/*  Silan SC92031 PCI Fast Ethernet Adapter driver
 *
 *  Based on vendor drivers:
 *  Silan Fast Ethernet Netcard Driver:
 *    MODULE_AUTHOR ("gaoyonghong");
 *    MODULE_DESCRIPTION ("SILAN Fast Ethernet driver");
 *    MODULE_LICENSE("GPL");
 *  8139D Fast Ethernet driver:
 *    (C) 2002 by gaoyonghong
 *    MODULE_AUTHOR ("gaoyonghong");
 *    MODULE_DESCRIPTION ("Rsltek 8139D PCI Fast Ethernet Adapter driver");
 *    MODULE_LICENSE("GPL");
 *  Both are almost identical and seem to be based on pci-skeleton.c
 *
 *  Rewritten for 2.6 by Cesar Eduardo Barros
 *
 *  A datasheet for this chip can be found at
 *  http://www.silan.com.cn/english/products/pdf/SC92031AY.pdf
 */

/* Note about set_mac_address: I don't know how to change the hardware
 * matching, so you need to enable IFF_PROMISC when using it.
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/pci.h>
#include <linux/dma-mapping.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/ethtool.h>
#include <linux/crc32.h>

#include <asm/irq.h>

#define SC92031_NAME "sc92031"

/* BAR 0 is MMIO, BAR 1 is PIO */
#ifndef SC92031_USE_BAR
#define SC92031_USE_BAR 0
#endif

/* Maximum number of multicast addresses to filter (vs. Rx-all-multicast). */
static int multicast_filter_limit = 64;
module_param(multicast_filter_limit, int, 0);
MODULE_PARM_DESC(multicast_filter_limit,
        "Maximum number of filtered multicast addresses");

static int media;
module_param(media, int, 0);
MODULE_PARM_DESC(media, "Media type (0x00 = autodetect,"
        " 0x01 = 10M half, 0x02 = 10M full,"
        " 0x04 = 100M half, 0x08 = 100M full)");

/* Size of the in-memory receive ring. */
#define  RX_BUF_LEN_IDX  3 /* 0==8K, 1==16K, 2==32K, 3==64K ,4==128K*/
#define  RX_BUF_LEN     (8192 << RX_BUF_LEN_IDX)

/* Number of Tx descriptor registers. */
#define  NUM_TX_DESC       4

/* max supported ethernet frame size -- must be at least (dev->mtu+14+4).*/
#define  MAX_ETH_FRAME_SIZE       1536

/* Size of the Tx bounce buffers -- must be at least (dev->mtu+14+4). */
#define  TX_BUF_SIZE       MAX_ETH_FRAME_SIZE
#define  TX_BUF_TOT_LEN    (TX_BUF_SIZE * NUM_TX_DESC)

/* The following settings are log_2(bytes)-4:  0 == 16 bytes .. 6==1024, 7==end of packet. */
#define  RX_FIFO_THRESH    7     /* Rx buffer level before first PCI xfer.  */

/* Time in jiffies before concluding the transmitter is hung. */
#define  TX_TIMEOUT     (4*HZ)

#define  SILAN_STATS_NUM    2    /* number of ETHTOOL_GSTATS */

/* media options */
#define  AUTOSELECT    0x00
#define  M10_HALF      0x01
#define  M10_FULL      0x02
#define  M100_HALF     0x04
#define  M100_FULL     0x08

 /* Symbolic offsets to registers. */
enum  silan_registers {
   Config0    = 0x00,         // Config0
   Config1    = 0x04,         // Config1
   RxBufWPtr  = 0x08,         // Rx buffer writer poiter
   IntrStatus = 0x0C,         // Interrupt status
   IntrMask   = 0x10,         // Interrupt mask
   RxbufAddr  = 0x14,         // Rx buffer start address
   RxBufRPtr  = 0x18,         // Rx buffer read pointer
   Txstatusall = 0x1C,        // Transmit status of all descriptors
   TxStatus0  = 0x20,         // Transmit status (Four 32bit registers).
   TxAddr0    = 0x30,         // Tx descriptors (also four 32bit).
   RxConfig   = 0x40,         // Rx configuration
   MAC0       = 0x44,         // Ethernet hardware address.
   MAR0       = 0x4C,         // Multicast filter.
   RxStatus0  = 0x54,         // Rx status
   TxConfig   = 0x5C,         // Tx configuration
   PhyCtrl    = 0x60,         // physical control
   FlowCtrlConfig = 0x64,     // flow control
   Miicmd0    = 0x68,         // Mii command0 register
   Miicmd1    = 0x6C,         // Mii command1 register
   Miistatus  = 0x70,         // Mii status register
   Timercnt   = 0x74,         // Timer counter register
   TimerIntr  = 0x78,         // Timer interrupt register
   PMConfig   = 0x7C,         // Power Manager configuration
   CRC0       = 0x80,         // Power Manager CRC ( Two 32bit regisers)
   Wakeup0    = 0x88,         // power Manager wakeup( Eight 64bit regiser)
   LSBCRC0    = 0xC8,         // power Manager LSBCRC(Two 32bit regiser)
   TestD0     = 0xD0,
   TestD4     = 0xD4,
   TestD8     = 0xD8,
};

#define MII_BMCR            0        // Basic mode control register
#define MII_BMSR            1        // Basic mode status register
#define MII_JAB             16
#define MII_OutputStatus    24

#define BMCR_FULLDPLX       0x0100    // Full duplex
#define BMCR_ANRESTART      0x0200    // Auto negotiation restart
#define BMCR_ANENABLE       0x1000    // Enable auto negotiation
#define BMCR_SPEED100       0x2000    // Select 100Mbps
#define BMSR_LSTATUS        0x0004    // Link status
#define PHY_16_JAB_ENB      0x1000
#define PHY_16_PORT_ENB     0x1

enum IntrStatusBits {
   LinkFail       = 0x80000000,
   LinkOK         = 0x40000000,
   TimeOut        = 0x20000000,
   RxOverflow     = 0x0040,
   RxOK           = 0x0020,
   TxOK           = 0x0001,
   IntrBits = LinkFail|LinkOK|TimeOut|RxOverflow|RxOK|TxOK,
};

enum TxStatusBits {
   TxCarrierLost = 0x20000000,
   TxAborted     = 0x10000000,
   TxOutOfWindow = 0x08000000,
   TxNccShift    = 22,
   EarlyTxThresShift = 16,
   TxStatOK      = 0x8000,
   TxUnderrun    = 0x4000,
   TxOwn         = 0x2000,
};

enum RxStatusBits {
   RxStatesOK   = 0x80000,
   RxBadAlign   = 0x40000,
   RxHugeFrame  = 0x20000,
   RxSmallFrame = 0x10000,
   RxCRCOK      = 0x8000,
   RxCrlFrame   = 0x4000,
   Rx_Broadcast = 0x2000,
   Rx_Multicast = 0x1000,
   RxAddrMatch  = 0x0800,
   MiiErr       = 0x0400,
};

