net: add support for STMicroelectronics Ethernet controllers.

This is the driver for the ST MAC 10/100/1000 on-chip Ethernet
controllers (Synopsys IP blocks).

Driver documentation:
 o http://stlinux.com/drupal/kernel/network/stmmac
Revisions:
 o http://stlinux.com/drupal/kernel/network/stmmac-driver-revisions
Performances:
 o http://stlinux.com/drupal/benchmarks/networking/stmmac

Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/stmmac/stmmac_main.c b/drivers/net/stmmac/stmmac_main.c
new file mode 100644
index 0000000..c2f14dc
--- /dev/null
+++ b/drivers/net/stmmac/stmmac_main.c
@@ -0,0 +1,2204 @@
+/*******************************************************************************
+  This is the driver for the ST MAC 10/100/1000 on-chip Ethernet controllers.
+  ST Ethernet IPs are built around a Synopsys IP Core.
+
+  Copyright (C) 2007-2009  STMicroelectronics Ltd
+
+  This program is free software; you can redistribute it and/or modify it
+  under the terms and conditions of the GNU General Public License,
+  version 2, as published by the Free Software Foundation.
+
+  This program is distributed in the hope it will be useful, but WITHOUT
+  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+  more details.
+
+  You should have received a copy of the GNU General Public License along with
+  this program; if not, write to the Free Software Foundation, Inc.,
+  51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+
+  The full GNU General Public License is included in this distribution in
+  the file called "COPYING".
+
+  Author: Giuseppe Cavallaro <peppe.cavallaro@st.com>
+
+  Documentation available at:
+	http://www.stlinux.com
+  Support available at:
+	https://bugzilla.stlinux.com/
+*******************************************************************************/
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/platform_device.h>
+#include <linux/ip.h>
+#include <linux/tcp.h>
+#include <linux/skbuff.h>
+#include <linux/ethtool.h>
+#include <linux/if_ether.h>
+#include <linux/crc32.h>
+#include <linux/mii.h>
+#include <linux/phy.h>
+#include <linux/if_vlan.h>
+#include <linux/dma-mapping.h>
+#include <linux/stm/soc.h>
+#include "stmmac.h"
+
+#define STMMAC_RESOURCE_NAME	"stmmaceth"
+#define PHY_RESOURCE_NAME	"stmmacphy"
+
+#undef STMMAC_DEBUG
+/*#define STMMAC_DEBUG*/
+#ifdef STMMAC_DEBUG
+#define DBG(nlevel, klevel, fmt, args...) \
+		((void)(netif_msg_##nlevel(priv) && \
+		printk(KERN_##klevel fmt, ## args)))
+#else
+#define DBG(nlevel, klevel, fmt, args...) do { } while (0)
+#endif
+
+#undef STMMAC_RX_DEBUG
+/*#define STMMAC_RX_DEBUG*/
+#ifdef STMMAC_RX_DEBUG
+#define RX_DBG(fmt, args...)  printk(fmt, ## args)
+#else
+#define RX_DBG(fmt, args...)  do { } while (0)
+#endif
+
+#undef STMMAC_XMIT_DEBUG
+/*#define STMMAC_XMIT_DEBUG*/
+#ifdef STMMAC_TX_DEBUG
+#define TX_DBG(fmt, args...)  printk(fmt, ## args)
+#else
+#define TX_DBG(fmt, args...)  do { } while (0)
+#endif
+
+#define STMMAC_ALIGN(x)	L1_CACHE_ALIGN(x)
+#define JUMBO_LEN	9000
+
+/* Module parameters */
+#define TX_TIMEO 5000 /* default 5 seconds */
+static int watchdog = TX_TIMEO;
+module_param(watchdog, int, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(watchdog, "Transmit timeout in milliseconds");
+
+static int debug = -1;		/* -1: default, 0: no output, 16:  all */
+module_param(debug, int, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(debug, "Message Level (0: no output, 16: all)");
+
+static int phyaddr = -1;
+module_param(phyaddr, int, S_IRUGO);
+MODULE_PARM_DESC(phyaddr, "Physical device address");
+
+#define DMA_TX_SIZE 256
+static int dma_txsize = DMA_TX_SIZE;
+module_param(dma_txsize, int, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(dma_txsize, "Number of descriptors in the TX list");
+
+#define DMA_RX_SIZE 256
+static int dma_rxsize = DMA_RX_SIZE;
+module_param(dma_rxsize, int, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(dma_rxsize, "Number of descriptors in the RX list");
+
+static int flow_ctrl = FLOW_OFF;
+module_param(flow_ctrl, int, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(flow_ctrl, "Flow control ability [on/off]");
+
+static int pause = PAUSE_TIME;
+module_param(pause, int, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(pause, "Flow Control Pause Time");
+
+#define TC_DEFAULT 64
+static int tc = TC_DEFAULT;
+module_param(tc, int, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(tc, "DMA threshold control value");
+
+#define RX_NO_COALESCE	1	/* Always interrupt on completion */
+#define TX_NO_COALESCE	-1	/* No moderation by default */
+
+/* Pay attention to tune this parameter; take care of both
+ * hardware capability and network stabitily/performance impact.
+ * Many tests showed that ~4ms latency seems to be good enough. */
+#ifdef CONFIG_STMMAC_TIMER
+#define DEFAULT_PERIODIC_RATE	256
+static int tmrate = DEFAULT_PERIODIC_RATE;
+module_param(tmrate, int, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(tmrate, "External timer freq. (default: 256Hz)");
+#endif
+
+#define DMA_BUFFER_SIZE	BUF_SIZE_2KiB
+static int buf_sz = DMA_BUFFER_SIZE;
+module_param(buf_sz, int, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(buf_sz, "DMA buffer size");
+
+/* In case of Giga ETH, we can enable/disable the COE for the
+ * transmit HW checksum computation.
+ * Note that, if tx csum is off in HW, SG will be still supported. */
+static int tx_coe = HW_CSUM;
+module_param(tx_coe, int, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(tx_coe, "GMAC COE type 2 [on/off]");
+
+static const u32 default_msg_level = (NETIF_MSG_DRV | NETIF_MSG_PROBE |
+				      NETIF_MSG_LINK | NETIF_MSG_IFUP |
+				      NETIF_MSG_IFDOWN | NETIF_MSG_TIMER);
+
+static irqreturn_t stmmac_interrupt(int irq, void *dev_id);
+static netdev_tx_t stmmac_xmit(struct sk_buff *skb, struct net_device *dev);
+
+/**
+ * stmmac_verify_args - verify the driver parameters.
+ * Description: it verifies if some wrong parameter is passed to the driver.
+ * Note that wrong parameters are replaced with the default values.
+ */
+static void stmmac_verify_args(void)
+{
+	if (unlikely(watchdog < 0))
+		watchdog = TX_TIMEO;
+	if (unlikely(dma_rxsize < 0))
+		dma_rxsize = DMA_RX_SIZE;
+	if (unlikely(dma_txsize < 0))
+		dma_txsize = DMA_TX_SIZE;
+	if (unlikely((buf_sz < DMA_BUFFER_SIZE) || (buf_sz > BUF_SIZE_16KiB)))
+		buf_sz = DMA_BUFFER_SIZE;
+	if (unlikely(flow_ctrl > 1))
+		flow_ctrl = FLOW_AUTO;
+	else if (likely(flow_ctrl < 0))
+		flow_ctrl = FLOW_OFF;
+	if (unlikely((pause < 0) || (pause > 0xffff)))
+		pause = PAUSE_TIME;
+
+	return;
+}
+
+#if defined(STMMAC_XMIT_DEBUG) || defined(STMMAC_RX_DEBUG)
+static void print_pkt(unsigned char *buf, int len)
+{
+	int j;
+	pr_info("len = %d byte, buf addr: 0x%p", len, buf);
+	for (j = 0; j < len; j++) {
+		if ((j % 16) == 0)
+			pr_info("\n %03x:", j);
+		pr_info(" %02x", buf[j]);
+	}
+	pr_info("\n");
+	return;
+}
+#endif
+
+/* minimum number of free TX descriptors required to wake up TX process */
+#define STMMAC_TX_THRESH(x)	(x->dma_tx_size/4)
+
+static inline u32 stmmac_tx_avail(struct stmmac_priv *priv)
+{
+	return priv->dirty_tx + priv->dma_tx_size - priv->cur_tx - 1;
+}
+
+/**
+ * stmmac_adjust_link
+ * @dev: net device structure
+ * Description: it adjusts the link parameters.
+ */
+static void stmmac_adjust_link(struct net_device *dev)
+{
+	struct stmmac_priv *priv = netdev_priv(dev);
+	struct phy_device *phydev = priv->phydev;
+	unsigned long ioaddr = dev->base_addr;
+	unsigned long flags;
+	int new_state = 0;
+	unsigned int fc = priv->flow_ctrl, pause_time = priv->pause;
+
+	if (phydev == NULL)
+		return;
+
+	DBG(probe, DEBUG, "stmmac_adjust_link: called.  address %d link %d\n",
+	    phydev->addr, phydev->link);
+
+	spin_lock_irqsave(&priv->lock, flags);
+	if (phydev->link) {
+		u32 ctrl = readl(ioaddr + MAC_CTRL_REG);
+
+		/* Now we make sure that we can be in full duplex mode.
+		 * If not, we operate in half-duplex mode. */
+		if (phydev->duplex != priv->oldduplex) {
+			new_state = 1;
+			if (!(phydev->duplex))
+				ctrl &= ~priv->mac_type->hw.link.duplex;
+			else
+				ctrl |= priv->mac_type->hw.link.duplex;
+			priv->oldduplex = phydev->duplex;
+		}
+		/* Flow Control operation */
+		if (phydev->pause)
+			priv->mac_type->ops->flow_ctrl(ioaddr, phydev->duplex,
+						       fc, pause_time);
+
+		if (phydev->speed != priv->speed) {
+			new_state = 1;
+			switch (phydev->speed) {
+			case 1000:
+				if (likely(priv->is_gmac))
+					ctrl &= ~priv->mac_type->hw.link.port;
+				break;
+			case 100:
+			case 10:
+				if (priv->is_gmac) {
+					ctrl |= priv->mac_type->hw.link.port;
+					if (phydev->speed == SPEED_100) {
+						ctrl |=
+						    priv->mac_type->hw.link.
+						    speed;
+					} else {
+						ctrl &=
+						    ~(priv->mac_type->hw.
