Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1156 insertions, 0 deletions

diff --git a/drivers/net/ethernet/allwinner/sun4i-emac.c b/drivers/net/ethernet/allwinner/sun4i-emac.c
new file mode 100644
index 0000000000..a94c62956e
--- /dev/null
+++ b/drivers/net/ethernet/allwinner/sun4i-emac.c
@@ -0,0 +1,1156 @@
+/*
+ * Allwinner EMAC Fast Ethernet driver for Linux.
+ *
+ * Copyright 2012-2013 Stefan Roese <sr@denx.de>
+ * Copyright 2013 Maxime Ripard <maxime.ripard@free-electrons.com>
+ *
+ * Based on the Linux driver provided by Allwinner:
+ * Copyright (C) 1997  Sten Wang
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/clk.h>
+#include <linux/etherdevice.h>
+#include <linux/ethtool.h>
+#include <linux/gpio.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/mii.h>
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of_mdio.h>
+#include <linux/of_net.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/phy.h>
+#include <linux/soc/sunxi/sunxi_sram.h>
+#include <linux/dmaengine.h>
+
+#include "sun4i-emac.h"
+
+#define DRV_NAME		"sun4i-emac"
+
+#define EMAC_MAX_FRAME_LEN	0x0600
+
+#define EMAC_DEFAULT_MSG_ENABLE 0x0000
+static int debug = -1;     /* defaults above */;
+module_param(debug, int, 0);
+MODULE_PARM_DESC(debug, "debug message flags");
+
+/* Transmit timeout, default 5 seconds. */
+static int watchdog = 5000;
+module_param(watchdog, int, 0400);
+MODULE_PARM_DESC(watchdog, "transmit timeout in milliseconds");
+
+/* EMAC register address locking.
+ *
+ * The EMAC uses an address register to control where data written
+ * to the data register goes. This means that the address register
+ * must be preserved over interrupts or similar calls.
+ *
+ * During interrupt and other critical calls, a spinlock is used to
+ * protect the system, but the calls themselves save the address
+ * in the address register in case they are interrupting another
+ * access to the device.
+ *
+ * For general accesses a lock is provided so that calls which are
+ * allowed to sleep are serialised so that the address register does
+ * not need to be saved. This lock also serves to serialise access
+ * to the EEPROM and PHY access registers which are shared between
+ * these two devices.
+ */
+
+/* The driver supports the original EMACE, and now the two newer
+ * devices, EMACA and EMACB.
+ */
+
+struct emac_board_info {
+	struct clk		*clk;
+	struct device		*dev;
+	struct platform_device	*pdev;
+	spinlock_t		lock;
+	void __iomem		*membase;
+	u32			msg_enable;
+	struct net_device	*ndev;
+	u16			tx_fifo_stat;
+
+	int			emacrx_completed_flag;
+
+	struct device_node	*phy_node;
+	unsigned int		link;
+	unsigned int		speed;
+	unsigned int		duplex;
+
+	phy_interface_t		phy_interface;
+	struct dma_chan	*rx_chan;
+	phys_addr_t emac_rx_fifo;
+};
+
+struct emac_dma_req {
+	struct emac_board_info *db;
+	struct dma_async_tx_descriptor *desc;
+	struct sk_buff *skb;
+	dma_addr_t rxbuf;
+	int count;
+};
+
+static void emac_update_speed(struct net_device *dev)
+{
+	struct emac_board_info *db = netdev_priv(dev);
+	unsigned int reg_val;
+
+	/* set EMAC SPEED, depend on PHY  */
+	reg_val = readl(db->membase + EMAC_MAC_SUPP_REG);
+	reg_val &= ~EMAC_MAC_SUPP_100M;
+	if (db->speed == SPEED_100)
+		reg_val |= EMAC_MAC_SUPP_100M;
+	writel(reg_val, db->membase + EMAC_MAC_SUPP_REG);
+}
+
+static void emac_update_duplex(struct net_device *dev)
+{
+	struct emac_board_info *db = netdev_priv(dev);
+	unsigned int reg_val;
+
+	/* set duplex depend on phy */
+	reg_val = readl(db->membase + EMAC_MAC_CTL1_REG);
+	reg_val &= ~EMAC_MAC_CTL1_DUPLEX_EN;
