/*
 * New driver for Marvell Yukon 2 chipset.
 * Based on earlier sk98lin, and skge driver.
 *
 * This driver intentionally does not support all the features
 * of the original driver such as link fail-over and link management because
 * those should be done at higher levels.
 *
 * Copyright (C) 2005 Stephen Hemminger <shemminger@osdl.org>
 *
 * 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; either 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, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/crc32.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/dma-mapping.h>
#include <linux/etherdevice.h>
#include <linux/ethtool.h>
#include <linux/pci.h>
#include <linux/ip.h>
#include <linux/slab.h>
#include <net/ip.h>
#include <linux/tcp.h>
#include <linux/in.h>
#include <linux/delay.h>
#include <linux/workqueue.h>
#include <linux/if_vlan.h>
#include <linux/prefetch.h>
#include <linux/debugfs.h>
#include <linux/mii.h>

#include <asm/irq.h>

#include "sky2.h"

#define DRV_NAME                "sky2"
#define DRV_VERSION             "1.28"

/*
 * The Yukon II chipset takes 64 bit command blocks (called list elements)
 * that are organized into three (receive, transmit, status) different rings
 * similar to Tigon3.
 */

#define RX_LE_SIZE              1024
#define RX_LE_BYTES             (RX_LE_SIZE*sizeof(struct sky2_rx_le))
#define RX_MAX_PENDING          (RX_LE_SIZE/6 - 2)
#define RX_DEF_PENDING          RX_MAX_PENDING

/* This is the worst case number of transmit list elements for a single skb:
   VLAN:GSO + CKSUM + Data + skb_frags * DMA */
#define MAX_SKB_TX_LE   (2 + (sizeof(dma_addr_t)/sizeof(u32))*(MAX_SKB_FRAGS+1))
#define TX_MIN_PENDING          (MAX_SKB_TX_LE+1)
#define TX_MAX_PENDING          1024
#define TX_DEF_PENDING          127

#define TX_WATCHDOG             (5 * HZ)
#define NAPI_WEIGHT             64
#define PHY_RETRIES             1000

#define SKY2_EEPROM_MAGIC       0x9955aabb

#define RING_NEXT(x, s) (((x)+1) & ((s)-1))

static const u32 default_msg =
    NETIF_MSG_DRV | NETIF_MSG_PROBE | NETIF_MSG_LINK
    | NETIF_MSG_TIMER | NETIF_MSG_TX_ERR | NETIF_MSG_RX_ERR
    | NETIF_MSG_IFUP | NETIF_MSG_IFDOWN;

static int debug = -1;          /* defaults above */
module_param(debug, int, 0);
MODULE_PARM_DESC(debug, "Debug level (0=none,...,16=all)");

static int copybreak __read_mostly = 128;
module_param(copybreak, int, 0);
MODULE_PARM_DESC(copybreak, "Receive copy threshold");

static int disable_msi = 0;
module_param(disable_msi, int, 0);
MODULE_PARM_DESC(disable_msi, "Disable Message Signaled Interrupt (MSI)");

static DEFINE_PCI_DEVICE_TABLE(sky2_id_table) = {
        { PCI_DEVICE(PCI_VENDOR_ID_SYSKONNECT, 0x9000) }, /* SK-9Sxx */
        { PCI_DEVICE(PCI_VENDOR_ID_SYSKONNECT, 0x9E00) }, /* SK-9Exx */
        { PCI_DEVICE(PCI_VENDOR_ID_SYSKONNECT, 0x9E01) }, /* SK-9E21M */
        { PCI_DEVICE(PCI_VENDOR_ID_DLINK, 0x4b00) },    /* DGE-560T */
        { PCI_DEVICE(PCI_VENDOR_ID_DLINK, 0x4001) },    /* DGE-550SX */
        { PCI_DEVICE(PCI_VENDOR_ID_DLINK, 0x4B02) },    /* DGE-560SX */
        { PCI_DEVICE(PCI_VENDOR_ID_DLINK, 0x4B03) },    /* DGE-550T */
        { PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x4340) }, /* 88E8021 */
        { PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x4341) }, /* 88E8022 */
        { PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x4342) }, /* 88E8061 */
        { PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x4343) }, /* 88E8062 */
        { PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x4344) }, /* 88E8021 */
        { PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x4345) }, /* 88E8022 */
        { PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x4346) }, /* 88E8061 */
        { PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x4347) }, /* 88E8062 */
        { PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x4350) }, /* 88E8035 */
        { PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x4351) }, /* 88E8036 */
        { PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x4352) }, /* 88E8038 */
        { PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x4353) }, /* 88E8039 */
        { PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x4354) }, /* 88E8040 */
        { PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x4355) }, /* 88E8040T */
        { PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x4356) }, /* 88EC033 */
        { PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x4357) }, /* 88E8042 */
        { PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x435A) }, /* 88E8048 */
        { PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x4360) }, /* 88E8052 */
        { PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x4361) }, /* 88E8050 */
        { PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x4362) }, /* 88E8053 */
        { PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x4363) }, /* 88E8055 */
        { PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x4364) }, /* 88E8056 */
        { PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x4365) }, /* 88E8070 */
        { PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x4366) }, /* 88EC036 */
        { PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x4367) }, /* 88EC032 */
        { PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x4368) }, /* 88EC034 */
        { PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x4369) }, /* 88EC042 */
        { PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x436A) }, /* 88E8058 */
        { PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x436B) }, /* 88E8071 */
        { PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x436C) }, /* 88E8072 */
        { PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x436D) }, /* 88E8055 */
        { PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x4370) }, /* 88E8075 */
        { PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x4380) }, /* 88E8057 */
        { PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x4381) }, /* 88E8059 */
        { 0 }
};

MODULE_DEVICE_TABLE(pci, sky2_id_table);

/* Avoid conditionals by using array */
static const unsigned txqaddr[] = { Q_XA1, Q_XA2 };
static const unsigned rxqaddr[] = { Q_R1, Q_R2 };
static const u32 portirq_msk[] = { Y2_IS_PORT_1, Y2_IS_PORT_2 };

static void sky2_set_multicast(struct net_device *dev);

/* Access to PHY via serial interconnect */
static int gm_phy_write(struct sky2_hw *hw, unsigned port, u16 reg, u16 val)
{
        int i;

        gma_write16(hw, port, GM_SMI_DATA, val);
        gma_write16(hw, port, GM_SMI_CTRL,
                    GM_SMI_CT_PHY_AD(PHY_ADDR_MARV) | GM_SMI_CT_REG_AD(reg));

        for (i = 0; i < PHY_RETRIES; i++) {
                u16 ctrl = gma_read16(hw, port, GM_SMI_CTRL);
                if (ctrl == 0xffff)
                        goto io_error;

                if (!(ctrl & GM_SMI_CT_BUSY))
                        return 0;

                udelay(10);
        }

        dev_warn(&hw->pdev->dev, "%s: phy write timeout\n", hw->dev[port]->name);
        return -ETIMEDOUT;

io_error:
        dev_err(&hw->pdev->dev, "%s: phy I/O error\n", hw->dev[port]->name);
        return -EIO;
}

static int __gm_phy_read(struct sky2_hw *hw, unsigned port, u16 reg, u16 *val)
{
        int i;

        gma_write16(hw, port, GM_SMI_CTRL, GM_SMI_CT_PHY_AD(PHY_ADDR_MARV)
                    | GM_SMI_CT_REG_AD(reg) | GM_SMI_CT_OP_RD);

        for (i = 0; i < PHY_RETRIES; i++) {
                u16 ctrl = gma_read16(hw, port, GM_SMI_CTRL);
                if (ctrl == 0xffff)
                        goto io_error;

                if (ctrl & GM_SMI_CT_RD_VAL) {
                        *val = gma_read16(hw, port, GM_SMI_DATA);
                        return 0;
                }

                udelay(10);
        }

        dev_warn(&hw->pdev->dev, "%s: phy read timeout\n", hw->dev[port]->name);
        return -ETIMEDOUT;
io_error:
        dev_err(&hw->pdev->dev, "%s: phy I/O error\n", hw->dev[port]->name);
        return -EIO;
}

static inline u16 gm_phy_read(struct sky2_hw *hw, unsigned port, u16 reg)
{
        u16 v;
        __gm_phy_read(hw, port, reg, &v);
        return v;
}


static void sky2_power_on(struct sky2_hw *hw)
{
        /* switch power to VCC (WA for VAUX problem) */
        sky2_write8(hw, B0_POWER_CTRL,
                    PC_VAUX_ENA | PC_VCC_ENA | PC_VAUX_OFF | PC_VCC_ON);

        /* disable Core Clock Division, */
        sky2_write32(hw, B2_Y2_CLK_CTRL, Y2_CLK_DIV_DIS);

        if (hw->chip_id == CHIP_ID_YUKON_XL && hw->chip_rev > CHIP_REV_YU_XL_A1)
                /* enable bits are inverted */
                sky2_write8(hw, B2_Y2_CLK_GATE,
                            Y2_PCI_CLK_LNK1_DIS | Y2_COR_CLK_LNK1_DIS |
                            Y2_CLK_GAT_LNK1_DIS | Y2_PCI_CLK_LNK2_DIS |
                            Y2_COR_CLK_LNK2_DIS | Y2_CLK_GAT_LNK2_DIS);
        else
                sky2_write8(hw, B2_Y2_CLK_GATE, 0);

        if (hw->flags & SKY2_HW_ADV_POWER_CTL) {
                u32 reg;

                sky2_pci_write32(hw, PCI_DEV_REG3, 0);

                reg = sky2_pci_read32(hw, PCI_DEV_REG4);
                /* set all bits to 0 except bits 15..12 and 8 */
                reg &= P_ASPM_CONTROL_MSK;
                sky2_pci_write32(hw, PCI_DEV_REG4, reg);

                reg = sky2_pci_read32(hw, PCI_DEV_REG5);
                /* set all bits to 0 except bits 28 & 27 */
                reg &= P_CTL_TIM_VMAIN_AV_MSK;
                sky2_pci_write32(hw, PCI_DEV_REG5, reg);

                sky2_pci_write32(hw, PCI_CFG_REG_1, 0);

                sky2_write16(hw, B0_CTST, Y2_HW_WOL_ON);

                /* Enable workaround for dev 4.107 on Yukon-Ultra & Extreme */
                reg = sky2_read32(hw, B2_GP_IO);
                reg |= GLB_GPIO_STAT_RACE_DIS;
                sky2_write32(hw, B2_GP_IO, reg);

                sky2_read32(hw, B2_GP_IO);
        }

        /* Turn on "driver loaded" LED */
        sky2_write16(hw, B0_CTST, Y2_LED_STAT_ON);
}

static void sky2_power_aux(struct sky2_hw *hw)
{
        if (hw->chip_id == CHIP_ID_YUKON_XL && hw->chip_rev > CHIP_REV_YU_XL_A1)
                sky2_write8(hw, B2_Y2_CLK_GATE, 0);
        else
                /* enable bits are inverted */
                sky2_write8(hw, B2_Y2_CLK_GATE,
                            Y2_PCI_CLK_LNK1_DIS | Y2_COR_CLK_LNK1_DIS |
                            Y2_CLK_GAT_LNK1_DIS | Y2_PCI_CLK_LNK2_DIS |
                            Y2_COR_CLK_LNK2_DIS | Y2_CLK_GAT_LNK2_DIS);

        /* switch power to VAUX if supported and PME from D3cold */
        if ( (sky2_read32(hw, B0_CTST) & Y2_VAUX_AVAIL) &&
             pci_pme_capable(hw->pdev, PCI_D3cold))
                sky2_write8(hw, B0_POWER_CTRL,
                            (PC_VAUX_ENA | PC_VCC_ENA |
                             PC_VAUX_ON | PC_VCC_OFF));

        /* turn off "driver loaded LED" */
        sky2_write16(hw, B0_CTST, Y2_LED_STAT_OFF);
}

static void sky2_gmac_reset(struct sky2_hw *hw, unsigned port)
{
        u16 reg;

        /* disable all GMAC IRQ's */
        sky2_write8(hw, SK_REG(port, GMAC_IRQ_MSK), 0);

        gma_write16(hw, port, GM_MC_ADDR_H1, 0);        /* clear MC hash */
        gma_write16(hw, port, GM_MC_ADDR_H2, 0);
        gma_write16(hw, port, GM_MC_ADDR_H3, 0);
        gma_write16(hw, port, GM_MC_ADDR_H4, 0);

        reg = gma_read16(hw, port, GM_RX_CTRL);
        reg |= GM_RXCR_UCF_ENA | GM_RXCR_MCF_ENA;
        gma_write16(hw, port, GM_RX_CTRL, reg);
}

/* flow control to advertise bits */
static const u16 copper_fc_adv[] = {
        [FC_NONE]       = 0,
        [FC_TX]         = PHY_M_AN_ASP,
        [FC_RX]         = PHY_M_AN_PC,
        [FC_BOTH]       = PHY_M_AN_PC | PHY_M_AN_ASP,
};

/* flow control to advertise bits when using 1000BaseX */
static const u16 fiber_fc_adv[] = {
        [FC_NONE] = PHY_M_P_NO_PAUSE_X,
        [FC_TX]   = PHY_M_P_ASYM_MD_X,
        [FC_RX]   = PHY_M_P_SYM_MD_X,
        [FC_BOTH] = PHY_M_P_BOTH_MD_X,
};

/* flow control to GMA disable bits */
static const u16 gm_fc_disable[] = {
        [FC_NONE] = GM_GPCR_FC_RX_DIS | GM_GPCR_FC_TX_DIS,
        [FC_TX]   = GM_GPCR_FC_RX_DIS,
        [FC_RX]   = GM_GPCR_FC_TX_DIS,
        [FC_BOTH] = 0,
};


static void sky2_phy_init(struct sky2_hw *hw, unsigned port)
{
        struct sky2_port *sky2 = netdev_priv(hw->dev[port]);
        u16 ctrl, ct1000, adv, pg, ledctrl, ledover, reg;

        if ( (sky2->flags & SKY2_FLAG_AUTO_SPEED) &&
            !(hw->flags & SKY2_HW_NEWER_PHY)) {
                u16 ectrl = gm_phy_read(hw, port, PHY_MARV_EXT_CTRL);

                ectrl &= ~(PHY_M_EC_M_DSC_MSK | PHY_M_EC_S_DSC_MSK |
                           PHY_M_EC_MAC_S_MSK);
                ectrl |= PHY_M_EC_MAC_S(MAC_TX_CLK_25_MHZ);

                /* on PHY 88E1040 Rev.D0 (and newer) downshift control changed */
                if (hw->chip_id == CHIP_ID_YUKON_EC)
                        /* set downshift counter to 3x and enable downshift */
                        ectrl |= PHY_M_EC_DSC_2(2) | PHY_M_EC_DOWN_S_ENA;
                else
                        /* set master & slave downshift counter to 1x */
                        ectrl |= PHY_M_EC_M_DSC(0) | PHY_M_EC_S_DSC(1);

                gm_phy_write(hw, port, PHY_MARV_EXT_CTRL, ectrl);
        }

        ctrl = gm_phy_read(hw, port, PHY_MARV_PHY_CTRL);
        if (sky2_is_copper(hw)) {
                if (!(hw->flags & SKY2_HW_GIGABIT)) {
                        /* enable automatic crossover */
                        ctrl |= PHY_M_PC_MDI_XMODE(PHY_M_PC_ENA_AUTO) >> 1;