+						      link.speed);
+					}
+				} else {
+					ctrl &= ~priv->mac_type->hw.link.port;
+				}
+				priv->fix_mac_speed(priv->bsp_priv,
+						    phydev->speed);
+				break;
+			default:
+				if (netif_msg_link(priv))
+					pr_warning("%s: Speed (%d) is not 10"
+				       " or 100!\n", dev->name, phydev->speed);
+				break;
+			}
+
+			priv->speed = phydev->speed;
+		}
+
+		writel(ctrl, ioaddr + MAC_CTRL_REG);
+
+		if (!priv->oldlink) {
+			new_state = 1;
+			priv->oldlink = 1;
+		}
+	} else if (priv->oldlink) {
+		new_state = 1;
+		priv->oldlink = 0;
+		priv->speed = 0;
+		priv->oldduplex = -1;
+	}
+
+	if (new_state && netif_msg_link(priv))
+		phy_print_status(phydev);
+
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	DBG(probe, DEBUG, "stmmac_adjust_link: exiting\n");
+}
+
+/**
+ * stmmac_init_phy - PHY initialization
+ * @dev: net device structure
+ * Description: it initializes the driver's PHY state, and attaches the PHY
+ * to the mac driver.
+ *  Return value:
+ *  0 on success
+ */
+static int stmmac_init_phy(struct net_device *dev)
+{
+	struct stmmac_priv *priv = netdev_priv(dev);
+	struct phy_device *phydev;
+	char phy_id[BUS_ID_SIZE];	/* PHY to connect */
+	char bus_id[BUS_ID_SIZE];
+
+	priv->oldlink = 0;
+	priv->speed = 0;
+	priv->oldduplex = -1;
+
+	if (priv->phy_addr == -1) {
+		/* We don't have a PHY, so do nothing */
+		return 0;
+	}
+
+	snprintf(bus_id, MII_BUS_ID_SIZE, "%x", priv->bus_id);
+	snprintf(phy_id, BUS_ID_SIZE, PHY_ID_FMT, bus_id, priv->phy_addr);
+	pr_debug("stmmac_init_phy:  trying to attach to %s\n", phy_id);
+
+	phydev = phy_connect(dev, phy_id, &stmmac_adjust_link, 0,
+			priv->phy_interface);
+
+	if (IS_ERR(phydev)) {
+		pr_err("%s: Could not attach to PHY\n", dev->name);
+		return PTR_ERR(phydev);
+	}
+
+	/*
+	 * Broken HW is sometimes missing the pull-up resistor on the
+	 * MDIO line, which results in reads to non-existent devices returning
+	 * 0 rather than 0xffff. Catch this here and treat 0 as a non-existent
+	 * device as well.
+	 * Note: phydev->phy_id is the result of reading the UID PHY registers.
+	 */
+	if (phydev->phy_id == 0) {
+		phy_disconnect(phydev);
+		return -ENODEV;
+	}
+	pr_debug("stmmac_init_phy:  %s: attached to PHY (UID 0x%x)"
+	       " Link = %d\n", dev->name, phydev->phy_id, phydev->link);
+
+	priv->phydev = phydev;
+
+	return 0;
+}
+
+static inline void stmmac_mac_enable_rx(unsigned long ioaddr)
+{
+	u32 value = readl(ioaddr + MAC_CTRL_REG);
+	value |= MAC_RNABLE_RX;
+	/* Set the RE (receive enable bit into the MAC CTRL register).  */
+	writel(value, ioaddr + MAC_CTRL_REG);
+}
+
+static inline void stmmac_mac_enable_tx(unsigned long ioaddr)
+{
+	u32 value = readl(ioaddr + MAC_CTRL_REG);
+	value |= MAC_ENABLE_TX;
+	/* Set the TE (transmit enable bit into the MAC CTRL register).  */
+	writel(value, ioaddr + MAC_CTRL_REG);
+}
+
+static inline void stmmac_mac_disable_rx(unsigned long ioaddr)
+{
+	u32 value = readl(ioaddr + MAC_CTRL_REG);
+	value &= ~MAC_RNABLE_RX;
+	writel(value, ioaddr + MAC_CTRL_REG);
+}
+
+static inline void stmmac_mac_disable_tx(unsigned long ioaddr)
+{
+	u32 value = readl(ioaddr + MAC_CTRL_REG);
+	value &= ~MAC_ENABLE_TX;
+	writel(value, ioaddr + MAC_CTRL_REG);
+}
+
+/**
+ * display_ring
+ * @p: pointer to the ring.
+ * @size: size of the ring.
+ * Description: display all the descriptors within the ring.
+ */
+static void display_ring(struct dma_desc *p, int size)
+{
+	struct tmp_s {
+		u64 a;
+		unsigned int b;
+		unsigned int c;
+	};
+	int i;
+	for (i = 0; i < size; i++) {
+		struct tmp_s *x = (struct tmp_s *)(p + i);
+		pr_info("\t%d [0x%x]: DES0=0x%x DES1=0x%x BUF1=0x%x BUF2=0x%x",
+		       i, (unsigned int)virt_to_phys(&p[i]),
+		       (unsigned int)(x->a), (unsigned int)((x->a) >> 32),
+		       x->b, x->c);
+		pr_info("\n");
+	}
+}
+
+/**
+ * init_dma_desc_rings - init the RX/TX descriptor rings
+ * @dev: net device structure
+ * Description:  this function initializes the DMA RX/TX descriptors
+ * and allocates the socket buffers.
+ */
+static void init_dma_desc_rings(struct net_device *dev)
+{
+	int i;
+	struct stmmac_priv *priv = netdev_priv(dev);
+	struct sk_buff *skb;
+	unsigned int txsize = priv->dma_tx_size;
+	unsigned int rxsize = priv->dma_rx_size;
+	unsigned int bfsize = priv->dma_buf_sz;
+	int buff2_needed = 0;
+	int dis_ic = 0;
+
+#ifdef CONFIG_STMMAC_TIMER
+	/* Using Timers disable interrupts on completion for the reception */
+	dis_ic = 1;
+#endif
+	/* Set the Buffer size according to the MTU;
+	 * indeed, in case of jumbo we need to bump-up the buffer sizes.
+	 */
+	if (unlikely(dev->mtu >= BUF_SIZE_8KiB))
+		bfsize = BUF_SIZE_16KiB;
+	else if (unlikely(dev->mtu >= BUF_SIZE_4KiB))
+		bfsize = BUF_SIZE_8KiB;
+	else if (unlikely(dev->mtu >= BUF_SIZE_2KiB))
+		bfsize = BUF_SIZE_4KiB;
+	else if (unlikely(dev->mtu >= DMA_BUFFER_SIZE))
+		bfsize = BUF_SIZE_2KiB;
+	else
+		bfsize = DMA_BUFFER_SIZE;
+
+	/* If the MTU exceeds 8k so use the second buffer in the chain */
+	if (bfsize >= BUF_SIZE_8KiB)
+		buff2_needed = 1;
+
+	DBG(probe, INFO, "stmmac: txsize %d, rxsize %d, bfsize %d\n",
+	    txsize, rxsize, bfsize);
+
+	priv->rx_skbuff_dma = kmalloc(rxsize * sizeof(dma_addr_t), GFP_KERNEL);
+	priv->rx_skbuff =
+	    kmalloc(sizeof(struct sk_buff *) * rxsize, GFP_KERNEL);
+	priv->dma_rx =
+	    (struct dma_desc *)dma_alloc_coherent(priv->device,
+						  rxsize *
+						  sizeof(struct dma_desc),
+						  &priv->dma_rx_phy,
+						  GFP_KERNEL);
+	priv->tx_skbuff = kmalloc(sizeof(struct sk_buff *) * txsize,
+				       GFP_KERNEL);
+	priv->dma_tx =
+	    (struct dma_desc *)dma_alloc_coherent(priv->device,
+						  txsize *
+						  sizeof(struct dma_desc),
+						  &priv->dma_tx_phy,
+						  GFP_KERNEL);
+
+	if ((priv->dma_rx == NULL) || (priv->dma_tx == NULL)) {
+		pr_err("%s:ERROR allocating the DMA Tx/Rx desc\n", __func__);
+		return;
+	}
+
+	DBG(probe, INFO, "stmmac (%s) DMA desc rings: virt addr (Rx %p, "
+	    "Tx %p)\n\tDMA phy addr (Rx 0x%08x, Tx 0x%08x)\n",
+	    dev->name, priv->dma_rx, priv->dma_tx,
+	    (unsigned int)priv->dma_rx_phy, (unsigned int)priv->dma_tx_phy);
+
+	/* RX INITIALIZATION */
+	DBG(probe, INFO, "stmmac: SKB addresses:\n"
+			 "skb\t\tskb data\tdma data\n");
+
+	for (i = 0; i < rxsize; i++) {
+		struct dma_desc *p = priv->dma_rx + i;
+
+		skb = netdev_alloc_skb_ip_align(dev, bfsize);
+		if (unlikely(skb == NULL)) {
+			pr_err("%s: Rx init fails; skb is NULL\n", __func__);
+			break;
+		}
+		priv->rx_skbuff[i] = skb;
+		priv->rx_skbuff_dma[i] = dma_map_single(priv->device, skb->data,
+						bfsize, DMA_FROM_DEVICE);
+
+		p->des2 = priv->rx_skbuff_dma[i];
+		if (unlikely(buff2_needed))
+			p->des3 = p->des2 + BUF_SIZE_8KiB;
+		DBG(probe, INFO, "[%p]\t[%p]\t[%x]\n", priv->rx_skbuff[i],
+			priv->rx_skbuff[i]->data, priv->rx_skbuff_dma[i]);
+	}
+	priv->cur_rx = 0;
+	priv->dirty_rx = (unsigned int)(i - rxsize);
+	priv->dma_buf_sz = bfsize;
+	buf_sz = bfsize;
+
+	/* TX INITIALIZATION */
+	for (i = 0; i < txsize; i++) {
+		priv->tx_skbuff[i] = NULL;
+		priv->dma_tx[i].des2 = 0;
+	}
+	priv->dirty_tx = 0;
+	priv->cur_tx = 0;
+
+	/* Clear the Rx/Tx descriptors */
+	priv->mac_type->ops->init_rx_desc(priv->dma_rx, rxsize, dis_ic);
+	priv->mac_type->ops->init_tx_desc(priv->dma_tx, txsize);
+
+	if (netif_msg_hw(priv)) {
+		pr_info("RX descriptor ring:\n");
+		display_ring(priv->dma_rx, rxsize);
+		pr_info("TX descriptor ring:\n");
+		display_ring(priv->dma_tx, txsize);
+	}
+	return;
+}
+
+static void dma_free_rx_skbufs(struct stmmac_priv *priv)
+{
+	int i;
+
+	for (i = 0; i < priv->dma_rx_size; i++) {
+		if (priv->rx_skbuff[i]) {
+			dma_unmap_single(priv->device, priv->rx_skbuff_dma[i],
+					 priv->dma_buf_sz, DMA_FROM_DEVICE);
+			dev_kfree_skb_any(priv->rx_skbuff[i]);
+		}
+		priv->rx_skbuff[i] = NULL;
+	}
+	return;
+}
+
+static void dma_free_tx_skbufs(struct stmmac_priv *priv)
+{
+	int i;
+
+	for (i = 0; i < priv->dma_tx_size; i++) {
+		if (priv->tx_skbuff[i] != NULL) {
+			struct dma_desc *p = priv->dma_tx + i;
+			if (p->des2)
+				dma_unmap_single(priv->device, p->des2,
+				 priv->mac_type->ops->get_tx_len(p),
+				 DMA_TO_DEVICE);
+			dev_kfree_skb_any(priv->tx_skbuff[i]);
+			priv->tx_skbuff[i] = NULL;
+		}
+	}
+	return;
+}
+
+static void free_dma_desc_resources(struct stmmac_priv *priv)
+{
+	/* Release the DMA TX/RX socket buffers */
+	dma_free_rx_skbufs(priv);
+	dma_free_tx_skbufs(priv);
+
+	/* Free the region of consistent memory previously allocated for
+	 * the DMA */
+	dma_free_coherent(priv->device,
+			  priv->dma_tx_size * sizeof(struct dma_desc),
+			  priv->dma_tx, priv->dma_tx_phy);
+	dma_free_coherent(priv->device,
+			  priv->dma_rx_size * sizeof(struct dma_desc),
+			  priv->dma_rx, priv->dma_rx_phy);
+	kfree(priv->rx_skbuff_dma);
+	kfree(priv->rx_skbuff);
+	kfree(priv->tx_skbuff);
+
+	return;
+}
+
+/**
+ * stmmac_dma_start_tx
+ * @ioaddr: device I/O address
+ * Description:  this function starts the DMA tx process.
