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path: root/drivers/net/ethernet/cadence/macb.c
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Diffstat (limited to 'drivers/net/ethernet/cadence/macb.c')
-rw-r--r--drivers/net/ethernet/cadence/macb.c419
1 files changed, 349 insertions, 70 deletions
diff --git a/drivers/net/ethernet/cadence/macb.c b/drivers/net/ethernet/cadence/macb.c
index e9daa072ebb4..ca5d7798b265 100644
--- a/drivers/net/ethernet/cadence/macb.c
+++ b/drivers/net/ethernet/cadence/macb.c
@@ -52,6 +52,9 @@
| MACB_BIT(TXERR))
#define MACB_TX_INT_FLAGS (MACB_TX_ERR_FLAGS | MACB_BIT(TCOMP))
+#define MACB_MAX_TX_LEN ((unsigned int)((1 << MACB_TX_FRMLEN_SIZE) - 1))
+#define GEM_MAX_TX_LEN ((unsigned int)((1 << GEM_TX_FRMLEN_SIZE) - 1))
+
/*
* Graceful stop timeouts in us. We should allow up to
* 1 frame time (10 Mbits/s, full-duplex, ignoring collisions)
@@ -264,7 +267,8 @@ static void macb_handle_link_change(struct net_device *dev)
reg |= MACB_BIT(FD);
if (phydev->speed == SPEED_100)
reg |= MACB_BIT(SPD);
- if (phydev->speed == SPEED_1000)
+ if (phydev->speed == SPEED_1000 &&
+ bp->caps & MACB_CAPS_GIGABIT_MODE_AVAILABLE)
reg |= GEM_BIT(GBE);
macb_or_gem_writel(bp, NCFGR, reg);
@@ -337,7 +341,7 @@ static int macb_mii_probe(struct net_device *dev)
}
/* mask with MAC supported features */
- if (macb_is_gem(bp))
+ if (macb_is_gem(bp) && bp->caps & MACB_CAPS_GIGABIT_MODE_AVAILABLE)
phydev->supported &= PHY_GBIT_FEATURES;
else
phydev->supported &= PHY_BASIC_FEATURES;
@@ -467,6 +471,24 @@ static int macb_halt_tx(struct macb *bp)
return -ETIMEDOUT;
}
+static void macb_tx_unmap(struct macb *bp, struct macb_tx_skb *tx_skb)
+{
+ if (tx_skb->mapping) {
+ if (tx_skb->mapped_as_page)
+ dma_unmap_page(&bp->pdev->dev, tx_skb->mapping,
+ tx_skb->size, DMA_TO_DEVICE);
+ else
+ dma_unmap_single(&bp->pdev->dev, tx_skb->mapping,
+ tx_skb->size, DMA_TO_DEVICE);
+ tx_skb->mapping = 0;
+ }
+
+ if (tx_skb->skb) {
+ dev_kfree_skb_any(tx_skb->skb);
+ tx_skb->skb = NULL;
+ }
+}
+
static void macb_tx_error_task(struct work_struct *work)
{
struct macb *bp = container_of(work, struct macb, tx_error_task);
@@ -504,10 +526,23 @@ static void macb_tx_error_task(struct work_struct *work)
skb = tx_skb->skb;
if (ctrl & MACB_BIT(TX_USED)) {
- netdev_vdbg(bp->dev, "txerr skb %u (data %p) TX complete\n",
- macb_tx_ring_wrap(tail), skb->data);
- bp->stats.tx_packets++;
- bp->stats.tx_bytes += skb->len;
+ /* skb is set for the last buffer of the frame */
+ while (!skb) {
+ macb_tx_unmap(bp, tx_skb);
+ tail++;
+ tx_skb = macb_tx_skb(bp, tail);
+ skb = tx_skb->skb;
+ }
+
+ /* ctrl still refers to the first buffer descriptor
+ * since it's the only one written back by the hardware
+ */
+ if (!(ctrl & MACB_BIT(TX_BUF_EXHAUSTED))) {
+ netdev_vdbg(bp->dev, "txerr skb %u (data %p) TX complete\n",
+ macb_tx_ring_wrap(tail), skb->data);
+ bp->stats.tx_packets++;
+ bp->stats.tx_bytes += skb->len;
+ }
} else {
/*
* "Buffers exhausted mid-frame" errors may only happen
@@ -521,10 +556,7 @@ static void macb_tx_error_task(struct work_struct *work)
desc->ctrl = ctrl | MACB_BIT(TX_USED);
}
- dma_unmap_single(&bp->pdev->dev, tx_skb->mapping, skb->len,
- DMA_TO_DEVICE);
- tx_skb->skb = NULL;
- dev_kfree_skb(skb);
+ macb_tx_unmap(bp, tx_skb);
}
/* Make descriptor updates visible to hardware */
@@ -572,20 +604,35 @@ static void macb_tx_interrupt(struct macb *bp)
ctrl = desc->ctrl;
+ /* TX_USED bit is only set by hardware on the very first buffer
+ * descriptor of the transmitted frame.
