root/drivers/net/ethernet/atheros/atl1c/atl1c_main.c
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright(c) 2008 - 2009 Atheros Corporation. All rights reserved.
 *
 * Derived from Intel e1000 driver
 * Copyright(c) 1999 - 2005 Intel Corporation. All rights reserved.
 */

#include "atl1c.h"

char atl1c_driver_name[] = "atl1c";

/*
 * atl1c_pci_tbl - PCI Device ID Table
 *
 * Wildcard entries (PCI_ANY_ID) should come last
 * Last entry must be all 0s
 *
 * { Vendor ID, Device ID, SubVendor ID, SubDevice ID,
 *   Class, Class Mask, private data (not used) }
 */
static const struct pci_device_id atl1c_pci_tbl[] = {
        {PCI_DEVICE(PCI_VENDOR_ID_ATTANSIC, PCI_DEVICE_ID_ATTANSIC_L1C)},
        {PCI_DEVICE(PCI_VENDOR_ID_ATTANSIC, PCI_DEVICE_ID_ATTANSIC_L2C)},
        {PCI_DEVICE(PCI_VENDOR_ID_ATTANSIC, PCI_DEVICE_ID_ATHEROS_L2C_B)},
        {PCI_DEVICE(PCI_VENDOR_ID_ATTANSIC, PCI_DEVICE_ID_ATHEROS_L2C_B2)},
        {PCI_DEVICE(PCI_VENDOR_ID_ATTANSIC, PCI_DEVICE_ID_ATHEROS_L1D)},
        {PCI_DEVICE(PCI_VENDOR_ID_ATTANSIC, PCI_DEVICE_ID_ATHEROS_L1D_2_0)},
        /* required last entry */
        { 0 }
};
MODULE_DEVICE_TABLE(pci, atl1c_pci_tbl);

MODULE_AUTHOR("Jie Yang");
MODULE_AUTHOR("Qualcomm Atheros Inc.");
MODULE_DESCRIPTION("Qualcomm Atheros 100/1000M Ethernet Network Driver");
MODULE_LICENSE("GPL");

struct atl1c_qregs {
        u16 tpd_addr_lo;
        u16 tpd_prod;
        u16 tpd_cons;
        u16 rfd_addr_lo;
        u16 rrd_addr_lo;
        u16 rfd_prod;
        u32 tx_isr;
        u32 rx_isr;
};

static struct atl1c_qregs atl1c_qregs[AT_MAX_TRANSMIT_QUEUE] = {
        {
                REG_TPD_PRI0_ADDR_LO, REG_TPD_PRI0_PIDX, REG_TPD_PRI0_CIDX,
                REG_RFD0_HEAD_ADDR_LO, REG_RRD0_HEAD_ADDR_LO,
                REG_MB_RFD0_PROD_IDX, ISR_TX_PKT_0, ISR_RX_PKT_0
        },
        {
                REG_TPD_PRI1_ADDR_LO, REG_TPD_PRI1_PIDX, REG_TPD_PRI1_CIDX,
                REG_RFD1_HEAD_ADDR_LO, REG_RRD1_HEAD_ADDR_LO,
                REG_MB_RFD1_PROD_IDX, ISR_TX_PKT_1, ISR_RX_PKT_1
        },
        {
                REG_TPD_PRI2_ADDR_LO, REG_TPD_PRI2_PIDX, REG_TPD_PRI2_CIDX,
                REG_RFD2_HEAD_ADDR_LO, REG_RRD2_HEAD_ADDR_LO,
                REG_MB_RFD2_PROD_IDX, ISR_TX_PKT_2, ISR_RX_PKT_2
        },
        {
                REG_TPD_PRI3_ADDR_LO, REG_TPD_PRI3_PIDX, REG_TPD_PRI3_CIDX,
                REG_RFD3_HEAD_ADDR_LO, REG_RRD3_HEAD_ADDR_LO,
                REG_MB_RFD3_PROD_IDX, ISR_TX_PKT_3, ISR_RX_PKT_3
        },
};

static int atl1c_stop_mac(struct atl1c_hw *hw);
static void atl1c_disable_l0s_l1(struct atl1c_hw *hw);
static void atl1c_set_aspm(struct atl1c_hw *hw, u16 link_speed);
static void atl1c_start_mac(struct atl1c_adapter *adapter);
static int atl1c_up(struct atl1c_adapter *adapter);
static void atl1c_down(struct atl1c_adapter *adapter);
static int atl1c_reset_mac(struct atl1c_hw *hw);
static void atl1c_reset_dma_ring(struct atl1c_adapter *adapter);
static int atl1c_configure(struct atl1c_adapter *adapter);
static int atl1c_alloc_rx_buffer(struct atl1c_adapter *adapter, u32 queue,
                                 bool napi_mode);


static const u32 atl1c_default_msg = NETIF_MSG_DRV | NETIF_MSG_PROBE |
        NETIF_MSG_LINK | NETIF_MSG_TIMER | NETIF_MSG_IFDOWN | NETIF_MSG_IFUP;
static void atl1c_pcie_patch(struct atl1c_hw *hw)
{
        u32 mst_data, data;

        /* pclk sel could switch to 25M */
        AT_READ_REG(hw, REG_MASTER_CTRL, &mst_data);
        mst_data &= ~MASTER_CTRL_CLK_SEL_DIS;
        AT_WRITE_REG(hw, REG_MASTER_CTRL, mst_data);

        /* WoL/PCIE related settings */
        if (hw->nic_type == athr_l1c || hw->nic_type == athr_l2c) {
                AT_READ_REG(hw, REG_PCIE_PHYMISC, &data);
                data |= PCIE_PHYMISC_FORCE_RCV_DET;
                AT_WRITE_REG(hw, REG_PCIE_PHYMISC, data);
        } else { /* new dev set bit5 of MASTER */
                if (!(mst_data & MASTER_CTRL_WAKEN_25M))
                        AT_WRITE_REG(hw, REG_MASTER_CTRL,
                                mst_data | MASTER_CTRL_WAKEN_25M);
        }
        /* aspm/PCIE setting only for l2cb 1.0 */
        if (hw->nic_type == athr_l2c_b && hw->revision_id == L2CB_V10) {
                AT_READ_REG(hw, REG_PCIE_PHYMISC2, &data);
                data = FIELD_SETX(data, PCIE_PHYMISC2_CDR_BW,
                        L2CB1_PCIE_PHYMISC2_CDR_BW);
                data = FIELD_SETX(data, PCIE_PHYMISC2_L0S_TH,
                        L2CB1_PCIE_PHYMISC2_L0S_TH);
                AT_WRITE_REG(hw, REG_PCIE_PHYMISC2, data);
                /* extend L1 sync timer */
                AT_READ_REG(hw, REG_LINK_CTRL, &data);
                data |= LINK_CTRL_EXT_SYNC;
                AT_WRITE_REG(hw, REG_LINK_CTRL, data);
        }
        /* l2cb 1.x & l1d 1.x */
        if (hw->nic_type == athr_l2c_b || hw->nic_type == athr_l1d) {
                AT_READ_REG(hw, REG_PM_CTRL, &data);
                data |= PM_CTRL_L0S_BUFSRX_EN;
                AT_WRITE_REG(hw, REG_PM_CTRL, data);
                /* clear vendor msg */
                AT_READ_REG(hw, REG_DMA_DBG, &data);
                AT_WRITE_REG(hw, REG_DMA_DBG, data & ~DMA_DBG_VENDOR_MSG);
        }
}

/* FIXME: no need any more ? */
/*
 * atl1c_init_pcie - init PCIE module
 */
static void atl1c_reset_pcie(struct atl1c_hw *hw, u32 flag)
{
        u32 data;
        u32 pci_cmd;
        struct pci_dev *pdev = hw->adapter->pdev;
        int pos;

        AT_READ_REG(hw, PCI_COMMAND, &pci_cmd);
        pci_cmd &= ~PCI_COMMAND_INTX_DISABLE;
        pci_cmd |= (PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER |
                PCI_COMMAND_IO);
        AT_WRITE_REG(hw, PCI_COMMAND, pci_cmd);

        /*
         * Clear any PowerSaveing Settings
         */
        pci_enable_wake(pdev, PCI_D3hot, 0);
        pci_enable_wake(pdev, PCI_D3cold, 0);
        /* wol sts read-clear */
        AT_READ_REG(hw, REG_WOL_CTRL, &data);
        AT_WRITE_REG(hw, REG_WOL_CTRL, 0);

        /*
         * Mask some pcie error bits
         */
        pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_ERR);
        if (pos) {
                pci_read_config_dword(pdev, pos + PCI_ERR_UNCOR_SEVER, &data);
                data &= ~(PCI_ERR_UNC_DLP | PCI_ERR_UNC_FCP);
                pci_write_config_dword(pdev, pos + PCI_ERR_UNCOR_SEVER, data);
        }
        /* clear error status */
        pcie_capability_write_word(pdev, PCI_EXP_DEVSTA,
                        PCI_EXP_DEVSTA_NFED |
                        PCI_EXP_DEVSTA_FED |
                        PCI_EXP_DEVSTA_CED |
                        PCI_EXP_DEVSTA_URD);

        AT_READ_REG(hw, REG_LTSSM_ID_CTRL, &data);
        data &= ~LTSSM_ID_EN_WRO;
        AT_WRITE_REG(hw, REG_LTSSM_ID_CTRL, data);

        atl1c_pcie_patch(hw);
        if (flag & ATL1C_PCIE_L0S_L1_DISABLE)
                atl1c_disable_l0s_l1(hw);

        msleep(5);
}

/**
 * atl1c_irq_enable - Enable default interrupt generation settings
 * @adapter: board private structure
 */
static inline void atl1c_irq_enable(struct atl1c_adapter *adapter)
{
        if (likely(atomic_dec_and_test(&adapter->irq_sem))) {
                AT_WRITE_REG(&adapter->hw, REG_ISR, 0x7FFFFFFF);
                AT_WRITE_REG(&adapter->hw, REG_IMR, adapter->hw.intr_mask);
                AT_WRITE_FLUSH(&adapter->hw);
        }
}

/**
 * atl1c_irq_disable - Mask off interrupt generation on the NIC
 * @adapter: board private structure
 */
static inline void atl1c_irq_disable(struct atl1c_adapter *adapter)
{
        atomic_inc(&adapter->irq_sem);
        AT_WRITE_REG(&adapter->hw, REG_IMR, 0);
        AT_WRITE_REG(&adapter->hw, REG_ISR, ISR_DIS_INT);
        AT_WRITE_FLUSH(&adapter->hw);
        synchronize_irq(adapter->pdev->irq);
}

/*
 * atl1c_wait_until_idle - wait up to AT_HW_MAX_IDLE_DELAY reads
 * of the idle status register until the device is actually idle
 */
static u32 atl1c_wait_until_idle(struct atl1c_hw *hw, u32 modu_ctrl)
{
        int timeout;
        u32 data;

        for (timeout = 0; timeout < AT_HW_MAX_IDLE_DELAY; timeout++) {
                AT_READ_REG(hw, REG_IDLE_STATUS, &data);
                if ((data & modu_ctrl) == 0)
                        return 0;
                msleep(1);
        }
        return data;
}

/**
 * atl1c_phy_config - Timer Call-back
 * @t: timer list containing pointer to netdev cast into an unsigned long
 */
static void atl1c_phy_config(struct timer_list *t)
{
        struct atl1c_adapter *adapter = timer_container_of(adapter, t,
                                                           phy_config_timer);
        struct atl1c_hw *hw = &adapter->hw;
        unsigned long flags;

        spin_lock_irqsave(&adapter->mdio_lock, flags);
        atl1c_restart_autoneg(hw);
        spin_unlock_irqrestore(&adapter->mdio_lock, flags);
}

void atl1c_reinit_locked(struct atl1c_adapter *adapter)
{
        atl1c_down(adapter);
        atl1c_up(adapter);
        clear_bit(__AT_RESETTING, &adapter->flags);
}

static void atl1c_check_link_status(struct atl1c_adapter *adapter)
{
        struct atl1c_hw *hw = &adapter->hw;
        struct net_device *netdev = adapter->netdev;
        struct pci_dev    *pdev   = adapter->pdev;
        int err;
        unsigned long flags;
        u16 speed, duplex;
        bool link;

        spin_lock_irqsave(&adapter->mdio_lock, flags);
        link = atl1c_get_link_status(hw);
        spin_unlock_irqrestore(&adapter->mdio_lock, flags);

        if (!link) {
                /* link down */
                netif_carrier_off(netdev);
                hw->hibernate = true;
                if (atl1c_reset_mac(hw) != 0)
                        if (netif_msg_hw(adapter))
                                dev_warn(&pdev->dev, "reset mac failed\n");
                atl1c_set_aspm(hw, SPEED_0);
                atl1c_post_phy_linkchg(hw, SPEED_0);
                atl1c_reset_dma_ring(adapter);
                atl1c_configure(adapter);
        } else {
                /* Link Up */
                hw->hibernate = false;
                spin_lock_irqsave(&adapter->mdio_lock, flags);
                err = atl1c_get_speed_and_duplex(hw, &speed, &duplex);
                spin_unlock_irqrestore(&adapter->mdio_lock, flags);
                if (unlikely(err))
                        return;
                /* link result is our setting */
                if (adapter->link_speed != speed ||
                    adapter->link_duplex != duplex) {
                        adapter->link_speed  = speed;
                        adapter->link_duplex = duplex;
                        atl1c_set_aspm(hw, speed);
                        atl1c_post_phy_linkchg(hw, speed);
                        atl1c_start_mac(adapter);
                        if (netif_msg_link(adapter))
                                dev_info(&pdev->dev,
                                        "%s: %s NIC Link is Up<%d Mbps %s>\n",
                                        atl1c_driver_name, netdev->name,
                                        adapter->link_speed,
                                        adapter->link_duplex == FULL_DUPLEX ?
                                        "Full Duplex" : "Half Duplex");
                }
                if (!netif_carrier_ok(netdev))
                        netif_carrier_on(netdev);
        }
}

static void atl1c_link_chg_event(struct atl1c_adapter *adapter)
{
        struct net_device *netdev = adapter->netdev;
        struct pci_dev    *pdev   = adapter->pdev;
        bool link;

        spin_lock(&adapter->mdio_lock);
        link = atl1c_get_link_status(&adapter->hw);
        spin_unlock(&adapter->mdio_lock);
        /* notify upper layer link down ASAP */
        if (!link) {
                if (netif_carrier_ok(netdev)) {
                        /* old link state: Up */
                        netif_carrier_off(netdev);
                        if (netif_msg_link(adapter))
                                dev_info(&pdev->dev,
                                        "%s: %s NIC Link is Down\n",
                                        atl1c_driver_name, netdev->name);
                        adapter->link_speed = SPEED_0;
                }
        }

        set_bit(ATL1C_WORK_EVENT_LINK_CHANGE, &adapter->work_event);
        schedule_work(&adapter->common_task);
}

static void atl1c_common_task(struct work_struct *work)
{
        struct atl1c_adapter *adapter;
        struct net_device *netdev;

        adapter = container_of(work, struct atl1c_adapter, common_task);
        netdev = adapter->netdev;

        if (test_bit(__AT_DOWN, &adapter->flags))
                return;

        if (test_and_clear_bit(ATL1C_WORK_EVENT_RESET, &adapter->work_event)) {
                netif_device_detach(netdev);
                atl1c_down(adapter);
                atl1c_up(adapter);
                netif_device_attach(netdev);
        }

        if (test_and_clear_bit(ATL1C_WORK_EVENT_LINK_CHANGE,
                &adapter->work_event)) {
                atl1c_irq_disable(adapter);
                atl1c_check_link_status(adapter);
                atl1c_irq_enable(adapter);
        }
}


static void atl1c_del_timer(struct atl1c_adapter *adapter)
{
        timer_delete_sync(&adapter->phy_config_timer);
}


