diff mbox

[v7] net: ethernet: add driver for Aurora VLSI NB8800 Ethernet controller

Message ID 1447867764-23075-1-git-send-email-mans@mansr.com
State Changes Requested, archived
Delegated to: David Miller
Headers show

Commit Message

Måns Rullgård Nov. 18, 2015, 5:29 p.m. UTC
This adds a driver for the Aurora VLSI NB8800 Ethernet controller.
It is an almost complete rewrite of a driver originally found in
a Sigma Designs 2.6.22 tree.

Signed-off-by: Mans Rullgard <mans@mansr.com>
---
Changes:
- fix int / unsigned int mismatch
- spell out "unsigned int"
---
 drivers/net/ethernet/Kconfig         |    1 +
 drivers/net/ethernet/Makefile        |    1 +
 drivers/net/ethernet/aurora/Kconfig  |   20 +
 drivers/net/ethernet/aurora/Makefile |    1 +
 drivers/net/ethernet/aurora/nb8800.c | 1552 ++++++++++++++++++++++++++++++++++
 drivers/net/ethernet/aurora/nb8800.h |  316 +++++++
 6 files changed, 1891 insertions(+)
 create mode 100644 drivers/net/ethernet/aurora/Kconfig
 create mode 100644 drivers/net/ethernet/aurora/Makefile
 create mode 100644 drivers/net/ethernet/aurora/nb8800.c
 create mode 100644 drivers/net/ethernet/aurora/nb8800.h

Comments

David Miller Nov. 19, 2015, 4:01 a.m. UTC | #1
From: Mans Rullgard <mans@mansr.com>
Date: Wed, 18 Nov 2015 17:29:24 +0000

> +static int nb8800_poll(struct napi_struct *napi, int budget)
> +{
> +	struct net_device *dev = napi->dev;
> +	struct nb8800_priv *priv = netdev_priv(dev);
> +	struct nb8800_rx_desc *rxd;
> +	int work = 0;
> +	int last = priv->rx_eoc;
> +	int next;
 ...
> +		next = (last + 1) % RX_DESC_COUNT;

You should look at what the assembler looks like for these modulo
operations.

They will be much simpler (ie. one instruction) if you use unsigned
variables to hold the queue indices.

Please fix this in the entire driver.
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
diff mbox

Patch

diff --git a/drivers/net/ethernet/Kconfig b/drivers/net/ethernet/Kconfig
index 05aa759..8310163 100644
--- a/drivers/net/ethernet/Kconfig
+++ b/drivers/net/ethernet/Kconfig
@@ -29,6 +29,7 @@  source "drivers/net/ethernet/apm/Kconfig"
 source "drivers/net/ethernet/apple/Kconfig"
 source "drivers/net/ethernet/arc/Kconfig"
 source "drivers/net/ethernet/atheros/Kconfig"
+source "drivers/net/ethernet/aurora/Kconfig"
 source "drivers/net/ethernet/cadence/Kconfig"
 source "drivers/net/ethernet/adi/Kconfig"
 source "drivers/net/ethernet/broadcom/Kconfig"
diff --git a/drivers/net/ethernet/Makefile b/drivers/net/ethernet/Makefile
index ddfc808..b435fb0 100644
--- a/drivers/net/ethernet/Makefile
+++ b/drivers/net/ethernet/Makefile
@@ -15,6 +15,7 @@  obj-$(CONFIG_NET_XGENE) += apm/
 obj-$(CONFIG_NET_VENDOR_APPLE) += apple/
 obj-$(CONFIG_NET_VENDOR_ARC) += arc/
 obj-$(CONFIG_NET_VENDOR_ATHEROS) += atheros/
+obj-$(CONFIG_NET_VENDOR_AURORA) += aurora/
 obj-$(CONFIG_NET_CADENCE) += cadence/
 obj-$(CONFIG_NET_BFIN) += adi/
 obj-$(CONFIG_NET_VENDOR_BROADCOM) += broadcom/
diff --git a/drivers/net/ethernet/aurora/Kconfig b/drivers/net/ethernet/aurora/Kconfig
new file mode 100644
index 0000000..a3c7106
--- /dev/null
+++ b/drivers/net/ethernet/aurora/Kconfig
@@ -0,0 +1,20 @@ 
+config NET_VENDOR_AURORA
+	bool "Aurora VLSI devices"
+	help
+	  If you have a network (Ethernet) device belonging to this class,
+	  say Y.
+
+	  Note that the answer to this question doesn't directly affect the
+	  kernel: saying N will just cause the configurator to skip all
+	  questions about Aurora devices. If you say Y, you will be asked
+	  for your specific device in the following questions.
+
+if NET_VENDOR_AURORA
+
+config AURORA_NB8800
+	tristate "Aurora AU-NB8800 support"
+	select PHYLIB
+	help
+	 Support for the AU-NB8800 gigabit Ethernet controller.
+
+endif
diff --git a/drivers/net/ethernet/aurora/Makefile b/drivers/net/ethernet/aurora/Makefile
new file mode 100644
index 0000000..6cb528a
--- /dev/null
+++ b/drivers/net/ethernet/aurora/Makefile
@@ -0,0 +1 @@ 
+obj-$(CONFIG_AURORA_NB8800) += nb8800.o
diff --git a/drivers/net/ethernet/aurora/nb8800.c b/drivers/net/ethernet/aurora/nb8800.c
new file mode 100644
index 0000000..c55d000
--- /dev/null
+++ b/drivers/net/ethernet/aurora/nb8800.c
@@ -0,0 +1,1552 @@ 
+/*
+ * Copyright (C) 2015 Mans Rullgard <mans@mansr.com>
+ *
+ * Mostly rewritten, based on driver from Sigma Designs.  Original
+ * copyright notice below.
+ *
+ *
+ * Driver for tangox SMP864x/SMP865x/SMP867x/SMP868x builtin Ethernet Mac.
+ *
+ * Copyright (C) 2005 Maxime Bizon <mbizon@freebox.fr>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that 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.
+ */
+
+#include <linux/module.h>
+#include <linux/etherdevice.h>
+#include <linux/delay.h>
+#include <linux/ethtool.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/of_device.h>
+#include <linux/of_mdio.h>
+#include <linux/of_net.h>
+#include <linux/dma-mapping.h>
+#include <linux/phy.h>
+#include <linux/cache.h>
+#include <linux/jiffies.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <asm/barrier.h>
+
+#include "nb8800.h"
+
+static void nb8800_tx_done(struct net_device *dev);
+static int nb8800_dma_stop(struct net_device *dev);
+
+static inline u8 nb8800_readb(struct nb8800_priv *priv, int reg)
+{
+	return readb(priv->base + reg);
+}
+
+static inline u32 nb8800_readl(struct nb8800_priv *priv, int reg)
+{
+	return readl(priv->base + reg);
+}
+
+static inline void nb8800_writeb(struct nb8800_priv *priv, int reg, u8 val)
+{
+	writeb(val, priv->base + reg);
+}
+
+static inline void nb8800_writew(struct nb8800_priv *priv, int reg, u16 val)
+{
+	writew(val, priv->base + reg);
+}
+
+static inline void nb8800_writel(struct nb8800_priv *priv, int reg, u32 val)
+{
+	writel(val, priv->base + reg);
+}
+
+static inline void nb8800_maskb(struct nb8800_priv *priv, int reg,
+				u32 mask, u32 val)
+{
+	u32 old = nb8800_readb(priv, reg);
+	u32 new = (old & ~mask) | (val & mask);
+
+	if (new != old)
+		nb8800_writeb(priv, reg, new);
+}
+
+static inline void nb8800_maskl(struct nb8800_priv *priv, int reg,
+				u32 mask, u32 val)
+{
+	u32 old = nb8800_readl(priv, reg);
+	u32 new = (old & ~mask) | (val & mask);
+
+	if (new != old)
+		nb8800_writel(priv, reg, new);
+}
+
+static inline void nb8800_modb(struct nb8800_priv *priv, int reg, u8 bits,
+			       bool set)