                        if (hw->chip_id == CHIP_ID_YUKON_FE_P &&
                            hw->chip_rev == CHIP_REV_YU_FE2_A0) {
                                u16 spec;

                                /* Enable Class A driver for FE+ A0 */
                                spec = gm_phy_read(hw, port, PHY_MARV_FE_SPEC_2);
                                spec |= PHY_M_FESC_SEL_CL_A;
                                gm_phy_write(hw, port, PHY_MARV_FE_SPEC_2, spec);
                        }
                } else {
                        /* disable energy detect */
                        ctrl &= ~PHY_M_PC_EN_DET_MSK;

                        /* enable automatic crossover */
                        ctrl |= PHY_M_PC_MDI_XMODE(PHY_M_PC_ENA_AUTO);

                        /* downshift on PHY 88E1112 and 88E1149 is changed */
                        if ( (sky2->flags & SKY2_FLAG_AUTO_SPEED) &&
                             (hw->flags & SKY2_HW_NEWER_PHY)) {
                                /* set downshift counter to 3x and enable downshift */
                                ctrl &= ~PHY_M_PC_DSC_MSK;
                                ctrl |= PHY_M_PC_DSC(2) | PHY_M_PC_DOWN_S_ENA;
                        }
                }
        } else {
                /* workaround for deviation #4.88 (CRC errors) */
                /* disable Automatic Crossover */

                ctrl &= ~PHY_M_PC_MDIX_MSK;
        }

        gm_phy_write(hw, port, PHY_MARV_PHY_CTRL, ctrl);

        /* special setup for PHY 88E1112 Fiber */
        if (hw->chip_id == CHIP_ID_YUKON_XL && (hw->flags & SKY2_HW_FIBRE_PHY)) {
                pg = gm_phy_read(hw, port, PHY_MARV_EXT_ADR);

                /* Fiber: select 1000BASE-X only mode MAC Specific Ctrl Reg. */
                gm_phy_write(hw, port, PHY_MARV_EXT_ADR, 2);
                ctrl = gm_phy_read(hw, port, PHY_MARV_PHY_CTRL);
                ctrl &= ~PHY_M_MAC_MD_MSK;
                ctrl |= PHY_M_MAC_MODE_SEL(PHY_M_MAC_MD_1000BX);
                gm_phy_write(hw, port, PHY_MARV_PHY_CTRL, ctrl);

                if (hw->pmd_type  == 'P') {
                        /* select page 1 to access Fiber registers */
                        gm_phy_write(hw, port, PHY_MARV_EXT_ADR, 1);

                        /* for SFP-module set SIGDET polarity to low */
                        ctrl = gm_phy_read(hw, port, PHY_MARV_PHY_CTRL);
                        ctrl |= PHY_M_FIB_SIGD_POL;
                        gm_phy_write(hw, port, PHY_MARV_PHY_CTRL, ctrl);
                }

                gm_phy_write(hw, port, PHY_MARV_EXT_ADR, pg);
        }

        ctrl = PHY_CT_RESET;
        ct1000 = 0;
        adv = PHY_AN_CSMA;
        reg = 0;

        if (sky2->flags & SKY2_FLAG_AUTO_SPEED) {
                if (sky2_is_copper(hw)) {
                        if (sky2->advertising & ADVERTISED_1000baseT_Full)
                                ct1000 |= PHY_M_1000C_AFD;
                        if (sky2->advertising & ADVERTISED_1000baseT_Half)
                                ct1000 |= PHY_M_1000C_AHD;
                        if (sky2->advertising & ADVERTISED_100baseT_Full)
                                adv |= PHY_M_AN_100_FD;
                        if (sky2->advertising & ADVERTISED_100baseT_Half)
                                adv |= PHY_M_AN_100_HD;
                        if (sky2->advertising & ADVERTISED_10baseT_Full)
                                adv |= PHY_M_AN_10_FD;
                        if (sky2->advertising & ADVERTISED_10baseT_Half)
                                adv |= PHY_M_AN_10_HD;

                } else {        /* special defines for FIBER (88E1040S only) */
                        if (sky2->advertising & ADVERTISED_1000baseT_Full)
                                adv |= PHY_M_AN_1000X_AFD;
                        if (sky2->advertising & ADVERTISED_1000baseT_Half)
                                adv |= PHY_M_AN_1000X_AHD;
                }

                /* Restart Auto-negotiation */
                ctrl |= PHY_CT_ANE | PHY_CT_RE_CFG;
        } else {
                /* forced speed/duplex settings */
                ct1000 = PHY_M_1000C_MSE;

                /* Disable auto update for duplex flow control and duplex */
                reg |= GM_GPCR_AU_DUP_DIS | GM_GPCR_AU_SPD_DIS;

                switch (sky2->speed) {
                case SPEED_1000:
                        ctrl |= PHY_CT_SP1000;
                        reg |= GM_GPCR_SPEED_1000;
                        break;
                case SPEED_100:
                        ctrl |= PHY_CT_SP100;
                        reg |= GM_GPCR_SPEED_100;
                        break;
                }

                if (sky2->duplex == DUPLEX_FULL) {
                        reg |= GM_GPCR_DUP_FULL;
                        ctrl |= PHY_CT_DUP_MD;
                } else if (sky2->speed < SPEED_1000)
                        sky2->flow_mode = FC_NONE;
        }

        if (sky2->flags & SKY2_FLAG_AUTO_PAUSE) {
                if (sky2_is_copper(hw))
                        adv |= copper_fc_adv[sky2->flow_mode];
                else
                        adv |= fiber_fc_adv[sky2->flow_mode];
        } else {
                reg |= GM_GPCR_AU_FCT_DIS;
                reg |= gm_fc_disable[sky2->flow_mode];

                /* Forward pause packets to GMAC? */
                if (sky2->flow_mode & FC_RX)
                        sky2_write8(hw, SK_REG(port, GMAC_CTRL), GMC_PAUSE_ON);
                else
                        sky2_write8(hw, SK_REG(port, GMAC_CTRL), GMC_PAUSE_OFF);
        }

        gma_write16(hw, port, GM_GP_CTRL, reg);

        if (hw->flags & SKY2_HW_GIGABIT)
                gm_phy_write(hw, port, PHY_MARV_1000T_CTRL, ct1000);

        gm_phy_write(hw, port, PHY_MARV_AUNE_ADV, adv);
        gm_phy_write(hw, port, PHY_MARV_CTRL, ctrl);

        /* Setup Phy LED's */
        ledctrl = PHY_M_LED_PULS_DUR(PULS_170MS);
        ledover = 0;

        switch (hw->chip_id) {
        case CHIP_ID_YUKON_FE:
                /* on 88E3082 these bits are at 11..9 (shifted left) */
                ledctrl |= PHY_M_LED_BLINK_RT(BLINK_84MS) << 1;

                ctrl = gm_phy_read(hw, port, PHY_MARV_FE_LED_PAR);

                /* delete ACT LED control bits */
                ctrl &= ~PHY_M_FELP_LED1_MSK;
                /* change ACT LED control to blink mode */
                ctrl |= PHY_M_FELP_LED1_CTRL(LED_PAR_CTRL_ACT_BL);
                gm_phy_write(hw, port, PHY_MARV_FE_LED_PAR, ctrl);
                break;

        case CHIP_ID_YUKON_FE_P:
                /* Enable Link Partner Next Page */
                ctrl = gm_phy_read(hw, port, PHY_MARV_PHY_CTRL);
                ctrl |= PHY_M_PC_ENA_LIP_NP;

                /* disable Energy Detect and enable scrambler */
                ctrl &= ~(PHY_M_PC_ENA_ENE_DT | PHY_M_PC_DIS_SCRAMB);
                gm_phy_write(hw, port, PHY_MARV_PHY_CTRL, ctrl);

                /* set LED2 -> ACT, LED1 -> LINK, LED0 -> SPEED */
                ctrl = PHY_M_FELP_LED2_CTRL(LED_PAR_CTRL_ACT_BL) |
                        PHY_M_FELP_LED1_CTRL(LED_PAR_CTRL_LINK) |
                        PHY_M_FELP_LED0_CTRL(LED_PAR_CTRL_SPEED);

                gm_phy_write(hw, port, PHY_MARV_FE_LED_PAR, ctrl);
                break;

        case CHIP_ID_YUKON_XL:
                pg = gm_phy_read(hw, port, PHY_MARV_EXT_ADR);

                /* select page 3 to access LED control register */
                gm_phy_write(hw, port, PHY_MARV_EXT_ADR, 3);

                /* set LED Function Control register */
                gm_phy_write(hw, port, PHY_MARV_PHY_CTRL,
                             (PHY_M_LEDC_LOS_CTRL(1) |  /* LINK/ACT */
                              PHY_M_LEDC_INIT_CTRL(7) | /* 10 Mbps */
                              PHY_M_LEDC_STA1_CTRL(7) | /* 100 Mbps */
                              PHY_M_LEDC_STA0_CTRL(7)));        /* 1000 Mbps */

                /* set Polarity Control register */
                gm_phy_write(hw, port, PHY_MARV_PHY_STAT,
                             (PHY_M_POLC_LS1_P_MIX(4) |
                              PHY_M_POLC_IS0_P_MIX(4) |
                              PHY_M_POLC_LOS_CTRL(2) |
                              PHY_M_POLC_INIT_CTRL(2) |
                              PHY_M_POLC_STA1_CTRL(2) |
                              PHY_M_POLC_STA0_CTRL(2)));

                /* restore page register */
                gm_phy_write(hw, port, PHY_MARV_EXT_ADR, pg);
                break;

        case CHIP_ID_YUKON_EC_U:
        case CHIP_ID_YUKON_EX:
        case CHIP_ID_YUKON_SUPR:
                pg = gm_phy_read(hw, port, PHY_MARV_EXT_ADR);

                /* select page 3 to access LED control register */
                gm_phy_write(hw, port, PHY_MARV_EXT_ADR, 3);

                /* set LED Function Control register */
                gm_phy_write(hw, port, PHY_MARV_PHY_CTRL,
                             (PHY_M_LEDC_LOS_CTRL(1) |  /* LINK/ACT */
                              PHY_M_LEDC_INIT_CTRL(8) | /* 10 Mbps */
                              PHY_M_LEDC_STA1_CTRL(7) | /* 100 Mbps */
                              PHY_M_LEDC_STA0_CTRL(7)));/* 1000 Mbps */

                /* set Blink Rate in LED Timer Control Register */
                gm_phy_write(hw, port, PHY_MARV_INT_MASK,
                             ledctrl | PHY_M_LED_BLINK_RT(BLINK_84MS));
                /* restore page register */
                gm_phy_write(hw, port, PHY_MARV_EXT_ADR, pg);
                break;

        default:
                /* set Tx LED (LED_TX) to blink mode on Rx OR Tx activity */
                ledctrl |= PHY_M_LED_BLINK_RT(BLINK_84MS) | PHY_M_LEDC_TX_CTRL;

                /* turn off the Rx LED (LED_RX) */
                ledover |= PHY_M_LED_MO_RX(MO_LED_OFF);
        }

        if (hw->chip_id == CHIP_ID_YUKON_EC_U || hw->chip_id == CHIP_ID_YUKON_UL_2) {
                /* apply fixes in PHY AFE */
                gm_phy_write(hw, port, PHY_MARV_EXT_ADR, 255);

                /* increase differential signal amplitude in 10BASE-T */
                gm_phy_write(hw, port, 0x18, 0xaa99);
                gm_phy_write(hw, port, 0x17, 0x2011);

                if (hw->chip_id == CHIP_ID_YUKON_EC_U) {
                        /* fix for IEEE A/B Symmetry failure in 1000BASE-T */
                        gm_phy_write(hw, port, 0x18, 0xa204);
                        gm_phy_write(hw, port, 0x17, 0x2002);
                }

                /* set page register to 0 */
                gm_phy_write(hw, port, PHY_MARV_EXT_ADR, 0);
        } else if (hw->chip_id == CHIP_ID_YUKON_FE_P &&
                   hw->chip_rev == CHIP_REV_YU_FE2_A0) {
                /* apply workaround for integrated resistors calibration */
                gm_phy_write(hw, port, PHY_MARV_PAGE_ADDR, 17);
                gm_phy_write(hw, port, PHY_MARV_PAGE_DATA, 0x3f60);
        } else if (hw->chip_id == CHIP_ID_YUKON_OPT && hw->chip_rev == 0) {
                /* apply fixes in PHY AFE */
                gm_phy_write(hw, port, PHY_MARV_EXT_ADR, 0x00ff);

                /* apply RDAC termination workaround */
                gm_phy_write(hw, port, 24, 0x2800);
                gm_phy_write(hw, port, 23, 0x2001);

                /* set page register back to 0 */
                gm_phy_write(hw, port, PHY_MARV_EXT_ADR, 0);
        } else if (hw->chip_id != CHIP_ID_YUKON_EX &&
                   hw->chip_id < CHIP_ID_YUKON_SUPR) {
                /* no effect on Yukon-XL */
                gm_phy_write(hw, port, PHY_MARV_LED_CTRL, ledctrl);

                if (!(sky2->flags & SKY2_FLAG_AUTO_SPEED) ||
                    sky2->speed == SPEED_100) {
                        /* turn on 100 Mbps LED (LED_LINK100) */
                        ledover |= PHY_M_LED_MO_100(MO_LED_ON);
                }

                if (ledover)
                        gm_phy_write(hw, port, PHY_MARV_LED_OVER, ledover);

        }

        /* Enable phy interrupt on auto-negotiation complete (or link up) */
        if (sky2->flags & SKY2_FLAG_AUTO_SPEED)
                gm_phy_write(hw, port, PHY_MARV_INT_MASK, PHY_M_IS_AN_COMPL);
        else
                gm_phy_write(hw, port, PHY_MARV_INT_MASK, PHY_M_DEF_MSK);
}

static const u32 phy_power[] = { PCI_Y2_PHY1_POWD, PCI_Y2_PHY2_POWD };
static const u32 coma_mode[] = { PCI_Y2_PHY1_COMA, PCI_Y2_PHY2_COMA };

static void sky2_phy_power_up(struct sky2_hw *hw, unsigned port)
{
        u32 reg1;

        sky2_write8(hw, B2_TST_CTRL1, TST_CFG_WRITE_ON);
        reg1 = sky2_pci_read32(hw, PCI_DEV_REG1);
        reg1 &= ~phy_power[port];

        if (hw->chip_id == CHIP_ID_YUKON_XL && hw->chip_rev > CHIP_REV_YU_XL_A1)
                reg1 |= coma_mode[port];

        sky2_pci_write32(hw, PCI_DEV_REG1, reg1);
        sky2_write8(hw, B2_TST_CTRL1, TST_CFG_WRITE_OFF);
        sky2_pci_read32(hw, PCI_DEV_REG1);

        if (hw->chip_id == CHIP_ID_YUKON_FE)
                gm_phy_write(hw, port, PHY_MARV_CTRL, PHY_CT_ANE);
        else if (hw->flags & SKY2_HW_ADV_POWER_CTL)
                sky2_write8(hw, SK_REG(port, GPHY_CTRL), GPC_RST_CLR);
}

static void sky2_phy_power_down(struct sky2_hw *hw, unsigned port)
{
        u32 reg1;
        u16 ctrl;

