static int macb_recv(struct eth_device *netdev)
{
struct macb_device *macb = to_macb(netdev);
unsigned int rx_tail = macb->rx_tail;
void *buffer;
int length;
int wrapped = 0;
u32 status;
for (;;) {
macb_invalidate_ring_desc(macb, RX);
if (!(macb->rx_ring[rx_tail].addr & RXADDR_USED))
return -1;
status = macb->rx_ring[rx_tail].ctrl;
if (status & RXBUF_FRAME_START) {
if (rx_tail != macb->rx_tail)
reclaim_rx_buffers(macb, rx_tail);
wrapped = 0;
}
if (status & RXBUF_FRAME_END) {
buffer = macb->rx_buffer + 128 * macb->rx_tail;
length = status & RXBUF_FRMLEN_MASK;
macb_invalidate_rx_buffer(macb);
if (wrapped) {
unsigned int headlen, taillen;
headlen = 128 * (MACB_RX_RING_SIZE
- macb->rx_tail);
taillen = length - headlen;
memcpy((void *)NetRxPackets[0],
buffer, headlen);
memcpy((void *)NetRxPackets[0] + headlen,
macb->rx_buffer, taillen);
buffer = (void *)NetRxPackets[0];
}
NetReceive(buffer, length);
if (++rx_tail >= MACB_RX_RING_SIZE)
rx_tail = 0;
reclaim_rx_buffers(macb, rx_tail);
} else {
if (++rx_tail >= MACB_RX_RING_SIZE) {
wrapped = 1;
rx_tail = 0;
}
}
barrier();
}
return 0;
}
static int _macb_recv(struct macb_device *macb, uchar **packetp)
{
unsigned int next_rx_tail = macb->next_rx_tail;
void *buffer;
int length;
u32 status;
macb->wrapped = false;
for (;;) {
macb_invalidate_ring_desc(macb, RX);
if (!(macb->rx_ring[next_rx_tail].addr & RXADDR_USED))
return -EAGAIN;
status = macb->rx_ring[next_rx_tail].ctrl;
if (status & RXBUF_FRAME_START) {
if (next_rx_tail != macb->rx_tail)
reclaim_rx_buffers(macb, next_rx_tail);
macb->wrapped = false;
}
if (status & RXBUF_FRAME_END) {
buffer = macb->rx_buffer + 128 * macb->rx_tail;
length = status & RXBUF_FRMLEN_MASK;
macb_invalidate_rx_buffer(macb);
if (macb->wrapped) {
unsigned int headlen, taillen;
headlen = 128 * (MACB_RX_RING_SIZE
- macb->rx_tail);
taillen = length - headlen;
memcpy((void *)net_rx_packets[0],
buffer, headlen);
memcpy((void *)net_rx_packets[0] + headlen,
macb->rx_buffer, taillen);
*packetp = (void *)net_rx_packets[0];
} else {
*packetp = buffer;
}
if (++next_rx_tail >= MACB_RX_RING_SIZE)
next_rx_tail = 0;
macb->next_rx_tail = next_rx_tail;
return length;
} else {
if (++next_rx_tail >= MACB_RX_RING_SIZE) {
macb->wrapped = true;
next_rx_tail = 0;
}
}
barrier();
}
}
