Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / net / ethernet / allwinner / sun4i-emac.c
diff --git a/kernel/drivers/net/ethernet/allwinner/sun4i-emac.c b/kernel/drivers/net/ethernet/allwinner/sun4i-emac.c
new file mode 100644 (file)
index 0000000..bab01c8
--- /dev/null
@@ -0,0 +1,972 @@
+/*
+ * 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 "sun4i-emac.h"
+
+#define DRV_NAME               "sun4i-emac"
+#define DRV_VERSION            "1.02"
+
+#define EMAC_MAX_FRAME_LEN     0x0600
+
+/* 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;
+       struct sk_buff          *skb_last;
+       u16                     tx_fifo_stat;
+
+       int                     emacrx_completed_flag;
+
+       struct phy_device       *phy_dev;
+       struct device_node      *phy_node;
+       unsigned int            link;
+       unsigned int            speed;
+       unsigned int            duplex;
+
+       phy_interface_t         phy_interface;
+};
+
+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 &= ~(0x1 << 8);
+       if (db->speed == SPEED_100)
+               reg_val |= 1 << 8;
+       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 = db->phy_dev;
+       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);
+
+       /* to-do: PHY interrupts are currently not supported */
+
+       /* attach the mac to the phy */
+       db->phy_dev = of_phy_connect(db->ndev, db->phy_node,
+                                    &emac_handle_link_change, 0,
+                                    db->phy_interface);
+       if (!db->phy_dev) {
+               netdev_err(db->ndev, "could not find the PHY\n");
+               return -ENODEV;
+       }
+
+       /* mask with MAC supported features */
+       db->phy_dev->supported &= PHY_BASIC_FEATURES;
+       db->phy_dev->advertising = db->phy_dev->supported;
+
+       db->link = 0;
+       db->speed = 0;
+       db->duplex = -1;
+
+       return 0;
+}
+
+static void emac_mdio_remove(struct net_device *dev)
+{
+       struct emac_board_info *db = netdev_priv(dev);
+
+       phy_disconnect(db->phy_dev);
+       db->phy_dev = NULL;
+}
+
+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 int emac_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
+{
+       struct emac_board_info *dm = netdev_priv(dev);
+       struct phy_device *phydev = dm->phy_dev;
+
+       if (!netif_running(dev))
+               return -EINVAL;
+
+       if (!phydev)
+               return -ENODEV;
+
+       return phy_mii_ioctl(phydev, rq, cmd);
+}
+
+/* ethtool ops */
+static void emac_get_drvinfo(struct net_device *dev,
+                             struct ethtool_drvinfo *info)
+{
+       strlcpy(info->driver, DRV_NAME, sizeof(DRV_NAME));
+       strlcpy(info->version, DRV_VERSION, sizeof(DRV_VERSION));
+       strlcpy(info->bus_info, dev_name(&dev->dev), sizeof(info->bus_info));
+}
+
+static int emac_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
+{
+       struct emac_board_info *dm = netdev_priv(dev);
+       struct phy_device *phydev = dm->phy_dev;
+
+       if (!phydev)
+               return -ENODEV;
+
+       return phy_ethtool_gset(phydev, cmd);
+}
+
+static int emac_set_settings(struct net_device *dev, struct ethtool_cmd *cmd)
+{
+       struct emac_board_info *dm = netdev_priv(dev);
+       struct phy_device *phydev = dm->phy_dev;
+
+       if (!phydev)
+               return -ENODEV;
+
+       return phy_ethtool_sset(phydev, cmd);
+}
+
+static const struct ethtool_ops emac_ethtool_ops = {
+       .get_drvinfo    = emac_get_drvinfo,
+       .get_settings   = emac_get_settings,
+       .set_settings   = emac_set_settings,
+       .get_link       = ethtool_op_get_link,
+};
+
+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 |= 0x8;
+       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 &= (~(0xf << 2));
+       reg_val |= (0xD << 2);
+       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;
+
+       memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN);
+
+       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 |= (0xf << 0) | (0x01 << 8);
+       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)
+{
+       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 */
+       dev->trans_start = jiffies;
+       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 int 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 1;
+
+       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 */
+               dev->trans_start = jiffies;
+       } 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 */
+               dev->trans_start = jiffies;
+       }
+
+       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;
+       static int rxlen_last;
+       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 ((db->skb_last != NULL) && (rxlen_last > 0)) {
+                       dev->stats.rx_bytes += rxlen_last;
+
+                       /* Pass to upper layer */
+                       db->skb_last->protocol = eth_type_trans(db->skb_last,
+                                                               dev);
+                       netif_rx(db->skb_last);
+                       dev->stats.rx_packets++;
+                       db->skb_last = NULL;
+                       rxlen_last = 0;
+
+                       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 (!rxcount) {
+                       db->emacrx_completed_flag = 1;
+                       reg_val = readl(db->membase + EMAC_INT_CTL_REG);
+                       reg_val |= (0xf << 0) | (0x01 << 8);
+                       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 |= (0xf << 0) | (0x01 << 8);
+                       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;
+
+               emac_inblk_32bit(db->membase + EMAC_RX_IO_DATA_REG,
+                               &rxhdr, sizeof(rxhdr));
+
+               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 = (u8 *) 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);
+
+                       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 long flags;
+       unsigned int reg_val;
+
+       /* A real interrupt coming */
+
+       /* holders of db->lock must always block IRQs */
+       spin_lock_irqsave(&db->lock, flags);
+
+       /* 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 & (0x01 | 0x02))
+               emac_tx_done(dev, db, int_status);
+
+       if (int_status & (0x04 | 0x08))
+               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 |= (0xf << 0) | (0x01 << 8);
+               writel(reg_val, db->membase + EMAC_INT_CTL_REG);
+       }
+       spin_unlock_irqrestore(&db->lock, flags);
+
+       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(db->phy_dev);
+       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(db->phy_dev);
+
+       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_do_ioctl           = emac_ioctl,
+       .ndo_change_mtu         = eth_change_mtu,
+       .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
+};
+
+/* 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;
+       const char *mac_addr;
+
+       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);
+       memset(db, 0, sizeof(*db));
+
+       db->dev = &pdev->dev;
+       db->ndev = ndev;
+       db->pdev = pdev;
+
+       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;
+       }
+
+       db->clk = devm_clk_get(&pdev->dev, NULL);
+       if (IS_ERR(db->clk)) {
+               ret = PTR_ERR(db->clk);
+               goto out;
+       }
+
+       clk_prepare_enable(db->clk);
+
+       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;
+       }
+
+       /* Read MAC-address from DT */
+       mac_addr = of_get_mac_address(np);
+       if (mac_addr)
+               memcpy(ndev->dev_addr, mac_addr, ETH_ALEN);
+
+       /* Check if the MAC address is valid, if not get a random one */
+       if (!is_valid_ether_addr(ndev->dev_addr)) {
+               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;
+       }
+
+       dev_info(&pdev->dev, "%s: at %p, IRQ %d MAC: %pM\n",
+                ndev->name, db->membase, ndev->irq, ndev->dev_addr);
+
+       return 0;
+
+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);
+
+       unregister_netdev(ndev);
+       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");