+ */
+static void stmmac_dma_start_tx(unsigned long ioaddr)
+{
+	u32 value = readl(ioaddr + DMA_CONTROL);
+	value |= DMA_CONTROL_ST;
+	writel(value, ioaddr + DMA_CONTROL);
+	return;
+}
+
+static void stmmac_dma_stop_tx(unsigned long ioaddr)
+{
+	u32 value = readl(ioaddr + DMA_CONTROL);
+	value &= ~DMA_CONTROL_ST;
+	writel(value, ioaddr + DMA_CONTROL);
+	return;
+}
+
+/**
+ * stmmac_dma_start_rx
+ * @ioaddr: device I/O address
+ * Description:  this function starts the DMA rx process.
+ */
+static void stmmac_dma_start_rx(unsigned long ioaddr)
+{
+	u32 value = readl(ioaddr + DMA_CONTROL);
+	value |= DMA_CONTROL_SR;
+	writel(value, ioaddr + DMA_CONTROL);
+
+	return;
+}
+
+static void stmmac_dma_stop_rx(unsigned long ioaddr)
+{
+	u32 value = readl(ioaddr + DMA_CONTROL);
+	value &= ~DMA_CONTROL_SR;
+	writel(value, ioaddr + DMA_CONTROL);
+
+	return;
+}
+
+/**
+ *  stmmac_dma_operation_mode - HW DMA operation mode
+ *  @priv : pointer to the private device structure.
+ *  Description: it sets the DMA operation mode: tx/rx DMA thresholds
+ *  or Store-And-Forward capability. It also verifies the COE for the
+ *  transmission in case of Giga ETH.
+ */
+static void stmmac_dma_operation_mode(struct stmmac_priv *priv)
+{
+	if (!priv->is_gmac) {
+		/* MAC 10/100 */
+		priv->mac_type->ops->dma_mode(priv->dev->base_addr, tc, 0);
+		priv->tx_coe = NO_HW_CSUM;
+	} else {
+		if ((priv->dev->mtu <= ETH_DATA_LEN) && (tx_coe)) {
+			priv->mac_type->ops->dma_mode(priv->dev->base_addr,
+						      SF_DMA_MODE, SF_DMA_MODE);
+			tc = SF_DMA_MODE;
+			priv->tx_coe = HW_CSUM;
+		} else {
+			/* Checksum computation is performed in software. */
+			priv->mac_type->ops->dma_mode(priv->dev->base_addr, tc,
+						      SF_DMA_MODE);
+			priv->tx_coe = NO_HW_CSUM;
+		}
+	}
+	tx_coe = priv->tx_coe;
+
+	return;
+}
+
+#ifdef STMMAC_DEBUG
+/**
+ * show_tx_process_state
+ * @status: tx descriptor status field
+ * Description: it shows the Transmit Process State for CSR5[22:20]
+ */
+static void show_tx_process_state(unsigned int status)
+{
+	unsigned int state;
+	state = (status & DMA_STATUS_TS_MASK) >> DMA_STATUS_TS_SHIFT;
+
+	switch (state) {
+	case 0:
+		pr_info("- TX (Stopped): Reset or Stop command\n");
+		break;
+	case 1:
+		pr_info("- TX (Running):Fetching the Tx desc\n");
+		break;
+	case 2:
+		pr_info("- TX (Running): Waiting for end of tx\n");
+		break;
+	case 3:
+		pr_info("- TX (Running): Reading the data "
+		       "and queuing the data into the Tx buf\n");
+		break;
+	case 6:
+		pr_info("- TX (Suspended): Tx Buff Underflow "
+		       "or an unavailable Transmit descriptor\n");
+		break;
+	case 7:
+		pr_info("- TX (Running): Closing Tx descriptor\n");
+		break;
+	default:
+		break;
+	}
+	return;
+}
+
+/**
+ * show_rx_process_state
+ * @status: rx descriptor status field
+ * Description: it shows the  Receive Process State for CSR5[19:17]
+ */
+static void show_rx_process_state(unsigned int status)
+{
+	unsigned int state;
+	state = (status & DMA_STATUS_RS_MASK) >> DMA_STATUS_RS_SHIFT;
+
+	switch (state) {
+	case 0:
+		pr_info("- RX (Stopped): Reset or Stop command\n");
+		break;
+	case 1:
+		pr_info("- RX (Running): Fetching the Rx desc\n");
+		break;
+	case 2:
+		pr_info("- RX (Running):Checking for end of pkt\n");
+		break;
+	case 3:
+		pr_info("- RX (Running): Waiting for Rx pkt\n");
+		break;
+	case 4:
+		pr_info("- RX (Suspended): Unavailable Rx buf\n");
+		break;
+	case 5:
+		pr_info("- RX (Running): Closing Rx descriptor\n");
+		break;
+	case 6:
+		pr_info("- RX(Running): Flushing the current frame"
+		       " from the Rx buf\n");
+		break;
+	case 7:
+		pr_info("- RX (Running): Queuing the Rx frame"
+		       " from the Rx buf into memory\n");
+		break;
+	default:
+		break;
+	}
+	return;
+}
+#endif
+
+/**
+ * stmmac_tx:
+ * @priv: private driver structure
+ * Description: it reclaims resources after transmission completes.
+ */
+static void stmmac_tx(struct stmmac_priv *priv)
+{
+	unsigned int txsize = priv->dma_tx_size;
+	unsigned long ioaddr = priv->dev->base_addr;
+
+	while (priv->dirty_tx != priv->cur_tx) {
+		int last;
+		unsigned int entry = priv->dirty_tx % txsize;
+		struct sk_buff *skb = priv->tx_skbuff[entry];
+		struct dma_desc *p = priv->dma_tx + entry;
+
+		/* Check if the descriptor is owned by the DMA. */
+		if (priv->mac_type->ops->get_tx_owner(p))
+			break;
+
+		/* Verify tx error by looking at the last segment */
+		last = priv->mac_type->ops->get_tx_ls(p);
+		if (likely(last)) {
+			int tx_error =
+			    priv->mac_type->ops->tx_status(&priv->dev->stats,
+							   &priv->xstats,
+							   p, ioaddr);
+			if (likely(tx_error == 0)) {
+				priv->dev->stats.tx_packets++;
+				priv->xstats.tx_pkt_n++;
+			} else
+				priv->dev->stats.tx_errors++;
+		}
+		TX_DBG("%s: curr %d, dirty %d\n", __func__,
+			priv->cur_tx, priv->dirty_tx);
+
+		if (likely(p->des2))
+			dma_unmap_single(priv->device, p->des2,
+					 priv->mac_type->ops->get_tx_len(p),
+					 DMA_TO_DEVICE);
+		if (unlikely(p->des3))
+			p->des3 = 0;
+
+		if (likely(skb != NULL)) {
+			/*
+			 * If there's room in the queue (limit it to size)
+			 * we add this skb back into the pool,
+			 * if it's the right size.