/**
 * atl1c_tx_timeout - Respond to a Tx Hang
 * @netdev: network interface device structure
 * @txqueue: index of hanging tx queue
 */
static void atl1c_tx_timeout(struct net_device *netdev, unsigned int txqueue)
{
        struct atl1c_adapter *adapter = netdev_priv(netdev);

        /* Do the reset outside of interrupt context */
        set_bit(ATL1C_WORK_EVENT_RESET, &adapter->work_event);
        schedule_work(&adapter->common_task);
}

/**
 * atl1c_set_multi - Multicast and Promiscuous mode set
 * @netdev: network interface device structure
 *
 * The set_multi entry point is called whenever the multicast address
 * list or the network interface flags are updated.  This routine is
 * responsible for configuring the hardware for proper multicast,
 * promiscuous mode, and all-multi behavior.
 */
static void atl1c_set_multi(struct net_device *netdev)
{
        struct atl1c_adapter *adapter = netdev_priv(netdev);
        struct atl1c_hw *hw = &adapter->hw;
        struct netdev_hw_addr *ha;
        u32 mac_ctrl_data;
        u32 hash_value;

        /* Check for Promiscuous and All Multicast modes */
        AT_READ_REG(hw, REG_MAC_CTRL, &mac_ctrl_data);

        if (netdev->flags & IFF_PROMISC) {
                mac_ctrl_data |= MAC_CTRL_PROMIS_EN;
        } else if (netdev->flags & IFF_ALLMULTI) {
                mac_ctrl_data |= MAC_CTRL_MC_ALL_EN;
                mac_ctrl_data &= ~MAC_CTRL_PROMIS_EN;
        } else {
                mac_ctrl_data &= ~(MAC_CTRL_PROMIS_EN | MAC_CTRL_MC_ALL_EN);
        }

        AT_WRITE_REG(hw, REG_MAC_CTRL, mac_ctrl_data);

        /* clear the old settings from the multicast hash table */
        AT_WRITE_REG(hw, REG_RX_HASH_TABLE, 0);
        AT_WRITE_REG_ARRAY(hw, REG_RX_HASH_TABLE, 1, 0);

        /* comoute mc addresses' hash value ,and put it into hash table */
        netdev_for_each_mc_addr(ha, netdev) {
                hash_value = atl1c_hash_mc_addr(hw, ha->addr);
                atl1c_hash_set(hw, hash_value);
        }
}

static void __atl1c_vlan_mode(netdev_features_t features, u32 *mac_ctrl_data)
{
        if (features & NETIF_F_HW_VLAN_CTAG_RX) {
                /* enable VLAN tag insert/strip */
                *mac_ctrl_data |= MAC_CTRL_RMV_VLAN;
        } else {
                /* disable VLAN tag insert/strip */
                *mac_ctrl_data &= ~MAC_CTRL_RMV_VLAN;
        }
}

static void atl1c_vlan_mode(struct net_device *netdev,
        netdev_features_t features)
{
        struct atl1c_adapter *adapter = netdev_priv(netdev);
        struct pci_dev *pdev = adapter->pdev;
        u32 mac_ctrl_data = 0;

        if (netif_msg_pktdata(adapter))
                dev_dbg(&pdev->dev, "atl1c_vlan_mode\n");

        atl1c_irq_disable(adapter);
        AT_READ_REG(&adapter->hw, REG_MAC_CTRL, &mac_ctrl_data);
        __atl1c_vlan_mode(features, &mac_ctrl_data);
        AT_WRITE_REG(&adapter->hw, REG_MAC_CTRL, mac_ctrl_data);
        atl1c_irq_enable(adapter);
}

static void atl1c_restore_vlan(struct atl1c_adapter *adapter)
{
        struct pci_dev *pdev = adapter->pdev;

        if (netif_msg_pktdata(adapter))
                dev_dbg(&pdev->dev, "atl1c_restore_vlan\n");
        atl1c_vlan_mode(adapter->netdev, adapter->netdev->features);
}

/**
 * atl1c_set_mac_addr - Change the Ethernet Address of the NIC
 * @netdev: network interface device structure
 * @p: pointer to an address structure
 *
 * Returns 0 on success, negative on failure
 */
static int atl1c_set_mac_addr(struct net_device *netdev, void *p)
{
        struct atl1c_adapter *adapter = netdev_priv(netdev);
        struct sockaddr *addr = p;

        if (!is_valid_ether_addr(addr->sa_data))
                return -EADDRNOTAVAIL;

        if (netif_running(netdev))
                return -EBUSY;

        eth_hw_addr_set(netdev, addr->sa_data);
        memcpy(adapter->hw.mac_addr, addr->sa_data, netdev->addr_len);

        atl1c_hw_set_mac_addr(&adapter->hw, adapter->hw.mac_addr);

        return 0;
}

static void atl1c_set_rxbufsize(struct atl1c_adapter *adapter,
                                struct net_device *dev)
{
        int mtu = dev->mtu;

        adapter->rx_buffer_len = mtu > AT_RX_BUF_SIZE ?
                roundup(mtu + ETH_HLEN + ETH_FCS_LEN + VLAN_HLEN, 8) : AT_RX_BUF_SIZE;
}

static netdev_features_t atl1c_fix_features(struct net_device *netdev,
        netdev_features_t features)
{
        struct atl1c_adapter *adapter = netdev_priv(netdev);
        struct atl1c_hw *hw = &adapter->hw;

        /*
         * Since there is no support for separate rx/tx vlan accel
         * enable/disable make sure tx flag is always in same state as rx.
         */
        if (features & NETIF_F_HW_VLAN_CTAG_RX)
                features |= NETIF_F_HW_VLAN_CTAG_TX;
        else
                features &= ~NETIF_F_HW_VLAN_CTAG_TX;

        if (hw->nic_type != athr_mt) {
                if (netdev->mtu > MAX_TSO_FRAME_SIZE)
                        features &= ~(NETIF_F_TSO | NETIF_F_TSO6);
        }

        return features;
}

static int atl1c_set_features(struct net_device *netdev,
        netdev_features_t features)
{
        netdev_features_t changed = netdev->features ^ features;

        if (changed & NETIF_F_HW_VLAN_CTAG_RX)
                atl1c_vlan_mode(netdev, features);

        return 0;
}

static void atl1c_set_max_mtu(struct net_device *netdev)
{
        struct atl1c_adapter *adapter = netdev_priv(netdev);
        struct atl1c_hw *hw = &adapter->hw;

        switch (hw->nic_type) {
        /* These (GbE) devices support jumbo packets, max_mtu 6122 */
        case athr_l1c:
        case athr_l1d:
        case athr_l1d_2:
                netdev->max_mtu = MAX_JUMBO_FRAME_SIZE -
                        (ETH_HLEN + ETH_FCS_LEN + VLAN_HLEN);
                break;
        case athr_mt:
                netdev->max_mtu = 9500;
                break;
                /* The 10/100 devices don't support jumbo packets, max_mtu 1500 */
        default:
                netdev->max_mtu = ETH_DATA_LEN;
                break;
        }
}

/**
 * atl1c_change_mtu - Change the Maximum Transfer Unit
 * @netdev: network interface device structure
 * @new_mtu: new value for maximum frame size
 *
 * Returns 0 on success, negative on failure
 */
static int atl1c_change_mtu(struct net_device *netdev, int new_mtu)
{
        struct atl1c_adapter *adapter = netdev_priv(netdev);

        /* set MTU */
        if (netif_running(netdev)) {
                while (test_and_set_bit(__AT_RESETTING, &adapter->flags))
                        msleep(1);
                WRITE_ONCE(netdev->mtu, new_mtu);
                adapter->hw.max_frame_size = new_mtu;
                atl1c_set_rxbufsize(adapter, netdev);
                atl1c_down(adapter);
                netdev_update_features(netdev);
                atl1c_up(adapter);
                clear_bit(__AT_RESETTING, &adapter->flags);
        }
        return 0;
}

/*
 *  caller should hold mdio_lock
 */
static int atl1c_mdio_read(struct net_device *netdev, int phy_id, int reg_num)
{
        struct atl1c_adapter *adapter = netdev_priv(netdev);
        u16 result;

        atl1c_read_phy_reg(&adapter->hw, reg_num, &result);
        return result;
}

static void atl1c_mdio_write(struct net_device *netdev, int phy_id,
                             int reg_num, int val)
{
        struct atl1c_adapter *adapter = netdev_priv(netdev);

        atl1c_write_phy_reg(&adapter->hw, reg_num, val);
}

static int atl1c_mii_ioctl(struct net_device *netdev,
                           struct ifreq *ifr, int cmd)
{
        struct atl1c_adapter *adapter = netdev_priv(netdev);
        struct pci_dev *pdev = adapter->pdev;
        struct mii_ioctl_data *data = if_mii(ifr);
        unsigned long flags;
        int retval = 0;

        if (!netif_running(netdev))
                return -EINVAL;

        spin_lock_irqsave(&adapter->mdio_lock, flags);
        switch (cmd) {
        case SIOCGMIIPHY:
                data->phy_id = 0;
                break;

        case SIOCGMIIREG:
                if (atl1c_read_phy_reg(&adapter->hw, data->reg_num & 0x1F,
                                    &data->val_out)) {
                        retval = -EIO;
                        goto out;
                }
                break;

        case SIOCSMIIREG:
                if (data->reg_num & ~(0x1F)) {
                        retval = -EFAULT;
                        goto out;
                }

                dev_dbg(&pdev->dev, "<atl1c_mii_ioctl> write %x %x",
                                data->reg_num, data->val_in);
                if (atl1c_write_phy_reg(&adapter->hw,
                                     data->reg_num, data->val_in)) {
                        retval = -EIO;
                        goto out;
                }
                break;

        default:
                retval = -EOPNOTSUPP;
                break;
        }
out:
        spin_unlock_irqrestore(&adapter->mdio_lock, flags);
        return retval;
}

static int atl1c_ioctl(struct net_device *netdev, struct ifreq *ifr, int cmd)
{
        switch (cmd) {
        case SIOCGMIIPHY:
        case SIOCGMIIREG:
        case SIOCSMIIREG:
                return atl1c_mii_ioctl(netdev, ifr, cmd);
        default:
                return -EOPNOTSUPP;
        }
}

/**
 * atl1c_alloc_queues - Allocate memory for all rings
 * @adapter: board private structure to initialize
 *
 */
static int atl1c_alloc_queues(struct atl1c_adapter *adapter)
{
        return 0;
}

static enum atl1c_nic_type atl1c_get_mac_type(struct pci_dev *pdev,
                                              u8 __iomem *hw_addr)
{
        switch (pdev->device) {
        case PCI_DEVICE_ID_ATTANSIC_L2C:
                return athr_l2c;
        case PCI_DEVICE_ID_ATTANSIC_L1C:
                return athr_l1c;
        case PCI_DEVICE_ID_ATHEROS_L2C_B:
                return athr_l2c_b;
        case PCI_DEVICE_ID_ATHEROS_L2C_B2:
                return athr_l2c_b2;
        case PCI_DEVICE_ID_ATHEROS_L1D:
                return athr_l1d;
        case PCI_DEVICE_ID_ATHEROS_L1D_2_0:
                if (readl(hw_addr + REG_MT_MAGIC) == MT_MAGIC)
                        return athr_mt;
                return athr_l1d_2;
        default:
                return athr_l1c;
        }
}

static int atl1c_setup_mac_funcs(struct atl1c_hw *hw)
{
        u32 link_ctrl_data;

