branch Attitude Adjustment

git-svn-id: svn://svn.openwrt.org/openwrt/branches/attitude_adjustment@33625 3c298f89-4303-0410-b956-a3cf2f4a3e73

3 files changed, 1195 insertions, 0 deletions

diff --git a/target/linux/mcs814x/files-3.3/drivers/net/ethernet/mcs8140/Kconfig b/target/linux/mcs814x/files-3.3/drivers/net/ethernet/mcs8140/Kconfig
new file mode 100644
index 000000000..8fa38a409
--- /dev/null
+++ b/target/linux/mcs814x/files-3.3/drivers/net/ethernet/mcs8140/Kconfig
@@ -0,0 +1,4 @@
+config  NUPORT_ETHERNET_DRIVER
+	tristate "MCS8140 Ethernet driver"
+	depends on ETHERNET && ARCH_MCS814X
+          help
diff --git a/target/linux/mcs814x/files-3.3/drivers/net/ethernet/mcs8140/Makefile b/target/linux/mcs814x/files-3.3/drivers/net/ethernet/mcs8140/Makefile
new file mode 100644
index 000000000..9719c51b7
--- /dev/null
+++ b/target/linux/mcs814x/files-3.3/drivers/net/ethernet/mcs8140/Makefile
@@ -0,0 +1,3 @@
+obj-$(CONFIG_NUPORT_ETHERNET_DRIVER)   += mcs8140.o
+
+mcs8140-objs  := nuport_mac.o 
diff --git a/target/linux/mcs814x/files-3.3/drivers/net/ethernet/mcs8140/nuport_mac.c b/target/linux/mcs814x/files-3.3/drivers/net/ethernet/mcs8140/nuport_mac.c
new file mode 100644
index 000000000..fe95ea7f7
--- /dev/null
+++ b/target/linux/mcs814x/files-3.3/drivers/net/ethernet/mcs8140/nuport_mac.c
@@ -0,0 +1,1188 @@
+/*
+ * Moschip MCS8140 Ethernet MAC driver
+ *
+ * Copyright (C) 2003, Moschip Semiconductors
+ * Copyright (C) 2012, Florian Fainelli <florian@openwrt.org>
+ *
+ * Licensed under GPLv2
+ */
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/delay.h>
+#include <linux/ethtool.h>
+#include <linux/mii.h>
+#include <linux/io.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/of.h>
+#include <linux/irq.h>
+#include <linux/err.h>
+#include <linux/phy.h>
+#include <linux/clk.h>
+#include <linux/dma-mapping.h>
+
+#include <asm/unaligned.h>
+#include <asm/sizes.h>
+
+/* Hardware registers */
+#define MAC_BASE_ADDR		((priv->mac_base))
+
+#define CTRL_REG		(MAC_BASE_ADDR)
+#define  MII_BUSY		(1 << 0)
+#define  MII_WRITE		(1 << 1)
+#define  RX_ENABLE		(1 << 2)
+#define  TX_ENABLE		(1 << 3)
+#define  DEFER_CHECK		(1 << 5)
+#define  STRIP_PAD		(1 << 8)
+#define  DRTRY_DISABLE		(1 << 10)
+#define  FULL_DUPLEX		(1 << 20)
+#define  HBD_DISABLE		(1 << 28)
+#define MAC_ADDR_HIGH_REG	(MAC_BASE_ADDR + 0x04)
+#define MAC_ADDR_LOW_REG	(MAC_BASE_ADDR + 0x08)
+#define MII_ADDR_REG		(MAC_BASE_ADDR + 0x14)
+#define  MII_ADDR_SHIFT		(11)
+#define  MII_REG_SHIFT		(6)
+#define MII_DATA_REG		(MAC_BASE_ADDR + 0x18)
+/* Link interrupt registers */
+#define LINK_INT_CSR		(MAC_BASE_ADDR + 0xD0)
+#define  LINK_INT_EN		(1 << 0)
+#define  LINK_PHY_ADDR_SHIFT	(1)
+#define  LINK_PHY_REG_SHIFT	(6)
+#define  LINK_BIT_UP_SHIFT	(11)
+#define  LINK_UP		(1 << 16)
+#define LINK_INT_POLL_TIME	(MAC_BASE_ADDR + 0xD4)
+#define  LINK_POLL_MASK		((1 << 20) - 1)
+
+#define DMA_CHAN_WIDTH		32
+#define DMA_RX_CHAN		0
+#define DMA_TX_CHAN		2
+
+/* Receive DMA registers */
+#define RX_DMA_BASE		((priv->dma_base) + \
+				(DMA_CHAN_WIDTH * DMA_RX_CHAN))
+#define RX_BUFFER_ADDR		(RX_DMA_BASE + 0x00)
+#define RX_MAX_BYTES		(RX_DMA_BASE + 0x04)
+#define RX_ACT_BYTES		(RX_DMA_BASE + 0x08)
+#define RX_START_DMA		(RX_DMA_BASE + 0x0C)
+#define  RX_DMA_ENABLE		(1 << 0)
+#define  RX_DMA_RESET		(1 << 1)
+#define  RX_DMA_STATUS_FIFO	(1 << 12)
+#define RX_DMA_ENH		(RX_DMA_BASE + 0x14)
+#define  RX_DMA_INT_ENABLE	(1 << 1)
+
+/* Transmit DMA registers */
+#define TX_DMA_BASE		((priv->dma_base) + \
+				(DMA_CHAN_WIDTH * DMA_TX_CHAN))
+#define TX_BUFFER_ADDR		(TX_DMA_BASE + 0x00)
+#define TX_PKT_BYTES		(TX_DMA_BASE + 0x04)
+#define TX_BYTES_SENT		(TX_DMA_BASE + 0x08)
+#define TX_START_DMA		(TX_DMA_BASE + 0x0C)
+#define  TX_DMA_ENABLE		(1 << 0)
+#define  TX_DMA_START_FRAME	(1 << 2)
+#define  TX_DMA_END_FRAME	(1 << 3)
+#define  TX_DMA_PAD_DISABLE	(1 << 8)
+#define  TX_DMA_CRC_DISABLE	(1 << 9)