+{
+	nb8800_maskb(priv, reg, bits, set ? bits : 0);
+}
+
+static inline void nb8800_setb(struct nb8800_priv *priv, int reg, u8 bits)
+{
+	nb8800_maskb(priv, reg, bits, bits);
+}
+
+static inline void nb8800_clearb(struct nb8800_priv *priv, int reg, u8 bits)
+{
+	nb8800_maskb(priv, reg, bits, 0);
+}
+
+static inline void nb8800_modl(struct nb8800_priv *priv, int reg, u32 bits,
+			       bool set)
+{
+	nb8800_maskl(priv, reg, bits, set ? bits : 0);
+}
+
+static inline void nb8800_setl(struct nb8800_priv *priv, int reg, u32 bits)
+{
+	nb8800_maskl(priv, reg, bits, bits);
+}
+
+static inline void nb8800_clearl(struct nb8800_priv *priv, int reg, u32 bits)
+{
+	nb8800_maskl(priv, reg, bits, 0);
+}
+
+static int nb8800_mdio_wait(struct mii_bus *bus)
+{
+	struct nb8800_priv *priv = bus->priv;
+	u32 val;
+
+	return readl_poll_timeout_atomic(priv->base + NB8800_MDIO_CMD,
+					 val, !(val & MDIO_CMD_GO), 1, 1000);
+}
+
+static int nb8800_mdio_cmd(struct mii_bus *bus, u32 cmd)
+{
+	struct nb8800_priv *priv = bus->priv;
+	int err;
+
+	err = nb8800_mdio_wait(bus);
+	if (err)
+		return err;
+
+	nb8800_writel(priv, NB8800_MDIO_CMD, cmd);
+	udelay(10);
+	nb8800_writel(priv, NB8800_MDIO_CMD, cmd | MDIO_CMD_GO);
+
+	return nb8800_mdio_wait(bus);
+}
+
+static int nb8800_mdio_read(struct mii_bus *bus, int phy_id, int reg)
+{
+	struct nb8800_priv *priv = bus->priv;
+	u32 val;
+	int err;
+
+	err = nb8800_mdio_cmd(bus, MDIO_CMD_ADDR(phy_id) | MDIO_CMD_REG(reg));
+	if (err)
+		return err;
+
+	val = nb8800_readl(priv, NB8800_MDIO_STS);
+	if (val & MDIO_STS_ERR)
+		return 0xffff;
+
+	return val & 0xffff;
+}
+
+static int nb8800_mdio_write(struct mii_bus *bus, int phy_id, int reg, u16 val)
+{
+	u32 cmd = MDIO_CMD_ADDR(phy_id) | MDIO_CMD_REG(reg) |
+		MDIO_CMD_DATA(val) | MDIO_CMD_WR;
+
+	return nb8800_mdio_cmd(bus, cmd);
+}
+
+static void nb8800_mac_tx(struct net_device *dev, bool enable)
+{
+	struct nb8800_priv *priv = netdev_priv(dev);
+
+	while (nb8800_readl(priv, NB8800_TXC_CR) & TCR_EN)
+		cpu_relax();
+
+	nb8800_modb(priv, NB8800_TX_CTL1, TX_EN, enable);
+}
+
+static void nb8800_mac_rx(struct net_device *dev, bool enable)
+{
+	nb8800_modb(netdev_priv(dev), NB8800_RX_CTL, RX_EN, enable);
+}
+
+static void nb8800_mac_af(struct net_device *dev, bool enable)
+{
+	nb8800_modb(netdev_priv(dev), NB8800_RX_CTL, RX_AF_EN, enable);
+}
+
+static void nb8800_start_rx(struct net_device *dev)
+{
+	nb8800_setl(netdev_priv(dev), NB8800_RXC_CR, RCR_EN);
+}
+
+static int nb8800_alloc_rx(struct net_device *dev, unsigned int i, bool napi)
+{
+	struct nb8800_priv *priv = netdev_priv(dev);
+	struct nb8800_rx_desc *rxd = &priv->rx_descs[i];
+	struct nb8800_rx_buf *rxb = &priv->rx_bufs[i];
+	int size = L1_CACHE_ALIGN(RX_BUF_SIZE);
+	dma_addr_t dma_addr;
+	struct page *page;
+	unsigned long offset;
+	void *data;
+
+	data = napi ? napi_alloc_frag(size) : netdev_alloc_frag(size);
+	if (!data)
+		return -ENOMEM;
+
+	page = virt_to_head_page(data);
+	offset = data - page_address(page);
+
+	dma_addr = dma_map_page(&dev->dev, page, offset, RX_BUF_SIZE,
+				DMA_FROM_DEVICE);
+
+	if (dma_mapping_error(&dev->dev, dma_addr)) {
+		skb_free_frag(data);
+		return -ENOMEM;
+	}
+
+	rxb->page = page;
+	rxb->offset = offset;
+	rxd->desc.s_addr = dma_addr;
+
+	return 0;
+}
+
+static void nb8800_receive(struct net_device *dev, unsigned int i,
+			   unsigned int len)
+{
+	struct nb8800_priv *priv = netdev_priv(dev);
+	struct nb8800_rx_desc *rxd = &priv->rx_descs[i];
+	struct page *page = priv->rx_bufs[i].page;
+	int offset = priv->rx_bufs[i].offset;
+	void *data = page_address(page) + offset;
+	dma_addr_t dma = rxd->desc.s_addr;
+	struct sk_buff *skb;
+	unsigned int size;
+	int err;
+
+	size = len <= RX_COPYBREAK ? len : RX_COPYHDR;
+
+	skb = napi_alloc_skb(&priv->napi, size);
+	if (!skb) {
+		netdev_err(dev, "rx skb allocation failed\n");
+		dev->stats.rx_dropped++;
+		return;
+	}
+
+	if (len <= RX_COPYBREAK) {
+		dma_sync_single_for_cpu(&dev->dev, dma, len, DMA_FROM_DEVICE);
+		memcpy(skb_put(skb, len), data, len);
+		dma_sync_single_for_device(&dev->dev, dma, len,
+					   DMA_FROM_DEVICE);
+	} else {
+		err = nb8800_alloc_rx(dev, i, true);
+		if (err) {
+			netdev_err(dev, "rx buffer allocation failed\n");
+			dev->stats.rx_dropped++;
+			return;
+		}
+
+		dma_unmap_page(&dev->dev, dma, RX_BUF_SIZE, DMA_FROM_DEVICE);
+		memcpy(skb_put(skb, RX_COPYHDR), data, RX_COPYHDR);
+		skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page,
+				offset + RX_COPYHDR, len - RX_COPYHDR,
+				RX_BUF_SIZE);
+	}
+
+	skb->protocol = eth_type_trans(skb, dev);
+	napi_gro_receive(&priv->napi, skb);
+}
+
+static void nb8800_rx_error(struct net_device *dev, u32 report)
+{
+	if (report & RX_LENGTH_ERR)
+		dev->stats.rx_length_errors++;
+
+	if (report & RX_FCS_ERR)
+		dev->stats.rx_crc_errors++;
+
+	if (report & RX_FIFO_OVERRUN)
+		dev->stats.rx_fifo_errors++;
+
+	if (report & RX_ALIGNMENT_ERROR)
+		dev->stats.rx_frame_errors++;
+
+	dev->stats.rx_errors++;
+}
+
+static int nb8800_poll(struct napi_struct *napi, int budget)
+{
+	struct net_device *dev = napi->dev;
+	struct nb8800_priv *priv = netdev_priv(dev);
+	struct nb8800_rx_desc *rxd;
+	int work = 0;
+	int last = priv->rx_eoc;
+	int next;
+
+	nb8800_tx_done(dev);
+
+again:
+	while (work < budget) {
+		struct nb8800_rx_buf *rxb;
+		unsigned int len;
+
+		next = (last + 1) % RX_DESC_COUNT;
+
+		rxb = &priv->rx_bufs[next];
+		rxd = &priv->rx_descs[next];
+
+		if (!rxd->report)
+			break;
+
+		len = RX_BYTES_TRANSFERRED(rxd->report);
+
+		if (IS_RX_ERROR(rxd->report))
+			nb8800_rx_error(dev, rxd->report);
+		else
+			nb8800_receive(dev, next, len);
+
+		dev->stats.rx_packets++;
+		dev->stats.rx_bytes += len;
+
+		if (rxd->report & RX_MULTICAST_PKT)
+			dev->stats.multicast++;
+
+		rxd->report = 0;
+		last = next;
+		work++;
+	}
+
+	if (work) {
+		priv->rx_descs[last].desc.config |= DESC_EOC;
+		wmb();	/* ensure new EOC is written before clearing old */
+		priv->rx_descs[priv->rx_eoc].desc.config &= ~DESC_EOC;
+		priv->rx_eoc = last;
+		nb8800_start_rx(dev);
+	}
+
+	if (work < budget) {
+		nb8800_writel(priv, NB8800_RX_ITR, priv->rx_itr_irq);
+
+		/* If a packet arrived after we last checked but
+		 * before writing RX_ITR, the interrupt will be
+		 * delayed, so we retrieve it now.
