/*
 * Copyright (C) 1999 - 2010 Intel Corporation.
 * Copyright (C) 2010 - 2012 LAPIS SEMICONDUCTOR CO., LTD.
 *
 * This code was derived from the Intel e1000e Linux driver.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2 of the License.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, see <http://www.gnu.org/licenses/>.
 */

#include "pch_gbe.h"
#include "pch_gbe_api.h"
#include <linux/module.h>
#include <linux/net_tstamp.h>
#include <linux/ptp_classify.h>
#include <linux/gpio.h>

#define DRV_VERSION     "1.01"
const char pch_driver_version[] = DRV_VERSION;

#define PCI_DEVICE_ID_INTEL_IOH1_GBE    0x8802          /* Pci device ID */
#define PCH_GBE_MAR_ENTRIES             16
#define PCH_GBE_SHORT_PKT               64
#define DSC_INIT16                      0xC000
#define PCH_GBE_DMA_ALIGN               0
#define PCH_GBE_DMA_PADDING             2
#define PCH_GBE_WATCHDOG_PERIOD         (5 * HZ)        /* watchdog time */
#define PCH_GBE_COPYBREAK_DEFAULT       256
#define PCH_GBE_PCI_BAR                 1
#define PCH_GBE_RESERVE_MEMORY          0x200000        /* 2MB */

/* Macros for ML7223 */
#define PCI_VENDOR_ID_ROHM                      0x10db
#define PCI_DEVICE_ID_ROHM_ML7223_GBE           0x8013

/* Macros for ML7831 */
#define PCI_DEVICE_ID_ROHM_ML7831_GBE           0x8802

#define PCH_GBE_TX_WEIGHT         64
#define PCH_GBE_RX_WEIGHT         64
#define PCH_GBE_RX_BUFFER_WRITE   16

/* Initialize the wake-on-LAN settings */
#define PCH_GBE_WL_INIT_SETTING    (PCH_GBE_WLC_MP)

#define PCH_GBE_MAC_RGMII_CTRL_SETTING ( \
        PCH_GBE_CHIP_TYPE_INTERNAL | \
        PCH_GBE_RGMII_MODE_RGMII     \
        )

/* Ethertype field values */
#define PCH_GBE_MAX_RX_BUFFER_SIZE      0x2880
#define PCH_GBE_MAX_JUMBO_FRAME_SIZE    10318
#define PCH_GBE_FRAME_SIZE_2048         2048
#define PCH_GBE_FRAME_SIZE_4096         4096
#define PCH_GBE_FRAME_SIZE_8192         8192

#define PCH_GBE_GET_DESC(R, i, type)    (&(((struct type *)((R).desc))[i]))
#define PCH_GBE_RX_DESC(R, i)           PCH_GBE_GET_DESC(R, i, pch_gbe_rx_desc)
#define PCH_GBE_TX_DESC(R, i)           PCH_GBE_GET_DESC(R, i, pch_gbe_tx_desc)
#define PCH_GBE_DESC_UNUSED(R) \
        ((((R)->next_to_clean > (R)->next_to_use) ? 0 : (R)->count) + \
        (R)->next_to_clean - (R)->next_to_use - 1)

/* Pause packet value */
#define PCH_GBE_PAUSE_PKT1_VALUE    0x00C28001
#define PCH_GBE_PAUSE_PKT2_VALUE    0x00000100
#define PCH_GBE_PAUSE_PKT4_VALUE    0x01000888
#define PCH_GBE_PAUSE_PKT5_VALUE    0x0000FFFF


/* This defines the bits that are set in the Interrupt Mask
 * Set/Read Register.  Each bit is documented below:
 *   o RXT0   = Receiver Timer Interrupt (ring 0)
 *   o TXDW   = Transmit Descriptor Written Back
 *   o RXDMT0 = Receive Descriptor Minimum Threshold hit (ring 0)
 *   o RXSEQ  = Receive Sequence Error
 *   o LSC    = Link Status Change
 */
#define PCH_GBE_INT_ENABLE_MASK ( \
        PCH_GBE_INT_RX_DMA_CMPLT |    \
        PCH_GBE_INT_RX_DSC_EMP   |    \
        PCH_GBE_INT_RX_FIFO_ERR  |    \
        PCH_GBE_INT_WOL_DET      |    \
        PCH_GBE_INT_TX_CMPLT          \
        )

#define PCH_GBE_INT_DISABLE_ALL         0

/* Macros for ieee1588 */
/* 0x40 Time Synchronization Channel Control Register Bits */
#define MASTER_MODE   (1<<0)
#define SLAVE_MODE    (0)
#define V2_MODE       (1<<31)
#define CAP_MODE0     (0)
#define CAP_MODE2     (1<<17)

/* 0x44 Time Synchronization Channel Event Register Bits */
#define TX_SNAPSHOT_LOCKED (1<<0)
#define RX_SNAPSHOT_LOCKED (1<<1)

#define PTP_L4_MULTICAST_SA "01:00:5e:00:01:81"
#define PTP_L2_MULTICAST_SA "01:1b:19:00:00:00"

#define MINNOW_PHY_RESET_GPIO           13

static unsigned int copybreak __read_mostly = PCH_GBE_COPYBREAK_DEFAULT;

static int pch_gbe_mdio_read(struct net_device *netdev, int addr, int reg);
static void pch_gbe_mdio_write(struct net_device *netdev, int addr, int reg,
                               int data);
static void pch_gbe_set_multi(struct net_device *netdev);

static int pch_ptp_match(struct sk_buff *skb, u16 uid_hi, u32 uid_lo, u16 seqid)
{
        u8 *data = skb->data;
        unsigned int offset;
        u16 *hi, *id;
        u32 lo;

        if (ptp_classify_raw(skb) == PTP_CLASS_NONE)
                return 0;

        offset = ETH_HLEN + IPV4_HLEN(data) + UDP_HLEN;

        if (skb->len < offset + OFF_PTP_SEQUENCE_ID + sizeof(seqid))
                return 0;

        hi = (u16 *)(data + offset + OFF_PTP_SOURCE_UUID);
        id = (u16 *)(data + offset + OFF_PTP_SEQUENCE_ID);

        memcpy(&lo, &hi[1], sizeof(lo));

        return (uid_hi == *hi &&
                uid_lo == lo &&
                seqid  == *id);
}

static void
pch_rx_timestamp(struct pch_gbe_adapter *adapter, struct sk_buff *skb)
{
        struct skb_shared_hwtstamps *shhwtstamps;
        struct pci_dev *pdev;
        u64 ns;
        u32 hi, lo, val;
        u16 uid, seq;

        if (!adapter->hwts_rx_en)
                return;

        /* Get ieee1588's dev information */
        pdev = adapter->ptp_pdev;

        val = pch_ch_event_read(pdev);

        if (!(val & RX_SNAPSHOT_LOCKED))
                return;

        lo = pch_src_uuid_lo_read(pdev);
        hi = pch_src_uuid_hi_read(pdev);

        uid = hi & 0xffff;
        seq = (hi >> 16) & 0xffff;

        if (!pch_ptp_match(skb, htons(uid), htonl(lo), htons(seq)))
                goto out;

        ns = pch_rx_snap_read(pdev);

        shhwtstamps = skb_hwtstamps(skb);
        memset(shhwtstamps, 0, sizeof(*shhwtstamps));
        shhwtstamps->hwtstamp = ns_to_ktime(ns);
out:
        pch_ch_event_write(pdev, RX_SNAPSHOT_LOCKED);
}

static void
pch_tx_timestamp(struct pch_gbe_adapter *adapter, struct sk_buff *skb)
{
        struct skb_shared_hwtstamps shhwtstamps;
        struct pci_dev *pdev;
        struct skb_shared_info *shtx;
        u64 ns;
        u32 cnt, val;

        shtx = skb_shinfo(skb);
        if (likely(!(shtx->tx_flags & SKBTX_HW_TSTAMP && adapter->hwts_tx_en)))
                return;

        shtx->tx_flags |= SKBTX_IN_PROGRESS;

        /* Get ieee1588's dev information */
        pdev = adapter->ptp_pdev;

        /*
         * This really stinks, but we have to poll for the Tx time stamp.
         */
        for (cnt = 0; cnt < 100; cnt++) {
                val = pch_ch_event_read(pdev);
                if (val & TX_SNAPSHOT_LOCKED)
                        break;
                udelay(1);
        }
        if (!(val & TX_SNAPSHOT_LOCKED)) {
                shtx->tx_flags &= ~SKBTX_IN_PROGRESS;
                return;
        }

        ns = pch_tx_snap_read(pdev);

        memset(&shhwtstamps, 0, sizeof(shhwtstamps));
        shhwtstamps.hwtstamp = ns_to_ktime(ns);
        skb_tstamp_tx(skb, &shhwtstamps);

        pch_ch_event_write(pdev, TX_SNAPSHOT_LOCKED);
}

static int hwtstamp_ioctl(struct net_device *netdev, struct ifreq *ifr, int cmd)
{
        struct hwtstamp_config cfg;
        struct pch_gbe_adapter *adapter = netdev_priv(netdev);
        struct pci_dev *pdev;
        u8 station[20];

        if (copy_from_user(&cfg, ifr->ifr_data, sizeof(cfg)))
                return -EFAULT;

        if (cfg.flags) /* reserved for future extensions */
                return -EINVAL;

        /* Get ieee1588's dev information */
        pdev = adapter->ptp_pdev;

        if (cfg.tx_type != HWTSTAMP_TX_OFF && cfg.tx_type != HWTSTAMP_TX_ON)
                return -ERANGE;

        switch (cfg.rx_filter) {
        case HWTSTAMP_FILTER_NONE:
                adapter->hwts_rx_en = 0;
                break;
        case HWTSTAMP_FILTER_PTP_V1_L4_SYNC:
                adapter->hwts_rx_en = 0;
                pch_ch_control_write(pdev, SLAVE_MODE | CAP_MODE0);
                break;
        case HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ:
                adapter->hwts_rx_en = 1;
                pch_ch_control_write(pdev, MASTER_MODE | CAP_MODE0);
                break;
        case HWTSTAMP_FILTER_PTP_V2_L4_EVENT:
                adapter->hwts_rx_en = 1;
                pch_ch_control_write(pdev, V2_MODE | CAP_MODE2);
                strcpy(station, PTP_L4_MULTICAST_SA);
                pch_set_station_address(station, pdev);
                break;
        case HWTSTAMP_FILTER_PTP_V2_L2_EVENT:
                adapter->hwts_rx_en = 1;
                pch_ch_control_write(pdev, V2_MODE | CAP_MODE2);
                strcpy(station, PTP_L2_MULTICAST_SA);
                pch_set_station_address(station, pdev);
                break;
        default:
                return -ERANGE;
        }

        adapter->hwts_tx_en = cfg.tx_type == HWTSTAMP_TX_ON;

        /* Clear out any old time stamps. */
        pch_ch_event_write(pdev, TX_SNAPSHOT_LOCKED | RX_SNAPSHOT_LOCKED);

        return copy_to_user(ifr->ifr_data, &cfg, sizeof(cfg)) ? -EFAULT : 0;
}

static inline void pch_gbe_mac_load_mac_addr(struct pch_gbe_hw *hw)
{
        iowrite32(0x01, &hw->reg->MAC_ADDR_LOAD);
}

/**
 * pch_gbe_mac_read_mac_addr - Read MAC address
 * @hw:             Pointer to the HW structure
 * Returns:
 *      0:                      Successful.
 */
s32 pch_gbe_mac_read_mac_addr(struct pch_gbe_hw *hw)
{
        struct pch_gbe_adapter *adapter = pch_gbe_hw_to_adapter(hw);
        u32  adr1a, adr1b;

        adr1a = ioread32(&hw->reg->mac_adr[0].high);
        adr1b = ioread32(&hw->reg->mac_adr[0].low);

        hw->mac.addr[0] = (u8)(adr1a & 0xFF);
        hw->mac.addr[1] = (u8)((adr1a >> 8) & 0xFF);
        hw->mac.addr[2] = (u8)((adr1a >> 16) & 0xFF);
        hw->mac.addr[3] = (u8)((adr1a >> 24) & 0xFF);
        hw->mac.addr[4] = (u8)(adr1b & 0xFF);
        hw->mac.addr[5] = (u8)((adr1b >> 8) & 0xFF);

        netdev_dbg(adapter->netdev, "hw->mac.addr : %pM\n", hw->mac.addr);
        return 0;
}

/**
 * pch_gbe_wait_clr_bit - Wait to clear a bit
 * @reg:        Pointer of register
 * @busy:       Busy bit
 */
static void pch_gbe_wait_clr_bit(void *reg, u32 bit)
{
        u32 tmp;

        /* wait busy */
        tmp = 1000;
        while ((ioread32(reg) & bit) && --tmp)
                cpu_relax();
        if (!tmp)
                pr_err("Error: busy bit is not cleared\n");
}

/**
 * pch_gbe_mac_mar_set - Set MAC address register
 * @hw:     Pointer to the HW structure
 * @addr:   Pointer to the MAC address
 * @index:  MAC address array register
 */
static void pch_gbe_mac_mar_set(struct pch_gbe_hw *hw, u8 * addr, u32 index)
{
        struct pch_gbe_adapter *adapter = pch_gbe_hw_to_adapter(hw);
        u32 mar_low, mar_high, adrmask;

        netdev_dbg(adapter->netdev, "index : 0x%x\n", index);

        /*
         * HW expects these in little endian so we reverse the byte order
         * from network order (big endian) to little endian
         */
        mar_high = ((u32) addr[0] | ((u32) addr[1] << 8) |
                   ((u32) addr[2] << 16) | ((u32) addr[3] << 24));
        mar_low = ((u32) addr[4] | ((u32) addr[5] << 8));
        /* Stop the MAC Address of index. */
        adrmask = ioread32(&hw->reg->ADDR_MASK);
        iowrite32((adrmask | (0x0001 << index)), &hw->reg->ADDR_MASK);
        /* wait busy */
        pch_gbe_wait_clr_bit(&hw->reg->ADDR_MASK, PCH_GBE_BUSY);
        /* Set the MAC address to the MAC address 1A/1B register */
        iowrite32(mar_high, &hw->reg->mac_adr[index].high);
        iowrite32(mar_low, &hw->reg->mac_adr[index].low);
        /* Start the MAC address of index */
        iowrite32((adrmask & ~(0x0001 << index)), &hw->reg->ADDR_MASK);
        /* wait busy */
        pch_gbe_wait_clr_bit(&hw->reg->ADDR_MASK, PCH_GBE_BUSY);
}