        /* release GPHY Control reset */
        sky2_write8(hw, SK_REG(port, GPHY_CTRL), GPC_RST_CLR);

        /* release GMAC reset */
        sky2_write8(hw, SK_REG(port, GMAC_CTRL), GMC_RST_CLR);

        if (hw->flags & SKY2_HW_NEWER_PHY) {
                /* select page 2 to access MAC control register */
                gm_phy_write(hw, port, PHY_MARV_EXT_ADR, 2);

                ctrl = gm_phy_read(hw, port, PHY_MARV_PHY_CTRL);
                /* allow GMII Power Down */
                ctrl &= ~PHY_M_MAC_GMIF_PUP;
                gm_phy_write(hw, port, PHY_MARV_PHY_CTRL, ctrl);

                /* set page register back to 0 */
                gm_phy_write(hw, port, PHY_MARV_EXT_ADR, 0);
        }

        /* setup General Purpose Control Register */
        gma_write16(hw, port, GM_GP_CTRL,
                    GM_GPCR_FL_PASS | GM_GPCR_SPEED_100 |
                    GM_GPCR_AU_DUP_DIS | GM_GPCR_AU_FCT_DIS |
                    GM_GPCR_AU_SPD_DIS);

        if (hw->chip_id != CHIP_ID_YUKON_EC) {
                if (hw->chip_id == CHIP_ID_YUKON_EC_U) {
                        /* select page 2 to access MAC control register */
                        gm_phy_write(hw, port, PHY_MARV_EXT_ADR, 2);

                        ctrl = gm_phy_read(hw, port, PHY_MARV_PHY_CTRL);
                        /* enable Power Down */
                        ctrl |= PHY_M_PC_POW_D_ENA;
                        gm_phy_write(hw, port, PHY_MARV_PHY_CTRL, ctrl);

                        /* set page register back to 0 */
                        gm_phy_write(hw, port, PHY_MARV_EXT_ADR, 0);
                }

                /* set IEEE compatible Power Down Mode (dev. #4.99) */
                gm_phy_write(hw, port, PHY_MARV_CTRL, PHY_CT_PDOWN);
        }

        sky2_write8(hw, B2_TST_CTRL1, TST_CFG_WRITE_ON);
        reg1 = sky2_pci_read32(hw, PCI_DEV_REG1);
        reg1 |= phy_power[port];                /* set PHY to PowerDown/COMA Mode */
        sky2_pci_write32(hw, PCI_DEV_REG1, reg1);
        sky2_write8(hw, B2_TST_CTRL1, TST_CFG_WRITE_OFF);
}

/* Enable Rx/Tx */
static void sky2_enable_rx_tx(struct sky2_port *sky2)
{
        struct sky2_hw *hw = sky2->hw;
        unsigned port = sky2->port;
        u16 reg;

        reg = gma_read16(hw, port, GM_GP_CTRL);
        reg |= GM_GPCR_RX_ENA | GM_GPCR_TX_ENA;
        gma_write16(hw, port, GM_GP_CTRL, reg);
}

/* Force a renegotiation */
static void sky2_phy_reinit(struct sky2_port *sky2)
{
        spin_lock_bh(&sky2->phy_lock);
        sky2_phy_init(sky2->hw, sky2->port);
        sky2_enable_rx_tx(sky2);
        spin_unlock_bh(&sky2->phy_lock);
}

/* Put device in state to listen for Wake On Lan */
static void sky2_wol_init(struct sky2_port *sky2)
{
        struct sky2_hw *hw = sky2->hw;
        unsigned port = sky2->port;
        enum flow_control save_mode;
        u16 ctrl;

        /* Bring hardware out of reset */
        sky2_write16(hw, B0_CTST, CS_RST_CLR);
        sky2_write16(hw, SK_REG(port, GMAC_LINK_CTRL), GMLC_RST_CLR);

        sky2_write8(hw, SK_REG(port, GPHY_CTRL), GPC_RST_CLR);
        sky2_write8(hw, SK_REG(port, GMAC_CTRL), GMC_RST_CLR);

        /* Force to 10/100
         * sky2_reset will re-enable on resume
         */
        save_mode = sky2->flow_mode;
        ctrl = sky2->advertising;

        sky2->advertising &= ~(ADVERTISED_1000baseT_Half|ADVERTISED_1000baseT_Full);
        sky2->flow_mode = FC_NONE;

        spin_lock_bh(&sky2->phy_lock);
        sky2_phy_power_up(hw, port);
        sky2_phy_init(hw, port);
        spin_unlock_bh(&sky2->phy_lock);

        sky2->flow_mode = save_mode;
        sky2->advertising = ctrl;

        /* Set GMAC to no flow control and auto update for speed/duplex */
        gma_write16(hw, port, GM_GP_CTRL,
                    GM_GPCR_FC_TX_DIS|GM_GPCR_TX_ENA|GM_GPCR_RX_ENA|
                    GM_GPCR_DUP_FULL|GM_GPCR_FC_RX_DIS|GM_GPCR_AU_FCT_DIS);

        /* Set WOL address */
        memcpy_toio(hw->regs + WOL_REGS(port, WOL_MAC_ADDR),
                    sky2->netdev->dev_addr, ETH_ALEN);

        /* Turn on appropriate WOL control bits */
        sky2_write16(hw, WOL_REGS(port, WOL_CTRL_STAT), WOL_CTL_CLEAR_RESULT);
        ctrl = 0;
        if (sky2->wol & WAKE_PHY)
                ctrl |= WOL_CTL_ENA_PME_ON_LINK_CHG|WOL_CTL_ENA_LINK_CHG_UNIT;
        else
                ctrl |= WOL_CTL_DIS_PME_ON_LINK_CHG|WOL_CTL_DIS_LINK_CHG_UNIT;

        if (sky2->wol & WAKE_MAGIC)
                ctrl |= WOL_CTL_ENA_PME_ON_MAGIC_PKT|WOL_CTL_ENA_MAGIC_PKT_UNIT;
        else
                ctrl |= WOL_CTL_DIS_PME_ON_MAGIC_PKT|WOL_CTL_DIS_MAGIC_PKT_UNIT;

        ctrl |= WOL_CTL_DIS_PME_ON_PATTERN|WOL_CTL_DIS_PATTERN_UNIT;
        sky2_write16(hw, WOL_REGS(port, WOL_CTRL_STAT), ctrl);

        /* Disable PiG firmware */
        sky2_write16(hw, B0_CTST, Y2_HW_WOL_OFF);

        /* block receiver */
        sky2_write8(hw, SK_REG(port, RX_GMF_CTRL_T), GMF_RST_SET);
}

static void sky2_set_tx_stfwd(struct sky2_hw *hw, unsigned port)
{
        struct net_device *dev = hw->dev[port];

        if ( (hw->chip_id == CHIP_ID_YUKON_EX &&
              hw->chip_rev != CHIP_REV_YU_EX_A0) ||
             hw->chip_id >= CHIP_ID_YUKON_FE_P) {
                /* Yukon-Extreme B0 and further Extreme devices */
                sky2_write32(hw, SK_REG(port, TX_GMF_CTRL_T), TX_STFW_ENA);
        } else if (dev->mtu > ETH_DATA_LEN) {
                /* set Tx GMAC FIFO Almost Empty Threshold */
                sky2_write32(hw, SK_REG(port, TX_GMF_AE_THR),
                             (ECU_JUMBO_WM << 16) | ECU_AE_THR);

                sky2_write32(hw, SK_REG(port, TX_GMF_CTRL_T), TX_STFW_DIS);
        } else
                sky2_write32(hw, SK_REG(port, TX_GMF_CTRL_T), TX_STFW_ENA);
}

static void sky2_mac_init(struct sky2_hw *hw, unsigned port)
{
        struct sky2_port *sky2 = netdev_priv(hw->dev[port]);
        u16 reg;
        u32 rx_reg;
        int i;
        const u8 *addr = hw->dev[port]->dev_addr;

        sky2_write8(hw, SK_REG(port, GPHY_CTRL), GPC_RST_SET);
        sky2_write8(hw, SK_REG(port, GPHY_CTRL), GPC_RST_CLR);

        sky2_write8(hw, SK_REG(port, GMAC_CTRL), GMC_RST_CLR);

        if (hw->chip_id == CHIP_ID_YUKON_XL &&
            hw->chip_rev == CHIP_REV_YU_XL_A0 &&
            port == 1) {
                /* WA DEV_472 -- looks like crossed wires on port 2 */
                /* clear GMAC 1 Control reset */
                sky2_write8(hw, SK_REG(0, GMAC_CTRL), GMC_RST_CLR);
                do {
                        sky2_write8(hw, SK_REG(1, GMAC_CTRL), GMC_RST_SET);
                        sky2_write8(hw, SK_REG(1, GMAC_CTRL), GMC_RST_CLR);
                } while (gm_phy_read(hw, 1, PHY_MARV_ID0) != PHY_MARV_ID0_VAL ||
                         gm_phy_read(hw, 1, PHY_MARV_ID1) != PHY_MARV_ID1_Y2 ||
                         gm_phy_read(hw, 1, PHY_MARV_INT_MASK) != 0);
        }

        sky2_read16(hw, SK_REG(port, GMAC_IRQ_SRC));

        /* Enable Transmit FIFO Underrun */
        sky2_write8(hw, SK_REG(port, GMAC_IRQ_MSK), GMAC_DEF_MSK);

        spin_lock_bh(&sky2->phy_lock);
        sky2_phy_power_up(hw, port);
        sky2_phy_init(hw, port);
        spin_unlock_bh(&sky2->phy_lock);

        /* MIB clear */
        reg = gma_read16(hw, port, GM_PHY_ADDR);
        gma_write16(hw, port, GM_PHY_ADDR, reg | GM_PAR_MIB_CLR);

        for (i = GM_MIB_CNT_BASE; i <= GM_MIB_CNT_END; i += 4)
                gma_read16(hw, port, i);
        gma_write16(hw, port, GM_PHY_ADDR, reg);

        /* transmit control */
        gma_write16(hw, port, GM_TX_CTRL, TX_COL_THR(TX_COL_DEF));

        /* receive control reg: unicast + multicast + no FCS  */
        gma_write16(hw, port, GM_RX_CTRL,
                    GM_RXCR_UCF_ENA | GM_RXCR_CRC_DIS | GM_RXCR_MCF_ENA);

        /* transmit flow control */
        gma_write16(hw, port, GM_TX_FLOW_CTRL, 0xffff);

        /* transmit parameter */
        gma_write16(hw, port, GM_TX_PARAM,
                    TX_JAM_LEN_VAL(TX_JAM_LEN_DEF) |
                    TX_JAM_IPG_VAL(TX_JAM_IPG_DEF) |
                    TX_IPG_JAM_DATA(TX_IPG_JAM_DEF) |
                    TX_BACK_OFF_LIM(TX_BOF_LIM_DEF));

        /* serial mode register */
        reg = DATA_BLIND_VAL(DATA_BLIND_DEF) |
                GM_SMOD_VLAN_ENA | IPG_DATA_VAL(IPG_DATA_DEF);

        if (hw->dev[port]->mtu > ETH_DATA_LEN)
                reg |= GM_SMOD_JUMBO_ENA;

        if (hw->chip_id == CHIP_ID_YUKON_EC_U &&
            hw->chip_rev == CHIP_REV_YU_EC_U_B1)
                reg |= GM_NEW_FLOW_CTRL;

        gma_write16(hw, port, GM_SERIAL_MODE, reg);

        /* virtual address for data */
        gma_set_addr(hw, port, GM_SRC_ADDR_2L, addr);

        /* physical address: used for pause frames */
        gma_set_addr(hw, port, GM_SRC_ADDR_1L, addr);

        /* ignore counter overflows */
        gma_write16(hw, port, GM_TX_IRQ_MSK, 0);
        gma_write16(hw, port, GM_RX_IRQ_MSK, 0);
        gma_write16(hw, port, GM_TR_IRQ_MSK, 0);

        /* Configure Rx MAC FIFO */
        sky2_write8(hw, SK_REG(port, RX_GMF_CTRL_T), GMF_RST_CLR);
        rx_reg = GMF_OPER_ON | GMF_RX_F_FL_ON;
        if (hw->chip_id == CHIP_ID_YUKON_EX ||
            hw->chip_id == CHIP_ID_YUKON_FE_P)
                rx_reg |= GMF_RX_OVER_ON;

        sky2_write32(hw, SK_REG(port, RX_GMF_CTRL_T), rx_reg);

        if (hw->chip_id == CHIP_ID_YUKON_XL) {
                /* Hardware errata - clear flush mask */
                sky2_write16(hw, SK_REG(port, RX_GMF_FL_MSK), 0);
        } else {
                /* Flush Rx MAC FIFO on any flow control or error */
                sky2_write16(hw, SK_REG(port, RX_GMF_FL_MSK), GMR_FS_ANY_ERR);
        }

        /* Set threshold to 0xa (64 bytes) + 1 to workaround pause bug  */
        reg = RX_GMF_FL_THR_DEF + 1;
        /* Another magic mystery workaround from sk98lin */
        if (hw->chip_id == CHIP_ID_YUKON_FE_P &&
            hw->chip_rev == CHIP_REV_YU_FE2_A0)
                reg = 0x178;
        sky2_write16(hw, SK_REG(port, RX_GMF_FL_THR), reg);

        /* Configure Tx MAC FIFO */
        sky2_write8(hw, SK_REG(port, TX_GMF_CTRL_T), GMF_RST_CLR);
        sky2_write16(hw, SK_REG(port, TX_GMF_CTRL_T), GMF_OPER_ON);

        /* On chips without ram buffer, pause is controled by MAC level */
        if (!(hw->flags & SKY2_HW_RAM_BUFFER)) {
                /* Pause threshold is scaled by 8 in bytes */
                if (hw->chip_id == CHIP_ID_YUKON_FE_P &&
                    hw->chip_rev == CHIP_REV_YU_FE2_A0)
                        reg = 1568 / 8;
                else
                        reg = 1024 / 8;
                sky2_write16(hw, SK_REG(port, RX_GMF_UP_THR), reg);
                sky2_write16(hw, SK_REG(port, RX_GMF_LP_THR), 768 / 8);

                sky2_set_tx_stfwd(hw, port);
        }

        if (hw->chip_id == CHIP_ID_YUKON_FE_P &&
            hw->chip_rev == CHIP_REV_YU_FE2_A0) {
                /* disable dynamic watermark */
                reg = sky2_read16(hw, SK_REG(port, TX_GMF_EA));
                reg &= ~TX_DYN_WM_ENA;
                sky2_write16(hw, SK_REG(port, TX_GMF_EA), reg);
        }
}