+		 */
+		if (priv->rx_descs[next].report)
+			goto again;
+
+		napi_complete_done(napi, work);
+	}
+
+	return work;
+}
+
+static void __nb8800_tx_dma_start(struct net_device *dev)
+{
+	struct nb8800_priv *priv = netdev_priv(dev);
+	struct nb8800_tx_buf *txb;
+	u32 txc_cr;
+
+	txb = &priv->tx_bufs[priv->tx_queue];
+	if (!txb->ready)
+		return;
+
+	txc_cr = nb8800_readl(priv, NB8800_TXC_CR);
+	if (txc_cr & TCR_EN)
+		return;
+
+	nb8800_writel(priv, NB8800_TX_DESC_ADDR, txb->dma_desc);
+	wmb();		/* ensure desc addr is written before starting DMA */
+	nb8800_writel(priv, NB8800_TXC_CR, txc_cr | TCR_EN);
+
+	priv->tx_queue = (priv->tx_queue + txb->chain_len) % TX_DESC_COUNT;
+}
+
+static void nb8800_tx_dma_start(struct net_device *dev)
+{
+	struct nb8800_priv *priv = netdev_priv(dev);
+
+	spin_lock_irq(&priv->tx_lock);
+	__nb8800_tx_dma_start(dev);
+	spin_unlock_irq(&priv->tx_lock);
+}
+
+static void nb8800_tx_dma_start_irq(struct net_device *dev)
+{
+	struct nb8800_priv *priv = netdev_priv(dev);
+
+	spin_lock(&priv->tx_lock);
+	__nb8800_tx_dma_start(dev);
+	spin_unlock(&priv->tx_lock);
+}
+
+static int nb8800_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	struct nb8800_priv *priv = netdev_priv(dev);
+	struct nb8800_tx_desc *txd;
+	struct nb8800_tx_buf *txb;
+	struct nb8800_dma_desc *desc;
+	dma_addr_t dma_addr;
+	unsigned int dma_len;
+	int align;
+	int next;
+
+	if (atomic_read(&priv->tx_free) <= NB8800_DESC_LOW) {
+		netif_stop_queue(dev);
+		return NETDEV_TX_BUSY;
+	}
+
+	align = (8 - (uintptr_t)skb->data) & 7;
+
+	dma_len = skb->len - align;
+	dma_addr = dma_map_single(&dev->dev, skb->data + align,
+				  dma_len, DMA_TO_DEVICE);
+
+	if (dma_mapping_error(&dev->dev, dma_addr)) {
+		netdev_err(dev, "tx dma mapping error\n");
+		kfree_skb(skb);
+		dev->stats.tx_dropped++;
+		return NETDEV_TX_OK;
+	}
+
+	if (atomic_dec_return(&priv->tx_free) <= NB8800_DESC_LOW) {
+		netif_stop_queue(dev);
+		skb->xmit_more = 0;
+	}
+
+	next = priv->tx_next;
+	txb = &priv->tx_bufs[next];
+	txd = &priv->tx_descs[next];
+	desc = &txd->desc[0];
+
+	next = (next + 1) % TX_DESC_COUNT;
+
+	if (align) {
+		memcpy(txd->buf, skb->data, align);
+
+		desc->s_addr =
+			txb->dma_desc + offsetof(struct nb8800_tx_desc, buf);
+		desc->n_addr = txb->dma_desc + sizeof(txd->desc[0]);
+		desc->config = DESC_BTS(2) | DESC_DS | align;
+
+		desc++;
+	}
+
+	desc->s_addr = dma_addr;
+	desc->n_addr = priv->tx_bufs[next].dma_desc;
+	desc->config = DESC_BTS(2) | DESC_DS | DESC_EOF | dma_len;
+
+	if (!skb->xmit_more)
+		desc->config |= DESC_EOC;
+
+	txb->skb = skb;
+	txb->dma_addr = dma_addr;
+	txb->dma_len = dma_len;
+
+	if (!priv->tx_chain) {
+		txb->chain_len = 1;
+		priv->tx_chain = txb;
+	} else {
+		priv->tx_chain->chain_len++;
+	}
+
+	netdev_sent_queue(dev, skb->len);
+
+	priv->tx_next = next;
+
+	if (!skb->xmit_more) {
+		smp_wmb();
+		priv->tx_chain->ready = true;
+		priv->tx_chain = NULL;
+		nb8800_tx_dma_start(dev);
+	}
+
+	return NETDEV_TX_OK;
+}
+
+static void nb8800_tx_error(struct net_device *dev, u32 report)
+{
+	if (report & TX_LATE_COLLISION)
+		dev->stats.collisions++;
+
+	if (report & TX_PACKET_DROPPED)
+		dev->stats.tx_dropped++;
+
+	if (report & TX_FIFO_UNDERRUN)
+		dev->stats.tx_fifo_errors++;
+
+	dev->stats.tx_errors++;
+}
+
+static void nb8800_tx_done(struct net_device *dev)
+{
+	struct nb8800_priv *priv = netdev_priv(dev);
+	int limit = priv->tx_next;
+	int done = priv->tx_done;
+	unsigned int packets = 0;
+	unsigned int len = 0;
+
+	while (done != limit) {
+		struct nb8800_tx_desc *txd = &priv->tx_descs[done];
+		struct nb8800_tx_buf *txb = &priv->tx_bufs[done];
+		struct sk_buff *skb;
+
+		if (!txd->report)
+			break;
+
+		skb = txb->skb;
+		len += skb->len;
+
+		dma_unmap_single(&dev->dev, txb->dma_addr, txb->dma_len,
+				 DMA_TO_DEVICE);
+
+		if (IS_TX_ERROR(txd->report)) {
+			nb8800_tx_error(dev, txd->report);
+			kfree_skb(skb);
+		} else {
+			consume_skb(skb);
+		}
+
+		dev->stats.tx_packets++;
+		dev->stats.tx_bytes += TX_BYTES_TRANSFERRED(txd->report);
+		dev->stats.collisions += TX_EARLY_COLLISIONS(txd->report);
+
+		txb->skb = NULL;
+		txb->ready = false;
+		txd->report = 0;
+
+		done = (done + 1) % TX_DESC_COUNT;
+		packets++;
+	}
+
+	if (packets) {
+		smp_mb__before_atomic();
+		atomic_add(packets, &priv->tx_free);
+		netdev_completed_queue(dev, packets, len);
+		netif_wake_queue(dev);
+		priv->tx_done = done;
+	}
+}
+
+static irqreturn_t nb8800_irq(int irq, void *dev_id)
+{
+	struct net_device *dev = dev_id;
+	struct nb8800_priv *priv = netdev_priv(dev);
+	irqreturn_t ret = IRQ_NONE;
+	u32 val;
+
+	/* tx interrupt */
+	val = nb8800_readl(priv, NB8800_TXC_SR);
+	if (val) {
+		nb8800_writel(priv, NB8800_TXC_SR, val);
+
+		if (val & TSR_DI)
+			nb8800_tx_dma_start_irq(dev);
+
+		if (val & TSR_TI)
+			napi_schedule_irqoff(&priv->napi);
+
+		if (unlikely(val & TSR_DE))
+			netdev_err(dev, "TX DMA error\n");
+
+		/* should never happen with automatic status retrieval */
+		if (unlikely(val & TSR_TO))
+			netdev_err(dev, "TX Status FIFO overflow\n");
+
+		ret = IRQ_HANDLED;
+	}
+
+	/* rx interrupt */
+	val = nb8800_readl(priv, NB8800_RXC_SR);
+	if (val) {
+		nb8800_writel(priv, NB8800_RXC_SR, val);
+
+		if (likely(val & (RSR_RI | RSR_DI))) {
+			nb8800_writel(priv, NB8800_RX_ITR, priv->rx_itr_poll);
+			napi_schedule_irqoff(&priv->napi);
+		}
+
+		if (unlikely(val & RSR_DE))
+			netdev_err(dev, "RX DMA error\n");
+
+		/* should never happen with automatic status retrieval */
+		if (unlikely(val & RSR_RO))
+			netdev_err(dev, "RX Status FIFO overflow\n");
+
+		ret = IRQ_HANDLED;
+	}
+
+	return ret;
+}
+
+static void nb8800_mac_config(struct net_device *dev)
+{
+	struct nb8800_priv *priv = netdev_priv(dev);
+	bool gigabit = priv->speed == SPEED_1000;
+	u32 mac_mode_mask = RGMII_MODE | HALF_DUPLEX | GMAC_MODE;
+	u32 mac_mode = 0;
+	u32 slot_time;
+	u32 phy_clk;
+	u32 ict;
+
+	if (!priv->duplex)
+		mac_mode |= HALF_DUPLEX;
+
+	if (gigabit) {
+		if (priv->phy_mode == PHY_INTERFACE_MODE_RGMII)
+			mac_mode |= RGMII_MODE;
+
+		mac_mode |= GMAC_MODE;
+		phy_clk = 125000000;
+
+		/* Should be 512 but register is only 8 bits */
+		slot_time = 255;
+	} else {
+		phy_clk = 25000000;
+		slot_time = 128;
+	}
+
+	ict = DIV_ROUND_UP(phy_clk, clk_get_rate(priv->clk));
+
+	nb8800_writeb(priv, NB8800_IC_THRESHOLD, ict);
+	nb8800_writeb(priv, NB8800_SLOT_TIME, slot_time);
+	nb8800_maskb(priv, NB8800_MAC_MODE, mac_mode_mask, mac_mode);