+ */
if (!(ctrl & MACB_BIT(TX_USED)))
break;
- tx_skb = macb_tx_skb(bp, tail);
- skb = tx_skb->skb;
+ /* Process all buffers of the current transmitted frame */
+ for (;; tail++) {
+ tx_skb = macb_tx_skb(bp, tail);
+ skb = tx_skb->skb;
+
+ /* First, update TX stats if needed */
+ if (skb) {
+ netdev_vdbg(bp->dev, "skb %u (data %p) TX complete\n",
+ macb_tx_ring_wrap(tail), skb->data);
+ bp->stats.tx_packets++;
+ bp->stats.tx_bytes += skb->len;
+ }
- netdev_vdbg(bp->dev, "skb %u (data %p) TX complete\n",
- macb_tx_ring_wrap(tail), skb->data);
- dma_unmap_single(&bp->pdev->dev, tx_skb->mapping, skb->len,
- DMA_TO_DEVICE);
- bp->stats.tx_packets++;
- bp->stats.tx_bytes += skb->len;
- tx_skb->skb = NULL;
- dev_kfree_skb_irq(skb);
+ /* Now we can safely release resources */
+ macb_tx_unmap(bp, tx_skb);
+
+ /* skb is set only for the last buffer of the frame.
+ * WARNING: at this point skb has been freed by
+ * macb_tx_unmap().
+ */
+ if (skb)
+ break;
+ }
}
bp->tx_tail = tail;
@@ -718,6 +765,10 @@ static int gem_rx(struct macb *bp, int budget)
skb->protocol = eth_type_trans(skb, bp->dev);
skb_checksum_none_assert(skb);
+ if (bp->dev->features & NETIF_F_RXCSUM &&
+ !(bp->dev->flags & IFF_PROMISC) &&
+ GEM_BFEXT(RX_CSUM, ctrl) & GEM_RX_CSUM_CHECKED_MASK)
+ skb->ip_summed = CHECKSUM_UNNECESSARY;
bp->stats.rx_packets++;
bp->stats.rx_bytes += skb->len;
@@ -1001,15 +1052,145 @@ static void macb_poll_controller(struct net_device *dev)
}
#endif
-static int macb_start_xmit(struct sk_buff *skb, struct net_device *dev)
+static inline unsigned int macb_count_tx_descriptors(struct macb *bp,
+ unsigned int len)
+{
+ return (len + bp->max_tx_length - 1) / bp->max_tx_length;
+}
+
+static unsigned int macb_tx_map(struct macb *bp,
+ struct sk_buff *skb)
{
- struct macb *bp = netdev_priv(dev);
dma_addr_t mapping;
- unsigned int len, entry;
+ unsigned int len, entry, i, tx_head = bp->tx_head;
+ struct macb_tx_skb *tx_skb = NULL;
struct macb_dma_desc *desc;
- struct macb_tx_skb *tx_skb;
+ unsigned int offset, size, count = 0;
+ unsigned int f, nr_frags = skb_shinfo(skb)->nr_frags;
+ unsigned int eof = 1;
u32 ctrl;
+
+ /* First, map non-paged data */
+ len = skb_headlen(skb);
+ offset = 0;
+ while (len) {
+ size = min(len, bp->max_tx_length);
+ entry = macb_tx_ring_wrap(tx_head);
+ tx_skb = &bp->tx_skb[entry];
+
+ mapping = dma_map_single(&bp->pdev->dev,
+ skb->data + offset,
+ size, DMA_TO_DEVICE);
+ if (dma_mapping_error(&bp->pdev->dev, mapping))
+ goto dma_error;
+
+ /* Save info to properly release resources */
+ tx_skb->skb = NULL;
+ tx_skb->mapping = mapping;
+ tx_skb->size = size;
