/**
* Should allocate a pbuf and transfer the bytes of the incoming
* packet from the interface into the pbuf.
*
* @param netif the lwip network interface structure for this ethernetif
* @return a pbuf filled with the received packet (including MAC header)
* NULL on memory error
*/
static struct pbuf *
low_level_input(struct netif *netif)
{
struct pbuf *p, *q;
u16_t len;
if(EMAC_GetBufferSts(EMAC_RX_BUFF) == EMAC_BUFF_EMPTY)
return NULL;
/* Obtain the size of the packet and put it into the "len"
variable. */
len = EMAC_GetRxFrameSize();
#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
/* We iterate over the pbuf chain until we have read the entire
* packet into the pbuf. */
uint8_t *ptr = (uint8_t *)EMAC_GetRxBuffer();
for(q = p; q != NULL; q = q->next) {
MEMCPY(q->payload, ptr, q->len);
ptr += q->len;
}
EMAC_UpdateRxConsumeIndex();
#if ETH_PAD_SIZE
pbuf_header(p, ETH_PAD_SIZE); /* reclaim the padding word */
#endif
LINK_STATS_INC(link.recv);
} else {
// drop packet();
LINK_STATS_INC(link.memerr);
LINK_STATS_INC(link.drop);
}
return p;
}
/*********************************************************************//**
* @brief
* @param[in]
* @return
**********************************************************************/
unsigned int Rdy4Tx(void)
{
return ((EMAC_GetBufferSts(EMAC_TX_BUFF) == EMAC_BUFF_EMPTY) ? 1:0);
}