+}
+
+static void nb8800_pause_config(struct net_device *dev)
+{
+	struct nb8800_priv *priv = netdev_priv(dev);
+	struct phy_device *phydev = priv->phydev;
+	u32 rxcr;
+
+	if (priv->pause_aneg) {
+		if (!phydev || !phydev->link)
+			return;
+
+		priv->pause_rx = phydev->pause;
+		priv->pause_tx = phydev->pause ^ phydev->asym_pause;
+	}
+
+	nb8800_modb(priv, NB8800_RX_CTL, RX_PAUSE_EN, priv->pause_rx);
+
+	rxcr = nb8800_readl(priv, NB8800_RXC_CR);
+	if (!!(rxcr & RCR_FL) == priv->pause_tx)
+		return;
+
+	if (netif_running(dev)) {
+		napi_disable(&priv->napi);
+		netif_tx_lock_bh(dev);
+		nb8800_dma_stop(dev);
+		nb8800_modl(priv, NB8800_RXC_CR, RCR_FL, priv->pause_tx);
+		nb8800_start_rx(dev);
+		netif_tx_unlock_bh(dev);
+		napi_enable(&priv->napi);
+	} else {
+		nb8800_modl(priv, NB8800_RXC_CR, RCR_FL, priv->pause_tx);
+	}
+}
+
+static void nb8800_link_reconfigure(struct net_device *dev)
+{
+	struct nb8800_priv *priv = netdev_priv(dev);
+	struct phy_device *phydev = priv->phydev;
+	int change = 0;
+
+	if (phydev->link) {
+		if (phydev->speed != priv->speed) {
+			priv->speed = phydev->speed;
+			change = 1;
+		}
+
+		if (phydev->duplex != priv->duplex) {
+			priv->duplex = phydev->duplex;
+			change = 1;
+		}
+
+		if (change)
+			nb8800_mac_config(dev);
+
+		nb8800_pause_config(dev);
+	}
+
+	if (phydev->link != priv->link) {
+		priv->link = phydev->link;
+		change = 1;
+	}
+
+	if (change)
+		phy_print_status(priv->phydev);
+}
+
+static void nb8800_update_mac_addr(struct net_device *dev)
+{
+	struct nb8800_priv *priv = netdev_priv(dev);
+	int i;
+
+	for (i = 0; i < ETH_ALEN; i++)
+		nb8800_writeb(priv, NB8800_SRC_ADDR(i), dev->dev_addr[i]);
+
+	for (i = 0; i < ETH_ALEN; i++)
+		nb8800_writeb(priv, NB8800_UC_ADDR(i), dev->dev_addr[i]);
+}
+
+static int nb8800_set_mac_address(struct net_device *dev, void *addr)
+{
+	struct sockaddr *sock = addr;
+
+	if (netif_running(dev))
+		return -EBUSY;
+
+	ether_addr_copy(dev->dev_addr, sock->sa_data);
+	nb8800_update_mac_addr(dev);
+
+	return 0;
+}
+
+static void nb8800_mc_init(struct net_device *dev, int val)
+{
+	struct nb8800_priv *priv = netdev_priv(dev);
+
+	nb8800_writeb(priv, NB8800_MC_INIT, val);
+	readb_poll_timeout_atomic(priv->base + NB8800_MC_INIT, val, !val,
+				  1, 1000);
+}
+
+static void nb8800_set_rx_mode(struct net_device *dev)
+{
+	struct nb8800_priv *priv = netdev_priv(dev);
+	struct netdev_hw_addr *ha;
+	int i;
+
+	if (dev->flags & (IFF_PROMISC | IFF_ALLMULTI)) {
+		nb8800_mac_af(dev, false);
+		return;
+	}
+
+	nb8800_mac_af(dev, true);
+	nb8800_mc_init(dev, 0);
+
+	netdev_for_each_mc_addr(ha, dev) {
+		for (i = 0; i < ETH_ALEN; i++)
+			nb8800_writeb(priv, NB8800_MC_ADDR(i), ha->addr[i]);
+
+		nb8800_mc_init(dev, 0xff);
+	}
+}
+
+#define RX_DESC_SIZE (RX_DESC_COUNT * sizeof(struct nb8800_rx_desc))
+#define TX_DESC_SIZE (TX_DESC_COUNT * sizeof(struct nb8800_tx_desc))
+
+static void nb8800_dma_free(struct net_device *dev)
+{
+	struct nb8800_priv *priv = netdev_priv(dev);
+	unsigned int i;
+
+	if (priv->rx_bufs) {
+		for (i = 0; i < RX_DESC_COUNT; i++)
+			if (priv->rx_bufs[i].page)
+				put_page(priv->rx_bufs[i].page);
+
+		kfree(priv->rx_bufs);
+		priv->rx_bufs = NULL;
+	}
+
+	if (priv->tx_bufs) {
+		for (i = 0; i < TX_DESC_COUNT; i++)
+			kfree_skb(priv->tx_bufs[i].skb);
+
+		kfree(priv->tx_bufs);
+		priv->tx_bufs = NULL;
+	}
+
+	if (priv->rx_descs) {
+		dma_free_coherent(dev->dev.parent, RX_DESC_SIZE, priv->rx_descs,
+				  priv->rx_desc_dma);
+		priv->rx_descs = NULL;
+	}
+
+	if (priv->tx_descs) {
+		dma_free_coherent(dev->dev.parent, TX_DESC_SIZE, priv->tx_descs,
+				  priv->tx_desc_dma);
+		priv->tx_descs = NULL;
+	}
+}
+
+static void nb8800_dma_reset(struct net_device *dev)
+{
+	struct nb8800_priv *priv = netdev_priv(dev);
+	struct nb8800_rx_desc *rxd;
+	struct nb8800_tx_desc *txd;
+	unsigned int i;
+
+	for (i = 0; i < RX_DESC_COUNT; i++) {
+		dma_addr_t rx_dma = priv->rx_desc_dma + i * sizeof(*rxd);
+
+		rxd = &priv->rx_descs[i];
+		rxd->desc.n_addr = rx_dma + sizeof(*rxd);
+		rxd->desc.r_addr =
+			rx_dma + offsetof(struct nb8800_rx_desc, report);
+		rxd->desc.config = priv->rx_dma_config;
+		rxd->report = 0;
+	}
+
+	rxd->desc.n_addr = priv->rx_desc_dma;
+	rxd->desc.config |= DESC_EOC;
+
+	priv->rx_eoc = RX_DESC_COUNT - 1;
+
+	for (i = 0; i < TX_DESC_COUNT; i++) {
+		struct nb8800_tx_buf *txb = &priv->tx_bufs[i];
+		dma_addr_t r_dma = txb->dma_desc +
+			offsetof(struct nb8800_tx_desc, report);
+
+		txd = &priv->tx_descs[i];
+		txd->desc[0].r_addr = r_dma;
+		txd->desc[1].r_addr = r_dma;
+		txd->report = 0;
+	}
+
+	priv->tx_next = 0;
+	priv->tx_queue = 0;
+	priv->tx_done = 0;
+	atomic_set(&priv->tx_free, TX_DESC_COUNT);
+
+	nb8800_writel(priv, NB8800_RX_DESC_ADDR, priv->rx_desc_dma);
+
+	wmb();		/* ensure all setup is written before starting */
+}
+
+static int nb8800_dma_init(struct net_device *dev)
+{
+	struct nb8800_priv *priv = netdev_priv(dev);
+	unsigned int n_rx = RX_DESC_COUNT;
+	unsigned int n_tx = TX_DESC_COUNT;
+	unsigned int i;
+	int err;
+
+	priv->rx_descs = dma_alloc_coherent(dev->dev.parent, RX_DESC_SIZE,
+					    &priv->rx_desc_dma, GFP_KERNEL);
+	if (!priv->rx_descs)
+		goto err_out;
+
+	priv->rx_bufs = kcalloc(n_rx, sizeof(*priv->rx_bufs), GFP_KERNEL);
+	if (!priv->rx_bufs)
+		goto err_out;
+
+	for (i = 0; i < n_rx; i++) {
+		err = nb8800_alloc_rx(dev, i, false);
+		if (err)
+			goto err_out;
+	}
+
+	priv->tx_descs = dma_alloc_coherent(dev->dev.parent, TX_DESC_SIZE,
+					    &priv->tx_desc_dma, GFP_KERNEL);
+	if (!priv->tx_descs)
+		goto err_out;
+
+	priv->tx_bufs = kcalloc(n_tx, sizeof(*priv->tx_bufs), GFP_KERNEL);
+	if (!priv->tx_bufs)
+		goto err_out;
+
+	for (i = 0; i < n_tx; i++)
+		priv->tx_bufs[i].dma_desc =
+			priv->tx_desc_dma + i * sizeof(struct nb8800_tx_desc);
+
+	nb8800_dma_reset(dev);
+
+	return 0;
+
+err_out:
+	nb8800_dma_free(dev);
+
+	return -ENOMEM;
+}
+
+static int nb8800_dma_stop(struct net_device *dev)
+{
+	struct nb8800_priv *priv = netdev_priv(dev);
+	struct nb8800_tx_buf *txb = &priv->tx_bufs[0];
+	struct nb8800_tx_desc *txd = &priv->tx_descs[0];
+	int retry = 5;
+	u32 txcr;
+	u32 rxcr;
+	int err;
+	unsigned int i;
+
+	/* wait for tx to finish */
+	err = readl_poll_timeout_atomic(priv->base + NB8800_TXC_CR, txcr,
+					!(txcr & TCR_EN) &&
+					priv->tx_done == priv->tx_next,
+					1000, 1000000);
+	if (err)
+		return err;
+
+	/* The rx DMA only stops if it reaches the end of chain.