+ tx_skb->mapped_as_page = false;
+
+ len -= size;
+ offset += size;
+ count++;
+ tx_head++;
+ }
+
+ /* Then, map paged data from fragments */
+ for (f = 0; f < nr_frags; f++) {
+ const skb_frag_t *frag = &skb_shinfo(skb)->frags[f];
+
+ len = skb_frag_size(frag);
+ offset = 0;
+ while (len) {
+ size = min(len, bp->max_tx_length);
+ entry = macb_tx_ring_wrap(tx_head);
+ tx_skb = &bp->tx_skb[entry];
+
+ mapping = skb_frag_dma_map(&bp->pdev->dev, frag,
+ offset, size, DMA_TO_DEVICE);
+ if (dma_mapping_error(&bp->pdev->dev, mapping))
+ goto dma_error;
+
+ /* Save info to properly release resources */
+ tx_skb->skb = NULL;
+ tx_skb->mapping = mapping;
+ tx_skb->size = size;
+ tx_skb->mapped_as_page = true;
+
+ len -= size;
+ offset += size;
+ count++;
+ tx_head++;
+ }
+ }
+
+ /* Should never happen */
+ if (unlikely(tx_skb == NULL)) {
+ netdev_err(bp->dev, "BUG! empty skb!\n");
+ return 0;
+ }
+
+ /* This is the last buffer of the frame: save socket buffer */
+ tx_skb->skb = skb;
+
+ /* Update TX ring: update buffer descriptors in reverse order
+ * to avoid race condition
+ */
+
+ /* Set 'TX_USED' bit in buffer descriptor at tx_head position
+ * to set the end of TX queue
+ */
+ i = tx_head;
+ entry = macb_tx_ring_wrap(i);
+ ctrl = MACB_BIT(TX_USED);
+ desc = &bp->tx_ring[entry];
+ desc->ctrl = ctrl;
+
+ do {
+ i--;
+ entry = macb_tx_ring_wrap(i);
+ tx_skb = &bp->tx_skb[entry];
+ desc = &bp->tx_ring[entry];
+
+ ctrl = (u32)tx_skb->size;
+ if (eof) {
+ ctrl |= MACB_BIT(TX_LAST);
+ eof = 0;
+ }
+ if (unlikely(entry == (TX_RING_SIZE - 1)))
+ ctrl |= MACB_BIT(TX_WRAP);
+
+ /* Set TX buffer descriptor */
+ desc->addr = tx_skb->mapping;
+ /* desc->addr must be visible to hardware before clearing
+ * 'TX_USED' bit in desc->ctrl.
+ */
+ wmb();
+ desc->ctrl = ctrl;
+ } while (i != bp->tx_head);
+
+ bp->tx_head = tx_head;
+
+ return count;
+
+dma_error:
+ netdev_err(bp->dev, "TX DMA map failed\n");
+
+ for (i = bp->tx_head; i != tx_head; i++) {
+ tx_skb = macb_tx_skb(bp, i);
+
+ macb_tx_unmap(bp, tx_skb);
+ }
+
+ return 0;
+}
+
+static int macb_start_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+ struct macb *bp = netdev_priv(dev);
unsigned long flags;
+ unsigned int count, nr_frags, frag_size, f;
#if defined(DEBUG) && defined(VERBOSE_DEBUG)
netdev_vdbg(bp->dev,
@@ -1020,44 +1201,34 @@ static int macb_start_xmit(struct sk_buff *skb, struct net_device *dev)
skb->data, 16, true);
#endif
- len = skb->len;
+ /* Count how many TX buffer descriptors are needed to send this
+ * socket buffer: skb fragments of jumbo frames may need to be
+ * splitted into many buffer descriptors.