/* Assign Ram Buffer allocation to queue */
static void sky2_ramset(struct sky2_hw *hw, u16 q, u32 start, u32 space)
{
        u32 end;

        /* convert from K bytes to qwords used for hw register */
        start *= 1024/8;
        space *= 1024/8;
        end = start + space - 1;

        sky2_write8(hw, RB_ADDR(q, RB_CTRL), RB_RST_CLR);
        sky2_write32(hw, RB_ADDR(q, RB_START), start);
        sky2_write32(hw, RB_ADDR(q, RB_END), end);
        sky2_write32(hw, RB_ADDR(q, RB_WP), start);
        sky2_write32(hw, RB_ADDR(q, RB_RP), start);

        if (q == Q_R1 || q == Q_R2) {
                u32 tp = space - space/4;

                /* On receive queue's set the thresholds
                 * give receiver priority when > 3/4 full
                 * send pause when down to 2K
                 */
                sky2_write32(hw, RB_ADDR(q, RB_RX_UTHP), tp);
                sky2_write32(hw, RB_ADDR(q, RB_RX_LTHP), space/2);

                tp = space - 2048/8;
                sky2_write32(hw, RB_ADDR(q, RB_RX_UTPP), tp);
                sky2_write32(hw, RB_ADDR(q, RB_RX_LTPP), space/4);
        } else {
                /* Enable store & forward on Tx queue's because
                 * Tx FIFO is only 1K on Yukon
                 */
                sky2_write8(hw, RB_ADDR(q, RB_CTRL), RB_ENA_STFWD);
        }

        sky2_write8(hw, RB_ADDR(q, RB_CTRL), RB_ENA_OP_MD);
        sky2_read8(hw, RB_ADDR(q, RB_CTRL));
}

/* Setup Bus Memory Interface */
static void sky2_qset(struct sky2_hw *hw, u16 q)
{

        sky2_write32(hw, Q_ADDR(q, Q_CSR), BMU_CLR_RESET);
        sky2_write32(hw, Q_ADDR(q, Q_CSR), BMU_OPER_INIT);
        sky2_write32(hw, Q_ADDR(q, Q_CSR), BMU_FIFO_OP_ON);
        sky2_write32(hw, Q_ADDR(q, Q_WM),  BMU_WM_DEFAULT);
}

/* Setup prefetch unit registers. This is the interface between
 * hardware and driver list elements
 */
static void sky2_prefetch_init(struct sky2_hw *hw, u32 qaddr,
                               dma_addr_t addr, u32 last)
{
        sky2_write32(hw, Y2_QADDR(qaddr, PREF_UNIT_CTRL), PREF_UNIT_RST_SET);
        sky2_write32(hw, Y2_QADDR(qaddr, PREF_UNIT_CTRL), PREF_UNIT_RST_CLR);
        sky2_write32(hw, Y2_QADDR(qaddr, PREF_UNIT_ADDR_HI), upper_32_bits(addr));
        sky2_write32(hw, Y2_QADDR(qaddr, PREF_UNIT_ADDR_LO), lower_32_bits(addr));
        sky2_write16(hw, Y2_QADDR(qaddr, PREF_UNIT_LAST_IDX), last);
        sky2_write32(hw, Y2_QADDR(qaddr, PREF_UNIT_CTRL), PREF_UNIT_OP_ON);

        sky2_read32(hw, Y2_QADDR(qaddr, PREF_UNIT_CTRL));
}

static inline struct sky2_tx_le *get_tx_le(struct sky2_port *sky2, u16 *slot)
{
        struct sky2_tx_le *le = sky2->tx_le + *slot;

        *slot = RING_NEXT(*slot, sky2->tx_ring_size);
        le->ctrl = 0;
        return le;
}

static void tx_init(struct sky2_port *sky2)
{
        struct sky2_tx_le *le;

        sky2->tx_prod = sky2->tx_cons = 0;
        sky2->tx_tcpsum = 0;
        sky2->tx_last_mss = 0;

        le = get_tx_le(sky2, &sky2->tx_prod);
        le->addr = 0;
        le->opcode = OP_ADDR64 | HW_OWNER;
        sky2->tx_last_upper = 0;
}

/* Update chip's next pointer */
static inline void sky2_put_idx(struct sky2_hw *hw, unsigned q, u16 idx)
{
        /* Make sure write' to descriptors are complete before we tell hardware */
        wmb();
        sky2_write16(hw, Y2_QADDR(q, PREF_UNIT_PUT_IDX), idx);

        /* Synchronize I/O on since next processor may write to tail */
        mmiowb();
}


static inline struct sky2_rx_le *sky2_next_rx(struct sky2_port *sky2)
{
        struct sky2_rx_le *le = sky2->rx_le + sky2->rx_put;
        sky2->rx_put = RING_NEXT(sky2->rx_put, RX_LE_SIZE);
        le->ctrl = 0;
        return le;
}

static unsigned sky2_get_rx_threshold(struct sky2_port *sky2)
{
        unsigned size;

        /* Space needed for frame data + headers rounded up */
        size = roundup(sky2->netdev->mtu + ETH_HLEN + VLAN_HLEN, 8);

        /* Stopping point for hardware truncation */
        return (size - 8) / sizeof(u32);
}

static unsigned sky2_get_rx_data_size(struct sky2_port *sky2)
{
        struct rx_ring_info *re;
        unsigned size;

        /* Space needed for frame data + headers rounded up */
        size = roundup(sky2->netdev->mtu + ETH_HLEN + VLAN_HLEN, 8);

        sky2->rx_nfrags = size >> PAGE_SHIFT;
        BUG_ON(sky2->rx_nfrags > ARRAY_SIZE(re->frag_addr));

        /* Compute residue after pages */
        size -= sky2->rx_nfrags << PAGE_SHIFT;

        /* Optimize to handle small packets and headers */
        if (size < copybreak)
                size = copybreak;
        if (size < ETH_HLEN)
                size = ETH_HLEN;

        return size;
}

/* Build description to hardware for one receive segment */
static void sky2_rx_add(struct sky2_port *sky2, u8 op,
                        dma_addr_t map, unsigned len)
{
        struct sky2_rx_le *le;

        if (sizeof(dma_addr_t) > sizeof(u32)) {
                le = sky2_next_rx(sky2);
                le->addr = cpu_to_le32(upper_32_bits(map));
                le->opcode = OP_ADDR64 | HW_OWNER;
        }

        le = sky2_next_rx(sky2);
        le->addr = cpu_to_le32(lower_32_bits(map));
        le->length = cpu_to_le16(len);
        le->opcode = op | HW_OWNER;
}

/* Build description to hardware for one possibly fragmented skb */
static void sky2_rx_submit(struct sky2_port *sky2,
                           const struct rx_ring_info *re)
{
        int i;

        sky2_rx_add(sky2, OP_PACKET, re->data_addr, sky2->rx_data_size);

        for (i = 0; i < skb_shinfo(re->skb)->nr_frags; i++)
                sky2_rx_add(sky2, OP_BUFFER, re->frag_addr[i], PAGE_SIZE);
}


static int sky2_rx_map_skb(struct pci_dev *pdev, struct rx_ring_info *re,
                            unsigned size)
{
        struct sk_buff *skb = re->skb;
        int i;

        re->data_addr = pci_map_single(pdev, skb->data, size, PCI_DMA_FROMDEVICE);
        if (pci_dma_mapping_error(pdev, re->data_addr))
                goto mapping_error;

        dma_unmap_len_set(re, data_size, size);

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

                re->frag_addr[i] = pci_map_page(pdev, frag->page,
                                                frag->page_offset,
                                                frag->size,
                                                PCI_DMA_FROMDEVICE);

                if (pci_dma_mapping_error(pdev, re->frag_addr[i]))
                        goto map_page_error;
        }
        return 0;

map_page_error:
        while (--i >= 0) {
                pci_unmap_page(pdev, re->frag_addr[i],
                               skb_shinfo(skb)->frags[i].size,
                               PCI_DMA_FROMDEVICE);
        }

        pci_unmap_single(pdev, re->data_addr, dma_unmap_len(re, data_size),
                         PCI_DMA_FROMDEVICE);

mapping_error:
        if (net_ratelimit())
                dev_warn(&pdev->dev, "%s: rx mapping error\n",
                         skb->dev->name);
        return -EIO;
}

static void sky2_rx_unmap_skb(struct pci_dev *pdev, struct rx_ring_info *re)
{
        struct sk_buff *skb = re->skb;
        int i;

        pci_unmap_single(pdev, re->data_addr, dma_unmap_len(re, data_size),
                         PCI_DMA_FROMDEVICE);

        for (i = 0; i < skb_shinfo(skb)->nr_frags; i++)
                pci_unmap_page(pdev, re->frag_addr[i],
                               skb_shinfo(skb)->frags[i].size,
                               PCI_DMA_FROMDEVICE);
}

/* Tell chip where to start receive checksum.
 * Actually has two checksums, but set both same to avoid possible byte
 * order problems.
 */
static void rx_set_checksum(struct sky2_port *sky2)
{
        struct sky2_rx_le *le = sky2_next_rx(sky2);

        le->addr = cpu_to_le32((ETH_HLEN << 16) | ETH_HLEN);
        le->ctrl = 0;
        le->opcode = OP_TCPSTART | HW_OWNER;

        sky2_write32(sky2->hw,
                     Q_ADDR(rxqaddr[sky2->port], Q_CSR),
                     (sky2->flags & SKY2_FLAG_RX_CHECKSUM)
                     ? BMU_ENA_RX_CHKSUM : BMU_DIS_RX_CHKSUM);
}

/* Enable/disable receive hash calculation (RSS) */
static void rx_set_rss(struct net_device *dev)
{
        struct sky2_port *sky2 = netdev_priv(dev);
        struct sky2_hw *hw = sky2->hw;
        int i, nkeys = 4;

        /* Supports IPv6 and other modes */
        if (hw->flags & SKY2_HW_NEW_LE) {
                nkeys = 10;
                sky2_write32(hw, SK_REG(sky2->port, RSS_CFG), HASH_ALL);
        }

        /* Program RSS initial values */
        if (dev->features & NETIF_F_RXHASH) {
                u32 key[nkeys];

                get_random_bytes(key, nkeys * sizeof(u32));
                for (i = 0; i < nkeys; i++)
                        sky2_write32(hw, SK_REG(sky2->port, RSS_KEY + i * 4),
                                     key[i]);

                /* Need to turn on (undocumented) flag to make hashing work  */
                sky2_write32(hw, SK_REG(sky2->port, RX_GMF_CTRL_T),
                             RX_STFW_ENA);

                sky2_write32(hw, Q_ADDR(rxqaddr[sky2->port], Q_CSR),
                             BMU_ENA_RX_RSS_HASH);
        } else
                sky2_write32(hw, Q_ADDR(rxqaddr[sky2->port], Q_CSR),
                             BMU_DIS_RX_RSS_HASH);
}

/*
 * The RX Stop command will not work for Yukon-2 if the BMU does not
 * reach the end of packet and since we can't make sure that we have
 * incoming data, we must reset the BMU while it is not doing a DMA
 * transfer. Since it is possible that the RX path is still active,
 * the RX RAM buffer will be stopped first, so any possible incoming
 * data will not trigger a DMA. After the RAM buffer is stopped, the
 * BMU is polled until any DMA in progress is ended and only then it
 * will be reset.
 */
static void sky2_rx_stop(struct sky2_port *sky2)
{
        struct sky2_hw *hw = sky2->hw;
        unsigned rxq = rxqaddr[sky2->port];
        int i;

        /* disable the RAM Buffer receive queue */
        sky2_write8(hw, RB_ADDR(rxq, RB_CTRL), RB_DIS_OP_MD);

        for (i = 0; i < 0xffff; i++)
                if (sky2_read8(hw, RB_ADDR(rxq, Q_RSL))
                    == sky2_read8(hw, RB_ADDR(rxq, Q_RL)))
                        goto stopped;

        netdev_warn(sky2->netdev, "receiver stop failed\n");
stopped:
        sky2_write32(hw, Q_ADDR(rxq, Q_CSR), BMU_RST_SET | BMU_FIFO_RST);

        /* reset the Rx prefetch unit */
        sky2_write32(hw, Y2_QADDR(rxq, PREF_UNIT_CTRL), PREF_UNIT_RST_SET);
        mmiowb();
}

/* Clean out receive buffer area, assumes receiver hardware stopped */
static void sky2_rx_clean(struct sky2_port *sky2)
{
        unsigned i;

        memset(sky2->rx_le, 0, RX_LE_BYTES);
        for (i = 0; i < sky2->rx_pending; i++) {
                struct rx_ring_info *re = sky2->rx_ring + i;

                if (re->skb) {
                        sky2_rx_unmap_skb(sky2->hw->pdev, re);
                        kfree_skb(re->skb);
                        re->skb = NULL;
                }
        }
}

/* Basic MII support */
static int sky2_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
{
        struct mii_ioctl_data *data = if_mii(ifr);
        struct sky2_port *sky2 = netdev_priv(dev);
        struct sky2_hw *hw = sky2->hw;
        int err = -EOPNOTSUPP;

        if (!netif_running(dev))
                return -ENODEV; /* Phy still in reset */

        switch (cmd) {
        case SIOCGMIIPHY:
                data->phy_id = PHY_ADDR_MARV;

                /* fallthru */
        case SIOCGMIIREG: {
                u16 val = 0;

                spin_lock_bh(&sky2->phy_lock);
                err = __gm_phy_read(hw, sky2->port, data->reg_num & 0x1f, &val);
                spin_unlock_bh(&sky2->phy_lock);

                data->val_out = val;
                break;
        }

        case SIOCSMIIREG:
                spin_lock_bh(&sky2->phy_lock);
                err = gm_phy_write(hw, sky2->port, data->reg_num & 0x1f,
                                   data->val_in);
                spin_unlock_bh(&sky2->phy_lock);
                break;
        }
        return err;
}

#define NETIF_F_ALL_VLAN (NETIF_F_HW_VLAN_TX|NETIF_F_HW_VLAN_RX)

static void sky2_vlan_mode(struct net_device *dev)
{
        struct sky2_port *sky2 = netdev_priv(dev);
        struct sky2_hw *hw = sky2->hw;
        u16 port = sky2->port;

        if (dev->features & NETIF_F_HW_VLAN_RX)
                sky2_write32(hw, SK_REG(port, RX_GMF_CTRL_T),
                             RX_VLAN_STRIP_ON);
        else
                sky2_write32(hw, SK_REG(port, RX_GMF_CTRL_T),
                             RX_VLAN_STRIP_OFF);

        dev->vlan_features = dev->features &~ NETIF_F_ALL_VLAN;
        if (dev->features & NETIF_F_HW_VLAN_TX)
                sky2_write32(hw, SK_REG(port, TX_GMF_CTRL_T),
                             TX_VLAN_TAG_ON);
        else {
                sky2_write32(hw, SK_REG(port, TX_GMF_CTRL_T),
                             TX_VLAN_TAG_OFF);