+	if (db->duplex)
+		reg_val |= EMAC_MAC_CTL1_DUPLEX_EN;
+	writel(reg_val, db->membase + EMAC_MAC_CTL1_REG);
+}
+
+static void emac_handle_link_change(struct net_device *dev)
+{
+	struct emac_board_info *db = netdev_priv(dev);
+	struct phy_device *phydev = dev->phydev;
+	unsigned long flags;
+	int status_change = 0;
+
+	if (phydev->link) {
+		if (db->speed != phydev->speed) {
+			spin_lock_irqsave(&db->lock, flags);
+			db->speed = phydev->speed;
+			emac_update_speed(dev);
+			spin_unlock_irqrestore(&db->lock, flags);
+			status_change = 1;
+		}
+
+		if (db->duplex != phydev->duplex) {
+			spin_lock_irqsave(&db->lock, flags);
+			db->duplex = phydev->duplex;
+			emac_update_duplex(dev);
+			spin_unlock_irqrestore(&db->lock, flags);
+			status_change = 1;
+		}
+	}
+
+	if (phydev->link != db->link) {
+		if (!phydev->link) {
+			db->speed = 0;
+			db->duplex = -1;
+		}
+		db->link = phydev->link;
+
+		status_change = 1;
+	}
+
+	if (status_change)
+		phy_print_status(phydev);
+}
+
+static int emac_mdio_probe(struct net_device *dev)
+{
+	struct emac_board_info *db = netdev_priv(dev);
+	struct phy_device *phydev;
+
+	/* to-do: PHY interrupts are currently not supported */
+
+	/* attach the mac to the phy */
+	phydev = of_phy_connect(db->ndev, db->phy_node,
+				&emac_handle_link_change, 0,
+				db->phy_interface);
+	if (!phydev) {
+		netdev_err(db->ndev, "could not find the PHY\n");
+		return -ENODEV;
+	}
+
+	/* mask with MAC supported features */
+	phy_set_max_speed(phydev, SPEED_100);
+
+	db->link = 0;
+	db->speed = 0;
+	db->duplex = -1;
+
+	return 0;
+}
+
+static void emac_mdio_remove(struct net_device *dev)
+{
+	phy_disconnect(dev->phydev);
+}
+
+static void emac_reset(struct emac_board_info *db)
+{
+	dev_dbg(db->dev, "resetting device\n");
+
+	/* RESET device */
+	writel(0, db->membase + EMAC_CTL_REG);
+	udelay(200);
+	writel(EMAC_CTL_RESET, db->membase + EMAC_CTL_REG);
+	udelay(200);
+}
+
+static void emac_outblk_32bit(void __iomem *reg, void *data, int count)
+{
+	writesl(reg, data, round_up(count, 4) / 4);
+}
+
+static void emac_inblk_32bit(void __iomem *reg, void *data, int count)
+{
+	readsl(reg, data, round_up(count, 4) / 4);
+}
+
+static struct emac_dma_req *
+emac_alloc_dma_req(struct emac_board_info *db,
+		   struct dma_async_tx_descriptor *desc, struct sk_buff *skb,
+		   dma_addr_t rxbuf, int count)
+{
+	struct emac_dma_req *req;
+
+	req = kzalloc(sizeof(struct emac_dma_req), GFP_ATOMIC);
+	if (!req)
+		return NULL;
+
+	req->db = db;
+	req->desc = desc;
+	req->skb = skb;
+	req->rxbuf = rxbuf;
+	req->count = count;
+	return req;
+}
+
+static void emac_free_dma_req(struct emac_dma_req *req)
+{
+	kfree(req);
+}
+
+static void emac_dma_done_callback(void *arg)
+{
+	struct emac_dma_req *req = arg;
+	struct emac_board_info *db = req->db;
+	struct sk_buff *skb = req->skb;
+	struct net_device *dev = db->ndev;
+	int rxlen = req->count;
+	u32 reg_val;
+
+	dma_unmap_single(db->dev, req->rxbuf, rxlen, DMA_FROM_DEVICE);
+
+	skb->protocol = eth_type_trans(skb, dev);
+	netif_rx(skb);
+	dev->stats.rx_bytes += rxlen;
+	/* Pass to upper layer */
+	dev->stats.rx_packets++;
+
+	/* re enable cpu receive */
+	reg_val = readl(db->membase + EMAC_RX_CTL_REG);
+	reg_val &= ~EMAC_RX_CTL_DMA_EN;
+	writel(reg_val, db->membase + EMAC_RX_CTL_REG);
+
+	/* re enable interrupt */
+	reg_val = readl(db->membase + EMAC_INT_CTL_REG);
+	reg_val |= EMAC_INT_CTL_RX_EN;
+	writel(reg_val, db->membase + EMAC_INT_CTL_REG);
+
+	db->emacrx_completed_flag = 1;
+	emac_free_dma_req(req);
+}
+
+static int emac_dma_inblk_32bit(struct emac_board_info *db,
