int ethernet_send() {
#if NEW_LOGIC
if(tx_produce_offset < 0) { // no buffer active
return -1;
}
// ensure there is a link
if(!ethernet_link()) {
return -2;
}
// we have been writing in to a buffer, so finalise it
int size = tx_produce_offset;
int index = LPC_EMAC->TxProduceIndex;
txdesc[index].Ctrl = (tx_produce_offset-1) | (TCTRL_INT | TCTRL_LAST);
// Increment ProduceIndex to allow it to be sent
// We can only do this if the next slot is free
int next = rinc(index, NUM_TX_FRAG);
while(next == LPC_EMAC->TxConsumeIndex) {
for(int i=0; i<1000; i++) { __NOP(); }
}
LPC_EMAC->TxProduceIndex = next;
tx_produce_offset = -1;
return size;
#else
int s = send_size;
txdesc[send_idx].Ctrl = (send_doff-1) | (TCTRL_INT | TCTRL_LAST);
send_idx = rinc(send_idx, NUM_TX_FRAG);
LPC_EMAC->TxProduceIndex = send_idx;
send_doff = 0;
send_idx = -1;
send_size = 0;
return s;
#endif
}
int ethernet_read(char *data, int dlen) {
#if NEW_LOGIC
// Check we have a valid buffer to read
if(rx_consume_offset < 0) {
return 0;
}
// Assume 1 fragment block
uint32_t info = rxstat[LPC_EMAC->RxConsumeIndex].Info;
int size = (info & RINFO_SIZE) + 1 - 4; // exclude checksum
int remaining = size - rx_consume_offset;
int requested = dlen;
int ncopy = min(remaining, requested);
void *psrc = (void *)(rxdesc[LPC_EMAC->RxConsumeIndex].Packet + rx_consume_offset);
void *pdst = (void *)(data);
if(data != NULL && ncopy > 0) {
memcpy(pdst, psrc, ncopy);
}
rx_consume_offset += ncopy;
return ncopy;
#else
int slen;
int copy = 0;
unsigned int more;
unsigned int info;
void *pdst, *psrc;
int doff = 0;
if((uint32_t)receive_idx == LPC_EMAC->RxProduceIndex || receive_idx == -1) {
return 0;
}
do {
info = rxstat[receive_idx].Info;
more = !(info & RINFO_LAST_FLAG);
slen = (info & RINFO_SIZE) + 1;
if(slen > ethernet_MTU_SIZE || (info & RINFO_ERR_MASK)) {
/* Invalid frame, ignore it and free buffer. */
receive_idx = rinc(receive_idx, NUM_RX_FRAG);
} else {
copy = min(slen - receive_soff, dlen - doff);
psrc = (void *)(rxdesc[receive_idx].Packet + receive_soff);
pdst = (void *)(data + doff);
if(data != NULL) {
/* check if Buffer available */
memcpy(pdst, psrc, copy);
}
receive_soff += copy;
doff += copy;
if((more && (receive_soff == slen))) {
receive_idx = rinc(receive_idx, NUM_RX_FRAG);
receive_soff = 0;
}
}
} while(more && !(doff == dlen) && !receive_soff);
return doff;
#endif
}
int ethernet_write(const char *data, int slen) {
#if NEW_LOGIC
if(tx_produce_offset < 0) { // mark as active if not already
tx_produce_offset = 0;
}
int index = LPC_EMAC->TxProduceIndex;
int remaining = ETH_MAX_FLEN - tx_produce_offset - 4; // bytes written plus checksum
int requested = slen;
int ncopy = min(remaining, requested);
void *pdst = (void *)(txdesc[index].Packet + tx_produce_offset);
void *psrc = (void *)(data);
if(ncopy > 0 ){
if(data != NULL) {
memcpy(pdst, psrc, ncopy);
} else {
memset(pdst, 0, ncopy);
}
}
tx_produce_offset += ncopy;
return ncopy;
#else
void *pdst, *psrc;
const int dlen = ETH_FRAG_SIZE;
int copy = 0;
int soff = 0;
if(send_idx == -1) {
send_idx = LPC_EMAC->TxProduceIndex;
}
if(slen + send_doff > ethernet_MTU_SIZE) {
return -1;
}
do {
copy = min(slen - soff, dlen - send_doff);
pdst = (void *)(txdesc[send_idx].Packet + send_doff);
psrc = (void *)(data + soff);
if(send_doff + copy > ETH_FRAG_SIZE) {
txdesc[send_idx].Ctrl = (send_doff-1) | (TCTRL_INT);
send_idx = rinc(send_idx, NUM_TX_FRAG);
send_doff = 0;
}
if(data != NULL) {
memcpy(pdst, psrc, copy);
} else {
memset(pdst, 0, copy);
}
soff += copy;
send_doff += copy;
send_size += copy;
} while(soff != slen);
return soff;
#endif
}