+#define  TX_DMA_FIFO_FULL	(1 << 16)
+#define  TX_DMA_FIFO_EMPTY	(1 << 17)
+#define  TX_DMA_STATUS_AVAIL	(1 << 18)
+#define  TX_DMA_RESET		(1 << 24)
+#define TX_DMA_STATUS		(TX_DMA_BASE + 0x10)
+#define TX_DMA_ENH		(TX_DMA_BASE + 0x14)
+#define  TX_DMA_ENH_ENABLE	(1 << 0)
+#define  TX_DMA_INT_FIFO	(1 << 1)
+
+#define RX_ALLOC_SIZE		SZ_2K
+#define MAX_ETH_FRAME_SIZE	1536
+#define RX_SKB_TAILROOM		128
+#define RX_SKB_HEADROOM		(RX_ALLOC_SIZE  - \
+				(MAX_ETH_FRAME_SIZE + RX_SKB_TAILROOM) + 0)
+
+			/* WDT     Late COL    Lenght     COL      Type */
+#define ERROR_FILTER_MASK ((1<<14) | (1<<15) | (1<<16) | (1<<17) | (0<<18) | \
+			/* MII    Dribbling    CRC    Len/type   Control */\
+			(1<<19) | (1<<20) | (1<<21) | (0<<24) | (1<<25) | \
+			/* Unsup   Missed */\
+			(1<<26) | (0<<31))
+#define  TX_RING_SIZE  30
+#define  RX_RING_SIZE  30
+
+static inline u32 nuport_mac_readl(void __iomem *reg)
+{
+	return readl_relaxed(reg);
+}
+
+static inline u8 nuport_mac_readb(void __iomem *reg)
+{
+	return readb_relaxed(reg);
+}
+
+static inline void nuport_mac_writel(u32 value, void __iomem *reg)
+{
+	writel_relaxed(value, reg);
+}
+
+static inline void nuport_mac_writeb(u8 value, void __iomem *reg)
+{
+	writel_relaxed(value, reg);
+}
+
+/* MAC private data */
+struct nuport_mac_priv {
+	spinlock_t lock;
+
+	void __iomem	*mac_base;
+	void __iomem	*dma_base;
+
+	int		rx_irq;
+	int		tx_irq;
+	int		link_irq;
+	struct clk	*emac_clk;
+	struct clk	*ephy_clk;
+
+	/* Transmit buffers */
+	struct sk_buff *tx_skb[TX_RING_SIZE];
+	dma_addr_t tx_addr;
+	unsigned int valid_txskb[TX_RING_SIZE];
+	unsigned int cur_tx;
+	unsigned int dma_tx;
+	unsigned int tx_full;
+
+	/* Receive buffers */
+	struct sk_buff *rx_skb[RX_RING_SIZE];
+	dma_addr_t rx_addr;
+	unsigned int irq_rxskb[RX_RING_SIZE];
+	int pkt_len[RX_RING_SIZE];
+	unsigned int cur_rx;
+	unsigned int dma_rx;
+	unsigned int rx_full;
+
+	unsigned int first_pkt;
+
+	/* Private data */
+	struct napi_struct napi;
+	struct net_device	*dev;
+	struct platform_device	*pdev;
+	struct mii_bus		*mii_bus;
+	struct phy_device	*phydev;
+	int			old_link;
+	int			old_duplex;
+	u32			msg_level;
+	unsigned int		buffer_shifting_len;
+};
+
+static inline int nuport_mac_mii_busy_wait(struct nuport_mac_priv *priv)
+{
+	unsigned long curr;
+	unsigned long finish = jiffies + 3 * HZ;
+
+	do {
+		curr = jiffies;
+		if (!(nuport_mac_readl(MII_ADDR_REG) & MII_BUSY))
+			return 0;
+		cpu_relax();
+	} while (!time_after_eq(curr, finish));
+
+	return -EBUSY;
+}
+
+/* Read from PHY registers */
+static int nuport_mac_mii_read(struct mii_bus *bus,
+				int mii_id, int regnum)
+{
+	struct net_device *dev = bus->priv;
+	struct nuport_mac_priv *priv = netdev_priv(dev);
+	int ret;
+	u32 val = 0;
+
+	ret = nuport_mac_mii_busy_wait(priv);
+	if (ret)
+		return ret;
+
+	val |= (mii_id << MII_ADDR_SHIFT) | (regnum << MII_REG_SHIFT) | MII_BUSY;
+	nuport_mac_writel(val, MII_ADDR_REG);
+	ret = nuport_mac_mii_busy_wait(priv);
+	if (ret)
+		return ret;
+
+	return nuport_mac_readl(MII_DATA_REG);
+}
+
+static int nuport_mac_mii_write(struct mii_bus *bus, int mii_id,
+				int regnum, u16 value)
+{
+	struct net_device *dev = bus->priv;
+	struct nuport_mac_priv *priv = netdev_priv(dev);
+	int ret;
+	u32 val = 0;
+
+	ret = nuport_mac_mii_busy_wait(priv);
+	if (ret)
+		return ret;
+
+	val |= (mii_id << MII_ADDR_SHIFT) | (regnum << MII_REG_SHIFT);
+	val |= MII_BUSY | MII_WRITE;
+	nuport_mac_writel(value, MII_DATA_REG);
+	nuport_mac_writel(val, MII_ADDR_REG);
+
+	return nuport_mac_mii_busy_wait(priv);
+}
+
+static int nuport_mac_mii_reset(struct mii_bus *bus)
+{
+	return 0;
+}
+
+static int nuport_mac_start_tx_dma(struct nuport_mac_priv *priv,
+					struct sk_buff *skb)
+{
+	u32 reg;
+	unsigned int timeout = 2048;
+
+	while (timeout--) {
+		reg = nuport_mac_readl(TX_START_DMA);
+		if (!(reg & TX_DMA_ENABLE)) {
+			netdev_dbg(priv->dev, "dma ready\n");