+		struct sk_buff *skb, void *rdptr, int count)
+{
+	struct dma_async_tx_descriptor *desc;
+	dma_cookie_t cookie;
+	dma_addr_t rxbuf;
+	struct emac_dma_req *req;
+	int ret = 0;
+
+	rxbuf = dma_map_single(db->dev, rdptr, count, DMA_FROM_DEVICE);
+	ret = dma_mapping_error(db->dev, rxbuf);
+	if (ret) {
+		dev_err(db->dev, "dma mapping error.\n");
+		return ret;
+	}
+
+	desc = dmaengine_prep_slave_single(db->rx_chan, rxbuf, count,
+					   DMA_DEV_TO_MEM,
+					   DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+	if (!desc) {
+		dev_err(db->dev, "prepare slave single failed\n");
+		ret = -ENOMEM;
+		goto prepare_err;
+	}
+
+	req = emac_alloc_dma_req(db, desc, skb, rxbuf, count);
+	if (!req) {
+		dev_err(db->dev, "alloc emac dma req error.\n");
+		ret = -ENOMEM;
+		goto alloc_req_err;
+	}
+
+	desc->callback_param = req;
+	desc->callback = emac_dma_done_callback;
+
+	cookie = dmaengine_submit(desc);
+	ret = dma_submit_error(cookie);
+	if (ret) {
+		dev_err(db->dev, "dma submit error.\n");
+		goto submit_err;
+	}
+
+	dma_async_issue_pending(db->rx_chan);
+	return ret;
+
+submit_err:
+	emac_free_dma_req(req);
+
+alloc_req_err:
+	dmaengine_desc_free(desc);
+
+prepare_err:
+	dma_unmap_single(db->dev, rxbuf, count, DMA_FROM_DEVICE);
+	return ret;
+}
+
+/* ethtool ops */
+static void emac_get_drvinfo(struct net_device *dev,
+			      struct ethtool_drvinfo *info)
+{
+	strscpy(info->driver, DRV_NAME, sizeof(info->driver));
+	strscpy(info->bus_info, dev_name(&dev->dev), sizeof(info->bus_info));
+}
+
+static u32 emac_get_msglevel(struct net_device *dev)
+{
+	struct emac_board_info *db = netdev_priv(dev);
+
+	return db->msg_enable;
+}
+
+static void emac_set_msglevel(struct net_device *dev, u32 value)
+{
+	struct emac_board_info *db = netdev_priv(dev);
+
+	db->msg_enable = value;
+}
+
+static const struct ethtool_ops emac_ethtool_ops = {
+	.get_drvinfo	= emac_get_drvinfo,
+	.get_link	= ethtool_op_get_link,
+	.get_link_ksettings = phy_ethtool_get_link_ksettings,
+	.set_link_ksettings = phy_ethtool_set_link_ksettings,
+	.get_msglevel	= emac_get_msglevel,
+	.set_msglevel	= emac_set_msglevel,
+};
+
+static unsigned int emac_setup(struct net_device *ndev)
+{
+	struct emac_board_info *db = netdev_priv(ndev);
+	unsigned int reg_val;
+
+	/* set up TX */
+	reg_val = readl(db->membase + EMAC_TX_MODE_REG);
+
+	writel(reg_val | EMAC_TX_MODE_ABORTED_FRAME_EN,
+		db->membase + EMAC_TX_MODE_REG);
+
+	/* set MAC */
+	/* set MAC CTL0 */
+	reg_val = readl(db->membase + EMAC_MAC_CTL0_REG);
+	writel(reg_val | EMAC_MAC_CTL0_RX_FLOW_CTL_EN |
+		EMAC_MAC_CTL0_TX_FLOW_CTL_EN,
+		db->membase + EMAC_MAC_CTL0_REG);
+
+	/* set MAC CTL1 */
+	reg_val = readl(db->membase + EMAC_MAC_CTL1_REG);
+	reg_val |= EMAC_MAC_CTL1_LEN_CHECK_EN;
+	reg_val |= EMAC_MAC_CTL1_CRC_EN;
+	reg_val |= EMAC_MAC_CTL1_PAD_EN;
+	writel(reg_val, db->membase + EMAC_MAC_CTL1_REG);
+
+	/* set up IPGT */
+	writel(EMAC_MAC_IPGT_FULL_DUPLEX, db->membase + EMAC_MAC_IPGT_REG);
+
+	/* set up IPGR */
+	writel((EMAC_MAC_IPGR_IPG1 << 8) | EMAC_MAC_IPGR_IPG2,
+		db->membase + EMAC_MAC_IPGR_REG);
+
+	/* set up Collison window */
+	writel((EMAC_MAC_CLRT_COLLISION_WINDOW << 8) | EMAC_MAC_CLRT_RM,
+		db->membase + EMAC_MAC_CLRT_REG);
+
+	/* set up Max Frame Length */
+	writel(EMAC_MAX_FRAME_LEN,
+		db->membase + EMAC_MAC_MAXF_REG);
+
+	return 0;
+}
+
+static void emac_set_rx_mode(struct net_device *ndev)
+{
+	struct emac_board_info *db = netdev_priv(ndev);
+	unsigned int reg_val;
+
+	/* set up RX */
+	reg_val = readl(db->membase + EMAC_RX_CTL_REG);
+
+	if (ndev->flags & IFF_PROMISC)
+		reg_val |= EMAC_RX_CTL_PASS_ALL_EN;