/**
 * pch_gbe_mac_reset_hw - Reset hardware
 * @hw: Pointer to the HW structure
 */
static void pch_gbe_mac_reset_hw(struct pch_gbe_hw *hw)
{
        /* Read the MAC address. and store to the private data */
        pch_gbe_mac_read_mac_addr(hw);
        iowrite32(PCH_GBE_ALL_RST, &hw->reg->RESET);
#ifdef PCH_GBE_MAC_IFOP_RGMII
        iowrite32(PCH_GBE_MODE_GMII_ETHER, &hw->reg->MODE);
#endif
        pch_gbe_wait_clr_bit(&hw->reg->RESET, PCH_GBE_ALL_RST);
        /* Setup the receive addresses */
        pch_gbe_mac_mar_set(hw, hw->mac.addr, 0);
        return;
}

static void pch_gbe_disable_mac_rx(struct pch_gbe_hw *hw)
{
        u32 rctl;
        /* Disables Receive MAC */
        rctl = ioread32(&hw->reg->MAC_RX_EN);
        iowrite32((rctl & ~PCH_GBE_MRE_MAC_RX_EN), &hw->reg->MAC_RX_EN);
}

static void pch_gbe_enable_mac_rx(struct pch_gbe_hw *hw)
{
        u32 rctl;
        /* Enables Receive MAC */
        rctl = ioread32(&hw->reg->MAC_RX_EN);
        iowrite32((rctl | PCH_GBE_MRE_MAC_RX_EN), &hw->reg->MAC_RX_EN);
}

/**
 * pch_gbe_mac_init_rx_addrs - Initialize receive address's
 * @hw: Pointer to the HW structure
 * @mar_count: Receive address registers
 */
static void pch_gbe_mac_init_rx_addrs(struct pch_gbe_hw *hw, u16 mar_count)
{
        u32 i;

        /* Setup the receive address */
        pch_gbe_mac_mar_set(hw, hw->mac.addr, 0);

        /* Zero out the other receive addresses */
        for (i = 1; i < mar_count; i++) {
                iowrite32(0, &hw->reg->mac_adr[i].high);
                iowrite32(0, &hw->reg->mac_adr[i].low);
        }
        iowrite32(0xFFFE, &hw->reg->ADDR_MASK);
        /* wait busy */
        pch_gbe_wait_clr_bit(&hw->reg->ADDR_MASK, PCH_GBE_BUSY);
}


/**
 * pch_gbe_mac_mc_addr_list_update - Update Multicast addresses
 * @hw:             Pointer to the HW structure
 * @mc_addr_list:   Array of multicast addresses to program
 * @mc_addr_count:  Number of multicast addresses to program
 * @mar_used_count: The first MAC Address register free to program
 * @mar_total_num:  Total number of supported MAC Address Registers
 */
static void pch_gbe_mac_mc_addr_list_update(struct pch_gbe_hw *hw,
                                            u8 *mc_addr_list, u32 mc_addr_count,
                                            u32 mar_used_count, u32 mar_total_num)
{
        u32 i, adrmask;

        /* Load the first set of multicast addresses into the exact
         * filters (RAR).  If there are not enough to fill the RAR
         * array, clear the filters.
         */
        for (i = mar_used_count; i < mar_total_num; i++) {
                if (mc_addr_count) {
                        pch_gbe_mac_mar_set(hw, mc_addr_list, i);
                        mc_addr_count--;
                        mc_addr_list += ETH_ALEN;
                } else {
                        /* Clear MAC address mask */
                        adrmask = ioread32(&hw->reg->ADDR_MASK);
                        iowrite32((adrmask | (0x0001 << i)),
                                        &hw->reg->ADDR_MASK);
                        /* wait busy */
                        pch_gbe_wait_clr_bit(&hw->reg->ADDR_MASK, PCH_GBE_BUSY);
                        /* Clear MAC address */
                        iowrite32(0, &hw->reg->mac_adr[i].high);
                        iowrite32(0, &hw->reg->mac_adr[i].low);
                }
        }
}

/**
 * pch_gbe_mac_force_mac_fc - Force the MAC's flow control settings
 * @hw:             Pointer to the HW structure
 * Returns:
 *      0:                      Successful.
 *      Negative value:         Failed.
 */
s32 pch_gbe_mac_force_mac_fc(struct pch_gbe_hw *hw)
{
        struct pch_gbe_adapter *adapter = pch_gbe_hw_to_adapter(hw);
        struct pch_gbe_mac_info *mac = &hw->mac;
        u32 rx_fctrl;

        netdev_dbg(adapter->netdev, "mac->fc = %u\n", mac->fc);

        rx_fctrl = ioread32(&hw->reg->RX_FCTRL);

        switch (mac->fc) {
        case PCH_GBE_FC_NONE:
                rx_fctrl &= ~PCH_GBE_FL_CTRL_EN;
                mac->tx_fc_enable = false;
                break;
        case PCH_GBE_FC_RX_PAUSE:
                rx_fctrl |= PCH_GBE_FL_CTRL_EN;
                mac->tx_fc_enable = false;
                break;
        case PCH_GBE_FC_TX_PAUSE:
                rx_fctrl &= ~PCH_GBE_FL_CTRL_EN;
                mac->tx_fc_enable = true;
                break;
        case PCH_GBE_FC_FULL:
                rx_fctrl |= PCH_GBE_FL_CTRL_EN;
                mac->tx_fc_enable = true;
                break;
        default:
                netdev_err(adapter->netdev,
                           "Flow control param set incorrectly\n");
                return -EINVAL;
        }
        if (mac->link_duplex == DUPLEX_HALF)
                rx_fctrl &= ~PCH_GBE_FL_CTRL_EN;
        iowrite32(rx_fctrl, &hw->reg->RX_FCTRL);
        netdev_dbg(adapter->netdev,
                   "RX_FCTRL reg : 0x%08x  mac->tx_fc_enable : %d\n",
                   ioread32(&hw->reg->RX_FCTRL), mac->tx_fc_enable);
        return 0;
}

/**
 * pch_gbe_mac_set_wol_event - Set wake-on-lan event
 * @hw:     Pointer to the HW structure
 * @wu_evt: Wake up event
 */
static void pch_gbe_mac_set_wol_event(struct pch_gbe_hw *hw, u32 wu_evt)
{
        struct pch_gbe_adapter *adapter = pch_gbe_hw_to_adapter(hw);
        u32 addr_mask;

        netdev_dbg(adapter->netdev, "wu_evt : 0x%08x  ADDR_MASK reg : 0x%08x\n",
                   wu_evt, ioread32(&hw->reg->ADDR_MASK));

        if (wu_evt) {
                /* Set Wake-On-Lan address mask */
                addr_mask = ioread32(&hw->reg->ADDR_MASK);
                iowrite32(addr_mask, &hw->reg->WOL_ADDR_MASK);
                /* wait busy */
                pch_gbe_wait_clr_bit(&hw->reg->WOL_ADDR_MASK, PCH_GBE_WLA_BUSY);
                iowrite32(0, &hw->reg->WOL_ST);
                iowrite32((wu_evt | PCH_GBE_WLC_WOL_MODE), &hw->reg->WOL_CTRL);
                iowrite32(0x02, &hw->reg->TCPIP_ACC);
                iowrite32(PCH_GBE_INT_ENABLE_MASK, &hw->reg->INT_EN);
        } else {
                iowrite32(0, &hw->reg->WOL_CTRL);
                iowrite32(0, &hw->reg->WOL_ST);
        }
        return;
}

/**
 * pch_gbe_mac_ctrl_miim - Control MIIM interface
 * @hw:   Pointer to the HW structure
 * @addr: Address of PHY
 * @dir:  Operetion. (Write or Read)
 * @reg:  Access register of PHY
 * @data: Write data.
 *
 * Returns: Read date.
 */
u16 pch_gbe_mac_ctrl_miim(struct pch_gbe_hw *hw, u32 addr, u32 dir, u32 reg,
                        u16 data)
{
        struct pch_gbe_adapter *adapter = pch_gbe_hw_to_adapter(hw);
        u32 data_out = 0;
        unsigned int i;
        unsigned long flags;

        spin_lock_irqsave(&hw->miim_lock, flags);

        for (i = 100; i; --i) {
                if ((ioread32(&hw->reg->MIIM) & PCH_GBE_MIIM_OPER_READY))
                        break;
                udelay(20);
        }
        if (i == 0) {
                netdev_err(adapter->netdev, "pch-gbe.miim won't go Ready\n");
                spin_unlock_irqrestore(&hw->miim_lock, flags);
                return 0;       /* No way to indicate timeout error */
        }
        iowrite32(((reg << PCH_GBE_MIIM_REG_ADDR_SHIFT) |
                  (addr << PCH_GBE_MIIM_PHY_ADDR_SHIFT) |
                  dir | data), &hw->reg->MIIM);
        for (i = 0; i < 100; i++) {
                udelay(20);
                data_out = ioread32(&hw->reg->MIIM);
                if ((data_out & PCH_GBE_MIIM_OPER_READY))
                        break;
        }
        spin_unlock_irqrestore(&hw->miim_lock, flags);

        netdev_dbg(adapter->netdev, "PHY %s: reg=%d, data=0x%04X\n",
                   dir == PCH_GBE_MIIM_OPER_READ ? "READ" : "WRITE", reg,
                   dir == PCH_GBE_MIIM_OPER_READ ? data_out : data);
        return (u16) data_out;
}

/**
 * pch_gbe_mac_set_pause_packet - Set pause packet
 * @hw:   Pointer to the HW structure
 */
static void pch_gbe_mac_set_pause_packet(struct pch_gbe_hw *hw)
{
        struct pch_gbe_adapter *adapter = pch_gbe_hw_to_adapter(hw);
        unsigned long tmp2, tmp3;

        /* Set Pause packet */
        tmp2 = hw->mac.addr[1];
        tmp2 = (tmp2 << 8) | hw->mac.addr[0];
        tmp2 = PCH_GBE_PAUSE_PKT2_VALUE | (tmp2 << 16);

        tmp3 = hw->mac.addr[5];
        tmp3 = (tmp3 << 8) | hw->mac.addr[4];
        tmp3 = (tmp3 << 8) | hw->mac.addr[3];
        tmp3 = (tmp3 << 8) | hw->mac.addr[2];

        iowrite32(PCH_GBE_PAUSE_PKT1_VALUE, &hw->reg->PAUSE_PKT1);
        iowrite32(tmp2, &hw->reg->PAUSE_PKT2);
        iowrite32(tmp3, &hw->reg->PAUSE_PKT3);
        iowrite32(PCH_GBE_PAUSE_PKT4_VALUE, &hw->reg->PAUSE_PKT4);
        iowrite32(PCH_GBE_PAUSE_PKT5_VALUE, &hw->reg->PAUSE_PKT5);

        /* Transmit Pause Packet */
        iowrite32(PCH_GBE_PS_PKT_RQ, &hw->reg->PAUSE_REQ);

        netdev_dbg(adapter->netdev,
                   "PAUSE_PKT1-5 reg : 0x%08x 0x%08x 0x%08x 0x%08x 0x%08x\n",
                   ioread32(&hw->reg->PAUSE_PKT1),
                   ioread32(&hw->reg->PAUSE_PKT2),
                   ioread32(&hw->reg->PAUSE_PKT3),
                   ioread32(&hw->reg->PAUSE_PKT4),
                   ioread32(&hw->reg->PAUSE_PKT5));

        return;
}


/**
 * pch_gbe_alloc_queues - Allocate memory for all rings
 * @adapter:  Board private structure to initialize
 * Returns:
 *      0:      Successfully
 *      Negative value: Failed
 */
static int pch_gbe_alloc_queues(struct pch_gbe_adapter *adapter)
{
        adapter->tx_ring = devm_kzalloc(&adapter->pdev->dev,
                                        sizeof(*adapter->tx_ring), GFP_KERNEL);
        if (!adapter->tx_ring)
                return -ENOMEM;

        adapter->rx_ring = devm_kzalloc(&adapter->pdev->dev,
                                        sizeof(*adapter->rx_ring), GFP_KERNEL);
        if (!adapter->rx_ring)
                return -ENOMEM;
        return 0;
}

/**
 * pch_gbe_init_stats - Initialize status
 * @adapter:  Board private structure to initialize
 */
static void pch_gbe_init_stats(struct pch_gbe_adapter *adapter)
{
        memset(&adapter->stats, 0, sizeof(adapter->stats));
        return;
}

/**
 * pch_gbe_init_phy - Initialize PHY
 * @adapter:  Board private structure to initialize
 * Returns:
 *      0:      Successfully
 *      Negative value: Failed
 */
static int pch_gbe_init_phy(struct pch_gbe_adapter *adapter)
{
        struct net_device *netdev = adapter->netdev;
        u32 addr;
        u16 bmcr, stat;

        /* Discover phy addr by searching addrs in order {1,0,2,..., 31} */
        for (addr = 0; addr < PCH_GBE_PHY_REGS_LEN; addr++) {
                adapter->mii.phy_id = (addr == 0) ? 1 : (addr == 1) ? 0 : addr;
                bmcr = pch_gbe_mdio_read(netdev, adapter->mii.phy_id, MII_BMCR);
                stat = pch_gbe_mdio_read(netdev, adapter->mii.phy_id, MII_BMSR);
                stat = pch_gbe_mdio_read(netdev, adapter->mii.phy_id, MII_BMSR);
                if (!((bmcr == 0xFFFF) || ((stat == 0) && (bmcr == 0))))
                        break;
        }
        adapter->hw.phy.addr = adapter->mii.phy_id;
        netdev_dbg(netdev, "phy_addr = %d\n", adapter->mii.phy_id);
        if (addr == PCH_GBE_PHY_REGS_LEN)
                return -EAGAIN;
        /* Selected the phy and isolate the rest */
        for (addr = 0; addr < PCH_GBE_PHY_REGS_LEN; addr++) {
                if (addr != adapter->mii.phy_id) {
                        pch_gbe_mdio_write(netdev, addr, MII_BMCR,
                                           BMCR_ISOLATE);
                } else {
                        bmcr = pch_gbe_mdio_read(netdev, addr, MII_BMCR);
                        pch_gbe_mdio_write(netdev, addr, MII_BMCR,
                                           bmcr & ~BMCR_ISOLATE);
                }
        }

