus_size_t,
sc->sc_tx_ring = nhi_dmamem_alloc(sc->sc_dmat,
sc->sc_rx_ring = nhi_dmamem_alloc(sc->sc_dmat,
rxb = nhi_dmamem_alloc(sc->sc_dmat, 4096, sizeof(uint32_t));