+			break;
+		}
+		cpu_relax();
+	}
+
+	if (!timeout)
+		return -EBUSY;
+
+	priv->tx_addr = dma_map_single(&priv->pdev->dev, skb->data,
+			skb->len, DMA_TO_DEVICE);
+	if (dma_mapping_error(&priv->pdev->dev, priv->tx_addr))
+		return -ENOMEM;
+
+	/* enable enhanced mode */
+	nuport_mac_writel(TX_DMA_ENH_ENABLE, TX_DMA_ENH);
+	nuport_mac_writel(priv->tx_addr, TX_BUFFER_ADDR);
+	nuport_mac_writel((skb->len) - 1, TX_PKT_BYTES);
+	wmb();
+	reg = TX_DMA_ENABLE | TX_DMA_START_FRAME | TX_DMA_END_FRAME;
+	nuport_mac_writel(reg, TX_START_DMA);
+
+	return 0;
+}
+
+static void nuport_mac_reset_tx_dma(struct nuport_mac_priv *priv)
+{
+	u32 reg;
+
+	reg = nuport_mac_readl(TX_START_DMA);
+	reg |= TX_DMA_RESET;
+	nuport_mac_writel(reg, TX_START_DMA);
+}
+
+static int nuport_mac_start_rx_dma(struct nuport_mac_priv *priv,
+					struct sk_buff *skb)
+{
+	u32 reg;
+	unsigned int timeout = 2048;
+
+	while (timeout--) {
+		reg = nuport_mac_readl(RX_START_DMA);
+		if (!(reg & RX_DMA_ENABLE)) {
+			netdev_dbg(priv->dev, "dma ready\n");
+			break;
+		}
+		cpu_relax();
+	}
+
+	if (!timeout)
+		return -EBUSY;
+
+	priv->rx_addr = dma_map_single(&priv->pdev->dev, skb->data,
+				RX_ALLOC_SIZE, DMA_FROM_DEVICE);
+	if (dma_mapping_error(&priv->pdev->dev, priv->rx_addr))
+		return -ENOMEM;
+
+	nuport_mac_writel(priv->rx_addr, RX_BUFFER_ADDR);
+	wmb();
+	nuport_mac_writel(RX_DMA_ENABLE, RX_START_DMA);
+
+	return 0;
+}
+
+static void nuport_mac_reset_rx_dma(struct nuport_mac_priv *priv)
+{
+	u32 reg;
+
+	reg = nuport_mac_readl(RX_START_DMA);
+	reg |= RX_DMA_RESET;
+	nuport_mac_writel(reg, RX_START_DMA);
+}
+
+/* I suppose this might do something, but I am not sure actually */
+static void nuport_mac_disable_rx_dma(struct nuport_mac_priv *priv)
+{
+	u32 reg;
+
+	reg = nuport_mac_readl(RX_DMA_ENH);
+	reg &= ~RX_DMA_INT_ENABLE;
+	nuport_mac_writel(reg, RX_DMA_ENH);
+}
+
+static void nuport_mac_enable_rx_dma(struct nuport_mac_priv *priv)
+{
+	u32 reg;
+
+	reg = nuport_mac_readl(RX_DMA_ENH);
+	reg |= RX_DMA_INT_ENABLE;
+	nuport_mac_writel(reg, RX_DMA_ENH);
+}
+
+/* Add packets to the transmit queue */
+static int nuport_mac_start_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	unsigned long flags;
+	struct nuport_mac_priv *priv = netdev_priv(dev);
+	int ret;
+
+	if (netif_queue_stopped(dev)) {
+		netdev_warn(dev, "netif queue was stopped, restarting\n");
+		netif_start_queue(dev);
+	}
+
+	spin_lock_irqsave(&priv->lock, flags);
+	if (priv->first_pkt) {
+		ret = nuport_mac_start_tx_dma(priv, skb);
+		if (ret) {
+			netif_stop_queue(dev);
+			spin_unlock_irqrestore(&priv->lock, flags);
+			netdev_err(dev, "transmit path busy\n");
+			return NETDEV_TX_BUSY;
+		}
+		priv->first_pkt = 0;
+	}
+
+	priv->tx_skb[priv->cur_tx] = skb;
+	dev->stats.tx_bytes += skb->len;
+	dev->stats.tx_packets++;
+	priv->valid_txskb[priv->cur_tx] = 1;
+	priv->cur_tx++;
+	dev->trans_start = jiffies;
+
+	if (priv->cur_tx >= TX_RING_SIZE)
+		priv->cur_tx = 0;
+
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	if (priv->valid_txskb[priv->cur_tx]) {
+		priv->tx_full = 1;
+		netdev_err(dev, "stopping queue\n");
+		netif_stop_queue(dev);
+	}
+
+	return NETDEV_TX_OK;
+}
+
+static void nuport_mac_adjust_link(struct net_device *dev)
+{
+	struct nuport_mac_priv *priv = netdev_priv(dev);
+	struct phy_device *phydev = priv->phydev;
+	unsigned int status_changed = 0;
+	u32 reg;
+
+	BUG_ON(!phydev);
+
+	if (priv->old_link != phydev->link) {
+		status_changed = 1;
+		priv->old_link = phydev->link;
+	}
+
+	if (phydev->link & (priv->old_duplex != phydev->duplex)) {
+		reg = nuport_mac_readl(CTRL_REG);
+		if (phydev->duplex == DUPLEX_FULL)
+			reg |= DUPLEX_FULL;
+		else
+			reg &= ~DUPLEX_FULL;
+		nuport_mac_writel(reg, CTRL_REG);
+
+		status_changed = 1;
+		priv->old_duplex = phydev->duplex;
+	}
+
+	if (!status_changed)
+		return;
+
+	pr_info("%s: link %s", dev->name, phydev->link ?