        /* MII setup */
        adapter->mii.phy_id_mask = 0x1F;
        adapter->mii.reg_num_mask = 0x1F;
        adapter->mii.dev = adapter->netdev;
        adapter->mii.mdio_read = pch_gbe_mdio_read;
        adapter->mii.mdio_write = pch_gbe_mdio_write;
        adapter->mii.supports_gmii = mii_check_gmii_support(&adapter->mii);
        return 0;
}

/**
 * pch_gbe_mdio_read - The read function for mii
 * @netdev: Network interface device structure
 * @addr:   Phy ID
 * @reg:    Access location
 * Returns:
 *      0:      Successfully
 *      Negative value: Failed
 */
static int pch_gbe_mdio_read(struct net_device *netdev, int addr, int reg)
{
        struct pch_gbe_adapter *adapter = netdev_priv(netdev);
        struct pch_gbe_hw *hw = &adapter->hw;

        return pch_gbe_mac_ctrl_miim(hw, addr, PCH_GBE_HAL_MIIM_READ, reg,
                                     (u16) 0);
}

/**
 * pch_gbe_mdio_write - The write function for mii
 * @netdev: Network interface device structure
 * @addr:   Phy ID (not used)
 * @reg:    Access location
 * @data:   Write data
 */
static void pch_gbe_mdio_write(struct net_device *netdev,
                               int addr, int reg, int data)
{
        struct pch_gbe_adapter *adapter = netdev_priv(netdev);
        struct pch_gbe_hw *hw = &adapter->hw;

        pch_gbe_mac_ctrl_miim(hw, addr, PCH_GBE_HAL_MIIM_WRITE, reg, data);
}

/**
 * pch_gbe_reset_task - Reset processing at the time of transmission timeout
 * @work:  Pointer of board private structure
 */
static void pch_gbe_reset_task(struct work_struct *work)
{
        struct pch_gbe_adapter *adapter;
        adapter = container_of(work, struct pch_gbe_adapter, reset_task);

        rtnl_lock();
        pch_gbe_reinit_locked(adapter);
        rtnl_unlock();
}

/**
 * pch_gbe_reinit_locked- Re-initialization
 * @adapter:  Board private structure
 */
void pch_gbe_reinit_locked(struct pch_gbe_adapter *adapter)
{
        pch_gbe_down(adapter);
        pch_gbe_up(adapter);
}

/**
 * pch_gbe_reset - Reset GbE
 * @adapter:  Board private structure
 */
void pch_gbe_reset(struct pch_gbe_adapter *adapter)
{
        struct net_device *netdev = adapter->netdev;

        pch_gbe_mac_reset_hw(&adapter->hw);
        /* reprogram multicast address register after reset */
        pch_gbe_set_multi(netdev);
        /* Setup the receive address. */
        pch_gbe_mac_init_rx_addrs(&adapter->hw, PCH_GBE_MAR_ENTRIES);
        if (pch_gbe_hal_init_hw(&adapter->hw))
                netdev_err(netdev, "Hardware Error\n");
}

/**
 * pch_gbe_free_irq - Free an interrupt
 * @adapter:  Board private structure
 */
static void pch_gbe_free_irq(struct pch_gbe_adapter *adapter)
{
        struct net_device *netdev = adapter->netdev;

        free_irq(adapter->pdev->irq, netdev);
        if (adapter->have_msi) {
                pci_disable_msi(adapter->pdev);
                netdev_dbg(netdev, "call pci_disable_msi\n");
        }
}

/**
 * pch_gbe_irq_disable - Mask off interrupt generation on the NIC
 * @adapter:  Board private structure
 */
static void pch_gbe_irq_disable(struct pch_gbe_adapter *adapter)
{
        struct pch_gbe_hw *hw = &adapter->hw;

        atomic_inc(&adapter->irq_sem);
        iowrite32(0, &hw->reg->INT_EN);
        ioread32(&hw->reg->INT_ST);
        synchronize_irq(adapter->pdev->irq);

        netdev_dbg(adapter->netdev, "INT_EN reg : 0x%08x\n",
                   ioread32(&hw->reg->INT_EN));
}

/**
 * pch_gbe_irq_enable - Enable default interrupt generation settings
 * @adapter:  Board private structure
 */
static void pch_gbe_irq_enable(struct pch_gbe_adapter *adapter)
{
        struct pch_gbe_hw *hw = &adapter->hw;

        if (likely(atomic_dec_and_test(&adapter->irq_sem)))
                iowrite32(PCH_GBE_INT_ENABLE_MASK, &hw->reg->INT_EN);
        ioread32(&hw->reg->INT_ST);
        netdev_dbg(adapter->netdev, "INT_EN reg : 0x%08x\n",
                   ioread32(&hw->reg->INT_EN));
}



/**
 * pch_gbe_setup_tctl - configure the Transmit control registers
 * @adapter:  Board private structure
 */
static void pch_gbe_setup_tctl(struct pch_gbe_adapter *adapter)
{
        struct pch_gbe_hw *hw = &adapter->hw;
        u32 tx_mode, tcpip;

        tx_mode = PCH_GBE_TM_LONG_PKT |
                PCH_GBE_TM_ST_AND_FD |
                PCH_GBE_TM_SHORT_PKT |
                PCH_GBE_TM_TH_TX_STRT_8 |
                PCH_GBE_TM_TH_ALM_EMP_4 | PCH_GBE_TM_TH_ALM_FULL_8;

        iowrite32(tx_mode, &hw->reg->TX_MODE);

        tcpip = ioread32(&hw->reg->TCPIP_ACC);
        tcpip |= PCH_GBE_TX_TCPIPACC_EN;
        iowrite32(tcpip, &hw->reg->TCPIP_ACC);
        return;
}

/**
 * pch_gbe_configure_tx - Configure Transmit Unit after Reset
 * @adapter:  Board private structure
 */
static void pch_gbe_configure_tx(struct pch_gbe_adapter *adapter)
{
        struct pch_gbe_hw *hw = &adapter->hw;
        u32 tdba, tdlen, dctrl;

        netdev_dbg(adapter->netdev, "dma addr = 0x%08llx  size = 0x%08x\n",
                   (unsigned long long)adapter->tx_ring->dma,
                   adapter->tx_ring->size);

        /* Setup the HW Tx Head and Tail descriptor pointers */
        tdba = adapter->tx_ring->dma;
        tdlen = adapter->tx_ring->size - 0x10;
        iowrite32(tdba, &hw->reg->TX_DSC_BASE);
        iowrite32(tdlen, &hw->reg->TX_DSC_SIZE);
        iowrite32(tdba, &hw->reg->TX_DSC_SW_P);

        /* Enables Transmission DMA */
        dctrl = ioread32(&hw->reg->DMA_CTRL);
        dctrl |= PCH_GBE_TX_DMA_EN;
        iowrite32(dctrl, &hw->reg->DMA_CTRL);
}

/**
 * pch_gbe_setup_rctl - Configure the receive control registers
 * @adapter:  Board private structure
 */
static void pch_gbe_setup_rctl(struct pch_gbe_adapter *adapter)
{
        struct pch_gbe_hw *hw = &adapter->hw;
        u32 rx_mode, tcpip;

        rx_mode = PCH_GBE_ADD_FIL_EN | PCH_GBE_MLT_FIL_EN |
        PCH_GBE_RH_ALM_EMP_4 | PCH_GBE_RH_ALM_FULL_4 | PCH_GBE_RH_RD_TRG_8;

        iowrite32(rx_mode, &hw->reg->RX_MODE);

        tcpip = ioread32(&hw->reg->TCPIP_ACC);

        tcpip |= PCH_GBE_RX_TCPIPACC_OFF;
        tcpip &= ~PCH_GBE_RX_TCPIPACC_EN;
        iowrite32(tcpip, &hw->reg->TCPIP_ACC);
        return;
}

/**
 * pch_gbe_configure_rx - Configure Receive Unit after Reset
 * @adapter:  Board private structure
 */
static void pch_gbe_configure_rx(struct pch_gbe_adapter *adapter)
{
        struct pch_gbe_hw *hw = &adapter->hw;
        u32 rdba, rdlen, rxdma;

        netdev_dbg(adapter->netdev, "dma adr = 0x%08llx  size = 0x%08x\n",
                   (unsigned long long)adapter->rx_ring->dma,
                   adapter->rx_ring->size);

        pch_gbe_mac_force_mac_fc(hw);

        pch_gbe_disable_mac_rx(hw);

        /* Disables Receive DMA */
        rxdma = ioread32(&hw->reg->DMA_CTRL);
        rxdma &= ~PCH_GBE_RX_DMA_EN;
        iowrite32(rxdma, &hw->reg->DMA_CTRL);

        netdev_dbg(adapter->netdev,
                   "MAC_RX_EN reg = 0x%08x  DMA_CTRL reg = 0x%08x\n",
                   ioread32(&hw->reg->MAC_RX_EN),
                   ioread32(&hw->reg->DMA_CTRL));

        /* Setup the HW Rx Head and Tail Descriptor Pointers and
         * the Base and Length of the Rx Descriptor Ring */
        rdba = adapter->rx_ring->dma;
        rdlen = adapter->rx_ring->size - 0x10;
        iowrite32(rdba, &hw->reg->RX_DSC_BASE);
        iowrite32(rdlen, &hw->reg->RX_DSC_SIZE);
        iowrite32((rdba + rdlen), &hw->reg->RX_DSC_SW_P);
}

/**
 * pch_gbe_unmap_and_free_tx_resource - Unmap and free tx socket buffer
 * @adapter:     Board private structure
 * @buffer_info: Buffer information structure
 */
static void pch_gbe_unmap_and_free_tx_resource(
        struct pch_gbe_adapter *adapter, struct pch_gbe_buffer *buffer_info)
{
        if (buffer_info->mapped) {
                dma_unmap_single(&adapter->pdev->dev, buffer_info->dma,
                                 buffer_info->length, DMA_TO_DEVICE);
                buffer_info->mapped = false;
        }
        if (buffer_info->skb) {
                dev_kfree_skb_any(buffer_info->skb);
                buffer_info->skb = NULL;
        }
}

/**
 * pch_gbe_unmap_and_free_rx_resource - Unmap and free rx socket buffer
 * @adapter:      Board private structure
 * @buffer_info:  Buffer information structure
 */
static void pch_gbe_unmap_and_free_rx_resource(
                                        struct pch_gbe_adapter *adapter,
                                        struct pch_gbe_buffer *buffer_info)
{
        if (buffer_info->mapped) {
                dma_unmap_single(&adapter->pdev->dev, buffer_info->dma,
                                 buffer_info->length, DMA_FROM_DEVICE);
                buffer_info->mapped = false;
        }
        if (buffer_info->skb) {
                dev_kfree_skb_any(buffer_info->skb);
                buffer_info->skb = NULL;
        }
}

/**
 * pch_gbe_clean_tx_ring - Free Tx Buffers
 * @adapter:  Board private structure
 * @tx_ring:  Ring to be cleaned
 */
static void pch_gbe_clean_tx_ring(struct pch_gbe_adapter *adapter,
                                   struct pch_gbe_tx_ring *tx_ring)
{
        struct pch_gbe_hw *hw = &adapter->hw;
        struct pch_gbe_buffer *buffer_info;
        unsigned long size;
        unsigned int i;

        /* Free all the Tx ring sk_buffs */
        for (i = 0; i < tx_ring->count; i++) {
                buffer_info = &tx_ring->buffer_info[i];
                pch_gbe_unmap_and_free_tx_resource(adapter, buffer_info);
        }
        netdev_dbg(adapter->netdev,
                   "call pch_gbe_unmap_and_free_tx_resource() %d count\n", i);

        size = (unsigned long)sizeof(struct pch_gbe_buffer) * tx_ring->count;
        memset(tx_ring->buffer_info, 0, size);

        /* Zero out the descriptor ring */
        memset(tx_ring->desc, 0, tx_ring->size);
        tx_ring->next_to_use = 0;
        tx_ring->next_to_clean = 0;
        iowrite32(tx_ring->dma, &hw->reg->TX_DSC_HW_P);
        iowrite32((tx_ring->size - 0x10), &hw->reg->TX_DSC_SIZE);

}

/**
 * pch_gbe_clean_rx_ring - Free Rx Buffers
 * @adapter:  Board private structure
 * @rx_ring:  Ring to free buffers from
 */
static void
pch_gbe_clean_rx_ring(struct pch_gbe_adapter *adapter,
                      struct pch_gbe_rx_ring *rx_ring)
{
        struct pch_gbe_hw *hw = &adapter->hw;
        struct pch_gbe_buffer *buffer_info;
        unsigned long size;
        unsigned int i;

        /* Free all the Rx ring sk_buffs */
        for (i = 0; i < rx_ring->count; i++) {
                buffer_info = &rx_ring->buffer_info[i];
                pch_gbe_unmap_and_free_rx_resource(adapter, buffer_info);
        }
        netdev_dbg(adapter->netdev,
                   "call pch_gbe_unmap_and_free_rx_resource() %d count\n", i);
        size = (unsigned long)sizeof(struct pch_gbe_buffer) * rx_ring->count;
        memset(rx_ring->buffer_info, 0, size);