enum RxConfigBits {
   RxFullDx    = 0x80000000,
   RxEnb       = 0x40000000,
   RxSmall     = 0x20000000,
   RxHuge      = 0x10000000,
   RxErr       = 0x08000000,
   RxAllphys   = 0x04000000,
   RxMulticast = 0x02000000,
   RxBroadcast = 0x01000000,
   RxLoopBack  = (1 << 23) | (1 << 22),
   LowThresholdShift  = 12,
   HighThresholdShift = 2,
};

enum TxConfigBits {
   TxFullDx       = 0x80000000,
   TxEnb          = 0x40000000,
   TxEnbPad       = 0x20000000,
   TxEnbHuge      = 0x10000000,
   TxEnbFCS       = 0x08000000,
   TxNoBackOff    = 0x04000000,
   TxEnbPrem      = 0x02000000,
   TxCareLostCrs  = 0x1000000,
   TxExdCollNum   = 0xf00000,
   TxDataRate     = 0x80000,
};

enum PhyCtrlconfigbits {
   PhyCtrlAne         = 0x80000000,
   PhyCtrlSpd100      = 0x40000000,
   PhyCtrlSpd10       = 0x20000000,
   PhyCtrlPhyBaseAddr = 0x1f000000,
   PhyCtrlDux         = 0x800000,
   PhyCtrlReset       = 0x400000,
};

enum FlowCtrlConfigBits {
   FlowCtrlFullDX = 0x80000000,
   FlowCtrlEnb    = 0x40000000,
};

enum Config0Bits {
   Cfg0_Reset  = 0x80000000,
   Cfg0_Anaoff = 0x40000000,
   Cfg0_LDPS   = 0x20000000,
};

enum Config1Bits {
   Cfg1_EarlyRx = 1 << 31,
   Cfg1_EarlyTx = 1 << 30,

   //rx buffer size
   Cfg1_Rcv8K   = 0x0,
   Cfg1_Rcv16K  = 0x1,
   Cfg1_Rcv32K  = 0x3,
   Cfg1_Rcv64K  = 0x7,
   Cfg1_Rcv128K = 0xf,
};

enum MiiCmd0Bits {
   Mii_Divider = 0x20000000,
   Mii_WRITE   = 0x400000,
   Mii_READ    = 0x200000,
   Mii_SCAN    = 0x100000,
   Mii_Tamod   = 0x80000,
   Mii_Drvmod  = 0x40000,
   Mii_mdc     = 0x20000,
   Mii_mdoen   = 0x10000,
   Mii_mdo     = 0x8000,
   Mii_mdi     = 0x4000,
};

enum MiiStatusBits {
    Mii_StatusBusy = 0x80000000,
};

enum PMConfigBits {
   PM_Enable  = 1 << 31,
   PM_LongWF  = 1 << 30,
   PM_Magic   = 1 << 29,
   PM_LANWake = 1 << 28,
   PM_LWPTN   = (1 << 27 | 1<< 26),
   PM_LinkUp  = 1 << 25,
   PM_WakeUp  = 1 << 24,
};

/* Locking rules:
 * priv->lock protects most of the fields of priv and most of the
 * hardware registers. It does not have to protect against softirqs
 * between sc92031_disable_interrupts and sc92031_enable_interrupts;
 * it also does not need to be used in ->open and ->stop while the
 * device interrupts are off.
 * Not having to protect against softirqs is very useful due to heavy
 * use of mdelay() at _sc92031_reset.
 * Functions prefixed with _sc92031_ must be called with the lock held;
 * functions prefixed with sc92031_ must be called without the lock held.
 * Use mmiowb() before unlocking if the hardware was written to.
 */

/* Locking rules for the interrupt:
 * - the interrupt and the tasklet never run at the same time
 * - neither run between sc92031_disable_interrupts and
 *   sc92031_enable_interrupt
 */

struct sc92031_priv {
        spinlock_t              lock;
        /* iomap.h cookie */
        void __iomem            *port_base;
        /* pci device structure */
        struct pci_dev          *pdev;
        /* tasklet */
        struct tasklet_struct   tasklet;

        /* CPU address of rx ring */
        void                    *rx_ring;
        /* PCI address of rx ring */
        dma_addr_t              rx_ring_dma_addr;
        /* PCI address of rx ring read pointer */
        dma_addr_t              rx_ring_tail;

        /* tx ring write index */
        unsigned                tx_head;
        /* tx ring read index */
        unsigned                tx_tail;
        /* CPU address of tx bounce buffer */
        void                    *tx_bufs;
        /* PCI address of tx bounce buffer */
        dma_addr_t              tx_bufs_dma_addr;

        /* copies of some hardware registers */
        u32                     intr_status;
        atomic_t                intr_mask;
        u32                     rx_config;
        u32                     tx_config;
        u32                     pm_config;

        /* copy of some flags from dev->flags */
        unsigned int            mc_flags;

        /* for ETHTOOL_GSTATS */
        u64                     tx_timeouts;
        u64                     rx_loss;

        /* for dev->get_stats */
        long                    rx_value;
};

/* I don't know which registers can be safely read; however, I can guess
 * MAC0 is one of them. */
static inline void _sc92031_dummy_read(void __iomem *port_base)
{
        ioread32(port_base + MAC0);
}

static u32 _sc92031_mii_wait(void __iomem *port_base)
{
        u32 mii_status;

        do {
                udelay(10);
                mii_status = ioread32(port_base + Miistatus);
        } while (mii_status & Mii_StatusBusy);

        return mii_status;
}

static u32 _sc92031_mii_cmd(void __iomem *port_base, u32 cmd0, u32 cmd1)
{
        iowrite32(Mii_Divider, port_base + Miicmd0);

        _sc92031_mii_wait(port_base);

        iowrite32(cmd1, port_base + Miicmd1);
        iowrite32(Mii_Divider | cmd0, port_base + Miicmd0);

        return _sc92031_mii_wait(port_base);
}

static void _sc92031_mii_scan(void __iomem *port_base)
{
        _sc92031_mii_cmd(port_base, Mii_SCAN, 0x1 << 6);
}

static u16 _sc92031_mii_read(void __iomem *port_base, unsigned reg)
{
        return _sc92031_mii_cmd(port_base, Mii_READ, reg << 6) >> 13;
}

static void _sc92031_mii_write(void __iomem *port_base, unsigned reg, u16 val)
{
        _sc92031_mii_cmd(port_base, Mii_WRITE, (reg << 6) | ((u32)val << 11));
}

static void sc92031_disable_interrupts(struct net_device *dev)
{
        struct sc92031_priv *priv = netdev_priv(dev);
        void __iomem *port_base = priv->port_base;

        /* tell the tasklet/interrupt not to enable interrupts */
        atomic_set(&priv->intr_mask, 0);
        wmb();

        /* stop interrupts */
        iowrite32(0, port_base + IntrMask);
        _sc92031_dummy_read(port_base);
        mmiowb();