+	else
+		reg_val &= ~EMAC_RX_CTL_PASS_ALL_EN;
+
+	writel(reg_val | EMAC_RX_CTL_PASS_LEN_OOR_EN |
+		EMAC_RX_CTL_ACCEPT_UNICAST_EN | EMAC_RX_CTL_DA_FILTER_EN |
+		EMAC_RX_CTL_ACCEPT_MULTICAST_EN |
+		EMAC_RX_CTL_ACCEPT_BROADCAST_EN,
+		db->membase + EMAC_RX_CTL_REG);
+}
+
+static unsigned int emac_powerup(struct net_device *ndev)
+{
+	struct emac_board_info *db = netdev_priv(ndev);
+	unsigned int reg_val;
+
+	/* initial EMAC */
+	/* flush RX FIFO */
+	reg_val = readl(db->membase + EMAC_RX_CTL_REG);
+	reg_val |= EMAC_RX_CTL_FLUSH_FIFO;
+	writel(reg_val, db->membase + EMAC_RX_CTL_REG);
+	udelay(1);
+
+	/* initial MAC */
+	/* soft reset MAC */
+	reg_val = readl(db->membase + EMAC_MAC_CTL0_REG);
+	reg_val &= ~EMAC_MAC_CTL0_SOFT_RESET;
+	writel(reg_val, db->membase + EMAC_MAC_CTL0_REG);
+
+	/* set MII clock */
+	reg_val = readl(db->membase + EMAC_MAC_MCFG_REG);
+	reg_val &= ~EMAC_MAC_MCFG_MII_CLKD_MASK;
+	reg_val |= EMAC_MAC_MCFG_MII_CLKD_72;
+	writel(reg_val, db->membase + EMAC_MAC_MCFG_REG);
+
+	/* clear RX counter */
+	writel(0x0, db->membase + EMAC_RX_FBC_REG);
+
+	/* disable all interrupt and clear interrupt status */
+	writel(0, db->membase + EMAC_INT_CTL_REG);
+	reg_val = readl(db->membase + EMAC_INT_STA_REG);
+	writel(reg_val, db->membase + EMAC_INT_STA_REG);
+
+	udelay(1);
+
+	/* set up EMAC */
+	emac_setup(ndev);
+
+	/* set mac_address to chip */
+	writel(ndev->dev_addr[0] << 16 | ndev->dev_addr[1] << 8 | ndev->
+	       dev_addr[2], db->membase + EMAC_MAC_A1_REG);
+	writel(ndev->dev_addr[3] << 16 | ndev->dev_addr[4] << 8 | ndev->
+	       dev_addr[5], db->membase + EMAC_MAC_A0_REG);
+
+	mdelay(1);
+
+	return 0;
+}
+
+static int emac_set_mac_address(struct net_device *dev, void *p)
+{
+	struct sockaddr *addr = p;
+	struct emac_board_info *db = netdev_priv(dev);
+
+	if (netif_running(dev))
+		return -EBUSY;
+
+	eth_hw_addr_set(dev, addr->sa_data);
+
+	writel(dev->dev_addr[0] << 16 | dev->dev_addr[1] << 8 | dev->
+	       dev_addr[2], db->membase + EMAC_MAC_A1_REG);
+	writel(dev->dev_addr[3] << 16 | dev->dev_addr[4] << 8 | dev->
+	       dev_addr[5], db->membase + EMAC_MAC_A0_REG);
+
+	return 0;
+}
+
+/* Initialize emac board */
+static void emac_init_device(struct net_device *dev)
+{
+	struct emac_board_info *db = netdev_priv(dev);
+	unsigned long flags;
+	unsigned int reg_val;
+
+	spin_lock_irqsave(&db->lock, flags);
+
+	emac_update_speed(dev);
+	emac_update_duplex(dev);
+
+	/* enable RX/TX */
+	reg_val = readl(db->membase + EMAC_CTL_REG);
+	writel(reg_val | EMAC_CTL_RESET | EMAC_CTL_TX_EN | EMAC_CTL_RX_EN,
+		db->membase + EMAC_CTL_REG);
+
+	/* enable RX/TX0/RX Hlevel interrup */
+	reg_val = readl(db->membase + EMAC_INT_CTL_REG);
+	reg_val |= (EMAC_INT_CTL_TX_EN | EMAC_INT_CTL_TX_ABRT_EN | EMAC_INT_CTL_RX_EN);
+	writel(reg_val, db->membase + EMAC_INT_CTL_REG);
+
+	spin_unlock_irqrestore(&db->lock, flags);
+}
+
+/* Our watchdog timed out. Called by the networking layer */
+static void emac_timeout(struct net_device *dev, unsigned int txqueue)
+{
+	struct emac_board_info *db = netdev_priv(dev);
+	unsigned long flags;
+
+	if (netif_msg_timer(db))
+		dev_err(db->dev, "tx time out.\n");
+
+	/* Save previous register address */
+	spin_lock_irqsave(&db->lock, flags);
+
+	netif_stop_queue(dev);
+	emac_reset(db);
+	emac_init_device(dev);
+	/* We can accept TX packets again */
+	netif_trans_update(dev);
+	netif_wake_queue(dev);
+
+	/* Restore previous register address */
+	spin_unlock_irqrestore(&db->lock, flags);
+}
+
+/* Hardware start transmission.
+ * Send a packet to media from the upper layer.