+	 * To make this happen, we set the EOC flag on all rx
+	 * descriptors, put the device in loopback mode, and send
+	 * a few dummy frames.  The interrupt handler will ignore
+	 * these since NAPI is disabled and no real frames are in
+	 * the tx queue.
+	 */
+
+	for (i = 0; i < RX_DESC_COUNT; i++)
+		priv->rx_descs[i].desc.config |= DESC_EOC;
+
+	txd->desc[0].s_addr =
+		txb->dma_desc + offsetof(struct nb8800_tx_desc, buf);
+	txd->desc[0].config = DESC_BTS(2) | DESC_DS | DESC_EOF | DESC_EOC | 8;
+	memset(txd->buf, 0, sizeof(txd->buf));
+
+	nb8800_mac_af(dev, false);
+	nb8800_setb(priv, NB8800_MAC_MODE, LOOPBACK_EN);
+
+	do {
+		nb8800_writel(priv, NB8800_TX_DESC_ADDR, txb->dma_desc);
+		wmb();
+		nb8800_writel(priv, NB8800_TXC_CR, txcr | TCR_EN);
+
+		err = readl_poll_timeout_atomic(priv->base + NB8800_RXC_CR,
+						rxcr, !(rxcr & RCR_EN),
+						1000, 100000);
+	} while (err && --retry);
+
+	nb8800_mac_af(dev, true);
+	nb8800_clearb(priv, NB8800_MAC_MODE, LOOPBACK_EN);
+	nb8800_dma_reset(dev);
+
+	return retry ? 0 : -ETIMEDOUT;
+}
+
+static void nb8800_pause_adv(struct net_device *dev)
+{
+	struct nb8800_priv *priv = netdev_priv(dev);
+	u32 adv = 0;
+
+	if (!priv->phydev)
+		return;
+
+	if (priv->pause_rx)
+		adv |= ADVERTISED_Pause | ADVERTISED_Asym_Pause;
+	if (priv->pause_tx)
+		adv ^= ADVERTISED_Asym_Pause;
+
+	priv->phydev->supported |= adv;
+	priv->phydev->advertising |= adv;
+}
+
+static int nb8800_open(struct net_device *dev)
+{
+	struct nb8800_priv *priv = netdev_priv(dev);
+	int err;
+
+	/* clear any pending interrupts */
+	nb8800_writel(priv, NB8800_RXC_SR, 0xf);
+	nb8800_writel(priv, NB8800_TXC_SR, 0xf);
+
+	err = nb8800_dma_init(dev);
+	if (err)
+		return err;
+
+	err = request_irq(dev->irq, nb8800_irq, 0, dev_name(&dev->dev), dev);
+	if (err)
+		goto err_free_dma;
+
+	nb8800_mac_rx(dev, true);
+	nb8800_mac_tx(dev, true);
+
+	priv->phydev = of_phy_connect(dev, priv->phy_node,
+				      nb8800_link_reconfigure, 0,
+				      priv->phy_mode);
+	if (!priv->phydev)
+		goto err_free_irq;
+
+	nb8800_pause_adv(dev);
+
+	netdev_reset_queue(dev);
+	napi_enable(&priv->napi);
+	netif_start_queue(dev);
+
+	nb8800_start_rx(dev);
+	phy_start(priv->phydev);
+
+	return 0;
+
+err_free_irq:
+	free_irq(dev->irq, dev);
+err_free_dma:
+	nb8800_dma_free(dev);
+
+	return err;
+}
+
+static int nb8800_stop(struct net_device *dev)
+{
+	struct nb8800_priv *priv = netdev_priv(dev);
+
+	phy_stop(priv->phydev);
+
+	netif_stop_queue(dev);
+	napi_disable(&priv->napi);
+
+	nb8800_dma_stop(dev);
+	nb8800_mac_rx(dev, false);
+	nb8800_mac_tx(dev, false);
+
+	phy_disconnect(priv->phydev);
+	priv->phydev = NULL;
+
+	free_irq(dev->irq, dev);
+
+	nb8800_dma_free(dev);
+
+	return 0;
+}
+
+static int nb8800_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
+{
+	struct nb8800_priv *priv = netdev_priv(dev);
+
+	return phy_mii_ioctl(priv->phydev, rq, cmd);
+}
+
+static const struct net_device_ops nb8800_netdev_ops = {
+	.ndo_open		= nb8800_open,
+	.ndo_stop		= nb8800_stop,
+	.ndo_start_xmit		= nb8800_xmit,
+	.ndo_set_mac_address	= nb8800_set_mac_address,
+	.ndo_set_rx_mode	= nb8800_set_rx_mode,
+	.ndo_do_ioctl		= nb8800_ioctl,
+	.ndo_change_mtu		= eth_change_mtu,
+	.ndo_validate_addr	= eth_validate_addr,
+};
+
+static int nb8800_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
+{
+	struct nb8800_priv *priv = netdev_priv(dev);
+
+	if (!priv->phydev)
+		return -ENODEV;
+
+	return phy_ethtool_gset(priv->phydev, cmd);
+}
+
+static int nb8800_set_settings(struct net_device *dev, struct ethtool_cmd *cmd)
+{
+	struct nb8800_priv *priv = netdev_priv(dev);
+
+	if (!priv->phydev)
+		return -ENODEV;
+
+	return phy_ethtool_sset(priv->phydev, cmd);
+}
+
+static int nb8800_nway_reset(struct net_device *dev)
+{
+	struct nb8800_priv *priv = netdev_priv(dev);
+
+	if (!priv->phydev)
+		return -ENODEV;
+
+	return genphy_restart_aneg(priv->phydev);
+}
+
+static void nb8800_get_pauseparam(struct net_device *dev,
+				  struct ethtool_pauseparam *pp)
+{
+	struct nb8800_priv *priv = netdev_priv(dev);
+
+	pp->autoneg = priv->pause_aneg;
+	pp->rx_pause = priv->pause_rx;
+	pp->tx_pause = priv->pause_tx;
+}
+
+static int nb8800_set_pauseparam(struct net_device *dev,
+				 struct ethtool_pauseparam *pp)
+{
+	struct nb8800_priv *priv = netdev_priv(dev);
+
+	priv->pause_aneg = pp->autoneg;
+	priv->pause_rx = pp->rx_pause;
+	priv->pause_tx = pp->tx_pause;
+
+	nb8800_pause_adv(dev);
+
+	if (!priv->pause_aneg)
+		nb8800_pause_config(dev);
+	else if (priv->phydev)
+		phy_start_aneg(priv->phydev);
+
+	return 0;
+}
+
+static const char nb8800_stats_names[][ETH_GSTRING_LEN] = {
+	"rx_bytes_ok",
+	"rx_frames_ok",
+	"rx_undersize_frames",
+	"rx_fragment_frames",
+	"rx_64_byte_frames",
+	"rx_127_byte_frames",
+	"rx_255_byte_frames",
+	"rx_511_byte_frames",
+	"rx_1023_byte_frames",
+	"rx_max_size_frames",
+	"rx_oversize_frames",
+	"rx_bad_fcs_frames",
+	"rx_broadcast_frames",
+	"rx_multicast_frames",
+	"rx_control_frames",
+	"rx_pause_frames",
+	"rx_unsup_control_frames",
+	"rx_align_error_frames",
+	"rx_overrun_frames",
+	"rx_jabber_frames",
+	"rx_bytes",
+	"rx_frames",
+
+	"tx_bytes_ok",
+	"tx_frames_ok",
+	"tx_64_byte_frames",
+	"tx_127_byte_frames",
+	"tx_255_byte_frames",
+	"tx_511_byte_frames",
+	"tx_1023_byte_frames",
+	"tx_max_size_frames",
+	"tx_oversize_frames",
+	"tx_broadcast_frames",
+	"tx_multicast_frames",
+	"tx_control_frames",
+	"tx_pause_frames",
+	"tx_underrun_frames",
+	"tx_single_collision_frames",
+	"tx_multi_collision_frames",
+	"tx_deferred_collision_frames",
+	"tx_late_collision_frames",
+	"tx_excessive_collision_frames",
+	"tx_bytes",
+	"tx_frames",
+	"tx_collisions",
+};
+
+#define NB8800_NUM_STATS ARRAY_SIZE(nb8800_stats_names)