        /* wait for any concurrent interrupt/tasklet to finish */
        synchronize_irq(dev->irq);
        tasklet_disable(&priv->tasklet);
}

static void sc92031_enable_interrupts(struct net_device *dev)
{
        struct sc92031_priv *priv = netdev_priv(dev);
        void __iomem *port_base = priv->port_base;

        tasklet_enable(&priv->tasklet);

        atomic_set(&priv->intr_mask, IntrBits);
        wmb();

        iowrite32(IntrBits, port_base + IntrMask);
        mmiowb();
}

static void _sc92031_disable_tx_rx(struct net_device *dev)
{
        struct sc92031_priv *priv = netdev_priv(dev);
        void __iomem *port_base = priv->port_base;

        priv->rx_config &= ~RxEnb;
        priv->tx_config &= ~TxEnb;
        iowrite32(priv->rx_config, port_base + RxConfig);
        iowrite32(priv->tx_config, port_base + TxConfig);
}

static void _sc92031_enable_tx_rx(struct net_device *dev)
{
        struct sc92031_priv *priv = netdev_priv(dev);
        void __iomem *port_base = priv->port_base;

        priv->rx_config |= RxEnb;
        priv->tx_config |= TxEnb;
        iowrite32(priv->rx_config, port_base + RxConfig);
        iowrite32(priv->tx_config, port_base + TxConfig);
}

static void _sc92031_tx_clear(struct net_device *dev)
{
        struct sc92031_priv *priv = netdev_priv(dev);

        while (priv->tx_head - priv->tx_tail > 0) {
                priv->tx_tail++;
                dev->stats.tx_dropped++;
        }
        priv->tx_head = priv->tx_tail = 0;
}

static void _sc92031_set_mar(struct net_device *dev)
{
        struct sc92031_priv *priv = netdev_priv(dev);
        void __iomem *port_base = priv->port_base;
        u32 mar0 = 0, mar1 = 0;

        if ((dev->flags & IFF_PROMISC)
                        || dev->mc_count > multicast_filter_limit
                        || (dev->flags & IFF_ALLMULTI))
                mar0 = mar1 = 0xffffffff;
        else if (dev->flags & IFF_MULTICAST) {
                struct dev_mc_list *mc_list;

                for (mc_list = dev->mc_list; mc_list; mc_list = mc_list->next) {
                        u32 crc;
                        unsigned bit = 0;

                        crc = ~ether_crc(ETH_ALEN, mc_list->dmi_addr);
                        crc >>= 24;

                        if (crc & 0x01) bit |= 0x02;
                        if (crc & 0x02) bit |= 0x01;
                        if (crc & 0x10) bit |= 0x20;
                        if (crc & 0x20) bit |= 0x10;
                        if (crc & 0x40) bit |= 0x08;
                        if (crc & 0x80) bit |= 0x04;

                        if (bit > 31)
                                mar0 |= 0x1 << (bit - 32);
                        else
                                mar1 |= 0x1 << bit;
                }
        }

        iowrite32(mar0, port_base + MAR0);
        iowrite32(mar1, port_base + MAR0 + 4);
}

static void _sc92031_set_rx_config(struct net_device *dev)
{
        struct sc92031_priv *priv = netdev_priv(dev);
        void __iomem *port_base = priv->port_base;
        unsigned int old_mc_flags;
        u32 rx_config_bits = 0;

        old_mc_flags = priv->mc_flags;

        if (dev->flags & IFF_PROMISC)
                rx_config_bits |= RxSmall | RxHuge | RxErr | RxBroadcast
                                | RxMulticast | RxAllphys;

        if (dev->flags & (IFF_ALLMULTI | IFF_MULTICAST))
                rx_config_bits |= RxMulticast;

        if (dev->flags & IFF_BROADCAST)
                rx_config_bits |= RxBroadcast;

        priv->rx_config &= ~(RxSmall | RxHuge | RxErr | RxBroadcast
                        | RxMulticast | RxAllphys);
        priv->rx_config |= rx_config_bits;

        priv->mc_flags = dev->flags & (IFF_PROMISC | IFF_ALLMULTI
                        | IFF_MULTICAST | IFF_BROADCAST);

        if (netif_carrier_ok(dev) && priv->mc_flags != old_mc_flags)
                iowrite32(priv->rx_config, port_base + RxConfig);
}

static bool _sc92031_check_media(struct net_device *dev)
{
        struct sc92031_priv *priv = netdev_priv(dev);
        void __iomem *port_base = priv->port_base;
        u16 bmsr;

        bmsr = _sc92031_mii_read(port_base, MII_BMSR);
        rmb();
        if (bmsr & BMSR_LSTATUS) {
                bool speed_100, duplex_full;
                u32 flow_ctrl_config = 0;
                u16 output_status = _sc92031_mii_read(port_base,
                                MII_OutputStatus);
                _sc92031_mii_scan(port_base);

                speed_100 = output_status & 0x2;
                duplex_full = output_status & 0x4;

                /* Initial Tx/Rx configuration */
                priv->rx_config = (0x40 << LowThresholdShift) | (0x1c0 << HighThresholdShift);
                priv->tx_config = 0x48800000;

                /* NOTE: vendor driver had dead code here to enable tx padding */

                if (!speed_100)
                        priv->tx_config |= 0x80000;

                // configure rx mode
                _sc92031_set_rx_config(dev);

                if (duplex_full) {
                        priv->rx_config |= RxFullDx;
                        priv->tx_config |= TxFullDx;
                        flow_ctrl_config = FlowCtrlFullDX | FlowCtrlEnb;
                } else {
                        priv->rx_config &= ~RxFullDx;
                        priv->tx_config &= ~TxFullDx;
                }

                _sc92031_set_mar(dev);
                _sc92031_set_rx_config(dev);
                _sc92031_enable_tx_rx(dev);
                iowrite32(flow_ctrl_config, port_base + FlowCtrlConfig);

                netif_carrier_on(dev);

                if (printk_ratelimit())
                        printk(KERN_INFO "%s: link up, %sMbps, %s-duplex\n",
                                dev->name,
                                speed_100 ? "100" : "10",
                                duplex_full ? "full" : "half");
                return true;
        } else {
                _sc92031_mii_scan(port_base);

                netif_carrier_off(dev);

                _sc92031_disable_tx_rx(dev);

                if (printk_ratelimit())
                        printk(KERN_INFO "%s: link down\n", dev->name);
                return false;
        }
}

static void _sc92031_phy_reset(struct net_device *dev)
{
        struct sc92031_priv *priv = netdev_priv(dev);
        void __iomem *port_base = priv->port_base;
        u32 phy_ctrl;

        phy_ctrl = ioread32(port_base + PhyCtrl);
        phy_ctrl &= ~(PhyCtrlDux | PhyCtrlSpd100 | PhyCtrlSpd10);
        phy_ctrl |= PhyCtrlAne | PhyCtrlReset;

        switch (media) {
        default:
        case AUTOSELECT:
                phy_ctrl |= PhyCtrlDux | PhyCtrlSpd100 | PhyCtrlSpd10;
                break;
        case M10_HALF:
                phy_ctrl |= PhyCtrlSpd10;
                break;
        case M10_FULL:
                phy_ctrl |= PhyCtrlDux | PhyCtrlSpd10;
                break;
        case M100_HALF:
                phy_ctrl |= PhyCtrlSpd100;
                break;
        case M100_FULL:
                phy_ctrl |= PhyCtrlDux | PhyCtrlSpd100;
                break;
        }

        iowrite32(phy_ctrl, port_base + PhyCtrl);
        mdelay(10);

        phy_ctrl &= ~PhyCtrlReset;
        iowrite32(phy_ctrl, port_base + PhyCtrl);
        mdelay(1);