+ */
+ count = macb_count_tx_descriptors(bp, skb_headlen(skb));
+ nr_frags = skb_shinfo(skb)->nr_frags;
+ for (f = 0; f < nr_frags; f++) {
+ frag_size = skb_frag_size(&skb_shinfo(skb)->frags[f]);
+ count += macb_count_tx_descriptors(bp, frag_size);
+ }
+
spin_lock_irqsave(&bp->lock, flags);
/* This is a hard error, log it. */
- if (CIRC_SPACE(bp->tx_head, bp->tx_tail, TX_RING_SIZE) < 1) {
+ if (CIRC_SPACE(bp->tx_head, bp->tx_tail, TX_RING_SIZE) < count) {
netif_stop_queue(dev);
spin_unlock_irqrestore(&bp->lock, flags);
- netdev_err(bp->dev, "BUG! Tx Ring full when queue awake!\n");
netdev_dbg(bp->dev, "tx_head = %u, tx_tail = %u\n",
bp->tx_head, bp->tx_tail);
return NETDEV_TX_BUSY;
}
- entry = macb_tx_ring_wrap(bp->tx_head);
- netdev_vdbg(bp->dev, "Allocated ring entry %u\n", entry);
- mapping = dma_map_single(&bp->pdev->dev, skb->data,
- len, DMA_TO_DEVICE);
- if (dma_mapping_error(&bp->pdev->dev, mapping)) {
+ /* Map socket buffer for DMA transfer */
+ if (!macb_tx_map(bp, skb)) {
dev_kfree_skb_any(skb);
goto unlock;
}
- bp->tx_head++;
- tx_skb = &bp->tx_skb[entry];
- tx_skb->skb = skb;
- tx_skb->mapping = mapping;
- netdev_vdbg(bp->dev, "Mapped skb data %p to DMA addr %08lx\n",
- skb->data, (unsigned long)mapping);
-
- ctrl = MACB_BF(TX_FRMLEN, len);
- ctrl |= MACB_BIT(TX_LAST);
- if (entry == (TX_RING_SIZE - 1))
- ctrl |= MACB_BIT(TX_WRAP);
-
- desc = &bp->tx_ring[entry];
- desc->addr = mapping;
- desc->ctrl = ctrl;
-
/* Make newly initialized descriptor visible to hardware */
wmb();
@@ -1342,7 +1513,7 @@ static u32 macb_dbw(struct macb *bp)
/*
* Configure the receive DMA engine
* - use the correct receive buffer size
- * - set the possibility to use INCR16 bursts
+ * - set best burst length for DMA operations
* (if not supported by FIFO, it will fallback to default)
* - set both rx/tx packet buffers to full memory size
* These are configurable parameters for GEM.
@@ -1354,24 +1525,20 @@ static void macb_configure_dma(struct macb *bp)
if (macb_is_gem(bp)) {
dmacfg = gem_readl(bp, DMACFG) & ~GEM_BF(RXBS, -1L);
dmacfg |= GEM_BF(RXBS, bp->rx_buffer_size / RX_BUFFER_MULTIPLE);
- dmacfg |= GEM_BF(FBLDO, 16);
+ if (bp->dma_burst_length)
+ dmacfg = GEM_BFINS(FBLDO, bp->dma_burst_length, dmacfg);
dmacfg |= GEM_BIT(TXPBMS) | GEM_BF(RXBMS, -1L);
dmacfg &= ~GEM_BIT(ENDIA);
+ if (bp->dev->features & NETIF_F_HW_CSUM)
+ dmacfg |= GEM_BIT(TXCOEN);
+ else
+ dmacfg &= ~GEM_BIT(TXCOEN);
+ netdev_dbg(bp->dev, "Cadence configure DMA with 0x%08x\n",
+ dmacfg);
gem_writel(bp, DMACFG, dmacfg);
}
}
-/*
- * Configure peripheral capacities according to integration options used
- */
-static void macb_configure_caps(struct macb *bp)
-{
- if (macb_is_gem(bp)) {
- if (GEM_BFEXT(IRQCOR, gem_readl(bp, DCFG1)) == 0)
- bp->caps |= MACB_CAPS_ISR_CLEAR_ON_WRITE;
- }
-}
-
static void macb_init_hw(struct macb *bp)
{
u32 config;
@@ -1386,6 +1553,8 @@ static void macb_init_hw(struct macb *bp)
config |= MACB_BIT(BIG); /* Receive oversized frames */
