// SPDX-License-Identifier: GPL-2.0
/**
 * sni_ave.c - Socionext UniPhier AVE ethernet driver
 * Copyright 2014 Panasonic Corporation
 * Copyright 2015-2017 Socionext Inc.
 */

#include <linux/bitops.h>
#include <linux/clk.h>
#include <linux/etherdevice.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/iopoll.h>
#include <linux/mfd/syscon.h>
#include <linux/mii.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/of_net.h>
#include <linux/of_mdio.h>
#include <linux/of_platform.h>
#include <linux/phy.h>
#include <linux/regmap.h>
#include <linux/reset.h>
#include <linux/types.h>
#include <linux/u64_stats_sync.h>

/* General Register Group */
#define AVE_IDR                 0x000   /* ID */
#define AVE_VR                  0x004   /* Version */
#define AVE_GRR                 0x008   /* Global Reset */
#define AVE_CFGR                0x00c   /* Configuration */

/* Interrupt Register Group */
#define AVE_GIMR                0x100   /* Global Interrupt Mask */
#define AVE_GISR                0x104   /* Global Interrupt Status */

/* MAC Register Group */
#define AVE_TXCR                0x200   /* TX Setup */
#define AVE_RXCR                0x204   /* RX Setup */
#define AVE_RXMAC1R             0x208   /* MAC address (lower) */
#define AVE_RXMAC2R             0x20c   /* MAC address (upper) */
#define AVE_MDIOCTR             0x214   /* MDIO Control */
#define AVE_MDIOAR              0x218   /* MDIO Address */
#define AVE_MDIOWDR             0x21c   /* MDIO Data */
#define AVE_MDIOSR              0x220   /* MDIO Status */
#define AVE_MDIORDR             0x224   /* MDIO Rd Data */

/* Descriptor Control Register Group */
#define AVE_DESCC               0x300   /* Descriptor Control */
#define AVE_TXDC                0x304   /* TX Descriptor Configuration */
#define AVE_RXDC0               0x308   /* RX Descriptor Ring0 Configuration */
#define AVE_IIRQC               0x34c   /* Interval IRQ Control */

/* Packet Filter Register Group */
#define AVE_PKTF_BASE           0x800   /* PF Base Address */
#define AVE_PFMBYTE_BASE        0xd00   /* PF Mask Byte Base Address */
#define AVE_PFMBIT_BASE         0xe00   /* PF Mask Bit Base Address */
#define AVE_PFSEL_BASE          0xf00   /* PF Selector Base Address */
#define AVE_PFEN                0xffc   /* Packet Filter Enable */
#define AVE_PKTF(ent)           (AVE_PKTF_BASE + (ent) * 0x40)
#define AVE_PFMBYTE(ent)        (AVE_PFMBYTE_BASE + (ent) * 8)
#define AVE_PFMBIT(ent)         (AVE_PFMBIT_BASE + (ent) * 4)
#define AVE_PFSEL(ent)          (AVE_PFSEL_BASE + (ent) * 4)

/* 64bit descriptor memory */
#define AVE_DESC_SIZE_64        12      /* Descriptor Size */

#define AVE_TXDM_64             0x1000  /* Tx Descriptor Memory */
#define AVE_RXDM_64             0x1c00  /* Rx Descriptor Memory */

#define AVE_TXDM_SIZE_64        0x0ba0  /* Tx Descriptor Memory Size 3KB */
#define AVE_RXDM_SIZE_64        0x6000  /* Rx Descriptor Memory Size 24KB */

/* 32bit descriptor memory */
#define AVE_DESC_SIZE_32        8       /* Descriptor Size */

#define AVE_TXDM_32             0x1000  /* Tx Descriptor Memory */
#define AVE_RXDM_32             0x1800  /* Rx Descriptor Memory */

#define AVE_TXDM_SIZE_32        0x07c0  /* Tx Descriptor Memory Size 2KB */
#define AVE_RXDM_SIZE_32        0x4000  /* Rx Descriptor Memory Size 16KB */

/* RMII Bridge Register Group */
#define AVE_RSTCTRL             0x8028  /* Reset control */
#define AVE_RSTCTRL_RMIIRST     BIT(16)
#define AVE_LINKSEL             0x8034  /* Link speed setting */
#define AVE_LINKSEL_100M        BIT(0)

/* AVE_GRR */
#define AVE_GRR_RXFFR           BIT(5)  /* Reset RxFIFO */
#define AVE_GRR_PHYRST          BIT(4)  /* Reset external PHY */
#define AVE_GRR_GRST            BIT(0)  /* Reset all MAC */

/* AVE_CFGR */
#define AVE_CFGR_FLE            BIT(31) /* Filter Function */
#define AVE_CFGR_CHE            BIT(30) /* Checksum Function */
#define AVE_CFGR_MII            BIT(27) /* Func mode (1:MII/RMII, 0:RGMII) */
#define AVE_CFGR_IPFCEN         BIT(24) /* IP fragment sum Enable */

/* AVE_GISR (common with GIMR) */
#define AVE_GI_PHY              BIT(24) /* PHY interrupt */
#define AVE_GI_TX               BIT(16) /* Tx complete */
#define AVE_GI_RXERR            BIT(8)  /* Receive frame more than max size */
#define AVE_GI_RXOVF            BIT(7)  /* Overflow at the RxFIFO */
#define AVE_GI_RXDROP           BIT(6)  /* Drop packet */
#define AVE_GI_RXIINT           BIT(5)  /* Interval interrupt */

/* AVE_TXCR */
#define AVE_TXCR_FLOCTR         BIT(18) /* Flow control */
#define AVE_TXCR_TXSPD_1G       BIT(17)
#define AVE_TXCR_TXSPD_100      BIT(16)

/* AVE_RXCR */
#define AVE_RXCR_RXEN           BIT(30) /* Rx enable */
#define AVE_RXCR_FDUPEN         BIT(22) /* Interface mode */
#define AVE_RXCR_FLOCTR         BIT(21) /* Flow control */
#define AVE_RXCR_AFEN           BIT(19) /* MAC address filter */
#define AVE_RXCR_DRPEN          BIT(18) /* Drop pause frame */
#define AVE_RXCR_MPSIZ_MASK     GENMASK(10, 0)

/* AVE_MDIOCTR */
#define AVE_MDIOCTR_RREQ        BIT(3)  /* Read request */
#define AVE_MDIOCTR_WREQ        BIT(2)  /* Write request */

/* AVE_MDIOSR */
#define AVE_MDIOSR_STS          BIT(0)  /* access status */

/* AVE_DESCC */
#define AVE_DESCC_STATUS_MASK   GENMASK(31, 16)
#define AVE_DESCC_RD0           BIT(8)  /* Enable Rx descriptor Ring0 */
#define AVE_DESCC_RDSTP         BIT(4)  /* Pause Rx descriptor */
#define AVE_DESCC_TD            BIT(0)  /* Enable Tx descriptor */

/* AVE_TXDC */
#define AVE_TXDC_SIZE           GENMASK(27, 16) /* Size of Tx descriptor */
#define AVE_TXDC_ADDR           GENMASK(11, 0)  /* Start address */
#define AVE_TXDC_ADDR_START     0

/* AVE_RXDC0 */
#define AVE_RXDC0_SIZE          GENMASK(30, 16) /* Size of Rx descriptor */
#define AVE_RXDC0_ADDR          GENMASK(14, 0)  /* Start address */
#define AVE_RXDC0_ADDR_START    0

/* AVE_IIRQC */
#define AVE_IIRQC_EN0           BIT(27) /* Enable interval interrupt Ring0 */
#define AVE_IIRQC_BSCK          GENMASK(15, 0)  /* Interval count unit */

/* Command status for descriptor */
#define AVE_STS_OWN             BIT(31) /* Descriptor ownership */
#define AVE_STS_INTR            BIT(29) /* Request for interrupt */
#define AVE_STS_OK              BIT(27) /* Normal transmit */
/* TX */
#define AVE_STS_NOCSUM          BIT(28) /* No use HW checksum */
#define AVE_STS_1ST             BIT(26) /* Head of buffer chain */
#define AVE_STS_LAST            BIT(25) /* Tail of buffer chain */
#define AVE_STS_OWC             BIT(21) /* Out of window,Late Collision */
#define AVE_STS_EC              BIT(20) /* Excess collision occurred */
#define AVE_STS_PKTLEN_TX_MASK  GENMASK(15, 0)
/* RX */
#define AVE_STS_CSSV            BIT(21) /* Checksum check performed */
#define AVE_STS_CSER            BIT(20) /* Checksum error detected */
#define AVE_STS_PKTLEN_RX_MASK  GENMASK(10, 0)

/* Packet filter */
#define AVE_PFMBYTE_MASK0       (GENMASK(31, 8) | GENMASK(5, 0))
#define AVE_PFMBYTE_MASK1       GENMASK(25, 0)
#define AVE_PFMBIT_MASK         GENMASK(15, 0)