                /* Can't do transmit offload of vlan without hw vlan */
                dev->vlan_features &= ~(NETIF_F_TSO | NETIF_F_SG
                                        | NETIF_F_ALL_CSUM);
        }
}

/* Amount of required worst case padding in rx buffer */
static inline unsigned sky2_rx_pad(const struct sky2_hw *hw)
{
        return (hw->flags & SKY2_HW_RAM_BUFFER) ? 8 : 2;
}

/*
 * Allocate an skb for receiving. If the MTU is large enough
 * make the skb non-linear with a fragment list of pages.
 */
static struct sk_buff *sky2_rx_alloc(struct sky2_port *sky2)
{
        struct sk_buff *skb;
        int i;

        skb = netdev_alloc_skb(sky2->netdev,
                               sky2->rx_data_size + sky2_rx_pad(sky2->hw));
        if (!skb)
                goto nomem;

        if (sky2->hw->flags & SKY2_HW_RAM_BUFFER) {
                unsigned char *start;
                /*
                 * Workaround for a bug in FIFO that cause hang
                 * if the FIFO if the receive buffer is not 64 byte aligned.
                 * The buffer returned from netdev_alloc_skb is
                 * aligned except if slab debugging is enabled.
                 */
                start = PTR_ALIGN(skb->data, 8);
                skb_reserve(skb, start - skb->data);
        } else
                skb_reserve(skb, NET_IP_ALIGN);

        for (i = 0; i < sky2->rx_nfrags; i++) {
                struct page *page = alloc_page(GFP_ATOMIC);

                if (!page)
                        goto free_partial;
                skb_fill_page_desc(skb, i, page, 0, PAGE_SIZE);
        }

        return skb;
free_partial:
        kfree_skb(skb);
nomem:
        return NULL;
}

static inline void sky2_rx_update(struct sky2_port *sky2, unsigned rxq)
{
        sky2_put_idx(sky2->hw, rxq, sky2->rx_put);
}

static int sky2_alloc_rx_skbs(struct sky2_port *sky2)
{
        struct sky2_hw *hw = sky2->hw;
        unsigned i;

        sky2->rx_data_size = sky2_get_rx_data_size(sky2);

        /* Fill Rx ring */
        for (i = 0; i < sky2->rx_pending; i++) {
                struct rx_ring_info *re = sky2->rx_ring + i;

                re->skb = sky2_rx_alloc(sky2);
                if (!re->skb)
                        return -ENOMEM;

                if (sky2_rx_map_skb(hw->pdev, re, sky2->rx_data_size)) {
                        dev_kfree_skb(re->skb);
                        re->skb = NULL;
                        return -ENOMEM;
                }
        }
        return 0;
}

/*
 * Setup receiver buffer pool.
 * Normal case this ends up creating one list element for skb
 * in the receive ring. Worst case if using large MTU and each
 * allocation falls on a different 64 bit region, that results
 * in 6 list elements per ring entry.
 * One element is used for checksum enable/disable, and one
 * extra to avoid wrap.
 */
static void sky2_rx_start(struct sky2_port *sky2)
{
        struct sky2_hw *hw = sky2->hw;
        struct rx_ring_info *re;
        unsigned rxq = rxqaddr[sky2->port];
        unsigned i, thresh;

        sky2->rx_put = sky2->rx_next = 0;
        sky2_qset(hw, rxq);

        /* On PCI express lowering the watermark gives better performance */
        if (pci_find_capability(hw->pdev, PCI_CAP_ID_EXP))
                sky2_write32(hw, Q_ADDR(rxq, Q_WM), BMU_WM_PEX);

        /* These chips have no ram buffer?
         * MAC Rx RAM Read is controlled by hardware */
        if (hw->chip_id == CHIP_ID_YUKON_EC_U &&
            hw->chip_rev > CHIP_REV_YU_EC_U_A0)
                sky2_write32(hw, Q_ADDR(rxq, Q_TEST), F_M_RX_RAM_DIS);

        sky2_prefetch_init(hw, rxq, sky2->rx_le_map, RX_LE_SIZE - 1);

        if (!(hw->flags & SKY2_HW_NEW_LE))
                rx_set_checksum(sky2);

        if (!(hw->flags & SKY2_HW_RSS_BROKEN))
                rx_set_rss(sky2->netdev);

        /* submit Rx ring */
        for (i = 0; i < sky2->rx_pending; i++) {
                re = sky2->rx_ring + i;
                sky2_rx_submit(sky2, re);
        }

        /*
         * The receiver hangs if it receives frames larger than the
         * packet buffer. As a workaround, truncate oversize frames, but
         * the register is limited to 9 bits, so if you do frames > 2052
         * you better get the MTU right!
         */
        thresh = sky2_get_rx_threshold(sky2);
        if (thresh > 0x1ff)
                sky2_write32(hw, SK_REG(sky2->port, RX_GMF_CTRL_T), RX_TRUNC_OFF);
        else {
                sky2_write16(hw, SK_REG(sky2->port, RX_GMF_TR_THR), thresh);
                sky2_write32(hw, SK_REG(sky2->port, RX_GMF_CTRL_T), RX_TRUNC_ON);
        }

        /* Tell chip about available buffers */
        sky2_rx_update(sky2, rxq);

        if (hw->chip_id == CHIP_ID_YUKON_EX ||
            hw->chip_id == CHIP_ID_YUKON_SUPR) {
                /*
                 * Disable flushing of non ASF packets;
                 * must be done after initializing the BMUs;
                 * drivers without ASF support should do this too, otherwise
                 * it may happen that they cannot run on ASF devices;
                 * remember that the MAC FIFO isn't reset during initialization.
                 */
                sky2_write32(hw, SK_REG(sky2->port, RX_GMF_CTRL_T), RX_MACSEC_FLUSH_OFF);
        }

        if (hw->chip_id >= CHIP_ID_YUKON_SUPR) {
                /* Enable RX Home Address & Routing Header checksum fix */
                sky2_write16(hw, SK_REG(sky2->port, RX_GMF_FL_CTRL),
                             RX_IPV6_SA_MOB_ENA | RX_IPV6_DA_MOB_ENA);

                /* Enable TX Home Address & Routing Header checksum fix */
                sky2_write32(hw, Q_ADDR(txqaddr[sky2->port], Q_TEST),
                             TBMU_TEST_HOME_ADD_FIX_EN | TBMU_TEST_ROUTING_ADD_FIX_EN);
        }
}

static int sky2_alloc_buffers(struct sky2_port *sky2)
{
        struct sky2_hw *hw = sky2->hw;

        /* must be power of 2 */
        sky2->tx_le = pci_alloc_consistent(hw->pdev,
                                           sky2->tx_ring_size *
                                           sizeof(struct sky2_tx_le),
                                           &sky2->tx_le_map);
        if (!sky2->tx_le)
                goto nomem;

        sky2->tx_ring = kcalloc(sky2->tx_ring_size, sizeof(struct tx_ring_info),
                                GFP_KERNEL);
        if (!sky2->tx_ring)
                goto nomem;

        sky2->rx_le = pci_alloc_consistent(hw->pdev, RX_LE_BYTES,
                                           &sky2->rx_le_map);
        if (!sky2->rx_le)
                goto nomem;
        memset(sky2->rx_le, 0, RX_LE_BYTES);

        sky2->rx_ring = kcalloc(sky2->rx_pending, sizeof(struct rx_ring_info),
                                GFP_KERNEL);
        if (!sky2->rx_ring)
                goto nomem;

        return sky2_alloc_rx_skbs(sky2);
nomem:
        return -ENOMEM;
}

static void sky2_free_buffers(struct sky2_port *sky2)
{
        struct sky2_hw *hw = sky2->hw;

        sky2_rx_clean(sky2);

        if (sky2->rx_le) {
                pci_free_consistent(hw->pdev, RX_LE_BYTES,
                                    sky2->rx_le, sky2->rx_le_map);
                sky2->rx_le = NULL;
        }
        if (sky2->tx_le) {
                pci_free_consistent(hw->pdev,
                                    sky2->tx_ring_size * sizeof(struct sky2_tx_le),
                                    sky2->tx_le, sky2->tx_le_map);
                sky2->tx_le = NULL;
        }
        kfree(sky2->tx_ring);
        kfree(sky2->rx_ring);

        sky2->tx_ring = NULL;
        sky2->rx_ring = NULL;
}

static void sky2_hw_up(struct sky2_port *sky2)
{
        struct sky2_hw *hw = sky2->hw;
        unsigned port = sky2->port;
        u32 ramsize;
        int cap;
        struct net_device *otherdev = hw->dev[sky2->port^1];

        tx_init(sky2);

        /*
         * On dual port PCI-X card, there is an problem where status
         * can be received out of order due to split transactions
         */
        if (otherdev && netif_running(otherdev) &&
            (cap = pci_find_capability(hw->pdev, PCI_CAP_ID_PCIX))) {
                u16 cmd;

                cmd = sky2_pci_read16(hw, cap + PCI_X_CMD);
                cmd &= ~PCI_X_CMD_MAX_SPLIT;
                sky2_pci_write16(hw, cap + PCI_X_CMD, cmd);
        }

        sky2_mac_init(hw, port);

        /* Register is number of 4K blocks on internal RAM buffer. */
        ramsize = sky2_read8(hw, B2_E_0) * 4;
        if (ramsize > 0) {
                u32 rxspace;

                netdev_dbg(sky2->netdev, "ram buffer %dK\n", ramsize);
                if (ramsize < 16)
                        rxspace = ramsize / 2;
                else
                        rxspace = 8 + (2*(ramsize - 16))/3;

                sky2_ramset(hw, rxqaddr[port], 0, rxspace);
                sky2_ramset(hw, txqaddr[port], rxspace, ramsize - rxspace);

                /* Make sure SyncQ is disabled */
                sky2_write8(hw, RB_ADDR(port == 0 ? Q_XS1 : Q_XS2, RB_CTRL),
                            RB_RST_SET);
        }

        sky2_qset(hw, txqaddr[port]);

        /* This is copied from sk98lin 10.0.5.3; no one tells me about erratta's */
        if (hw->chip_id == CHIP_ID_YUKON_EX && hw->chip_rev == CHIP_REV_YU_EX_B0)
                sky2_write32(hw, Q_ADDR(txqaddr[port], Q_TEST), F_TX_CHK_AUTO_OFF);

        /* Set almost empty threshold */
        if (hw->chip_id == CHIP_ID_YUKON_EC_U &&
            hw->chip_rev == CHIP_REV_YU_EC_U_A0)
                sky2_write16(hw, Q_ADDR(txqaddr[port], Q_AL), ECU_TXFF_LEV);

        sky2_prefetch_init(hw, txqaddr[port], sky2->tx_le_map,
                           sky2->tx_ring_size - 1);

        sky2_vlan_mode(sky2->netdev);

        sky2_rx_start(sky2);
}

/* Bring up network interface. */
static int sky2_up(struct net_device *dev)
{
        struct sky2_port *sky2 = netdev_priv(dev);
        struct sky2_hw *hw = sky2->hw;
        unsigned port = sky2->port;
        u32 imask;
        int err;

        netif_carrier_off(dev);

        err = sky2_alloc_buffers(sky2);
        if (err)
                goto err_out;

        sky2_hw_up(sky2);

        /* Enable interrupts from phy/mac for port */
        imask = sky2_read32(hw, B0_IMSK);
        imask |= portirq_msk[port];
        sky2_write32(hw, B0_IMSK, imask);
        sky2_read32(hw, B0_IMSK);

        netif_info(sky2, ifup, dev, "enabling interface\n");

        return 0;

err_out:
        sky2_free_buffers(sky2);
        return err;
}

/* Modular subtraction in ring */
static inline int tx_inuse(const struct sky2_port *sky2)
{
        return (sky2->tx_prod - sky2->tx_cons) & (sky2->tx_ring_size - 1);
}

/* Number of list elements available for next tx */
static inline int tx_avail(const struct sky2_port *sky2)
{
        return sky2->tx_pending - tx_inuse(sky2);
}

/* Estimate of number of transmit list elements required */
static unsigned tx_le_req(const struct sk_buff *skb)
{
        unsigned count;

        count = (skb_shinfo(skb)->nr_frags + 1)
                * (sizeof(dma_addr_t) / sizeof(u32));

        if (skb_is_gso(skb))
                ++count;
        else if (sizeof(dma_addr_t) == sizeof(u32))
                ++count;        /* possible vlan */

        if (skb->ip_summed == CHECKSUM_PARTIAL)
                ++count;

        return count;
}

static void sky2_tx_unmap(struct pci_dev *pdev, struct tx_ring_info *re)
{
        if (re->flags & TX_MAP_SINGLE)
                pci_unmap_single(pdev, dma_unmap_addr(re, mapaddr),
                                 dma_unmap_len(re, maplen),
                                 PCI_DMA_TODEVICE);
        else if (re->flags & TX_MAP_PAGE)
                pci_unmap_page(pdev, dma_unmap_addr(re, mapaddr),
                               dma_unmap_len(re, maplen),
                               PCI_DMA_TODEVICE);
        re->flags = 0;
}

/*
 * Put one packet in ring for transmit.
 * A single packet can generate multiple list elements, and
 * the number of ring elements will probably be less than the number
 * of list elements used.
 */
static netdev_tx_t sky2_xmit_frame(struct sk_buff *skb,
                                   struct net_device *dev)
{
        struct sky2_port *sky2 = netdev_priv(dev);
        struct sky2_hw *hw = sky2->hw;
        struct sky2_tx_le *le = NULL;
        struct tx_ring_info *re;
        unsigned i, len;
        dma_addr_t mapping;
        u32 upper;
        u16 slot;
        u16 mss;
        u8 ctrl;

        if (unlikely(tx_avail(sky2) < tx_le_req(skb)))
                return NETDEV_TX_BUSY;

        len = skb_headlen(skb);
        mapping = pci_map_single(hw->pdev, skb->data, len, PCI_DMA_TODEVICE);

        if (pci_dma_mapping_error(hw->pdev, mapping))
                goto mapping_error;

        slot = sky2->tx_prod;
        netif_printk(sky2, tx_queued, KERN_DEBUG, dev,
                     "tx queued, slot %u, len %d\n", slot, skb->len);

        /* Send high bits if needed */
        upper = upper_32_bits(mapping);
        if (upper != sky2->tx_last_upper) {
                le = get_tx_le(sky2, &slot);
                le->addr = cpu_to_le32(upper);
                sky2->tx_last_upper = upper;
                le->opcode = OP_ADDR64 | HW_OWNER;
        }