        AT_READ_REG(hw, REG_LINK_CTRL, &link_ctrl_data);

        hw->ctrl_flags = ATL1C_INTR_MODRT_ENABLE  |
                         ATL1C_TXQ_MODE_ENHANCE;
        hw->ctrl_flags |= ATL1C_ASPM_L0S_SUPPORT |
                          ATL1C_ASPM_L1_SUPPORT;
        hw->ctrl_flags |= ATL1C_ASPM_CTRL_MON;

        if (hw->nic_type == athr_l1c ||
            hw->nic_type == athr_l1d ||
            hw->nic_type == athr_l1d_2)
                hw->link_cap_flags |= ATL1C_LINK_CAP_1000M;
        return 0;
}

struct atl1c_platform_patch {
        u16 pci_did;
        u8  pci_revid;
        u16 subsystem_vid;
        u16 subsystem_did;
        u32 patch_flag;
#define ATL1C_LINK_PATCH        0x1
};
static const struct atl1c_platform_patch plats[] = {
{0x2060, 0xC1, 0x1019, 0x8152, 0x1},
{0x2060, 0xC1, 0x1019, 0x2060, 0x1},
{0x2060, 0xC1, 0x1019, 0xE000, 0x1},
{0x2062, 0xC0, 0x1019, 0x8152, 0x1},
{0x2062, 0xC0, 0x1019, 0x2062, 0x1},
{0x2062, 0xC0, 0x1458, 0xE000, 0x1},
{0x2062, 0xC1, 0x1019, 0x8152, 0x1},
{0x2062, 0xC1, 0x1019, 0x2062, 0x1},
{0x2062, 0xC1, 0x1458, 0xE000, 0x1},
{0x2062, 0xC1, 0x1565, 0x2802, 0x1},
{0x2062, 0xC1, 0x1565, 0x2801, 0x1},
{0x1073, 0xC0, 0x1019, 0x8151, 0x1},
{0x1073, 0xC0, 0x1019, 0x1073, 0x1},
{0x1073, 0xC0, 0x1458, 0xE000, 0x1},
{0x1083, 0xC0, 0x1458, 0xE000, 0x1},
{0x1083, 0xC0, 0x1019, 0x8151, 0x1},
{0x1083, 0xC0, 0x1019, 0x1083, 0x1},
{0x1083, 0xC0, 0x1462, 0x7680, 0x1},
{0x1083, 0xC0, 0x1565, 0x2803, 0x1},
{0},
};

static void atl1c_patch_assign(struct atl1c_hw *hw)
{
        struct pci_dev  *pdev = hw->adapter->pdev;
        u32 misc_ctrl;
        int i = 0;

        hw->msi_lnkpatch = false;

        while (plats[i].pci_did != 0) {
                if (plats[i].pci_did == hw->device_id &&
                    plats[i].pci_revid == hw->revision_id &&
                    plats[i].subsystem_vid == hw->subsystem_vendor_id &&
                    plats[i].subsystem_did == hw->subsystem_id) {
                        if (plats[i].patch_flag & ATL1C_LINK_PATCH)
                                hw->msi_lnkpatch = true;
                }
                i++;
        }

        if (hw->device_id == PCI_DEVICE_ID_ATHEROS_L2C_B2 &&
            hw->revision_id == L2CB_V21) {
                /* config access mode */
                pci_write_config_dword(pdev, REG_PCIE_IND_ACC_ADDR,
                                       REG_PCIE_DEV_MISC_CTRL);
                pci_read_config_dword(pdev, REG_PCIE_IND_ACC_DATA, &misc_ctrl);
                misc_ctrl &= ~0x100;
                pci_write_config_dword(pdev, REG_PCIE_IND_ACC_ADDR,
                                       REG_PCIE_DEV_MISC_CTRL);
                pci_write_config_dword(pdev, REG_PCIE_IND_ACC_DATA, misc_ctrl);
        }
}
/**
 * atl1c_sw_init - Initialize general software structures (struct atl1c_adapter)
 * @adapter: board private structure to initialize
 *
 * atl1c_sw_init initializes the Adapter private data structure.
 * Fields are initialized based on PCI device information and
 * OS network device settings (MTU size).
 */
static int atl1c_sw_init(struct atl1c_adapter *adapter)
{
        struct atl1c_hw *hw   = &adapter->hw;
        struct pci_dev  *pdev = adapter->pdev;
        u32 revision;
        int i;

        adapter->wol = 0;
        device_set_wakeup_enable(&pdev->dev, false);
        adapter->link_speed = SPEED_0;
        adapter->link_duplex = FULL_DUPLEX;
        adapter->tpd_ring[0].count = 1024;
        adapter->rfd_ring[0].count = 512;

        hw->vendor_id = pdev->vendor;
        hw->device_id = pdev->device;
        hw->subsystem_vendor_id = pdev->subsystem_vendor;
        hw->subsystem_id = pdev->subsystem_device;
        pci_read_config_dword(pdev, PCI_CLASS_REVISION, &revision);
        hw->revision_id = revision & 0xFF;
        /* before link up, we assume hibernate is true */
        hw->hibernate = true;
        hw->media_type = MEDIA_TYPE_AUTO_SENSOR;
        if (atl1c_setup_mac_funcs(hw) != 0) {
                dev_err(&pdev->dev, "set mac function pointers failed\n");
                return -1;
        }
        atl1c_patch_assign(hw);

        hw->intr_mask = IMR_NORMAL_MASK;
        for (i = 0; i < adapter->tx_queue_count; ++i)
                hw->intr_mask |= atl1c_qregs[i].tx_isr;
        for (i = 0; i < adapter->rx_queue_count; ++i)
                hw->intr_mask |= atl1c_qregs[i].rx_isr;
        hw->phy_configured = false;
        hw->preamble_len = 7;
        hw->max_frame_size = adapter->netdev->mtu;
        hw->autoneg_advertised = ADVERTISED_Autoneg;
        hw->indirect_tab = 0xE4E4E4E4;
        hw->base_cpu = 0;

        hw->ict = 50000;                /* 100ms */
        hw->smb_timer = 200000;         /* 400ms */
        hw->rx_imt = 200;
        hw->tx_imt = 1000;

        hw->tpd_burst = 5;
        hw->rfd_burst = 8;
        hw->dma_order = atl1c_dma_ord_out;
        hw->dmar_block = atl1c_dma_req_1024;

        if (atl1c_alloc_queues(adapter)) {
                dev_err(&pdev->dev, "Unable to allocate memory for queues\n");
                return -ENOMEM;
        }
        /* TODO */
        atl1c_set_rxbufsize(adapter, adapter->netdev);
        atomic_set(&adapter->irq_sem, 1);
        spin_lock_init(&adapter->mdio_lock);
        spin_lock_init(&adapter->hw.intr_mask_lock);
        set_bit(__AT_DOWN, &adapter->flags);

        return 0;
}

static inline void atl1c_clean_buffer(struct pci_dev *pdev,
                                      struct atl1c_buffer *buffer_info,
                                      int budget)
{
        u16 pci_driection;
        if (buffer_info->flags & ATL1C_BUFFER_FREE)
                return;
        if (buffer_info->dma) {
                if (buffer_info->flags & ATL1C_PCIMAP_FROMDEVICE)
                        pci_driection = DMA_FROM_DEVICE;
                else
                        pci_driection = DMA_TO_DEVICE;

                if (buffer_info->flags & ATL1C_PCIMAP_SINGLE)
                        dma_unmap_single(&pdev->dev, buffer_info->dma,
                                         buffer_info->length, pci_driection);
                else if (buffer_info->flags & ATL1C_PCIMAP_PAGE)
                        dma_unmap_page(&pdev->dev, buffer_info->dma,
                                       buffer_info->length, pci_driection);
        }
        if (buffer_info->skb)
                napi_consume_skb(buffer_info->skb, budget);
        buffer_info->dma = 0;
        buffer_info->skb = NULL;
        ATL1C_SET_BUFFER_STATE(buffer_info, ATL1C_BUFFER_FREE);
}
/**
 * atl1c_clean_tx_ring - Free Tx-skb
 * @adapter: board private structure
 * @queue: idx of transmit queue
 */
static void atl1c_clean_tx_ring(struct atl1c_adapter *adapter,
                                u32 queue)
{
        struct atl1c_tpd_ring *tpd_ring = &adapter->tpd_ring[queue];
        struct atl1c_buffer *buffer_info;
        struct pci_dev *pdev = adapter->pdev;
        u16 index, ring_count;

        ring_count = tpd_ring->count;
        for (index = 0; index < ring_count; index++) {
                buffer_info = &tpd_ring->buffer_info[index];
                atl1c_clean_buffer(pdev, buffer_info, 0);
        }

        netdev_tx_reset_queue(netdev_get_tx_queue(adapter->netdev, queue));

        /* Zero out Tx-buffers */
        memset(tpd_ring->desc, 0, sizeof(struct atl1c_tpd_desc) *
                ring_count);
        atomic_set(&tpd_ring->next_to_clean, 0);
        tpd_ring->next_to_use = 0;
}

/**
 * atl1c_clean_rx_ring - Free rx-reservation skbs
 * @adapter: board private structure
 * @queue: idx of transmit queue
 */
static void atl1c_clean_rx_ring(struct atl1c_adapter *adapter, u32 queue)
{
        struct atl1c_rfd_ring *rfd_ring = &adapter->rfd_ring[queue];
        struct atl1c_rrd_ring *rrd_ring = &adapter->rrd_ring[queue];
        struct atl1c_buffer *buffer_info;
        struct pci_dev *pdev = adapter->pdev;
        int j;

        for (j = 0; j < rfd_ring->count; j++) {
                buffer_info = &rfd_ring->buffer_info[j];
                atl1c_clean_buffer(pdev, buffer_info, 0);
        }
        /* zero out the descriptor ring */
        memset(rfd_ring->desc, 0, rfd_ring->size);
        rfd_ring->next_to_clean = 0;
        rfd_ring->next_to_use = 0;
        rrd_ring->next_to_use = 0;
        rrd_ring->next_to_clean = 0;
}

/*
 * Read / Write Ptr Initialize:
 */
static void atl1c_init_ring_ptrs(struct atl1c_adapter *adapter)
{
        struct atl1c_tpd_ring *tpd_ring = adapter->tpd_ring;
        struct atl1c_rfd_ring *rfd_ring = adapter->rfd_ring;
        struct atl1c_rrd_ring *rrd_ring = adapter->rrd_ring;
        struct atl1c_buffer *buffer_info;
        int i, j;

        for (i = 0; i < adapter->tx_queue_count; i++) {
                tpd_ring[i].next_to_use = 0;
                atomic_set(&tpd_ring[i].next_to_clean, 0);
                buffer_info = tpd_ring[i].buffer_info;
                for (j = 0; j < tpd_ring->count; j++)
                        ATL1C_SET_BUFFER_STATE(&buffer_info[i],
                                               ATL1C_BUFFER_FREE);
        }
        for (i = 0; i < adapter->rx_queue_count; i++) {
                rfd_ring[i].next_to_use = 0;
                rfd_ring[i].next_to_clean = 0;
                rrd_ring[i].next_to_use = 0;
                rrd_ring[i].next_to_clean = 0;
                for (j = 0; j < rfd_ring[i].count; j++) {
                        buffer_info = &rfd_ring[i].buffer_info[j];
                        ATL1C_SET_BUFFER_STATE(buffer_info, ATL1C_BUFFER_FREE);
                }
        }
}

/**
 * atl1c_free_ring_resources - Free Tx / RX descriptor Resources
 * @adapter: board private structure
 *
 * Free all transmit software resources
 */
static void atl1c_free_ring_resources(struct atl1c_adapter *adapter)
{
        struct pci_dev *pdev = adapter->pdev;

        dma_free_coherent(&pdev->dev, adapter->ring_header.size,
                          adapter->ring_header.desc, adapter->ring_header.dma);
        adapter->ring_header.desc = NULL;

        /* Note: just free tdp_ring.buffer_info,
         * it contain rfd_ring.buffer_info, do not double free
         */
        if (adapter->tpd_ring[0].buffer_info) {
                kfree(adapter->tpd_ring[0].buffer_info);
                adapter->tpd_ring[0].buffer_info = NULL;
        }
}

/**
 * atl1c_setup_ring_resources - allocate Tx / RX descriptor resources
 * @adapter: board private structure
 *
 * Return 0 on success, negative on failure
 */
static int atl1c_setup_ring_resources(struct atl1c_adapter *adapter)
{
        struct pci_dev *pdev = adapter->pdev;
        struct atl1c_tpd_ring *tpd_ring = adapter->tpd_ring;
        struct atl1c_rfd_ring *rfd_ring = adapter->rfd_ring;
        struct atl1c_rrd_ring *rrd_ring = adapter->rrd_ring;
        struct atl1c_ring_header *ring_header = &adapter->ring_header;
        int tqc = adapter->tx_queue_count;
        int rqc = adapter->rx_queue_count;
        int size;
        int i;
        int count = 0;
        u32 offset = 0;

        /* Even though only one tpd queue is actually used, the "high"
         * priority tpd queue also gets initialized
         */
        if (tqc == 1)
                tqc = 2;

        for (i = 1; i < tqc; i++)
                tpd_ring[i].count = tpd_ring[0].count;

        size = sizeof(struct atl1c_buffer) * (tpd_ring->count * tqc +
                                              rfd_ring->count * rqc);
        tpd_ring->buffer_info = kzalloc(size, GFP_KERNEL);
        if (unlikely(!tpd_ring->buffer_info))
                goto err_nomem;

        for (i = 0; i < tqc; i++) {
                tpd_ring[i].adapter = adapter;
                tpd_ring[i].num = i;
                tpd_ring[i].buffer_info = (tpd_ring->buffer_info + count);
                count += tpd_ring[i].count;
        }

        for (i = 0; i < rqc; i++) {
                rrd_ring[i].adapter = adapter;
                rrd_ring[i].num = i;
                rrd_ring[i].count = rfd_ring[0].count;
                rfd_ring[i].count = rfd_ring[0].count;
                rfd_ring[i].buffer_info = (tpd_ring->buffer_info + count);
                count += rfd_ring->count;
        }

        /*
         * real ring DMA buffer
         * each ring/block may need up to 8 bytes for alignment, hence the
         * additional bytes tacked onto the end.
         */
        ring_header->size =
                sizeof(struct atl1c_tpd_desc) * tpd_ring->count * tqc +
                sizeof(struct atl1c_rx_free_desc) * rfd_ring->count * rqc +
                sizeof(struct atl1c_recv_ret_status) * rfd_ring->count * rqc +
                8 * 4;

        ring_header->desc = dma_alloc_coherent(&pdev->dev, ring_header->size,
                                               &ring_header->dma, GFP_KERNEL);
        if (unlikely(!ring_header->desc)) {
                dev_err(&pdev->dev, "could not get memory for DMA buffer\n");
                goto err_nomem;
        }
        /* init TPD ring */

        tpd_ring[0].dma = roundup(ring_header->dma, 8);
        offset = tpd_ring[0].dma - ring_header->dma;
        for (i = 0; i < tqc; i++) {
                tpd_ring[i].dma = ring_header->dma + offset;
                tpd_ring[i].desc = (u8 *)ring_header->desc + offset;
                tpd_ring[i].size =
                        sizeof(struct atl1c_tpd_desc) * tpd_ring[i].count;
                offset += roundup(tpd_ring[i].size, 8);
        }
        for (i = 0; i < rqc; i++) {
                /* init RFD ring */
                rfd_ring[i].dma = ring_header->dma + offset;
                rfd_ring[i].desc = (u8 *)ring_header->desc + offset;
                rfd_ring[i].size = sizeof(struct atl1c_rx_free_desc) *
                        rfd_ring[i].count;
                offset += roundup(rfd_ring[i].size, 8);

                /* init RRD ring */
                rrd_ring[i].dma = ring_header->dma + offset;
                rrd_ring[i].desc = (u8 *)ring_header->desc + offset;
                rrd_ring[i].size = sizeof(struct atl1c_recv_ret_status) *
                        rrd_ring[i].count;
                offset += roundup(rrd_ring[i].size, 8);
        }

        return 0;

err_nomem:
        kfree(tpd_ring->buffer_info);
        return -ENOMEM;
}

static void atl1c_configure_des_ring(struct atl1c_adapter *adapter)
{
        struct atl1c_hw *hw = &adapter->hw;
        struct atl1c_rfd_ring *rfd_ring = adapter->rfd_ring;
        struct atl1c_rrd_ring *rrd_ring = adapter->rrd_ring;
        struct atl1c_tpd_ring *tpd_ring = adapter->tpd_ring;
        int i;
        int tx_queue_count = adapter->tx_queue_count;

        if (tx_queue_count == 1)
                tx_queue_count = 2;