+		"UP" : "DOWN");
+	if (phydev->link) {
+		pr_cont(" - %d/%s", phydev->speed,
+		phydev->duplex == DUPLEX_FULL ? "full" : "half");
+	}
+	pr_cont("\n");
+}
+
+static irqreturn_t nuport_mac_link_interrupt(int irq, void *dev_id)
+{
+	struct net_device *dev = dev_id;
+	struct nuport_mac_priv *priv = netdev_priv(dev);
+	u32 reg;
+	u8 phy_addr;
+	unsigned long flags;
+	irqreturn_t ret = IRQ_HANDLED;
+
+	spin_lock_irqsave(&priv->lock, flags);
+	reg = nuport_mac_readl(LINK_INT_CSR);
+	phy_addr = (reg >> LINK_PHY_ADDR_SHIFT) & (PHY_MAX_ADDR - 1);
+
+	if (phy_addr != priv->phydev->addr) {
+		netdev_err(dev, "spurious PHY irq (phy: %d)\n", phy_addr);
+		ret = IRQ_NONE;
+		goto out;
+	}
+
+	priv->phydev->link = (reg & LINK_UP);
+	nuport_mac_adjust_link(dev);
+
+out:
+	spin_unlock_irqrestore(&priv->lock, flags);
+	return ret;
+}
+
+static irqreturn_t nuport_mac_tx_interrupt(int irq, void *dev_id)
+{
+	struct net_device *dev = (struct net_device *)dev_id;
+	struct nuport_mac_priv *priv = netdev_priv(dev);
+	struct sk_buff *skb;
+	unsigned long flags;
+	int ret;
+	u32 reg;
+
+	spin_lock_irqsave(&priv->lock, flags);
+	/* clear status word available if ready */
+	reg = nuport_mac_readl(TX_START_DMA);
+	if (reg & TX_DMA_STATUS_AVAIL) {
+		nuport_mac_writel(reg, TX_START_DMA);
+		reg = nuport_mac_readl(TX_DMA_STATUS);
+
+		if (reg & 1)
+			dev->stats.tx_errors++;
+	} else
+		netdev_dbg(dev, "no status word: %08x\n", reg);
+
+	skb = priv->tx_skb[priv->dma_tx];
+	priv->tx_skb[priv->dma_tx] = NULL;
+	priv->valid_txskb[priv->dma_tx] = 0;
+	dma_unmap_single(&priv->pdev->dev, priv->rx_addr, skb->len,
+				DMA_TO_DEVICE);
+	dev_kfree_skb_irq(skb);
+
+	priv->dma_tx++;
+	if (priv->dma_tx >= TX_RING_SIZE)
+		priv->dma_tx = 0;
+
+	if (!priv->valid_txskb[priv->dma_tx])
+		priv->first_pkt = 1;
+	else {
+		ret = nuport_mac_start_tx_dma(priv, priv->tx_skb[priv->dma_tx]);
+		if (ret)
+			netdev_err(dev, "failed to restart TX dma\n");
+	}
+
+	if (priv->tx_full) {
+		netdev_dbg(dev, "restarting transmit queue\n");
+		netif_wake_queue(dev);
+		priv->tx_full = 0;
+	}
+
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	return IRQ_HANDLED;
+}
+
+static unsigned int nuport_mac_has_work(struct nuport_mac_priv *priv)
+{
+	unsigned int i;
+
+	for (i = 0; i < RX_RING_SIZE; i++)
+		if (priv->rx_skb[i])
+			return 1;
+
+	return 0;
+}
+
+static irqreturn_t nuport_mac_rx_interrupt(int irq, void *dev_id)
+{
+	struct net_device *dev = (struct net_device *)dev_id;
+	struct nuport_mac_priv *priv = netdev_priv(dev);
+	unsigned long flags;
+	int ret;
+
+	spin_lock_irqsave(&priv->lock, flags);
+	if (!priv->rx_full) {
+		priv->pkt_len[priv->dma_rx] = nuport_mac_readl(RX_ACT_BYTES) - 4;
+		priv->irq_rxskb[priv->dma_rx] = 0;
+		priv->dma_rx++;
+
+		if (priv->dma_rx >= RX_RING_SIZE)
+			priv->dma_rx = 0;
+	} else
+		priv->rx_full = 0;
+
+	if (priv->irq_rxskb[priv->dma_rx] == 1) {
+		ret = nuport_mac_start_rx_dma(priv, priv->rx_skb[priv->dma_rx]);
+		if (ret)
+			netdev_err(dev, "failed to start rx dma\n");
+	} else {
+		priv->rx_full = 1;
+		netdev_dbg(dev, "RX ring full\n");
+	}
+
+	if (likely(nuport_mac_has_work(priv))) {
+		/* find a way to disable DMA rx irq */
+		nuport_mac_disable_rx_dma(priv);
+		napi_schedule(&priv->napi);
+	}
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	return IRQ_HANDLED;
+}
+
+/* Process received packets in tasklet */
+static int nuport_mac_rx(struct net_device *dev, int limit)
+{
+	struct nuport_mac_priv *priv = netdev_priv(dev);
+	struct sk_buff *skb;
+	int len, status;
+	int count = 0;
+
+	while (count < limit && !priv->irq_rxskb[priv->cur_rx]) {
+		skb = priv->rx_skb[priv->cur_rx];
+		len = priv->pkt_len[priv->cur_rx];
+
+		/* Remove 2 bytes added by RX buffer shifting */
+		len = len - priv->buffer_shifting_len;
+		skb->data = skb->data + priv->buffer_shifting_len;
+
+		/* Get packet status */
+		status = get_unaligned((u32 *) (skb->data + len));
+		skb->dev = dev;
+