        _sc92031_mii_write(port_base, MII_JAB,
                        PHY_16_JAB_ENB | PHY_16_PORT_ENB);
        _sc92031_mii_scan(port_base);

        netif_carrier_off(dev);
        netif_stop_queue(dev);
}

static void _sc92031_reset(struct net_device *dev)
{
        struct sc92031_priv *priv = netdev_priv(dev);
        void __iomem *port_base = priv->port_base;

        /* disable PM */
        iowrite32(0, port_base + PMConfig);

        /* soft reset the chip */
        iowrite32(Cfg0_Reset, port_base + Config0);
        mdelay(200);

        iowrite32(0, port_base + Config0);
        mdelay(10);

        /* disable interrupts */
        iowrite32(0, port_base + IntrMask);

        /* clear multicast address */
        iowrite32(0, port_base + MAR0);
        iowrite32(0, port_base + MAR0 + 4);

        /* init rx ring */
        iowrite32(priv->rx_ring_dma_addr, port_base + RxbufAddr);
        priv->rx_ring_tail = priv->rx_ring_dma_addr;

        /* init tx ring */
        _sc92031_tx_clear(dev);

        /* clear old register values */
        priv->intr_status = 0;
        atomic_set(&priv->intr_mask, 0);
        priv->rx_config = 0;
        priv->tx_config = 0;
        priv->mc_flags = 0;

        /* configure rx buffer size */
        /* NOTE: vendor driver had dead code here to enable early tx/rx */
        iowrite32(Cfg1_Rcv64K, port_base + Config1);

        _sc92031_phy_reset(dev);
        _sc92031_check_media(dev);

        /* calculate rx fifo overflow */
        priv->rx_value = 0;

        /* enable PM */
        iowrite32(priv->pm_config, port_base + PMConfig);

        /* clear intr register */
        ioread32(port_base + IntrStatus);
}

static void _sc92031_tx_tasklet(struct net_device *dev)
{
        struct sc92031_priv *priv = netdev_priv(dev);
        void __iomem *port_base = priv->port_base;

        unsigned old_tx_tail;
        unsigned entry;
        u32 tx_status;

        old_tx_tail = priv->tx_tail;
        while (priv->tx_head - priv->tx_tail > 0) {
                entry = priv->tx_tail % NUM_TX_DESC;
                tx_status = ioread32(port_base + TxStatus0 + entry * 4);

                if (!(tx_status & (TxStatOK | TxUnderrun | TxAborted)))
                        break;

                priv->tx_tail++;

                if (tx_status & TxStatOK) {
                        dev->stats.tx_bytes += tx_status & 0x1fff;
                        dev->stats.tx_packets++;
                        /* Note: TxCarrierLost is always asserted at 100mbps. */
                        dev->stats.collisions += (tx_status >> 22) & 0xf;
                }

                if (tx_status & (TxOutOfWindow | TxAborted)) {
                        dev->stats.tx_errors++;

                        if (tx_status & TxAborted)
                                dev->stats.tx_aborted_errors++;

                        if (tx_status & TxCarrierLost)
                                dev->stats.tx_carrier_errors++;

                        if (tx_status & TxOutOfWindow)
                                dev->stats.tx_window_errors++;
                }

                if (tx_status & TxUnderrun)
                        dev->stats.tx_fifo_errors++;
        }

        if (priv->tx_tail != old_tx_tail)
                if (netif_queue_stopped(dev))
                        netif_wake_queue(dev);
}

static void _sc92031_rx_tasklet_error(struct net_device *dev,
                                      u32 rx_status, unsigned rx_size)
{
        if(rx_size > (MAX_ETH_FRAME_SIZE + 4) || rx_size < 16) {
                dev->stats.rx_errors++;
                dev->stats.rx_length_errors++;
        }

        if (!(rx_status & RxStatesOK)) {
                dev->stats.rx_errors++;

                if (rx_status & (RxHugeFrame | RxSmallFrame))
                        dev->stats.rx_length_errors++;

                if (rx_status & RxBadAlign)
                        dev->stats.rx_frame_errors++;

                if (!(rx_status & RxCRCOK))
                        dev->stats.rx_crc_errors++;
        } else {
                struct sc92031_priv *priv = netdev_priv(dev);
                priv->rx_loss++;
        }
}

static void _sc92031_rx_tasklet(struct net_device *dev)
{
        struct sc92031_priv *priv = netdev_priv(dev);
        void __iomem *port_base = priv->port_base;

        dma_addr_t rx_ring_head;
        unsigned rx_len;
        unsigned rx_ring_offset;
        void *rx_ring = priv->rx_ring;

        rx_ring_head = ioread32(port_base + RxBufWPtr);
        rmb();

        /* rx_ring_head is only 17 bits in the RxBufWPtr register.
         * we need to change it to 32 bits physical address
         */
        rx_ring_head &= (dma_addr_t)(RX_BUF_LEN - 1);
        rx_ring_head |= priv->rx_ring_dma_addr & ~(dma_addr_t)(RX_BUF_LEN - 1);
        if (rx_ring_head < priv->rx_ring_dma_addr)
                rx_ring_head += RX_BUF_LEN;

        if (rx_ring_head >= priv->rx_ring_tail)
                rx_len = rx_ring_head - priv->rx_ring_tail;
        else
                rx_len = RX_BUF_LEN - (priv->rx_ring_tail - rx_ring_head);

        if (!rx_len)
                return;

        if (unlikely(rx_len > RX_BUF_LEN)) {
                if (printk_ratelimit())
                        printk(KERN_ERR "%s: rx packets length > rx buffer\n",
                                        dev->name);
                return;
        }

        rx_ring_offset = (priv->rx_ring_tail - priv->rx_ring_dma_addr) % RX_BUF_LEN;

        while (rx_len) {
                u32 rx_status;
                unsigned rx_size, rx_size_align, pkt_size;
                struct sk_buff *skb;

                rx_status = le32_to_cpup((__le32 *)(rx_ring + rx_ring_offset));
                rmb();

                rx_size = rx_status >> 20;
                rx_size_align = (rx_size + 3) & ~3;     // for 4 bytes aligned
                pkt_size = rx_size - 4; // Omit the four octet CRC from the length.

