/**
* \brief Send a frame splitted into buffers. If the frame size is larger than transfer buffer size
* error returned. If frame transfer status is monitored, specify callback for each frame.
* \param pGmacd Pointer to GMAC Driver instance.
* \param sgl Pointer to a scatter-gather list describing the buffers of the ethernet frame.
*/
uint8_t GMACD_SendSG(sGmacd *pGmacd,
const sGmacSGList *sgl,
fGmacdTransferCallback fTxCb,
gmacQueList_t queIdx)
{
Gmac *pHw = pGmacd->pHw;
sGmacTxDescriptor *pTd = pGmacd->queueList[queIdx].pTxD;
sGmacTxDescriptor *pTxTd;
uint16_t wTxPos, wTxHead;
int i;
TRACE_DEBUG("%s\n\r", __FUNCTION__);
/* Check parameter */
if (!sgl->len) {
TRACE_ERROR("%s:: ethernet frame is empty.\r\n", __FUNCTION__);
return GMACD_PARAM;
}
if (sgl->len >= pGmacd->queueList[queIdx].wTxListSize) {
TRACE_ERROR("%s: ethernet frame has too many buffers.\r\n", __FUNCTION__);
return GMACD_PARAM;
}
/* Check available space */
if (GCIRC_SPACE(pGmacd->queueList[queIdx].wTxHead, pGmacd->queueList[queIdx].wTxTail, pGmacd->queueList[queIdx].wTxListSize) < (int)sgl->len)
return GMACD_TX_BUSY;
/* Tag end of TX queue */
wTxHead = fixed_mod(pGmacd->queueList[queIdx].wTxHead + sgl->len, pGmacd->queueList[queIdx].wTxListSize);
wTxPos = wTxHead;
pGmacd->queueList[queIdx].fTxCbList[wTxPos] = NULL;
pTxTd = &pTd[wTxPos];
pTxTd->status.val = GMAC_TX_USED_BIT;
/* Update buffer descriptors in reverse order to avoid a race
* condition with hardware.
*/
for (i = (int)(sgl->len-1); i >= 0; --i) {
const sGmacSG *sg = &sgl->sg[i];
uint32_t status;
if (sg->size > GMAC_TX_UNITSIZE) {
TRACE_ERROR("%s: buffer size is too big.\r\n", __FUNCTION__);
return GMACD_PARAM;
}
if (wTxPos == 0)
wTxPos = pGmacd->queueList[queIdx].wTxListSize-1;
else
wTxPos--;
/* Reset TX callback */
pGmacd->queueList[queIdx].fTxCbList[wTxPos] = NULL;
pTxTd = &pTd[wTxPos];
#ifdef GMAC_ZERO_COPY
/** Update buffer descriptor address word:
* MUST be done before status word to avoid a race condition.
*/
pTxTd->addr = (uint32_t)sg->pBuffer;
#else
/* Copy data into transmittion buffer */
if (sg->pBuffer && sg->size)
memcpy((void *)pTxTd->addr, sg->pBuffer, sg->size);
#endif
/* Compute buffer descriptor status word */
status = sg->size & GMAC_LENGTH_FRAME;
if (i == (int)(sgl->len-1)) {
status |= GMAC_TX_LAST_BUFFER_BIT;
pGmacd->queueList[queIdx].fTxCbList[wTxPos] = fTxCb;
}
if (wTxPos == pGmacd->queueList[queIdx].wTxListSize-1)
status |= GMAC_TX_WRAP_BIT;
/* Update buffer descriptor status word: clear USED bit */
pTxTd->status.val = status;
/* Make newly initialized descriptor visible to hardware */
memory_barrier();
}
/* Update TX ring buffer pointers */
pGmacd->queueList[queIdx].wTxHead = wTxHead;
memory_barrier();
/* Now start to transmit if it is not already done */
GMAC_TransmissionStart(pHw);
return GMACD_OK;
}
/**
* \brief Send a frame splitted into buffers. If the frame size is larger than transfer buffer size
* error returned. If frame transfer status is monitored, specify callback for each frame.
* \param gmacd Pointer to GMAC Driver instance.
* \param sgl Pointer to a scatter-gather list describing the buffers of the ethernet frame.
* \param fTxCb Pointer to callback function.
*/
uint8_t gmacd_send_sg(struct _gmacd* gmacd, uint8_t queue,
const struct _gmac_sg_list* sgl, gmacd_callback_t callback)
{
Gmac* gmac = gmacd->gmac;
struct _gmacd_queue* q = &gmacd->queues[queue];
struct _gmac_desc* desc;
uint16_t idx, tx_head;
int i;
if (callback && !q->tx_callbacks) {
trace_error("Cannot set send callback, no tx_callbacks "\
"buffer configured for queue %u", queue);
}
/* Check parameter */
if (!sgl->size) {
trace_error("gmacd_send_sg: ethernet frame is empty.\r\n");
return GMACD_PARAM;
}
if (sgl->size >= q->tx_size) {
trace_error("gmacd_send_sg: ethernet frame has too many buffers.\r\n");
return GMACD_PARAM;
}
/* Check available space */
if (RING_SPACE(q->tx_head, q->tx_tail, q->tx_size) < sgl->size) {
trace_error("gmacd_send_sg: not enough free buffers in TX queue.\r\n");
return GMACD_TX_BUSY;
}
/* Tag end of TX queue */
tx_head = fixed_mod(q->tx_head + sgl->size, q->tx_size);
idx = tx_head;
if (q->tx_callbacks)
q->tx_callbacks[idx] = NULL;
desc = &q->tx_desc[idx];
desc->status |= GMAC_TX_STATUS_USED;
/* Update buffer descriptors in reverse order to avoid a race
* condition with hardware.
*/
for (i = sgl->size - 1; i >= 0; i--) {
const struct _gmac_sg *sg = &sgl->entries[i];
uint32_t status;
if (sg->size > GMAC_TX_UNITSIZE) {
trace_error("gmacd_send_sg: buffer size is too big.\r\n");
return GMACD_PARAM;
}
RING_DEC(idx, q->tx_size);
/* Reset TX callback */
if (q->tx_callbacks)
q->tx_callbacks[idx] = NULL;
desc = &q->tx_desc[idx];
/* Copy data into transmittion buffer */
if (sg->buffer && sg->size) {
memcpy((void*)desc->addr, sg->buffer, sg->size);
l2cc_clean_region(desc->addr, desc->addr + sg->size);
}
/* Compute buffer descriptor status word */
status = sg->size & GMAC_RX_STATUS_LENGTH_MASK;
if (i == (sgl->size - 1)) {
status |= GMAC_TX_STATUS_LASTBUF;
if (q->tx_callbacks)
q->tx_callbacks[idx] = callback;
}
if (idx == (q->tx_size - 1)) {
status |= GMAC_TX_STATUS_WRAP;
}
/* Update buffer descriptor status word: clear USED bit */
desc->status = status;
DSB();
}
/* Update TX ring buffer pointers */
q->tx_head = tx_head;
/* Now start to transmit if it is not already done */
gmac_start_transmission(gmac);
return GMACD_OK;
}