        /* Check for TCP Segmentation Offload */
        mss = skb_shinfo(skb)->gso_size;
        if (mss != 0) {

                if (!(hw->flags & SKY2_HW_NEW_LE))
                        mss += ETH_HLEN + ip_hdrlen(skb) + tcp_hdrlen(skb);

                if (mss != sky2->tx_last_mss) {
                        le = get_tx_le(sky2, &slot);
                        le->addr = cpu_to_le32(mss);

                        if (hw->flags & SKY2_HW_NEW_LE)
                                le->opcode = OP_MSS | HW_OWNER;
                        else
                                le->opcode = OP_LRGLEN | HW_OWNER;
                        sky2->tx_last_mss = mss;
                }
        }

        ctrl = 0;

        /* Add VLAN tag, can piggyback on LRGLEN or ADDR64 */
        if (vlan_tx_tag_present(skb)) {
                if (!le) {
                        le = get_tx_le(sky2, &slot);
                        le->addr = 0;
                        le->opcode = OP_VLAN|HW_OWNER;
                } else
                        le->opcode |= OP_VLAN;
                le->length = cpu_to_be16(vlan_tx_tag_get(skb));
                ctrl |= INS_VLAN;
        }

        /* Handle TCP checksum offload */
        if (skb->ip_summed == CHECKSUM_PARTIAL) {
                /* On Yukon EX (some versions) encoding change. */
                if (hw->flags & SKY2_HW_AUTO_TX_SUM)
                        ctrl |= CALSUM; /* auto checksum */
                else {
                        const unsigned offset = skb_transport_offset(skb);
                        u32 tcpsum;

                        tcpsum = offset << 16;                  /* sum start */
                        tcpsum |= offset + skb->csum_offset;    /* sum write */

                        ctrl |= CALSUM | WR_SUM | INIT_SUM | LOCK_SUM;
                        if (ip_hdr(skb)->protocol == IPPROTO_UDP)
                                ctrl |= UDPTCP;

                        if (tcpsum != sky2->tx_tcpsum) {
                                sky2->tx_tcpsum = tcpsum;

                                le = get_tx_le(sky2, &slot);
                                le->addr = cpu_to_le32(tcpsum);
                                le->length = 0; /* initial checksum value */
                                le->ctrl = 1;   /* one packet */
                                le->opcode = OP_TCPLISW | HW_OWNER;
                        }
                }
        }

        re = sky2->tx_ring + slot;
        re->flags = TX_MAP_SINGLE;
        dma_unmap_addr_set(re, mapaddr, mapping);
        dma_unmap_len_set(re, maplen, len);

        le = get_tx_le(sky2, &slot);
        le->addr = cpu_to_le32(lower_32_bits(mapping));
        le->length = cpu_to_le16(len);
        le->ctrl = ctrl;
        le->opcode = mss ? (OP_LARGESEND | HW_OWNER) : (OP_PACKET | HW_OWNER);


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

                mapping = pci_map_page(hw->pdev, frag->page, frag->page_offset,
                                       frag->size, PCI_DMA_TODEVICE);

                if (pci_dma_mapping_error(hw->pdev, mapping))
                        goto mapping_unwind;

                upper = upper_32_bits(mapping);
                if (upper != sky2->tx_last_upper) {
                        le = get_tx_le(sky2, &slot);
                        le->addr = cpu_to_le32(upper);
                        sky2->tx_last_upper = upper;
                        le->opcode = OP_ADDR64 | HW_OWNER;
                }

                re = sky2->tx_ring + slot;
                re->flags = TX_MAP_PAGE;
                dma_unmap_addr_set(re, mapaddr, mapping);
                dma_unmap_len_set(re, maplen, frag->size);

                le = get_tx_le(sky2, &slot);
                le->addr = cpu_to_le32(lower_32_bits(mapping));
                le->length = cpu_to_le16(frag->size);
                le->ctrl = ctrl;
                le->opcode = OP_BUFFER | HW_OWNER;
        }

        re->skb = skb;
        le->ctrl |= EOP;

        sky2->tx_prod = slot;

        if (tx_avail(sky2) <= MAX_SKB_TX_LE)
                netif_stop_queue(dev);

        sky2_put_idx(hw, txqaddr[sky2->port], sky2->tx_prod);

        return NETDEV_TX_OK;

mapping_unwind:
        for (i = sky2->tx_prod; i != slot; i = RING_NEXT(i, sky2->tx_ring_size)) {
                re = sky2->tx_ring + i;

                sky2_tx_unmap(hw->pdev, re);
        }

mapping_error:
        if (net_ratelimit())
                dev_warn(&hw->pdev->dev, "%s: tx mapping error\n", dev->name);
        dev_kfree_skb(skb);
        return NETDEV_TX_OK;
}

/*
 * Free ring elements from starting at tx_cons until "done"
 *
 * NB:
 *  1. The hardware will tell us about partial completion of multi-part
 *     buffers so make sure not to free skb to early.
 *  2. This may run in parallel start_xmit because the it only
 *     looks at the tail of the queue of FIFO (tx_cons), not
 *     the head (tx_prod)
 */
static void sky2_tx_complete(struct sky2_port *sky2, u16 done)
{
        struct net_device *dev = sky2->netdev;
        unsigned idx;

        BUG_ON(done >= sky2->tx_ring_size);

        for (idx = sky2->tx_cons; idx != done;
             idx = RING_NEXT(idx, sky2->tx_ring_size)) {
                struct tx_ring_info *re = sky2->tx_ring + idx;
                struct sk_buff *skb = re->skb;

                sky2_tx_unmap(sky2->hw->pdev, re);

                if (skb) {
                        netif_printk(sky2, tx_done, KERN_DEBUG, dev,
                                     "tx done %u\n", idx);

                        u64_stats_update_begin(&sky2->tx_stats.syncp);
                        ++sky2->tx_stats.packets;
                        sky2->tx_stats.bytes += skb->len;
                        u64_stats_update_end(&sky2->tx_stats.syncp);

                        re->skb = NULL;
                        dev_kfree_skb_any(skb);

                        sky2->tx_next = RING_NEXT(idx, sky2->tx_ring_size);
                }
        }

        sky2->tx_cons = idx;
        smp_mb();
}

static void sky2_tx_reset(struct sky2_hw *hw, unsigned port)
{
        /* Disable Force Sync bit and Enable Alloc bit */
        sky2_write8(hw, SK_REG(port, TXA_CTRL),
                    TXA_DIS_FSYNC | TXA_DIS_ALLOC | TXA_STOP_RC);

        /* Stop Interval Timer and Limit Counter of Tx Arbiter */
        sky2_write32(hw, SK_REG(port, TXA_ITI_INI), 0L);
        sky2_write32(hw, SK_REG(port, TXA_LIM_INI), 0L);

        /* Reset the PCI FIFO of the async Tx queue */
        sky2_write32(hw, Q_ADDR(txqaddr[port], Q_CSR),
                     BMU_RST_SET | BMU_FIFO_RST);

        /* Reset the Tx prefetch units */
        sky2_write32(hw, Y2_QADDR(txqaddr[port], PREF_UNIT_CTRL),
                     PREF_UNIT_RST_SET);

        sky2_write32(hw, RB_ADDR(txqaddr[port], RB_CTRL), RB_RST_SET);
        sky2_write8(hw, SK_REG(port, TX_GMF_CTRL_T), GMF_RST_SET);
}

static void sky2_hw_down(struct sky2_port *sky2)
{
        struct sky2_hw *hw = sky2->hw;
        unsigned port = sky2->port;
        u16 ctrl;

        /* Force flow control off */
        sky2_write8(hw, SK_REG(port, GMAC_CTRL), GMC_PAUSE_OFF);

        /* Stop transmitter */
        sky2_write32(hw, Q_ADDR(txqaddr[port], Q_CSR), BMU_STOP);
        sky2_read32(hw, Q_ADDR(txqaddr[port], Q_CSR));

        sky2_write32(hw, RB_ADDR(txqaddr[port], RB_CTRL),
                     RB_RST_SET | RB_DIS_OP_MD);

        ctrl = gma_read16(hw, port, GM_GP_CTRL);
        ctrl &= ~(GM_GPCR_TX_ENA | GM_GPCR_RX_ENA);
        gma_write16(hw, port, GM_GP_CTRL, ctrl);

        sky2_write8(hw, SK_REG(port, GPHY_CTRL), GPC_RST_SET);

        /* Workaround shared GMAC reset */
        if (!(hw->chip_id == CHIP_ID_YUKON_XL && hw->chip_rev == 0 &&
              port == 0 && hw->dev[1] && netif_running(hw->dev[1])))
                sky2_write8(hw, SK_REG(port, GMAC_CTRL), GMC_RST_SET);

        sky2_write8(hw, SK_REG(port, RX_GMF_CTRL_T), GMF_RST_SET);

        /* Force any delayed status interrrupt and NAPI */
        sky2_write32(hw, STAT_LEV_TIMER_CNT, 0);
        sky2_write32(hw, STAT_TX_TIMER_CNT, 0);
        sky2_write32(hw, STAT_ISR_TIMER_CNT, 0);
        sky2_read8(hw, STAT_ISR_TIMER_CTRL);

        sky2_rx_stop(sky2);

        spin_lock_bh(&sky2->phy_lock);
        sky2_phy_power_down(hw, port);
        spin_unlock_bh(&sky2->phy_lock);

        sky2_tx_reset(hw, port);

        /* Free any pending frames stuck in HW queue */
        sky2_tx_complete(sky2, sky2->tx_prod);
}

/* Network shutdown */
static int sky2_down(struct net_device *dev)
{
        struct sky2_port *sky2 = netdev_priv(dev);
        struct sky2_hw *hw = sky2->hw;

        /* Never really got started! */
        if (!sky2->tx_le)

                return 0;

        netif_info(sky2, ifdown, dev, "disabling interface\n");

        /* Disable port IRQ */
        sky2_write32(hw, B0_IMSK,
                     sky2_read32(hw, B0_IMSK) & ~portirq_msk[sky2->port]);
        sky2_read32(hw, B0_IMSK);

        synchronize_irq(hw->pdev->irq);
        napi_synchronize(&hw->napi);

        sky2_hw_down(sky2);

        sky2_free_buffers(sky2);

        return 0;
}

static u16 sky2_phy_speed(const struct sky2_hw *hw, u16 aux)
{
        if (hw->flags & SKY2_HW_FIBRE_PHY)
                return SPEED_1000;

        if (!(hw->flags & SKY2_HW_GIGABIT)) {
                if (aux & PHY_M_PS_SPEED_100)
                        return SPEED_100;
                else
                        return SPEED_10;
        }

        switch (aux & PHY_M_PS_SPEED_MSK) {
        case PHY_M_PS_SPEED_1000:
                return SPEED_1000;
        case PHY_M_PS_SPEED_100:
                return SPEED_100;
        default:
                return SPEED_10;
        }
}

static void sky2_link_up(struct sky2_port *sky2)
{
        struct sky2_hw *hw = sky2->hw;
        unsigned port = sky2->port;
        static const char *fc_name[] = {
                [FC_NONE]       = "none",
                [FC_TX]         = "tx",
                [FC_RX]         = "rx",
                [FC_BOTH]       = "both",
        };

        sky2_enable_rx_tx(sky2);

        gm_phy_write(hw, port, PHY_MARV_INT_MASK, PHY_M_DEF_MSK);

        netif_carrier_on(sky2->netdev);

        mod_timer(&hw->watchdog_timer, jiffies + 1);

        /* Turn on link LED */
        sky2_write8(hw, SK_REG(port, LNK_LED_REG),
                    LINKLED_ON | LINKLED_BLINK_OFF | LINKLED_LINKSYNC_OFF);

        netif_info(sky2, link, sky2->netdev,
                   "Link is up at %d Mbps, %s duplex, flow control %s\n",
                   sky2->speed,
                   sky2->duplex == DUPLEX_FULL ? "full" : "half",
                   fc_name[sky2->flow_status]);
}

static void sky2_link_down(struct sky2_port *sky2)
{
        struct sky2_hw *hw = sky2->hw;
        unsigned port = sky2->port;
        u16 reg;

        gm_phy_write(hw, port, PHY_MARV_INT_MASK, 0);

        reg = gma_read16(hw, port, GM_GP_CTRL);
        reg &= ~(GM_GPCR_RX_ENA | GM_GPCR_TX_ENA);
        gma_write16(hw, port, GM_GP_CTRL, reg);

        netif_carrier_off(sky2->netdev);

        /* Turn off link LED */
        sky2_write8(hw, SK_REG(port, LNK_LED_REG), LINKLED_OFF);

        netif_info(sky2, link, sky2->netdev, "Link is down\n");

        sky2_phy_init(hw, port);
}

static enum flow_control sky2_flow(int rx, int tx)
{
        if (rx)
                return tx ? FC_BOTH : FC_RX;
        else
                return tx ? FC_TX : FC_NONE;
}

static int sky2_autoneg_done(struct sky2_port *sky2, u16 aux)
{
        struct sky2_hw *hw = sky2->hw;
        unsigned port = sky2->port;
        u16 advert, lpa;

        advert = gm_phy_read(hw, port, PHY_MARV_AUNE_ADV);
        lpa = gm_phy_read(hw, port, PHY_MARV_AUNE_LP);
        if (lpa & PHY_M_AN_RF) {
                netdev_err(sky2->netdev, "remote fault\n");
                return -1;
        }

        if (!(aux & PHY_M_PS_SPDUP_RES)) {
                netdev_err(sky2->netdev, "speed/duplex mismatch\n");
                return -1;
        }

        sky2->speed = sky2_phy_speed(hw, aux);
        sky2->duplex = (aux & PHY_M_PS_FULL_DUP) ? DUPLEX_FULL : DUPLEX_HALF;