        /* TPD */
        AT_WRITE_REG(hw, REG_TX_BASE_ADDR_HI,
                     (u32)((tpd_ring[0].dma & AT_DMA_HI_ADDR_MASK) >> 32));
        /* just enable normal priority TX queue */
        for (i = 0; i < tx_queue_count; i++) {
                AT_WRITE_REG(hw, atl1c_qregs[i].tpd_addr_lo,
                             (u32)(tpd_ring[i].dma & AT_DMA_LO_ADDR_MASK));
        }
        AT_WRITE_REG(hw, REG_TPD_RING_SIZE,
                        (u32)(tpd_ring[0].count & TPD_RING_SIZE_MASK));


        /* RFD */
        AT_WRITE_REG(hw, REG_RX_BASE_ADDR_HI,
                     (u32)((rfd_ring->dma & AT_DMA_HI_ADDR_MASK) >> 32));
        for (i = 0; i < adapter->rx_queue_count; i++) {
                AT_WRITE_REG(hw, atl1c_qregs[i].rfd_addr_lo,
                             (u32)(rfd_ring[i].dma & AT_DMA_LO_ADDR_MASK));
        }

        AT_WRITE_REG(hw, REG_RFD_RING_SIZE,
                        rfd_ring->count & RFD_RING_SIZE_MASK);
        AT_WRITE_REG(hw, REG_RX_BUF_SIZE,
                        adapter->rx_buffer_len & RX_BUF_SIZE_MASK);

        /* RRD */
        for (i = 0; i < adapter->rx_queue_count; i++) {
                AT_WRITE_REG(hw, atl1c_qregs[i].rrd_addr_lo,
                             (u32)(rrd_ring[i].dma & AT_DMA_LO_ADDR_MASK));
        }
        AT_WRITE_REG(hw, REG_RRD_RING_SIZE,
                        (rrd_ring->count & RRD_RING_SIZE_MASK));

        if (hw->nic_type == athr_l2c_b) {
                AT_WRITE_REG(hw, REG_SRAM_RXF_LEN, 0x02a0L);
                AT_WRITE_REG(hw, REG_SRAM_TXF_LEN, 0x0100L);
                AT_WRITE_REG(hw, REG_SRAM_RXF_ADDR, 0x029f0000L);
                AT_WRITE_REG(hw, REG_SRAM_RFD0_INFO, 0x02bf02a0L);
                AT_WRITE_REG(hw, REG_SRAM_TXF_ADDR, 0x03bf02c0L);
                AT_WRITE_REG(hw, REG_SRAM_TRD_ADDR, 0x03df03c0L);
                AT_WRITE_REG(hw, REG_TXF_WATER_MARK, 0);        /* TX watermark, to enter l1 state.*/
                AT_WRITE_REG(hw, REG_RXD_DMA_CTRL, 0);          /* RXD threshold.*/
        }
        /* Load all of base address above */
        AT_WRITE_REG(hw, REG_LOAD_PTR, 1);
}

static void atl1c_configure_tx(struct atl1c_adapter *adapter)
{
        struct atl1c_hw *hw = &adapter->hw;
        int max_pay_load;
        u16 tx_offload_thresh;
        u32 txq_ctrl_data;

        tx_offload_thresh = MAX_TSO_FRAME_SIZE;
        AT_WRITE_REG(hw, REG_TX_TSO_OFFLOAD_THRESH,
                (tx_offload_thresh >> 3) & TX_TSO_OFFLOAD_THRESH_MASK);
        max_pay_load = pcie_get_readrq(adapter->pdev) >> 8;
        hw->dmar_block = min_t(u32, max_pay_load, hw->dmar_block);
        /*
         * if BIOS had changed the dam-read-max-length to an invalid value,
         * restore it to default value
         */
        if (hw->dmar_block < DEVICE_CTRL_MAXRRS_MIN) {
                pcie_set_readrq(adapter->pdev, 128 << DEVICE_CTRL_MAXRRS_MIN);
                hw->dmar_block = DEVICE_CTRL_MAXRRS_MIN;
        }
        txq_ctrl_data =
                hw->nic_type == athr_l2c_b || hw->nic_type == athr_l2c_b2 ?
                L2CB_TXQ_CFGV : L1C_TXQ_CFGV;

        AT_WRITE_REG(hw, REG_TXQ_CTRL, txq_ctrl_data);
}

static void atl1c_configure_rx(struct atl1c_adapter *adapter)
{
        struct atl1c_hw *hw = &adapter->hw;
        u32 rxq_ctrl_data;

        rxq_ctrl_data = (hw->rfd_burst & RXQ_RFD_BURST_NUM_MASK) <<
                        RXQ_RFD_BURST_NUM_SHIFT;

        if (hw->ctrl_flags & ATL1C_RX_IPV6_CHKSUM)
                rxq_ctrl_data |= IPV6_CHKSUM_CTRL_EN;

        /* aspm for gigabit */
        if (hw->nic_type != athr_l1d_2 && (hw->device_id & 1) != 0)
                rxq_ctrl_data = FIELD_SETX(rxq_ctrl_data, ASPM_THRUPUT_LIMIT,
                        ASPM_THRUPUT_LIMIT_100M);

        AT_WRITE_REG(hw, REG_RXQ_CTRL, rxq_ctrl_data);
}

static void atl1c_configure_dma(struct atl1c_adapter *adapter)
{
        struct atl1c_hw *hw = &adapter->hw;
        u32 dma_ctrl_data;

        dma_ctrl_data = FIELDX(DMA_CTRL_RORDER_MODE, DMA_CTRL_RORDER_MODE_OUT) |
                DMA_CTRL_RREQ_PRI_DATA |
                FIELDX(DMA_CTRL_RREQ_BLEN, hw->dmar_block) |
                FIELDX(DMA_CTRL_WDLY_CNT, DMA_CTRL_WDLY_CNT_DEF) |
                FIELDX(DMA_CTRL_RDLY_CNT, DMA_CTRL_RDLY_CNT_DEF);

        AT_WRITE_REG(hw, REG_DMA_CTRL, dma_ctrl_data);
}

/*
 * Stop the mac, transmit and receive units
 * hw - Struct containing variables accessed by shared code
 * return : 0  or  idle status (if error)
 */
static int atl1c_stop_mac(struct atl1c_hw *hw)
{
        u32 data;

        AT_READ_REG(hw, REG_RXQ_CTRL, &data);
        data &= ~RXQ_CTRL_EN;
        AT_WRITE_REG(hw, REG_RXQ_CTRL, data);

        AT_READ_REG(hw, REG_TXQ_CTRL, &data);
        data &= ~TXQ_CTRL_EN;
        AT_WRITE_REG(hw, REG_TXQ_CTRL, data);

        atl1c_wait_until_idle(hw, IDLE_STATUS_RXQ_BUSY | IDLE_STATUS_TXQ_BUSY);

        AT_READ_REG(hw, REG_MAC_CTRL, &data);
        data &= ~(MAC_CTRL_TX_EN | MAC_CTRL_RX_EN);
        AT_WRITE_REG(hw, REG_MAC_CTRL, data);

        return (int)atl1c_wait_until_idle(hw,
                IDLE_STATUS_TXMAC_BUSY | IDLE_STATUS_RXMAC_BUSY);
}

static void atl1c_start_mac(struct atl1c_adapter *adapter)
{
        struct atl1c_hw *hw = &adapter->hw;
        u32 mac, txq, rxq;

        hw->mac_duplex = adapter->link_duplex == FULL_DUPLEX;
        hw->mac_speed = adapter->link_speed == SPEED_1000 ?
                atl1c_mac_speed_1000 : atl1c_mac_speed_10_100;

        AT_READ_REG(hw, REG_TXQ_CTRL, &txq);
        AT_READ_REG(hw, REG_RXQ_CTRL, &rxq);
        AT_READ_REG(hw, REG_MAC_CTRL, &mac);

        txq |= TXQ_CTRL_EN;
        rxq |= RXQ_CTRL_EN;
        mac |= MAC_CTRL_TX_EN | MAC_CTRL_TX_FLOW |
               MAC_CTRL_RX_EN | MAC_CTRL_RX_FLOW |
               MAC_CTRL_ADD_CRC | MAC_CTRL_PAD |
               MAC_CTRL_BC_EN | MAC_CTRL_SINGLE_PAUSE_EN |
               MAC_CTRL_HASH_ALG_CRC32;
        if (hw->mac_duplex)
                mac |= MAC_CTRL_DUPLX;
        else
                mac &= ~MAC_CTRL_DUPLX;
        mac = FIELD_SETX(mac, MAC_CTRL_SPEED, hw->mac_speed);
        mac = FIELD_SETX(mac, MAC_CTRL_PRMLEN, hw->preamble_len);

        AT_WRITE_REG(hw, REG_TXQ_CTRL, txq);
        AT_WRITE_REG(hw, REG_RXQ_CTRL, rxq);
        AT_WRITE_REG(hw, REG_MAC_CTRL, mac);
}

/*
 * Reset the transmit and receive units; mask and clear all interrupts.
 * hw - Struct containing variables accessed by shared code
 * return : 0  or  idle status (if error)
 */
static int atl1c_reset_mac(struct atl1c_hw *hw)
{
        struct atl1c_adapter *adapter = hw->adapter;
        struct pci_dev *pdev = adapter->pdev;
        u32 ctrl_data = 0;

        atl1c_stop_mac(hw);
        /*
         * Issue Soft Reset to the MAC.  This will reset the chip's
         * transmit, receive, DMA.  It will not effect
         * the current PCI configuration.  The global reset bit is self-
         * clearing, and should clear within a microsecond.
         */
        AT_READ_REG(hw, REG_MASTER_CTRL, &ctrl_data);
        ctrl_data |= MASTER_CTRL_OOB_DIS;
        AT_WRITE_REG(hw, REG_MASTER_CTRL, ctrl_data | MASTER_CTRL_SOFT_RST);

        AT_WRITE_FLUSH(hw);
        msleep(10);
        /* Wait at least 10ms for All module to be Idle */

        if (atl1c_wait_until_idle(hw, IDLE_STATUS_MASK)) {
                dev_err(&pdev->dev,
                        "MAC state machine can't be idle since"
                        " disabled for 10ms second\n");
                return -1;
        }
        AT_WRITE_REG(hw, REG_MASTER_CTRL, ctrl_data);

        /* driver control speed/duplex */
        AT_READ_REG(hw, REG_MAC_CTRL, &ctrl_data);
        AT_WRITE_REG(hw, REG_MAC_CTRL, ctrl_data | MAC_CTRL_SPEED_MODE_SW);

        /* clk switch setting */
        AT_READ_REG(hw, REG_SERDES, &ctrl_data);
        switch (hw->nic_type) {
        case athr_l2c_b:
                ctrl_data &= ~(SERDES_PHY_CLK_SLOWDOWN |
                                SERDES_MAC_CLK_SLOWDOWN);
                AT_WRITE_REG(hw, REG_SERDES, ctrl_data);
                break;
        case athr_l2c_b2:
        case athr_l1d_2:
                ctrl_data |= SERDES_PHY_CLK_SLOWDOWN | SERDES_MAC_CLK_SLOWDOWN;
                AT_WRITE_REG(hw, REG_SERDES, ctrl_data);
                break;
        default:
                break;
        }

        return 0;
}

static void atl1c_disable_l0s_l1(struct atl1c_hw *hw)
{
        u16 ctrl_flags = hw->ctrl_flags;

        hw->ctrl_flags &= ~(ATL1C_ASPM_L0S_SUPPORT | ATL1C_ASPM_L1_SUPPORT);
        atl1c_set_aspm(hw, SPEED_0);
        hw->ctrl_flags = ctrl_flags;
}

/*
 * Set ASPM state.
 * Enable/disable L0s/L1 depend on link state.
 */
static void atl1c_set_aspm(struct atl1c_hw *hw, u16 link_speed)
{
        u32 pm_ctrl_data;
        u32 link_l1_timer;

        AT_READ_REG(hw, REG_PM_CTRL, &pm_ctrl_data);
        pm_ctrl_data &= ~(PM_CTRL_ASPM_L1_EN |
                          PM_CTRL_ASPM_L0S_EN |
                          PM_CTRL_MAC_ASPM_CHK);
        /* L1 timer */
        if (hw->nic_type == athr_l2c_b2 || hw->nic_type == athr_l1d_2) {
                pm_ctrl_data &= ~PMCTRL_TXL1_AFTER_L0S;
                link_l1_timer =
                        link_speed == SPEED_1000 || link_speed == SPEED_100 ?
                        L1D_PMCTRL_L1_ENTRY_TM_16US : 1;
                pm_ctrl_data = FIELD_SETX(pm_ctrl_data,
                        L1D_PMCTRL_L1_ENTRY_TM, link_l1_timer);
        } else {
                link_l1_timer = hw->nic_type == athr_l2c_b ?
                        L2CB1_PM_CTRL_L1_ENTRY_TM : L1C_PM_CTRL_L1_ENTRY_TM;
                if (link_speed != SPEED_1000 && link_speed != SPEED_100)
                        link_l1_timer = 1;
                pm_ctrl_data = FIELD_SETX(pm_ctrl_data,
                        PM_CTRL_L1_ENTRY_TIMER, link_l1_timer);
        }

        /* L0S/L1 enable */
        if ((hw->ctrl_flags & ATL1C_ASPM_L0S_SUPPORT) && link_speed != SPEED_0)
                pm_ctrl_data |= PM_CTRL_ASPM_L0S_EN | PM_CTRL_MAC_ASPM_CHK;
        if (hw->ctrl_flags & ATL1C_ASPM_L1_SUPPORT)
                pm_ctrl_data |= PM_CTRL_ASPM_L1_EN | PM_CTRL_MAC_ASPM_CHK;

