static void
ffec_rxfinish_locked(struct ffec_softc *sc)
{
struct ffec_hwdesc *desc;
int len;
boolean_t produced_empty_buffer;
FFEC_ASSERT_LOCKED(sc);
produced_empty_buffer = false;
for (;;) {
desc = &sc->rxdesc_ring[sc->rx_idx];
if (desc->flags_len & FEC_RXDESC_EMPTY)
break;
produced_empty_buffer = true;
len = (desc->flags_len & FEC_RXDESC_LEN_MASK);
if (len < 64) {
/*
* Just recycle the descriptor and continue. .
*/
ffec_setup_rxdesc(sc, sc->rx_idx,
sc->rxdesc_ring[sc->rx_idx].buf_paddr);
} else if ((desc->flags_len & FEC_RXDESC_L) == 0) {
/*
* The entire frame is not in this buffer. Impossible.
* Recycle the descriptor and continue.
*
* XXX what's the right way to handle this? Probably we
* should stop/init the hardware because this should
* just really never happen when we have buffers bigger
* than the maximum frame size.
*/
device_printf(sc->dev,
"fec_rxfinish: received frame without LAST bit set");
ffec_setup_rxdesc(sc, sc->rx_idx,
sc->rxdesc_ring[sc->rx_idx].buf_paddr);
} else if (desc->flags_len & FEC_RXDESC_ERROR_BITS) {
/*
* Something went wrong with receiving the frame, we
* don't care what (the hardware has counted the error
* in the stats registers already), we just reuse the
* same mbuf, which is still dma-mapped, by resetting
* the rx descriptor.
*/
ffec_setup_rxdesc(sc, sc->rx_idx,
sc->rxdesc_ring[sc->rx_idx].buf_paddr);
} else {
/*
* Normal case: a good frame all in one buffer.
*/
ffec_rxfinish_onebuf(sc, len);
}
sc->rx_idx = next_rxidx(sc, sc->rx_idx);
}
if (produced_empty_buffer) {
WR4(sc, FEC_RDAR_REG, FEC_RDAR_RDAR);
}
}
inline static uint32_t
ffec_setup_rxdesc(struct ffec_softc *sc, int idx, bus_addr_t paddr)
{
uint32_t nidx;
/*
* The hardware requires 32-bit physical addresses. We set up the dma
* tag to indicate that, so the cast to uint32_t should never lose
* significant bits.
*/
nidx = next_rxidx(sc, idx);
sc->rxdesc_ring[idx].buf_paddr = (uint32_t)paddr;
sc->rxdesc_ring[idx].flags_len = FEC_RXDESC_EMPTY |
((nidx == 0) ? FEC_RXDESC_WRAP : 0);
return (nidx);
}