+		dma_unmap_single(&priv->pdev->dev, priv->rx_addr, skb->len,
+				DMA_FROM_DEVICE);
+
+		/* packet filter failed */
+		if (!(status & (1 << 30))) {
+			dev_kfree_skb_irq(skb);
+			goto exit;
+		}
+
+		/* missed frame */
+		if (status & (1 << 31)) {
+			dev->stats.rx_missed_errors++;
+			dev_kfree_skb_irq(skb);
+			goto exit;
+		}
+
+		/* Not ethernet type */
+		if ((!(status & (1 << 18))) || (status & ERROR_FILTER_MASK))
+			dev->stats.rx_errors++;
+
+		if (len > MAX_ETH_FRAME_SIZE) {
+			dev_kfree_skb_irq(skb);
+			goto exit;
+		} else
+			skb_put(skb, len);
+
+		skb->protocol = eth_type_trans(skb, dev);
+		dev->stats.rx_packets++;
+
+		if (status & (1 << 29))
+			skb->pkt_type = PACKET_OTHERHOST;
+		if (status & (1 << 27))
+			skb->pkt_type = PACKET_MULTICAST;
+		if (status & (1 << 28))
+			skb->pkt_type = PACKET_BROADCAST;
+
+		skb->ip_summed = CHECKSUM_UNNECESSARY;
+
+		/* Pass the received packet to network layer */
+		status = netif_receive_skb(skb);
+		if (status != NET_RX_DROP)
+			dev->stats.rx_bytes += len - 4;	/* Without CRC */
+		else
+			dev->stats.rx_dropped++;
+
+		dev->last_rx = jiffies;
+
+exit:
+		skb = netdev_alloc_skb(dev, RX_ALLOC_SIZE);
+		skb_reserve(skb, RX_SKB_HEADROOM);
+		priv->rx_skb[priv->cur_rx] = skb;
+		priv->irq_rxskb[priv->cur_rx] = 1;
+		priv->cur_rx++;
+
+		if (priv->cur_rx >= RX_RING_SIZE)
+			priv->cur_rx = 0;
+		count++;
+	}
+
+	return count;
+}
+
+static int nuport_mac_poll(struct napi_struct *napi, int budget)
+{
+	struct nuport_mac_priv *priv =
+		container_of(napi, struct nuport_mac_priv, napi);
+	struct net_device *dev = priv->dev;
+	int work_done;
+
+	work_done = nuport_mac_rx(dev, budget);
+
+	if (work_done < budget) {
+		napi_complete(napi);
+		nuport_mac_enable_rx_dma(priv);
+	}
+
+	return work_done;
+}
+
+static void nuport_mac_init_tx_ring(struct nuport_mac_priv *priv)
+{
+	int i;
+
+	priv->cur_tx = priv->dma_tx = priv->tx_full = 0;
+	for (i = 0; i < TX_RING_SIZE; i++) {
+		priv->tx_skb[i] = NULL;
+		priv->valid_txskb[i] = 0;
+	}
+	priv->first_pkt = 1;
+}
+
+static int nuport_mac_init_rx_ring(struct net_device *dev)
+{
+	struct nuport_mac_priv *priv = netdev_priv(dev);
+	struct sk_buff *skb;
+	int i;
+
+	priv->cur_rx = priv->dma_rx = priv->rx_full = 0;
+
+	for (i = 0; i < RX_RING_SIZE; i++) {
+		skb = netdev_alloc_skb(dev, RX_ALLOC_SIZE);
+		if (!skb)
+			return -ENOMEM;
+		skb_reserve(skb, RX_SKB_HEADROOM);
+		priv->rx_skb[i] = skb;
+		priv->irq_rxskb[i] = 1;
+	}
+
+	return 0;
+}
+
+static void nuport_mac_free_rx_ring(struct nuport_mac_priv *priv)
+{
+	int i;
+
+	for (i = 0; i < RX_RING_SIZE; i++) {
+		if (!priv->rx_skb[i])
+			continue;
+
+		dev_kfree_skb(priv->rx_skb[i]);
+		priv->rx_skb[i] = NULL;
+	}
+
+	if (priv->rx_addr)
+		dma_unmap_single(&priv->pdev->dev, priv->rx_addr, RX_ALLOC_SIZE,
+				DMA_TO_DEVICE);
+}
+
+static void nuport_mac_read_mac_address(struct net_device *dev)
+{
+	struct nuport_mac_priv *priv = netdev_priv(dev);
+	int i;
+
+	for (i = 0; i < 4; i++)
+		dev->dev_addr[i] = nuport_mac_readb(MAC_ADDR_LOW_REG + i);
+	dev->dev_addr[4] = nuport_mac_readb(MAC_ADDR_HIGH_REG);
+	dev->dev_addr[5] = nuport_mac_readb(MAC_ADDR_HIGH_REG + 1);
+
+	if (!is_valid_ether_addr(dev->dev_addr)) {
+		dev_info(&priv->pdev->dev, "using random address\n");
+		random_ether_addr(dev->dev_addr);
+	}
+}
+
+static int nuport_mac_change_mac_address(struct net_device *dev, void *mac_addr)
+{
+	struct sockaddr *addr = mac_addr;
+	struct nuport_mac_priv *priv = netdev_priv(dev);
+	unsigned long *temp = (unsigned long *)dev->dev_addr;
+	u32 high, low;
+
+	if (netif_running(dev))
+		return -EBUSY;
+
+	memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN);
+
+	spin_lock_irq(&priv->lock);
+
+	nuport_mac_writel(*temp, MAC_ADDR_LOW_REG);
+	temp = (unsigned long *)(dev->dev_addr + 4);
+	nuport_mac_writel(*temp, MAC_ADDR_HIGH_REG);
+
+	low = nuport_mac_readl(MAC_ADDR_LOW_REG);
+	high = nuport_mac_readl(MAC_ADDR_HIGH_REG);
+
+	spin_unlock_irq(&priv->lock);
+