        /* Zero out the descriptor ring */
        memset(rx_ring->desc, 0, rx_ring->size);
        rx_ring->next_to_clean = 0;
        rx_ring->next_to_use = 0;
        iowrite32(rx_ring->dma, &hw->reg->RX_DSC_HW_P);
        iowrite32((rx_ring->size - 0x10), &hw->reg->RX_DSC_SIZE);
}

static void pch_gbe_set_rgmii_ctrl(struct pch_gbe_adapter *adapter, u16 speed,
                                    u16 duplex)
{
        struct pch_gbe_hw *hw = &adapter->hw;
        unsigned long rgmii = 0;

        /* Set the RGMII control. */
#ifdef PCH_GBE_MAC_IFOP_RGMII
        switch (speed) {
        case SPEED_10:
                rgmii = (PCH_GBE_RGMII_RATE_2_5M |
                         PCH_GBE_MAC_RGMII_CTRL_SETTING);
                break;
        case SPEED_100:
                rgmii = (PCH_GBE_RGMII_RATE_25M |
                         PCH_GBE_MAC_RGMII_CTRL_SETTING);
                break;
        case SPEED_1000:
                rgmii = (PCH_GBE_RGMII_RATE_125M |
                         PCH_GBE_MAC_RGMII_CTRL_SETTING);
                break;
        }
        iowrite32(rgmii, &hw->reg->RGMII_CTRL);
#else   /* GMII */
        rgmii = 0;
        iowrite32(rgmii, &hw->reg->RGMII_CTRL);
#endif
}
static void pch_gbe_set_mode(struct pch_gbe_adapter *adapter, u16 speed,
                              u16 duplex)
{
        struct net_device *netdev = adapter->netdev;
        struct pch_gbe_hw *hw = &adapter->hw;
        unsigned long mode = 0;

        /* Set the communication mode */
        switch (speed) {
        case SPEED_10:
                mode = PCH_GBE_MODE_MII_ETHER;
                netdev->tx_queue_len = 10;
                break;
        case SPEED_100:
                mode = PCH_GBE_MODE_MII_ETHER;
                netdev->tx_queue_len = 100;
                break;
        case SPEED_1000:
                mode = PCH_GBE_MODE_GMII_ETHER;
                break;
        }
        if (duplex == DUPLEX_FULL)
                mode |= PCH_GBE_MODE_FULL_DUPLEX;
        else
                mode |= PCH_GBE_MODE_HALF_DUPLEX;
        iowrite32(mode, &hw->reg->MODE);
}

/**
 * pch_gbe_watchdog - Watchdog process
 * @data:  Board private structure
 */
static void pch_gbe_watchdog(unsigned long data)
{
        struct pch_gbe_adapter *adapter = (struct pch_gbe_adapter *)data;
        struct net_device *netdev = adapter->netdev;
        struct pch_gbe_hw *hw = &adapter->hw;

        netdev_dbg(netdev, "right now = %ld\n", jiffies);

        pch_gbe_update_stats(adapter);
        if ((mii_link_ok(&adapter->mii)) && (!netif_carrier_ok(netdev))) {
                struct ethtool_cmd cmd = { .cmd = ETHTOOL_GSET };
                netdev->tx_queue_len = adapter->tx_queue_len;
                /* mii library handles link maintenance tasks */
                if (mii_ethtool_gset(&adapter->mii, &cmd)) {
                        netdev_err(netdev, "ethtool get setting Error\n");
                        mod_timer(&adapter->watchdog_timer,
                                  round_jiffies(jiffies +
                                                PCH_GBE_WATCHDOG_PERIOD));
                        return;
                }
                hw->mac.link_speed = ethtool_cmd_speed(&cmd);
                hw->mac.link_duplex = cmd.duplex;
                /* Set the RGMII control. */
                pch_gbe_set_rgmii_ctrl(adapter, hw->mac.link_speed,
                                                hw->mac.link_duplex);
                /* Set the communication mode */
                pch_gbe_set_mode(adapter, hw->mac.link_speed,
                                 hw->mac.link_duplex);
                netdev_dbg(netdev,
                           "Link is Up %d Mbps %s-Duplex\n",
                           hw->mac.link_speed,
                           cmd.duplex == DUPLEX_FULL ? "Full" : "Half");
                netif_carrier_on(netdev);
                netif_wake_queue(netdev);
        } else if ((!mii_link_ok(&adapter->mii)) &&
                   (netif_carrier_ok(netdev))) {
                netdev_dbg(netdev, "NIC Link is Down\n");
                hw->mac.link_speed = SPEED_10;
                hw->mac.link_duplex = DUPLEX_HALF;
                netif_carrier_off(netdev);
                netif_stop_queue(netdev);
        }
        mod_timer(&adapter->watchdog_timer,
                  round_jiffies(jiffies + PCH_GBE_WATCHDOG_PERIOD));
}

/**
 * pch_gbe_tx_queue - Carry out queuing of the transmission data
 * @adapter:  Board private structure
 * @tx_ring:  Tx descriptor ring structure
 * @skb:      Sockt buffer structure
 */
static void pch_gbe_tx_queue(struct pch_gbe_adapter *adapter,
                              struct pch_gbe_tx_ring *tx_ring,
                              struct sk_buff *skb)
{
        struct pch_gbe_hw *hw = &adapter->hw;
        struct pch_gbe_tx_desc *tx_desc;
        struct pch_gbe_buffer *buffer_info;
        struct sk_buff *tmp_skb;
        unsigned int frame_ctrl;
        unsigned int ring_num;

        /*-- Set frame control --*/
        frame_ctrl = 0;
        if (unlikely(skb->len < PCH_GBE_SHORT_PKT))
                frame_ctrl |= PCH_GBE_TXD_CTRL_APAD;
        if (skb->ip_summed == CHECKSUM_NONE)
                frame_ctrl |= PCH_GBE_TXD_CTRL_TCPIP_ACC_OFF;

        /* Performs checksum processing */
        /*
         * It is because the hardware accelerator does not support a checksum,
         * when the received data size is less than 64 bytes.
         */
        if (skb->len < PCH_GBE_SHORT_PKT && skb->ip_summed != CHECKSUM_NONE) {
                frame_ctrl |= PCH_GBE_TXD_CTRL_APAD |
                              PCH_GBE_TXD_CTRL_TCPIP_ACC_OFF;
                if (skb->protocol == htons(ETH_P_IP)) {
                        struct iphdr *iph = ip_hdr(skb);
                        unsigned int offset;
                        offset = skb_transport_offset(skb);
                        if (iph->protocol == IPPROTO_TCP) {
                                skb->csum = 0;
                                tcp_hdr(skb)->check = 0;
                                skb->csum = skb_checksum(skb, offset,
                                                         skb->len - offset, 0);
                                tcp_hdr(skb)->check =
                                        csum_tcpudp_magic(iph->saddr,
                                                          iph->daddr,
                                                          skb->len - offset,
                                                          IPPROTO_TCP,
                                                          skb->csum);
                        } else if (iph->protocol == IPPROTO_UDP) {
                                skb->csum = 0;
                                udp_hdr(skb)->check = 0;
                                skb->csum =
                                        skb_checksum(skb, offset,
                                                     skb->len - offset, 0);
                                udp_hdr(skb)->check =
                                        csum_tcpudp_magic(iph->saddr,
                                                          iph->daddr,
                                                          skb->len - offset,
                                                          IPPROTO_UDP,
                                                          skb->csum);
                        }
                }
        }

        ring_num = tx_ring->next_to_use;
        if (unlikely((ring_num + 1) == tx_ring->count))
                tx_ring->next_to_use = 0;
        else
                tx_ring->next_to_use = ring_num + 1;


        buffer_info = &tx_ring->buffer_info[ring_num];
        tmp_skb = buffer_info->skb;

        /* [Header:14][payload] ---> [Header:14][paddong:2][payload]    */
        memcpy(tmp_skb->data, skb->data, ETH_HLEN);
        tmp_skb->data[ETH_HLEN] = 0x00;
        tmp_skb->data[ETH_HLEN + 1] = 0x00;
        tmp_skb->len = skb->len;
        memcpy(&tmp_skb->data[ETH_HLEN + 2], &skb->data[ETH_HLEN],
               (skb->len - ETH_HLEN));
        /*-- Set Buffer information --*/
        buffer_info->length = tmp_skb->len;
        buffer_info->dma = dma_map_single(&adapter->pdev->dev, tmp_skb->data,
                                          buffer_info->length,
                                          DMA_TO_DEVICE);
        if (dma_mapping_error(&adapter->pdev->dev, buffer_info->dma)) {
                netdev_err(adapter->netdev, "TX DMA map failed\n");
                buffer_info->dma = 0;
                buffer_info->time_stamp = 0;
                tx_ring->next_to_use = ring_num;
                return;
        }
        buffer_info->mapped = true;
        buffer_info->time_stamp = jiffies;

        /*-- Set Tx descriptor --*/
        tx_desc = PCH_GBE_TX_DESC(*tx_ring, ring_num);
        tx_desc->buffer_addr = (buffer_info->dma);
        tx_desc->length = (tmp_skb->len);
        tx_desc->tx_words_eob = ((tmp_skb->len + 3));
        tx_desc->tx_frame_ctrl = (frame_ctrl);
        tx_desc->gbec_status = (DSC_INIT16);

        if (unlikely(++ring_num == tx_ring->count))
                ring_num = 0;

        /* Update software pointer of TX descriptor */
        iowrite32(tx_ring->dma +
                  (int)sizeof(struct pch_gbe_tx_desc) * ring_num,
                  &hw->reg->TX_DSC_SW_P);

        pch_tx_timestamp(adapter, skb);

        dev_kfree_skb_any(skb);
}

/**
 * pch_gbe_update_stats - Update the board statistics counters
 * @adapter:  Board private structure
 */
void pch_gbe_update_stats(struct pch_gbe_adapter *adapter)
{
        struct net_device *netdev = adapter->netdev;
        struct pci_dev *pdev = adapter->pdev;
        struct pch_gbe_hw_stats *stats = &adapter->stats;
        unsigned long flags;

        /*
         * Prevent stats update while adapter is being reset, or if the pci
         * connection is down.
         */
        if ((pdev->error_state) && (pdev->error_state != pci_channel_io_normal))
                return;

        spin_lock_irqsave(&adapter->stats_lock, flags);

        /* Update device status "adapter->stats" */
        stats->rx_errors = stats->rx_crc_errors + stats->rx_frame_errors;
        stats->tx_errors = stats->tx_length_errors +
            stats->tx_aborted_errors +
            stats->tx_carrier_errors + stats->tx_timeout_count;

        /* Update network device status "adapter->net_stats" */
        netdev->stats.rx_packets = stats->rx_packets;
        netdev->stats.rx_bytes = stats->rx_bytes;
        netdev->stats.rx_dropped = stats->rx_dropped;
        netdev->stats.tx_packets = stats->tx_packets;
        netdev->stats.tx_bytes = stats->tx_bytes;
        netdev->stats.tx_dropped = stats->tx_dropped;
        /* Fill out the OS statistics structure */
        netdev->stats.multicast = stats->multicast;
        netdev->stats.collisions = stats->collisions;
        /* Rx Errors */
        netdev->stats.rx_errors = stats->rx_errors;
        netdev->stats.rx_crc_errors = stats->rx_crc_errors;
        netdev->stats.rx_frame_errors = stats->rx_frame_errors;
        /* Tx Errors */
        netdev->stats.tx_errors = stats->tx_errors;
        netdev->stats.tx_aborted_errors = stats->tx_aborted_errors;
        netdev->stats.tx_carrier_errors = stats->tx_carrier_errors;

        spin_unlock_irqrestore(&adapter->stats_lock, flags);
}

static void pch_gbe_disable_dma_rx(struct pch_gbe_hw *hw)
{
        u32 rxdma;

        /* Disable Receive DMA */
        rxdma = ioread32(&hw->reg->DMA_CTRL);
        rxdma &= ~PCH_GBE_RX_DMA_EN;
        iowrite32(rxdma, &hw->reg->DMA_CTRL);
}

static void pch_gbe_enable_dma_rx(struct pch_gbe_hw *hw)
{
        u32 rxdma;

        /* Enables Receive DMA */
        rxdma = ioread32(&hw->reg->DMA_CTRL);
        rxdma |= PCH_GBE_RX_DMA_EN;
        iowrite32(rxdma, &hw->reg->DMA_CTRL);
}

/**
 * pch_gbe_intr - Interrupt Handler
 * @irq:   Interrupt number
 * @data:  Pointer to a network interface device structure
 * Returns:
 *      - IRQ_HANDLED:  Our interrupt
 *      - IRQ_NONE:     Not our interrupt
 */
static irqreturn_t pch_gbe_intr(int irq, void *data)
{
        struct net_device *netdev = data;
        struct pch_gbe_adapter *adapter = netdev_priv(netdev);
        struct pch_gbe_hw *hw = &adapter->hw;
        u32 int_st;
        u32 int_en;

        /* Check request status */
        int_st = ioread32(&hw->reg->INT_ST);
        int_st = int_st & ioread32(&hw->reg->INT_EN);
        /* When request status is no interruption factor */
        if (unlikely(!int_st))
                return IRQ_NONE;        /* Not our interrupt. End processing. */
        netdev_dbg(netdev, "%s occur int_st = 0x%08x\n", __func__, int_st);
        if (int_st & PCH_GBE_INT_RX_FRAME_ERR)
                adapter->stats.intr_rx_frame_err_count++;
        if (int_st & PCH_GBE_INT_RX_FIFO_ERR)
                if (!adapter->rx_stop_flag) {
                        adapter->stats.intr_rx_fifo_err_count++;
                        netdev_dbg(netdev, "Rx fifo over run\n");
                        adapter->rx_stop_flag = true;
                        int_en = ioread32(&hw->reg->INT_EN);
                        iowrite32((int_en & ~PCH_GBE_INT_RX_FIFO_ERR),
                                  &hw->reg->INT_EN);
                        pch_gbe_disable_dma_rx(&adapter->hw);
                        int_st |= ioread32(&hw->reg->INT_ST);
                        int_st = int_st & ioread32(&hw->reg->INT_EN);
                }
        if (int_st & PCH_GBE_INT_RX_DMA_ERR)
                adapter->stats.intr_rx_dma_err_count++;
        if (int_st & PCH_GBE_INT_TX_FIFO_ERR)
                adapter->stats.intr_tx_fifo_err_count++;
        if (int_st & PCH_GBE_INT_TX_DMA_ERR)
                adapter->stats.intr_tx_dma_err_count++;
        if (int_st & PCH_GBE_INT_TCPIP_ERR)
                adapter->stats.intr_tcpip_err_count++;
        /* When Rx descriptor is empty  */
        if ((int_st & PCH_GBE_INT_RX_DSC_EMP)) {
                adapter->stats.intr_rx_dsc_empty_count++;
                netdev_dbg(netdev, "Rx descriptor is empty\n");
                int_en = ioread32(&hw->reg->INT_EN);
                iowrite32((int_en & ~PCH_GBE_INT_RX_DSC_EMP), &hw->reg->INT_EN);
                if (hw->mac.tx_fc_enable) {
                        /* Set Pause packet */
                        pch_gbe_mac_set_pause_packet(hw);
                }
        }