+
+static int nb8800_get_sset_count(struct net_device *dev, int sset)
+{
+	if (sset == ETH_SS_STATS)
+		return NB8800_NUM_STATS;
+
+	return -EOPNOTSUPP;
+}
+
+static void nb8800_get_strings(struct net_device *dev, u32 sset, u8 *buf)
+{
+	if (sset == ETH_SS_STATS)
+		memcpy(buf, &nb8800_stats_names, sizeof(nb8800_stats_names));
+}
+
+static u32 nb8800_read_stat(struct net_device *dev, int index)
+{
+	struct nb8800_priv *priv = netdev_priv(dev);
+
+	nb8800_writeb(priv, NB8800_STAT_INDEX, index);
+
+	return nb8800_readl(priv, NB8800_STAT_DATA);
+}
+
+static void nb8800_get_ethtool_stats(struct net_device *dev,
+				     struct ethtool_stats *estats, u64 *st)
+{
+	unsigned int i;
+	u32 rx, tx;
+
+	for (i = 0; i < NB8800_NUM_STATS / 2; i++) {
+		rx = nb8800_read_stat(dev, i);
+		tx = nb8800_read_stat(dev, i | 0x80);
+		st[i] = rx;
+		st[i + NB8800_NUM_STATS / 2] = tx;
+	}
+}
+
+static const struct ethtool_ops nb8800_ethtool_ops = {
+	.get_settings		= nb8800_get_settings,
+	.set_settings		= nb8800_set_settings,
+	.nway_reset		= nb8800_nway_reset,
+	.get_link		= ethtool_op_get_link,
+	.get_pauseparam		= nb8800_get_pauseparam,
+	.set_pauseparam		= nb8800_set_pauseparam,
+	.get_sset_count		= nb8800_get_sset_count,
+	.get_strings		= nb8800_get_strings,
+	.get_ethtool_stats	= nb8800_get_ethtool_stats,
+};
+
+static int nb8800_hw_init(struct net_device *dev)
+{
+	struct nb8800_priv *priv = netdev_priv(dev);
+	u32 val;
+
+	val = TX_RETRY_EN | TX_PAD_EN | TX_APPEND_FCS;
+	nb8800_writeb(priv, NB8800_TX_CTL1, val);
+
+	/* Collision retry count */
+	nb8800_writeb(priv, NB8800_TX_CTL2, 5);
+
+	val = RX_PAD_STRIP | RX_AF_EN;
+	nb8800_writeb(priv, NB8800_RX_CTL, val);
+
+	/* Chosen by fair dice roll */
+	nb8800_writeb(priv, NB8800_RANDOM_SEED, 4);
+
+	/* TX cycles per deferral period */
+	nb8800_writeb(priv, NB8800_TX_SDP, 12);
+
+	/* The following three threshold values have been
+	 * experimentally determined for good results.
+	 */
+
+	/* RX/TX FIFO threshold for partial empty (64-bit entries) */
+	nb8800_writeb(priv, NB8800_PE_THRESHOLD, 0);
+
+	/* RX/TX FIFO threshold for partial full (64-bit entries) */
+	nb8800_writeb(priv, NB8800_PF_THRESHOLD, 255);
+
+	/* Buffer size for transmit (64-bit entries) */
+	nb8800_writeb(priv, NB8800_TX_BUFSIZE, 64);
+
+	/* Configure tx DMA */
+
+	val = nb8800_readl(priv, NB8800_TXC_CR);
+	val &= TCR_LE;		/* keep endian setting */
+	val |= TCR_DM;		/* DMA descriptor mode */
+	val |= TCR_RS;		/* automatically store tx status  */
+	val |= TCR_DIE;		/* interrupt on DMA chain completion */
+	val |= TCR_TFI(7);	/* interrupt after 7 frames transmitted */
+	val |= TCR_BTS(2);	/* 32-byte bus transaction size */
+	nb8800_writel(priv, NB8800_TXC_CR, val);
+
+	/* TX complete interrupt after 10 ms or 7 frames (see above) */
+	val = clk_get_rate(priv->clk) / 100;
+	nb8800_writel(priv, NB8800_TX_ITR, val);
+
+	/* Configure rx DMA */
+
+	val = nb8800_readl(priv, NB8800_RXC_CR);
+	val &= RCR_LE;		/* keep endian setting */
+	val |= RCR_DM;		/* DMA descriptor mode */
+	val |= RCR_RS;		/* automatically store rx status */
+	val |= RCR_DIE;		/* interrupt at end of DMA chain */
+	val |= RCR_RFI(7);	/* interrupt after 7 frames received */
+	val |= RCR_BTS(2);	/* 32-byte bus transaction size */
+	nb8800_writel(priv, NB8800_RXC_CR, val);
+
+	/* The rx interrupt can fire before the DMA has completed
+	 * unless a small delay is added.  50 us is hopefully enough.
+	 */
+	priv->rx_itr_irq = clk_get_rate(priv->clk) / 20000;
+
+	/* In NAPI poll mode we want to disable interrupts, but the
+	 * hardware does not permit this.  Delay 10 ms instead.
+	 */
+	priv->rx_itr_poll = clk_get_rate(priv->clk) / 100;
+
+	nb8800_writel(priv, NB8800_RX_ITR, priv->rx_itr_irq);
+
+	priv->rx_dma_config = RX_BUF_SIZE | DESC_BTS(2) | DESC_DS | DESC_EOF;
+
+	/* Flow control settings */
+
+	/* Pause time of 0.1 ms */
+	val = 100000 / 512;
+	nb8800_writeb(priv, NB8800_PQ1, val >> 8);
+	nb8800_writeb(priv, NB8800_PQ2, val & 0xff);
+
+	/* Auto-negotiate by default */
+	priv->pause_aneg = true;
+	priv->pause_rx = true;
+	priv->pause_tx = true;
+
+	nb8800_mc_init(dev, 0);
+
+	return 0;
+}
+
+static int nb8800_tangox_init(struct net_device *dev)
+{
+	struct nb8800_priv *priv = netdev_priv(dev);
+	u32 pad_mode = PAD_MODE_MII;
+
+	switch (priv->phy_mode) {
+	case PHY_INTERFACE_MODE_MII:
+	case PHY_INTERFACE_MODE_GMII:
+		pad_mode = PAD_MODE_MII;
+		break;
+
+	case PHY_INTERFACE_MODE_RGMII:
+		pad_mode = PAD_MODE_RGMII;
+		break;
+
+	case PHY_INTERFACE_MODE_RGMII_TXID:
+		pad_mode = PAD_MODE_RGMII | PAD_MODE_GTX_CLK_DELAY;
+		break;
+
+	default:
+		dev_err(dev->dev.parent, "unsupported phy mode %s\n",
+			phy_modes(priv->phy_mode));
+		return -EINVAL;
+	}
+
+	nb8800_writeb(priv, NB8800_TANGOX_PAD_MODE, pad_mode);
+
+	return 0;
+}
+
+static int nb8800_tangox_reset(struct net_device *dev)
+{
+	struct nb8800_priv *priv = netdev_priv(dev);
+	int clk_div;
+
+	nb8800_writeb(priv, NB8800_TANGOX_RESET, 0);
+	usleep_range(1000, 10000);
+	nb8800_writeb(priv, NB8800_TANGOX_RESET, 1);
+
+	wmb();		/* ensure reset is cleared before proceeding */
+
+	clk_div = DIV_ROUND_UP(clk_get_rate(priv->clk), 2 * MAX_MDC_CLOCK);
+	nb8800_writew(priv, NB8800_TANGOX_MDIO_CLKDIV, clk_div);
+
+	return 0;
+}
+
+static const struct nb8800_ops nb8800_tangox_ops = {
+	.init	= nb8800_tangox_init,
+	.reset	= nb8800_tangox_reset,
+};
+
+static int nb8800_tango4_init(struct net_device *dev)
+{
+	struct nb8800_priv *priv = netdev_priv(dev);
+	int err;
+
+	err = nb8800_tangox_init(dev);
+	if (err)
+		return err;
+
+	/* On tango4 interrupt on DMA completion per frame works and gives
+	 * better performance despite generating more rx interrupts.