        /* Since the pause result bits seem to in different positions on
         * different chips. look at registers.
         */
        if (hw->flags & SKY2_HW_FIBRE_PHY) {
                /* Shift for bits in fiber PHY */
                advert &= ~(ADVERTISE_PAUSE_CAP|ADVERTISE_PAUSE_ASYM);
                lpa &= ~(LPA_PAUSE_CAP|LPA_PAUSE_ASYM);

                if (advert & ADVERTISE_1000XPAUSE)
                        advert |= ADVERTISE_PAUSE_CAP;
                if (advert & ADVERTISE_1000XPSE_ASYM)
                        advert |= ADVERTISE_PAUSE_ASYM;
                if (lpa & LPA_1000XPAUSE)
                        lpa |= LPA_PAUSE_CAP;
                if (lpa & LPA_1000XPAUSE_ASYM)
                        lpa |= LPA_PAUSE_ASYM;
        }

        sky2->flow_status = FC_NONE;
        if (advert & ADVERTISE_PAUSE_CAP) {
                if (lpa & LPA_PAUSE_CAP)
                        sky2->flow_status = FC_BOTH;
                else if (advert & ADVERTISE_PAUSE_ASYM)
                        sky2->flow_status = FC_RX;
        } else if (advert & ADVERTISE_PAUSE_ASYM) {
                if ((lpa & LPA_PAUSE_CAP) && (lpa & LPA_PAUSE_ASYM))
                        sky2->flow_status = FC_TX;
        }

        if (sky2->duplex == DUPLEX_HALF && sky2->speed < SPEED_1000 &&
            !(hw->chip_id == CHIP_ID_YUKON_EC_U || hw->chip_id == CHIP_ID_YUKON_EX))
                sky2->flow_status = FC_NONE;

        if (sky2->flow_status & FC_TX)
                sky2_write8(hw, SK_REG(port, GMAC_CTRL), GMC_PAUSE_ON);
        else
                sky2_write8(hw, SK_REG(port, GMAC_CTRL), GMC_PAUSE_OFF);

        return 0;
}

/* Interrupt from PHY */
static void sky2_phy_intr(struct sky2_hw *hw, unsigned port)
{
        struct net_device *dev = hw->dev[port];
        struct sky2_port *sky2 = netdev_priv(dev);
        u16 istatus, phystat;

        if (!netif_running(dev))
                return;

        spin_lock(&sky2->phy_lock);
        istatus = gm_phy_read(hw, port, PHY_MARV_INT_STAT);
        phystat = gm_phy_read(hw, port, PHY_MARV_PHY_STAT);

        netif_info(sky2, intr, sky2->netdev, "phy interrupt status 0x%x 0x%x\n",
                   istatus, phystat);

        if (istatus & PHY_M_IS_AN_COMPL) {
                if (sky2_autoneg_done(sky2, phystat) == 0 &&
                    !netif_carrier_ok(dev))
                        sky2_link_up(sky2);
                goto out;
        }

        if (istatus & PHY_M_IS_LSP_CHANGE)
                sky2->speed = sky2_phy_speed(hw, phystat);

        if (istatus & PHY_M_IS_DUP_CHANGE)
                sky2->duplex =
                    (phystat & PHY_M_PS_FULL_DUP) ? DUPLEX_FULL : DUPLEX_HALF;

        if (istatus & PHY_M_IS_LST_CHANGE) {
                if (phystat & PHY_M_PS_LINK_UP)
                        sky2_link_up(sky2);
                else
                        sky2_link_down(sky2);
        }
out:
        spin_unlock(&sky2->phy_lock);
}

/* Special quick link interrupt (Yukon-2 Optima only) */
static void sky2_qlink_intr(struct sky2_hw *hw)
{
        struct sky2_port *sky2 = netdev_priv(hw->dev[0]);
        u32 imask;
        u16 phy;

        /* disable irq */
        imask = sky2_read32(hw, B0_IMSK);
        imask &= ~Y2_IS_PHY_QLNK;
        sky2_write32(hw, B0_IMSK, imask);

        /* reset PHY Link Detect */
        phy = sky2_pci_read16(hw, PSM_CONFIG_REG4);
        sky2_write8(hw, B2_TST_CTRL1, TST_CFG_WRITE_ON);
        sky2_pci_write16(hw, PSM_CONFIG_REG4, phy | 1);
        sky2_write8(hw, B2_TST_CTRL1, TST_CFG_WRITE_OFF);

        sky2_link_up(sky2);
}

/* Transmit timeout is only called if we are running, carrier is up
 * and tx queue is full (stopped).
 */
static void sky2_tx_timeout(struct net_device *dev)
{
        struct sky2_port *sky2 = netdev_priv(dev);
        struct sky2_hw *hw = sky2->hw;

        netif_err(sky2, timer, dev, "tx timeout\n");

        netdev_printk(KERN_DEBUG, dev, "transmit ring %u .. %u report=%u done=%u\n",
                      sky2->tx_cons, sky2->tx_prod,
                      sky2_read16(hw, sky2->port == 0 ? STAT_TXA1_RIDX : STAT_TXA2_RIDX),
                      sky2_read16(hw, Q_ADDR(txqaddr[sky2->port], Q_DONE)));

        /* can't restart safely under softirq */
        schedule_work(&hw->restart_work);
}

static int sky2_change_mtu(struct net_device *dev, int new_mtu)
{
        struct sky2_port *sky2 = netdev_priv(dev);
        struct sky2_hw *hw = sky2->hw;
        unsigned port = sky2->port;
        int err;
        u16 ctl, mode;
        u32 imask;

        /* MTU size outside the spec */
        if (new_mtu < ETH_ZLEN || new_mtu > ETH_JUMBO_MTU)
                return -EINVAL;

        /* MTU > 1500 on yukon FE and FE+ not allowed */
        if (new_mtu > ETH_DATA_LEN &&
            (hw->chip_id == CHIP_ID_YUKON_FE ||
             hw->chip_id == CHIP_ID_YUKON_FE_P))
                return -EINVAL;

        /* TSO, etc on Yukon Ultra and MTU > 1500 not supported */
        if (new_mtu > ETH_DATA_LEN && hw->chip_id == CHIP_ID_YUKON_EC_U)
                dev->features &= ~(NETIF_F_TSO|NETIF_F_SG|NETIF_F_ALL_CSUM);

        if (!netif_running(dev)) {
                dev->mtu = new_mtu;
                return 0;
        }

        imask = sky2_read32(hw, B0_IMSK);
        sky2_write32(hw, B0_IMSK, 0);

        dev->trans_start = jiffies;     /* prevent tx timeout */
        napi_disable(&hw->napi);
        netif_tx_disable(dev);

        synchronize_irq(hw->pdev->irq);

        if (!(hw->flags & SKY2_HW_RAM_BUFFER))
                sky2_set_tx_stfwd(hw, port);

        ctl = gma_read16(hw, port, GM_GP_CTRL);
        gma_write16(hw, port, GM_GP_CTRL, ctl & ~GM_GPCR_RX_ENA);
        sky2_rx_stop(sky2);
        sky2_rx_clean(sky2);

        dev->mtu = new_mtu;

        mode = DATA_BLIND_VAL(DATA_BLIND_DEF) |
                GM_SMOD_VLAN_ENA | IPG_DATA_VAL(IPG_DATA_DEF);

        if (dev->mtu > ETH_DATA_LEN)
                mode |= GM_SMOD_JUMBO_ENA;

        gma_write16(hw, port, GM_SERIAL_MODE, mode);

        sky2_write8(hw, RB_ADDR(rxqaddr[port], RB_CTRL), RB_ENA_OP_MD);

        err = sky2_alloc_rx_skbs(sky2);
        if (!err)
                sky2_rx_start(sky2);
        else
                sky2_rx_clean(sky2);
        sky2_write32(hw, B0_IMSK, imask);

        sky2_read32(hw, B0_Y2_SP_LISR);
        napi_enable(&hw->napi);

        if (err)
                dev_close(dev);
        else {
                gma_write16(hw, port, GM_GP_CTRL, ctl);

                netif_wake_queue(dev);
        }

        return err;
}

/* For small just reuse existing skb for next receive */
static struct sk_buff *receive_copy(struct sky2_port *sky2,
                                    const struct rx_ring_info *re,
                                    unsigned length)
{
        struct sk_buff *skb;

        skb = netdev_alloc_skb_ip_align(sky2->netdev, length);
        if (likely(skb)) {
                pci_dma_sync_single_for_cpu(sky2->hw->pdev, re->data_addr,
                                            length, PCI_DMA_FROMDEVICE);
                skb_copy_from_linear_data(re->skb, skb->data, length);
                skb->ip_summed = re->skb->ip_summed;
                skb->csum = re->skb->csum;
                pci_dma_sync_single_for_device(sky2->hw->pdev, re->data_addr,
                                               length, PCI_DMA_FROMDEVICE);
                re->skb->ip_summed = CHECKSUM_NONE;
                skb_put(skb, length);
        }
        return skb;
}

/* Adjust length of skb with fragments to match received data */
static void skb_put_frags(struct sk_buff *skb, unsigned int hdr_space,
                          unsigned int length)
{
        int i, num_frags;
        unsigned int size;

        /* put header into skb */
        size = min(length, hdr_space);
        skb->tail += size;
        skb->len += size;
        length -= size;

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

                if (length == 0) {
                        /* don't need this page */
                        __free_page(frag->page);
                        --skb_shinfo(skb)->nr_frags;
                } else {
                        size = min(length, (unsigned) PAGE_SIZE);

                        frag->size = size;
                        skb->data_len += size;
                        skb->truesize += size;
                        skb->len += size;
                        length -= size;
                }
        }
}

/* Normal packet - take skb from ring element and put in a new one  */
static struct sk_buff *receive_new(struct sky2_port *sky2,
                                   struct rx_ring_info *re,
                                   unsigned int length)
{
        struct sk_buff *skb;
        struct rx_ring_info nre;
        unsigned hdr_space = sky2->rx_data_size;

        nre.skb = sky2_rx_alloc(sky2);
        if (unlikely(!nre.skb))
                goto nobuf;

        if (sky2_rx_map_skb(sky2->hw->pdev, &nre, hdr_space))
                goto nomap;

        skb = re->skb;
        sky2_rx_unmap_skb(sky2->hw->pdev, re);
        prefetch(skb->data);
        *re = nre;

        if (skb_shinfo(skb)->nr_frags)
                skb_put_frags(skb, hdr_space, length);
        else
                skb_put(skb, length);
        return skb;

nomap:
        dev_kfree_skb(nre.skb);
nobuf:
        return NULL;
}

/*
 * Receive one packet.
 * For larger packets, get new buffer.
 */
static struct sk_buff *sky2_receive(struct net_device *dev,
                                    u16 length, u32 status)
{
        struct sky2_port *sky2 = netdev_priv(dev);
        struct rx_ring_info *re = sky2->rx_ring + sky2->rx_next;
        struct sk_buff *skb = NULL;
        u16 count = (status & GMR_FS_LEN) >> 16;

        if (status & GMR_FS_VLAN)
                count -= VLAN_HLEN;     /* Account for vlan tag */

        netif_printk(sky2, rx_status, KERN_DEBUG, dev,
                     "rx slot %u status 0x%x len %d\n",
                     sky2->rx_next, status, length);

        sky2->rx_next = (sky2->rx_next + 1) % sky2->rx_pending;
        prefetch(sky2->rx_ring + sky2->rx_next);

        /* This chip has hardware problems that generates bogus status.
         * So do only marginal checking and expect higher level protocols
         * to handle crap frames.
         */
        if (sky2->hw->chip_id == CHIP_ID_YUKON_FE_P &&
            sky2->hw->chip_rev == CHIP_REV_YU_FE2_A0 &&
            length != count)
                goto okay;

        if (status & GMR_FS_ANY_ERR)
                goto error;

        if (!(status & GMR_FS_RX_OK))
                goto resubmit;

        /* if length reported by DMA does not match PHY, packet was truncated */
        if (length != count)
                goto error;

okay:
        if (length < copybreak)
                skb = receive_copy(sky2, re, length);
        else
                skb = receive_new(sky2, re, length);

        dev->stats.rx_dropped += (skb == NULL);

resubmit:
        sky2_rx_submit(sky2, re);

        return skb;

error:
        ++dev->stats.rx_errors;

        if (net_ratelimit())
                netif_info(sky2, rx_err, dev,
                           "rx error, status 0x%x length %d\n", status, length);

        goto resubmit;
}

/* Transmit complete */
static inline void sky2_tx_done(struct net_device *dev, u16 last)
{
        struct sky2_port *sky2 = netdev_priv(dev);

        if (netif_running(dev)) {
                sky2_tx_complete(sky2, last);

                /* Wake unless it's detached, and called e.g. from sky2_down() */
                if (tx_avail(sky2) > MAX_SKB_TX_LE + 4)
                        netif_wake_queue(dev);
        }
}

static inline void sky2_skb_rx(const struct sky2_port *sky2,
                               u32 status, struct sk_buff *skb)
{
        if (status & GMR_FS_VLAN)
                __vlan_hwaccel_put_tag(skb, be16_to_cpu(sky2->rx_tag));

        if (skb->ip_summed == CHECKSUM_NONE)
                netif_receive_skb(skb);
        else
                napi_gro_receive(&sky2->hw->napi, skb);
}

static inline void sky2_rx_done(struct sky2_hw *hw, unsigned port,
                                unsigned packets, unsigned bytes)
{
        struct net_device *dev = hw->dev[port];
        struct sky2_port *sky2 = netdev_priv(dev);

        if (packets == 0)
                return;

        u64_stats_update_begin(&sky2->rx_stats.syncp);
        sky2->rx_stats.packets += packets;
        sky2->rx_stats.bytes += bytes;
        u64_stats_update_end(&sky2->rx_stats.syncp);

        dev->last_rx = jiffies;
        sky2_rx_update(netdev_priv(dev), rxqaddr[port]);
}

static void sky2_rx_checksum(struct sky2_port *sky2, u32 status)
{
        /* If this happens then driver assuming wrong format for chip type */
        BUG_ON(sky2->hw->flags & SKY2_HW_NEW_LE);

        /* Both checksum counters are programmed to start at
         * the same offset, so unless there is a problem they
         * should match. This failure is an early indication that
         * hardware receive checksumming won't work.
         */
        if (likely((u16)(status >> 16) == (u16)status)) {
                struct sk_buff *skb = sky2->rx_ring[sky2->rx_next].skb;
                skb->ip_summed = CHECKSUM_COMPLETE;
                skb->csum = le16_to_cpu(status);
        } else {
                dev_notice(&sky2->hw->pdev->dev,
                           "%s: receive checksum problem (status = %#x)\n",
                           sky2->netdev->name, status);

                /* Disable checksum offload */
                sky2->flags &= ~SKY2_FLAG_RX_CHECKSUM;
                sky2_write32(sky2->hw, Q_ADDR(rxqaddr[sky2->port], Q_CSR),
                             BMU_DIS_RX_CHKSUM);
        }
}

static void sky2_rx_hash(struct sky2_port *sky2, u32 status)
{
        struct sk_buff *skb;

        skb = sky2->rx_ring[sky2->rx_next].skb;
        skb->rxhash = le32_to_cpu(status);
}

/* Process status response ring */
static int sky2_status_intr(struct sky2_hw *hw, int to_do, u16 idx)
{
        int work_done = 0;
        unsigned int total_bytes[2] = { 0 };
        unsigned int total_packets[2] = { 0 };

        rmb();
        do {
                struct sky2_port *sky2;
                struct sky2_status_le *le  = hw->st_le + hw->st_idx;
                unsigned port;
                struct net_device *dev;
                struct sk_buff *skb;
                u32 status;
                u16 length;
                u8 opcode = le->opcode;

                if (!(opcode & HW_OWNER))
                        break;

                hw->st_idx = RING_NEXT(hw->st_idx, hw->st_size);

                port = le->css & CSS_LINK_BIT;
                dev = hw->dev[port];
                sky2 = netdev_priv(dev);
                length = le16_to_cpu(le->length);
                status = le32_to_cpu(le->status);

                le->opcode = 0;
                switch (opcode & ~HW_OWNER) {
                case OP_RXSTAT:
                        total_packets[port]++;
                        total_bytes[port] += length;

                        skb = sky2_receive(dev, length, status);
                        if (!skb)
                                break;