        /* When request status is Receive interruption */
        if ((int_st & (PCH_GBE_INT_RX_DMA_CMPLT | PCH_GBE_INT_TX_CMPLT)) ||
            (adapter->rx_stop_flag)) {
                if (likely(napi_schedule_prep(&adapter->napi))) {
                        /* Enable only Rx Descriptor empty */
                        atomic_inc(&adapter->irq_sem);
                        int_en = ioread32(&hw->reg->INT_EN);
                        int_en &=
                            ~(PCH_GBE_INT_RX_DMA_CMPLT | PCH_GBE_INT_TX_CMPLT);
                        iowrite32(int_en, &hw->reg->INT_EN);
                        /* Start polling for NAPI */
                        __napi_schedule(&adapter->napi);
                }
        }
        netdev_dbg(netdev, "return = 0x%08x  INT_EN reg = 0x%08x\n",
                   IRQ_HANDLED, ioread32(&hw->reg->INT_EN));
        return IRQ_HANDLED;
}

/**
 * pch_gbe_alloc_rx_buffers - Replace used receive buffers; legacy & extended
 * @adapter:       Board private structure
 * @rx_ring:       Rx descriptor ring
 * @cleaned_count: Cleaned count
 */
static void
pch_gbe_alloc_rx_buffers(struct pch_gbe_adapter *adapter,
                         struct pch_gbe_rx_ring *rx_ring, int cleaned_count)
{
        struct net_device *netdev = adapter->netdev;
        struct pci_dev *pdev = adapter->pdev;
        struct pch_gbe_hw *hw = &adapter->hw;
        struct pch_gbe_rx_desc *rx_desc;
        struct pch_gbe_buffer *buffer_info;
        struct sk_buff *skb;
        unsigned int i;
        unsigned int bufsz;

        bufsz = adapter->rx_buffer_len + NET_IP_ALIGN;
        i = rx_ring->next_to_use;

        while ((cleaned_count--)) {
                buffer_info = &rx_ring->buffer_info[i];
                skb = netdev_alloc_skb(netdev, bufsz);
                if (unlikely(!skb)) {
                        /* Better luck next round */
                        adapter->stats.rx_alloc_buff_failed++;
                        break;
                }
                /* align */
                skb_reserve(skb, NET_IP_ALIGN);
                buffer_info->skb = skb;

                buffer_info->dma = dma_map_single(&pdev->dev,
                                                  buffer_info->rx_buffer,
                                                  buffer_info->length,
                                                  DMA_FROM_DEVICE);
                if (dma_mapping_error(&adapter->pdev->dev, buffer_info->dma)) {
                        dev_kfree_skb(skb);
                        buffer_info->skb = NULL;
                        buffer_info->dma = 0;
                        adapter->stats.rx_alloc_buff_failed++;
                        break; /* while !buffer_info->skb */
                }
                buffer_info->mapped = true;
                rx_desc = PCH_GBE_RX_DESC(*rx_ring, i);
                rx_desc->buffer_addr = (buffer_info->dma);
                rx_desc->gbec_status = DSC_INIT16;

                netdev_dbg(netdev,
                           "i = %d  buffer_info->dma = 0x08%llx  buffer_info->length = 0x%x\n",
                           i, (unsigned long long)buffer_info->dma,
                           buffer_info->length);

                if (unlikely(++i == rx_ring->count))
                        i = 0;
        }
        if (likely(rx_ring->next_to_use != i)) {
                rx_ring->next_to_use = i;
                if (unlikely(i-- == 0))
                        i = (rx_ring->count - 1);
                iowrite32(rx_ring->dma +
                          (int)sizeof(struct pch_gbe_rx_desc) * i,
                          &hw->reg->RX_DSC_SW_P);
        }
        return;
}

static int
pch_gbe_alloc_rx_buffers_pool(struct pch_gbe_adapter *adapter,
                         struct pch_gbe_rx_ring *rx_ring, int cleaned_count)
{
        struct pci_dev *pdev = adapter->pdev;
        struct pch_gbe_buffer *buffer_info;
        unsigned int i;
        unsigned int bufsz;
        unsigned int size;

        bufsz = adapter->rx_buffer_len;

        size = rx_ring->count * bufsz + PCH_GBE_RESERVE_MEMORY;
        rx_ring->rx_buff_pool =
                dma_zalloc_coherent(&pdev->dev, size,
                                    &rx_ring->rx_buff_pool_logic, GFP_KERNEL);
        if (!rx_ring->rx_buff_pool)
                return -ENOMEM;

        rx_ring->rx_buff_pool_size = size;
        for (i = 0; i < rx_ring->count; i++) {
                buffer_info = &rx_ring->buffer_info[i];
                buffer_info->rx_buffer = rx_ring->rx_buff_pool + bufsz * i;
                buffer_info->length = bufsz;
        }
        return 0;
}

/**
 * pch_gbe_alloc_tx_buffers - Allocate transmit buffers
 * @adapter:   Board private structure
 * @tx_ring:   Tx descriptor ring
 */
static void pch_gbe_alloc_tx_buffers(struct pch_gbe_adapter *adapter,
                                        struct pch_gbe_tx_ring *tx_ring)
{
        struct pch_gbe_buffer *buffer_info;
        struct sk_buff *skb;
        unsigned int i;
        unsigned int bufsz;
        struct pch_gbe_tx_desc *tx_desc;

        bufsz =
            adapter->hw.mac.max_frame_size + PCH_GBE_DMA_ALIGN + NET_IP_ALIGN;

        for (i = 0; i < tx_ring->count; i++) {
                buffer_info = &tx_ring->buffer_info[i];
                skb = netdev_alloc_skb(adapter->netdev, bufsz);
                skb_reserve(skb, PCH_GBE_DMA_ALIGN);
                buffer_info->skb = skb;
                tx_desc = PCH_GBE_TX_DESC(*tx_ring, i);
                tx_desc->gbec_status = (DSC_INIT16);
        }
        return;
}

/**
 * pch_gbe_clean_tx - Reclaim resources after transmit completes
 * @adapter:   Board private structure
 * @tx_ring:   Tx descriptor ring
 * Returns:
 *      true:  Cleaned the descriptor
 *      false: Not cleaned the descriptor
 */
static bool
pch_gbe_clean_tx(struct pch_gbe_adapter *adapter,
                 struct pch_gbe_tx_ring *tx_ring)
{
        struct pch_gbe_tx_desc *tx_desc;
        struct pch_gbe_buffer *buffer_info;
        struct sk_buff *skb;
        unsigned int i;
        unsigned int cleaned_count = 0;
        bool cleaned = false;
        int unused, thresh;

        netdev_dbg(adapter->netdev, "next_to_clean : %d\n",
                   tx_ring->next_to_clean);

        i = tx_ring->next_to_clean;
        tx_desc = PCH_GBE_TX_DESC(*tx_ring, i);
        netdev_dbg(adapter->netdev, "gbec_status:0x%04x  dma_status:0x%04x\n",
                   tx_desc->gbec_status, tx_desc->dma_status);

        unused = PCH_GBE_DESC_UNUSED(tx_ring);
        thresh = tx_ring->count - PCH_GBE_TX_WEIGHT;
        if ((tx_desc->gbec_status == DSC_INIT16) && (unused < thresh))
        {  /* current marked clean, tx queue filling up, do extra clean */
                int j, k;
                if (unused < 8) {  /* tx queue nearly full */
                        netdev_dbg(adapter->netdev,
                                   "clean_tx: transmit queue warning (%x,%x) unused=%d\n",
                                   tx_ring->next_to_clean, tx_ring->next_to_use,
                                   unused);
                }

                /* current marked clean, scan for more that need cleaning. */
                k = i;
                for (j = 0; j < PCH_GBE_TX_WEIGHT; j++)
                {
                        tx_desc = PCH_GBE_TX_DESC(*tx_ring, k);
                        if (tx_desc->gbec_status != DSC_INIT16) break; /*found*/
                        if (++k >= tx_ring->count) k = 0;  /*increment, wrap*/
                }
                if (j < PCH_GBE_TX_WEIGHT) {
                        netdev_dbg(adapter->netdev,
                                   "clean_tx: unused=%d loops=%d found tx_desc[%x,%x:%x].gbec_status=%04x\n",
                                   unused, j, i, k, tx_ring->next_to_use,
                                   tx_desc->gbec_status);
                        i = k;  /*found one to clean, usu gbec_status==2000.*/
                }
        }

        while ((tx_desc->gbec_status & DSC_INIT16) == 0x0000) {
                netdev_dbg(adapter->netdev, "gbec_status:0x%04x\n",
                           tx_desc->gbec_status);
                buffer_info = &tx_ring->buffer_info[i];
                skb = buffer_info->skb;
                cleaned = true;

                if ((tx_desc->gbec_status & PCH_GBE_TXD_GMAC_STAT_ABT)) {
                        adapter->stats.tx_aborted_errors++;
                        netdev_err(adapter->netdev, "Transfer Abort Error\n");
                } else if ((tx_desc->gbec_status & PCH_GBE_TXD_GMAC_STAT_CRSER)
                          ) {
                        adapter->stats.tx_carrier_errors++;
                        netdev_err(adapter->netdev,
                                   "Transfer Carrier Sense Error\n");
                } else if ((tx_desc->gbec_status & PCH_GBE_TXD_GMAC_STAT_EXCOL)
                          ) {
                        adapter->stats.tx_aborted_errors++;
                        netdev_err(adapter->netdev,
                                   "Transfer Collision Abort Error\n");
                } else if ((tx_desc->gbec_status &
                            (PCH_GBE_TXD_GMAC_STAT_SNGCOL |
                             PCH_GBE_TXD_GMAC_STAT_MLTCOL))) {
                        adapter->stats.collisions++;
                        adapter->stats.tx_packets++;
                        adapter->stats.tx_bytes += skb->len;
                        netdev_dbg(adapter->netdev, "Transfer Collision\n");
                } else if ((tx_desc->gbec_status & PCH_GBE_TXD_GMAC_STAT_CMPLT)
                          ) {
                        adapter->stats.tx_packets++;
                        adapter->stats.tx_bytes += skb->len;
                }
                if (buffer_info->mapped) {
                        netdev_dbg(adapter->netdev,
                                   "unmap buffer_info->dma : %d\n", i);
                        dma_unmap_single(&adapter->pdev->dev, buffer_info->dma,
                                         buffer_info->length, DMA_TO_DEVICE);
                        buffer_info->mapped = false;
                }
                if (buffer_info->skb) {
                        netdev_dbg(adapter->netdev,
                                   "trim buffer_info->skb : %d\n", i);
                        skb_trim(buffer_info->skb, 0);
                }
                tx_desc->gbec_status = DSC_INIT16;
                if (unlikely(++i == tx_ring->count))
                        i = 0;
                tx_desc = PCH_GBE_TX_DESC(*tx_ring, i);

                /* weight of a sort for tx, to avoid endless transmit cleanup */
                if (cleaned_count++ == PCH_GBE_TX_WEIGHT) {
                        cleaned = false;
                        break;
                }
        }
        netdev_dbg(adapter->netdev,
                   "called pch_gbe_unmap_and_free_tx_resource() %d count\n",
                   cleaned_count);
        if (cleaned_count > 0)  { /*skip this if nothing cleaned*/
                /* Recover from running out of Tx resources in xmit_frame */
                netif_tx_lock(adapter->netdev);
                if (unlikely(cleaned && (netif_queue_stopped(adapter->netdev))))
                {
                        netif_wake_queue(adapter->netdev);
                        adapter->stats.tx_restart_count++;
                        netdev_dbg(adapter->netdev, "Tx wake queue\n");
                }

                tx_ring->next_to_clean = i;

                netdev_dbg(adapter->netdev, "next_to_clean : %d\n",
                           tx_ring->next_to_clean);
                netif_tx_unlock(adapter->netdev);
        }
        return cleaned;
}

/**
 * pch_gbe_clean_rx - Send received data up the network stack; legacy
 * @adapter:     Board private structure
 * @rx_ring:     Rx descriptor ring
 * @work_done:   Completed count
 * @work_to_do:  Request count
 * Returns:
 *      true:  Cleaned the descriptor
 *      false: Not cleaned the descriptor
 */
static bool
pch_gbe_clean_rx(struct pch_gbe_adapter *adapter,
                 struct pch_gbe_rx_ring *rx_ring,
                 int *work_done, int work_to_do)
{
        struct net_device *netdev = adapter->netdev;
        struct pci_dev *pdev = adapter->pdev;
        struct pch_gbe_buffer *buffer_info;
        struct pch_gbe_rx_desc *rx_desc;
        u32 length;
        unsigned int i;
        unsigned int cleaned_count = 0;
        bool cleaned = false;
        struct sk_buff *skb;
        u8 dma_status;
        u16 gbec_status;
        u32 tcp_ip_status;

        i = rx_ring->next_to_clean;

        while (*work_done < work_to_do) {
                /* Check Rx descriptor status */
                rx_desc = PCH_GBE_RX_DESC(*rx_ring, i);
                if (rx_desc->gbec_status == DSC_INIT16)
                        break;
                cleaned = true;
                cleaned_count++;

                dma_status = rx_desc->dma_status;
                gbec_status = rx_desc->gbec_status;
                tcp_ip_status = rx_desc->tcp_ip_status;
                rx_desc->gbec_status = DSC_INIT16;
                buffer_info = &rx_ring->buffer_info[i];
                skb = buffer_info->skb;
                buffer_info->skb = NULL;

