2 files changed, 272 insertions, 49 deletions

diff --git a/drivers/net/ethernet/cadence/macb.c b/drivers/net/ethernet/cadence/macb.c
index aab7bb22b1d0..f7e21f278e05 100644
--- a/drivers/net/ethernet/cadence/macb.c
+++ b/drivers/net/ethernet/cadence/macb.c
@@ -33,7 +33,6 @@
 #include "macb.h"
 
 #define MACB_RX_BUFFER_SIZE	128
-#define GEM_RX_BUFFER_SIZE	2048
 #define RX_BUFFER_MULTIPLE	64  /* bytes */
 #define RX_RING_SIZE		512 /* must be power of 2 */
 #define RX_RING_BYTES		(sizeof(struct macb_dma_desc) * RX_RING_SIZE)
@@ -530,6 +529,155 @@ static void macb_tx_interrupt(struct macb *bp)
 		netif_wake_queue(bp->dev);
 }
 
+static void gem_rx_refill(struct macb *bp)
+{
+	unsigned int		entry;
+	struct sk_buff		*skb;
+	struct macb_dma_desc	*desc;
+	dma_addr_t		paddr;
+
+	while (CIRC_SPACE(bp->rx_prepared_head, bp->rx_tail, RX_RING_SIZE) > 0) {
+		u32 addr, ctrl;
+
+		entry = macb_rx_ring_wrap(bp->rx_prepared_head);
+		desc = &bp->rx_ring[entry];
+
+		/* Make hw descriptor updates visible to CPU */
+		rmb();
+
+		addr = desc->addr;
+		ctrl = desc->ctrl;
+		bp->rx_prepared_head++;
+
+		if ((addr & MACB_BIT(RX_USED)))
+			continue;
+
+		if (bp->rx_skbuff[entry] == NULL) {
+			/* allocate sk_buff for this free entry in ring */
+			skb = netdev_alloc_skb(bp->dev, bp->rx_buffer_size);
+			if (unlikely(skb == NULL)) {
+				netdev_err(bp->dev,
+					   "Unable to allocate sk_buff\n");
+				break;
+			}
+			bp->rx_skbuff[entry] = skb;
+
+			/* now fill corresponding descriptor entry */
+			paddr = dma_map_single(&bp->pdev->dev, skb->data,
+					       bp->rx_buffer_size, DMA_FROM_DEVICE);
+
+			if (entry == RX_RING_SIZE - 1)
+				paddr |= MACB_BIT(RX_WRAP);
+			bp->rx_ring[entry].addr = paddr;
+			bp->rx_ring[entry].ctrl = 0;
+
+			/* properly align Ethernet header */
+			skb_reserve(skb, NET_IP_ALIGN);
+		}
+	}
+
+	/* Make descriptor updates visible to hardware */
+	wmb();
+
+	netdev_vdbg(bp->dev, "rx ring: prepared head %d, tail %d\n",
+		   bp->rx_prepared_head, bp->rx_tail);
+}
+
+/* Mark DMA descriptors from begin up to and not including end as unused */
+static void discard_partial_frame(struct macb *bp, unsigned int begin,
+				  unsigned int end)
+{
+	unsigned int frag;
+
+	for (frag = begin; frag != end; frag++) {
+		struct macb_dma_desc *desc = macb_rx_desc(bp, frag);
+		desc->addr &= ~MACB_BIT(RX_USED);
+	}
+
+	/* Make descriptor updates visible to hardware */
+	wmb();
+
+	/*
+	 * When this happens, the hardware stats registers for
+	 * whatever caused this is updated, so we don't have to record
+	 * anything.
+	 */
+}
+
+static int gem_rx(struct macb *bp, int budget)
+{
+	unsigned int		len;
+	unsigned int		entry;
+	struct sk_buff		*skb;
+	struct macb_dma_desc	*desc;
+	int			count = 0;
+
+	while (count < budget) {
+		u32 addr, ctrl;
+
+		entry = macb_rx_ring_wrap(bp->rx_tail);
+		desc = &bp->rx_ring[entry];
+
+		/* Make hw descriptor updates visible to CPU */
+		rmb();
+
+		addr = desc->addr;
+		ctrl = desc->ctrl;
+
+		if (!(addr & MACB_BIT(RX_USED)))
+			break;
+
+		desc->addr &= ~MACB_BIT(RX_USED);
+		bp->rx_tail++;
+		count++;
+
+		if (!(ctrl & MACB_BIT(RX_SOF) && ctrl & MACB_BIT(RX_EOF))) {
+			netdev_err(bp->dev,
+				   "not whole frame pointed by descriptor\n");
+			bp->stats.rx_dropped++;
+			break;
+		}
+		skb = bp->rx_skbuff[entry];
+		if (unlikely(!skb)) {
+			netdev_err(bp->dev,
+				   "inconsistent Rx descriptor chain\n");
+			bp->stats.rx_dropped++;
+			break;
+		}
+		/* now everything is ready for receiving packet */
+		bp->rx_skbuff[entry] = NULL;
+		len = MACB_BFEXT(RX_FRMLEN, ctrl);
+
+		netdev_vdbg(bp->dev, "gem_rx %u (len %u)\n", entry, len);
+
+		skb_put(skb, len);
+		addr = MACB_BF(RX_WADDR, MACB_BFEXT(RX_WADDR, addr));
+		dma_unmap_single(&bp->pdev->dev, addr,
+				 len, DMA_FROM_DEVICE);
+
+		skb->protocol = eth_type_trans(skb, bp->dev);
+		skb_checksum_none_assert(skb);
+
+		bp->stats.rx_packets++;
+		bp->stats.rx_bytes += skb->len;
+
+#if defined(DEBUG) && defined(VERBOSE_DEBUG)
+		netdev_vdbg(bp->dev, "received skb of length %u, csum: %08x\n",
+			    skb->len, skb->csum);
+		print_hex_dump(KERN_DEBUG, " mac: ", DUMP_PREFIX_ADDRESS, 16, 1,
+			       skb->mac_header, 16, true);
+		print_hex_dump(KERN_DEBUG, "data: ", DUMP_PREFIX_ADDRESS, 16, 1,
+			       skb->data, 32, true);
+#endif
+
+		netif_receive_skb(skb);
+	}
+
+	gem_rx_refill(bp);
+
+	return count;
+}
+
 static int macb_rx_frame(struct macb *bp, unsigned int first_frag,
 			 unsigned int last_frag)
 {
@@ -608,27 +756,6 @@ static int macb_rx_frame(struct macb *bp, unsigned int first_frag,
 	return 0;
 }
 