#define AVE_PF_SIZE             17      /* Number of all packet filter */
#define AVE_PF_MULTICAST_SIZE   7       /* Number of multicast filter */

#define AVE_PFNUM_FILTER        0       /* No.0 */
#define AVE_PFNUM_UNICAST       1       /* No.1 */
#define AVE_PFNUM_BROADCAST     2       /* No.2 */
#define AVE_PFNUM_MULTICAST     11      /* No.11-17 */

/* NETIF Message control */
#define AVE_DEFAULT_MSG_ENABLE  (NETIF_MSG_DRV    |     \
                                 NETIF_MSG_PROBE  |     \
                                 NETIF_MSG_LINK   |     \
                                 NETIF_MSG_TIMER  |     \
                                 NETIF_MSG_IFDOWN |     \
                                 NETIF_MSG_IFUP   |     \
                                 NETIF_MSG_RX_ERR |     \
                                 NETIF_MSG_TX_ERR)

/* Parameter for descriptor */
#define AVE_NR_TXDESC           64      /* Tx descriptor */
#define AVE_NR_RXDESC           256     /* Rx descriptor */

#define AVE_DESC_OFS_CMDSTS     0
#define AVE_DESC_OFS_ADDRL      4
#define AVE_DESC_OFS_ADDRU      8

/* Parameter for ethernet frame */
#define AVE_MAX_ETHFRAME        1518
#define AVE_FRAME_HEADROOM      2

/* Parameter for interrupt */
#define AVE_INTM_COUNT          20
#define AVE_FORCE_TXINTCNT      1

/* SG */
#define SG_ETPINMODE            0x540
#define SG_ETPINMODE_EXTPHY     BIT(1)  /* for LD11 */
#define SG_ETPINMODE_RMII(ins)  BIT(ins)

#define IS_DESC_64BIT(p)        ((p)->data->is_desc_64bit)

#define AVE_MAX_CLKS            4
#define AVE_MAX_RSTS            2

enum desc_id {
        AVE_DESCID_RX,
        AVE_DESCID_TX,
};

enum desc_state {
        AVE_DESC_RX_PERMIT,
        AVE_DESC_RX_SUSPEND,
        AVE_DESC_START,
        AVE_DESC_STOP,
};

struct ave_desc {
        struct sk_buff  *skbs;
        dma_addr_t      skbs_dma;
        size_t          skbs_dmalen;
};

struct ave_desc_info {
        u32     ndesc;          /* number of descriptor */
        u32     daddr;          /* start address of descriptor */
        u32     proc_idx;       /* index of processing packet */
        u32     done_idx;       /* index of processed packet */
        struct ave_desc *desc;  /* skb info related descriptor */
};

struct ave_stats {
        struct  u64_stats_sync  syncp;
        u64     packets;
        u64     bytes;
        u64     errors;
        u64     dropped;
        u64     collisions;
        u64     fifo_errors;
};

struct ave_private {
        void __iomem            *base;
        int                     irq;
        int                     phy_id;
        unsigned int            desc_size;
        u32                     msg_enable;
        int                     nclks;
        struct clk              *clk[AVE_MAX_CLKS];
        int                     nrsts;
        struct reset_control    *rst[AVE_MAX_RSTS];
        phy_interface_t         phy_mode;
        struct phy_device       *phydev;
        struct mii_bus          *mdio;
        struct regmap           *regmap;
        unsigned int            pinmode_mask;
        unsigned int            pinmode_val;
        u32                     wolopts;

        /* stats */
        struct ave_stats        stats_rx;
        struct ave_stats        stats_tx;

        /* NAPI support */
        struct net_device       *ndev;
        struct napi_struct      napi_rx;
        struct napi_struct      napi_tx;

        /* descriptor */
        struct ave_desc_info    rx;
        struct ave_desc_info    tx;

        /* flow control */
        int pause_auto;
        int pause_rx;
        int pause_tx;

        const struct ave_soc_data *data;
};

struct ave_soc_data {
        bool    is_desc_64bit;
        const char      *clock_names[AVE_MAX_CLKS];
        const char      *reset_names[AVE_MAX_RSTS];
        int     (*get_pinmode)(struct ave_private *priv,
                               phy_interface_t phy_mode, u32 arg);
};

static u32 ave_desc_read(struct net_device *ndev, enum desc_id id, int entry,
                         int offset)
{
        struct ave_private *priv = netdev_priv(ndev);
        u32 addr;

        addr = ((id == AVE_DESCID_TX) ? priv->tx.daddr : priv->rx.daddr)
                + entry * priv->desc_size + offset;

        return readl(priv->base + addr);
}

static u32 ave_desc_read_cmdsts(struct net_device *ndev, enum desc_id id,
                                int entry)
{
        return ave_desc_read(ndev, id, entry, AVE_DESC_OFS_CMDSTS);
}

static void ave_desc_write(struct net_device *ndev, enum desc_id id,
                           int entry, int offset, u32 val)
{
        struct ave_private *priv = netdev_priv(ndev);
        u32 addr;

        addr = ((id == AVE_DESCID_TX) ? priv->tx.daddr : priv->rx.daddr)
                + entry * priv->desc_size + offset;

        writel(val, priv->base + addr);
}

static void ave_desc_write_cmdsts(struct net_device *ndev, enum desc_id id,
                                  int entry, u32 val)
{
        ave_desc_write(ndev, id, entry, AVE_DESC_OFS_CMDSTS, val);
}

static void ave_desc_write_addr(struct net_device *ndev, enum desc_id id,
                                int entry, dma_addr_t paddr)
{
        struct ave_private *priv = netdev_priv(ndev);

        ave_desc_write(ndev, id, entry, AVE_DESC_OFS_ADDRL,
                       lower_32_bits(paddr));
        if (IS_DESC_64BIT(priv))
                ave_desc_write(ndev, id,
                               entry, AVE_DESC_OFS_ADDRU,
                               upper_32_bits(paddr));
}

static u32 ave_irq_disable_all(struct net_device *ndev)
{
        struct ave_private *priv = netdev_priv(ndev);
        u32 ret;

        ret = readl(priv->base + AVE_GIMR);
        writel(0, priv->base + AVE_GIMR);

        return ret;
}

static void ave_irq_restore(struct net_device *ndev, u32 val)
{
        struct ave_private *priv = netdev_priv(ndev);

        writel(val, priv->base + AVE_GIMR);
}

static void ave_irq_enable(struct net_device *ndev, u32 bitflag)
{
        struct ave_private *priv = netdev_priv(ndev);

        writel(readl(priv->base + AVE_GIMR) | bitflag, priv->base + AVE_GIMR);
        writel(bitflag, priv->base + AVE_GISR);
}

static void ave_hw_write_macaddr(struct net_device *ndev,
                                 const unsigned char *mac_addr,
                                 int reg1, int reg2)
{
        struct ave_private *priv = netdev_priv(ndev);

        writel(mac_addr[0] | mac_addr[1] << 8 |
               mac_addr[2] << 16 | mac_addr[3] << 24, priv->base + reg1);
        writel(mac_addr[4] | mac_addr[5] << 8, priv->base + reg2);
}

static void ave_hw_read_version(struct net_device *ndev, char *buf, int len)
{
        struct ave_private *priv = netdev_priv(ndev);
        u32 major, minor, vr;

        vr = readl(priv->base + AVE_VR);
        major = (vr & GENMASK(15, 8)) >> 8;
        minor = (vr & GENMASK(7, 0));
        snprintf(buf, len, "v%u.%u", major, minor);
}

static void ave_ethtool_get_drvinfo(struct net_device *ndev,
                                    struct ethtool_drvinfo *info)
{
        struct device *dev = ndev->dev.parent;

        strlcpy(info->driver, dev->driver->name, sizeof(info->driver));
        strlcpy(info->bus_info, dev_name(dev), sizeof(info->bus_info));
        ave_hw_read_version(ndev, info->fw_version, sizeof(info->fw_version));
}

static u32 ave_ethtool_get_msglevel(struct net_device *ndev)
{
        struct ave_private *priv = netdev_priv(ndev);

        return priv->msg_enable;
}

static void ave_ethtool_set_msglevel(struct net_device *ndev, u32 val)
{
        struct ave_private *priv = netdev_priv(ndev);

        priv->msg_enable = val;
}

static void ave_ethtool_get_wol(struct net_device *ndev,
                                struct ethtool_wolinfo *wol)
{
        wol->supported = 0;
        wol->wolopts   = 0;

        if (ndev->phydev)
                phy_ethtool_get_wol(ndev->phydev, wol);
}

static int ave_ethtool_set_wol(struct net_device *ndev,
                               struct ethtool_wolinfo *wol)
{
        int ret;

        if (!ndev->phydev ||
            (wol->wolopts & (WAKE_ARP | WAKE_MAGICSECURE)))
                return -EOPNOTSUPP;