if (bp->dev->flags & IFF_PROMISC)
config |= MACB_BIT(CAF); /* Copy All Frames */
+ else if (macb_is_gem(bp) && bp->dev->features & NETIF_F_RXCSUM)
+ config |= GEM_BIT(RXCOEN);
if (!(bp->dev->flags & IFF_BROADCAST))
config |= MACB_BIT(NBC); /* No BroadCast */
config |= macb_dbw(bp);
@@ -1394,7 +1563,6 @@ static void macb_init_hw(struct macb *bp)
bp->duplex = DUPLEX_HALF;
macb_configure_dma(bp);
- macb_configure_caps(bp);
/* Initialize TX and RX buffers */
macb_writel(bp, RBQP, bp->rx_ring_dma);
@@ -1500,13 +1668,22 @@ void macb_set_rx_mode(struct net_device *dev)
cfg = macb_readl(bp, NCFGR);
- if (dev->flags & IFF_PROMISC)
+ if (dev->flags & IFF_PROMISC) {
/* Enable promiscuous mode */
cfg |= MACB_BIT(CAF);
- else if (dev->flags & (~IFF_PROMISC))
- /* Disable promiscuous mode */
+
+ /* Disable RX checksum offload */
+ if (macb_is_gem(bp))
+ cfg &= ~GEM_BIT(RXCOEN);
+ } else {
+ /* Disable promiscuous mode */
cfg &= ~MACB_BIT(CAF);
+ /* Enable RX checksum offload only if requested */
+ if (macb_is_gem(bp) && dev->features & NETIF_F_RXCSUM)
+ cfg |= GEM_BIT(RXCOEN);
+ }
+
if (dev->flags & IFF_ALLMULTI) {
/* Enable all multicast mode */
macb_or_gem_writel(bp, HRB, -1);
@@ -1767,6 +1944,40 @@ int macb_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
}
EXPORT_SYMBOL_GPL(macb_ioctl);
+static int macb_set_features(struct net_device *netdev,
+ netdev_features_t features)
+{
+ struct macb *bp = netdev_priv(netdev);
+ netdev_features_t changed = features ^ netdev->features;
+
+ /* TX checksum offload */
+ if ((changed & NETIF_F_HW_CSUM) && macb_is_gem(bp)) {
+ u32 dmacfg;
+
+ dmacfg = gem_readl(bp, DMACFG);
+ if (features & NETIF_F_HW_CSUM)
+ dmacfg |= GEM_BIT(TXCOEN);
+ else
+ dmacfg &= ~GEM_BIT(TXCOEN);
+ gem_writel(bp, DMACFG, dmacfg);
+ }
+
+ /* RX checksum offload */
+ if ((changed & NETIF_F_RXCSUM) && macb_is_gem(bp)) {
+ u32 netcfg;
+
+ netcfg = gem_readl(bp, NCFGR);
+ if (features & NETIF_F_RXCSUM &&
+ !(netdev->flags & IFF_PROMISC))
+ netcfg |= GEM_BIT(RXCOEN);
+ else
+ netcfg &= ~GEM_BIT(RXCOEN);
+ gem_writel(bp, NCFGR, netcfg);
+ }
+
+ return 0;
+}
+
static const struct net_device_ops macb_netdev_ops = {
.ndo_open = macb_open,
.ndo_stop = macb_close,
@@ -1780,20 +1991,77 @@ static const struct net_device_ops macb_netdev_ops = {
#ifdef CONFIG_NET_POLL_CONTROLLER
.ndo_poll_controller = macb_poll_controller,
#endif
+ .ndo_set_features = macb_set_features,
};
#if defined(CONFIG_OF)
+static struct macb_config pc302gem_config = {
+ .caps = MACB_CAPS_SG_DISABLED | MACB_CAPS_GIGABIT_MODE_AVAILABLE,
+ .dma_burst_length = 16,
+};
+
+static struct macb_config sama5d3_config = {
+ .caps = MACB_CAPS_SG_DISABLED | MACB_CAPS_GIGABIT_MODE_AVAILABLE,
+ .dma_burst_length = 16,
+};
+
+static struct macb_config sama5d4_config = {
+ .caps = 0,
+ .dma_burst_length = 4,
+};
+
static const struct of_device_id macb_dt_ids[] = {
{ .compatible = "cdns,at32ap7000-macb" },
{ .compatible = "cdns,at91sam9260-macb" },
{ .compatible = "cdns,macb" },
