Esempio n. 1
0
/*
 * Receives a frame.
 */
static struct pbuf *low_level_input(struct netif *netif) {
  MACReceiveDescriptor rd;
  struct pbuf *p, *q;
  u16_t len;

  (void)netif;
  if (macWaitReceiveDescriptor(&ETHD1, &rd, TIME_IMMEDIATE) == MSG_OK) {
    len = (u16_t)rd.size;

#if ETH_PAD_SIZE
    len += ETH_PAD_SIZE;        /* allow room for Ethernet padding */
#endif

    /* We allocate a pbuf chain of pbufs from the pool. */
    p = pbuf_alloc(PBUF_RAW, len, PBUF_POOL);

    if (p != NULL) {

#if ETH_PAD_SIZE
      pbuf_header(p, -ETH_PAD_SIZE); /* drop the padding word */
#endif

      /* Iterates through the pbuf chain. */
      for(q = p; q != NULL; q = q->next)
        macReadReceiveDescriptor(&rd, (uint8_t *)q->payload, (size_t)q->len);
      macReleaseReceiveDescriptor(&rd);

#if ETH_PAD_SIZE
      pbuf_header(p, ETH_PAD_SIZE); /* reclaim the padding word */
#endif

      LINK_STATS_INC(link.recv);
    }
    else {
      macReleaseReceiveDescriptor(&rd);
      LINK_STATS_INC(link.memerr);
      LINK_STATS_INC(link.drop);
    }
    return p;
  }
  return NULL;
}
Esempio n. 2
0
/*
 * uIP receive function wrapping the EMAC function.
 */
static size_t network_device_read(void) {
  MACReceiveDescriptor rd;
  size_t size;

  if (macWaitReceiveDescriptor(&ETHD1, &rd, TIME_IMMEDIATE) != RDY_OK)
    return 0;
  size = rd.size;
  macReadReceiveDescriptor(&rd, uip_buf, size);
  macReleaseReceiveDescriptor(&rd);
  return size;
}