                /* unmap dma */
                dma_unmap_single(&pdev->dev, buffer_info->dma,
                                   buffer_info->length, DMA_FROM_DEVICE);
                buffer_info->mapped = false;

                netdev_dbg(netdev,
                           "RxDecNo = 0x%04x  Status[DMA:0x%02x GBE:0x%04x TCP:0x%08x]  BufInf = 0x%p\n",
                           i, dma_status, gbec_status, tcp_ip_status,
                           buffer_info);
                /* Error check */
                if (unlikely(gbec_status & PCH_GBE_RXD_GMAC_STAT_NOTOCTAL)) {
                        adapter->stats.rx_frame_errors++;
                        netdev_err(netdev, "Receive Not Octal Error\n");
                } else if (unlikely(gbec_status &
                                PCH_GBE_RXD_GMAC_STAT_NBLERR)) {
                        adapter->stats.rx_frame_errors++;
                        netdev_err(netdev, "Receive Nibble Error\n");
                } else if (unlikely(gbec_status &
                                PCH_GBE_RXD_GMAC_STAT_CRCERR)) {
                        adapter->stats.rx_crc_errors++;
                        netdev_err(netdev, "Receive CRC Error\n");
                } else {
                        /* get receive length */
                        /* length convert[-3], length includes FCS length */
                        length = (rx_desc->rx_words_eob) - 3 - ETH_FCS_LEN;
                        if (rx_desc->rx_words_eob & 0x02)
                                length = length - 4;
                        /*
                         * buffer_info->rx_buffer: [Header:14][payload]
                         * skb->data: [Reserve:2][Header:14][payload]
                         */
                        memcpy(skb->data, buffer_info->rx_buffer, length);

                        /* update status of driver */
                        adapter->stats.rx_bytes += length;
                        adapter->stats.rx_packets++;
                        if ((gbec_status & PCH_GBE_RXD_GMAC_STAT_MARMLT))
                                adapter->stats.multicast++;
                        /* Write meta date of skb */
                        skb_put(skb, length);

                        pch_rx_timestamp(adapter, skb);

                        skb->protocol = eth_type_trans(skb, netdev);
                        if (tcp_ip_status & PCH_GBE_RXD_ACC_STAT_TCPIPOK)
                                skb->ip_summed = CHECKSUM_UNNECESSARY;
                        else
                                skb->ip_summed = CHECKSUM_NONE;

                        napi_gro_receive(&adapter->napi, skb);
                        (*work_done)++;
                        netdev_dbg(netdev,
                                   "Receive skb->ip_summed: %d length: %d\n",
                                   skb->ip_summed, length);
                }
                /* return some buffers to hardware, one at a time is too slow */
                if (unlikely(cleaned_count >= PCH_GBE_RX_BUFFER_WRITE)) {
                        pch_gbe_alloc_rx_buffers(adapter, rx_ring,
                                                 cleaned_count);
                        cleaned_count = 0;
                }
                if (++i == rx_ring->count)
                        i = 0;
        }
        rx_ring->next_to_clean = i;
        if (cleaned_count)
                pch_gbe_alloc_rx_buffers(adapter, rx_ring, cleaned_count);
        return cleaned;
}

/**
 * pch_gbe_setup_tx_resources - Allocate Tx resources (Descriptors)
 * @adapter:  Board private structure
 * @tx_ring:  Tx descriptor ring (for a specific queue) to setup
 * Returns:
 *      0:              Successfully
 *      Negative value: Failed
 */
int pch_gbe_setup_tx_resources(struct pch_gbe_adapter *adapter,
                                struct pch_gbe_tx_ring *tx_ring)
{
        struct pci_dev *pdev = adapter->pdev;
        struct pch_gbe_tx_desc *tx_desc;
        int size;
        int desNo;

        size = (int)sizeof(struct pch_gbe_buffer) * tx_ring->count;
        tx_ring->buffer_info = vzalloc(size);
        if (!tx_ring->buffer_info)
                return -ENOMEM;

        tx_ring->size = tx_ring->count * (int)sizeof(struct pch_gbe_tx_desc);

        tx_ring->desc = dma_zalloc_coherent(&pdev->dev, tx_ring->size,
                                            &tx_ring->dma, GFP_KERNEL);
        if (!tx_ring->desc) {
                vfree(tx_ring->buffer_info);
                return -ENOMEM;
        }

        tx_ring->next_to_use = 0;
        tx_ring->next_to_clean = 0;

        for (desNo = 0; desNo < tx_ring->count; desNo++) {
                tx_desc = PCH_GBE_TX_DESC(*tx_ring, desNo);
                tx_desc->gbec_status = DSC_INIT16;
        }
        netdev_dbg(adapter->netdev,
                   "tx_ring->desc = 0x%p  tx_ring->dma = 0x%08llx next_to_clean = 0x%08x  next_to_use = 0x%08x\n",
                   tx_ring->desc, (unsigned long long)tx_ring->dma,
                   tx_ring->next_to_clean, tx_ring->next_to_use);
        return 0;
}

/**
 * pch_gbe_setup_rx_resources - Allocate Rx resources (Descriptors)
 * @adapter:  Board private structure
 * @rx_ring:  Rx descriptor ring (for a specific queue) to setup
 * Returns:
 *      0:              Successfully
 *      Negative value: Failed
 */
int pch_gbe_setup_rx_resources(struct pch_gbe_adapter *adapter,
                                struct pch_gbe_rx_ring *rx_ring)
{
        struct pci_dev *pdev = adapter->pdev;
        struct pch_gbe_rx_desc *rx_desc;
        int size;
        int desNo;

        size = (int)sizeof(struct pch_gbe_buffer) * rx_ring->count;
        rx_ring->buffer_info = vzalloc(size);
        if (!rx_ring->buffer_info)
                return -ENOMEM;

        rx_ring->size = rx_ring->count * (int)sizeof(struct pch_gbe_rx_desc);
        rx_ring->desc = dma_zalloc_coherent(&pdev->dev, rx_ring->size,
                                            &rx_ring->dma, GFP_KERNEL);
        if (!rx_ring->desc) {
                vfree(rx_ring->buffer_info);
                return -ENOMEM;
        }
        rx_ring->next_to_clean = 0;
        rx_ring->next_to_use = 0;
        for (desNo = 0; desNo < rx_ring->count; desNo++) {
                rx_desc = PCH_GBE_RX_DESC(*rx_ring, desNo);
                rx_desc->gbec_status = DSC_INIT16;
        }
        netdev_dbg(adapter->netdev,
                   "rx_ring->desc = 0x%p  rx_ring->dma = 0x%08llx next_to_clean = 0x%08x  next_to_use = 0x%08x\n",
                   rx_ring->desc, (unsigned long long)rx_ring->dma,
                   rx_ring->next_to_clean, rx_ring->next_to_use);
        return 0;
}

/**
 * pch_gbe_free_tx_resources - Free Tx Resources
 * @adapter:  Board private structure
 * @tx_ring:  Tx descriptor ring for a specific queue
 */
void pch_gbe_free_tx_resources(struct pch_gbe_adapter *adapter,
                                struct pch_gbe_tx_ring *tx_ring)
{
        struct pci_dev *pdev = adapter->pdev;

        pch_gbe_clean_tx_ring(adapter, tx_ring);
        vfree(tx_ring->buffer_info);
        tx_ring->buffer_info = NULL;
        pci_free_consistent(pdev, tx_ring->size, tx_ring->desc, tx_ring->dma);
        tx_ring->desc = NULL;
}

/**
 * pch_gbe_free_rx_resources - Free Rx Resources
 * @adapter:  Board private structure
 * @rx_ring:  Ring to clean the resources from
 */
void pch_gbe_free_rx_resources(struct pch_gbe_adapter *adapter,
                                struct pch_gbe_rx_ring *rx_ring)
{
        struct pci_dev *pdev = adapter->pdev;

        pch_gbe_clean_rx_ring(adapter, rx_ring);
        vfree(rx_ring->buffer_info);
        rx_ring->buffer_info = NULL;
        pci_free_consistent(pdev, rx_ring->size, rx_ring->desc, rx_ring->dma);
        rx_ring->desc = NULL;
}

/**
 * pch_gbe_request_irq - Allocate an interrupt line
 * @adapter:  Board private structure
 * Returns:
 *      0:              Successfully
 *      Negative value: Failed
 */
static int pch_gbe_request_irq(struct pch_gbe_adapter *adapter)
{
        struct net_device *netdev = adapter->netdev;
        int err;
        int flags;

        flags = IRQF_SHARED;
        adapter->have_msi = false;
        err = pci_enable_msi(adapter->pdev);
        netdev_dbg(netdev, "call pci_enable_msi\n");
        if (err) {
                netdev_dbg(netdev, "call pci_enable_msi - Error: %d\n", err);
        } else {
                flags = 0;
                adapter->have_msi = true;
        }
        err = request_irq(adapter->pdev->irq, &pch_gbe_intr,
                          flags, netdev->name, netdev);
        if (err)
                netdev_err(netdev, "Unable to allocate interrupt Error: %d\n",
                           err);
        netdev_dbg(netdev,
                   "adapter->have_msi : %d  flags : 0x%04x  return : 0x%04x\n",
                   adapter->have_msi, flags, err);
        return err;
}


/**
 * pch_gbe_up - Up GbE network device
 * @adapter:  Board private structure
 * Returns:
 *      0:              Successfully
 *      Negative value: Failed
 */
int pch_gbe_up(struct pch_gbe_adapter *adapter)
{
        struct net_device *netdev = adapter->netdev;
        struct pch_gbe_tx_ring *tx_ring = adapter->tx_ring;
        struct pch_gbe_rx_ring *rx_ring = adapter->rx_ring;
        int err = -EINVAL;

        /* Ensure we have a valid MAC */
        if (!is_valid_ether_addr(adapter->hw.mac.addr)) {
                netdev_err(netdev, "Error: Invalid MAC address\n");
                goto out;
        }

        /* hardware has been reset, we need to reload some things */
        pch_gbe_set_multi(netdev);

        pch_gbe_setup_tctl(adapter);
        pch_gbe_configure_tx(adapter);
        pch_gbe_setup_rctl(adapter);
        pch_gbe_configure_rx(adapter);

        err = pch_gbe_request_irq(adapter);
        if (err) {
                netdev_err(netdev,
                           "Error: can't bring device up - irq request failed\n");
                goto out;
        }
        err = pch_gbe_alloc_rx_buffers_pool(adapter, rx_ring, rx_ring->count);
        if (err) {
                netdev_err(netdev,
                           "Error: can't bring device up - alloc rx buffers pool failed\n");
                goto freeirq;
        }
        pch_gbe_alloc_tx_buffers(adapter, tx_ring);
        pch_gbe_alloc_rx_buffers(adapter, rx_ring, rx_ring->count);
        adapter->tx_queue_len = netdev->tx_queue_len;
        pch_gbe_enable_dma_rx(&adapter->hw);
        pch_gbe_enable_mac_rx(&adapter->hw);

        mod_timer(&adapter->watchdog_timer, jiffies);

        napi_enable(&adapter->napi);
        pch_gbe_irq_enable(adapter);
        netif_start_queue(adapter->netdev);

        return 0;

freeirq:
        pch_gbe_free_irq(adapter);
out:
        return err;
}

/**
 * pch_gbe_down - Down GbE network device
 * @adapter:  Board private structure
 */
void pch_gbe_down(struct pch_gbe_adapter *adapter)
{
        struct net_device *netdev = adapter->netdev;
        struct pci_dev *pdev = adapter->pdev;
        struct pch_gbe_rx_ring *rx_ring = adapter->rx_ring;

        /* signal that we're down so the interrupt handler does not

         * reschedule our watchdog timer */
        napi_disable(&adapter->napi);
        atomic_set(&adapter->irq_sem, 0);

        pch_gbe_irq_disable(adapter);
        pch_gbe_free_irq(adapter);

        del_timer_sync(&adapter->watchdog_timer);

        netdev->tx_queue_len = adapter->tx_queue_len;
        netif_carrier_off(netdev);
        netif_stop_queue(netdev);

        if ((pdev->error_state) && (pdev->error_state != pci_channel_io_normal))
                pch_gbe_reset(adapter);
        pch_gbe_clean_tx_ring(adapter, adapter->tx_ring);
        pch_gbe_clean_rx_ring(adapter, adapter->rx_ring);

        pci_free_consistent(adapter->pdev, rx_ring->rx_buff_pool_size,
                            rx_ring->rx_buff_pool, rx_ring->rx_buff_pool_logic);
        rx_ring->rx_buff_pool_logic = 0;
        rx_ring->rx_buff_pool_size = 0;
        rx_ring->rx_buff_pool = NULL;
}

/**
 * pch_gbe_sw_init - Initialize general software structures (struct pch_gbe_adapter)
 * @adapter:  Board private structure to initialize
 * Returns:
 *      0:              Successfully
 *      Negative value: Failed
 */
static int pch_gbe_sw_init(struct pch_gbe_adapter *adapter)
{
        struct pch_gbe_hw *hw = &adapter->hw;
        struct net_device *netdev = adapter->netdev;

        adapter->rx_buffer_len = PCH_GBE_FRAME_SIZE_2048;
        hw->mac.max_frame_size = netdev->mtu + ETH_HLEN + ETH_FCS_LEN;
        hw->mac.min_frame_size = ETH_ZLEN + ETH_FCS_LEN;