        ret = phy_ethtool_set_wol(ndev->phydev, wol);
        if (!ret)
                device_set_wakeup_enable(&ndev->dev, !!wol->wolopts);

        return ret;
}

static void ave_ethtool_get_pauseparam(struct net_device *ndev,
                                       struct ethtool_pauseparam *pause)
{
        struct ave_private *priv = netdev_priv(ndev);

        pause->autoneg  = priv->pause_auto;
        pause->rx_pause = priv->pause_rx;
        pause->tx_pause = priv->pause_tx;
}

static int ave_ethtool_set_pauseparam(struct net_device *ndev,
                                      struct ethtool_pauseparam *pause)
{
        struct ave_private *priv = netdev_priv(ndev);
        struct phy_device *phydev = ndev->phydev;

        if (!phydev)
                return -EINVAL;

        priv->pause_auto = pause->autoneg;
        priv->pause_rx   = pause->rx_pause;
        priv->pause_tx   = pause->tx_pause;

        phy_set_asym_pause(phydev, pause->rx_pause, pause->tx_pause);

        return 0;
}

static const struct ethtool_ops ave_ethtool_ops = {
        .get_link_ksettings     = phy_ethtool_get_link_ksettings,
        .set_link_ksettings     = phy_ethtool_set_link_ksettings,
        .get_drvinfo            = ave_ethtool_get_drvinfo,
        .nway_reset             = phy_ethtool_nway_reset,
        .get_link               = ethtool_op_get_link,
        .get_msglevel           = ave_ethtool_get_msglevel,
        .set_msglevel           = ave_ethtool_set_msglevel,
        .get_wol                = ave_ethtool_get_wol,
        .set_wol                = ave_ethtool_set_wol,
        .get_pauseparam         = ave_ethtool_get_pauseparam,
        .set_pauseparam         = ave_ethtool_set_pauseparam,
};

static int ave_mdiobus_read(struct mii_bus *bus, int phyid, int regnum)
{
        struct net_device *ndev = bus->priv;
        struct ave_private *priv;
        u32 mdioctl, mdiosr;
        int ret;

        priv = netdev_priv(ndev);

        /* write address */
        writel((phyid << 8) | regnum, priv->base + AVE_MDIOAR);

        /* read request */
        mdioctl = readl(priv->base + AVE_MDIOCTR);
        writel((mdioctl | AVE_MDIOCTR_RREQ) & ~AVE_MDIOCTR_WREQ,
               priv->base + AVE_MDIOCTR);

        ret = readl_poll_timeout(priv->base + AVE_MDIOSR, mdiosr,
                                 !(mdiosr & AVE_MDIOSR_STS), 20, 2000);
        if (ret) {
                netdev_err(ndev, "failed to read (phy:%d reg:%x)\n",
                           phyid, regnum);
                return ret;
        }

        return readl(priv->base + AVE_MDIORDR) & GENMASK(15, 0);
}

static int ave_mdiobus_write(struct mii_bus *bus, int phyid, int regnum,
                             u16 val)
{
        struct net_device *ndev = bus->priv;
        struct ave_private *priv;
        u32 mdioctl, mdiosr;
        int ret;

        priv = netdev_priv(ndev);

        /* write address */
        writel((phyid << 8) | regnum, priv->base + AVE_MDIOAR);

        /* write data */
        writel(val, priv->base + AVE_MDIOWDR);

        /* write request */
        mdioctl = readl(priv->base + AVE_MDIOCTR);
        writel((mdioctl | AVE_MDIOCTR_WREQ) & ~AVE_MDIOCTR_RREQ,
               priv->base + AVE_MDIOCTR);

        ret = readl_poll_timeout(priv->base + AVE_MDIOSR, mdiosr,
                                 !(mdiosr & AVE_MDIOSR_STS), 20, 2000);
        if (ret)
                netdev_err(ndev, "failed to write (phy:%d reg:%x)\n",
                           phyid, regnum);

        return ret;
}

static int ave_dma_map(struct net_device *ndev, struct ave_desc *desc,
                       void *ptr, size_t len, enum dma_data_direction dir,
                       dma_addr_t *paddr)
{
        dma_addr_t map_addr;

        map_addr = dma_map_single(ndev->dev.parent, ptr, len, dir);
        if (unlikely(dma_mapping_error(ndev->dev.parent, map_addr)))
                return -ENOMEM;

        desc->skbs_dma = map_addr;
        desc->skbs_dmalen = len;
        *paddr = map_addr;

        return 0;
}

static void ave_dma_unmap(struct net_device *ndev, struct ave_desc *desc,
                          enum dma_data_direction dir)
{
        if (!desc->skbs_dma)
                return;

        dma_unmap_single(ndev->dev.parent,
                         desc->skbs_dma, desc->skbs_dmalen, dir);
        desc->skbs_dma = 0;
}

/* Prepare Rx descriptor and memory */
static int ave_rxdesc_prepare(struct net_device *ndev, int entry)
{
        struct ave_private *priv = netdev_priv(ndev);
        struct sk_buff *skb;
        dma_addr_t paddr;
        int ret;

        skb = priv->rx.desc[entry].skbs;
        if (!skb) {
                skb = netdev_alloc_skb(ndev, AVE_MAX_ETHFRAME);
                if (!skb) {
                        netdev_err(ndev, "can't allocate skb for Rx\n");
                        return -ENOMEM;
                }
                skb->data += AVE_FRAME_HEADROOM;
                skb->tail += AVE_FRAME_HEADROOM;
        }

        /* set disable to cmdsts */
        ave_desc_write_cmdsts(ndev, AVE_DESCID_RX, entry,
                              AVE_STS_INTR | AVE_STS_OWN);

        /* map Rx buffer
         * Rx buffer set to the Rx descriptor has two restrictions:
         * - Rx buffer address is 4 byte aligned.
         * - Rx buffer begins with 2 byte headroom, and data will be put from
         *   (buffer + 2).
         * To satisfy this, specify the address to put back the buffer
         * pointer advanced by AVE_FRAME_HEADROOM, and expand the map size
         * by AVE_FRAME_HEADROOM.
         */
        ret = ave_dma_map(ndev, &priv->rx.desc[entry],
                          skb->data - AVE_FRAME_HEADROOM,
                          AVE_MAX_ETHFRAME + AVE_FRAME_HEADROOM,
                          DMA_FROM_DEVICE, &paddr);
        if (ret) {
                netdev_err(ndev, "can't map skb for Rx\n");
                dev_kfree_skb_any(skb);
                return ret;
        }
        priv->rx.desc[entry].skbs = skb;

        /* set buffer pointer */
        ave_desc_write_addr(ndev, AVE_DESCID_RX, entry, paddr);

        /* set enable to cmdsts */
        ave_desc_write_cmdsts(ndev, AVE_DESCID_RX, entry,
                              AVE_STS_INTR | AVE_MAX_ETHFRAME);

        return ret;
}

/* Switch state of descriptor */
static int ave_desc_switch(struct net_device *ndev, enum desc_state state)
{
        struct ave_private *priv = netdev_priv(ndev);
        int ret = 0;
        u32 val;

        switch (state) {
        case AVE_DESC_START:
                writel(AVE_DESCC_TD | AVE_DESCC_RD0, priv->base + AVE_DESCC);
                break;

        case AVE_DESC_STOP:
                writel(0, priv->base + AVE_DESCC);
                if (readl_poll_timeout(priv->base + AVE_DESCC, val, !val,
                                       150, 15000)) {
                        netdev_err(ndev, "can't stop descriptor\n");
                        ret = -EBUSY;
                }
                break;

        case AVE_DESC_RX_SUSPEND:
                val = readl(priv->base + AVE_DESCC);
                val |= AVE_DESCC_RDSTP;
                val &= ~AVE_DESCC_STATUS_MASK;
                writel(val, priv->base + AVE_DESCC);
                if (readl_poll_timeout(priv->base + AVE_DESCC, val,
                                       val & (AVE_DESCC_RDSTP << 16),
                                       150, 150000)) {
                        netdev_err(ndev, "can't suspend descriptor\n");
                        ret = -EBUSY;
                }
                break;

        case AVE_DESC_RX_PERMIT:
                val = readl(priv->base + AVE_DESCC);
                val &= ~AVE_DESCC_RDSTP;
                val &= ~AVE_DESCC_STATUS_MASK;
                writel(val, priv->base + AVE_DESCC);
                break;

        default:
                ret = -EINVAL;
                break;
        }

        return ret;
}

static int ave_tx_complete(struct net_device *ndev)
{
        struct ave_private *priv = netdev_priv(ndev);
        u32 proc_idx, done_idx, ndesc, cmdsts;
        unsigned int nr_freebuf = 0;
        unsigned int tx_packets = 0;
        unsigned int tx_bytes = 0;

        proc_idx = priv->tx.proc_idx;
        done_idx = priv->tx.done_idx;
        ndesc    = priv->tx.ndesc;