+ */
+static netdev_tx_t emac_start_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	struct emac_board_info *db = netdev_priv(dev);
+	unsigned long channel;
+	unsigned long flags;
+
+	channel = db->tx_fifo_stat & 3;
+	if (channel == 3)
+		return NETDEV_TX_BUSY;
+
+	channel = (channel == 1 ? 1 : 0);
+
+	spin_lock_irqsave(&db->lock, flags);
+
+	writel(channel, db->membase + EMAC_TX_INS_REG);
+
+	emac_outblk_32bit(db->membase + EMAC_TX_IO_DATA_REG,
+			skb->data, skb->len);
+	dev->stats.tx_bytes += skb->len;
+
+	db->tx_fifo_stat |= 1 << channel;
+	/* TX control: First packet immediately send, second packet queue */
+	if (channel == 0) {
+		/* set TX len */
+		writel(skb->len, db->membase + EMAC_TX_PL0_REG);
+		/* start translate from fifo to phy */
+		writel(readl(db->membase + EMAC_TX_CTL0_REG) | 1,
+		       db->membase + EMAC_TX_CTL0_REG);
+
+		/* save the time stamp */
+		netif_trans_update(dev);
+	} else if (channel == 1) {
+		/* set TX len */
+		writel(skb->len, db->membase + EMAC_TX_PL1_REG);
+		/* start translate from fifo to phy */
+		writel(readl(db->membase + EMAC_TX_CTL1_REG) | 1,
+		       db->membase + EMAC_TX_CTL1_REG);
+
+		/* save the time stamp */
+		netif_trans_update(dev);
+	}
+
+	if ((db->tx_fifo_stat & 3) == 3) {
+		/* Second packet */
+		netif_stop_queue(dev);
+	}
+
+	spin_unlock_irqrestore(&db->lock, flags);
+
+	/* free this SKB */
+	dev_consume_skb_any(skb);
+
+	return NETDEV_TX_OK;
+}
+
+/* EMAC interrupt handler
+ * receive the packet to upper layer, free the transmitted packet
+ */
+static void emac_tx_done(struct net_device *dev, struct emac_board_info *db,
+			  unsigned int tx_status)
+{
+	/* One packet sent complete */
+	db->tx_fifo_stat &= ~(tx_status & 3);
+	if (3 == (tx_status & 3))
+		dev->stats.tx_packets += 2;
+	else
+		dev->stats.tx_packets++;
+
+	if (netif_msg_tx_done(db))
+		dev_dbg(db->dev, "tx done, NSR %02x\n", tx_status);
+
+	netif_wake_queue(dev);
+}
+
+/* Received a packet and pass to upper layer
+ */
+static void emac_rx(struct net_device *dev)
+{
+	struct emac_board_info *db = netdev_priv(dev);
+	struct sk_buff *skb;
+	u8 *rdptr;
+	bool good_packet;
+	unsigned int reg_val;
+	u32 rxhdr, rxstatus, rxcount, rxlen;
+
+	/* Check packet ready or not */
+	while (1) {
+		/* race warning: the first packet might arrive with
+		 * the interrupts disabled, but the second will fix
+		 * it
+		 */
+		rxcount = readl(db->membase + EMAC_RX_FBC_REG);
+
+		if (netif_msg_rx_status(db))
+			dev_dbg(db->dev, "RXCount: %x\n", rxcount);
+
+		if (!rxcount) {
+			db->emacrx_completed_flag = 1;
+			reg_val = readl(db->membase + EMAC_INT_CTL_REG);
+			reg_val |= (EMAC_INT_CTL_TX_EN |
+					EMAC_INT_CTL_TX_ABRT_EN |
+					EMAC_INT_CTL_RX_EN);
+			writel(reg_val, db->membase + EMAC_INT_CTL_REG);
+
+			/* had one stuck? */
+			rxcount = readl(db->membase + EMAC_RX_FBC_REG);
+			if (!rxcount)
+				return;
+		}
+
+		reg_val = readl(db->membase + EMAC_RX_IO_DATA_REG);
+		if (netif_msg_rx_status(db))
+			dev_dbg(db->dev, "receive header: %x\n", reg_val);
+		if (reg_val != EMAC_UNDOCUMENTED_MAGIC) {
+			/* disable RX */
+			reg_val = readl(db->membase + EMAC_CTL_REG);
+			writel(reg_val & ~EMAC_CTL_RX_EN,
+			       db->membase + EMAC_CTL_REG);
+
+			/* Flush RX FIFO */
+			reg_val = readl(db->membase + EMAC_RX_CTL_REG);
+			writel(reg_val | (1 << 3),
+			       db->membase + EMAC_RX_CTL_REG);
+
+			do {
+				reg_val = readl(db->membase + EMAC_RX_CTL_REG);
+			} while (reg_val & (1 << 3));
+
+			/* enable RX */
+			reg_val = readl(db->membase + EMAC_CTL_REG);
+			writel(reg_val | EMAC_CTL_RX_EN,
+			       db->membase + EMAC_CTL_REG);
+			reg_val = readl(db->membase + EMAC_INT_CTL_REG);
+			reg_val |= (EMAC_INT_CTL_TX_EN |
+					EMAC_INT_CTL_TX_ABRT_EN |
+					EMAC_INT_CTL_RX_EN);
+			writel(reg_val, db->membase + EMAC_INT_CTL_REG);
+
+			db->emacrx_completed_flag = 1;
+