+	 */
+
+	/* Disable unnecessary interrupt on rx completion */
+	nb8800_clearl(priv, NB8800_RXC_CR, RCR_RFI(7));
+
+	/* Request interrupt on descriptor DMA completion */
+	priv->rx_dma_config |= DESC_ID;
+
+	return 0;
+}
+
+static const struct nb8800_ops nb8800_tango4_ops = {
+	.init	= nb8800_tango4_init,
+	.reset	= nb8800_tangox_reset,
+};
+
+static const struct of_device_id nb8800_dt_ids[] = {
+	{
+		.compatible = "aurora,nb8800",
+	},
+	{
+		.compatible = "sigma,smp8642-ethernet",
+		.data = &nb8800_tangox_ops,
+	},
+	{
+		.compatible = "sigma,smp8734-ethernet",
+		.data = &nb8800_tango4_ops,
+	},
+	{ }
+};
+
+static int nb8800_probe(struct platform_device *pdev)
+{
+	const struct of_device_id *match;
+	const struct nb8800_ops *ops = NULL;
+	struct nb8800_priv *priv;
+	struct resource *res;
+	struct net_device *dev;
+	struct mii_bus *bus;
+	const unsigned char *mac;
+	void __iomem *base;
+	int irq;
+	int ret;
+
+	match = of_match_device(nb8800_dt_ids, &pdev->dev);
+	if (match)
+		ops = match->data;
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq <= 0) {
+		dev_err(&pdev->dev, "No IRQ\n");
+		return -EINVAL;
+	}
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(base))
+		return PTR_ERR(base);
+
+	dev_dbg(&pdev->dev, "AU-NB8800 Ethernet at %pa\n", &res->start);
+
+	dev = alloc_etherdev(sizeof(*priv));
+	if (!dev)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, dev);
+	SET_NETDEV_DEV(dev, &pdev->dev);
+
+	priv = netdev_priv(dev);
+	priv->base = base;
+
+	priv->phy_mode = of_get_phy_mode(pdev->dev.of_node);
+	if (priv->phy_mode < 0)
+		priv->phy_mode = PHY_INTERFACE_MODE_RGMII;
+
+	priv->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(priv->clk)) {
+		dev_err(&pdev->dev, "failed to get clock\n");
+		ret = PTR_ERR(priv->clk);
+		goto err_free_dev;
+	}
+
+	ret = clk_prepare_enable(priv->clk);
+	if (ret)
+		goto err_free_dev;
+
+	spin_lock_init(&priv->tx_lock);
+
+	if (ops && ops->reset) {
+		ret = ops->reset(dev);
+		if (ret)
+			goto err_free_dev;
+	}
+
+	bus = devm_mdiobus_alloc(&pdev->dev);
+	if (!bus) {
+		ret = -ENOMEM;
+		goto err_disable_clk;
+	}
+
+	bus->name = "nb8800-mii";
+	bus->read = nb8800_mdio_read;
+	bus->write = nb8800_mdio_write;
+	bus->parent = &pdev->dev;
+	snprintf(bus->id, MII_BUS_ID_SIZE, "%lx.nb8800-mii",
+		 (unsigned long)res->start);
+	bus->priv = priv;
+
+	ret = of_mdiobus_register(bus, pdev->dev.of_node);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to register MII bus\n");
+		goto err_disable_clk;
+	}
+
+	priv->phy_node = of_parse_phandle(pdev->dev.of_node, "phy-handle", 0);
+	if (!priv->phy_node) {
+		dev_err(&pdev->dev, "no PHY specified\n");
+		ret = -ENODEV;
+		goto err_free_bus;
+	}
+
+	priv->mii_bus = bus;
+
+	ret = nb8800_hw_init(dev);
+	if (ret)
+		goto err_free_bus;
+
+	if (ops && ops->init) {
+		ret = ops->init(dev);
+		if (ret)
+			goto err_free_bus;
+	}
+
+	dev->netdev_ops = &nb8800_netdev_ops;
+	dev->ethtool_ops = &nb8800_ethtool_ops;
+	dev->flags |= IFF_MULTICAST;
+	dev->irq = irq;
+
+	mac = of_get_mac_address(pdev->dev.of_node);
+	if (mac)
+		ether_addr_copy(dev->dev_addr, mac);
+
+	if (!is_valid_ether_addr(dev->dev_addr))
+		eth_hw_addr_random(dev);
+
+	nb8800_update_mac_addr(dev);
+
+	netif_carrier_off(dev);
+
+	ret = register_netdev(dev);
+	if (ret) {
+		netdev_err(dev, "failed to register netdev\n");
+		goto err_free_dma;
+	}
+
+	netif_napi_add(dev, &priv->napi, nb8800_poll, NAPI_POLL_WEIGHT);
+
+	netdev_info(dev, "MAC address %pM\n", dev->dev_addr);
+
+	return 0;
+
+err_free_dma:
+	nb8800_dma_free(dev);
+err_free_bus:
+	mdiobus_unregister(bus);
+err_disable_clk:
+	clk_disable_unprepare(priv->clk);
+err_free_dev:
+	free_netdev(dev);
+
+	return ret;
+}
+
+static int nb8800_remove(struct platform_device *pdev)
+{
+	struct net_device *ndev = platform_get_drvdata(pdev);
+	struct nb8800_priv *priv = netdev_priv(ndev);
+
+	unregister_netdev(ndev);
+
+	mdiobus_unregister(priv->mii_bus);
+
+	clk_disable_unprepare(priv->clk);
+
+	nb8800_dma_free(ndev);
+	free_netdev(ndev);
+
+	return 0;
+}
+
+static struct platform_driver nb8800_driver = {
+	.driver = {
+		.name		= "nb8800",
+		.of_match_table	= nb8800_dt_ids,
+	},
+	.probe	= nb8800_probe,
+	.remove	= nb8800_remove,
+};
+
+module_platform_driver(nb8800_driver);
+
+MODULE_DESCRIPTION("Aurora AU-NB8800 Ethernet driver");
+MODULE_AUTHOR("Mans Rullgard <mans@mansr.com>");
+MODULE_LICENSE("GPL");
diff --git a/drivers/net/ethernet/aurora/nb8800.h b/drivers/net/ethernet/aurora/nb8800.h
new file mode 100644
index 0000000..e5adbc2
--- /dev/null
+++ b/drivers/net/ethernet/aurora/nb8800.h
@@ -0,0 +1,316 @@ 
+#ifndef _NB8800_H_
+#define _NB8800_H_
+
+#include <linux/types.h>
+#include <linux/skbuff.h>
+#include <linux/phy.h>
+#include <linux/clk.h>
+#include <linux/bitops.h>
+
+#define RX_DESC_COUNT			256
+#define TX_DESC_COUNT			256
+
+#define NB8800_DESC_LOW			4
+
+#define RX_BUF_SIZE			1552
+
+#define RX_COPYBREAK			256
+#define RX_COPYHDR			128
+
+#define MAX_MDC_CLOCK			2500000
+
+/* Stargate Solutions SSN8800 core registers */
+#define NB8800_TX_CTL1			0x000
+#define TX_TPD				BIT(5)
+#define TX_APPEND_FCS			BIT(4)
+#define TX_PAD_EN			BIT(3)
+#define TX_RETRY_EN			BIT(2)
+#define TX_EN				BIT(0)
+
+#define NB8800_TX_CTL2			0x001
+
+#define NB8800_RX_CTL			0x004
+#define RX_BC_DISABLE			BIT(7)
+#define RX_RUNT				BIT(6)
+#define RX_AF_EN			BIT(5)
+#define RX_PAUSE_EN			BIT(3)
+#define RX_SEND_CRC			BIT(2)
+#define RX_PAD_STRIP			BIT(1)
+#define RX_EN				BIT(0)
+
+#define NB8800_RANDOM_SEED		0x008
+#define NB8800_TX_SDP			0x14
+#define NB8800_TX_TPDP1			0x18
+#define NB8800_TX_TPDP2			0x19
+#define NB8800_SLOT_TIME		0x1c
+
+#define NB8800_MDIO_CMD			0x020
+#define MDIO_CMD_GO			BIT(31)
+#define MDIO_CMD_WR			BIT(26)
+#define MDIO_CMD_ADDR(x)		((x) << 21)
+#define MDIO_CMD_REG(x)			((x) << 16)
+#define MDIO_CMD_DATA(x)		((x) <<	 0)
+
+#define NB8800_MDIO_STS			0x024
+#define MDIO_STS_ERR			BIT(31)
+
+#define NB8800_MC_ADDR(i)		(0x028 + (i))
+#define NB8800_MC_INIT			0x02e
+#define NB8800_UC_ADDR(i)		(0x03c + (i))
+
+#define NB8800_MAC_MODE			0x044
+#define RGMII_MODE			BIT(7)
+#define HALF_DUPLEX			BIT(4)
+#define BURST_EN			BIT(3)
+#define LOOPBACK_EN			BIT(2)