        /* free pre-stored skb from done_idx to proc_idx */
        while (proc_idx != done_idx) {
                cmdsts = ave_desc_read_cmdsts(ndev, AVE_DESCID_TX, done_idx);

                /* do nothing if owner is HW (==1 for Tx) */
                if (cmdsts & AVE_STS_OWN)
                        break;

                /* check Tx status and updates statistics */
                if (cmdsts & AVE_STS_OK) {
                        tx_bytes += cmdsts & AVE_STS_PKTLEN_TX_MASK;
                        /* success */
                        if (cmdsts & AVE_STS_LAST)
                                tx_packets++;
                } else {
                        /* error */
                        if (cmdsts & AVE_STS_LAST) {
                                priv->stats_tx.errors++;
                                if (cmdsts & (AVE_STS_OWC | AVE_STS_EC))
                                        priv->stats_tx.collisions++;
                        }
                }

                /* release skb */
                if (priv->tx.desc[done_idx].skbs) {
                        ave_dma_unmap(ndev, &priv->tx.desc[done_idx],
                                      DMA_TO_DEVICE);
                        dev_consume_skb_any(priv->tx.desc[done_idx].skbs);
                        priv->tx.desc[done_idx].skbs = NULL;
                        nr_freebuf++;
                }
                done_idx = (done_idx + 1) % ndesc;
        }

        priv->tx.done_idx = done_idx;

        /* update stats */
        u64_stats_update_begin(&priv->stats_tx.syncp);
        priv->stats_tx.packets += tx_packets;
        priv->stats_tx.bytes   += tx_bytes;
        u64_stats_update_end(&priv->stats_tx.syncp);

        /* wake queue for freeing buffer */
        if (unlikely(netif_queue_stopped(ndev)) && nr_freebuf)
                netif_wake_queue(ndev);

        return nr_freebuf;
}

static int ave_rx_receive(struct net_device *ndev, int num)
{
        struct ave_private *priv = netdev_priv(ndev);
        unsigned int rx_packets = 0;
        unsigned int rx_bytes = 0;
        u32 proc_idx, done_idx;
        struct sk_buff *skb;
        unsigned int pktlen;
        int restpkt, npkts;
        u32 ndesc, cmdsts;

        proc_idx = priv->rx.proc_idx;
        done_idx = priv->rx.done_idx;
        ndesc    = priv->rx.ndesc;
        restpkt  = ((proc_idx + ndesc - 1) - done_idx) % ndesc;

        for (npkts = 0; npkts < num; npkts++) {
                /* we can't receive more packet, so fill desc quickly */
                if (--restpkt < 0)
                        break;

                cmdsts = ave_desc_read_cmdsts(ndev, AVE_DESCID_RX, proc_idx);

                /* do nothing if owner is HW (==0 for Rx) */
                if (!(cmdsts & AVE_STS_OWN))
                        break;

                if (!(cmdsts & AVE_STS_OK)) {
                        priv->stats_rx.errors++;
                        proc_idx = (proc_idx + 1) % ndesc;
                        continue;
                }

                pktlen = cmdsts & AVE_STS_PKTLEN_RX_MASK;

                /* get skbuff for rx */
                skb = priv->rx.desc[proc_idx].skbs;
                priv->rx.desc[proc_idx].skbs = NULL;

                ave_dma_unmap(ndev, &priv->rx.desc[proc_idx], DMA_FROM_DEVICE);

                skb->dev = ndev;
                skb_put(skb, pktlen);
                skb->protocol = eth_type_trans(skb, ndev);

                if ((cmdsts & AVE_STS_CSSV) && (!(cmdsts & AVE_STS_CSER)))
                        skb->ip_summed = CHECKSUM_UNNECESSARY;

                rx_packets++;
                rx_bytes += pktlen;

                netif_receive_skb(skb);

                proc_idx = (proc_idx + 1) % ndesc;
        }

        priv->rx.proc_idx = proc_idx;

        /* update stats */
        u64_stats_update_begin(&priv->stats_rx.syncp);
        priv->stats_rx.packets += rx_packets;
        priv->stats_rx.bytes   += rx_bytes;
        u64_stats_update_end(&priv->stats_rx.syncp);

        /* refill the Rx buffers */
        while (proc_idx != done_idx) {
                if (ave_rxdesc_prepare(ndev, done_idx))
                        break;
                done_idx = (done_idx + 1) % ndesc;
        }

        priv->rx.done_idx = done_idx;

        return npkts;
}

static int ave_napi_poll_rx(struct napi_struct *napi, int budget)
{
        struct ave_private *priv;
        struct net_device *ndev;
        int num;

        priv = container_of(napi, struct ave_private, napi_rx);
        ndev = priv->ndev;

        num = ave_rx_receive(ndev, budget);
        if (num < budget) {
                napi_complete_done(napi, num);

                /* enable Rx interrupt when NAPI finishes */
                ave_irq_enable(ndev, AVE_GI_RXIINT);
        }

        return num;
}

static int ave_napi_poll_tx(struct napi_struct *napi, int budget)
{
        struct ave_private *priv;
        struct net_device *ndev;
        int num;

        priv = container_of(napi, struct ave_private, napi_tx);
        ndev = priv->ndev;

        num = ave_tx_complete(ndev);
        napi_complete(napi);

        /* enable Tx interrupt when NAPI finishes */
        ave_irq_enable(ndev, AVE_GI_TX);

        return num;
}

static void ave_global_reset(struct net_device *ndev)
{
        struct ave_private *priv = netdev_priv(ndev);
        u32 val;

        /* set config register */
        val = AVE_CFGR_FLE | AVE_CFGR_IPFCEN | AVE_CFGR_CHE;
        if (!phy_interface_mode_is_rgmii(priv->phy_mode))
                val |= AVE_CFGR_MII;
        writel(val, priv->base + AVE_CFGR);

        /* reset RMII register */
        val = readl(priv->base + AVE_RSTCTRL);
        val &= ~AVE_RSTCTRL_RMIIRST;
        writel(val, priv->base + AVE_RSTCTRL);

        /* assert reset */
        writel(AVE_GRR_GRST | AVE_GRR_PHYRST, priv->base + AVE_GRR);
        msleep(20);

        /* 1st, negate PHY reset only */
        writel(AVE_GRR_GRST, priv->base + AVE_GRR);
        msleep(40);

        /* negate reset */
        writel(0, priv->base + AVE_GRR);
        msleep(40);

        /* negate RMII register */
        val = readl(priv->base + AVE_RSTCTRL);
        val |= AVE_RSTCTRL_RMIIRST;
        writel(val, priv->base + AVE_RSTCTRL);

        ave_irq_disable_all(ndev);
}

static void ave_rxfifo_reset(struct net_device *ndev)
{
        struct ave_private *priv = netdev_priv(ndev);
        u32 rxcr_org;

        /* save and disable MAC receive op */
        rxcr_org = readl(priv->base + AVE_RXCR);
        writel(rxcr_org & (~AVE_RXCR_RXEN), priv->base + AVE_RXCR);

        /* suspend Rx descriptor */
        ave_desc_switch(ndev, AVE_DESC_RX_SUSPEND);

        /* receive all packets before descriptor starts */
        ave_rx_receive(ndev, priv->rx.ndesc);

        /* assert reset */
        writel(AVE_GRR_RXFFR, priv->base + AVE_GRR);
        udelay(50);

        /* negate reset */
        writel(0, priv->base + AVE_GRR);
        udelay(20);

        /* negate interrupt status */
        writel(AVE_GI_RXOVF, priv->base + AVE_GISR);

        /* permit descriptor */
        ave_desc_switch(ndev, AVE_DESC_RX_PERMIT);

        /* restore MAC reccieve op */
        writel(rxcr_org, priv->base + AVE_RXCR);
}

static irqreturn_t ave_irq_handler(int irq, void *netdev)
{
        struct net_device *ndev = (struct net_device *)netdev;
        struct ave_private *priv = netdev_priv(ndev);
        u32 gimr_val, gisr_val;

        gimr_val = ave_irq_disable_all(ndev);

        /* get interrupt status */
        gisr_val = readl(priv->base + AVE_GISR);

        /* PHY */
        if (gisr_val & AVE_GI_PHY)
                writel(AVE_GI_PHY, priv->base + AVE_GISR);

        /* check exceeding packet */
        if (gisr_val & AVE_GI_RXERR) {
                writel(AVE_GI_RXERR, priv->base + AVE_GISR);
                netdev_err(ndev, "receive a packet exceeding frame buffer\n");
        }

        gisr_val &= gimr_val;
        if (!gisr_val)
                goto exit_isr;

        /* RxFIFO overflow */
        if (gisr_val & AVE_GI_RXOVF) {
                priv->stats_rx.fifo_errors++;
                ave_rxfifo_reset(ndev);
                goto exit_isr;
        }