                rx_ring_offset = (rx_ring_offset + 4) % RX_BUF_LEN;

                if (unlikely(rx_status == 0
                                || rx_size > (MAX_ETH_FRAME_SIZE + 4)
                                || rx_size < 16
                                || !(rx_status & RxStatesOK))) {
                        _sc92031_rx_tasklet_error(dev, rx_status, rx_size);
                        break;
                }

                if (unlikely(rx_size_align + 4 > rx_len)) {
                        if (printk_ratelimit())
                                printk(KERN_ERR "%s: rx_len is too small\n", dev->name);
                        break;
                }

                rx_len -= rx_size_align + 4;

                skb = netdev_alloc_skb(dev, pkt_size + NET_IP_ALIGN);
                if (unlikely(!skb)) {
                        if (printk_ratelimit())
                                printk(KERN_ERR "%s: Couldn't allocate a skb_buff for a packet of size %u\n",
                                                dev->name, pkt_size);
                        goto next;
                }

                skb_reserve(skb, NET_IP_ALIGN);

                if ((rx_ring_offset + pkt_size) > RX_BUF_LEN) {
                        memcpy(skb_put(skb, RX_BUF_LEN - rx_ring_offset),
                                rx_ring + rx_ring_offset, RX_BUF_LEN - rx_ring_offset);
                        memcpy(skb_put(skb, pkt_size - (RX_BUF_LEN - rx_ring_offset)),
                                rx_ring, pkt_size - (RX_BUF_LEN - rx_ring_offset));
                } else {
                        memcpy(skb_put(skb, pkt_size), rx_ring + rx_ring_offset, pkt_size);
                }

                skb->protocol = eth_type_trans(skb, dev);
                netif_rx(skb);

                dev->stats.rx_bytes += pkt_size;
                dev->stats.rx_packets++;

                if (rx_status & Rx_Multicast)
                        dev->stats.multicast++;

        next:
                rx_ring_offset = (rx_ring_offset + rx_size_align) % RX_BUF_LEN;
        }
        mb();

        priv->rx_ring_tail = rx_ring_head;
        iowrite32(priv->rx_ring_tail, port_base + RxBufRPtr);
}

static void _sc92031_link_tasklet(struct net_device *dev)
{
        if (_sc92031_check_media(dev))
                netif_wake_queue(dev);
        else {
                netif_stop_queue(dev);
                dev->stats.tx_carrier_errors++;
        }
}

static void sc92031_tasklet(unsigned long data)
{
        struct net_device *dev = (struct net_device *)data;
        struct sc92031_priv *priv = netdev_priv(dev);
        void __iomem *port_base = priv->port_base;
        u32 intr_status, intr_mask;

        intr_status = priv->intr_status;

        spin_lock(&priv->lock);

        if (unlikely(!netif_running(dev)))
                goto out;

        if (intr_status & TxOK)
                _sc92031_tx_tasklet(dev);

        if (intr_status & RxOK)
                _sc92031_rx_tasklet(dev);

        if (intr_status & RxOverflow)
                dev->stats.rx_errors++;

        if (intr_status & TimeOut) {
                dev->stats.rx_errors++;
                dev->stats.rx_length_errors++;
        }

        if (intr_status & (LinkFail | LinkOK))
                _sc92031_link_tasklet(dev);

out:
        intr_mask = atomic_read(&priv->intr_mask);
        rmb();

        iowrite32(intr_mask, port_base + IntrMask);
        mmiowb();

        spin_unlock(&priv->lock);
}

static irqreturn_t sc92031_interrupt(int irq, void *dev_id)
{
        struct net_device *dev = dev_id;
        struct sc92031_priv *priv = netdev_priv(dev);
        void __iomem *port_base = priv->port_base;
        u32 intr_status, intr_mask;

        /* mask interrupts before clearing IntrStatus */
        iowrite32(0, port_base + IntrMask);
        _sc92031_dummy_read(port_base);

        intr_status = ioread32(port_base + IntrStatus);
        if (unlikely(intr_status == 0xffffffff))
                return IRQ_NONE;        // hardware has gone missing

        intr_status &= IntrBits;
        if (!intr_status)
                goto out_none;

        priv->intr_status = intr_status;
        tasklet_schedule(&priv->tasklet);

        return IRQ_HANDLED;

out_none:
        intr_mask = atomic_read(&priv->intr_mask);
        rmb();

        iowrite32(intr_mask, port_base + IntrMask);
        mmiowb();

        return IRQ_NONE;
}

static struct net_device_stats *sc92031_get_stats(struct net_device *dev)
{
        struct sc92031_priv *priv = netdev_priv(dev);
        void __iomem *port_base = priv->port_base;

        // FIXME I do not understand what is this trying to do.
        if (netif_running(dev)) {
                int temp;

                spin_lock_bh(&priv->lock);

                /* Update the error count. */
                temp = (ioread32(port_base + RxStatus0) >> 16) & 0xffff;

                if (temp == 0xffff) {
                        priv->rx_value += temp;
                        dev->stats.rx_fifo_errors = priv->rx_value;
                } else
                        dev->stats.rx_fifo_errors = temp + priv->rx_value;

                spin_unlock_bh(&priv->lock);
        }

        return &dev->stats;
}

static netdev_tx_t sc92031_start_xmit(struct sk_buff *skb,
                                      struct net_device *dev)
{
        struct sc92031_priv *priv = netdev_priv(dev);
        void __iomem *port_base = priv->port_base;
        unsigned len;
        unsigned entry;
        u32 tx_status;

        if (unlikely(skb->len > TX_BUF_SIZE)) {
                dev->stats.tx_dropped++;
                goto out;
        }

        spin_lock(&priv->lock);

        if (unlikely(!netif_carrier_ok(dev))) {
                dev->stats.tx_dropped++;
                goto out_unlock;
        }

        BUG_ON(priv->tx_head - priv->tx_tail >= NUM_TX_DESC);

        entry = priv->tx_head++ % NUM_TX_DESC;

        skb_copy_and_csum_dev(skb, priv->tx_bufs + entry * TX_BUF_SIZE);

        len = skb->len;
        if (len < ETH_ZLEN) {
                memset(priv->tx_bufs + entry * TX_BUF_SIZE + len,
                                0, ETH_ZLEN - len);
                len = ETH_ZLEN;
        }

        wmb();

        if (len < 100)
                tx_status = len;
        else if (len < 300)
                tx_status = 0x30000 | len;
        else
                tx_status = 0x50000 | len;

        iowrite32(priv->tx_bufs_dma_addr + entry * TX_BUF_SIZE,
                        port_base + TxAddr0 + entry * 4);
        iowrite32(tx_status, port_base + TxStatus0 + entry * 4);
        mmiowb();

        dev->trans_start = jiffies;

        if (priv->tx_head - priv->tx_tail >= NUM_TX_DESC)
                netif_stop_queue(dev);

out_unlock:
        spin_unlock(&priv->lock);

out:

        dev_kfree_skb(skb);

        return NETDEV_TX_OK;
}

static int sc92031_open(struct net_device *dev)
{
        int err;
        struct sc92031_priv *priv = netdev_priv(dev);
        struct pci_dev *pdev = priv->pdev;

        priv->rx_ring = pci_alloc_consistent(pdev, RX_BUF_LEN,
                        &priv->rx_ring_dma_addr);
        if (unlikely(!priv->rx_ring)) {
                err = -ENOMEM;
                goto out_alloc_rx_ring;
        }

        priv->tx_bufs = pci_alloc_consistent(pdev, TX_BUF_TOT_LEN,
                        &priv->tx_bufs_dma_addr);
        if (unlikely(!priv->tx_bufs)) {
                err = -ENOMEM;
                goto out_alloc_tx_bufs;
        }
        priv->tx_head = priv->tx_tail = 0;

        err = request_irq(pdev->irq, sc92031_interrupt,
                        IRQF_SHARED, dev->name, dev);
        if (unlikely(err < 0))
                goto out_request_irq;

        priv->pm_config = 0;