-/* Mark DMA descriptors from begin up to and not including end as unused */
-static void discard_partial_frame(struct macb *bp, unsigned int begin,
-				  unsigned int end)
-{
-	unsigned int frag;
-
-	for (frag = begin; frag != end; frag++) {
-		struct macb_dma_desc *desc = macb_rx_desc(bp, frag);
-		desc->addr &= ~MACB_BIT(RX_USED);
-	}
-
-	/* Make descriptor updates visible to hardware */
-	wmb();
-
-	/*
-	 * When this happens, the hardware stats registers for
-	 * whatever caused this is updated, so we don't have to record
-	 * anything.
-	 */
-}
-
 static int macb_rx(struct macb *bp, int budget)
 {
 	int received = 0;
@@ -689,7 +816,7 @@ static int macb_poll(struct napi_struct *napi, int budget)
 	netdev_vdbg(bp->dev, "poll: status = %08lx, budget = %d\n",
 		   (unsigned long)status, budget);
 
-	work_done = macb_rx(bp, budget);
+	work_done = bp->macbgem_ops.mog_rx(bp, budget);
 	if (work_done < budget) {
 		napi_complete(napi);
 
@@ -872,29 +999,63 @@ static int macb_start_xmit(struct sk_buff *skb, struct net_device *dev)
 	return NETDEV_TX_OK;
 }
 
-static void macb_init_rx_buffer_size(struct macb *bp)
+static void macb_init_rx_buffer_size(struct macb *bp, size_t size)
 {
 	if (!macb_is_gem(bp)) {
 		bp->rx_buffer_size = MACB_RX_BUFFER_SIZE;
 	} else {
-		bp->rx_buffer_size = GEM_RX_BUFFER_SIZE;
+		bp->rx_buffer_size = size;
 