        /* Rx drop */
        if (gisr_val & AVE_GI_RXDROP) {
                priv->stats_rx.dropped++;
                writel(AVE_GI_RXDROP, priv->base + AVE_GISR);
        }

        /* Rx interval */
        if (gisr_val & AVE_GI_RXIINT) {
                napi_schedule(&priv->napi_rx);
                /* still force to disable Rx interrupt until NAPI finishes */
                gimr_val &= ~AVE_GI_RXIINT;
        }

        /* Tx completed */
        if (gisr_val & AVE_GI_TX) {
                napi_schedule(&priv->napi_tx);
                /* still force to disable Tx interrupt until NAPI finishes */
                gimr_val &= ~AVE_GI_TX;
        }

exit_isr:
        ave_irq_restore(ndev, gimr_val);

        return IRQ_HANDLED;
}

static int ave_pfsel_start(struct net_device *ndev, unsigned int entry)
{
        struct ave_private *priv = netdev_priv(ndev);
        u32 val;

        if (WARN_ON(entry > AVE_PF_SIZE))
                return -EINVAL;

        val = readl(priv->base + AVE_PFEN);
        writel(val | BIT(entry), priv->base + AVE_PFEN);

        return 0;
}

static int ave_pfsel_stop(struct net_device *ndev, unsigned int entry)
{
        struct ave_private *priv = netdev_priv(ndev);
        u32 val;

        if (WARN_ON(entry > AVE_PF_SIZE))
                return -EINVAL;

        val = readl(priv->base + AVE_PFEN);
        writel(val & ~BIT(entry), priv->base + AVE_PFEN);

        return 0;

}

static int ave_pfsel_set_macaddr(struct net_device *ndev,
                                 unsigned int entry,
                                 const unsigned char *mac_addr,
                                 unsigned int set_size)
{
        struct ave_private *priv = netdev_priv(ndev);

        if (WARN_ON(entry > AVE_PF_SIZE))
                return -EINVAL;
        if (WARN_ON(set_size > 6))
                return -EINVAL;

        ave_pfsel_stop(ndev, entry);

        /* set MAC address for the filter */
        ave_hw_write_macaddr(ndev, mac_addr,
                             AVE_PKTF(entry), AVE_PKTF(entry) + 4);

        /* set byte mask */
        writel(GENMASK(31, set_size) & AVE_PFMBYTE_MASK0,
               priv->base + AVE_PFMBYTE(entry));
        writel(AVE_PFMBYTE_MASK1, priv->base + AVE_PFMBYTE(entry) + 4);

        /* set bit mask filter */
        writel(AVE_PFMBIT_MASK, priv->base + AVE_PFMBIT(entry));

        /* set selector to ring 0 */
        writel(0, priv->base + AVE_PFSEL(entry));

        /* restart filter */
        ave_pfsel_start(ndev, entry);

        return 0;
}

static void ave_pfsel_set_promisc(struct net_device *ndev,
                                  unsigned int entry, u32 rxring)
{
        struct ave_private *priv = netdev_priv(ndev);

        if (WARN_ON(entry > AVE_PF_SIZE))
                return;

        ave_pfsel_stop(ndev, entry);

        /* set byte mask */
        writel(AVE_PFMBYTE_MASK0, priv->base + AVE_PFMBYTE(entry));
        writel(AVE_PFMBYTE_MASK1, priv->base + AVE_PFMBYTE(entry) + 4);

        /* set bit mask filter */
        writel(AVE_PFMBIT_MASK, priv->base + AVE_PFMBIT(entry));

        /* set selector to rxring */
        writel(rxring, priv->base + AVE_PFSEL(entry));

        ave_pfsel_start(ndev, entry);
}

static void ave_pfsel_init(struct net_device *ndev)
{
        unsigned char bcast_mac[ETH_ALEN];
        int i;

        eth_broadcast_addr(bcast_mac);

        for (i = 0; i < AVE_PF_SIZE; i++)
                ave_pfsel_stop(ndev, i);

        /* promiscious entry, select ring 0 */
        ave_pfsel_set_promisc(ndev, AVE_PFNUM_FILTER, 0);

        /* unicast entry */
        ave_pfsel_set_macaddr(ndev, AVE_PFNUM_UNICAST, ndev->dev_addr, 6);

        /* broadcast entry */
        ave_pfsel_set_macaddr(ndev, AVE_PFNUM_BROADCAST, bcast_mac, 6);
}

static void ave_phy_adjust_link(struct net_device *ndev)
{
        struct ave_private *priv = netdev_priv(ndev);
        struct phy_device *phydev = ndev->phydev;
        u32 val, txcr, rxcr, rxcr_org;
        u16 rmt_adv = 0, lcl_adv = 0;
        u8 cap;

        /* set RGMII speed */
        val = readl(priv->base + AVE_TXCR);
        val &= ~(AVE_TXCR_TXSPD_100 | AVE_TXCR_TXSPD_1G);

        if (phy_interface_is_rgmii(phydev) && phydev->speed == SPEED_1000)
                val |= AVE_TXCR_TXSPD_1G;
        else if (phydev->speed == SPEED_100)
                val |= AVE_TXCR_TXSPD_100;

        writel(val, priv->base + AVE_TXCR);

        /* set RMII speed (100M/10M only) */
        if (!phy_interface_is_rgmii(phydev)) {
                val = readl(priv->base + AVE_LINKSEL);
                if (phydev->speed == SPEED_10)
                        val &= ~AVE_LINKSEL_100M;
                else
                        val |= AVE_LINKSEL_100M;
                writel(val, priv->base + AVE_LINKSEL);
        }

        /* check current RXCR/TXCR */
        rxcr = readl(priv->base + AVE_RXCR);
        txcr = readl(priv->base + AVE_TXCR);
        rxcr_org = rxcr;

        if (phydev->duplex) {
                rxcr |= AVE_RXCR_FDUPEN;

                if (phydev->pause)
                        rmt_adv |= LPA_PAUSE_CAP;
                if (phydev->asym_pause)
                        rmt_adv |= LPA_PAUSE_ASYM;

                lcl_adv = linkmode_adv_to_lcl_adv_t(phydev->advertising);
                cap = mii_resolve_flowctrl_fdx(lcl_adv, rmt_adv);
                if (cap & FLOW_CTRL_TX)
                        txcr |= AVE_TXCR_FLOCTR;
                else
                        txcr &= ~AVE_TXCR_FLOCTR;
                if (cap & FLOW_CTRL_RX)
                        rxcr |= AVE_RXCR_FLOCTR;
                else
                        rxcr &= ~AVE_RXCR_FLOCTR;
        } else {
                rxcr &= ~AVE_RXCR_FDUPEN;
                rxcr &= ~AVE_RXCR_FLOCTR;
                txcr &= ~AVE_TXCR_FLOCTR;
        }

        if (rxcr_org != rxcr) {
                /* disable Rx mac */
                writel(rxcr & ~AVE_RXCR_RXEN, priv->base + AVE_RXCR);
                /* change and enable TX/Rx mac */
                writel(txcr, priv->base + AVE_TXCR);
                writel(rxcr, priv->base + AVE_RXCR);
        }

        phy_print_status(phydev);
}

static void ave_macaddr_init(struct net_device *ndev)
{
        ave_hw_write_macaddr(ndev, ndev->dev_addr, AVE_RXMAC1R, AVE_RXMAC2R);

        /* pfsel unicast entry */
        ave_pfsel_set_macaddr(ndev, AVE_PFNUM_UNICAST, ndev->dev_addr, 6);
}

static int ave_init(struct net_device *ndev)
{
        struct ethtool_wolinfo wol = { .cmd = ETHTOOL_GWOL };
        struct ave_private *priv = netdev_priv(ndev);
        struct device *dev = ndev->dev.parent;
        struct device_node *np = dev->of_node;
        struct device_node *mdio_np;
        struct phy_device *phydev;
        int nc, nr, ret;

        /* enable clk because of hw access until ndo_open */
        for (nc = 0; nc < priv->nclks; nc++) {
                ret = clk_prepare_enable(priv->clk[nc]);
                if (ret) {
                        dev_err(dev, "can't enable clock\n");
                        goto out_clk_disable;
                }
        }

        for (nr = 0; nr < priv->nrsts; nr++) {
                ret = reset_control_deassert(priv->rst[nr]);
                if (ret) {
                        dev_err(dev, "can't deassert reset\n");
                        goto out_reset_assert;
                }
        }

        ret = regmap_update_bits(priv->regmap, SG_ETPINMODE,
                                 priv->pinmode_mask, priv->pinmode_val);
        if (ret)
                return ret;

        ave_global_reset(ndev);

        mdio_np = of_get_child_by_name(np, "mdio");
        if (!mdio_np) {
                dev_err(dev, "mdio node not found\n");
                ret = -EINVAL;
                goto out_reset_assert;
        }
        ret = of_mdiobus_register(priv->mdio, mdio_np);
        of_node_put(mdio_np);
        if (ret) {
                dev_err(dev, "failed to register mdiobus\n");
                goto out_reset_assert;
        }

        phydev = of_phy_get_and_connect(ndev, np, ave_phy_adjust_link);
        if (!phydev) {
                dev_err(dev, "could not attach to PHY\n");
                ret = -ENODEV;
                goto out_mdio_unregister;
        }

        priv->phydev = phydev;

        ave_ethtool_get_wol(ndev, &wol);
        device_set_wakeup_capable(&ndev->dev, !!wol.supported);