+			 */
+			if ((skb_queue_len(&priv->rx_recycle) <
+				priv->dma_rx_size) &&
+				skb_recycle_check(skb, priv->dma_buf_sz))
+				__skb_queue_head(&priv->rx_recycle, skb);
+			else
+				dev_kfree_skb(skb);
+
+			priv->tx_skbuff[entry] = NULL;
+		}
+
+		priv->mac_type->ops->release_tx_desc(p);
+
+		entry = (++priv->dirty_tx) % txsize;
+	}
+	if (unlikely(netif_queue_stopped(priv->dev) &&
+		     stmmac_tx_avail(priv) > STMMAC_TX_THRESH(priv))) {
+		netif_tx_lock(priv->dev);
+		if (netif_queue_stopped(priv->dev) &&
+		     stmmac_tx_avail(priv) > STMMAC_TX_THRESH(priv)) {
+			TX_DBG("%s: restart transmit\n", __func__);
+			netif_wake_queue(priv->dev);
+		}
+		netif_tx_unlock(priv->dev);
+	}
+	return;
+}
+
+static inline void stmmac_enable_irq(struct stmmac_priv *priv)
+{
+#ifndef CONFIG_STMMAC_TIMER
+	writel(DMA_INTR_DEFAULT_MASK, priv->dev->base_addr + DMA_INTR_ENA);
+#else
+	priv->tm->timer_start(tmrate);
+#endif
+}
+
+static inline void stmmac_disable_irq(struct stmmac_priv *priv)
+{
+#ifndef CONFIG_STMMAC_TIMER
+	writel(0, priv->dev->base_addr + DMA_INTR_ENA);
+#else
+	priv->tm->timer_stop();
+#endif
+}
+
+static int stmmac_has_work(struct stmmac_priv *priv)
+{
+	unsigned int has_work = 0;
+	int rxret, tx_work = 0;
+
+	rxret = priv->mac_type->ops->get_rx_owner(priv->dma_rx +
+		(priv->cur_rx % priv->dma_rx_size));
+
+	if (priv->dirty_tx != priv->cur_tx)
+		tx_work = 1;
+
+	if (likely(!rxret || tx_work))
+		has_work = 1;
+
+	return has_work;
+}
+
+static inline void _stmmac_schedule(struct stmmac_priv *priv)
+{
+	if (likely(stmmac_has_work(priv))) {
+		stmmac_disable_irq(priv);
+		napi_schedule(&priv->napi);
+	}
+}
+
+#ifdef CONFIG_STMMAC_TIMER
+void stmmac_schedule(struct net_device *dev)
+{
+	struct stmmac_priv *priv = netdev_priv(dev);
+
+	priv->xstats.sched_timer_n++;
+
+	_stmmac_schedule(priv);
+
+	return;
+}
+
+static void stmmac_no_timer_started(unsigned int x)
+{;
+};
+
+static void stmmac_no_timer_stopped(void)
+{;
+};
+#endif
+
+/**
+ * stmmac_tx_err:
+ * @priv: pointer to the private device structure
+ * Description: it cleans the descriptors and restarts the transmission
+ * in case of errors.
+ */
+static void stmmac_tx_err(struct stmmac_priv *priv)
+{
+	netif_stop_queue(priv->dev);
+
+	stmmac_dma_stop_tx(priv->dev->base_addr);
+	dma_free_tx_skbufs(priv);
+	priv->mac_type->ops->init_tx_desc(priv->dma_tx, priv->dma_tx_size);
+	priv->dirty_tx = 0;
+	priv->cur_tx = 0;
+	stmmac_dma_start_tx(priv->dev->base_addr);
+
+	priv->dev->stats.tx_errors++;
+	netif_wake_queue(priv->dev);
+
+	return;
+}
+
+/**
+ * stmmac_dma_interrupt - Interrupt handler for the driver
+ * @dev: net device structure
+ * Description: Interrupt handler for the driver (DMA).
+ */
+static void stmmac_dma_interrupt(struct net_device *dev)
+{
+	unsigned long ioaddr = dev->base_addr;
+	struct stmmac_priv *priv = netdev_priv(dev);
+	/* read the status register (CSR5) */
+	u32 intr_status = readl(ioaddr + DMA_STATUS);
+
+	DBG(intr, INFO, "%s: [CSR5: 0x%08x]\n", __func__, intr_status);
+
+#ifdef STMMAC_DEBUG
+	/* It displays the DMA transmit process state (CSR5 register) */
+	if (netif_msg_tx_done(priv))
+		show_tx_process_state(intr_status);
+	if (netif_msg_rx_status(priv))
+		show_rx_process_state(intr_status);
+#endif
+	/* ABNORMAL interrupts */
+	if (unlikely(intr_status & DMA_STATUS_AIS)) {
+		DBG(intr, INFO, "CSR5[15] DMA ABNORMAL IRQ: ");
+		if (unlikely(intr_status & DMA_STATUS_UNF)) {
+			DBG(intr, INFO, "transmit underflow\n");
+			if (unlikely(tc != SF_DMA_MODE)
+			    && (tc <= 256)) {
+				/* Try to bump up the threshold */
+				tc += 64;
+				priv->mac_type->ops->dma_mode(ioaddr, tc,
+					      SF_DMA_MODE);
+				priv->xstats.threshold = tc;
+			}
+			stmmac_tx_err(priv);
+			priv->xstats.tx_undeflow_irq++;
+		}
+		if (unlikely(intr_status & DMA_STATUS_TJT)) {
+			DBG(intr, INFO, "transmit jabber\n");
+			priv->xstats.tx_jabber_irq++;
+		}
+		if (unlikely(intr_status & DMA_STATUS_OVF)) {
+			DBG(intr, INFO, "recv overflow\n");
+			priv->xstats.rx_overflow_irq++;
+		}
+		if (unlikely(intr_status & DMA_STATUS_RU)) {
+			DBG(intr, INFO, "receive buffer unavailable\n");
+			priv->xstats.rx_buf_unav_irq++;
+		}
+		if (unlikely(intr_status & DMA_STATUS_RPS)) {
+			DBG(intr, INFO, "receive process stopped\n");
+			priv->xstats.rx_process_stopped_irq++;
+		}
+		if (unlikely(intr_status & DMA_STATUS_RWT)) {
+			DBG(intr, INFO, "receive watchdog\n");
+			priv->xstats.rx_watchdog_irq++;
+		}
+		if (unlikely(intr_status & DMA_STATUS_ETI)) {
+			DBG(intr, INFO, "transmit early interrupt\n");
+			priv->xstats.tx_early_irq++;
+		}
+		if (unlikely(intr_status & DMA_STATUS_TPS)) {
+			DBG(intr, INFO, "transmit process stopped\n");
+			priv->xstats.tx_process_stopped_irq++;
+			stmmac_tx_err(priv);
+		}
+		if (unlikely(intr_status & DMA_STATUS_FBI)) {
+			DBG(intr, INFO, "fatal bus error\n");
+			priv->xstats.fatal_bus_error_irq++;
+			stmmac_tx_err(priv);
+		}
+	}
+
+	/* TX/RX NORMAL interrupts */
+	if (intr_status & DMA_STATUS_NIS) {
+		priv->xstats.normal_irq_n++;
+		if (likely((intr_status & DMA_STATUS_RI) ||
+			 (intr_status & (DMA_STATUS_TI))))
+				_stmmac_schedule(priv);
+	}
+
+	/* Optional hardware blocks, interrupts should be disabled */
+	if (unlikely(intr_status &
+		     (DMA_STATUS_GPI | DMA_STATUS_GMI | DMA_STATUS_GLI)))
+		pr_info("%s: unexpected status %08x\n", __func__, intr_status);
+
+	/* Clear the interrupt by writing a logic 1 to the CSR5[15-0] */
+	writel((intr_status & 0x1ffff), ioaddr + DMA_STATUS);
+
+	DBG(intr, INFO, "\n\n");
+
+	return;
+}
+
+/**
+ *  stmmac_open - open entry point of the driver
+ *  @dev : pointer to the device structure.
+ *  Description:
+ *  This function is the open entry point of the driver.
+ *  Return value:
+ *  0 on success and an appropriate (-)ve integer as defined in errno.h
+ *  file on failure.
+ */
+static int stmmac_open(struct net_device *dev)
+{
+	struct stmmac_priv *priv = netdev_priv(dev);
+	unsigned long ioaddr = dev->base_addr;
+	int ret;
+
+	/* Check that the MAC address is valid.  If its not, refuse
+	 * to bring the device up. The user must specify an
+	 * address using the following linux command:
+	 *      ifconfig eth0 hw ether xx:xx:xx:xx:xx:xx  */
+	if (!is_valid_ether_addr(dev->dev_addr)) {
+		random_ether_addr(dev->dev_addr);
+		pr_warning("%s: generated random MAC address %pM\n", dev->name,
+			dev->dev_addr);
+	}
+
+	stmmac_verify_args();
+
+	ret = stmmac_init_phy(dev);
+	if (unlikely(ret)) {
+		pr_err("%s: Cannot attach to PHY (error: %d)\n", __func__, ret);
+		return ret;
+	}
+
+	/* Request the IRQ lines */
+	ret = request_irq(dev->irq, &stmmac_interrupt,
+			  IRQF_SHARED, dev->name, dev);
+	if (unlikely(ret < 0)) {
+		pr_err("%s: ERROR: allocating the IRQ %d (error: %d)\n",
+		       __func__, dev->irq, ret);
+		return ret;
+	}
+
+#ifdef CONFIG_STMMAC_TIMER
+	priv->tm = kmalloc(sizeof(struct stmmac_timer *), GFP_KERNEL);
+	if (unlikely(priv->tm == NULL)) {
+		pr_err("%s: ERROR: timer memory alloc failed \n", __func__);
+		return -ENOMEM;
+	}
+	priv->tm->freq = tmrate;
+
+	/* Test if the HW timer can be actually used.
+	 * In case of failure continue with no timer. */
+	if (unlikely((stmmac_open_ext_timer(dev, priv->tm)) < 0)) {
+		pr_warning("stmmaceth: cannot attach the HW timer\n");
+		tmrate = 0;
+		priv->tm->freq = 0;
+		priv->tm->timer_start = stmmac_no_timer_started;
+		priv->tm->timer_stop = stmmac_no_timer_stopped;
+	}
+#endif
+
+	/* Create and initialize the TX/RX descriptors chains. */
+	priv->dma_tx_size = STMMAC_ALIGN(dma_txsize);
+	priv->dma_rx_size = STMMAC_ALIGN(dma_rxsize);
+	priv->dma_buf_sz = STMMAC_ALIGN(buf_sz);
+	init_dma_desc_rings(dev);
+
+	/* DMA initialization and SW reset */
+	if (unlikely(priv->mac_type->ops->dma_init(ioaddr,
+		priv->pbl, priv->dma_tx_phy, priv->dma_rx_phy) < 0)) {
+
+		pr_err("%s: DMA initialization failed\n", __func__);
+		return -1;
+	}
+
+	/* Copy the MAC addr into the HW  */
+	priv->mac_type->ops->set_umac_addr(ioaddr, dev->dev_addr, 0);
+	/* Initialize the MAC Core */
+	priv->mac_type->ops->core_init(ioaddr);
+
+	priv->shutdown = 0;
+
+	/* Initialise the MMC (if present) to disable all interrupts. */
+	writel(0xffffffff, ioaddr + MMC_HIGH_INTR_MASK);
+	writel(0xffffffff, ioaddr + MMC_LOW_INTR_MASK);
+
+	/* Enable the MAC Rx/Tx */
+	stmmac_mac_enable_rx(ioaddr);
+	stmmac_mac_enable_tx(ioaddr);
+
+	/* Set the HW DMA mode and the COE */
+	stmmac_dma_operation_mode(priv);
+
+	/* Extra statistics */
+	memset(&priv->xstats, 0, sizeof(struct stmmac_extra_stats));
+	priv->xstats.threshold = tc;
+
+	/* Start the ball rolling... */
+	DBG(probe, DEBUG, "%s: DMA RX/TX processes started...\n", dev->name);
+	stmmac_dma_start_tx(ioaddr);
+	stmmac_dma_start_rx(ioaddr);
+
+#ifdef CONFIG_STMMAC_TIMER
+	priv->tm->timer_start(tmrate);
+#endif
+	/* Dump DMA/MAC registers */
+	if (netif_msg_hw(priv)) {
+		priv->mac_type->ops->dump_mac_regs(ioaddr);
+		priv->mac_type->ops->dump_dma_regs(ioaddr);
+	}
+
+	if (priv->phydev)
+		phy_start(priv->phydev);
+
+	napi_enable(&priv->napi);
+	skb_queue_head_init(&priv->rx_recycle);
+	netif_start_queue(dev);
+	return 0;
+}
+
+/**
+ *  stmmac_release - close entry point of the driver
+ *  @dev : device pointer.