+	return 0;
+}
+
+static int nuport_mac_open(struct net_device *dev)
+{
+	int ret;
+	struct nuport_mac_priv *priv = netdev_priv(dev);
+	unsigned long flags;
+	u32 reg = 0;
+
+	ret = clk_enable(priv->emac_clk);
+	if (ret) {
+		netdev_err(dev, "failed to enable EMAC clock\n");
+		return ret;
+	}
+
+	/* Set MAC into full duplex mode by default */
+	reg |= RX_ENABLE | TX_ENABLE;
+	reg |= DEFER_CHECK | STRIP_PAD | DRTRY_DISABLE;
+	reg |= FULL_DUPLEX | HBD_DISABLE;
+	nuport_mac_writel(reg, CTRL_REG);
+
+	/* set mac address in hardware in case it was not already */
+	nuport_mac_change_mac_address(dev, dev->dev_addr);
+
+	ret = request_irq(priv->link_irq, &nuport_mac_link_interrupt,
+				0, dev->name, dev);
+	if (ret) {
+		netdev_err(dev, "unable to request link interrupt\n");
+		goto out_emac_clk;
+	}
+
+	ret = request_irq(priv->tx_irq, &nuport_mac_tx_interrupt,
+				0, dev->name, dev);
+	if (ret) {
+		netdev_err(dev, "unable to request rx interrupt\n");
+		goto out_link_irq;
+	}
+
+	/* Enable link interrupt monitoring for our PHY address */
+	reg = LINK_INT_EN | (priv->phydev->addr << LINK_PHY_ADDR_SHIFT);
+	/* MII_BMSR register to be watched */
+	reg |= (1 << LINK_PHY_REG_SHIFT);
+	/* BMSR_STATUS to be watched in particular */
+	reg |= (2 << LINK_BIT_UP_SHIFT);
+
+	spin_lock_irqsave(&priv->lock, flags);
+	nuport_mac_writel(reg, LINK_INT_CSR);
+	nuport_mac_writel(LINK_POLL_MASK, LINK_INT_POLL_TIME);
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	phy_start(priv->phydev);
+
+	ret = request_irq(priv->rx_irq, &nuport_mac_rx_interrupt,
+				0, dev->name, dev);
+	if (ret) {
+		netdev_err(dev, "unable to request tx interrupt\n");
+		goto out_tx_irq;
+	}
+
+	netif_start_queue(dev);
+
+	nuport_mac_init_tx_ring(priv);
+
+	ret = nuport_mac_init_rx_ring(dev);
+	if (ret) {
+		netdev_err(dev, "rx ring init failed\n");
+		goto out_rx_skb;
+	}
+
+	nuport_mac_reset_tx_dma(priv);
+	nuport_mac_reset_rx_dma(priv);
+
+	/* Start RX DMA */
+	spin_lock_irqsave(&priv->lock, flags);
+	ret = nuport_mac_start_rx_dma(priv, priv->rx_skb[0]);
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	napi_enable(&priv->napi);
+
+	return ret;
+
+out_rx_skb:
+	nuport_mac_free_rx_ring(priv);
+	free_irq(priv->rx_irq, dev);
+out_tx_irq:
+	free_irq(priv->tx_irq, dev);
+out_link_irq:
+	free_irq(priv->link_irq, dev);
+out_emac_clk:
+	clk_disable(priv->emac_clk);
+	return ret;
+}
+
+static int nuport_mac_close(struct net_device *dev)
+{
+	u32 reg;
+	struct nuport_mac_priv *priv = netdev_priv(dev);
+
+	spin_lock_irq(&priv->lock);
+	reg = nuport_mac_readl(CTRL_REG);
+	reg &= ~(RX_ENABLE | TX_ENABLE);
+	nuport_mac_writel(reg, CTRL_REG);
+
+	napi_disable(&priv->napi);
+	netif_stop_queue(dev);
+
+	free_irq(priv->link_irq, dev);
+	/* disable PHY polling */
+	nuport_mac_writel(0, LINK_INT_CSR);
+	nuport_mac_writel(0, LINK_INT_POLL_TIME);
+	phy_stop(priv->phydev);
+
+	free_irq(priv->tx_irq, dev);
+	free_irq(priv->rx_irq, dev);
+	spin_unlock_irq(&priv->lock);
+
+	nuport_mac_free_rx_ring(priv);
+
+	clk_disable(priv->emac_clk);
+
+	return 0;
+}
+
+static void nuport_mac_tx_timeout(struct net_device *dev)
+{
+	struct nuport_mac_priv *priv = netdev_priv(dev);
+	unsigned int i;
+
+	netdev_warn(dev, "transmit timeout, attempting recovery\n");
+
+	netdev_info(dev, "TX DMA regs\n");
+	for (i = 0; i < DMA_CHAN_WIDTH; i += 4)
+		netdev_info(dev, "[%02x]: 0x%08x\n", i, nuport_mac_readl(TX_DMA_BASE + i));
+	netdev_info(dev, "RX DMA regs\n");
+	for (i = 0; i < DMA_CHAN_WIDTH; i += 4)
+		netdev_info(dev, "[%02x]: 0x%08x\n", i, nuport_mac_readl(RX_DMA_BASE + i));
+
+	nuport_mac_init_tx_ring(priv);
+	nuport_mac_reset_tx_dma(priv);
+
+	netif_wake_queue(dev);
+}
+
+static int nuport_mac_mii_probe(struct net_device *dev)
+{
+	struct nuport_mac_priv *priv = netdev_priv(dev);
+	struct phy_device *phydev = NULL;
+	int ret;
+
+	ret = clk_enable(priv->ephy_clk);
+	if (ret) {
+		netdev_err(dev, "unable to enable ePHY clk\n");
+		return ret;
+	}
+