        /* set wol initial state disabled */
        wol.wolopts = 0;
        ave_ethtool_set_wol(ndev, &wol);

        if (!phy_interface_is_rgmii(phydev))
                phy_set_max_speed(phydev, SPEED_100);

        phy_support_asym_pause(phydev);

        phy_attached_info(phydev);

        return 0;

out_mdio_unregister:
        mdiobus_unregister(priv->mdio);
out_reset_assert:
        while (--nr >= 0)
                reset_control_assert(priv->rst[nr]);
out_clk_disable:
        while (--nc >= 0)
                clk_disable_unprepare(priv->clk[nc]);

        return ret;
}

static void ave_uninit(struct net_device *ndev)
{
        struct ave_private *priv = netdev_priv(ndev);
        int i;

        phy_disconnect(priv->phydev);
        mdiobus_unregister(priv->mdio);

        /* disable clk because of hw access after ndo_stop */
        for (i = 0; i < priv->nrsts; i++)
                reset_control_assert(priv->rst[i]);
        for (i = 0; i < priv->nclks; i++)
                clk_disable_unprepare(priv->clk[i]);
}

static int ave_open(struct net_device *ndev)
{
        struct ave_private *priv = netdev_priv(ndev);
        int entry;
        int ret;
        u32 val;

        ret = request_irq(priv->irq, ave_irq_handler, IRQF_SHARED, ndev->name,
                          ndev);
        if (ret)
                return ret;

        priv->tx.desc = kcalloc(priv->tx.ndesc, sizeof(*priv->tx.desc),
                                GFP_KERNEL);
        if (!priv->tx.desc) {
                ret = -ENOMEM;
                goto out_free_irq;
        }

        priv->rx.desc = kcalloc(priv->rx.ndesc, sizeof(*priv->rx.desc),
                                GFP_KERNEL);
        if (!priv->rx.desc) {
                kfree(priv->tx.desc);
                ret = -ENOMEM;
                goto out_free_irq;
        }

        /* initialize Tx work and descriptor */
        priv->tx.proc_idx = 0;
        priv->tx.done_idx = 0;
        for (entry = 0; entry < priv->tx.ndesc; entry++) {
                ave_desc_write_cmdsts(ndev, AVE_DESCID_TX, entry, 0);
                ave_desc_write_addr(ndev, AVE_DESCID_TX, entry, 0);
        }
        writel(AVE_TXDC_ADDR_START |
               (((priv->tx.ndesc * priv->desc_size) << 16) & AVE_TXDC_SIZE),
               priv->base + AVE_TXDC);

        /* initialize Rx work and descriptor */
        priv->rx.proc_idx = 0;
        priv->rx.done_idx = 0;
        for (entry = 0; entry < priv->rx.ndesc; entry++) {
                if (ave_rxdesc_prepare(ndev, entry))
                        break;
        }
        writel(AVE_RXDC0_ADDR_START |
               (((priv->rx.ndesc * priv->desc_size) << 16) & AVE_RXDC0_SIZE),
               priv->base + AVE_RXDC0);

        ave_desc_switch(ndev, AVE_DESC_START);

        ave_pfsel_init(ndev);
        ave_macaddr_init(ndev);

        /* set Rx configuration */
        /* full duplex, enable pause drop, enalbe flow control */
        val = AVE_RXCR_RXEN | AVE_RXCR_FDUPEN | AVE_RXCR_DRPEN |
                AVE_RXCR_FLOCTR | (AVE_MAX_ETHFRAME & AVE_RXCR_MPSIZ_MASK);
        writel(val, priv->base + AVE_RXCR);

        /* set Tx configuration */
        /* enable flow control, disable loopback */
        writel(AVE_TXCR_FLOCTR, priv->base + AVE_TXCR);

        /* enable timer, clear EN,INTM, and mask interval unit(BSCK) */
        val = readl(priv->base + AVE_IIRQC) & AVE_IIRQC_BSCK;
        val |= AVE_IIRQC_EN0 | (AVE_INTM_COUNT << 16);
        writel(val, priv->base + AVE_IIRQC);

        val = AVE_GI_RXIINT | AVE_GI_RXOVF | AVE_GI_TX | AVE_GI_RXDROP;
        ave_irq_restore(ndev, val);

        napi_enable(&priv->napi_rx);
        napi_enable(&priv->napi_tx);

        phy_start(ndev->phydev);
        phy_start_aneg(ndev->phydev);
        netif_start_queue(ndev);

        return 0;

out_free_irq:
        disable_irq(priv->irq);
        free_irq(priv->irq, ndev);

        return ret;
}

static int ave_stop(struct net_device *ndev)
{
        struct ave_private *priv = netdev_priv(ndev);
        int entry;

        ave_irq_disable_all(ndev);
        disable_irq(priv->irq);
        free_irq(priv->irq, ndev);

        netif_tx_disable(ndev);
        phy_stop(ndev->phydev);
        napi_disable(&priv->napi_tx);
        napi_disable(&priv->napi_rx);

        ave_desc_switch(ndev, AVE_DESC_STOP);

        /* free Tx buffer */
        for (entry = 0; entry < priv->tx.ndesc; entry++) {
                if (!priv->tx.desc[entry].skbs)
                        continue;

                ave_dma_unmap(ndev, &priv->tx.desc[entry], DMA_TO_DEVICE);
                dev_kfree_skb_any(priv->tx.desc[entry].skbs);
                priv->tx.desc[entry].skbs = NULL;
        }
        priv->tx.proc_idx = 0;
        priv->tx.done_idx = 0;

        /* free Rx buffer */
        for (entry = 0; entry < priv->rx.ndesc; entry++) {
                if (!priv->rx.desc[entry].skbs)
                        continue;

                ave_dma_unmap(ndev, &priv->rx.desc[entry], DMA_FROM_DEVICE);
                dev_kfree_skb_any(priv->rx.desc[entry].skbs);
                priv->rx.desc[entry].skbs = NULL;
        }
        priv->rx.proc_idx = 0;
        priv->rx.done_idx = 0;

        kfree(priv->tx.desc);
        kfree(priv->rx.desc);

        return 0;
}

static int ave_start_xmit(struct sk_buff *skb, struct net_device *ndev)
{
        struct ave_private *priv = netdev_priv(ndev);
        u32 proc_idx, done_idx, ndesc, cmdsts;
        int ret, freepkt;
        dma_addr_t paddr;

        proc_idx = priv->tx.proc_idx;
        done_idx = priv->tx.done_idx;
        ndesc = priv->tx.ndesc;
        freepkt = ((done_idx + ndesc - 1) - proc_idx) % ndesc;

        /* stop queue when not enough entry */
        if (unlikely(freepkt < 1)) {
                netif_stop_queue(ndev);
                return NETDEV_TX_BUSY;
        }

        /* add padding for short packet */
        if (skb_put_padto(skb, ETH_ZLEN)) {
                priv->stats_tx.dropped++;
                return NETDEV_TX_OK;
        }

        /* map Tx buffer
         * Tx buffer set to the Tx descriptor doesn't have any restriction.
         */
        ret = ave_dma_map(ndev, &priv->tx.desc[proc_idx],
                          skb->data, skb->len, DMA_TO_DEVICE, &paddr);
        if (ret) {
                dev_kfree_skb_any(skb);
                priv->stats_tx.dropped++;
                return NETDEV_TX_OK;
        }

        priv->tx.desc[proc_idx].skbs = skb;

        ave_desc_write_addr(ndev, AVE_DESCID_TX, proc_idx, paddr);

        cmdsts = AVE_STS_OWN | AVE_STS_1ST | AVE_STS_LAST |
                (skb->len & AVE_STS_PKTLEN_TX_MASK);

        /* set interrupt per AVE_FORCE_TXINTCNT or when queue is stopped */
        if (!(proc_idx % AVE_FORCE_TXINTCNT) || netif_queue_stopped(ndev))
                cmdsts |= AVE_STS_INTR;