        /* l2cb & l1d & l2cb2 & l1d2 */
        if (hw->nic_type == athr_l2c_b || hw->nic_type == athr_l1d ||
            hw->nic_type == athr_l2c_b2 || hw->nic_type == athr_l1d_2) {
                pm_ctrl_data = FIELD_SETX(pm_ctrl_data,
                        PM_CTRL_PM_REQ_TIMER, PM_CTRL_PM_REQ_TO_DEF);
                pm_ctrl_data |= PM_CTRL_RCVR_WT_TIMER |
                                PM_CTRL_SERDES_PD_EX_L1 |
                                PM_CTRL_CLK_SWH_L1;
                pm_ctrl_data &= ~(PM_CTRL_SERDES_L1_EN |
                                  PM_CTRL_SERDES_PLL_L1_EN |
                                  PM_CTRL_SERDES_BUFS_RX_L1_EN |
                                  PM_CTRL_SA_DLY_EN |
                                  PM_CTRL_HOTRST);
                /* disable l0s if link down or l2cb */
                if (link_speed == SPEED_0 || hw->nic_type == athr_l2c_b)
                        pm_ctrl_data &= ~PM_CTRL_ASPM_L0S_EN;
        } else { /* l1c */
                pm_ctrl_data =
                        FIELD_SETX(pm_ctrl_data, PM_CTRL_L1_ENTRY_TIMER, 0);
                if (link_speed != SPEED_0) {
                        pm_ctrl_data |= PM_CTRL_SERDES_L1_EN |
                                        PM_CTRL_SERDES_PLL_L1_EN |
                                        PM_CTRL_SERDES_BUFS_RX_L1_EN;
                        pm_ctrl_data &= ~(PM_CTRL_SERDES_PD_EX_L1 |
                                          PM_CTRL_CLK_SWH_L1 |
                                          PM_CTRL_ASPM_L0S_EN |
                                          PM_CTRL_ASPM_L1_EN);
                } else { /* link down */
                        pm_ctrl_data |= PM_CTRL_CLK_SWH_L1;
                        pm_ctrl_data &= ~(PM_CTRL_SERDES_L1_EN |
                                          PM_CTRL_SERDES_PLL_L1_EN |
                                          PM_CTRL_SERDES_BUFS_RX_L1_EN |
                                          PM_CTRL_ASPM_L0S_EN);
                }
        }
        AT_WRITE_REG(hw, REG_PM_CTRL, pm_ctrl_data);

        return;
}

/**
 * atl1c_configure_mac - Configure Transmit&Receive Unit after Reset
 * @adapter: board private structure
 *
 * Configure the Tx /Rx unit of the MAC after a reset.
 */
static int atl1c_configure_mac(struct atl1c_adapter *adapter)
{
        struct atl1c_hw *hw = &adapter->hw;
        u32 master_ctrl_data = 0;
        u32 intr_modrt_data;
        u32 data;

        AT_READ_REG(hw, REG_MASTER_CTRL, &master_ctrl_data);
        master_ctrl_data &= ~(MASTER_CTRL_TX_ITIMER_EN |
                              MASTER_CTRL_RX_ITIMER_EN |
                              MASTER_CTRL_INT_RDCLR);
        /* clear interrupt status */
        AT_WRITE_REG(hw, REG_ISR, 0xFFFFFFFF);
        /*  Clear any WOL status */
        AT_WRITE_REG(hw, REG_WOL_CTRL, 0);
        /* set Interrupt Clear Timer
         * HW will enable self to assert interrupt event to system after
         * waiting x-time for software to notify it accept interrupt.
         */

        data = CLK_GATING_EN_ALL;
        if (hw->ctrl_flags & ATL1C_CLK_GATING_EN) {
                if (hw->nic_type == athr_l2c_b)
                        data &= ~CLK_GATING_RXMAC_EN;
        } else
                data = 0;
        AT_WRITE_REG(hw, REG_CLK_GATING_CTRL, data);

        AT_WRITE_REG(hw, REG_INT_RETRIG_TIMER,
                hw->ict & INT_RETRIG_TIMER_MASK);

        atl1c_configure_des_ring(adapter);

        if (hw->ctrl_flags & ATL1C_INTR_MODRT_ENABLE) {
                intr_modrt_data = (hw->tx_imt & IRQ_MODRT_TIMER_MASK) <<
                                        IRQ_MODRT_TX_TIMER_SHIFT;
                intr_modrt_data |= (hw->rx_imt & IRQ_MODRT_TIMER_MASK) <<
                                        IRQ_MODRT_RX_TIMER_SHIFT;
                AT_WRITE_REG(hw, REG_IRQ_MODRT_TIMER_INIT, intr_modrt_data);
                master_ctrl_data |=
                        MASTER_CTRL_TX_ITIMER_EN | MASTER_CTRL_RX_ITIMER_EN;
        }

        if (hw->ctrl_flags & ATL1C_INTR_CLEAR_ON_READ)
                master_ctrl_data |= MASTER_CTRL_INT_RDCLR;

        master_ctrl_data |= MASTER_CTRL_SA_TIMER_EN;
        AT_WRITE_REG(hw, REG_MASTER_CTRL, master_ctrl_data);

        AT_WRITE_REG(hw, REG_SMB_STAT_TIMER,
                hw->smb_timer & SMB_STAT_TIMER_MASK);

        /* set MTU */
        AT_WRITE_REG(hw, REG_MTU, hw->max_frame_size + ETH_HLEN +
                        VLAN_HLEN + ETH_FCS_LEN);

        atl1c_configure_tx(adapter);
        atl1c_configure_rx(adapter);
        atl1c_configure_dma(adapter);

        return 0;
}

static int atl1c_configure(struct atl1c_adapter *adapter)
{
        struct net_device *netdev = adapter->netdev;
        int num;
        int i;

        if (adapter->hw.nic_type == athr_mt) {
                u32 mode;

                AT_READ_REG(&adapter->hw, REG_MT_MODE, &mode);
                if (adapter->rx_queue_count == 4)
                        mode |= MT_MODE_4Q;
                else
                        mode &= ~MT_MODE_4Q;
                AT_WRITE_REG(&adapter->hw, REG_MT_MODE, mode);
        }

        atl1c_init_ring_ptrs(adapter);
        atl1c_set_multi(netdev);
        atl1c_restore_vlan(adapter);

        for (i = 0; i < adapter->rx_queue_count; ++i) {
                num = atl1c_alloc_rx_buffer(adapter, i, false);
                if (unlikely(num == 0))
                        return -ENOMEM;
        }

        if (atl1c_configure_mac(adapter))
                return -EIO;

        return 0;
}

static void atl1c_update_hw_stats(struct atl1c_adapter *adapter)
{
        u16 hw_reg_addr = 0;
        unsigned long *stats_item = NULL;
        u32 data;

        /* update rx status */
        hw_reg_addr = REG_MAC_RX_STATUS_BIN;
        stats_item  = &adapter->hw_stats.rx_ok;
        while (hw_reg_addr <= REG_MAC_RX_STATUS_END) {
                AT_READ_REG(&adapter->hw, hw_reg_addr, &data);
                *stats_item += data;
                stats_item++;
                hw_reg_addr += 4;
        }
/* update tx status */
        hw_reg_addr = REG_MAC_TX_STATUS_BIN;
        stats_item  = &adapter->hw_stats.tx_ok;
        while (hw_reg_addr <= REG_MAC_TX_STATUS_END) {
                AT_READ_REG(&adapter->hw, hw_reg_addr, &data);
                *stats_item += data;
                stats_item++;
                hw_reg_addr += 4;
        }
}

/**
 * atl1c_get_stats - Get System Network Statistics
 * @netdev: network interface device structure
 *
 * Returns the address of the device statistics structure.
 * The statistics are actually updated from the timer callback.
 */
static struct net_device_stats *atl1c_get_stats(struct net_device *netdev)
{
        struct atl1c_adapter *adapter = netdev_priv(netdev);
        struct atl1c_hw_stats  *hw_stats = &adapter->hw_stats;
        struct net_device_stats *net_stats = &netdev->stats;

        atl1c_update_hw_stats(adapter);
        net_stats->rx_bytes   = hw_stats->rx_byte_cnt;
        net_stats->tx_bytes   = hw_stats->tx_byte_cnt;
        net_stats->multicast  = hw_stats->rx_mcast;
        net_stats->collisions = hw_stats->tx_1_col +
                                hw_stats->tx_2_col +
                                hw_stats->tx_late_col +
                                hw_stats->tx_abort_col;

        net_stats->rx_errors  = hw_stats->rx_frag +
                                hw_stats->rx_fcs_err +
                                hw_stats->rx_len_err +
                                hw_stats->rx_sz_ov +
                                hw_stats->rx_rrd_ov +
                                hw_stats->rx_align_err +
                                hw_stats->rx_rxf_ov;

        net_stats->rx_fifo_errors   = hw_stats->rx_rxf_ov;
        net_stats->rx_length_errors = hw_stats->rx_len_err;
        net_stats->rx_crc_errors    = hw_stats->rx_fcs_err;
        net_stats->rx_frame_errors  = hw_stats->rx_align_err;
        net_stats->rx_dropped       = hw_stats->rx_rrd_ov;

        net_stats->tx_errors = hw_stats->tx_late_col +
                               hw_stats->tx_abort_col +
                               hw_stats->tx_underrun +
                               hw_stats->tx_trunc;

        net_stats->tx_fifo_errors    = hw_stats->tx_underrun;
        net_stats->tx_aborted_errors = hw_stats->tx_abort_col;
        net_stats->tx_window_errors  = hw_stats->tx_late_col;

        net_stats->rx_packets = hw_stats->rx_ok + net_stats->rx_errors;
        net_stats->tx_packets = hw_stats->tx_ok + net_stats->tx_errors;

        return net_stats;
}

static inline void atl1c_clear_phy_int(struct atl1c_adapter *adapter)
{
        u16 phy_data;

        spin_lock(&adapter->mdio_lock);
        atl1c_read_phy_reg(&adapter->hw, MII_ISR, &phy_data);
        spin_unlock(&adapter->mdio_lock);
}

static int atl1c_clean_tx(struct napi_struct *napi, int budget)
{
        struct atl1c_tpd_ring *tpd_ring =
                container_of(napi, struct atl1c_tpd_ring, napi);
        struct atl1c_adapter *adapter = tpd_ring->adapter;
        struct netdev_queue *txq =
                netdev_get_tx_queue(napi->dev, tpd_ring->num);
        struct atl1c_buffer *buffer_info;
        struct pci_dev *pdev = adapter->pdev;
        u16 next_to_clean = atomic_read(&tpd_ring->next_to_clean);
        u16 hw_next_to_clean;
        unsigned int total_bytes = 0, total_packets = 0;
        unsigned long flags;

        AT_READ_REGW(&adapter->hw, atl1c_qregs[tpd_ring->num].tpd_cons,
                     &hw_next_to_clean);

        while (next_to_clean != hw_next_to_clean) {
                buffer_info = &tpd_ring->buffer_info[next_to_clean];
                if (buffer_info->skb) {
                        total_bytes += buffer_info->skb->len;
                        total_packets++;
                }
                atl1c_clean_buffer(pdev, buffer_info, budget);
                if (++next_to_clean == tpd_ring->count)
                        next_to_clean = 0;
                atomic_set(&tpd_ring->next_to_clean, next_to_clean);
        }

        netdev_tx_completed_queue(txq, total_packets, total_bytes);

        if (netif_tx_queue_stopped(txq) && netif_carrier_ok(adapter->netdev))
                netif_tx_wake_queue(txq);

        if (total_packets < budget) {
                napi_complete_done(napi, total_packets);
                spin_lock_irqsave(&adapter->hw.intr_mask_lock, flags);
                adapter->hw.intr_mask |= atl1c_qregs[tpd_ring->num].tx_isr;
                AT_WRITE_REG(&adapter->hw, REG_IMR, adapter->hw.intr_mask);
                spin_unlock_irqrestore(&adapter->hw.intr_mask_lock, flags);
                return total_packets;
        }
        return budget;
}

static void atl1c_intr_rx_tx(struct atl1c_adapter *adapter, u32 status)
{
        struct atl1c_hw *hw = &adapter->hw;
        u32 intr_mask;
        int i;

        spin_lock(&hw->intr_mask_lock);
        intr_mask = hw->intr_mask;
        for (i = 0; i < adapter->rx_queue_count; ++i) {
                if (!(status & atl1c_qregs[i].rx_isr))
                        continue;
                if (napi_schedule_prep(&adapter->rrd_ring[i].napi)) {
                        intr_mask &= ~atl1c_qregs[i].rx_isr;
                        __napi_schedule(&adapter->rrd_ring[i].napi);
                }
        }
        for (i = 0; i < adapter->tx_queue_count; ++i) {
                if (!(status & atl1c_qregs[i].tx_isr))
                        continue;
                if (napi_schedule_prep(&adapter->tpd_ring[i].napi)) {
                        intr_mask &= ~atl1c_qregs[i].tx_isr;
                        __napi_schedule(&adapter->tpd_ring[i].napi);
                }
        }

        if (hw->intr_mask != intr_mask) {
                hw->intr_mask = intr_mask;
                AT_WRITE_REG(hw, REG_IMR, hw->intr_mask);
        }
        spin_unlock(&hw->intr_mask_lock);
}

/**
 * atl1c_intr - Interrupt Handler
 * @irq: interrupt number
 * @data: pointer to a network interface device structure
 */
static irqreturn_t atl1c_intr(int irq, void *data)
{
        struct net_device *netdev  = data;
        struct atl1c_adapter *adapter = netdev_priv(netdev);
        struct pci_dev *pdev = adapter->pdev;
        struct atl1c_hw *hw = &adapter->hw;
        int max_ints = AT_MAX_INT_WORK;
        int handled = IRQ_NONE;
        u32 status;
        u32 reg_data;

        do {
                AT_READ_REG(hw, REG_ISR, &reg_data);
                status = reg_data & hw->intr_mask;

                if (status == 0 || (status & ISR_DIS_INT) != 0) {
                        if (max_ints != AT_MAX_INT_WORK)
                                handled = IRQ_HANDLED;
                        break;
                }
                /* link event */
                if (status & ISR_GPHY)
                        atl1c_clear_phy_int(adapter);
                /* Ack ISR */
                AT_WRITE_REG(hw, REG_ISR, status | ISR_DIS_INT);
                if (status & (ISR_RX_PKT | ISR_TX_PKT))
                        atl1c_intr_rx_tx(adapter, status);

                handled = IRQ_HANDLED;
                /* check if PCIE PHY Link down */
                if (status & ISR_ERROR) {
                        if (netif_msg_hw(adapter))
                                dev_err(&pdev->dev,
                                        "atl1c hardware error (status = 0x%x)\n",
                                        status & ISR_ERROR);
                        /* reset MAC */
                        set_bit(ATL1C_WORK_EVENT_RESET, &adapter->work_event);
                        schedule_work(&adapter->common_task);
                        return IRQ_HANDLED;
                }

                if (status & ISR_OVER)
                        if (netif_msg_intr(adapter))
                                dev_warn(&pdev->dev,
                                        "TX/RX overflow (status = 0x%x)\n",
                                        status & ISR_OVER);