+	phydev = phy_find_first(priv->mii_bus);
+	if (!phydev) {
+		netdev_err(dev, "no PHYs found\n");
+		ret = -ENODEV;
+		goto out;
+	}
+
+	phydev = phy_connect(dev, dev_name(&phydev->dev),
+			nuport_mac_adjust_link, 0,
+			PHY_INTERFACE_MODE_MII);
+	if (IS_ERR(phydev)) {
+		netdev_err(dev, "could not attach PHY\n");
+		ret = PTR_ERR(phydev);
+		goto out;
+	}
+
+	phydev->supported &= PHY_BASIC_FEATURES;
+	phydev->advertising = phydev->supported;
+	priv->phydev = phydev;
+	priv->old_link = 1;
+	priv->old_duplex = DUPLEX_FULL;
+
+	dev_info(&priv->pdev->dev, "attached PHY driver [%s] "
+		"(mii_bus:phy_addr=%d)\n",
+		phydev->drv->name, phydev->addr);
+
+	return 0;
+
+out:
+	/* disable the Ethernet PHY clock for the moment */
+	clk_disable(priv->ephy_clk);
+
+	return ret;
+}
+
+static void nuport_mac_ethtool_drvinfo(struct net_device *dev,
+					struct ethtool_drvinfo *info)
+{
+	strncpy(info->driver, "nuport-mac", sizeof(info->driver));
+	strncpy(info->version, "0.1", sizeof(info->version));
+	strncpy(info->fw_version, "N/A", sizeof(info->fw_version));
+	strncpy(info->bus_info, "internal", sizeof(info->bus_info));
+	info->n_stats = 0;
+	info->testinfo_len = 0;
+	info->regdump_len = 0;
+	info->eedump_len = 0;
+}
+
+static int nuport_mac_ethtool_get_settings(struct net_device *dev,
+					struct ethtool_cmd *cmd)
+{
+	struct nuport_mac_priv *priv = netdev_priv(dev);
+
+	if (priv->phydev)
+		return phy_ethtool_gset(priv->phydev, cmd);
+
+	return -EINVAL;
+}
+
+static int nuport_mac_ethtool_set_settings(struct net_device *dev,
+					struct ethtool_cmd *cmd)
+{
+	struct nuport_mac_priv *priv = netdev_priv(dev);
+
+	if (priv->phydev)
+		return phy_ethtool_sset(priv->phydev, cmd);
+
+	return -EINVAL;
+}
+
+static void nuport_mac_set_msglevel(struct net_device *dev, u32 msg_level)
+{
+	struct nuport_mac_priv *priv = netdev_priv(dev);
+
+	priv->msg_level = msg_level;
+}
+
+static u32 nuport_mac_get_msglevel(struct net_device *dev)
+{
+	struct nuport_mac_priv *priv = netdev_priv(dev);
+
+	return priv->msg_level;
+}
+
+static const struct ethtool_ops nuport_mac_ethtool_ops = {
+	.get_drvinfo		= nuport_mac_ethtool_drvinfo,
+	.get_link		= ethtool_op_get_link,
+	.get_settings		= nuport_mac_ethtool_get_settings,
+	.set_settings		= nuport_mac_ethtool_set_settings,
+	.set_msglevel		= nuport_mac_set_msglevel,
+	.get_msglevel		= nuport_mac_get_msglevel,
+};
+
+static const struct net_device_ops nuport_mac_ops = {
+	.ndo_open		= nuport_mac_open,
+	.ndo_stop		= nuport_mac_close,
+	.ndo_start_xmit		= nuport_mac_start_xmit,
+	.ndo_change_mtu		= eth_change_mtu,
+	.ndo_validate_addr	= eth_validate_addr,
+	.ndo_set_mac_address	= nuport_mac_change_mac_address,
+	.ndo_tx_timeout		= nuport_mac_tx_timeout,
+};
+
+static int __init nuport_mac_probe(struct platform_device *pdev)
+{
+	struct net_device *dev;
+	struct nuport_mac_priv *priv = NULL;
+	struct resource *regs, *dma;
+	int ret = 0;
+	int rx_irq, tx_irq, link_irq;
+	int i;
+	const unsigned int *intspec;
+
+	dev = alloc_etherdev(sizeof(struct nuport_mac_priv));
+	if (!dev) {
+		dev_err(&pdev->dev, "no memory for net_device\n");
+		return -ENOMEM;
+	}
+
+	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	dma = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+	if (!regs || !dma) {
+		dev_err(&pdev->dev, "failed to get regs resources\n");
+		ret = -ENODEV;
+		goto out;
+	}
+
+	rx_irq = platform_get_irq(pdev, 0);
+	tx_irq = platform_get_irq(pdev, 1);
+	link_irq = platform_get_irq(pdev, 2);
+	if (rx_irq < 0 || tx_irq < 0 || link_irq < 0) {
+		ret = -ENODEV;
+		goto out;
+	}
+
+	platform_set_drvdata(pdev, dev);
+	SET_NETDEV_DEV(dev, &pdev->dev);
+	priv = netdev_priv(dev);
+	priv->pdev = pdev;
+	priv->dev = dev;
+	spin_lock_init(&priv->lock);
+
+	intspec = of_get_property(pdev->dev.of_node,
+				"nuport-mac,buffer-shifting", NULL);
+	if (!intspec)
+		priv->buffer_shifting_len = 0;
+	else
+		priv->buffer_shifting_len = 2;
+
+	priv->mac_base = devm_ioremap(&pdev->dev,