+			return;
+		}
+
+		/* A packet ready now  & Get status/length */
+		good_packet = true;
+
+		rxhdr = readl(db->membase + EMAC_RX_IO_DATA_REG);
+
+		if (netif_msg_rx_status(db))
+			dev_dbg(db->dev, "rxhdr: %x\n", *((int *)(&rxhdr)));
+
+		rxlen = EMAC_RX_IO_DATA_LEN(rxhdr);
+		rxstatus = EMAC_RX_IO_DATA_STATUS(rxhdr);
+
+		if (netif_msg_rx_status(db))
+			dev_dbg(db->dev, "RX: status %02x, length %04x\n",
+				rxstatus, rxlen);
+
+		/* Packet Status check */
+		if (rxlen < 0x40) {
+			good_packet = false;
+			if (netif_msg_rx_err(db))
+				dev_dbg(db->dev, "RX: Bad Packet (runt)\n");
+		}
+
+		if (unlikely(!(rxstatus & EMAC_RX_IO_DATA_STATUS_OK))) {
+			good_packet = false;
+
+			if (rxstatus & EMAC_RX_IO_DATA_STATUS_CRC_ERR) {
+				if (netif_msg_rx_err(db))
+					dev_dbg(db->dev, "crc error\n");
+				dev->stats.rx_crc_errors++;
+			}
+
+			if (rxstatus & EMAC_RX_IO_DATA_STATUS_LEN_ERR) {
+				if (netif_msg_rx_err(db))
+					dev_dbg(db->dev, "length error\n");
+				dev->stats.rx_length_errors++;
+			}
+		}
+
+		/* Move data from EMAC */
+		if (good_packet) {
+			skb = netdev_alloc_skb(dev, rxlen + 4);
+			if (!skb)
+				continue;
+			skb_reserve(skb, 2);
+			rdptr = skb_put(skb, rxlen - 4);
+
+			/* Read received packet from RX SRAM */
+			if (netif_msg_rx_status(db))
+				dev_dbg(db->dev, "RxLen %x\n", rxlen);
+
+			if (rxlen >= dev->mtu && db->rx_chan) {
+				reg_val = readl(db->membase + EMAC_RX_CTL_REG);
+				reg_val |= EMAC_RX_CTL_DMA_EN;
+				writel(reg_val, db->membase + EMAC_RX_CTL_REG);
+				if (!emac_dma_inblk_32bit(db, skb, rdptr, rxlen))
+					break;
+
+				/* re enable cpu receive. then try to receive by emac_inblk_32bit */
+				reg_val = readl(db->membase + EMAC_RX_CTL_REG);
+				reg_val &= ~EMAC_RX_CTL_DMA_EN;
+				writel(reg_val, db->membase + EMAC_RX_CTL_REG);
+			}
+
+			emac_inblk_32bit(db->membase + EMAC_RX_IO_DATA_REG,
+					rdptr, rxlen);
+			dev->stats.rx_bytes += rxlen;
+
+			/* Pass to upper layer */
+			skb->protocol = eth_type_trans(skb, dev);
+			netif_rx(skb);
+			dev->stats.rx_packets++;
+		}
+	}
+}
+
+static irqreturn_t emac_interrupt(int irq, void *dev_id)
+{
+	struct net_device *dev = dev_id;
+	struct emac_board_info *db = netdev_priv(dev);
+	int int_status;
+	unsigned int reg_val;
+
+	/* A real interrupt coming */
+
+	spin_lock(&db->lock);
+
+	/* Disable all interrupts */
+	writel(0, db->membase + EMAC_INT_CTL_REG);
+
+	/* Got EMAC interrupt status */
+	/* Got ISR */
+	int_status = readl(db->membase + EMAC_INT_STA_REG);
+	/* Clear ISR status */
+	writel(int_status, db->membase + EMAC_INT_STA_REG);
+
+	if (netif_msg_intr(db))
+		dev_dbg(db->dev, "emac interrupt %02x\n", int_status);
+
+	/* Received the coming packet */
+	if ((int_status & 0x100) && (db->emacrx_completed_flag == 1)) {
+		/* carrier lost */
+		db->emacrx_completed_flag = 0;
+		emac_rx(dev);
+	}
+
+	/* Transmit Interrupt check */
+	if (int_status & EMAC_INT_STA_TX_COMPLETE)
+		emac_tx_done(dev, db, int_status);
+
+	if (int_status & EMAC_INT_STA_TX_ABRT)
+		netdev_info(dev, " ab : %x\n", int_status);
+
+	/* Re-enable interrupt mask */
+	if (db->emacrx_completed_flag == 1) {
+		reg_val = readl(db->membase + EMAC_INT_CTL_REG);
+		reg_val |= (EMAC_INT_CTL_TX_EN | EMAC_INT_CTL_TX_ABRT_EN | EMAC_INT_CTL_RX_EN);
+		writel(reg_val, db->membase + EMAC_INT_CTL_REG);
+	} else {
+		reg_val = readl(db->membase + EMAC_INT_CTL_REG);
+		reg_val |= (EMAC_INT_CTL_TX_EN | EMAC_INT_CTL_TX_ABRT_EN);
+		writel(reg_val, db->membase + EMAC_INT_CTL_REG);
+	}
+
+	spin_unlock(&db->lock);
+
+	return IRQ_HANDLED;
+}
+
+#ifdef CONFIG_NET_POLL_CONTROLLER
+/*
+ * Used by netconsole
+ */
+static void emac_poll_controller(struct net_device *dev)
+{
+	disable_irq(dev->irq);
+	emac_interrupt(dev->irq, dev);
+	enable_irq(dev->irq);
+}
+#endif
+
+/*  Open the interface.
+ *  The interface is opened whenever "ifconfig" actives it.