                /* link event */
                if (status & (ISR_GPHY | ISR_MANUAL)) {
                        netdev->stats.tx_carrier_errors++;
                        atl1c_link_chg_event(adapter);
                        break;
                }

        } while (--max_ints > 0);
        /* re-enable Interrupt*/
        AT_WRITE_REG(&adapter->hw, REG_ISR, 0);
        return handled;
}

static inline void atl1c_rx_checksum(struct atl1c_adapter *adapter,
                  struct sk_buff *skb, struct atl1c_recv_ret_status *prrs)
{
        if (adapter->hw.nic_type == athr_mt) {
                if (prrs->word3 & RRS_MT_PROT_ID_TCPUDP)
                        skb->ip_summed = CHECKSUM_UNNECESSARY;
                return;
        }
        /*
         * The pid field in RRS in not correct sometimes, so we
         * cannot figure out if the packet is fragmented or not,
         * so we tell the KERNEL CHECKSUM_NONE
         */
        skb_checksum_none_assert(skb);
}

static int atl1c_alloc_rx_buffer(struct atl1c_adapter *adapter, u32 queue,
                                 bool napi_mode)
{
        struct atl1c_rfd_ring *rfd_ring = &adapter->rfd_ring[queue];
        struct atl1c_rrd_ring *rrd_ring = &adapter->rrd_ring[queue];
        struct pci_dev *pdev = adapter->pdev;
        struct atl1c_buffer *buffer_info, *next_info;
        struct sk_buff *skb;
        void *vir_addr = NULL;
        u16 num_alloc = 0;
        u16 rfd_next_to_use, next_next;
        struct atl1c_rx_free_desc *rfd_desc;
        dma_addr_t mapping;

        next_next = rfd_next_to_use = rfd_ring->next_to_use;
        if (++next_next == rfd_ring->count)
                next_next = 0;
        buffer_info = &rfd_ring->buffer_info[rfd_next_to_use];
        next_info = &rfd_ring->buffer_info[next_next];

        while (next_info->flags & ATL1C_BUFFER_FREE) {
                rfd_desc = ATL1C_RFD_DESC(rfd_ring, rfd_next_to_use);

                /* When DMA RX address is set to something like
                 * 0x....fc0, it will be very likely to cause DMA
                 * RFD overflow issue.
                 *
                 * To work around it, we apply rx skb with 64 bytes
                 * longer space, and offset the address whenever
                 * 0x....fc0 is detected.
                 */
                if (likely(napi_mode))
                        skb = napi_alloc_skb(&rrd_ring->napi, adapter->rx_buffer_len + 64);
                else
                        skb = netdev_alloc_skb(adapter->netdev, adapter->rx_buffer_len + 64);
                if (unlikely(!skb)) {
                        if (netif_msg_rx_err(adapter))
                                dev_warn(&pdev->dev, "alloc rx buffer failed\n");
                        break;
                }

                if (((unsigned long)skb->data & 0xfff) == 0xfc0)
                        skb_reserve(skb, 64);

                /*
                 * Make buffer alignment 2 beyond a 16 byte boundary
                 * this will result in a 16 byte aligned IP header after
                 * the 14 byte MAC header is removed
                 */
                vir_addr = skb->data;
                ATL1C_SET_BUFFER_STATE(buffer_info, ATL1C_BUFFER_BUSY);
                buffer_info->skb = skb;
                buffer_info->length = adapter->rx_buffer_len;
                mapping = dma_map_single(&pdev->dev, vir_addr,
                                         buffer_info->length, DMA_FROM_DEVICE);
                if (unlikely(dma_mapping_error(&pdev->dev, mapping))) {
                        dev_kfree_skb(skb);
                        buffer_info->skb = NULL;
                        buffer_info->length = 0;
                        ATL1C_SET_BUFFER_STATE(buffer_info, ATL1C_BUFFER_FREE);
                        netif_warn(adapter, rx_err, adapter->netdev, "RX dma_map_single failed");
                        break;
                }
                buffer_info->dma = mapping;
                ATL1C_SET_PCIMAP_TYPE(buffer_info, ATL1C_PCIMAP_SINGLE,
                        ATL1C_PCIMAP_FROMDEVICE);
                rfd_desc->buffer_addr = cpu_to_le64(buffer_info->dma);
                rfd_next_to_use = next_next;
                if (++next_next == rfd_ring->count)
                        next_next = 0;
                buffer_info = &rfd_ring->buffer_info[rfd_next_to_use];
                next_info = &rfd_ring->buffer_info[next_next];
                num_alloc++;
        }

        if (num_alloc) {
                /* TODO: update mailbox here */
                wmb();
                rfd_ring->next_to_use = rfd_next_to_use;
                AT_WRITE_REG(&adapter->hw, atl1c_qregs[queue].rfd_prod,
                             rfd_ring->next_to_use & MB_RFDX_PROD_IDX_MASK);
        }

        return num_alloc;
}

static void atl1c_clean_rrd(struct atl1c_rrd_ring *rrd_ring,
                        struct  atl1c_recv_ret_status *rrs, u16 num)
{
        u16 i;
        /* the relationship between rrd and rfd is one map one */
        for (i = 0; i < num; i++, rrs = ATL1C_RRD_DESC(rrd_ring,
                                        rrd_ring->next_to_clean)) {
                rrs->word3 &= ~RRS_RXD_UPDATED;
                if (++rrd_ring->next_to_clean == rrd_ring->count)
                        rrd_ring->next_to_clean = 0;
        }
}

static void atl1c_clean_rfd(struct atl1c_rfd_ring *rfd_ring,
        struct atl1c_recv_ret_status *rrs, u16 num)
{
        u16 i;
        u16 rfd_index;
        struct atl1c_buffer *buffer_info = rfd_ring->buffer_info;

        rfd_index = (rrs->word0 >> RRS_RX_RFD_INDEX_SHIFT) &
                        RRS_RX_RFD_INDEX_MASK;
        for (i = 0; i < num; i++) {
                buffer_info[rfd_index].skb = NULL;
                ATL1C_SET_BUFFER_STATE(&buffer_info[rfd_index],
                                        ATL1C_BUFFER_FREE);
                if (++rfd_index == rfd_ring->count)
                        rfd_index = 0;
        }
        rfd_ring->next_to_clean = rfd_index;
}

/**
 * atl1c_clean_rx - NAPI Rx polling callback
 * @napi: napi info
 * @budget: limit of packets to clean
 */
static int atl1c_clean_rx(struct napi_struct *napi, int budget)
{
        struct atl1c_rrd_ring *rrd_ring =
                container_of(napi, struct atl1c_rrd_ring, napi);
        struct atl1c_adapter *adapter = rrd_ring->adapter;
        u16 rfd_num, rfd_index;
        u16 length;
        struct pci_dev *pdev = adapter->pdev;
        struct net_device *netdev  = adapter->netdev;
        struct atl1c_rfd_ring *rfd_ring = &adapter->rfd_ring[rrd_ring->num];
        struct sk_buff *skb;
        struct atl1c_recv_ret_status *rrs;
        struct atl1c_buffer *buffer_info;
        int work_done = 0;
        unsigned long flags;

        /* Keep link state information with original netdev */
        if (!netif_carrier_ok(adapter->netdev))
                goto quit_polling;

        while (1) {
                if (work_done >= budget)
                        break;
                rrs = ATL1C_RRD_DESC(rrd_ring, rrd_ring->next_to_clean);
                if (likely(RRS_RXD_IS_VALID(rrs->word3))) {
                        rfd_num = (rrs->word0 >> RRS_RX_RFD_CNT_SHIFT) &
                                RRS_RX_RFD_CNT_MASK;
                        if (unlikely(rfd_num != 1))
                                /* TODO support mul rfd*/
                                if (netif_msg_rx_err(adapter))
                                        dev_warn(&pdev->dev,
                                                "Multi rfd not support yet!\n");
                        goto rrs_checked;
                } else {
                        break;
                }
rrs_checked:
                atl1c_clean_rrd(rrd_ring, rrs, rfd_num);
                if (rrs->word3 & (RRS_RX_ERR_SUM | RRS_802_3_LEN_ERR)) {
                        atl1c_clean_rfd(rfd_ring, rrs, rfd_num);
                        if (netif_msg_rx_err(adapter))
                                dev_warn(&pdev->dev,
                                         "wrong packet! rrs word3 is %x\n",
                                         rrs->word3);
                        continue;
                }

                length = le16_to_cpu((rrs->word3 >> RRS_PKT_SIZE_SHIFT) &
                                RRS_PKT_SIZE_MASK);
                /* Good Receive */
                if (likely(rfd_num == 1)) {
                        rfd_index = (rrs->word0 >> RRS_RX_RFD_INDEX_SHIFT) &
                                        RRS_RX_RFD_INDEX_MASK;
                        buffer_info = &rfd_ring->buffer_info[rfd_index];
                        dma_unmap_single(&pdev->dev, buffer_info->dma,
                                         buffer_info->length, DMA_FROM_DEVICE);
                        skb = buffer_info->skb;
                } else {
                        /* TODO */
                        if (netif_msg_rx_err(adapter))
                                dev_warn(&pdev->dev,
                                        "Multi rfd not support yet!\n");
                        break;
                }
                atl1c_clean_rfd(rfd_ring, rrs, rfd_num);
                skb_put(skb, length - ETH_FCS_LEN);
                skb->protocol = eth_type_trans(skb, netdev);
                atl1c_rx_checksum(adapter, skb, rrs);
                if (rrs->word3 & RRS_VLAN_INS) {
                        u16 vlan;

                        AT_TAG_TO_VLAN(rrs->vlan_tag, vlan);
                        vlan = le16_to_cpu(vlan);
                        __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), vlan);
                }
                napi_gro_receive(napi, skb);

                work_done++;
        }
        if (work_done)
                atl1c_alloc_rx_buffer(adapter, rrd_ring->num, true);

        if (work_done < budget) {
quit_polling:
                napi_complete_done(napi, work_done);
                spin_lock_irqsave(&adapter->hw.intr_mask_lock, flags);
                adapter->hw.intr_mask |= atl1c_qregs[rrd_ring->num].rx_isr;
                AT_WRITE_REG(&adapter->hw, REG_IMR, adapter->hw.intr_mask);
                spin_unlock_irqrestore(&adapter->hw.intr_mask_lock, flags);
        }
        return work_done;
}

#ifdef CONFIG_NET_POLL_CONTROLLER

/*
 * Polling 'interrupt' - used by things like netconsole to send skbs
 * without having to re-enable interrupts. It's not called while
 * the interrupt routine is executing.
 */
static void atl1c_netpoll(struct net_device *netdev)
{
        struct atl1c_adapter *adapter = netdev_priv(netdev);

        disable_irq(adapter->pdev->irq);
        atl1c_intr(adapter->pdev->irq, netdev);
        enable_irq(adapter->pdev->irq);
}
#endif

static inline u16 atl1c_tpd_avail(struct atl1c_adapter *adapter, u32 queue)
{
        struct atl1c_tpd_ring *tpd_ring = &adapter->tpd_ring[queue];
        u16 next_to_use = 0;
        u16 next_to_clean = 0;

        next_to_clean = atomic_read(&tpd_ring->next_to_clean);
        next_to_use   = tpd_ring->next_to_use;

        return (u16)(next_to_clean > next_to_use) ?
                (next_to_clean - next_to_use - 1) :
                (tpd_ring->count + next_to_clean - next_to_use - 1);
}

/*
 * get next usable tpd
 * Note: should call atl1c_tdp_avail to make sure
 * there is enough tpd to use
 */
static struct atl1c_tpd_desc *atl1c_get_tpd(struct atl1c_adapter *adapter,
                                            u32 queue)
{
        struct atl1c_tpd_ring *tpd_ring = &adapter->tpd_ring[queue];
        struct atl1c_tpd_desc *tpd_desc;
        u16 next_to_use = 0;

        next_to_use = tpd_ring->next_to_use;
        if (++tpd_ring->next_to_use == tpd_ring->count)
                tpd_ring->next_to_use = 0;
        tpd_desc = ATL1C_TPD_DESC(tpd_ring, next_to_use);
        memset(tpd_desc, 0, sizeof(struct atl1c_tpd_desc));
        return  tpd_desc;
}

static struct atl1c_buffer *
atl1c_get_tx_buffer(struct atl1c_adapter *adapter, struct atl1c_tpd_desc *tpd)
{
        struct atl1c_tpd_ring *tpd_ring = adapter->tpd_ring;

        return &tpd_ring->buffer_info[tpd -
                        (struct atl1c_tpd_desc *)tpd_ring->desc];
}

/* Calculate the transmit packet descript needed*/
static u16 atl1c_cal_tpd_req(const struct sk_buff *skb)
{
        u16 tpd_req;
        u16 proto_hdr_len = 0;

        tpd_req = skb_shinfo(skb)->nr_frags + 1;

        if (skb_is_gso(skb)) {
                proto_hdr_len = skb_tcp_all_headers(skb);
                if (proto_hdr_len < skb_headlen(skb))
                        tpd_req++;
                if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6)
                        tpd_req++;
        }
        return tpd_req;
}

static int atl1c_tso_csum(struct atl1c_adapter *adapter,
                          struct sk_buff *skb,
                          struct atl1c_tpd_desc **tpd,
                          u32 queue)
{
        struct pci_dev *pdev = adapter->pdev;
        unsigned short offload_type;
        u8 hdr_len;
        u32 real_len;

        if (skb_is_gso(skb)) {
                int err;

                err = skb_cow_head(skb, 0);
                if (err < 0)
                        return err;

                offload_type = skb_shinfo(skb)->gso_type;

                if (offload_type & SKB_GSO_TCPV4) {
                        real_len = (((unsigned char *)ip_hdr(skb) - skb->data)
                                        + ntohs(ip_hdr(skb)->tot_len));

                        if (real_len < skb->len) {
                                err = pskb_trim(skb, real_len);
                                if (err)
                                        return err;
                        }

                        hdr_len = skb_tcp_all_headers(skb);
                        if (unlikely(skb->len == hdr_len)) {
                                /* only xsum need */
                                if (netif_msg_tx_queued(adapter))
                                        dev_warn(&pdev->dev,
                                                "IPV4 tso with zero data??\n");
                                goto check_sum;
                        } else {
                                ip_hdr(skb)->check = 0;
                                tcp_hdr(skb)->check = ~csum_tcpudp_magic(
                                                        ip_hdr(skb)->saddr,
                                                        ip_hdr(skb)->daddr,
                                                        0, IPPROTO_TCP, 0);
                                (*tpd)->word1 |= 1 << TPD_IPV4_PACKET_SHIFT;
                        }
                }

                if (offload_type & SKB_GSO_TCPV6) {
                        struct atl1c_tpd_ext_desc *etpd =
                                *(struct atl1c_tpd_ext_desc **)(tpd);