+#define GMAC_MODE			BIT(0)
+
+#define NB8800_IC_THRESHOLD		0x050
+#define NB8800_PE_THRESHOLD		0x051
+#define NB8800_PF_THRESHOLD		0x052
+#define NB8800_TX_BUFSIZE		0x054
+#define NB8800_FIFO_CTL			0x056
+#define NB8800_PQ1			0x060
+#define NB8800_PQ2			0x061
+#define NB8800_SRC_ADDR(i)		(0x06a + (i))
+#define NB8800_STAT_DATA		0x078
+#define NB8800_STAT_INDEX		0x07c
+#define NB8800_STAT_CLEAR		0x07d
+
+#define NB8800_SLEEP_MODE		0x07e
+#define SLEEP_MODE			BIT(0)
+
+#define NB8800_WAKEUP			0x07f
+#define WAKEUP				BIT(0)
+
+/* Aurora NB8800 host interface registers */
+#define NB8800_TXC_CR			0x100
+#define TCR_LK				BIT(12)
+#define TCR_DS				BIT(11)
+#define TCR_BTS(x)			(((x) & 0x7) << 8)
+#define TCR_DIE				BIT(7)
+#define TCR_TFI(x)			(((x) & 0x7) << 4)
+#define TCR_LE				BIT(3)
+#define TCR_RS				BIT(2)
+#define TCR_DM				BIT(1)
+#define TCR_EN				BIT(0)
+
+#define NB8800_TXC_SR			0x104
+#define TSR_DE				BIT(3)
+#define TSR_DI				BIT(2)
+#define TSR_TO				BIT(1)
+#define TSR_TI				BIT(0)
+
+#define NB8800_TX_SAR			0x108
+#define NB8800_TX_DESC_ADDR		0x10c
+
+#define NB8800_TX_REPORT_ADDR		0x110
+#define TX_BYTES_TRANSFERRED(x)		(((x) >> 16) & 0xffff)
+#define TX_FIRST_DEFERRAL		BIT(7)
+#define TX_EARLY_COLLISIONS(x)		(((x) >> 3) & 0xf)
+#define TX_LATE_COLLISION		BIT(2)
+#define TX_PACKET_DROPPED		BIT(1)
+#define TX_FIFO_UNDERRUN		BIT(0)
+#define IS_TX_ERROR(r)			((r) & 0x07)
+
+#define NB8800_TX_FIFO_SR		0x114
+#define NB8800_TX_ITR			0x118
+
+#define NB8800_RXC_CR			0x200
+#define RCR_FL				BIT(13)
+#define RCR_LK				BIT(12)
+#define RCR_DS				BIT(11)
+#define RCR_BTS(x)			(((x) & 7) << 8)
+#define RCR_DIE				BIT(7)
+#define RCR_RFI(x)			(((x) & 7) << 4)
+#define RCR_LE				BIT(3)
+#define RCR_RS				BIT(2)
+#define RCR_DM				BIT(1)
+#define RCR_EN				BIT(0)
+
+#define NB8800_RXC_SR			0x204
+#define RSR_DE				BIT(3)
+#define RSR_DI				BIT(2)
+#define RSR_RO				BIT(1)
+#define RSR_RI				BIT(0)
+
+#define NB8800_RX_SAR			0x208
+#define NB8800_RX_DESC_ADDR		0x20c
+
+#define NB8800_RX_REPORT_ADDR		0x210
+#define RX_BYTES_TRANSFERRED(x)		(((x) >> 16) & 0xFFFF)
+#define RX_MULTICAST_PKT		BIT(9)
+#define RX_BROADCAST_PKT		BIT(8)
+#define RX_LENGTH_ERR			BIT(7)
+#define RX_FCS_ERR			BIT(6)
+#define RX_RUNT_PKT			BIT(5)
+#define RX_FIFO_OVERRUN			BIT(4)
+#define RX_LATE_COLLISION		BIT(3)
+#define RX_ALIGNMENT_ERROR		BIT(2)
+#define RX_ERROR_MASK			0xfc
+#define IS_RX_ERROR(r)			((r) & RX_ERROR_MASK)
+
+#define NB8800_RX_FIFO_SR		0x214
+#define NB8800_RX_ITR			0x218
+
+/* Sigma Designs SMP86xx additional registers */
+#define NB8800_TANGOX_PAD_MODE		0x400
+#define PAD_MODE_MASK			0x7
+#define PAD_MODE_MII			0x0
+#define PAD_MODE_RGMII			0x1
+#define PAD_MODE_GTX_CLK_INV		BIT(3)
+#define PAD_MODE_GTX_CLK_DELAY		BIT(4)
+
+#define NB8800_TANGOX_MDIO_CLKDIV	0x420
+#define NB8800_TANGOX_RESET		0x424
+
+/* Hardware DMA descriptor */
+struct nb8800_dma_desc {
+	u32				s_addr;	/* start address */
+	u32				n_addr;	/* next descriptor address */
+	u32				r_addr;	/* report address */
+	u32				config;
+} __aligned(8);
+
+#define DESC_ID				BIT(23)
+#define DESC_EOC			BIT(22)
+#define DESC_EOF			BIT(21)
+#define DESC_LK				BIT(20)
+#define DESC_DS				BIT(19)
+#define DESC_BTS(x)			(((x) & 0x7) << 16)
+
+/* DMA descriptor and associated data for rx.
+ * Allocated from coherent memory.
+ */
+struct nb8800_rx_desc {
+	/* DMA descriptor */
+	struct nb8800_dma_desc		desc;
+
+	/* Status report filled in by hardware */
+	u32				report;
+};
+
+/* Address of buffer on rx ring */
+struct nb8800_rx_buf {
+	struct page			*page;
+	unsigned long			offset;
+};
+
+/* DMA descriptors and associated data for tx.
+ * Allocated from coherent memory.
+ */
+struct nb8800_tx_desc {
+	/* DMA descriptor.  The second descriptor is used if packet
+	 * data is unaligned.
+	 */
+	struct nb8800_dma_desc		desc[2];
+
+	/* Status report filled in by hardware */
+	u32				report;
+
+	/* Bounce buffer for initial unaligned part of packet */
+	u8				buf[8] __aligned(8);
+};
+
+/* Packet in tx queue */
+struct nb8800_tx_buf {
+	/* Currently queued skb */
+	struct sk_buff			*skb;
+
+	/* DMA address of the first descriptor */
+	dma_addr_t			dma_desc;
+
+	/* DMA address of packet data */
+	dma_addr_t			dma_addr;
+
+	/* Length of DMA mapping, less than skb->len if alignment
+	 * buffer is used.
+	 */
+	unsigned int			dma_len;
+
+	/* Number of packets in chain starting here */
+	unsigned int			chain_len;
+
+	/* Packet chain ready to be submitted to hardware */
+	bool				ready;
+};
+
+struct nb8800_priv {
+	struct napi_struct		napi;
+
+	void __iomem			*base;
+
+	/* RX DMA descriptors */
+	struct nb8800_rx_desc		*rx_descs;
+
+	/* RX buffers referenced by DMA descriptors */
+	struct nb8800_rx_buf		*rx_bufs;
+
+	/* Current end of chain */
+	u32				rx_eoc;
+
+	/* Value for rx interrupt time register in NAPI interrupt mode */
+	u32				rx_itr_irq;
+
+	/* Value for rx interrupt time register in NAPI poll mode */
+	u32				rx_itr_poll;
+
+	/* Value for config field of rx DMA descriptors */
+	u32				rx_dma_config;
+
+	/* TX DMA descriptors */
+	struct nb8800_tx_desc		*tx_descs;
+
+	/* TX packet queue */
+	struct nb8800_tx_buf		*tx_bufs;
+
+	/* Number of free tx queue entries */
+	atomic_t			tx_free;
+
+	/* First free tx queue entry */
+	u32				tx_next;
+
+	/* Next buffer to transmit */
+	u32				tx_queue;
+
+	/* Start of current packet chain */
+	struct nb8800_tx_buf		*tx_chain;
+
+	/* Next buffer to reclaim */
+	u32				tx_done;
+
+	/* Lock for DMA activation */
+	spinlock_t			tx_lock;
+
+	struct mii_bus			*mii_bus;
+	struct device_node		*phy_node;
+	struct phy_device		*phydev;
+
+	/* PHY connection type from DT */
+	int				phy_mode;
+
+	/* Current link status */
+	int				speed;
+	int				duplex;
+	int				link;
+
+	/* Pause settings */
+	bool				pause_aneg;
+	bool				pause_rx;
+	bool				pause_tx;
+
+	/* DMA base address of rx descriptors, see rx_descs above */
+	dma_addr_t			rx_desc_dma;
+
+	/* DMA base address of tx descriptors, see tx_descs above */
+	dma_addr_t			tx_desc_dma;
+
+	struct clk			*clk;
+};
+
+struct nb8800_ops {
+	int				(*init)(struct net_device *dev);
+	int				(*reset)(struct net_device *dev);
+};
+
+#endif /* _NB8800_H_ */