+ *  Description:
+ *  This is the stop entry point of the driver.
+ */
+static int stmmac_release(struct net_device *dev)
+{
+	struct stmmac_priv *priv = netdev_priv(dev);
+
+	/* Stop and disconnect the PHY */
+	if (priv->phydev) {
+		phy_stop(priv->phydev);
+		phy_disconnect(priv->phydev);
+		priv->phydev = NULL;
+	}
+
+	netif_stop_queue(dev);
+
+#ifdef CONFIG_STMMAC_TIMER
+	/* Stop and release the timer */
+	stmmac_close_ext_timer();
+	if (priv->tm != NULL)
+		kfree(priv->tm);
+#endif
+	napi_disable(&priv->napi);
+	skb_queue_purge(&priv->rx_recycle);
+
+	/* Free the IRQ lines */
+	free_irq(dev->irq, dev);
+
+	/* Stop TX/RX DMA and clear the descriptors */
+	stmmac_dma_stop_tx(dev->base_addr);
+	stmmac_dma_stop_rx(dev->base_addr);
+
+	/* Release and free the Rx/Tx resources */
+	free_dma_desc_resources(priv);
+
+	/* Disable the MAC core */
+	stmmac_mac_disable_tx(dev->base_addr);
+	stmmac_mac_disable_rx(dev->base_addr);
+
+	netif_carrier_off(dev);
+
+	return 0;
+}
+
+/*
+ * To perform emulated hardware segmentation on skb.
+ */
+static int stmmac_sw_tso(struct stmmac_priv *priv, struct sk_buff *skb)
+{
+	struct sk_buff *segs, *curr_skb;
+	int gso_segs = skb_shinfo(skb)->gso_segs;
+
+	/* Estimate the number of fragments in the worst case */
+	if (unlikely(stmmac_tx_avail(priv) < gso_segs)) {
+		netif_stop_queue(priv->dev);
+		TX_DBG(KERN_ERR "%s: TSO BUG! Tx Ring full when queue awake\n",
+		       __func__);
+		if (stmmac_tx_avail(priv) < gso_segs)
+			return NETDEV_TX_BUSY;
+
+		netif_wake_queue(priv->dev);
+	}
+	TX_DBG("\tstmmac_sw_tso: segmenting: skb %p (len %d)\n",
+	       skb, skb->len);
+
+	segs = skb_gso_segment(skb, priv->dev->features & ~NETIF_F_TSO);
+	if (unlikely(IS_ERR(segs)))
+		goto sw_tso_end;
+
+	do {
+		curr_skb = segs;
+		segs = segs->next;
+		TX_DBG("\t\tcurrent skb->len: %d, *curr %p,"
+		       "*next %p\n", curr_skb->len, curr_skb, segs);
+		curr_skb->next = NULL;
+		stmmac_xmit(curr_skb, priv->dev);
+	} while (segs);
+
+sw_tso_end:
+	dev_kfree_skb(skb);
+
+	return NETDEV_TX_OK;
+}
+
+static unsigned int stmmac_handle_jumbo_frames(struct sk_buff *skb,
+					       struct net_device *dev,
+					       int csum_insertion)
+{
+	struct stmmac_priv *priv = netdev_priv(dev);
+	unsigned int nopaged_len = skb_headlen(skb);
+	unsigned int txsize = priv->dma_tx_size;
+	unsigned int entry = priv->cur_tx % txsize;
+	struct dma_desc *desc = priv->dma_tx + entry;
+
+	if (nopaged_len > BUF_SIZE_8KiB) {
+
+		int buf2_size = nopaged_len - BUF_SIZE_8KiB;
+
+		desc->des2 = dma_map_single(priv->device, skb->data,
+					    BUF_SIZE_8KiB, DMA_TO_DEVICE);
+		desc->des3 = desc->des2 + BUF_SIZE_4KiB;
+		priv->mac_type->ops->prepare_tx_desc(desc, 1, BUF_SIZE_8KiB,
+						     csum_insertion);
+
+		entry = (++priv->cur_tx) % txsize;
+		desc = priv->dma_tx + entry;
+
+		desc->des2 = dma_map_single(priv->device,
+					skb->data + BUF_SIZE_8KiB,
+					buf2_size, DMA_TO_DEVICE);
+		desc->des3 = desc->des2 + BUF_SIZE_4KiB;
+		priv->mac_type->ops->prepare_tx_desc(desc, 0,
+						     buf2_size, csum_insertion);
+		priv->mac_type->ops->set_tx_owner(desc);
+		priv->tx_skbuff[entry] = NULL;
+	} else {
+		desc->des2 = dma_map_single(priv->device, skb->data,
+					nopaged_len, DMA_TO_DEVICE);
+		desc->des3 = desc->des2 + BUF_SIZE_4KiB;
+		priv->mac_type->ops->prepare_tx_desc(desc, 1, nopaged_len,
+						     csum_insertion);
+	}
+	return entry;
+}
+
+/**
+ *  stmmac_xmit:
+ *  @skb : the socket buffer
+ *  @dev : device pointer
+ *  Description : Tx entry point of the driver.
+ */
+static netdev_tx_t stmmac_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	struct stmmac_priv *priv = netdev_priv(dev);
+	unsigned int txsize = priv->dma_tx_size;
+	unsigned int entry;
+	int i, csum_insertion = 0;
+	int nfrags = skb_shinfo(skb)->nr_frags;
+	struct dma_desc *desc, *first;
+
+	if (unlikely(stmmac_tx_avail(priv) < nfrags + 1)) {
+		if (!netif_queue_stopped(dev)) {
+			netif_stop_queue(dev);
+			/* This is a hard error, log it. */
+			pr_err("%s: BUG! Tx Ring full when queue awake\n",
+				__func__);
+		}
+		return NETDEV_TX_BUSY;
+	}
+
+	entry = priv->cur_tx % txsize;
+
+#ifdef STMMAC_XMIT_DEBUG
+	if ((skb->len > ETH_FRAME_LEN) || nfrags)
+		pr_info("stmmac xmit:\n"
+		       "\tskb addr %p - len: %d - nopaged_len: %d\n"
+		       "\tn_frags: %d - ip_summed: %d - %s gso\n",
+		       skb, skb->len, skb_headlen(skb), nfrags, skb->ip_summed,
+		       !skb_is_gso(skb) ? "isn't" : "is");
+#endif
+
+	if (unlikely(skb_is_gso(skb)))
+		return stmmac_sw_tso(priv, skb);
+
+	if (likely((skb->ip_summed == CHECKSUM_PARTIAL))) {
+		if (likely(priv->tx_coe == NO_HW_CSUM))
+			skb_checksum_help(skb);
+		else
+			csum_insertion = 1;
+	}
+
+	desc = priv->dma_tx + entry;
+	first = desc;
+
+#ifdef STMMAC_XMIT_DEBUG
+	if ((nfrags > 0) || (skb->len > ETH_FRAME_LEN))
+		pr_debug("stmmac xmit: skb len: %d, nopaged_len: %d,\n"
+		       "\t\tn_frags: %d, ip_summed: %d\n",
+		       skb->len, skb_headlen(skb), nfrags, skb->ip_summed);
+#endif
+	priv->tx_skbuff[entry] = skb;
+	if (unlikely(skb->len >= BUF_SIZE_4KiB)) {
+		entry = stmmac_handle_jumbo_frames(skb, dev, csum_insertion);
+		desc = priv->dma_tx + entry;
+	} else {
+		unsigned int nopaged_len = skb_headlen(skb);
+		desc->des2 = dma_map_single(priv->device, skb->data,
+					nopaged_len, DMA_TO_DEVICE);
+		priv->mac_type->ops->prepare_tx_desc(desc, 1, nopaged_len,
+						     csum_insertion);
+	}
+
+	for (i = 0; i < nfrags; i++) {
+		skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
+		int len = frag->size;
+
+		entry = (++priv->cur_tx) % txsize;
+		desc = priv->dma_tx + entry;
+
+		TX_DBG("\t[entry %d] segment len: %d\n", entry, len);
+		desc->des2 = dma_map_page(priv->device, frag->page,
+					  frag->page_offset,
+					  len, DMA_TO_DEVICE);
+		priv->tx_skbuff[entry] = NULL;
+		priv->mac_type->ops->prepare_tx_desc(desc, 0, len,
+						     csum_insertion);
+		priv->mac_type->ops->set_tx_owner(desc);
+	}
+
+	/* Interrupt on completition only for the latest segment */
+	priv->mac_type->ops->close_tx_desc(desc);
+#ifdef CONFIG_STMMAC_TIMER
+	/* Clean IC while using timers */
+	priv->mac_type->ops->clear_tx_ic(desc);
+#endif
+	/* To avoid raise condition */
+	priv->mac_type->ops->set_tx_owner(first);
+
+	priv->cur_tx++;
+
+#ifdef STMMAC_XMIT_DEBUG
+	if (netif_msg_pktdata(priv)) {
+		pr_info("stmmac xmit: current=%d, dirty=%d, entry=%d, "
+		       "first=%p, nfrags=%d\n",
+		       (priv->cur_tx % txsize), (priv->dirty_tx % txsize),
+		       entry, first, nfrags);
+		display_ring(priv->dma_tx, txsize);
+		pr_info(">>> frame to be transmitted: ");
+		print_pkt(skb->data, skb->len);
+	}
+#endif
+	if (unlikely(stmmac_tx_avail(priv) <= (MAX_SKB_FRAGS + 1))) {
+		TX_DBG("%s: stop transmitted packets\n", __func__);
+		netif_stop_queue(dev);
+	}
+
+	dev->stats.tx_bytes += skb->len;
+
+	/* CSR1 enables the transmit DMA to check for new descriptor */
+	writel(1, dev->base_addr + DMA_XMT_POLL_DEMAND);
+
+	return NETDEV_TX_OK;
+}
+
+static inline void stmmac_rx_refill(struct stmmac_priv *priv)
+{
+	unsigned int rxsize = priv->dma_rx_size;
+	int bfsize = priv->dma_buf_sz;
+	struct dma_desc *p = priv->dma_rx;
+
+	for (; priv->cur_rx - priv->dirty_rx > 0; priv->dirty_rx++) {
+		unsigned int entry = priv->dirty_rx % rxsize;
+		if (likely(priv->rx_skbuff[entry] == NULL)) {
+			struct sk_buff *skb;