        /* Interrupts already disabled by sc92031_stop or sc92031_probe */
        spin_lock_bh(&priv->lock);

        _sc92031_reset(dev);
        mmiowb();

        spin_unlock_bh(&priv->lock);
        sc92031_enable_interrupts(dev);

        if (netif_carrier_ok(dev))
                netif_start_queue(dev);
        else
                netif_tx_disable(dev);

        return 0;

out_request_irq:
        pci_free_consistent(pdev, TX_BUF_TOT_LEN, priv->tx_bufs,
                        priv->tx_bufs_dma_addr);
out_alloc_tx_bufs:
        pci_free_consistent(pdev, RX_BUF_LEN, priv->rx_ring,
                        priv->rx_ring_dma_addr);
out_alloc_rx_ring:
        return err;
}

static int sc92031_stop(struct net_device *dev)
{
        struct sc92031_priv *priv = netdev_priv(dev);
        struct pci_dev *pdev = priv->pdev;

        netif_tx_disable(dev);

        /* Disable interrupts, stop Tx and Rx. */
        sc92031_disable_interrupts(dev);

        spin_lock_bh(&priv->lock);

        _sc92031_disable_tx_rx(dev);
        _sc92031_tx_clear(dev);
        mmiowb();

        spin_unlock_bh(&priv->lock);

        free_irq(pdev->irq, dev);
        pci_free_consistent(pdev, TX_BUF_TOT_LEN, priv->tx_bufs,
                        priv->tx_bufs_dma_addr);
        pci_free_consistent(pdev, RX_BUF_LEN, priv->rx_ring,
                        priv->rx_ring_dma_addr);

        return 0;
}

static void sc92031_set_multicast_list(struct net_device *dev)
{
        struct sc92031_priv *priv = netdev_priv(dev);

        spin_lock_bh(&priv->lock);

        _sc92031_set_mar(dev);
        _sc92031_set_rx_config(dev);
        mmiowb();

        spin_unlock_bh(&priv->lock);
}

static void sc92031_tx_timeout(struct net_device *dev)
{
        struct sc92031_priv *priv = netdev_priv(dev);

        /* Disable interrupts by clearing the interrupt mask.*/
        sc92031_disable_interrupts(dev);

        spin_lock(&priv->lock);

        priv->tx_timeouts++;

        _sc92031_reset(dev);
        mmiowb();

        spin_unlock(&priv->lock);

        /* enable interrupts */
        sc92031_enable_interrupts(dev);

        if (netif_carrier_ok(dev))
                netif_wake_queue(dev);
}

#ifdef CONFIG_NET_POLL_CONTROLLER
static void sc92031_poll_controller(struct net_device *dev)
{
        disable_irq(dev->irq);
        if (sc92031_interrupt(dev->irq, dev) != IRQ_NONE)
                sc92031_tasklet((unsigned long)dev);
        enable_irq(dev->irq);
}
#endif

static int sc92031_ethtool_get_settings(struct net_device *dev,
                struct ethtool_cmd *cmd)
{
        struct sc92031_priv *priv = netdev_priv(dev);
        void __iomem *port_base = priv->port_base;
        u8 phy_address;
        u32 phy_ctrl;
        u16 output_status;

        spin_lock_bh(&priv->lock);

        phy_address = ioread32(port_base + Miicmd1) >> 27;
        phy_ctrl = ioread32(port_base + PhyCtrl);

        output_status = _sc92031_mii_read(port_base, MII_OutputStatus);
        _sc92031_mii_scan(port_base);
        mmiowb();

        spin_unlock_bh(&priv->lock);

        cmd->supported = SUPPORTED_10baseT_Half | SUPPORTED_10baseT_Full
                        | SUPPORTED_100baseT_Half | SUPPORTED_100baseT_Full
                        | SUPPORTED_Autoneg | SUPPORTED_TP | SUPPORTED_MII;

        cmd->advertising = ADVERTISED_TP | ADVERTISED_MII;

        if ((phy_ctrl & (PhyCtrlDux | PhyCtrlSpd100 | PhyCtrlSpd10))
                        == (PhyCtrlDux | PhyCtrlSpd100 | PhyCtrlSpd10))
                cmd->advertising |= ADVERTISED_Autoneg;

        if ((phy_ctrl & PhyCtrlSpd10) == PhyCtrlSpd10)
                cmd->advertising |= ADVERTISED_10baseT_Half;

        if ((phy_ctrl & (PhyCtrlSpd10 | PhyCtrlDux))
                        == (PhyCtrlSpd10 | PhyCtrlDux))
                cmd->advertising |= ADVERTISED_10baseT_Full;

        if ((phy_ctrl & PhyCtrlSpd100) == PhyCtrlSpd100)
                cmd->advertising |= ADVERTISED_100baseT_Half;

        if ((phy_ctrl & (PhyCtrlSpd100 | PhyCtrlDux))
                        == (PhyCtrlSpd100 | PhyCtrlDux))
                cmd->advertising |= ADVERTISED_100baseT_Full;

        if (phy_ctrl & PhyCtrlAne)
                cmd->advertising |= ADVERTISED_Autoneg;

        cmd->speed = (output_status & 0x2) ? SPEED_100 : SPEED_10;
        cmd->duplex = (output_status & 0x4) ? DUPLEX_FULL : DUPLEX_HALF;
        cmd->port = PORT_MII;
        cmd->phy_address = phy_address;
        cmd->transceiver = XCVR_INTERNAL;
        cmd->autoneg = (phy_ctrl & PhyCtrlAne) ? AUTONEG_ENABLE : AUTONEG_DISABLE;

        return 0;
}

static int sc92031_ethtool_set_settings(struct net_device *dev,
                struct ethtool_cmd *cmd)
{
        struct sc92031_priv *priv = netdev_priv(dev);
        void __iomem *port_base = priv->port_base;
        u32 phy_ctrl;
        u32 old_phy_ctrl;

        if (!(cmd->speed == SPEED_10 || cmd->speed == SPEED_100))
                return -EINVAL;
        if (!(cmd->duplex == DUPLEX_HALF || cmd->duplex == DUPLEX_FULL))
                return -EINVAL;
        if (!(cmd->port == PORT_MII))
                return -EINVAL;
        if (!(cmd->phy_address == 0x1f))
                return -EINVAL;
        if (!(cmd->transceiver == XCVR_INTERNAL))
                return -EINVAL;
        if (!(cmd->autoneg == AUTONEG_DISABLE || cmd->autoneg == AUTONEG_ENABLE))
                return -EINVAL;

        if (cmd->autoneg == AUTONEG_ENABLE) {
                if (!(cmd->advertising & (ADVERTISED_Autoneg
                                | ADVERTISED_100baseT_Full
                                | ADVERTISED_100baseT_Half
                                | ADVERTISED_10baseT_Full
                                | ADVERTISED_10baseT_Half)))
                        return -EINVAL;

                phy_ctrl = PhyCtrlAne;