-		if (bp->rx_buffer_size > PAGE_SIZE) {
-			netdev_warn(bp->dev,
-				    "RX buffer cannot be bigger than PAGE_SIZE, shrinking\n");
-			bp->rx_buffer_size = PAGE_SIZE;
-		}
 		if (bp->rx_buffer_size % RX_BUFFER_MULTIPLE) {
-			netdev_warn(bp->dev,
-				    "RX buffer must be multiple of %d bytes, shrinking\n",
+			netdev_dbg(bp->dev,
+				    "RX buffer must be multiple of %d bytes, expanding\n",
 				    RX_BUFFER_MULTIPLE);
 			bp->rx_buffer_size =
-				rounddown(bp->rx_buffer_size, RX_BUFFER_MULTIPLE);
+				roundup(bp->rx_buffer_size, RX_BUFFER_MULTIPLE);
 		}
-		bp->rx_buffer_size = max(RX_BUFFER_MULTIPLE, GEM_RX_BUFFER_SIZE);
 	}
+
+	netdev_dbg(bp->dev, "mtu [%u] rx_buffer_size [%Zu]\n",
+		   bp->dev->mtu, bp->rx_buffer_size);
 }
 
+static void gem_free_rx_buffers(struct macb *bp)
+{
+	struct sk_buff		*skb;
+	struct macb_dma_desc	*desc;
+	dma_addr_t		addr;
+	int i;
+
+	if (!bp->rx_skbuff)
+		return;
+
+	for (i = 0; i < RX_RING_SIZE; i++) {
+		skb = bp->rx_skbuff[i];
+
+		if (skb == NULL)
+			continue;
+
+		desc = &bp->rx_ring[i];
+		addr = MACB_BF(RX_WADDR, MACB_BFEXT(RX_WADDR, desc->addr));
+		dma_unmap_single(&bp->pdev->dev, addr, skb->len,
+				 DMA_FROM_DEVICE);
+		dev_kfree_skb_any(skb);
+		skb = NULL;
+	}
+
+	kfree(bp->rx_skbuff);
+	bp->rx_skbuff = NULL;
+}
+
+static void macb_free_rx_buffers(struct macb *bp)
+{
+	if (bp->rx_buffers) {
+		dma_free_coherent(&bp->pdev->dev,
+				  RX_RING_SIZE * bp->rx_buffer_size,
+				  bp->rx_buffers, bp->rx_buffers_dma);
+		bp->rx_buffers = NULL;
+	}
+}
 
 static void macb_free_consistent(struct macb *bp)
 {
@@ -902,6 +1063,7 @@ static void macb_free_consistent(struct macb *bp)
 		kfree(bp->tx_skb);
 		bp->tx_skb = NULL;
 	}
+	bp->macbgem_ops.mog_free_rx_buffers(bp);
 	if (bp->rx_ring) {
 		dma_free_coherent(&bp->pdev->dev, RX_RING_BYTES,
 				  bp->rx_ring, bp->rx_ring_dma);
@@ -912,12 +1074,37 @@ static void macb_free_consistent(struct macb *bp)
 				  bp->tx_ring, bp->tx_ring_dma);
 		bp->tx_ring = NULL;
 	}
-	if (bp->rx_buffers) {
-		dma_free_coherent(&bp->pdev->dev,
-				  RX_RING_SIZE * bp->rx_buffer_size,
-				  bp->rx_buffers, bp->rx_buffers_dma);
-		bp->rx_buffers = NULL;
-	}
+}
+
+static int gem_alloc_rx_buffers(struct macb *bp)
+{
+	int size;
+
+	size = RX_RING_SIZE * sizeof(struct sk_buff *);
+	bp->rx_skbuff = kzalloc(size, GFP_KERNEL);
+	if (!bp->rx_skbuff)
+		return -ENOMEM;
+	else
+		netdev_dbg(bp->dev,
+			   "Allocated %d RX struct sk_buff entries at %p\n",
+			   RX_RING_SIZE, bp->rx_skbuff);
+	return 0;
+}
+
+static int macb_alloc_rx_buffers(struct macb *bp)
+{
+	int size;
+
+	size = RX_RING_SIZE * bp->rx_buffer_size;
+	bp->rx_buffers = dma_alloc_coherent(&bp->pdev->dev, size,
+					    &bp->rx_buffers_dma, GFP_KERNEL);
+	if (!bp->rx_buffers)
+		return -ENOMEM;
+	else
+		netdev_dbg(bp->dev,
+			   "Allocated RX buffers of %d bytes at %08lx (mapped %p)\n",
+			   size, (unsigned long)bp->rx_buffers_dma, bp->rx_buffers);
+	return 0;
 }
 
 static int macb_alloc_consistent(struct macb *bp)
@@ -947,14 +1134,8 @@ static int macb_alloc_consistent(struct macb *bp)
 		   "Allocated TX ring of %d bytes at %08lx (mapped %p)\n",
 		   size, (unsigned long)bp->tx_ring_dma, bp->tx_ring);
 