        /* Initialize the hardware-specific values */
        if (pch_gbe_hal_setup_init_funcs(hw)) {
                netdev_err(netdev, "Hardware Initialization Failure\n");
                return -EIO;
        }
        if (pch_gbe_alloc_queues(adapter)) {
                netdev_err(netdev, "Unable to allocate memory for queues\n");
                return -ENOMEM;
        }
        spin_lock_init(&adapter->hw.miim_lock);
        spin_lock_init(&adapter->stats_lock);
        spin_lock_init(&adapter->ethtool_lock);
        atomic_set(&adapter->irq_sem, 0);
        pch_gbe_irq_disable(adapter);

        pch_gbe_init_stats(adapter);

        netdev_dbg(netdev,
                   "rx_buffer_len : %d  mac.min_frame_size : %d  mac.max_frame_size : %d\n",
                   (u32) adapter->rx_buffer_len,
                   hw->mac.min_frame_size, hw->mac.max_frame_size);
        return 0;
}

/**
 * pch_gbe_open - Called when a network interface is made active
 * @netdev:     Network interface device structure
 * Returns:
 *      0:              Successfully
 *      Negative value: Failed
 */
static int pch_gbe_open(struct net_device *netdev)
{
        struct pch_gbe_adapter *adapter = netdev_priv(netdev);
        struct pch_gbe_hw *hw = &adapter->hw;
        int err;

        /* allocate transmit descriptors */
        err = pch_gbe_setup_tx_resources(adapter, adapter->tx_ring);
        if (err)
                goto err_setup_tx;
        /* allocate receive descriptors */
        err = pch_gbe_setup_rx_resources(adapter, adapter->rx_ring);
        if (err)
                goto err_setup_rx;
        pch_gbe_hal_power_up_phy(hw);
        err = pch_gbe_up(adapter);
        if (err)
                goto err_up;
        netdev_dbg(netdev, "Success End\n");
        return 0;

err_up:
        if (!adapter->wake_up_evt)
                pch_gbe_hal_power_down_phy(hw);
        pch_gbe_free_rx_resources(adapter, adapter->rx_ring);
err_setup_rx:
        pch_gbe_free_tx_resources(adapter, adapter->tx_ring);
err_setup_tx:
        pch_gbe_reset(adapter);
        netdev_err(netdev, "Error End\n");
        return err;
}

/**
 * pch_gbe_stop - Disables a network interface
 * @netdev:  Network interface device structure
 * Returns:
 *      0: Successfully
 */
static int pch_gbe_stop(struct net_device *netdev)
{
        struct pch_gbe_adapter *adapter = netdev_priv(netdev);
        struct pch_gbe_hw *hw = &adapter->hw;

        pch_gbe_down(adapter);
        if (!adapter->wake_up_evt)
                pch_gbe_hal_power_down_phy(hw);
        pch_gbe_free_tx_resources(adapter, adapter->tx_ring);
        pch_gbe_free_rx_resources(adapter, adapter->rx_ring);
        return 0;
}

/**
 * pch_gbe_xmit_frame - Packet transmitting start
 * @skb:     Socket buffer structure
 * @netdev:  Network interface device structure
 * Returns:
 *      - NETDEV_TX_OK:   Normal end
 *      - NETDEV_TX_BUSY: Error end
 */
static int pch_gbe_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
{
        struct pch_gbe_adapter *adapter = netdev_priv(netdev);
        struct pch_gbe_tx_ring *tx_ring = adapter->tx_ring;

        if (unlikely(!PCH_GBE_DESC_UNUSED(tx_ring))) {
                netif_stop_queue(netdev);
                netdev_dbg(netdev,
                           "Return : BUSY  next_to use : 0x%08x  next_to clean : 0x%08x\n",
                           tx_ring->next_to_use, tx_ring->next_to_clean);
                return NETDEV_TX_BUSY;
        }

        /* CRC,ITAG no support */
        pch_gbe_tx_queue(adapter, tx_ring, skb);
        return NETDEV_TX_OK;
}

/**
 * pch_gbe_set_multi - Multicast and Promiscuous mode set
 * @netdev:   Network interface device structure
 */
static void pch_gbe_set_multi(struct net_device *netdev)
{
        struct pch_gbe_adapter *adapter = netdev_priv(netdev);
        struct pch_gbe_hw *hw = &adapter->hw;
        struct netdev_hw_addr *ha;
        u8 *mta_list;
        u32 rctl;
        int i;
        int mc_count;

        netdev_dbg(netdev, "netdev->flags : 0x%08x\n", netdev->flags);

        /* Check for Promiscuous and All Multicast modes */
        rctl = ioread32(&hw->reg->RX_MODE);
        mc_count = netdev_mc_count(netdev);
        if ((netdev->flags & IFF_PROMISC)) {
                rctl &= ~PCH_GBE_ADD_FIL_EN;
                rctl &= ~PCH_GBE_MLT_FIL_EN;
        } else if ((netdev->flags & IFF_ALLMULTI)) {
                /* all the multicasting receive permissions */
                rctl |= PCH_GBE_ADD_FIL_EN;
                rctl &= ~PCH_GBE_MLT_FIL_EN;
        } else {
                if (mc_count >= PCH_GBE_MAR_ENTRIES) {
                        /* all the multicasting receive permissions */
                        rctl |= PCH_GBE_ADD_FIL_EN;
                        rctl &= ~PCH_GBE_MLT_FIL_EN;
                } else {
                        rctl |= (PCH_GBE_ADD_FIL_EN | PCH_GBE_MLT_FIL_EN);
                }
        }
        iowrite32(rctl, &hw->reg->RX_MODE);

        if (mc_count >= PCH_GBE_MAR_ENTRIES)
                return;
        mta_list = kmalloc(mc_count * ETH_ALEN, GFP_ATOMIC);
        if (!mta_list)
                return;

        /* The shared function expects a packed array of only addresses. */
        i = 0;
        netdev_for_each_mc_addr(ha, netdev) {
                if (i == mc_count)
                        break;
                memcpy(mta_list + (i++ * ETH_ALEN), &ha->addr, ETH_ALEN);
        }
        pch_gbe_mac_mc_addr_list_update(hw, mta_list, i, 1,
                                        PCH_GBE_MAR_ENTRIES);
        kfree(mta_list);

        netdev_dbg(netdev,
                 "RX_MODE reg(check bit31,30 ADD,MLT) : 0x%08x  netdev->mc_count : 0x%08x\n",
                 ioread32(&hw->reg->RX_MODE), mc_count);
}

/**
 * pch_gbe_set_mac - Change the Ethernet Address of the NIC
 * @netdev: Network interface device structure
 * @addr:   Pointer to an address structure
 * Returns:
 *      0:              Successfully
 *      -EADDRNOTAVAIL: Failed
 */
static int pch_gbe_set_mac(struct net_device *netdev, void *addr)
{
        struct pch_gbe_adapter *adapter = netdev_priv(netdev);
        struct sockaddr *skaddr = addr;
        int ret_val;

        if (!is_valid_ether_addr(skaddr->sa_data)) {
                ret_val = -EADDRNOTAVAIL;
        } else {
                memcpy(netdev->dev_addr, skaddr->sa_data, netdev->addr_len);
                memcpy(adapter->hw.mac.addr, skaddr->sa_data, netdev->addr_len);
                pch_gbe_mac_mar_set(&adapter->hw, adapter->hw.mac.addr, 0);
                ret_val = 0;
        }
        netdev_dbg(netdev, "ret_val : 0x%08x\n", ret_val);
        netdev_dbg(netdev, "dev_addr : %pM\n", netdev->dev_addr);
        netdev_dbg(netdev, "mac_addr : %pM\n", adapter->hw.mac.addr);
        netdev_dbg(netdev, "MAC_ADR1AB reg : 0x%08x 0x%08x\n",
                   ioread32(&adapter->hw.reg->mac_adr[0].high),
                   ioread32(&adapter->hw.reg->mac_adr[0].low));
        return ret_val;
}

/**
 * pch_gbe_change_mtu - Change the Maximum Transfer Unit
 * @netdev:   Network interface device structure
 * @new_mtu:  New value for maximum frame size
 * Returns:
 *      0:              Successfully
 *      -EINVAL:        Failed
 */
static int pch_gbe_change_mtu(struct net_device *netdev, int new_mtu)
{
        struct pch_gbe_adapter *adapter = netdev_priv(netdev);
        int max_frame = new_mtu + ETH_HLEN + ETH_FCS_LEN;
        unsigned long old_rx_buffer_len = adapter->rx_buffer_len;
        int err;

        if (max_frame <= PCH_GBE_FRAME_SIZE_2048)
                adapter->rx_buffer_len = PCH_GBE_FRAME_SIZE_2048;
        else if (max_frame <= PCH_GBE_FRAME_SIZE_4096)
                adapter->rx_buffer_len = PCH_GBE_FRAME_SIZE_4096;
        else if (max_frame <= PCH_GBE_FRAME_SIZE_8192)
                adapter->rx_buffer_len = PCH_GBE_FRAME_SIZE_8192;
        else
                adapter->rx_buffer_len = PCH_GBE_MAX_RX_BUFFER_SIZE;

        if (netif_running(netdev)) {
                pch_gbe_down(adapter);
                err = pch_gbe_up(adapter);
                if (err) {
                        adapter->rx_buffer_len = old_rx_buffer_len;
                        pch_gbe_up(adapter);
                        return err;
                } else {
                        netdev->mtu = new_mtu;
                        adapter->hw.mac.max_frame_size = max_frame;
                }
        } else {
                pch_gbe_reset(adapter);
                netdev->mtu = new_mtu;
                adapter->hw.mac.max_frame_size = max_frame;
        }

        netdev_dbg(netdev,
                   "max_frame : %d  rx_buffer_len : %d  mtu : %d  max_frame_size : %d\n",
                   max_frame, (u32) adapter->rx_buffer_len, netdev->mtu,
                   adapter->hw.mac.max_frame_size);
        return 0;
}

/**
 * pch_gbe_set_features - Reset device after features changed
 * @netdev:   Network interface device structure
 * @features:  New features
 * Returns:
 *      0:              HW state updated successfully
 */
static int pch_gbe_set_features(struct net_device *netdev,
        netdev_features_t features)
{
        struct pch_gbe_adapter *adapter = netdev_priv(netdev);
        netdev_features_t changed = features ^ netdev->features;

        if (!(changed & NETIF_F_RXCSUM))
                return 0;

        if (netif_running(netdev))
                pch_gbe_reinit_locked(adapter);
        else
                pch_gbe_reset(adapter);

        return 0;
}

/**
 * pch_gbe_ioctl - Controls register through a MII interface
 * @netdev:   Network interface device structure
 * @ifr:      Pointer to ifr structure
 * @cmd:      Control command
 * Returns:
 *      0:      Successfully
 *      Negative value: Failed
 */
static int pch_gbe_ioctl(struct net_device *netdev, struct ifreq *ifr, int cmd)
{
        struct pch_gbe_adapter *adapter = netdev_priv(netdev);

        netdev_dbg(netdev, "cmd : 0x%04x\n", cmd);

        if (cmd == SIOCSHWTSTAMP)
                return hwtstamp_ioctl(netdev, ifr, cmd);

        return generic_mii_ioctl(&adapter->mii, if_mii(ifr), cmd, NULL);
}

/**
 * pch_gbe_tx_timeout - Respond to a Tx Hang
 * @netdev:   Network interface device structure
 */
static void pch_gbe_tx_timeout(struct net_device *netdev)
{
        struct pch_gbe_adapter *adapter = netdev_priv(netdev);

        /* Do the reset outside of interrupt context */
        adapter->stats.tx_timeout_count++;
        schedule_work(&adapter->reset_task);
}

/**
 * pch_gbe_napi_poll - NAPI receive and transfer polling callback
 * @napi:    Pointer of polling device struct
 * @budget:  The maximum number of a packet
 * Returns:
 *      false:  Exit the polling mode
 *      true:   Continue the polling mode
 */
static int pch_gbe_napi_poll(struct napi_struct *napi, int budget)
{
        struct pch_gbe_adapter *adapter =
            container_of(napi, struct pch_gbe_adapter, napi);
        int work_done = 0;
        bool poll_end_flag = false;
        bool cleaned = false;

        netdev_dbg(adapter->netdev, "budget : %d\n", budget);

        pch_gbe_clean_rx(adapter, adapter->rx_ring, &work_done, budget);
        cleaned = pch_gbe_clean_tx(adapter, adapter->tx_ring);

        if (cleaned)
                work_done = budget;
        /* If no Tx and not enough Rx work done,
         * exit the polling mode
         */
        if (work_done < budget)
                poll_end_flag = true;

        if (poll_end_flag) {
                napi_complete_done(napi, work_done);
                pch_gbe_irq_enable(adapter);
        }

        if (adapter->rx_stop_flag) {
                adapter->rx_stop_flag = false;
                pch_gbe_enable_dma_rx(&adapter->hw);
        }

        netdev_dbg(adapter->netdev,
                   "poll_end_flag : %d  work_done : %d  budget : %d\n",
                   poll_end_flag, work_done, budget);

        return work_done;
}

#ifdef CONFIG_NET_POLL_CONTROLLER
/**
 * pch_gbe_netpoll - Used by things like netconsole to send skbs
 * @netdev:  Network interface device structure
 */
static void pch_gbe_netpoll(struct net_device *netdev)
{
        struct pch_gbe_adapter *adapter = netdev_priv(netdev);