                        /* This chip reports checksum status differently */
                        if (hw->flags & SKY2_HW_NEW_LE) {
                                if ((sky2->flags & SKY2_FLAG_RX_CHECKSUM) &&
                                    (le->css & (CSS_ISIPV4 | CSS_ISIPV6)) &&
                                    (le->css & CSS_TCPUDPCSOK))
                                        skb->ip_summed = CHECKSUM_UNNECESSARY;
                                else
                                        skb->ip_summed = CHECKSUM_NONE;
                        }

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

                        sky2_skb_rx(sky2, status, skb);

                        /* Stop after net poll weight */
                        if (++work_done >= to_do)
                                goto exit_loop;
                        break;

                case OP_RXVLAN:
                        sky2->rx_tag = length;
                        break;

                case OP_RXCHKSVLAN:
                        sky2->rx_tag = length;
                        /* fall through */
                case OP_RXCHKS:
                        if (likely(sky2->flags & SKY2_FLAG_RX_CHECKSUM))
                                sky2_rx_checksum(sky2, status);
                        break;

                case OP_RSS_HASH:
                        sky2_rx_hash(sky2, status);
                        break;

                case OP_TXINDEXLE:
                        /* TX index reports status for both ports */
                        sky2_tx_done(hw->dev[0], status & 0xfff);
                        if (hw->dev[1])
                                sky2_tx_done(hw->dev[1],
                                     ((status >> 24) & 0xff)
                                             | (u16)(length & 0xf) << 8);
                        break;

                default:
                        if (net_ratelimit())
                                pr_warning("unknown status opcode 0x%x\n", opcode);
                }
        } while (hw->st_idx != idx);

        /* Fully processed status ring so clear irq */
        sky2_write32(hw, STAT_CTRL, SC_STAT_CLR_IRQ);

exit_loop:
        sky2_rx_done(hw, 0, total_packets[0], total_bytes[0]);
        sky2_rx_done(hw, 1, total_packets[1], total_bytes[1]);

        return work_done;
}

static void sky2_hw_error(struct sky2_hw *hw, unsigned port, u32 status)
{
        struct net_device *dev = hw->dev[port];

        if (net_ratelimit())
                netdev_info(dev, "hw error interrupt status 0x%x\n", status);

        if (status & Y2_IS_PAR_RD1) {
                if (net_ratelimit())
                        netdev_err(dev, "ram data read parity error\n");
                /* Clear IRQ */
                sky2_write16(hw, RAM_BUFFER(port, B3_RI_CTRL), RI_CLR_RD_PERR);
        }

        if (status & Y2_IS_PAR_WR1) {
                if (net_ratelimit())
                        netdev_err(dev, "ram data write parity error\n");

                sky2_write16(hw, RAM_BUFFER(port, B3_RI_CTRL), RI_CLR_WR_PERR);
        }

        if (status & Y2_IS_PAR_MAC1) {
                if (net_ratelimit())
                        netdev_err(dev, "MAC parity error\n");
                sky2_write8(hw, SK_REG(port, TX_GMF_CTRL_T), GMF_CLI_TX_PE);
        }

        if (status & Y2_IS_PAR_RX1) {
                if (net_ratelimit())
                        netdev_err(dev, "RX parity error\n");
                sky2_write32(hw, Q_ADDR(rxqaddr[port], Q_CSR), BMU_CLR_IRQ_PAR);
        }

        if (status & Y2_IS_TCP_TXA1) {
                if (net_ratelimit())
                        netdev_err(dev, "TCP segmentation error\n");
                sky2_write32(hw, Q_ADDR(txqaddr[port], Q_CSR), BMU_CLR_IRQ_TCP);
        }
}

static void sky2_hw_intr(struct sky2_hw *hw)
{
        struct pci_dev *pdev = hw->pdev;
        u32 status = sky2_read32(hw, B0_HWE_ISRC);
        u32 hwmsk = sky2_read32(hw, B0_HWE_IMSK);

        status &= hwmsk;

        if (status & Y2_IS_TIST_OV)
                sky2_write8(hw, GMAC_TI_ST_CTRL, GMT_ST_CLR_IRQ);

        if (status & (Y2_IS_MST_ERR | Y2_IS_IRQ_STAT)) {
                u16 pci_err;

                sky2_write8(hw, B2_TST_CTRL1, TST_CFG_WRITE_ON);
                pci_err = sky2_pci_read16(hw, PCI_STATUS);
                if (net_ratelimit())
                        dev_err(&pdev->dev, "PCI hardware error (0x%x)\n",
                                pci_err);

                sky2_pci_write16(hw, PCI_STATUS,
                                      pci_err | PCI_STATUS_ERROR_BITS);
                sky2_write8(hw, B2_TST_CTRL1, TST_CFG_WRITE_OFF);
        }

        if (status & Y2_IS_PCI_EXP) {
                /* PCI-Express uncorrectable Error occurred */
                u32 err;

                sky2_write8(hw, B2_TST_CTRL1, TST_CFG_WRITE_ON);
                err = sky2_read32(hw, Y2_CFG_AER + PCI_ERR_UNCOR_STATUS);
                sky2_write32(hw, Y2_CFG_AER + PCI_ERR_UNCOR_STATUS,
                             0xfffffffful);
                if (net_ratelimit())
                        dev_err(&pdev->dev, "PCI Express error (0x%x)\n", err);

                sky2_read32(hw, Y2_CFG_AER + PCI_ERR_UNCOR_STATUS);
                sky2_write8(hw, B2_TST_CTRL1, TST_CFG_WRITE_OFF);
        }

        if (status & Y2_HWE_L1_MASK)
                sky2_hw_error(hw, 0, status);
        status >>= 8;
        if (status & Y2_HWE_L1_MASK)
                sky2_hw_error(hw, 1, status);
}

static void sky2_mac_intr(struct sky2_hw *hw, unsigned port)
{
        struct net_device *dev = hw->dev[port];
        struct sky2_port *sky2 = netdev_priv(dev);
        u8 status = sky2_read8(hw, SK_REG(port, GMAC_IRQ_SRC));

        netif_info(sky2, intr, dev, "mac interrupt status 0x%x\n", status);

        if (status & GM_IS_RX_CO_OV)
                gma_read16(hw, port, GM_RX_IRQ_SRC);

        if (status & GM_IS_TX_CO_OV)
                gma_read16(hw, port, GM_TX_IRQ_SRC);

        if (status & GM_IS_RX_FF_OR) {
                ++dev->stats.rx_fifo_errors;
                sky2_write8(hw, SK_REG(port, RX_GMF_CTRL_T), GMF_CLI_RX_FO);
        }

        if (status & GM_IS_TX_FF_UR) {
                ++dev->stats.tx_fifo_errors;
                sky2_write8(hw, SK_REG(port, TX_GMF_CTRL_T), GMF_CLI_TX_FU);
        }
}

/* This should never happen it is a bug. */
static void sky2_le_error(struct sky2_hw *hw, unsigned port, u16 q)
{
        struct net_device *dev = hw->dev[port];
        u16 idx = sky2_read16(hw, Y2_QADDR(q, PREF_UNIT_GET_IDX));

        dev_err(&hw->pdev->dev, "%s: descriptor error q=%#x get=%u put=%u\n",
                dev->name, (unsigned) q, (unsigned) idx,
                (unsigned) sky2_read16(hw, Y2_QADDR(q, PREF_UNIT_PUT_IDX)));

        sky2_write32(hw, Q_ADDR(q, Q_CSR), BMU_CLR_IRQ_CHK);
}

static int sky2_rx_hung(struct net_device *dev)
{
        struct sky2_port *sky2 = netdev_priv(dev);
        struct sky2_hw *hw = sky2->hw;
        unsigned port = sky2->port;
        unsigned rxq = rxqaddr[port];
        u32 mac_rp = sky2_read32(hw, SK_REG(port, RX_GMF_RP));
        u8 mac_lev = sky2_read8(hw, SK_REG(port, RX_GMF_RLEV));
        u8 fifo_rp = sky2_read8(hw, Q_ADDR(rxq, Q_RP));
        u8 fifo_lev = sky2_read8(hw, Q_ADDR(rxq, Q_RL));

        /* If idle and MAC or PCI is stuck */
        if (sky2->check.last == dev->last_rx &&
            ((mac_rp == sky2->check.mac_rp &&
              mac_lev != 0 && mac_lev >= sky2->check.mac_lev) ||
             /* Check if the PCI RX hang */
             (fifo_rp == sky2->check.fifo_rp &&
              fifo_lev != 0 && fifo_lev >= sky2->check.fifo_lev))) {
                netdev_printk(KERN_DEBUG, dev,
                              "hung mac %d:%d fifo %d (%d:%d)\n",
                              mac_lev, mac_rp, fifo_lev,
                              fifo_rp, sky2_read8(hw, Q_ADDR(rxq, Q_WP)));
                return 1;
        } else {
                sky2->check.last = dev->last_rx;
                sky2->check.mac_rp = mac_rp;
                sky2->check.mac_lev = mac_lev;
                sky2->check.fifo_rp = fifo_rp;
                sky2->check.fifo_lev = fifo_lev;
                return 0;
        }
}

static void sky2_watchdog(unsigned long arg)
{
        struct sky2_hw *hw = (struct sky2_hw *) arg;

        /* Check for lost IRQ once a second */
        if (sky2_read32(hw, B0_ISRC)) {
                napi_schedule(&hw->napi);
        } else {
                int i, active = 0;

                for (i = 0; i < hw->ports; i++) {
                        struct net_device *dev = hw->dev[i];
                        if (!netif_running(dev))
                                continue;
                        ++active;

                        /* For chips with Rx FIFO, check if stuck */
                        if ((hw->flags & SKY2_HW_RAM_BUFFER) &&
                             sky2_rx_hung(dev)) {
                                netdev_info(dev, "receiver hang detected\n");
                                schedule_work(&hw->restart_work);
                                return;
                        }
                }

                if (active == 0)
                        return;
        }

        mod_timer(&hw->watchdog_timer, round_jiffies(jiffies + HZ));
}

/* Hardware/software error handling */
static void sky2_err_intr(struct sky2_hw *hw, u32 status)
{
        if (net_ratelimit())
                dev_warn(&hw->pdev->dev, "error interrupt status=%#x\n", status);

        if (status & Y2_IS_HW_ERR)
                sky2_hw_intr(hw);

        if (status & Y2_IS_IRQ_MAC1)
                sky2_mac_intr(hw, 0);

        if (status & Y2_IS_IRQ_MAC2)
                sky2_mac_intr(hw, 1);

        if (status & Y2_IS_CHK_RX1)
                sky2_le_error(hw, 0, Q_R1);

        if (status & Y2_IS_CHK_RX2)
                sky2_le_error(hw, 1, Q_R2);

        if (status & Y2_IS_CHK_TXA1)
                sky2_le_error(hw, 0, Q_XA1);

        if (status & Y2_IS_CHK_TXA2)
                sky2_le_error(hw, 1, Q_XA2);
}

static int sky2_poll(struct napi_struct *napi, int work_limit)
{
        struct sky2_hw *hw = container_of(napi, struct sky2_hw, napi);
        u32 status = sky2_read32(hw, B0_Y2_SP_EISR);
        int work_done = 0;
        u16 idx;

        if (unlikely(status & Y2_IS_ERROR))
                sky2_err_intr(hw, status);

        if (status & Y2_IS_IRQ_PHY1)
                sky2_phy_intr(hw, 0);

        if (status & Y2_IS_IRQ_PHY2)
                sky2_phy_intr(hw, 1);

        if (status & Y2_IS_PHY_QLNK)
                sky2_qlink_intr(hw);

        while ((idx = sky2_read16(hw, STAT_PUT_IDX)) != hw->st_idx) {
                work_done += sky2_status_intr(hw, work_limit - work_done, idx);

                if (work_done >= work_limit)
                        goto done;
        }

        napi_complete(napi);
        sky2_read32(hw, B0_Y2_SP_LISR);
done:

        return work_done;
}

static irqreturn_t sky2_intr(int irq, void *dev_id)
{
        struct sky2_hw *hw = dev_id;
        u32 status;

        /* Reading this mask interrupts as side effect */
        status = sky2_read32(hw, B0_Y2_SP_ISRC2);
        if (status == 0 || status == ~0)
                return IRQ_NONE;

        prefetch(&hw->st_le[hw->st_idx]);

        napi_schedule(&hw->napi);

        return IRQ_HANDLED;
}

#ifdef CONFIG_NET_POLL_CONTROLLER
static void sky2_netpoll(struct net_device *dev)
{
        struct sky2_port *sky2 = netdev_priv(dev);

        napi_schedule(&sky2->hw->napi);
}
#endif

/* Chip internal frequency for clock calculations */
static u32 sky2_mhz(const struct sky2_hw *hw)
{
        switch (hw->chip_id) {
        case CHIP_ID_YUKON_EC:
        case CHIP_ID_YUKON_EC_U:
        case CHIP_ID_YUKON_EX:
        case CHIP_ID_YUKON_SUPR:
        case CHIP_ID_YUKON_UL_2:
        case CHIP_ID_YUKON_OPT:
                return 125;

        case CHIP_ID_YUKON_FE:
                return 100;

        case CHIP_ID_YUKON_FE_P:
                return 50;

        case CHIP_ID_YUKON_XL:
                return 156;

        default:
                BUG();
        }
}

static inline u32 sky2_us2clk(const struct sky2_hw *hw, u32 us)
{
        return sky2_mhz(hw) * us;
}

static inline u32 sky2_clk2us(const struct sky2_hw *hw, u32 clk)
{
        return clk / sky2_mhz(hw);
}


static int __devinit sky2_init(struct sky2_hw *hw)
{
        u8 t8;

        /* Enable all clocks and check for bad PCI access */
        sky2_pci_write32(hw, PCI_DEV_REG3, 0);

        sky2_write8(hw, B0_CTST, CS_RST_CLR);

        hw->chip_id = sky2_read8(hw, B2_CHIP_ID);
        hw->chip_rev = (sky2_read8(hw, B2_MAC_CFG) & CFG_CHIP_R_MSK) >> 4;

        switch (hw->chip_id) {
        case CHIP_ID_YUKON_XL:
                hw->flags = SKY2_HW_GIGABIT | SKY2_HW_NEWER_PHY;
                if (hw->chip_rev < CHIP_REV_YU_XL_A2)
                        hw->flags |= SKY2_HW_RSS_BROKEN;
                break;

        case CHIP_ID_YUKON_EC_U:
                hw->flags = SKY2_HW_GIGABIT
                        | SKY2_HW_NEWER_PHY
                        | SKY2_HW_ADV_POWER_CTL;
                break;

        case CHIP_ID_YUKON_EX:
                hw->flags = SKY2_HW_GIGABIT
                        | SKY2_HW_NEWER_PHY
                        | SKY2_HW_NEW_LE
                        | SKY2_HW_ADV_POWER_CTL;

                /* New transmit checksum */
                if (hw->chip_rev != CHIP_REV_YU_EX_B0)
                        hw->flags |= SKY2_HW_AUTO_TX_SUM;
                break;