                // FIXME: I'm not sure what the original code was trying to do
                if (cmd->advertising & ADVERTISED_Autoneg)
                        phy_ctrl |= PhyCtrlDux | PhyCtrlSpd100 | PhyCtrlSpd10;
                if (cmd->advertising & ADVERTISED_100baseT_Full)
                        phy_ctrl |= PhyCtrlDux | PhyCtrlSpd100;
                if (cmd->advertising & ADVERTISED_100baseT_Half)
                        phy_ctrl |= PhyCtrlSpd100;
                if (cmd->advertising & ADVERTISED_10baseT_Full)
                        phy_ctrl |= PhyCtrlSpd10 | PhyCtrlDux;
                if (cmd->advertising & ADVERTISED_10baseT_Half)
                        phy_ctrl |= PhyCtrlSpd10;
        } else {
                // FIXME: Whole branch guessed
                phy_ctrl = 0;

                if (cmd->speed == SPEED_10)
                        phy_ctrl |= PhyCtrlSpd10;
                else /* cmd->speed == SPEED_100 */
                        phy_ctrl |= PhyCtrlSpd100;

                if (cmd->duplex == DUPLEX_FULL)
                        phy_ctrl |= PhyCtrlDux;
        }

        spin_lock_bh(&priv->lock);

        old_phy_ctrl = ioread32(port_base + PhyCtrl);
        phy_ctrl |= old_phy_ctrl & ~(PhyCtrlAne | PhyCtrlDux
                        | PhyCtrlSpd100 | PhyCtrlSpd10);
        if (phy_ctrl != old_phy_ctrl)
                iowrite32(phy_ctrl, port_base + PhyCtrl);

        spin_unlock_bh(&priv->lock);

        return 0;
}

static void sc92031_ethtool_get_drvinfo(struct net_device *dev,
                struct ethtool_drvinfo *drvinfo)
{
        struct sc92031_priv *priv = netdev_priv(dev);
        struct pci_dev *pdev = priv->pdev;

        strcpy(drvinfo->driver, SC92031_NAME);
        strcpy(drvinfo->bus_info, pci_name(pdev));
}

static void sc92031_ethtool_get_wol(struct net_device *dev,
                struct ethtool_wolinfo *wolinfo)
{
        struct sc92031_priv *priv = netdev_priv(dev);
        void __iomem *port_base = priv->port_base;
        u32 pm_config;

        spin_lock_bh(&priv->lock);
        pm_config = ioread32(port_base + PMConfig);
        spin_unlock_bh(&priv->lock);

        // FIXME: Guessed
        wolinfo->supported = WAKE_PHY | WAKE_MAGIC
                        | WAKE_UCAST | WAKE_MCAST | WAKE_BCAST;
        wolinfo->wolopts = 0;

        if (pm_config & PM_LinkUp)
                wolinfo->wolopts |= WAKE_PHY;

        if (pm_config & PM_Magic)
                wolinfo->wolopts |= WAKE_MAGIC;

        if (pm_config & PM_WakeUp)
                // FIXME: Guessed
                wolinfo->wolopts |= WAKE_UCAST | WAKE_MCAST | WAKE_BCAST;
}

static int sc92031_ethtool_set_wol(struct net_device *dev,
                struct ethtool_wolinfo *wolinfo)
{
        struct sc92031_priv *priv = netdev_priv(dev);
        void __iomem *port_base = priv->port_base;
        u32 pm_config;

        spin_lock_bh(&priv->lock);

        pm_config = ioread32(port_base + PMConfig)
                        & ~(PM_LinkUp | PM_Magic | PM_WakeUp);

        if (wolinfo->wolopts & WAKE_PHY)
                pm_config |= PM_LinkUp;

        if (wolinfo->wolopts & WAKE_MAGIC)
                pm_config |= PM_Magic;

        // FIXME: Guessed
        if (wolinfo->wolopts & (WAKE_UCAST | WAKE_MCAST | WAKE_BCAST))
                pm_config |= PM_WakeUp;

        priv->pm_config = pm_config;
        iowrite32(pm_config, port_base + PMConfig);
        mmiowb();

        spin_unlock_bh(&priv->lock);

        return 0;
}

static int sc92031_ethtool_nway_reset(struct net_device *dev)
{
        int err = 0;
        struct sc92031_priv *priv = netdev_priv(dev);
        void __iomem *port_base = priv->port_base;
        u16 bmcr;

        spin_lock_bh(&priv->lock);

        bmcr = _sc92031_mii_read(port_base, MII_BMCR);
        if (!(bmcr & BMCR_ANENABLE)) {
                err = -EINVAL;
                goto out;
        }

        _sc92031_mii_write(port_base, MII_BMCR, bmcr | BMCR_ANRESTART);

out:
        _sc92031_mii_scan(port_base);
        mmiowb();

        spin_unlock_bh(&priv->lock);

        return err;
}

static const char sc92031_ethtool_stats_strings[SILAN_STATS_NUM][ETH_GSTRING_LEN] = {
        "tx_timeout",
        "rx_loss",
};

static void sc92031_ethtool_get_strings(struct net_device *dev,
                u32 stringset, u8 *data)
{
        if (stringset == ETH_SS_STATS)
                memcpy(data, sc92031_ethtool_stats_strings,
                                SILAN_STATS_NUM * ETH_GSTRING_LEN);
}

static int sc92031_ethtool_get_sset_count(struct net_device *dev, int sset)
{
        switch (sset) {
        case ETH_SS_STATS:
                return SILAN_STATS_NUM;
        default:
                return -EOPNOTSUPP;
        }
}

static void sc92031_ethtool_get_ethtool_stats(struct net_device *dev,
                struct ethtool_stats *stats, u64 *data)
{
        struct sc92031_priv *priv = netdev_priv(dev);

        spin_lock_bh(&priv->lock);
        data[0] = priv->tx_timeouts;
        data[1] = priv->rx_loss;
        spin_unlock_bh(&priv->lock);
}

static const struct ethtool_ops sc92031_ethtool_ops = {
        .get_settings           = sc92031_ethtool_get_settings,
        .set_settings           = sc92031_ethtool_set_settings,
        .get_drvinfo            = sc92031_ethtool_get_drvinfo,
        .get_wol                = sc92031_ethtool_get_wol,
        .set_wol                = sc92031_ethtool_set_wol,
        .nway_reset             = sc92031_ethtool_nway_reset,
        .get_link               = ethtool_op_get_link,
        .get_strings            = sc92031_ethtool_get_strings,
        .get_sset_count         = sc92031_ethtool_get_sset_count,
        .get_ethtool_stats      = sc92031_ethtool_get_ethtool_stats,
};


static const struct net_device_ops sc92031_netdev_ops = {
        .ndo_get_stats          = sc92031_get_stats,
        .ndo_start_xmit         = sc92031_start_xmit,
        .ndo_open               = sc92031_open,
        .ndo_stop               = sc92031_stop,
        .ndo_set_multicast_list = sc92031_set_multicast_list,
        .ndo_change_mtu         = eth_change_mtu,
        .ndo_validate_addr      = eth_validate_addr,
        .ndo_set_mac_address    = eth_mac_addr,
        .ndo_tx_timeout         = sc92031_tx_timeout,
#ifdef CONFIG_NET_POLL_CONTROLLER
        .ndo_poll_controller    = sc92031_poll_controller,
#endif
};