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

static const struct net_device_ops pch_gbe_netdev_ops = {
        .ndo_open = pch_gbe_open,
        .ndo_stop = pch_gbe_stop,
        .ndo_start_xmit = pch_gbe_xmit_frame,
        .ndo_set_mac_address = pch_gbe_set_mac,
        .ndo_tx_timeout = pch_gbe_tx_timeout,
        .ndo_change_mtu = pch_gbe_change_mtu,
        .ndo_set_features = pch_gbe_set_features,
        .ndo_do_ioctl = pch_gbe_ioctl,
        .ndo_set_rx_mode = pch_gbe_set_multi,
#ifdef CONFIG_NET_POLL_CONTROLLER
        .ndo_poll_controller = pch_gbe_netpoll,
#endif
};

static pci_ers_result_t pch_gbe_io_error_detected(struct pci_dev *pdev,
                                                pci_channel_state_t state)
{
        struct net_device *netdev = pci_get_drvdata(pdev);
        struct pch_gbe_adapter *adapter = netdev_priv(netdev);

        netif_device_detach(netdev);
        if (netif_running(netdev))
                pch_gbe_down(adapter);
        pci_disable_device(pdev);
        /* Request a slot slot reset. */
        return PCI_ERS_RESULT_NEED_RESET;
}

static pci_ers_result_t pch_gbe_io_slot_reset(struct pci_dev *pdev)
{
        struct net_device *netdev = pci_get_drvdata(pdev);
        struct pch_gbe_adapter *adapter = netdev_priv(netdev);
        struct pch_gbe_hw *hw = &adapter->hw;

        if (pci_enable_device(pdev)) {
                netdev_err(netdev, "Cannot re-enable PCI device after reset\n");
                return PCI_ERS_RESULT_DISCONNECT;
        }
        pci_set_master(pdev);
        pci_enable_wake(pdev, PCI_D0, 0);
        pch_gbe_hal_power_up_phy(hw);
        pch_gbe_reset(adapter);
        /* Clear wake up status */
        pch_gbe_mac_set_wol_event(hw, 0);

        return PCI_ERS_RESULT_RECOVERED;
}

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

        if (netif_running(netdev)) {
                if (pch_gbe_up(adapter)) {
                        netdev_dbg(netdev,
                                   "can't bring device back up after reset\n");
                        return;
                }
        }
        netif_device_attach(netdev);
}

static int __pch_gbe_suspend(struct pci_dev *pdev)
{
        struct net_device *netdev = pci_get_drvdata(pdev);
        struct pch_gbe_adapter *adapter = netdev_priv(netdev);
        struct pch_gbe_hw *hw = &adapter->hw;
        u32 wufc = adapter->wake_up_evt;
        int retval = 0;

        netif_device_detach(netdev);
        if (netif_running(netdev))
                pch_gbe_down(adapter);
        if (wufc) {
                pch_gbe_set_multi(netdev);
                pch_gbe_setup_rctl(adapter);
                pch_gbe_configure_rx(adapter);
                pch_gbe_set_rgmii_ctrl(adapter, hw->mac.link_speed,
                                        hw->mac.link_duplex);
                pch_gbe_set_mode(adapter, hw->mac.link_speed,
                                        hw->mac.link_duplex);
                pch_gbe_mac_set_wol_event(hw, wufc);
                pci_disable_device(pdev);
        } else {
                pch_gbe_hal_power_down_phy(hw);
                pch_gbe_mac_set_wol_event(hw, wufc);
                pci_disable_device(pdev);
        }
        return retval;
}

#ifdef CONFIG_PM
static int pch_gbe_suspend(struct device *device)
{
        struct pci_dev *pdev = to_pci_dev(device);

        return __pch_gbe_suspend(pdev);
}

static int pch_gbe_resume(struct device *device)
{
        struct pci_dev *pdev = to_pci_dev(device);
        struct net_device *netdev = pci_get_drvdata(pdev);
        struct pch_gbe_adapter *adapter = netdev_priv(netdev);
        struct pch_gbe_hw *hw = &adapter->hw;
        u32 err;

        err = pci_enable_device(pdev);
        if (err) {
                netdev_err(netdev, "Cannot enable PCI device from suspend\n");
                return err;
        }
        pci_set_master(pdev);
        pch_gbe_hal_power_up_phy(hw);
        pch_gbe_reset(adapter);
        /* Clear wake on lan control and status */
        pch_gbe_mac_set_wol_event(hw, 0);

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

        return 0;
}
#endif /* CONFIG_PM */

static void pch_gbe_shutdown(struct pci_dev *pdev)
{
        __pch_gbe_suspend(pdev);
        if (system_state == SYSTEM_POWER_OFF) {
                pci_wake_from_d3(pdev, true);
                pci_set_power_state(pdev, PCI_D3hot);
        }
}

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

        cancel_work_sync(&adapter->reset_task);
        unregister_netdev(netdev);

        pch_gbe_hal_phy_hw_reset(&adapter->hw);

        free_netdev(netdev);
}

static int pch_gbe_probe(struct pci_dev *pdev,
                          const struct pci_device_id *pci_id)
{
        struct net_device *netdev;
        struct pch_gbe_adapter *adapter;
        int ret;

        ret = pcim_enable_device(pdev);
        if (ret)
                return ret;

        if (pci_set_dma_mask(pdev, DMA_BIT_MASK(64))
                || pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(64))) {
                ret = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
                if (ret) {
                        ret = pci_set_consistent_dma_mask(pdev,
                                                          DMA_BIT_MASK(32));
                        if (ret) {
                                dev_err(&pdev->dev, "ERR: No usable DMA "
                                        "configuration, aborting\n");
                                return ret;
                        }
                }
        }

        ret = pcim_iomap_regions(pdev, 1 << PCH_GBE_PCI_BAR, pci_name(pdev));
        if (ret) {
                dev_err(&pdev->dev,
                        "ERR: Can't reserve PCI I/O and memory resources\n");
                return ret;
        }
        pci_set_master(pdev);

        netdev = alloc_etherdev((int)sizeof(struct pch_gbe_adapter));
        if (!netdev)
                return -ENOMEM;
        SET_NETDEV_DEV(netdev, &pdev->dev);

        pci_set_drvdata(pdev, netdev);
        adapter = netdev_priv(netdev);
        adapter->netdev = netdev;
        adapter->pdev = pdev;
        adapter->hw.back = adapter;
        adapter->hw.reg = pcim_iomap_table(pdev)[PCH_GBE_PCI_BAR];
        adapter->pdata = (struct pch_gbe_privdata *)pci_id->driver_data;
        if (adapter->pdata && adapter->pdata->platform_init)
                adapter->pdata->platform_init(pdev);

        adapter->ptp_pdev = pci_get_bus_and_slot(adapter->pdev->bus->number,
                                               PCI_DEVFN(12, 4));

        netdev->netdev_ops = &pch_gbe_netdev_ops;
        netdev->watchdog_timeo = PCH_GBE_WATCHDOG_PERIOD;
        netif_napi_add(netdev, &adapter->napi,
                       pch_gbe_napi_poll, PCH_GBE_RX_WEIGHT);
        netdev->hw_features = NETIF_F_RXCSUM |
                NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM;
        netdev->features = netdev->hw_features;
        pch_gbe_set_ethtool_ops(netdev);

        /* MTU range: 46 - 10300 */
        netdev->min_mtu = ETH_ZLEN - ETH_HLEN;
        netdev->max_mtu = PCH_GBE_MAX_JUMBO_FRAME_SIZE -
                          (ETH_HLEN + ETH_FCS_LEN);

        pch_gbe_mac_load_mac_addr(&adapter->hw);
        pch_gbe_mac_reset_hw(&adapter->hw);

        /* setup the private structure */
        ret = pch_gbe_sw_init(adapter);
        if (ret)
                goto err_free_netdev;

        /* Initialize PHY */
        ret = pch_gbe_init_phy(adapter);
        if (ret) {
                dev_err(&pdev->dev, "PHY initialize error\n");
                goto err_free_adapter;
        }
        pch_gbe_hal_get_bus_info(&adapter->hw);

        /* Read the MAC address. and store to the private data */
        ret = pch_gbe_hal_read_mac_addr(&adapter->hw);
        if (ret) {
                dev_err(&pdev->dev, "MAC address Read Error\n");
                goto err_free_adapter;
        }

        memcpy(netdev->dev_addr, adapter->hw.mac.addr, netdev->addr_len);
        if (!is_valid_ether_addr(netdev->dev_addr)) {
                /*
                 * If the MAC is invalid (or just missing), display a warning
                 * but do not abort setting up the device. pch_gbe_up will
                 * prevent the interface from being brought up until a valid MAC
                 * is set.
                 */
                dev_err(&pdev->dev, "Invalid MAC address, "
                                    "interface disabled.\n");
        }
        setup_timer(&adapter->watchdog_timer, pch_gbe_watchdog,
                    (unsigned long)adapter);

        INIT_WORK(&adapter->reset_task, pch_gbe_reset_task);

        pch_gbe_check_options(adapter);

        /* initialize the wol settings based on the eeprom settings */
        adapter->wake_up_evt = PCH_GBE_WL_INIT_SETTING;
        dev_info(&pdev->dev, "MAC address : %pM\n", netdev->dev_addr);

        /* reset the hardware with the new settings */
        pch_gbe_reset(adapter);

        ret = register_netdev(netdev);
        if (ret)
                goto err_free_adapter;
        /* tell the stack to leave us alone until pch_gbe_open() is called */
        netif_carrier_off(netdev);
        netif_stop_queue(netdev);

        dev_dbg(&pdev->dev, "PCH Network Connection\n");

        /* Disable hibernation on certain platforms */
        if (adapter->pdata && adapter->pdata->phy_disable_hibernate)
                pch_gbe_phy_disable_hibernate(&adapter->hw);

        device_set_wakeup_enable(&pdev->dev, 1);
        return 0;

err_free_adapter:
        pch_gbe_hal_phy_hw_reset(&adapter->hw);
err_free_netdev:
        free_netdev(netdev);
        return ret;
}

/* The AR803X PHY on the MinnowBoard requires a physical pin to be toggled to
 * ensure it is awake for probe and init. Request the line and reset the PHY.
 */
static int pch_gbe_minnow_platform_init(struct pci_dev *pdev)
{
        unsigned long flags = GPIOF_DIR_OUT | GPIOF_INIT_HIGH | GPIOF_EXPORT;
        unsigned gpio = MINNOW_PHY_RESET_GPIO;
        int ret;

        ret = devm_gpio_request_one(&pdev->dev, gpio, flags,
                                    "minnow_phy_reset");
        if (ret) {
                dev_err(&pdev->dev,
                        "ERR: Can't request PHY reset GPIO line '%d'\n", gpio);
                return ret;
        }

        gpio_set_value(gpio, 0);
        usleep_range(1250, 1500);
        gpio_set_value(gpio, 1);
        usleep_range(1250, 1500);

        return ret;
}

static struct pch_gbe_privdata pch_gbe_minnow_privdata = {
        .phy_tx_clk_delay = true,
        .phy_disable_hibernate = true,
        .platform_init = pch_gbe_minnow_platform_init,
};

static const struct pci_device_id pch_gbe_pcidev_id[] = {
        {.vendor = PCI_VENDOR_ID_INTEL,
         .device = PCI_DEVICE_ID_INTEL_IOH1_GBE,
         .subvendor = PCI_VENDOR_ID_CIRCUITCO,
         .subdevice = PCI_SUBSYSTEM_ID_CIRCUITCO_MINNOWBOARD,
         .class = (PCI_CLASS_NETWORK_ETHERNET << 8),
         .class_mask = (0xFFFF00),
         .driver_data = (kernel_ulong_t)&pch_gbe_minnow_privdata
         },
        {.vendor = PCI_VENDOR_ID_INTEL,
         .device = PCI_DEVICE_ID_INTEL_IOH1_GBE,
         .subvendor = PCI_ANY_ID,
         .subdevice = PCI_ANY_ID,
         .class = (PCI_CLASS_NETWORK_ETHERNET << 8),
         .class_mask = (0xFFFF00)
         },
        {.vendor = PCI_VENDOR_ID_ROHM,
         .device = PCI_DEVICE_ID_ROHM_ML7223_GBE,
         .subvendor = PCI_ANY_ID,
         .subdevice = PCI_ANY_ID,
         .class = (PCI_CLASS_NETWORK_ETHERNET << 8),
         .class_mask = (0xFFFF00)
         },
        {.vendor = PCI_VENDOR_ID_ROHM,
         .device = PCI_DEVICE_ID_ROHM_ML7831_GBE,
         .subvendor = PCI_ANY_ID,
         .subdevice = PCI_ANY_ID,
         .class = (PCI_CLASS_NETWORK_ETHERNET << 8),
         .class_mask = (0xFFFF00)
         },
        /* required last entry */
        {0}
};

#ifdef CONFIG_PM
static const struct dev_pm_ops pch_gbe_pm_ops = {
        .suspend = pch_gbe_suspend,
        .resume = pch_gbe_resume,
        .freeze = pch_gbe_suspend,
        .thaw = pch_gbe_resume,
        .poweroff = pch_gbe_suspend,
        .restore = pch_gbe_resume,
};
#endif

static const struct pci_error_handlers pch_gbe_err_handler = {
        .error_detected = pch_gbe_io_error_detected,
        .slot_reset = pch_gbe_io_slot_reset,
        .resume = pch_gbe_io_resume
};

static struct pci_driver pch_gbe_driver = {
        .name = KBUILD_MODNAME,
        .id_table = pch_gbe_pcidev_id,
        .probe = pch_gbe_probe,
        .remove = pch_gbe_remove,
#ifdef CONFIG_PM
        .driver.pm = &pch_gbe_pm_ops,
#endif
        .shutdown = pch_gbe_shutdown,
        .err_handler = &pch_gbe_err_handler
};


static int __init pch_gbe_init_module(void)
{
        int ret;

        pr_info("EG20T PCH Gigabit Ethernet Driver - version %s\n",DRV_VERSION);
        ret = pci_register_driver(&pch_gbe_driver);
        if (copybreak != PCH_GBE_COPYBREAK_DEFAULT) {
                if (copybreak == 0) {
                        pr_info("copybreak disabled\n");
                } else {
                        pr_info("copybreak enabled for packets <= %u bytes\n",
                                copybreak);
                }
        }
        return ret;
}

static void __exit pch_gbe_exit_module(void)
{
        pci_unregister_driver(&pch_gbe_driver);
}

module_init(pch_gbe_init_module);
module_exit(pch_gbe_exit_module);

MODULE_DESCRIPTION("EG20T PCH Gigabit ethernet Driver");
MODULE_AUTHOR("LAPIS SEMICONDUCTOR, <tshimizu818@gmail.com>");
MODULE_LICENSE("GPL");
MODULE_VERSION(DRV_VERSION);
MODULE_DEVICE_TABLE(pci, pch_gbe_pcidev_id);

module_param(copybreak, uint, 0644);
MODULE_PARM_DESC(copybreak,
        "Maximum size of packet that is copied to a new buffer on receive");

/* pch_gbe_main.c */