- { .compatible = "cdns,pc302-gem" },
- { .compatible = "cdns,gem" },
+ { .compatible = "cdns,pc302-gem", .data = &pc302gem_config },
+ { .compatible = "cdns,gem", .data = &pc302gem_config },
+ { .compatible = "atmel,sama5d3-gem", .data = &sama5d3_config },
+ { .compatible = "atmel,sama5d4-gem", .data = &sama5d4_config },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, macb_dt_ids);
#endif
+/*
+ * Configure peripheral capacities according to device tree
+ * and integration options used
+ */
+static void macb_configure_caps(struct macb *bp)
+{
+ u32 dcfg;
+ const struct of_device_id *match;
+ const struct macb_config *config;
+
+ if (bp->pdev->dev.of_node) {
+ match = of_match_node(macb_dt_ids, bp->pdev->dev.of_node);
+ if (match && match->data) {
+ config = (const struct macb_config *)match->data;
+
+ bp->caps = config->caps;
+ /*
+ * As we have access to the matching node, configure
+ * DMA burst length as well
+ */
+ bp->dma_burst_length = config->dma_burst_length;
+ }
+ }
+
+ if (MACB_BFEXT(IDNUM, macb_readl(bp, MID)) == 0x2)
+ bp->caps |= MACB_CAPS_MACB_IS_GEM;
+
+ if (macb_is_gem(bp)) {
+ dcfg = gem_readl(bp, DCFG1);
+ if (GEM_BFEXT(IRQCOR, dcfg) == 0)
+ bp->caps |= MACB_CAPS_ISR_CLEAR_ON_WRITE;
+ dcfg = gem_readl(bp, DCFG2);
+ if ((dcfg & (GEM_BIT(RX_PKT_BUFF) | GEM_BIT(TX_PKT_BUFF))) == 0)
+ bp->caps |= MACB_CAPS_FIFO_MODE;
+ }
+
+ netdev_dbg(bp->dev, "Cadence caps 0x%08x\n", bp->caps);
+}
+
static int __init macb_probe(struct platform_device *pdev)
{
struct macb_platform_data *pdata;
@@ -1828,9 +2096,6 @@ static int __init macb_probe(struct platform_device *pdev)
SET_NETDEV_DEV(dev, &pdev->dev);
- /* TODO: Actually, we have some interesting features... */
- dev->features |= 0;
-
bp = netdev_priv(dev);
bp->pdev = pdev;
bp->dev = dev;
@@ -1897,19 +2162,33 @@ static int __init macb_probe(struct platform_device *pdev)
dev->base_addr = regs->start;
+ /* setup capacities */
+ macb_configure_caps(bp);
+
/* setup appropriated routines according to adapter type */
if (macb_is_gem(bp)) {
+ bp->max_tx_length = GEM_MAX_TX_LEN;
bp->macbgem_ops.mog_alloc_rx_buffers = gem_alloc_rx_buffers;
bp->macbgem_ops.mog_free_rx_buffers = gem_free_rx_buffers;
bp->macbgem_ops.mog_init_rings = gem_init_rings;
bp->macbgem_ops.mog_rx = gem_rx;
} else {
+ bp->max_tx_length = MACB_MAX_TX_LEN;
bp->macbgem_ops.mog_alloc_rx_buffers = macb_alloc_rx_buffers;
bp->macbgem_ops.mog_free_rx_buffers = macb_free_rx_buffers;
bp->macbgem_ops.mog_init_rings = macb_init_rings;
bp->macbgem_ops.mog_rx = macb_rx;
}
+ /* Set features */
+ dev->hw_features = NETIF_F_SG;
+ /* Checksum offload is only available on gem with packet buffer */
+ if (macb_is_gem(bp) && !(bp->caps & MACB_CAPS_FIFO_MODE))
+ dev->hw_features |= NETIF_F_HW_CSUM | NETIF_F_RXCSUM;
+ if (bp->caps & MACB_CAPS_SG_DISABLED)
+ dev->hw_features &= ~NETIF_F_SG;
+ dev->features = dev->hw_features;
+
/* Set MII management clock divider */
config = macb_mdc_clk_div(bp);
config |= macb_dbw(bp);