+
+			skb = __skb_dequeue(&priv->rx_recycle);
+			if (skb == NULL)
+				skb = netdev_alloc_skb_ip_align(priv->dev,
+								bfsize);
+
+			if (unlikely(skb == NULL))
+				break;
+
+			priv->rx_skbuff[entry] = skb;
+			priv->rx_skbuff_dma[entry] =
+			    dma_map_single(priv->device, skb->data, bfsize,
+					   DMA_FROM_DEVICE);
+
+			(p + entry)->des2 = priv->rx_skbuff_dma[entry];
+			if (unlikely(priv->is_gmac)) {
+				if (bfsize >= BUF_SIZE_8KiB)
+					(p + entry)->des3 =
+					    (p + entry)->des2 + BUF_SIZE_8KiB;
+			}
+			RX_DBG(KERN_INFO "\trefill entry #%d\n", entry);
+		}
+		priv->mac_type->ops->set_rx_owner(p + entry);
+	}
+	return;
+}
+
+static int stmmac_rx(struct stmmac_priv *priv, int limit)
+{
+	unsigned int rxsize = priv->dma_rx_size;
+	unsigned int entry = priv->cur_rx % rxsize;
+	unsigned int next_entry;
+	unsigned int count = 0;
+	struct dma_desc *p = priv->dma_rx + entry;
+	struct dma_desc *p_next;
+
+#ifdef STMMAC_RX_DEBUG
+	if (netif_msg_hw(priv)) {
+		pr_debug(">>> stmmac_rx: descriptor ring:\n");
+		display_ring(priv->dma_rx, rxsize);
+	}
+#endif
+	count = 0;
+	while (!priv->mac_type->ops->get_rx_owner(p)) {
+		int status;
+
+		if (count >= limit)
+			break;
+
+		count++;
+
+		next_entry = (++priv->cur_rx) % rxsize;
+		p_next = priv->dma_rx + next_entry;
+		prefetch(p_next);
+
+		/* read the status of the incoming frame */
+		status = (priv->mac_type->ops->rx_status(&priv->dev->stats,
+							 &priv->xstats, p));
+		if (unlikely(status == discard_frame))
+			priv->dev->stats.rx_errors++;
+		else {
+			struct sk_buff *skb;
+			/* Length should omit the CRC */
+			int frame_len =
+			    priv->mac_type->ops->get_rx_frame_len(p) - 4;
+
+#ifdef STMMAC_RX_DEBUG
+			if (frame_len > ETH_FRAME_LEN)
+				pr_debug("\tRX frame size %d, COE status: %d\n",
+					frame_len, status);
+
+			if (netif_msg_hw(priv))
+				pr_debug("\tdesc: %p [entry %d] buff=0x%x\n",
+					p, entry, p->des2);
+#endif
+			skb = priv->rx_skbuff[entry];
+			if (unlikely(!skb)) {
+				pr_err("%s: Inconsistent Rx descriptor chain\n",
+					priv->dev->name);
+				priv->dev->stats.rx_dropped++;
+				break;
+			}
+			prefetch(skb->data - NET_IP_ALIGN);
+			priv->rx_skbuff[entry] = NULL;
+
+			skb_put(skb, frame_len);
+			dma_unmap_single(priv->device,
+					 priv->rx_skbuff_dma[entry],
+					 priv->dma_buf_sz, DMA_FROM_DEVICE);
+#ifdef STMMAC_RX_DEBUG
+			if (netif_msg_pktdata(priv)) {
+				pr_info(" frame received (%dbytes)", frame_len);
+				print_pkt(skb->data, frame_len);
+			}
+#endif
+			skb->protocol = eth_type_trans(skb, priv->dev);
+
+			if (unlikely(status == csum_none)) {
+				/* always for the old mac 10/100 */
+				skb->ip_summed = CHECKSUM_NONE;
+				netif_receive_skb(skb);
+			} else {
+				skb->ip_summed = CHECKSUM_UNNECESSARY;
+				napi_gro_receive(&priv->napi, skb);
+			}
+
+			priv->dev->stats.rx_packets++;
+			priv->dev->stats.rx_bytes += frame_len;
+			priv->dev->last_rx = jiffies;
+		}
+		entry = next_entry;
+		p = p_next;	/* use prefetched values */
+	}
+
+	stmmac_rx_refill(priv);
+
+	priv->xstats.rx_pkt_n += count;
+
+	return count;
+}
+
+/**
+ *  stmmac_poll - stmmac poll method (NAPI)
+ *  @napi : pointer to the napi structure.
+ *  @budget : maximum number of packets that the current CPU can receive from
+ *	      all interfaces.
+ *  Description :
+ *   This function implements the the reception process.
+ *   Also it runs the TX completion thread
+ */
+static int stmmac_poll(struct napi_struct *napi, int budget)
+{
+	struct stmmac_priv *priv = container_of(napi, struct stmmac_priv, napi);
+	int work_done = 0;
+
+	priv->xstats.poll_n++;
+	stmmac_tx(priv);
+	work_done = stmmac_rx(priv, budget);
+
+	if (work_done < budget) {
+		napi_complete(napi);
+		stmmac_enable_irq(priv);
+	}
+	return work_done;
+}
+
+/**
+ *  stmmac_tx_timeout
+ *  @dev : Pointer to net device structure
+ *  Description: this function is called when a packet transmission fails to
+ *   complete within a reasonable tmrate. The driver will mark the error in the
+ *   netdev structure and arrange for the device to be reset to a sane state
+ *   in order to transmit a new packet.
+ */
+static void stmmac_tx_timeout(struct net_device *dev)
+{
+	struct stmmac_priv *priv = netdev_priv(dev);
+
+	/* Clear Tx resources and restart transmitting again */
+	stmmac_tx_err(priv);
+	return;
+}
+
+/* Configuration changes (passed on by ifconfig) */
+static int stmmac_config(struct net_device *dev, struct ifmap *map)
+{
+	if (dev->flags & IFF_UP)	/* can't act on a running interface */
+		return -EBUSY;
+
+	/* Don't allow changing the I/O address */
+	if (map->base_addr != dev->base_addr) {
+		pr_warning("%s: can't change I/O address\n", dev->name);
+		return -EOPNOTSUPP;
+	}
+
+	/* Don't allow changing the IRQ */
+	if (map->irq != dev->irq) {
+		pr_warning("%s: can't change IRQ number %d\n",
+		       dev->name, dev->irq);
+		return -EOPNOTSUPP;
+	}
+
+	/* ignore other fields */
+	return 0;
+}
+
+/**
+ *  stmmac_multicast_list - entry point for multicast addressing
+ *  @dev : pointer to the device structure
+ *  Description:
+ *  This function is a driver entry point which gets called by the kernel
+ *  whenever multicast addresses must be enabled/disabled.
+ *  Return value:
+ *  void.
+ */
+static void stmmac_multicast_list(struct net_device *dev)
+{
+	struct stmmac_priv *priv = netdev_priv(dev);
+
+	spin_lock(&priv->lock);
+	priv->mac_type->ops->set_filter(dev);
+	spin_unlock(&priv->lock);
+	return;
+}
+
+/**
+ *  stmmac_change_mtu - entry point to change MTU size for the device.
+ *  @dev : device pointer.
+ *  @new_mtu : the new MTU size for the device.
+ *  Description: the Maximum Transfer Unit (MTU) is used by the network layer
+ *  to drive packet transmission. Ethernet has an MTU of 1500 octets
+ *  (ETH_DATA_LEN). This value can be changed with ifconfig.
+ *  Return value:
+ *  0 on success and an appropriate (-)ve integer as defined in errno.h
+ *  file on failure.
+ */
+static int stmmac_change_mtu(struct net_device *dev, int new_mtu)
+{
+	struct stmmac_priv *priv = netdev_priv(dev);
+	int max_mtu;
+
+	if (netif_running(dev)) {
+		pr_err("%s: must be stopped to change its MTU\n", dev->name);
+		return -EBUSY;
+	}
+
+	if (priv->is_gmac)
+		max_mtu = JUMBO_LEN;
+	else
+		max_mtu = ETH_DATA_LEN;
+
+	if ((new_mtu < 46) || (new_mtu > max_mtu)) {
+		pr_err("%s: invalid MTU, max MTU is: %d\n", dev->name, max_mtu);
+		return -EINVAL;
+	}
+
+	dev->mtu = new_mtu;
+
+	return 0;
+}
+
+static irqreturn_t stmmac_interrupt(int irq, void *dev_id)
+{
+	struct net_device *dev = (struct net_device *)dev_id;
+	struct stmmac_priv *priv = netdev_priv(dev);
+
+	if (unlikely(!dev)) {
+		pr_err("%s: invalid dev pointer\n", __func__);
+		return IRQ_NONE;
+	}
+
+	if (priv->is_gmac) {
+		unsigned long ioaddr = dev->base_addr;
+		/* To handle GMAC own interrupts */
+		priv->mac_type->ops->host_irq_status(ioaddr);
+	}
+	stmmac_dma_interrupt(dev);
+
+	return IRQ_HANDLED;
+}
+
+#ifdef CONFIG_NET_POLL_CONTROLLER
+/* Polling receive - used by NETCONSOLE and other diagnostic tools
+ * to allow network I/O with interrupts disabled. */
+static void stmmac_poll_controller(struct net_device *dev)
+{
+	disable_irq(dev->irq);
+	stmmac_interrupt(dev->irq, dev);
+	enable_irq(dev->irq);
+}
+#endif
+
+/**
+ *  stmmac_ioctl - Entry point for the Ioctl
+ *  @dev: Device pointer.