                        memset(etpd, 0, sizeof(struct atl1c_tpd_ext_desc));
                        *tpd = atl1c_get_tpd(adapter, queue);
                        ipv6_hdr(skb)->payload_len = 0;
                        /* check payload == 0 byte ? */
                        hdr_len = skb_tcp_all_headers(skb);
                        if (unlikely(skb->len == hdr_len)) {
                                /* only xsum need */
                                if (netif_msg_tx_queued(adapter))
                                        dev_warn(&pdev->dev,
                                                "IPV6 tso with zero data??\n");
                                goto check_sum;
                        } else
                                tcp_v6_gso_csum_prep(skb);

                        etpd->word1 |= 1 << TPD_LSO_EN_SHIFT;
                        etpd->word1 |= 1 << TPD_LSO_VER_SHIFT;
                        etpd->pkt_len = cpu_to_le32(skb->len);
                        (*tpd)->word1 |= 1 << TPD_LSO_VER_SHIFT;
                }

                (*tpd)->word1 |= 1 << TPD_LSO_EN_SHIFT;
                (*tpd)->word1 |= (skb_transport_offset(skb) & TPD_TCPHDR_OFFSET_MASK) <<
                                TPD_TCPHDR_OFFSET_SHIFT;
                (*tpd)->word1 |= (skb_shinfo(skb)->gso_size & TPD_MSS_MASK) <<
                                TPD_MSS_SHIFT;
                return 0;
        }

check_sum:
        if (likely(skb->ip_summed == CHECKSUM_PARTIAL)) {
                u8 css, cso;
                cso = skb_checksum_start_offset(skb);

                if (unlikely(cso & 0x1)) {
                        if (netif_msg_tx_err(adapter))
                                dev_err(&adapter->pdev->dev,
                                        "payload offset should not an event number\n");
                        return -1;
                } else {
                        css = cso + skb->csum_offset;

                        (*tpd)->word1 |= ((cso >> 1) & TPD_PLOADOFFSET_MASK) <<
                                        TPD_PLOADOFFSET_SHIFT;
                        (*tpd)->word1 |= ((css >> 1) & TPD_CCSUM_OFFSET_MASK) <<
                                        TPD_CCSUM_OFFSET_SHIFT;
                        (*tpd)->word1 |= 1 << TPD_CCSUM_EN_SHIFT;
                }
        }
        return 0;
}

static void atl1c_tx_rollback(struct atl1c_adapter *adpt,
                              struct atl1c_tpd_desc *first_tpd,
                              u32 queue)
{
        struct atl1c_tpd_ring *tpd_ring = &adpt->tpd_ring[queue];
        struct atl1c_buffer *buffer_info;
        struct atl1c_tpd_desc *tpd;
        u16 first_index, index;

        first_index = first_tpd - (struct atl1c_tpd_desc *)tpd_ring->desc;
        index = first_index;
        while (index != tpd_ring->next_to_use) {
                tpd = ATL1C_TPD_DESC(tpd_ring, index);
                buffer_info = &tpd_ring->buffer_info[index];
                atl1c_clean_buffer(adpt->pdev, buffer_info, 0);
                memset(tpd, 0, sizeof(struct atl1c_tpd_desc));
                if (++index == tpd_ring->count)
                        index = 0;
        }
        tpd_ring->next_to_use = first_index;
}

static int atl1c_tx_map(struct atl1c_adapter *adapter,
                        struct sk_buff *skb, struct atl1c_tpd_desc *tpd,
                        u32 queue)
{
        struct atl1c_tpd_desc *use_tpd = NULL;
        struct atl1c_buffer *buffer_info = NULL;
        u16 buf_len = skb_headlen(skb);
        u16 map_len = 0;
        u16 mapped_len = 0;
        u16 hdr_len = 0;
        u16 nr_frags;
        u16 f;
        int tso;

        nr_frags = skb_shinfo(skb)->nr_frags;
        tso = (tpd->word1 >> TPD_LSO_EN_SHIFT) & TPD_LSO_EN_MASK;
        if (tso) {
                /* TSO */
                hdr_len = skb_tcp_all_headers(skb);
                map_len = hdr_len;
                use_tpd = tpd;

                buffer_info = atl1c_get_tx_buffer(adapter, use_tpd);
                buffer_info->length = map_len;
                buffer_info->dma = dma_map_single(&adapter->pdev->dev,
                                                  skb->data, hdr_len,
                                                  DMA_TO_DEVICE);
                if (unlikely(dma_mapping_error(&adapter->pdev->dev, buffer_info->dma)))
                        goto err_dma;
                ATL1C_SET_BUFFER_STATE(buffer_info, ATL1C_BUFFER_BUSY);
                ATL1C_SET_PCIMAP_TYPE(buffer_info, ATL1C_PCIMAP_SINGLE,
                        ATL1C_PCIMAP_TODEVICE);
                mapped_len += map_len;
                use_tpd->buffer_addr = cpu_to_le64(buffer_info->dma);
                use_tpd->buffer_len = cpu_to_le16(buffer_info->length);
        }

        if (mapped_len < buf_len) {
                /* mapped_len == 0, means we should use the first tpd,
                   which is given by caller  */
                if (mapped_len == 0)
                        use_tpd = tpd;
                else {
                        use_tpd = atl1c_get_tpd(adapter, queue);
                        memcpy(use_tpd, tpd, sizeof(struct atl1c_tpd_desc));
                }
                buffer_info = atl1c_get_tx_buffer(adapter, use_tpd);
                buffer_info->length = buf_len - mapped_len;
                buffer_info->dma =
                        dma_map_single(&adapter->pdev->dev,
                                       skb->data + mapped_len,
                                       buffer_info->length, DMA_TO_DEVICE);
                if (unlikely(dma_mapping_error(&adapter->pdev->dev, buffer_info->dma)))
                        goto err_dma;

                ATL1C_SET_BUFFER_STATE(buffer_info, ATL1C_BUFFER_BUSY);
                ATL1C_SET_PCIMAP_TYPE(buffer_info, ATL1C_PCIMAP_SINGLE,
                        ATL1C_PCIMAP_TODEVICE);
                use_tpd->buffer_addr = cpu_to_le64(buffer_info->dma);
                use_tpd->buffer_len  = cpu_to_le16(buffer_info->length);
        }

        for (f = 0; f < nr_frags; f++) {
                skb_frag_t *frag = &skb_shinfo(skb)->frags[f];

                use_tpd = atl1c_get_tpd(adapter, queue);
                memcpy(use_tpd, tpd, sizeof(struct atl1c_tpd_desc));

                buffer_info = atl1c_get_tx_buffer(adapter, use_tpd);
                buffer_info->length = skb_frag_size(frag);
                buffer_info->dma = skb_frag_dma_map(&adapter->pdev->dev,
                                                    frag, 0,
                                                    buffer_info->length,
                                                    DMA_TO_DEVICE);
                if (dma_mapping_error(&adapter->pdev->dev, buffer_info->dma))
                        goto err_dma;

                ATL1C_SET_BUFFER_STATE(buffer_info, ATL1C_BUFFER_BUSY);
                ATL1C_SET_PCIMAP_TYPE(buffer_info, ATL1C_PCIMAP_PAGE,
                        ATL1C_PCIMAP_TODEVICE);
                use_tpd->buffer_addr = cpu_to_le64(buffer_info->dma);
                use_tpd->buffer_len  = cpu_to_le16(buffer_info->length);
        }

        /* The last tpd */
        use_tpd->word1 |= 1 << TPD_EOP_SHIFT;
        /* The last buffer info contain the skb address,
           so it will be free after unmap */
        buffer_info->skb = skb;

        return 0;

err_dma:
        buffer_info->dma = 0;
        buffer_info->length = 0;
        return -1;
}

static void atl1c_tx_queue(struct atl1c_adapter *adapter, u32 queue)
{
        struct atl1c_tpd_ring *tpd_ring = &adapter->tpd_ring[queue];

        AT_WRITE_REGW(&adapter->hw, atl1c_qregs[queue].tpd_prod,
                      tpd_ring->next_to_use);
}

static netdev_tx_t atl1c_xmit_frame(struct sk_buff *skb,
                                          struct net_device *netdev)
{
        struct atl1c_adapter *adapter = netdev_priv(netdev);
        u32 queue = skb_get_queue_mapping(skb);
        struct netdev_queue *txq = netdev_get_tx_queue(netdev, queue);
        struct atl1c_tpd_desc *tpd;
        u16 tpd_req;

        if (test_bit(__AT_DOWN, &adapter->flags)) {
                dev_kfree_skb_any(skb);
                return NETDEV_TX_OK;
        }

        tpd_req = atl1c_cal_tpd_req(skb);

        if (atl1c_tpd_avail(adapter, queue) < tpd_req) {
                /* no enough descriptor, just stop queue */
                atl1c_tx_queue(adapter, queue);
                netif_tx_stop_queue(txq);
                return NETDEV_TX_BUSY;
        }

        tpd = atl1c_get_tpd(adapter, queue);

        /* do TSO and check sum */
        if (atl1c_tso_csum(adapter, skb, &tpd, queue) != 0) {
                atl1c_tx_queue(adapter, queue);
                dev_kfree_skb_any(skb);
                return NETDEV_TX_OK;
        }

        if (unlikely(skb_vlan_tag_present(skb))) {
                u16 vlan = skb_vlan_tag_get(skb);
                __le16 tag;

                vlan = cpu_to_le16(vlan);
                AT_VLAN_TO_TAG(vlan, tag);
                tpd->word1 |= 1 << TPD_INS_VTAG_SHIFT;
                tpd->vlan_tag = tag;
        }

        if (skb_network_offset(skb) != ETH_HLEN)
                tpd->word1 |= 1 << TPD_ETH_TYPE_SHIFT; /* Ethernet frame */

        if (atl1c_tx_map(adapter, skb, tpd, queue) < 0) {
                netif_info(adapter, tx_done, adapter->netdev,
                           "tx-skb dropped due to dma error\n");
                /* roll back tpd/buffer */
                atl1c_tx_rollback(adapter, tpd, queue);
                dev_kfree_skb_any(skb);
        } else {
                bool more = netdev_xmit_more();

                if (__netdev_tx_sent_queue(txq, skb->len, more))
                        atl1c_tx_queue(adapter, queue);
        }

        return NETDEV_TX_OK;
}

static void atl1c_free_irq(struct atl1c_adapter *adapter)
{
        struct net_device *netdev = adapter->netdev;

        free_irq(adapter->pdev->irq, netdev);

        if (adapter->have_msi)
                pci_disable_msi(adapter->pdev);
}

static int atl1c_request_irq(struct atl1c_adapter *adapter)
{
        struct pci_dev    *pdev   = adapter->pdev;
        struct net_device *netdev = adapter->netdev;
        int flags = 0;
        int err = 0;

        adapter->have_msi = true;
        err = pci_enable_msi(adapter->pdev);
        if (err) {
                if (netif_msg_ifup(adapter))
                        dev_err(&pdev->dev,
                                "Unable to allocate MSI interrupt Error: %d\n",
                                err);
                adapter->have_msi = false;
        }

        if (!adapter->have_msi)
                flags |= IRQF_SHARED;
        err = request_irq(adapter->pdev->irq, atl1c_intr, flags,
                        netdev->name, netdev);
        if (err) {
                if (netif_msg_ifup(adapter))
                        dev_err(&pdev->dev,
                                "Unable to allocate interrupt Error: %d\n",
                                err);
                if (adapter->have_msi)
                        pci_disable_msi(adapter->pdev);
                return err;
        }
        if (netif_msg_ifup(adapter))
                dev_dbg(&pdev->dev, "atl1c_request_irq OK\n");
        return err;
}


static void atl1c_reset_dma_ring(struct atl1c_adapter *adapter)
{
        int i;
        /* release tx-pending skbs and reset tx/rx ring index */
        for (i = 0; i < adapter->tx_queue_count; ++i)
                atl1c_clean_tx_ring(adapter, i);
        for (i = 0; i < adapter->rx_queue_count; ++i)
                atl1c_clean_rx_ring(adapter, i);
}

static int atl1c_up(struct atl1c_adapter *adapter)
{
        struct net_device *netdev = adapter->netdev;
        int err;
        int i;

        netif_carrier_off(netdev);

        err = atl1c_configure(adapter);
        if (unlikely(err))
                goto err_up;

        err = atl1c_request_irq(adapter);
        if (unlikely(err))
                goto err_up;

        atl1c_check_link_status(adapter);
        clear_bit(__AT_DOWN, &adapter->flags);
        for (i = 0; i < adapter->tx_queue_count; ++i)
                napi_enable(&adapter->tpd_ring[i].napi);
        for (i = 0; i < adapter->rx_queue_count; ++i)
                napi_enable(&adapter->rrd_ring[i].napi);
        atl1c_irq_enable(adapter);
        netif_start_queue(netdev);
        return err;

err_up:
        for (i = 0; i < adapter->rx_queue_count; ++i)
                atl1c_clean_rx_ring(adapter, i);
        return err;
}

static void atl1c_down(struct atl1c_adapter *adapter)
{
        struct net_device *netdev = adapter->netdev;
        int i;

        atl1c_del_timer(adapter);
        adapter->work_event = 0; /* clear all event */
        /* signal that we're down so the interrupt handler does not
         * reschedule our watchdog timer */
        set_bit(__AT_DOWN, &adapter->flags);
        netif_carrier_off(netdev);
        for (i = 0; i < adapter->tx_queue_count; ++i)
                napi_disable(&adapter->tpd_ring[i].napi);
        for (i = 0; i < adapter->rx_queue_count; ++i)
                napi_disable(&adapter->rrd_ring[i].napi);
        atl1c_irq_disable(adapter);
        atl1c_free_irq(adapter);
        /* disable ASPM if device inactive */
        atl1c_disable_l0s_l1(&adapter->hw);
        /* reset MAC to disable all RX/TX */
        atl1c_reset_mac(&adapter->hw);
        msleep(1);

        adapter->link_speed = SPEED_0;
        adapter->link_duplex = -1;
        atl1c_reset_dma_ring(adapter);
}

/**
 * atl1c_open - Called when a network interface is made active
 * @netdev: network interface device structure
 *
 * Returns 0 on success, negative value on failure
 *
 * The open entry point is called when a network interface is made
 * active by the system (IFF_UP).  At this point all resources needed
 * for transmit and receive operations are allocated, the interrupt
 * handler is registered with the OS, the watchdog timer is started,
 * and the stack is notified that the interface is ready.
 */
static int atl1c_open(struct net_device *netdev)
{
        struct atl1c_adapter *adapter = netdev_priv(netdev);
        int err;