+ */
+static int emac_open(struct net_device *dev)
+{
+	struct emac_board_info *db = netdev_priv(dev);
+	int ret;
+
+	if (netif_msg_ifup(db))
+		dev_dbg(db->dev, "enabling %s\n", dev->name);
+
+	if (request_irq(dev->irq, &emac_interrupt, 0, dev->name, dev))
+		return -EAGAIN;
+
+	/* Initialize EMAC board */
+	emac_reset(db);
+	emac_init_device(dev);
+
+	ret = emac_mdio_probe(dev);
+	if (ret < 0) {
+		free_irq(dev->irq, dev);
+		netdev_err(dev, "cannot probe MDIO bus\n");
+		return ret;
+	}
+
+	phy_start(dev->phydev);
+	netif_start_queue(dev);
+
+	return 0;
+}
+
+static void emac_shutdown(struct net_device *dev)
+{
+	unsigned int reg_val;
+	struct emac_board_info *db = netdev_priv(dev);
+
+	/* Disable all interrupt */
+	writel(0, db->membase + EMAC_INT_CTL_REG);
+
+	/* clear interrupt status */
+	reg_val = readl(db->membase + EMAC_INT_STA_REG);
+	writel(reg_val, db->membase + EMAC_INT_STA_REG);
+
+	/* Disable RX/TX */
+	reg_val = readl(db->membase + EMAC_CTL_REG);
+	reg_val &= ~(EMAC_CTL_TX_EN | EMAC_CTL_RX_EN | EMAC_CTL_RESET);
+	writel(reg_val, db->membase + EMAC_CTL_REG);
+}
+
+/* Stop the interface.
+ * The interface is stopped when it is brought.
+ */
+static int emac_stop(struct net_device *ndev)
+{
+	struct emac_board_info *db = netdev_priv(ndev);
+
+	if (netif_msg_ifdown(db))
+		dev_dbg(db->dev, "shutting down %s\n", ndev->name);
+
+	netif_stop_queue(ndev);
+	netif_carrier_off(ndev);
+
+	phy_stop(ndev->phydev);
+
+	emac_mdio_remove(ndev);
+
+	emac_shutdown(ndev);
+
+	free_irq(ndev->irq, ndev);
+
+	return 0;
+}
+
+static const struct net_device_ops emac_netdev_ops = {
+	.ndo_open		= emac_open,
+	.ndo_stop		= emac_stop,
+	.ndo_start_xmit		= emac_start_xmit,
+	.ndo_tx_timeout		= emac_timeout,
+	.ndo_set_rx_mode	= emac_set_rx_mode,
+	.ndo_eth_ioctl		= phy_do_ioctl_running,
+	.ndo_validate_addr	= eth_validate_addr,
+	.ndo_set_mac_address	= emac_set_mac_address,
+#ifdef CONFIG_NET_POLL_CONTROLLER
+	.ndo_poll_controller	= emac_poll_controller,
+#endif
+};
+
+static int emac_configure_dma(struct emac_board_info *db)
+{
+	struct platform_device *pdev = db->pdev;
+	struct net_device *ndev = db->ndev;
+	struct dma_slave_config conf = {};
+	struct resource *regs;
+	int err = 0;
+
+	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!regs) {
+		netdev_err(ndev, "get io resource from device failed.\n");
+		err = -ENOMEM;
+		goto out_clear_chan;
+	}
+
+	netdev_info(ndev, "get io resource from device: %pa, size = %u\n",
+		    &regs->start, (unsigned int)resource_size(regs));
+	db->emac_rx_fifo = regs->start + EMAC_RX_IO_DATA_REG;
+
+	db->rx_chan = dma_request_chan(&pdev->dev, "rx");
+	if (IS_ERR(db->rx_chan)) {
+		netdev_err(ndev,
+			   "failed to request dma channel. dma is disabled\n");
+		err = PTR_ERR(db->rx_chan);
+		goto out_clear_chan;
+	}
+
+	conf.direction = DMA_DEV_TO_MEM;
+	conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+	conf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+	conf.src_addr = db->emac_rx_fifo;
+	conf.dst_maxburst = 4;
+	conf.src_maxburst = 4;
+	conf.device_fc = false;
+
+	err = dmaengine_slave_config(db->rx_chan, &conf);
+	if (err) {
+		netdev_err(ndev, "config dma slave failed\n");
+		err = -EINVAL;
+		goto out_slave_configure_err;
+	}
+
+	return err;
+
+out_slave_configure_err:
+	dma_release_channel(db->rx_chan);
+
+out_clear_chan:
+	db->rx_chan = NULL;
+	return err;
+}
+
+/* Search EMAC board, allocate space and register it
+ */
+static int emac_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct emac_board_info *db;
+	struct net_device *ndev;
+	int ret = 0;
+
+	ndev = alloc_etherdev(sizeof(struct emac_board_info));
+	if (!ndev) {
+		dev_err(&pdev->dev, "could not allocate device.\n");
+		return -ENOMEM;
+	}
+
+	SET_NETDEV_DEV(ndev, &pdev->dev);
+
+	db = netdev_priv(ndev);
+
+	db->dev = &pdev->dev;
+	db->ndev = ndev;
+	db->pdev = pdev;
+	db->msg_enable = netif_msg_init(debug, EMAC_DEFAULT_MSG_ENABLE);
+
+	spin_lock_init(&db->lock);
+
+	db->membase = of_iomap(np, 0);
+	if (!db->membase) {