+				regs->start, resource_size(regs));
+	if (!priv->mac_base) {
+		dev_err(&pdev->dev, "failed to remap regs\n");
+		ret = -ENOMEM;
+		goto out_platform;
+	}
+
+	priv->dma_base = devm_ioremap(&pdev->dev,
+				dma->start, resource_size(dma));
+	if (!priv->dma_base) {
+		dev_err(&pdev->dev, "failed to remap dma-regs\n");
+		ret = -ENOMEM;
+		goto out_platform;
+	}
+
+	priv->emac_clk = clk_get(&pdev->dev, "emac");
+	if (IS_ERR_OR_NULL(priv->emac_clk)) {
+		dev_err(&pdev->dev, "failed to get emac clk\n");
+		ret = PTR_ERR(priv->emac_clk);
+		goto out_platform;
+	}
+
+	priv->ephy_clk = clk_get(&pdev->dev, "ephy");
+	if (IS_ERR_OR_NULL(priv->ephy_clk)) {
+		dev_err(&pdev->dev, "failed to get ephy clk\n");
+		ret = PTR_ERR(priv->ephy_clk);
+		goto out_platform;
+	}
+
+	priv->link_irq = link_irq;
+	priv->rx_irq = rx_irq;
+	priv->tx_irq = tx_irq;
+	priv->msg_level = NETIF_MSG_DRV | NETIF_MSG_PROBE | NETIF_MSG_LINK;
+	dev->netdev_ops = &nuport_mac_ops;
+	dev->ethtool_ops = &nuport_mac_ethtool_ops;
+	dev->watchdog_timeo = HZ;
+	dev->flags = IFF_BROADCAST;	/* Supports Broadcast */
+	dev->tx_queue_len = TX_RING_SIZE / 2;
+
+	netif_napi_add(dev, &priv->napi, nuport_mac_poll, 64);
+
+	priv->mii_bus = mdiobus_alloc();
+	if (!priv->mii_bus) {
+		dev_err(&pdev->dev, "mii bus allocation failed\n");
+		goto out;
+	}
+
+	priv->mii_bus->priv = dev;
+	priv->mii_bus->read = nuport_mac_mii_read;
+	priv->mii_bus->write = nuport_mac_mii_write;
+	priv->mii_bus->reset = nuport_mac_mii_reset;
+	priv->mii_bus->name = "nuport-mac-mii";
+	priv->mii_bus->phy_mask = (1 << 0);
+	snprintf(priv->mii_bus->id, MII_BUS_ID_SIZE, "%s", pdev->name);
+	priv->mii_bus->irq = kzalloc(PHY_MAX_ADDR * sizeof(int), GFP_KERNEL);
+	if (!priv->mii_bus->irq) {
+		dev_err(&pdev->dev, "failed to allocate mii_bus irqs\n");
+		ret = -ENOMEM;
+		goto out_mdio;
+	}
+
+	/* We support PHY interrupts routed back to the MAC */
+	for (i = 0; i < PHY_MAX_ADDR; i++)
+		priv->mii_bus->irq[i] = PHY_IGNORE_INTERRUPT;
+
+	ret = mdiobus_register(priv->mii_bus);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to register mii_bus\n");
+		goto out_mdio_irq;
+	}
+
+	ret = nuport_mac_mii_probe(dev);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to probe MII bus\n");
+		goto out_mdio_unregister;
+	}
+
+	ret = register_netdev(dev);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to register net_device\n");
+		goto out_mdio_probe;
+	}
+
+	/* read existing mac address */
+	nuport_mac_read_mac_address(dev);
+
+	dev_info(&pdev->dev, "registered (MAC: %pM)\n", dev->dev_addr);
+
+	return ret;
+
+out_mdio_probe:
+	phy_disconnect(priv->phydev);
+out_mdio_unregister:
+	mdiobus_unregister(priv->mii_bus);
+out_mdio_irq:
+	kfree(priv->mii_bus->irq);
+out_mdio:
+	mdiobus_free(priv->mii_bus);
+out_platform:
+	platform_set_drvdata(pdev, NULL);
+out:
+	clk_put(priv->ephy_clk);
+	clk_put(priv->emac_clk);
+	free_netdev(dev);
+	platform_set_drvdata(pdev, NULL);
+	return ret;
+}
+
+static int nuport_mac_remove(struct platform_device *pdev)
+{
+	struct net_device *dev = platform_get_drvdata(pdev);
+	struct nuport_mac_priv *priv = netdev_priv(dev);
+
+	unregister_netdev(dev);
+	phy_disconnect(priv->phydev);
+	mdiobus_unregister(priv->mii_bus);
+	kfree(priv->mii_bus->irq);
+	mdiobus_free(priv->mii_bus);
+	clk_put(priv->ephy_clk);
+	clk_put(priv->emac_clk);
+	free_netdev(dev);
+
+	platform_set_drvdata(pdev, NULL);
+
+	return 0;
+}
+
+static struct of_device_id nuport_eth_ids[] __initdata = {
+	{.compatible = "moschip,nuport-mac",},
+	{ /* sentinel */ },
+};
+
+static struct platform_driver nuport_eth_driver = {
+	.driver = {
+		.name = "nuport-mac",
+		.owner = THIS_MODULE,
+		.of_match_table = nuport_eth_ids,
+	},
+	.probe	= nuport_mac_probe,
+	.remove	= __devexit_p(nuport_mac_remove),
+};
+
+module_platform_driver(nuport_eth_driver);
+
+MODULE_AUTHOR("Moschip Semiconductors Ltd.");
+MODULE_DESCRIPTION("Moschip MCS8140 Ethernet MAC driver");
+MODULE_LICENSE("GPL");