        /* disallow open during test */
        if (test_bit(__AT_TESTING, &adapter->flags))
                return -EBUSY;

        /* allocate rx/tx dma buffer & descriptors */
        err = atl1c_setup_ring_resources(adapter);
        if (unlikely(err))
                return err;

        err = atl1c_up(adapter);
        if (unlikely(err))
                goto err_up;

        return 0;

err_up:
        atl1c_free_irq(adapter);
        atl1c_free_ring_resources(adapter);
        atl1c_reset_mac(&adapter->hw);
        return err;
}

/**
 * atl1c_close - Disables a network interface
 * @netdev: network interface device structure
 *
 * Returns 0, this is not allowed to fail
 *
 * The close entry point is called when an interface is de-activated
 * by the OS.  The hardware is still under the drivers control, but
 * needs to be disabled.  A global MAC reset is issued to stop the
 * hardware, and all transmit and receive resources are freed.
 */
static int atl1c_close(struct net_device *netdev)
{
        struct atl1c_adapter *adapter = netdev_priv(netdev);

        WARN_ON(test_bit(__AT_RESETTING, &adapter->flags));
        set_bit(__AT_DOWN, &adapter->flags);
        cancel_work_sync(&adapter->common_task);
        atl1c_down(adapter);
        atl1c_free_ring_resources(adapter);
        return 0;
}

static int atl1c_suspend(struct device *dev)
{
        struct net_device *netdev = dev_get_drvdata(dev);
        struct atl1c_adapter *adapter = netdev_priv(netdev);
        struct atl1c_hw *hw = &adapter->hw;
        u32 wufc = adapter->wol;

        atl1c_disable_l0s_l1(hw);
        if (netif_running(netdev)) {
                WARN_ON(test_bit(__AT_RESETTING, &adapter->flags));
                atl1c_down(adapter);
        }
        netif_device_detach(netdev);

        if (wufc)
                if (atl1c_phy_to_ps_link(hw) != 0)
                        dev_dbg(dev, "phy power saving failed");

        atl1c_power_saving(hw, wufc);

        return 0;
}

#ifdef CONFIG_PM_SLEEP
static int atl1c_resume(struct device *dev)
{
        struct net_device *netdev = dev_get_drvdata(dev);
        struct atl1c_adapter *adapter = netdev_priv(netdev);

        AT_WRITE_REG(&adapter->hw, REG_WOL_CTRL, 0);
        atl1c_reset_pcie(&adapter->hw, ATL1C_PCIE_L0S_L1_DISABLE);

        atl1c_phy_reset(&adapter->hw);
        atl1c_reset_mac(&adapter->hw);
        atl1c_phy_init(&adapter->hw);

        netif_device_attach(netdev);
        if (netif_running(netdev))
                atl1c_up(adapter);

        return 0;
}
#endif

static void atl1c_shutdown(struct pci_dev *pdev)
{
        struct net_device *netdev = pci_get_drvdata(pdev);
        struct atl1c_adapter *adapter = netdev_priv(netdev);

        atl1c_suspend(&pdev->dev);
        pci_wake_from_d3(pdev, adapter->wol);
        pci_set_power_state(pdev, PCI_D3hot);
}

static const struct net_device_ops atl1c_netdev_ops = {
        .ndo_open               = atl1c_open,
        .ndo_stop               = atl1c_close,
        .ndo_validate_addr      = eth_validate_addr,
        .ndo_start_xmit         = atl1c_xmit_frame,
        .ndo_set_mac_address    = atl1c_set_mac_addr,
        .ndo_set_rx_mode        = atl1c_set_multi,
        .ndo_change_mtu         = atl1c_change_mtu,
        .ndo_fix_features       = atl1c_fix_features,
        .ndo_set_features       = atl1c_set_features,
        .ndo_eth_ioctl          = atl1c_ioctl,
        .ndo_tx_timeout         = atl1c_tx_timeout,
        .ndo_get_stats          = atl1c_get_stats,
#ifdef CONFIG_NET_POLL_CONTROLLER
        .ndo_poll_controller    = atl1c_netpoll,
#endif
};

static int atl1c_init_netdev(struct net_device *netdev, struct pci_dev *pdev)
{
        SET_NETDEV_DEV(netdev, &pdev->dev);
        pci_set_drvdata(pdev, netdev);

        netdev->netdev_ops = &atl1c_netdev_ops;
        netdev->watchdog_timeo = AT_TX_WATCHDOG;
        netdev->min_mtu = ETH_ZLEN - (ETH_HLEN + VLAN_HLEN);
        atl1c_set_ethtool_ops(netdev);

        /* TODO: add when ready */
        netdev->hw_features =   NETIF_F_SG              |
                                NETIF_F_HW_CSUM         |
                                NETIF_F_HW_VLAN_CTAG_RX |
                                NETIF_F_TSO             |
                                NETIF_F_TSO6;
        netdev->features =      netdev->hw_features     |
                                NETIF_F_HW_VLAN_CTAG_TX;
        return 0;
}

/**
 * atl1c_probe - Device Initialization Routine
 * @pdev: PCI device information struct
 * @ent: entry in atl1c_pci_tbl
 *
 * Returns 0 on success, negative on failure
 *
 * atl1c_probe initializes an adapter identified by a pci_dev structure.
 * The OS initialization, configuring of the adapter private structure,
 * and a hardware reset occur.
 */
static int atl1c_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
{
        struct net_device *netdev;
        struct atl1c_adapter *adapter;
        static int cards_found;
        u8 __iomem *hw_addr;
        enum atl1c_nic_type nic_type;
        u32 queue_count = 1;
        int err = 0;
        int i;

        /* enable device (incl. PCI PM wakeup and hotplug setup) */
        err = pci_enable_device_mem(pdev);
        if (err)
                return dev_err_probe(&pdev->dev, err, "cannot enable PCI device\n");

        /*
         * The atl1c chip can DMA to 64-bit addresses, but it uses a single
         * shared register for the high 32 bits, so only a single, aligned,
         * 4 GB physical address range can be used at a time.
         *
         * Supporting 64-bit DMA on this hardware is more trouble than it's
         * worth.  It is far easier to limit to 32-bit DMA than update
         * various kernel subsystems to support the mechanics required by a
         * fixed-high-32-bit system.
         */
        err = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
        if (err) {
                dev_err(&pdev->dev, "No usable DMA configuration,aborting\n");
                goto err_dma;
        }

        err = pci_request_regions(pdev, atl1c_driver_name);
        if (err) {
                dev_err(&pdev->dev, "cannot obtain PCI resources\n");
                goto err_pci_reg;
        }

        pci_set_master(pdev);

        hw_addr = pci_ioremap_bar(pdev, 0);
        if (!hw_addr) {
                err = -EIO;
                dev_err(&pdev->dev, "cannot map device registers\n");
                goto err_ioremap;
        }

        nic_type = atl1c_get_mac_type(pdev, hw_addr);
        if (nic_type == athr_mt)
                queue_count = 4;

        netdev = alloc_etherdev_mq(sizeof(struct atl1c_adapter), queue_count);
        if (netdev == NULL) {
                err = -ENOMEM;
                goto err_alloc_etherdev;
        }

        err = atl1c_init_netdev(netdev, pdev);
        if (err) {
                dev_err(&pdev->dev, "init netdevice failed\n");
                goto err_init_netdev;
        }
        adapter = netdev_priv(netdev);
        adapter->bd_number = cards_found;
        adapter->netdev = netdev;
        adapter->pdev = pdev;
        adapter->hw.adapter = adapter;
        adapter->hw.nic_type = nic_type;
        adapter->msg_enable = netif_msg_init(-1, atl1c_default_msg);
        adapter->hw.hw_addr = hw_addr;
        adapter->tx_queue_count = queue_count;
        adapter->rx_queue_count = queue_count;

        /* init mii data */
        adapter->mii.dev = netdev;
        adapter->mii.mdio_read  = atl1c_mdio_read;
        adapter->mii.mdio_write = atl1c_mdio_write;
        adapter->mii.phy_id_mask = 0x1f;
        adapter->mii.reg_num_mask = MDIO_CTRL_REG_MASK;
        netif_threaded_enable(netdev);
        for (i = 0; i < adapter->rx_queue_count; ++i)
                netif_napi_add(netdev, &adapter->rrd_ring[i].napi,
                               atl1c_clean_rx);
        for (i = 0; i < adapter->tx_queue_count; ++i)
                netif_napi_add_tx(netdev, &adapter->tpd_ring[i].napi,
                                  atl1c_clean_tx);
        timer_setup(&adapter->phy_config_timer, atl1c_phy_config, 0);
        /* setup the private structure */
        err = atl1c_sw_init(adapter);
        if (err) {
                dev_err(&pdev->dev, "net device private data init failed\n");
                goto err_sw_init;
        }
        /* set max MTU */
        atl1c_set_max_mtu(netdev);

        atl1c_reset_pcie(&adapter->hw, ATL1C_PCIE_L0S_L1_DISABLE);

        /* Init GPHY as early as possible due to power saving issue  */
        atl1c_phy_reset(&adapter->hw);

        err = atl1c_reset_mac(&adapter->hw);
        if (err) {
                err = -EIO;
                goto err_reset;
        }

        /* reset the controller to
         * put the device in a known good starting state */
        err = atl1c_phy_init(&adapter->hw);
        if (err) {
                err = -EIO;
                goto err_reset;
        }
        if (atl1c_read_mac_addr(&adapter->hw)) {
                /* got a random MAC address, set NET_ADDR_RANDOM to netdev */
                netdev->addr_assign_type = NET_ADDR_RANDOM;
        }
        eth_hw_addr_set(netdev, adapter->hw.mac_addr);
        if (netif_msg_probe(adapter))
                dev_dbg(&pdev->dev, "mac address : %pM\n",
                        adapter->hw.mac_addr);

        atl1c_hw_set_mac_addr(&adapter->hw, adapter->hw.mac_addr);
        INIT_WORK(&adapter->common_task, atl1c_common_task);
        adapter->work_event = 0;
        err = register_netdev(netdev);
        if (err) {
                dev_err(&pdev->dev, "register netdevice failed\n");
                goto err_register;
        }

        cards_found++;
        return 0;

err_reset:
err_register:
err_sw_init:
err_init_netdev:
        free_netdev(netdev);
err_alloc_etherdev:
        iounmap(hw_addr);
err_ioremap:
        pci_release_regions(pdev);
err_pci_reg:
err_dma:
        pci_disable_device(pdev);
        return err;
}

/**
 * atl1c_remove - Device Removal Routine
 * @pdev: PCI device information struct
 *
 * atl1c_remove is called by the PCI subsystem to alert the driver
 * that it should release a PCI device.  The could be caused by a
 * Hot-Plug event, or because the driver is going to be removed from
 * memory.
 */
static void atl1c_remove(struct pci_dev *pdev)
{
        struct net_device *netdev = pci_get_drvdata(pdev);
        struct atl1c_adapter *adapter = netdev_priv(netdev);

        unregister_netdev(netdev);
        /* restore permanent address */
        atl1c_hw_set_mac_addr(&adapter->hw, adapter->hw.perm_mac_addr);
        atl1c_phy_disable(&adapter->hw);

        iounmap(adapter->hw.hw_addr);

        pci_release_regions(pdev);
        pci_disable_device(pdev);
        free_netdev(netdev);
}

/**
 * atl1c_io_error_detected - called when PCI error is detected
 * @pdev: Pointer to PCI device
 * @state: The current pci connection state
 *
 * This function is called after a PCI bus error affecting
 * this device has been detected.
 */
static pci_ers_result_t atl1c_io_error_detected(struct pci_dev *pdev,
                                                pci_channel_state_t state)
{
        struct net_device *netdev = pci_get_drvdata(pdev);
        struct atl1c_adapter *adapter = netdev_priv(netdev);

        netif_device_detach(netdev);

        if (state == pci_channel_io_perm_failure)
                return PCI_ERS_RESULT_DISCONNECT;

        if (netif_running(netdev))
                atl1c_down(adapter);

        pci_disable_device(pdev);

        /* Request a slot reset. */
        return PCI_ERS_RESULT_NEED_RESET;
}

/**
 * atl1c_io_slot_reset - called after the pci bus has been reset.
 * @pdev: Pointer to PCI device
 *
 * Restart the card from scratch, as if from a cold-boot. Implementation
 * resembles the first-half of the e1000_resume routine.
 */
static pci_ers_result_t atl1c_io_slot_reset(struct pci_dev *pdev)
{
        struct net_device *netdev = pci_get_drvdata(pdev);
        struct atl1c_adapter *adapter = netdev_priv(netdev);

        if (pci_enable_device(pdev)) {
                if (netif_msg_hw(adapter))
                        dev_err(&pdev->dev,
                                "Cannot re-enable PCI device after reset\n");
                return PCI_ERS_RESULT_DISCONNECT;
        }
        pci_set_master(pdev);

        pci_enable_wake(pdev, PCI_D3hot, 0);
        pci_enable_wake(pdev, PCI_D3cold, 0);

        atl1c_reset_mac(&adapter->hw);

        return PCI_ERS_RESULT_RECOVERED;
}

/**
 * atl1c_io_resume - called when traffic can start flowing again.
 * @pdev: Pointer to PCI device
 *
 * This callback is called when the error recovery driver tells us that
 * its OK to resume normal operation. Implementation resembles the
 * second-half of the atl1c_resume routine.
 */
static void atl1c_io_resume(struct pci_dev *pdev)
{
        struct net_device *netdev = pci_get_drvdata(pdev);
        struct atl1c_adapter *adapter = netdev_priv(netdev);

        if (netif_running(netdev)) {
                if (atl1c_up(adapter)) {
                        if (netif_msg_hw(adapter))
                                dev_err(&pdev->dev,
                                        "Cannot bring device back up after reset\n");
                        return;
                }
        }

        netif_device_attach(netdev);
}

static const struct pci_error_handlers atl1c_err_handler = {
        .error_detected = atl1c_io_error_detected,
        .slot_reset = atl1c_io_slot_reset,
        .resume = atl1c_io_resume,
};

static SIMPLE_DEV_PM_OPS(atl1c_pm_ops, atl1c_suspend, atl1c_resume);

static struct pci_driver atl1c_driver = {
        .name     = atl1c_driver_name,
        .id_table = atl1c_pci_tbl,
        .probe    = atl1c_probe,
        .remove   = atl1c_remove,
        .shutdown = atl1c_shutdown,
        .err_handler = &atl1c_err_handler,
        .driver.pm = &atl1c_pm_ops,
};

module_pci_driver(atl1c_driver);