+ *  @rq: An IOCTL specefic structure, that can contain a pointer to
+ *  a proprietary structure used to pass information to the driver.
+ *  @cmd: IOCTL command
+ *  Description:
+ *  Currently there are no special functionality supported in IOCTL, just the
+ *  phy_mii_ioctl(...) can be invoked.
+ */
+static int stmmac_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
+{
+	struct stmmac_priv *priv = netdev_priv(dev);
+	int ret = -EOPNOTSUPP;
+
+	if (!netif_running(dev))
+		return -EINVAL;
+
+	switch (cmd) {
+	case SIOCGMIIPHY:
+	case SIOCGMIIREG:
+	case SIOCSMIIREG:
+		if (!priv->phydev)
+			return -EINVAL;
+
+		spin_lock(&priv->lock);
+		ret = phy_mii_ioctl(priv->phydev, if_mii(rq), cmd);
+		spin_unlock(&priv->lock);
+	default:
+		break;
+	}
+	return ret;
+}
+
+#ifdef STMMAC_VLAN_TAG_USED
+static void stmmac_vlan_rx_register(struct net_device *dev,
+				    struct vlan_group *grp)
+{
+	struct stmmac_priv *priv = netdev_priv(dev);
+
+	DBG(probe, INFO, "%s: Setting vlgrp to %p\n", dev->name, grp);
+
+	spin_lock(&priv->lock);
+	priv->vlgrp = grp;
+	spin_unlock(&priv->lock);
+
+	return;
+}
+#endif
+
+static const struct net_device_ops stmmac_netdev_ops = {
+	.ndo_open = stmmac_open,
+	.ndo_start_xmit = stmmac_xmit,
+	.ndo_stop = stmmac_release,
+	.ndo_change_mtu = stmmac_change_mtu,
+	.ndo_set_multicast_list = stmmac_multicast_list,
+	.ndo_tx_timeout = stmmac_tx_timeout,
+	.ndo_do_ioctl = stmmac_ioctl,
+	.ndo_set_config = stmmac_config,
+#ifdef STMMAC_VLAN_TAG_USED
+	.ndo_vlan_rx_register = stmmac_vlan_rx_register,
+#endif
+#ifdef CONFIG_NET_POLL_CONTROLLER
+	.ndo_poll_controller = stmmac_poll_controller,
+#endif
+	.ndo_set_mac_address = eth_mac_addr,
+};
+
+/**
+ * stmmac_probe - Initialization of the adapter .
+ * @dev : device pointer
+ * Description: The function initializes the network device structure for
+ * the STMMAC driver. It also calls the low level routines
+ * in order to init the HW (i.e. the DMA engine)
+ */
+static int stmmac_probe(struct net_device *dev)
+{
+	int ret = 0;
+	struct stmmac_priv *priv = netdev_priv(dev);
+
+	ether_setup(dev);
+
+	dev->netdev_ops = &stmmac_netdev_ops;
+	stmmac_set_ethtool_ops(dev);
+
+	dev->features |= (NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_HIGHDMA);
+	dev->watchdog_timeo = msecs_to_jiffies(watchdog);
+#ifdef STMMAC_VLAN_TAG_USED
+	/* Both mac100 and gmac support receive VLAN tag detection */
+	dev->features |= NETIF_F_HW_VLAN_RX;
+#endif
+	priv->msg_enable = netif_msg_init(debug, default_msg_level);
+
+	if (priv->is_gmac)
+		priv->rx_csum = 1;
+
+	if (flow_ctrl)
+		priv->flow_ctrl = FLOW_AUTO;	/* RX/TX pause on */
+
+	priv->pause = pause;
+	netif_napi_add(dev, &priv->napi, stmmac_poll, 64);
+
+	/* Get the MAC address */
+	priv->mac_type->ops->get_umac_addr(dev->base_addr, dev->dev_addr, 0);
+
+	if (!is_valid_ether_addr(dev->dev_addr))
+		pr_warning("\tno valid MAC address;"
+			"please, use ifconfig or nwhwconfig!\n");
+
+	ret = register_netdev(dev);
+	if (ret) {
+		pr_err("%s: ERROR %i registering the device\n",
+		       __func__, ret);
+		return -ENODEV;
+	}
+
+	DBG(probe, DEBUG, "%s: Scatter/Gather: %s - HW checksums: %s\n",
+	    dev->name, (dev->features & NETIF_F_SG) ? "on" : "off",
+	    (dev->features & NETIF_F_HW_CSUM) ? "on" : "off");
+
+	spin_lock_init(&priv->lock);
+
+	return ret;
+}
+
+/**
+ * stmmac_mac_device_setup
+ * @dev : device pointer
+ * Description: select and initialise the mac device (mac100 or Gmac).
+ */
+static int stmmac_mac_device_setup(struct net_device *dev)
+{
+	struct stmmac_priv *priv = netdev_priv(dev);
+	unsigned long ioaddr = dev->base_addr;
+
+	struct mac_device_info *device;
+
+	if (priv->is_gmac)
+		device = gmac_setup(ioaddr);
+	else
+		device = mac100_setup(ioaddr);
+
+	if (!device)
+		return -ENOMEM;
+
+	priv->mac_type = device;
+
+	priv->wolenabled = priv->mac_type->hw.pmt;	/* PMT supported */
+	if (priv->wolenabled == PMT_SUPPORTED)
+		priv->wolopts = WAKE_MAGIC;		/* Magic Frame */
+
+	return 0;
+}
+
+static int stmmacphy_dvr_probe(struct platform_device *pdev)
+{
+	struct plat_stmmacphy_data *plat_dat;
+	plat_dat = (struct plat_stmmacphy_data *)((pdev->dev).platform_data);
+
+	pr_debug("stmmacphy_dvr_probe: added phy for bus %d\n",
+	       plat_dat->bus_id);
+
+	return 0;
+}
+
+static int stmmacphy_dvr_remove(struct platform_device *pdev)
+{
+	return 0;
+}
+
+static struct platform_driver stmmacphy_driver = {
+	.driver = {
+		   .name = PHY_RESOURCE_NAME,
+		   },
+	.probe = stmmacphy_dvr_probe,
+	.remove = stmmacphy_dvr_remove,
+};
+
+/**
+ * stmmac_associate_phy
+ * @dev: pointer to device structure
+ * @data: points to the private structure.
+ * Description: Scans through all the PHYs we have registered and checks if
+ * any are associated with our MAC.  If so, then just fill in
+ * the blanks in our local context structure
+ */
+static int stmmac_associate_phy(struct device *dev, void *data)
+{
+	struct stmmac_priv *priv = (struct stmmac_priv *)data;
+	struct plat_stmmacphy_data *plat_dat;
+
+	plat_dat = (struct plat_stmmacphy_data *)(dev->platform_data);
+
+	DBG(probe, DEBUG, "%s: checking phy for bus %d\n", __func__,
+		plat_dat->bus_id);
+
+	/* Check that this phy is for the MAC being initialised */
+	if (priv->bus_id != plat_dat->bus_id)
+		return 0;
+
+	/* OK, this PHY is connected to the MAC.
+	   Go ahead and get the parameters */
+	DBG(probe, DEBUG, "%s: OK. Found PHY config\n", __func__);
+	priv->phy_irq =
+	    platform_get_irq_byname(to_platform_device(dev), "phyirq");
+	DBG(probe, DEBUG, "%s: PHY irq on bus %d is %d\n", __func__,
+	    plat_dat->bus_id, priv->phy_irq);
+
+	/* Override with kernel parameters if supplied XXX CRS XXX
+	 * this needs to have multiple instances */
+	if ((phyaddr >= 0) && (phyaddr <= 31))
+		plat_dat->phy_addr = phyaddr;
+
+	priv->phy_addr = plat_dat->phy_addr;
+	priv->phy_mask = plat_dat->phy_mask;
+	priv->phy_interface = plat_dat->interface;
+	priv->phy_reset = plat_dat->phy_reset;
+
+	DBG(probe, DEBUG, "%s: exiting\n", __func__);
+	return 1;	/* forces exit of driver_for_each_device() */
+}
+
+/**
+ * stmmac_dvr_probe
+ * @pdev: platform device pointer
+ * Description: the driver is initialized through platform_device.
