From Florian Fainelli
Sent: 31 January 2017 20:33
On 01/31/2017 11:03 AM, Iyappan Subramanian wrote:

quoted

This patch adds,
    - Transmit
    - Transmit completion poll
    - Receive poll
    - NAPI handler

and enables the driver.

Signed-off-by: Iyappan Subramanian <redacted>
Signed-off-by: Keyur Chudgar <redacted>
---

quoted

+
+	tx_ring = pdata->tx_ring;
+	tail = tx_ring->tail;
+	len = skb_headlen(skb);
+	raw_desc = &tx_ring->raw_desc[tail];
+
+	/* Tx descriptor not available */
+	if (!GET_BITS(E, le64_to_cpu(raw_desc->m0)) ||
+	    GET_BITS(PKT_SIZE, le64_to_cpu(raw_desc->m0)))
+		return NETDEV_TX_BUSY;

Aren't you supposed to detect 'ring full' and stop the code
giving you packets to transmit.

quoted

+
+	/* Packet buffers should be 64B aligned */

Is that really a requirement of the hardware?
Almost all ethernet frames are 4n+2 aligned.

quoted

+	pkt_buf = dma_alloc_coherent(dev, XGENE_ENET_STD_MTU, &dma_addr,
+				     GFP_ATOMIC);
+	if (unlikely(!pkt_buf))
+		goto out;

Can't you obtain a DMA-API mapping for skb->data and pass it down to the
hardware? This copy here is inefficient.

quoted

+
+	memcpy(pkt_buf, skb->data, len);

You really need to verify that the len <= XGENE_ENET_STD_MTU.

Isn't this code only transmitting the 'head' of the packet?
What about the fragments??
...
	David