-	size = RX_RING_SIZE * bp->rx_buffer_size;
-	bp->rx_buffers = dma_alloc_coherent(&bp->pdev->dev, size,
-					    &bp->rx_buffers_dma, GFP_KERNEL);
-	if (!bp->rx_buffers)
+	if (bp->macbgem_ops.mog_alloc_rx_buffers(bp))
 		goto out_err;
-	netdev_dbg(bp->dev,
-		   "Allocated RX buffers of %d bytes at %08lx (mapped %p)\n",
-		   size, (unsigned long)bp->rx_buffers_dma, bp->rx_buffers);
 
 	return 0;
 
@@ -963,6 +1144,21 @@ out_err:
 	return -ENOMEM;
 }
 
+static void gem_init_rings(struct macb *bp)
+{
+	int i;
+
+	for (i = 0; i < TX_RING_SIZE; i++) {
+		bp->tx_ring[i].addr = 0;
+		bp->tx_ring[i].ctrl = MACB_BIT(TX_USED);
+	}
+	bp->tx_ring[TX_RING_SIZE - 1].ctrl |= MACB_BIT(TX_WRAP);
+
+	bp->rx_tail = bp->rx_prepared_head = bp->tx_head = bp->tx_tail = 0;
+
+	gem_rx_refill(bp);
+}
+
 static void macb_init_rings(struct macb *bp)
 {
 	int i;
@@ -1259,6 +1455,7 @@ EXPORT_SYMBOL_GPL(macb_set_rx_mode);
 static int macb_open(struct net_device *dev)
 {
 	struct macb *bp = netdev_priv(dev);
+	size_t bufsz = dev->mtu + ETH_HLEN + ETH_FCS_LEN + NET_IP_ALIGN;
 	int err;
 
 	netdev_dbg(bp->dev, "open\n");
@@ -1271,7 +1468,7 @@ static int macb_open(struct net_device *dev)
 		return -EAGAIN;
 
 	/* RX buffers initialization */
-	macb_init_rx_buffer_size(bp);
+	macb_init_rx_buffer_size(bp, bufsz);
 
 	err = macb_alloc_consistent(bp);
 	if (err) {
@@ -1282,7 +1479,7 @@ static int macb_open(struct net_device *dev)
 
 	napi_enable(&bp->napi);
 
-	macb_init_rings(bp);
+	bp->macbgem_ops.mog_init_rings(bp);
 	macb_init_hw(bp);
 
 	/* schedule a link state check */
@@ -1601,6 +1798,19 @@ static int __init macb_probe(struct platform_device *pdev)
 
 	dev->base_addr = regs->start;
 
+	/* setup appropriated routines according to adapter type */
+	if (macb_is_gem(bp)) {
+		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->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 MII management clock divider */
 	config = macb_mdc_clk_div(bp);
 	config |= macb_dbw(bp);
diff --git a/drivers/net/ethernet/cadence/macb.h b/drivers/net/ethernet/cadence/macb.h
index 9b5e19f8b61d..f4076155bed7 100644
--- a/drivers/net/ethernet/cadence/macb.h
+++ b/drivers/net/ethernet/cadence/macb.h
@@ -545,11 +545,22 @@ struct gem_stats {
 	u32	rx_udp_checksum_errors;
 };
 
+struct macb;
+
+struct macb_or_gem_ops {
+	int	(*mog_alloc_rx_buffers)(struct macb *bp);
+	void	(*mog_free_rx_buffers)(struct macb *bp);
+	void	(*mog_init_rings)(struct macb *bp);
+	int	(*mog_rx)(struct macb *bp, int budget);
+};
+
 struct macb {
 	void __iomem		*regs;
 
 	unsigned int		rx_tail;
+	unsigned int		rx_prepared_head;
 	struct macb_dma_desc	*rx_ring;
+	struct sk_buff		**rx_skbuff;
 	void			*rx_buffers;
 	size_t			rx_buffer_size;
 
@@ -574,6 +585,8 @@ struct macb {
 	dma_addr_t		tx_ring_dma;
 	dma_addr_t		rx_buffers_dma;
 
+	struct macb_or_gem_ops	macbgem_ops;
+
 	struct mii_bus		*mii_bus;
 	struct phy_device	*phy_dev;
 	unsigned int 		link;