+ */
+static int stmmac_dvr_probe(struct platform_device *pdev)
+{
+	int ret = 0;
+	struct resource *res;
+	unsigned int *addr = NULL;
+	struct net_device *ndev = NULL;
+	struct stmmac_priv *priv;
+	struct plat_stmmacenet_data *plat_dat;
+
+	pr_info("STMMAC driver:\n\tplatform registration... ");
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		ret = -ENODEV;
+		goto out;
+	}
+	pr_info("done!\n");
+
+	if (!request_mem_region(res->start, (res->end - res->start),
+				pdev->name)) {
+		pr_err("%s: ERROR: memory allocation failed"
+		       "cannot get the I/O addr 0x%x\n",
+		       __func__, (unsigned int)res->start);
+		ret = -EBUSY;
+		goto out;
+	}
+
+	addr = ioremap(res->start, (res->end - res->start));
+	if (!addr) {
+		pr_err("%s: ERROR: memory mapping failed \n", __func__);
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	ndev = alloc_etherdev(sizeof(struct stmmac_priv));
+	if (!ndev) {
+		pr_err("%s: ERROR: allocating the device\n", __func__);
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	SET_NETDEV_DEV(ndev, &pdev->dev);
+
+	/* Get the MAC information */
+	ndev->irq = platform_get_irq_byname(pdev, "macirq");
+	if (ndev->irq == -ENXIO) {
+		pr_err("%s: ERROR: MAC IRQ configuration "
+		       "information not found\n", __func__);
+		ret = -ENODEV;
+		goto out;
+	}
+
+	priv = netdev_priv(ndev);
+	priv->device = &(pdev->dev);
+	priv->dev = ndev;
+	plat_dat = (struct plat_stmmacenet_data *)((pdev->dev).platform_data);
+	priv->bus_id = plat_dat->bus_id;
+	priv->pbl = plat_dat->pbl;	/* TLI */
+	priv->is_gmac = plat_dat->has_gmac;	/* GMAC is on board */
+
+	platform_set_drvdata(pdev, ndev);
+
+	/* Set the I/O base addr */
+	ndev->base_addr = (unsigned long)addr;
+
+	/* MAC HW revice detection */
+	ret = stmmac_mac_device_setup(ndev);
+	if (ret < 0)
+		goto out;
+
+	/* Network Device Registration */
+	ret = stmmac_probe(ndev);
+	if (ret < 0)
+		goto out;
+
+	/* associate a PHY - it is provided by another platform bus */
+	if (!driver_for_each_device
+	    (&(stmmacphy_driver.driver), NULL, (void *)priv,
+	     stmmac_associate_phy)) {
+		pr_err("No PHY device is associated with this MAC!\n");
+		ret = -ENODEV;
+		goto out;
+	}
+
+	priv->fix_mac_speed = plat_dat->fix_mac_speed;
+	priv->bsp_priv = plat_dat->bsp_priv;
+
+	pr_info("\t%s - (dev. name: %s - id: %d, IRQ #%d\n"
+	       "\tIO base addr: 0x%08x)\n", ndev->name, pdev->name,
+	       pdev->id, ndev->irq, (unsigned int)addr);
+
+	/* MDIO bus Registration */
+	pr_debug("\tMDIO bus (id: %d)...", priv->bus_id);
+	ret = stmmac_mdio_register(ndev);
+	if (ret < 0)
+		goto out;
+	pr_debug("registered!\n");
+
+out:
+	if (ret < 0) {
+		platform_set_drvdata(pdev, NULL);
+		release_mem_region(res->start, (res->end - res->start));
+		if (addr != NULL)
+			iounmap(addr);
+	}
+
+	return ret;
+}
+
+/**
+ * stmmac_dvr_remove
+ * @pdev: platform device pointer
+ * Description: this function resets the TX/RX processes, disables the MAC RX/TX
+ * changes the link status, releases the DMA descriptor rings,
+ * unregisters the MDIO bus and unmaps the allocated memory.
+ */
+static int stmmac_dvr_remove(struct platform_device *pdev)
+{
+	struct net_device *ndev = platform_get_drvdata(pdev);
+	struct resource *res;
+
+	pr_info("%s:\n\tremoving driver", __func__);
+
+	stmmac_dma_stop_rx(ndev->base_addr);
+	stmmac_dma_stop_tx(ndev->base_addr);
+
+	stmmac_mac_disable_rx(ndev->base_addr);
+	stmmac_mac_disable_tx(ndev->base_addr);
+
+	netif_carrier_off(ndev);
+
+	stmmac_mdio_unregister(ndev);
+
+	platform_set_drvdata(pdev, NULL);
+	unregister_netdev(ndev);
+
+	iounmap((void *)ndev->base_addr);
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	release_mem_region(res->start, (res->end - res->start));
+
+	free_netdev(ndev);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM
+static int stmmac_suspend(struct platform_device *pdev, pm_message_t state)
+{
+	struct net_device *dev = platform_get_drvdata(pdev);
+	struct stmmac_priv *priv = netdev_priv(dev);
+	int dis_ic = 0;
+
+	if (!dev || !netif_running(dev))
+		return 0;
+
+	spin_lock(&priv->lock);
+
+	if (state.event == PM_EVENT_SUSPEND) {
+		netif_device_detach(dev);
+		netif_stop_queue(dev);
+		if (priv->phydev)
+			phy_stop(priv->phydev);
+
+#ifdef CONFIG_STMMAC_TIMER
+		priv->tm->timer_stop();
+		dis_ic = 1;
+#endif
+		napi_disable(&priv->napi);
+
+		/* Stop TX/RX DMA */
+		stmmac_dma_stop_tx(dev->base_addr);
+		stmmac_dma_stop_rx(dev->base_addr);
+		/* Clear the Rx/Tx descriptors */
+		priv->mac_type->ops->init_rx_desc(priv->dma_rx,
+						  priv->dma_rx_size, dis_ic);
+		priv->mac_type->ops->init_tx_desc(priv->dma_tx,
+						  priv->dma_tx_size);
+
+		stmmac_mac_disable_tx(dev->base_addr);
+
+		if (device_may_wakeup(&(pdev->dev))) {
+			/* Enable Power down mode by programming the PMT regs */
+			if (priv->wolenabled == PMT_SUPPORTED)
+				priv->mac_type->ops->pmt(dev->base_addr,
+							 priv->wolopts);
+		} else {
+			stmmac_mac_disable_rx(dev->base_addr);
+		}
+	} else {
+		priv->shutdown = 1;
+		/* Although this can appear slightly redundant it actually
+		 * makes fast the standby operation and guarantees the driver
+		 * working if hibernation is on media. */
+		stmmac_release(dev);
+	}
+
+	spin_unlock(&priv->lock);
+	return 0;
+}
+
+static int stmmac_resume(struct platform_device *pdev)
+{
+	struct net_device *dev = platform_get_drvdata(pdev);
+	struct stmmac_priv *priv = netdev_priv(dev);
+	unsigned long ioaddr = dev->base_addr;
+
+	if (!netif_running(dev))
+		return 0;
+
+	spin_lock(&priv->lock);
+
+	if (priv->shutdown) {
+		/* Re-open the interface and re-init the MAC/DMA
+		   and the rings. */
+		stmmac_open(dev);
+		goto out_resume;
+	}
+
+	/* Power Down bit, into the PM register, is cleared
+	 * automatically as soon as a magic packet or a Wake-up frame
+	 * is received. Anyway, it's better to manually clear
+	 * this bit because it can generate problems while resuming
+	 * from another devices (e.g. serial console). */
+	if (device_may_wakeup(&(pdev->dev)))
+		if (priv->wolenabled == PMT_SUPPORTED)
+			priv->mac_type->ops->pmt(dev->base_addr, 0);
+
+	netif_device_attach(dev);
+
+	/* Enable the MAC and DMA */
+	stmmac_mac_enable_rx(ioaddr);
+	stmmac_mac_enable_tx(ioaddr);
+	stmmac_dma_start_tx(ioaddr);
+	stmmac_dma_start_rx(ioaddr);
+
+#ifdef CONFIG_STMMAC_TIMER
+	priv->tm->timer_start(tmrate);
+#endif
+	napi_enable(&priv->napi);
+
+	if (priv->phydev)
+		phy_start(priv->phydev);
+
+	netif_start_queue(dev);
+
+out_resume:
+	spin_unlock(&priv->lock);
+	return 0;
+}
+#endif
+
+static struct platform_driver stmmac_driver = {
+	.driver = {
+		   .name = STMMAC_RESOURCE_NAME,
+		   },
+	.probe = stmmac_dvr_probe,
+	.remove = stmmac_dvr_remove,
+#ifdef CONFIG_PM
+	.suspend = stmmac_suspend,
+	.resume = stmmac_resume,
+#endif
+
+};
+
+/**
+ * stmmac_init_module - Entry point for the driver
+ * Description: This function is the entry point for the driver.
+ */
+static int __init stmmac_init_module(void)
+{
+	int ret;
+
+	if (platform_driver_register(&stmmacphy_driver)) {
+		pr_err("No PHY devices registered!\n");
+		return -ENODEV;
+	}
+
+	ret = platform_driver_register(&stmmac_driver);
+	return ret;
+}
+
+/**
+ * stmmac_cleanup_module - Cleanup routine for the driver
+ * Description: This function is the cleanup routine for the driver.
+ */
+static void __exit stmmac_cleanup_module(void)
+{
+	platform_driver_unregister(&stmmacphy_driver);
+	platform_driver_unregister(&stmmac_driver);
+}
+
+#ifndef MODULE
+static int __init stmmac_cmdline_opt(char *str)
+{
+	char *opt;
+
+	if (!str || !*str)
+		return -EINVAL;
+	while ((opt = strsep(&str, ",")) != NULL) {
+		if (!strncmp(opt, "debug:", 6))
+			strict_strtoul(opt + 6, 0, (unsigned long *)&debug);
+		else if (!strncmp(opt, "phyaddr:", 8))
+			strict_strtoul(opt + 8, 0, (unsigned long *)&phyaddr);
+		else if (!strncmp(opt, "dma_txsize:", 11))
+			strict_strtoul(opt + 11, 0,
+				       (unsigned long *)&dma_txsize);
+		else if (!strncmp(opt, "dma_rxsize:", 11))
+			strict_strtoul(opt + 11, 0,
+				       (unsigned long *)&dma_rxsize);
+		else if (!strncmp(opt, "buf_sz:", 7))
+			strict_strtoul(opt + 7, 0, (unsigned long *)&buf_sz);
+		else if (!strncmp(opt, "tc:", 3))
+			strict_strtoul(opt + 3, 0, (unsigned long *)&tc);
+		else if (!strncmp(opt, "tx_coe:", 7))
+			strict_strtoul(opt + 7, 0, (unsigned long *)&tx_coe);
+		else if (!strncmp(opt, "watchdog:", 9))
+			strict_strtoul(opt + 9, 0, (unsigned long *)&watchdog);
+		else if (!strncmp(opt, "flow_ctrl:", 10))
+			strict_strtoul(opt + 10, 0,
+				       (unsigned long *)&flow_ctrl);
+		else if (!strncmp(opt, "pause:", 6))
+			strict_strtoul(opt + 6, 0, (unsigned long *)&pause);
+#ifdef CONFIG_STMMAC_TIMER
+		else if (!strncmp(opt, "tmrate:", 7))
+			strict_strtoul(opt + 7, 0, (unsigned long *)&tmrate);
+#endif
+	}
+	return 0;
+}
+
+__setup("stmmaceth=", stmmac_cmdline_opt);
+#endif
+
+module_init(stmmac_init_module);
+module_exit(stmmac_cleanup_module);
+
+MODULE_DESCRIPTION("STMMAC 10/100/1000 Ethernet driver");
+MODULE_AUTHOR("Giuseppe Cavallaro <peppe.cavallaro@st.com>");
+MODULE_LICENSE("GPL");