        /* disable checksum calculation when skb doesn't calurate checksum */
        if (skb->ip_summed == CHECKSUM_NONE ||
            skb->ip_summed == CHECKSUM_UNNECESSARY)
                cmdsts |= AVE_STS_NOCSUM;

        ave_desc_write_cmdsts(ndev, AVE_DESCID_TX, proc_idx, cmdsts);

        priv->tx.proc_idx = (proc_idx + 1) % ndesc;

        return NETDEV_TX_OK;
}

static int ave_ioctl(struct net_device *ndev, struct ifreq *ifr, int cmd)
{
        return phy_mii_ioctl(ndev->phydev, ifr, cmd);
}

static const u8 v4multi_macadr[] = { 0x01, 0x00, 0x00, 0x00, 0x00, 0x00 };
static const u8 v6multi_macadr[] = { 0x33, 0x00, 0x00, 0x00, 0x00, 0x00 };

static void ave_set_rx_mode(struct net_device *ndev)
{
        struct ave_private *priv = netdev_priv(ndev);
        struct netdev_hw_addr *hw_adr;
        int count, mc_cnt;
        u32 val;

        /* MAC addr filter enable for promiscious mode */
        mc_cnt = netdev_mc_count(ndev);
        val = readl(priv->base + AVE_RXCR);
        if (ndev->flags & IFF_PROMISC || !mc_cnt)
                val &= ~AVE_RXCR_AFEN;
        else
                val |= AVE_RXCR_AFEN;
        writel(val, priv->base + AVE_RXCR);

        /* set all multicast address */
        if ((ndev->flags & IFF_ALLMULTI) || mc_cnt > AVE_PF_MULTICAST_SIZE) {
                ave_pfsel_set_macaddr(ndev, AVE_PFNUM_MULTICAST,
                                      v4multi_macadr, 1);
                ave_pfsel_set_macaddr(ndev, AVE_PFNUM_MULTICAST + 1,
                                      v6multi_macadr, 1);
        } else {
                /* stop all multicast filter */
                for (count = 0; count < AVE_PF_MULTICAST_SIZE; count++)
                        ave_pfsel_stop(ndev, AVE_PFNUM_MULTICAST + count);

                /* set multicast addresses */
                count = 0;
                netdev_for_each_mc_addr(hw_adr, ndev) {
                        if (count == mc_cnt)
                                break;
                        ave_pfsel_set_macaddr(ndev, AVE_PFNUM_MULTICAST + count,
                                              hw_adr->addr, 6);
                        count++;
                }
        }
}

static void ave_get_stats64(struct net_device *ndev,
                            struct rtnl_link_stats64 *stats)
{
        struct ave_private *priv = netdev_priv(ndev);
        unsigned int start;

        do {
                start = u64_stats_fetch_begin_irq(&priv->stats_rx.syncp);
                stats->rx_packets = priv->stats_rx.packets;
                stats->rx_bytes   = priv->stats_rx.bytes;
        } while (u64_stats_fetch_retry_irq(&priv->stats_rx.syncp, start));

        do {
                start = u64_stats_fetch_begin_irq(&priv->stats_tx.syncp);
                stats->tx_packets = priv->stats_tx.packets;
                stats->tx_bytes   = priv->stats_tx.bytes;
        } while (u64_stats_fetch_retry_irq(&priv->stats_tx.syncp, start));

        stats->rx_errors      = priv->stats_rx.errors;
        stats->tx_errors      = priv->stats_tx.errors;
        stats->rx_dropped     = priv->stats_rx.dropped;
        stats->tx_dropped     = priv->stats_tx.dropped;
        stats->rx_fifo_errors = priv->stats_rx.fifo_errors;
        stats->collisions     = priv->stats_tx.collisions;
}

static int ave_set_mac_address(struct net_device *ndev, void *p)
{
        int ret = eth_mac_addr(ndev, p);

        if (ret)
                return ret;

        ave_macaddr_init(ndev);

        return 0;
}

static const struct net_device_ops ave_netdev_ops = {
        .ndo_init               = ave_init,
        .ndo_uninit             = ave_uninit,
        .ndo_open               = ave_open,
        .ndo_stop               = ave_stop,
        .ndo_start_xmit         = ave_start_xmit,
        .ndo_do_ioctl           = ave_ioctl,
        .ndo_set_rx_mode        = ave_set_rx_mode,
        .ndo_get_stats64        = ave_get_stats64,
        .ndo_set_mac_address    = ave_set_mac_address,
};

static int ave_probe(struct platform_device *pdev)
{
        const struct ave_soc_data *data;
        struct device *dev = &pdev->dev;
        char buf[ETHTOOL_FWVERS_LEN];
        struct of_phandle_args args;
        phy_interface_t phy_mode;
        struct ave_private *priv;
        struct net_device *ndev;
        struct device_node *np;
        struct resource *res;
        const void *mac_addr;
        void __iomem *base;
        const char *name;
        int i, irq, ret;
        u64 dma_mask;
        u32 ave_id;

        data = of_device_get_match_data(dev);
        if (WARN_ON(!data))
                return -EINVAL;

        np = dev->of_node;
        phy_mode = of_get_phy_mode(np);
        if (phy_mode < 0) {
                dev_err(dev, "phy-mode not found\n");
                return -EINVAL;
        }

        irq = platform_get_irq(pdev, 0);
        if (irq < 0) {
                dev_err(dev, "IRQ not found\n");
                return irq;
        }

        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        base = devm_ioremap_resource(dev, res);
        if (IS_ERR(base))
                return PTR_ERR(base);

        ndev = alloc_etherdev(sizeof(struct ave_private));
        if (!ndev) {
                dev_err(dev, "can't allocate ethernet device\n");
                return -ENOMEM;
        }

        ndev->netdev_ops = &ave_netdev_ops;
        ndev->ethtool_ops = &ave_ethtool_ops;
        SET_NETDEV_DEV(ndev, dev);

        ndev->features    |= (NETIF_F_IP_CSUM | NETIF_F_RXCSUM);
        ndev->hw_features |= (NETIF_F_IP_CSUM | NETIF_F_RXCSUM);

        ndev->max_mtu = AVE_MAX_ETHFRAME - (ETH_HLEN + ETH_FCS_LEN);

        mac_addr = of_get_mac_address(np);
        if (!IS_ERR(mac_addr))
                ether_addr_copy(ndev->dev_addr, mac_addr);

        /* if the mac address is invalid, use random mac address */
        if (!is_valid_ether_addr(ndev->dev_addr)) {
                eth_hw_addr_random(ndev);
                dev_warn(dev, "Using random MAC address: %pM\n",
                         ndev->dev_addr);
        }

        priv = netdev_priv(ndev);
        priv->base = base;
        priv->irq = irq;
        priv->ndev = ndev;
        priv->msg_enable = netif_msg_init(-1, AVE_DEFAULT_MSG_ENABLE);
        priv->phy_mode = phy_mode;
        priv->data = data;

        if (IS_DESC_64BIT(priv)) {
                priv->desc_size = AVE_DESC_SIZE_64;
                priv->tx.daddr  = AVE_TXDM_64;
                priv->rx.daddr  = AVE_RXDM_64;
                dma_mask = DMA_BIT_MASK(64);
        } else {
                priv->desc_size = AVE_DESC_SIZE_32;
                priv->tx.daddr  = AVE_TXDM_32;
                priv->rx.daddr  = AVE_RXDM_32;
                dma_mask = DMA_BIT_MASK(32);
        }
        ret = dma_set_mask(dev, dma_mask);
        if (ret)
                goto out_free_netdev;

        priv->tx.ndesc = AVE_NR_TXDESC;
        priv->rx.ndesc = AVE_NR_RXDESC;

        u64_stats_init(&priv->stats_tx.syncp);
        u64_stats_init(&priv->stats_rx.syncp);

        for (i = 0; i < AVE_MAX_CLKS; i++) {
                name = priv->data->clock_names[i];
                if (!name)
                        break;
                priv->clk[i] = devm_clk_get(dev, name);
                if (IS_ERR(priv->clk[i])) {
                        ret = PTR_ERR(priv->clk[i]);
                        goto out_free_netdev;
                }
                priv->nclks++;
        }

        for (i = 0; i < AVE_MAX_RSTS; i++) {
                name = priv->data->reset_names[i];
                if (!name)
                        break;
                priv->rst[i] = devm_reset_control_get_shared(dev, name);
                if (IS_ERR(priv->rst[i])) {
                        ret = PTR_ERR(priv->rst[i]);
                        goto out_free_netdev;
                }
                priv->nrsts++;
        }

        ret = of_parse_phandle_with_fixed_args(np,
                                               "socionext,syscon-phy-mode",
                                               1, 0, &args);
        if (ret) {
                netdev_err(ndev, "can't get syscon-phy-mode property\n");
                goto out_free_netdev;
        }
        priv->regmap = syscon_node_to_regmap(args.np);
        of_node_put(args.np);
        if (IS_ERR(priv->regmap)) {
                netdev_err(ndev, "can't map syscon-phy-mode\n");
                ret = PTR_ERR(priv->regmap);
                goto out_free_netdev;
        }
        ret = priv->data->get_pinmode(priv, phy_mode, args.args[0]);
        if (ret) {
                netdev_err(ndev, "invalid phy-mode setting\n");
                goto out_free_netdev;
        }

        priv->mdio = devm_mdiobus_alloc(dev);
        if (!priv->mdio) {
                ret = -ENOMEM;
                goto out_free_netdev;
        }
        priv->mdio->priv = ndev;
        priv->mdio->parent = dev;
        priv->mdio->read = ave_mdiobus_read;
        priv->mdio->write = ave_mdiobus_write;
        priv->mdio->name = "uniphier-mdio";
        snprintf(priv->mdio->id, MII_BUS_ID_SIZE, "%s-%x",
                 pdev->name, pdev->id);