static int __devinit sc92031_probe(struct pci_dev *pdev,
                const struct pci_device_id *id)
{
        int err;
        void __iomem* port_base;
        struct net_device *dev;
        struct sc92031_priv *priv;
        u32 mac0, mac1;
        unsigned long base_addr;

        err = pci_enable_device(pdev);
        if (unlikely(err < 0))
                goto out_enable_device;

        pci_set_master(pdev);

        err = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
        if (unlikely(err < 0))
                goto out_set_dma_mask;

        err = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(32));
        if (unlikely(err < 0))
                goto out_set_dma_mask;

        err = pci_request_regions(pdev, SC92031_NAME);
        if (unlikely(err < 0))
                goto out_request_regions;

        port_base = pci_iomap(pdev, SC92031_USE_BAR, 0);
        if (unlikely(!port_base)) {
                err = -EIO;
                goto out_iomap;
        }

        dev = alloc_etherdev(sizeof(struct sc92031_priv));
        if (unlikely(!dev)) {
                err = -ENOMEM;
                goto out_alloc_etherdev;
        }

        pci_set_drvdata(pdev, dev);
        SET_NETDEV_DEV(dev, &pdev->dev);

#if SC92031_USE_BAR == 0
        dev->mem_start = pci_resource_start(pdev, SC92031_USE_BAR);
        dev->mem_end = pci_resource_end(pdev, SC92031_USE_BAR);
#elif SC92031_USE_BAR == 1
        dev->base_addr = pci_resource_start(pdev, SC92031_USE_BAR);
#endif
        dev->irq = pdev->irq;

        /* faked with skb_copy_and_csum_dev */
        dev->features = NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_HIGHDMA;

        dev->netdev_ops         = &sc92031_netdev_ops;
        dev->watchdog_timeo     = TX_TIMEOUT;
        dev->ethtool_ops        = &sc92031_ethtool_ops;

        priv = netdev_priv(dev);
        spin_lock_init(&priv->lock);
        priv->port_base = port_base;
        priv->pdev = pdev;
        tasklet_init(&priv->tasklet, sc92031_tasklet, (unsigned long)dev);
        /* Fudge tasklet count so the call to sc92031_enable_interrupts at
         * sc92031_open will work correctly */
        tasklet_disable_nosync(&priv->tasklet);

        /* PCI PM Wakeup */
        iowrite32((~PM_LongWF & ~PM_LWPTN) | PM_Enable, port_base + PMConfig);

        mac0 = ioread32(port_base + MAC0);
        mac1 = ioread32(port_base + MAC0 + 4);
        dev->dev_addr[0] = dev->perm_addr[0] = mac0 >> 24;
        dev->dev_addr[1] = dev->perm_addr[1] = mac0 >> 16;
        dev->dev_addr[2] = dev->perm_addr[2] = mac0 >> 8;
        dev->dev_addr[3] = dev->perm_addr[3] = mac0;
        dev->dev_addr[4] = dev->perm_addr[4] = mac1 >> 8;
        dev->dev_addr[5] = dev->perm_addr[5] = mac1;

        err = register_netdev(dev);
        if (err < 0)
                goto out_register_netdev;

#if SC92031_USE_BAR == 0
        base_addr = dev->mem_start;
#elif SC92031_USE_BAR == 1
        base_addr = dev->base_addr;
#endif
        printk(KERN_INFO "%s: SC92031 at 0x%lx, %pM, IRQ %d\n", dev->name,
                        base_addr, dev->dev_addr, dev->irq);

        return 0;

out_register_netdev:
        free_netdev(dev);
out_alloc_etherdev:
        pci_iounmap(pdev, port_base);
out_iomap:
        pci_release_regions(pdev);
out_request_regions:
out_set_dma_mask:
        pci_disable_device(pdev);
out_enable_device:
        return err;
}

static void __devexit sc92031_remove(struct pci_dev *pdev)
{
        struct net_device *dev = pci_get_drvdata(pdev);
        struct sc92031_priv *priv = netdev_priv(dev);
        void __iomem* port_base = priv->port_base;

        unregister_netdev(dev);
        free_netdev(dev);
        pci_iounmap(pdev, port_base);
        pci_release_regions(pdev);
        pci_disable_device(pdev);
}

static int sc92031_suspend(struct pci_dev *pdev, pm_message_t state)
{
        struct net_device *dev = pci_get_drvdata(pdev);
        struct sc92031_priv *priv = netdev_priv(dev);

        pci_save_state(pdev);

        if (!netif_running(dev))
                goto out;

        netif_device_detach(dev);

        /* Disable interrupts, stop Tx and Rx. */
        sc92031_disable_interrupts(dev);

        spin_lock_bh(&priv->lock);

        _sc92031_disable_tx_rx(dev);
        _sc92031_tx_clear(dev);
        mmiowb();

        spin_unlock_bh(&priv->lock);

out:
        pci_set_power_state(pdev, pci_choose_state(pdev, state));

        return 0;
}

static int sc92031_resume(struct pci_dev *pdev)
{
        struct net_device *dev = pci_get_drvdata(pdev);
        struct sc92031_priv *priv = netdev_priv(dev);

        pci_restore_state(pdev);
        pci_set_power_state(pdev, PCI_D0);

        if (!netif_running(dev))
                goto out;

        /* Interrupts already disabled by sc92031_suspend */
        spin_lock_bh(&priv->lock);

        _sc92031_reset(dev);
        mmiowb();

        spin_unlock_bh(&priv->lock);
        sc92031_enable_interrupts(dev);

        netif_device_attach(dev);

        if (netif_carrier_ok(dev))
                netif_wake_queue(dev);
        else
                netif_tx_disable(dev);

out:
        return 0;
}

static struct pci_device_id sc92031_pci_device_id_table[] __devinitdata = {
        { PCI_DEVICE(PCI_VENDOR_ID_SILAN, 0x2031) },
        { PCI_DEVICE(PCI_VENDOR_ID_SILAN, 0x8139) },
        { PCI_DEVICE(0x1088, 0x2031) },
        { 0, }
};
MODULE_DEVICE_TABLE(pci, sc92031_pci_device_id_table);

static struct pci_driver sc92031_pci_driver = {
        .name           = SC92031_NAME,
        .id_table       = sc92031_pci_device_id_table,
        .probe          = sc92031_probe,
        .remove         = __devexit_p(sc92031_remove),
        .suspend        = sc92031_suspend,
        .resume         = sc92031_resume,
};

static int __init sc92031_init(void)
{
        return pci_register_driver(&sc92031_pci_driver);
}

static void __exit sc92031_exit(void)
{
        pci_unregister_driver(&sc92031_pci_driver);
}

module_init(sc92031_init);
module_exit(sc92031_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Cesar Eduardo Barros <cesarb@cesarb.net>");
MODULE_DESCRIPTION("Silan SC92031 PCI Fast Ethernet Adapter driver");