+		dev_err(&pdev->dev, "failed to remap registers\n");
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	/* fill in parameters for net-dev structure */
+	ndev->base_addr = (unsigned long)db->membase;
+	ndev->irq = irq_of_parse_and_map(np, 0);
+	if (ndev->irq == -ENXIO) {
+		netdev_err(ndev, "No irq resource\n");
+		ret = ndev->irq;
+		goto out_iounmap;
+	}
+
+	if (emac_configure_dma(db))
+		netdev_info(ndev, "configure dma failed. disable dma.\n");
+
+	db->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(db->clk)) {
+		ret = PTR_ERR(db->clk);
+		goto out_dispose_mapping;
+	}
+
+	ret = clk_prepare_enable(db->clk);
+	if (ret) {
+		dev_err(&pdev->dev, "Error couldn't enable clock (%d)\n", ret);
+		goto out_dispose_mapping;
+	}
+
+	ret = sunxi_sram_claim(&pdev->dev);
+	if (ret) {
+		dev_err(&pdev->dev, "Error couldn't map SRAM to device\n");
+		goto out_clk_disable_unprepare;
+	}
+
+	db->phy_node = of_parse_phandle(np, "phy-handle", 0);
+	if (!db->phy_node)
+		db->phy_node = of_parse_phandle(np, "phy", 0);
+	if (!db->phy_node) {
+		dev_err(&pdev->dev, "no associated PHY\n");
+		ret = -ENODEV;
+		goto out_release_sram;
+	}
+
+	/* Read MAC-address from DT */
+	ret = of_get_ethdev_address(np, ndev);
+	if (ret) {
+		/* if the MAC address is invalid get a random one */
+		eth_hw_addr_random(ndev);
+		dev_warn(&pdev->dev, "using random MAC address %pM\n",
+			 ndev->dev_addr);
+	}
+
+	db->emacrx_completed_flag = 1;
+	emac_powerup(ndev);
+	emac_reset(db);
+
+	ndev->netdev_ops = &emac_netdev_ops;
+	ndev->watchdog_timeo = msecs_to_jiffies(watchdog);
+	ndev->ethtool_ops = &emac_ethtool_ops;
+
+	platform_set_drvdata(pdev, ndev);
+
+	/* Carrier starts down, phylib will bring it up */
+	netif_carrier_off(ndev);
+
+	ret = register_netdev(ndev);
+	if (ret) {
+		dev_err(&pdev->dev, "Registering netdev failed!\n");
+		ret = -ENODEV;
+		goto out_release_sram;
+	}
+
+	dev_info(&pdev->dev, "%s: at %p, IRQ %d MAC: %pM\n",
+		 ndev->name, db->membase, ndev->irq, ndev->dev_addr);
+
+	return 0;
+
+out_release_sram:
+	sunxi_sram_release(&pdev->dev);
+out_clk_disable_unprepare:
+	clk_disable_unprepare(db->clk);
+out_dispose_mapping:
+	irq_dispose_mapping(ndev->irq);
+	dma_release_channel(db->rx_chan);
+out_iounmap:
+	iounmap(db->membase);
+out:
+	dev_err(db->dev, "not found (%d).\n", ret);
+
+	free_netdev(ndev);
+
+	return ret;
+}
+
+static int emac_remove(struct platform_device *pdev)
+{
+	struct net_device *ndev = platform_get_drvdata(pdev);
+	struct emac_board_info *db = netdev_priv(ndev);
+
+	if (db->rx_chan) {
+		dmaengine_terminate_all(db->rx_chan);
+		dma_release_channel(db->rx_chan);
+	}
+
+	unregister_netdev(ndev);
+	sunxi_sram_release(&pdev->dev);
+	clk_disable_unprepare(db->clk);
+	irq_dispose_mapping(ndev->irq);
+	iounmap(db->membase);
+	free_netdev(ndev);
+
+	dev_dbg(&pdev->dev, "released and freed device\n");
+	return 0;
+}
+
+static int emac_suspend(struct platform_device *dev, pm_message_t state)
+{
+	struct net_device *ndev = platform_get_drvdata(dev);
+
+	netif_carrier_off(ndev);
+	netif_device_detach(ndev);
+	emac_shutdown(ndev);
+
+	return 0;
+}
+
+static int emac_resume(struct platform_device *dev)
+{
+	struct net_device *ndev = platform_get_drvdata(dev);
+	struct emac_board_info *db = netdev_priv(ndev);
+
+	emac_reset(db);
+	emac_init_device(ndev);
+	netif_device_attach(ndev);
+
+	return 0;
+}
+
+static const struct of_device_id emac_of_match[] = {
+	{.compatible = "allwinner,sun4i-a10-emac",},
+
+	/* Deprecated */
+	{.compatible = "allwinner,sun4i-emac",},
+	{},
+};
+
+MODULE_DEVICE_TABLE(of, emac_of_match);
+
+static struct platform_driver emac_driver = {
+	.driver = {
+		.name = "sun4i-emac",
+		.of_match_table = emac_of_match,
+	},
+	.probe = emac_probe,
+	.remove = emac_remove,
+	.suspend = emac_suspend,
+	.resume = emac_resume,
+};
+
+module_platform_driver(emac_driver);
+
+MODULE_AUTHOR("Stefan Roese <sr@denx.de>");
+MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
+MODULE_DESCRIPTION("Allwinner A10 emac network driver");
+MODULE_LICENSE("GPL");