        /* Register as a NAPI supported driver */
        netif_napi_add(ndev, &priv->napi_rx, ave_napi_poll_rx,
                       NAPI_POLL_WEIGHT);
        netif_tx_napi_add(ndev, &priv->napi_tx, ave_napi_poll_tx,
                          NAPI_POLL_WEIGHT);

        platform_set_drvdata(pdev, ndev);

        ret = register_netdev(ndev);
        if (ret) {
                dev_err(dev, "failed to register netdevice\n");
                goto out_del_napi;
        }

        /* get ID and version */
        ave_id = readl(priv->base + AVE_IDR);
        ave_hw_read_version(ndev, buf, sizeof(buf));

        dev_info(dev, "Socionext %c%c%c%c Ethernet IP %s (irq=%d, phy=%s)\n",
                 (ave_id >> 24) & 0xff, (ave_id >> 16) & 0xff,
                 (ave_id >> 8) & 0xff, (ave_id >> 0) & 0xff,
                 buf, priv->irq, phy_modes(phy_mode));

        return 0;

out_del_napi:
        netif_napi_del(&priv->napi_rx);
        netif_napi_del(&priv->napi_tx);
out_free_netdev:
        free_netdev(ndev);

        return ret;
}

static int ave_remove(struct platform_device *pdev)
{
        struct net_device *ndev = platform_get_drvdata(pdev);
        struct ave_private *priv = netdev_priv(ndev);

        unregister_netdev(ndev);
        netif_napi_del(&priv->napi_rx);
        netif_napi_del(&priv->napi_tx);
        free_netdev(ndev);

        return 0;
}

#ifdef CONFIG_PM_SLEEP
static int ave_suspend(struct device *dev)
{
        struct ethtool_wolinfo wol = { .cmd = ETHTOOL_GWOL };
        struct net_device *ndev = dev_get_drvdata(dev);
        struct ave_private *priv = netdev_priv(ndev);
        int ret = 0;

        if (netif_running(ndev)) {
                ret = ave_stop(ndev);
                netif_device_detach(ndev);
        }

        ave_ethtool_get_wol(ndev, &wol);
        priv->wolopts = wol.wolopts;

        return ret;
}

static int ave_resume(struct device *dev)
{
        struct ethtool_wolinfo wol = { .cmd = ETHTOOL_GWOL };
        struct net_device *ndev = dev_get_drvdata(dev);
        struct ave_private *priv = netdev_priv(ndev);
        int ret = 0;

        ave_global_reset(ndev);

        ave_ethtool_get_wol(ndev, &wol);
        wol.wolopts = priv->wolopts;
        ave_ethtool_set_wol(ndev, &wol);

        if (ndev->phydev) {
                ret = phy_resume(ndev->phydev);
                if (ret)
                        return ret;
        }

        if (netif_running(ndev)) {
                ret = ave_open(ndev);
                netif_device_attach(ndev);
        }

        return ret;
}

static SIMPLE_DEV_PM_OPS(ave_pm_ops, ave_suspend, ave_resume);
#define AVE_PM_OPS      (&ave_pm_ops)
#else
#define AVE_PM_OPS      NULL
#endif

static int ave_pro4_get_pinmode(struct ave_private *priv,
                                phy_interface_t phy_mode, u32 arg)
{
        if (arg > 0)
                return -EINVAL;

        priv->pinmode_mask = SG_ETPINMODE_RMII(0);

        switch (phy_mode) {
        case PHY_INTERFACE_MODE_RMII:
                priv->pinmode_val = SG_ETPINMODE_RMII(0);
                break;
        case PHY_INTERFACE_MODE_MII:
        case PHY_INTERFACE_MODE_RGMII:
                priv->pinmode_val = 0;
                break;
        default:
                return -EINVAL;
        }

        return 0;
}

static int ave_ld11_get_pinmode(struct ave_private *priv,
                                phy_interface_t phy_mode, u32 arg)
{
        if (arg > 0)
                return -EINVAL;

        priv->pinmode_mask = SG_ETPINMODE_EXTPHY | SG_ETPINMODE_RMII(0);

        switch (phy_mode) {
        case PHY_INTERFACE_MODE_INTERNAL:
                priv->pinmode_val = 0;
                break;
        case PHY_INTERFACE_MODE_RMII:
                priv->pinmode_val = SG_ETPINMODE_EXTPHY | SG_ETPINMODE_RMII(0);
                break;
        default:
                return -EINVAL;
        }

        return 0;
}

static int ave_ld20_get_pinmode(struct ave_private *priv,
                                phy_interface_t phy_mode, u32 arg)
{
        if (arg > 0)
                return -EINVAL;

        priv->pinmode_mask = SG_ETPINMODE_RMII(0);

        switch (phy_mode) {
        case PHY_INTERFACE_MODE_RMII:
                priv->pinmode_val = SG_ETPINMODE_RMII(0);
                break;
        case PHY_INTERFACE_MODE_RGMII:
                priv->pinmode_val = 0;
                break;
        default:
                return -EINVAL;
        }

        return 0;
}

static int ave_pxs3_get_pinmode(struct ave_private *priv,
                                phy_interface_t phy_mode, u32 arg)
{
        if (arg > 1)
                return -EINVAL;

        priv->pinmode_mask = SG_ETPINMODE_RMII(arg);

        switch (phy_mode) {
        case PHY_INTERFACE_MODE_RMII:
                priv->pinmode_val = SG_ETPINMODE_RMII(arg);
                break;
        case PHY_INTERFACE_MODE_RGMII:
                priv->pinmode_val = 0;
                break;
        default:
                return -EINVAL;
        }

        return 0;
}

static const struct ave_soc_data ave_pro4_data = {
        .is_desc_64bit = false,
        .clock_names = {
                "gio", "ether", "ether-gb", "ether-phy",
        },
        .reset_names = {
                "gio", "ether",
        },
        .get_pinmode = ave_pro4_get_pinmode,
};

static const struct ave_soc_data ave_pxs2_data = {
        .is_desc_64bit = false,
        .clock_names = {
                "ether",
        },
        .reset_names = {
                "ether",
        },
        .get_pinmode = ave_pro4_get_pinmode,
};

static const struct ave_soc_data ave_ld11_data = {
        .is_desc_64bit = false,
        .clock_names = {
                "ether",
        },
        .reset_names = {
                "ether",
        },
        .get_pinmode = ave_ld11_get_pinmode,
};

static const struct ave_soc_data ave_ld20_data = {
        .is_desc_64bit = true,
        .clock_names = {
                "ether",
        },
        .reset_names = {
                "ether",
        },
        .get_pinmode = ave_ld20_get_pinmode,
};

static const struct ave_soc_data ave_pxs3_data = {
        .is_desc_64bit = false,
        .clock_names = {
                "ether",
        },
        .reset_names = {
                "ether",
        },
        .get_pinmode = ave_pxs3_get_pinmode,
};

static const struct of_device_id of_ave_match[] = {
        {
                .compatible = "socionext,uniphier-pro4-ave4",
                .data = &ave_pro4_data,
        },
        {
                .compatible = "socionext,uniphier-pxs2-ave4",
                .data = &ave_pxs2_data,
        },
        {
                .compatible = "socionext,uniphier-ld11-ave4",
                .data = &ave_ld11_data,
        },
        {
                .compatible = "socionext,uniphier-ld20-ave4",
                .data = &ave_ld20_data,
        },
        {
                .compatible = "socionext,uniphier-pxs3-ave4",
                .data = &ave_pxs3_data,
        },
        { /* Sentinel */ }
};
MODULE_DEVICE_TABLE(of, of_ave_match);

static struct platform_driver ave_driver = {
        .probe  = ave_probe,
        .remove = ave_remove,
        .driver = {
                .name = "ave",
                .pm   = AVE_PM_OPS,
                .of_match_table = of_ave_match,
        },
};
module_platform_driver(ave_driver);

MODULE_AUTHOR("Kunihiko Hayashi <hayashi.kunihiko@socionext.com>");
MODULE_DESCRIPTION("Socionext UniPhier AVE ethernet driver");
MODULE_LICENSE("GPL v2");