net: fec: Factorize the .xmit transmit function
Make the code more readable and easy to support other features like
SG, TSO, moving the common transmit function to one api.
And the patch also factorize the getting BD index to it own function.
CC: David Laight <David.Laight@ACULAB.COM>
Signed-off-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/freescale/fec.h b/drivers/net/ethernet/freescale/fec.h
index 3b8d6d1..db967a0 100644
--- a/drivers/net/ethernet/freescale/fec.h
+++ b/drivers/net/ethernet/freescale/fec.h
@@ -296,6 +296,7 @@
/* The ring entries to be free()ed */
struct bufdesc *dirty_tx;
+ unsigned short bufdesc_size;
unsigned short tx_ring_size;
unsigned short rx_ring_size;
diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c
index 802be17..ee8e547 100644
--- a/drivers/net/ethernet/freescale/fec_main.c
+++ b/drivers/net/ethernet/freescale/fec_main.c
@@ -287,6 +287,12 @@
return (new_bd < base) ? (new_bd + ring_size) : new_bd;
}
+static int fec_enet_get_bd_index(struct bufdesc *base, struct bufdesc *bdp,
+ struct fec_enet_private *fep)
+{
+ return ((const char *)bdp - (const char *)base) / fep->bufdesc_size;
+}
+
static void *swap_buffer(void *bufaddr, int len)
{
int i;
@@ -313,8 +319,7 @@
return 0;
}
-static netdev_tx_t
-fec_enet_start_xmit(struct sk_buff *skb, struct net_device *ndev)
+static int txq_submit_skb(struct sk_buff *skb, struct net_device *ndev)
{
struct fec_enet_private *fep = netdev_priv(ndev);
const struct platform_device_id *id_entry =
@@ -329,14 +334,6 @@
status = bdp->cbd_sc;
- if (status & BD_ENET_TX_READY) {
- /* Ooops. All transmit buffers are full. Bail out.
- * This should not happen, since ndev->tbusy should be set.
- */
- netdev_err(ndev, "tx queue full!\n");
- return NETDEV_TX_BUSY;
- }
-
/* Protocol checksum off-load for TCP and UDP. */
if (fec_enet_clear_csum(skb, ndev)) {
dev_kfree_skb_any(skb);
@@ -350,16 +347,7 @@
bufaddr = skb->data;
bdp->cbd_datlen = skb->len;
- /*
- * On some FEC implementations data must be aligned on
- * 4-byte boundaries. Use bounce buffers to copy data
- * and get it aligned. Ugh.
- */
- if (fep->bufdesc_ex)
- index = (struct bufdesc_ex *)bdp -
- (struct bufdesc_ex *)fep->tx_bd_base;
- else
- index = bdp - fep->tx_bd_base;
+ index = fec_enet_get_bd_index(fep->tx_bd_base, bdp, fep);
if (((unsigned long) bufaddr) & FEC_ALIGNMENT) {
memcpy(fep->tx_bounce[index], skb->data, skb->len);
@@ -433,15 +421,43 @@
fep->cur_tx = bdp;
- if (fep->cur_tx == fep->dirty_tx)
- netif_stop_queue(ndev);
-
/* Trigger transmission start */
writel(0, fep->hwp + FEC_X_DES_ACTIVE);
return NETDEV_TX_OK;
}
+static netdev_tx_t
+fec_enet_start_xmit(struct sk_buff *skb, struct net_device *ndev)
+{
+ struct fec_enet_private *fep = netdev_priv(ndev);
+ struct bufdesc *bdp;
+ unsigned short status;
+ int ret;
+
+ /* Fill in a Tx ring entry */
+ bdp = fep->cur_tx;
+
+ status = bdp->cbd_sc;
+
+ if (status & BD_ENET_TX_READY) {
+ /* Ooops. All transmit buffers are full. Bail out.
+ * This should not happen, since ndev->tbusy should be set.
+ */
+ netdev_err(ndev, "tx queue full!\n");
+ return NETDEV_TX_BUSY;
+ }
+
+ ret = txq_submit_skb(skb, ndev);
+ if (ret == -EBUSY)
+ return NETDEV_TX_BUSY;
+
+ if (fep->cur_tx == fep->dirty_tx)
+ netif_stop_queue(ndev);
+
+ return NETDEV_TX_OK;
+}
+
/* Init RX & TX buffer descriptors
*/
static void fec_enet_bd_init(struct net_device *dev)
@@ -770,11 +786,7 @@
if (bdp == fep->cur_tx)
break;
- if (fep->bufdesc_ex)
- index = (struct bufdesc_ex *)bdp -
- (struct bufdesc_ex *)fep->tx_bd_base;
- else
- index = bdp - fep->tx_bd_base;
+ index = fec_enet_get_bd_index(fep->tx_bd_base, bdp, fep);
skb = fep->tx_skbuff[index];
dma_unmap_single(&fep->pdev->dev, bdp->cbd_bufaddr, skb->len,
@@ -921,11 +933,7 @@
pkt_len = bdp->cbd_datlen;
ndev->stats.rx_bytes += pkt_len;
- if (fep->bufdesc_ex)
- index = (struct bufdesc_ex *)bdp -
- (struct bufdesc_ex *)fep->rx_bd_base;
- else
- index = bdp - fep->rx_bd_base;
+ index = fec_enet_get_bd_index(fep->rx_bd_base, bdp, fep);
data = fep->rx_skbuff[index]->data;
dma_sync_single_for_cpu(&fep->pdev->dev, bdp->cbd_bufaddr,
FEC_ENET_RX_FRSIZE, DMA_FROM_DEVICE);
@@ -2061,11 +2069,14 @@
/* Set receive and transmit descriptor base. */
fep->rx_bd_base = cbd_base;
- if (fep->bufdesc_ex)
+ if (fep->bufdesc_ex) {
fep->tx_bd_base = (struct bufdesc *)
(((struct bufdesc_ex *)cbd_base) + fep->rx_ring_size);
- else
+ fep->bufdesc_size = sizeof(struct bufdesc_ex);
+ } else {
fep->tx_bd_base = cbd_base + fep->rx_ring_size;
+ fep->bufdesc_size = sizeof(struct bufdesc);
+ }
/* The FEC Ethernet specific entries in the device structure */
ndev->watchdog_timeo = TX_TIMEOUT;