// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * PXA168 ethernet driver.
 * Most of the code is derived from mv643xx ethernet driver.
 *
 * Copyright (C) 2010 Marvell International Ltd.
 *              Sachin Sanap <ssanap@marvell.com>
 *              Zhangfei Gao <zgao6@marvell.com>
 *              Philip Rakity <prakity@marvell.com>
 *              Mark Brown <markb@marvell.com>
 */

#include <linux/bitops.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/dma-mapping.h>
#include <linux/etherdevice.h>
#include <linux/ethtool.h>
#include <linux/in.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/ip.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_net.h>
#include <linux/phy.h>
#include <linux/platform_device.h>
#include <linux/pxa168_eth.h>
#include <linux/tcp.h>
#include <linux/types.h>
#include <linux/udp.h>
#include <linux/workqueue.h>
#include <linux/pgtable.h>

#include <asm/cacheflush.h>

#define DRIVER_NAME     "pxa168-eth"
#define DRIVER_VERSION  "0.3"

/*
 * Registers
 */

#define PHY_ADDRESS             0x0000
#define SMI                     0x0010
#define PORT_CONFIG             0x0400
#define PORT_CONFIG_EXT         0x0408
#define PORT_COMMAND            0x0410
#define PORT_STATUS             0x0418
#define HTPR                    0x0428
#define MAC_ADDR_LOW            0x0430
#define MAC_ADDR_HIGH           0x0438
#define SDMA_CONFIG             0x0440
#define SDMA_CMD                0x0448
#define INT_CAUSE               0x0450
#define INT_W_CLEAR             0x0454
#define INT_MASK                0x0458
#define ETH_F_RX_DESC_0         0x0480
#define ETH_C_RX_DESC_0         0x04A0
#define ETH_C_TX_DESC_1         0x04E4

/* smi register */
#define SMI_BUSY                (1 << 28)       /* 0 - Write, 1 - Read  */
#define SMI_R_VALID             (1 << 27)       /* 0 - Write, 1 - Read  */
#define SMI_OP_W                (0 << 26)       /* Write operation      */
#define SMI_OP_R                (1 << 26)       /* Read operation */

#define PHY_WAIT_ITERATIONS     10

#define PXA168_ETH_PHY_ADDR_DEFAULT     0
/* RX & TX descriptor command */
#define BUF_OWNED_BY_DMA        (1 << 31)

/* RX descriptor status */
#define RX_EN_INT               (1 << 23)
#define RX_FIRST_DESC           (1 << 17)
#define RX_LAST_DESC            (1 << 16)
#define RX_ERROR                (1 << 15)

/* TX descriptor command */
#define TX_EN_INT               (1 << 23)
#define TX_GEN_CRC              (1 << 22)
#define TX_ZERO_PADDING         (1 << 18)
#define TX_FIRST_DESC           (1 << 17)
#define TX_LAST_DESC            (1 << 16)
#define TX_ERROR                (1 << 15)

/* SDMA_CMD */
#define SDMA_CMD_AT             (1 << 31)
#define SDMA_CMD_TXDL           (1 << 24)
#define SDMA_CMD_TXDH           (1 << 23)
#define SDMA_CMD_AR             (1 << 15)
#define SDMA_CMD_ERD            (1 << 7)

/* Bit definitions of the Port Config Reg */
#define PCR_DUPLEX_FULL         (1 << 15)
#define PCR_HS                  (1 << 12)
#define PCR_EN                  (1 << 7)
#define PCR_PM                  (1 << 0)

/* Bit definitions of the Port Config Extend Reg */
#define PCXR_2BSM               (1 << 28)
#define PCXR_DSCP_EN            (1 << 21)
#define PCXR_RMII_EN            (1 << 20)
#define PCXR_AN_SPEED_DIS       (1 << 19)
#define PCXR_SPEED_100          (1 << 18)
#define PCXR_MFL_1518           (0 << 14)
#define PCXR_MFL_1536           (1 << 14)
#define PCXR_MFL_2048           (2 << 14)
#define PCXR_MFL_64K            (3 << 14)
#define PCXR_FLOWCTL_DIS        (1 << 12)
#define PCXR_FLP                (1 << 11)
#define PCXR_AN_FLOWCTL_DIS     (1 << 10)
#define PCXR_AN_DUPLEX_DIS      (1 << 9)
#define PCXR_PRIO_TX_OFF        3
#define PCXR_TX_HIGH_PRI        (7 << PCXR_PRIO_TX_OFF)

/* Bit definitions of the SDMA Config Reg */
#define SDCR_BSZ_OFF            12
#define SDCR_BSZ8               (3 << SDCR_BSZ_OFF)
#define SDCR_BSZ4               (2 << SDCR_BSZ_OFF)
#define SDCR_BSZ2               (1 << SDCR_BSZ_OFF)
#define SDCR_BSZ1               (0 << SDCR_BSZ_OFF)
#define SDCR_BLMR               (1 << 6)
#define SDCR_BLMT               (1 << 7)
#define SDCR_RIFB               (1 << 9)
#define SDCR_RC_OFF             2
#define SDCR_RC_MAX_RETRANS     (0xf << SDCR_RC_OFF)

/*
 * Bit definitions of the Interrupt Cause Reg
 * and Interrupt MASK Reg is the same
 */
#define ICR_RXBUF               (1 << 0)
#define ICR_TXBUF_H             (1 << 2)
#define ICR_TXBUF_L             (1 << 3)
#define ICR_TXEND_H             (1 << 6)
#define ICR_TXEND_L             (1 << 7)
#define ICR_RXERR               (1 << 8)
#define ICR_TXERR_H             (1 << 10)
#define ICR_TXERR_L             (1 << 11)
#define ICR_TX_UDR              (1 << 13)
#define ICR_MII_CH              (1 << 28)

#define ALL_INTS (ICR_TXBUF_H  | ICR_TXBUF_L  | ICR_TX_UDR |\
                                ICR_TXERR_H  | ICR_TXERR_L |\
                                ICR_TXEND_H  | ICR_TXEND_L |\
                                ICR_RXBUF | ICR_RXERR  | ICR_MII_CH)

#define ETH_HW_IP_ALIGN         2       /* hw aligns IP header */

#define NUM_RX_DESCS            64
#define NUM_TX_DESCS            64

#define HASH_ADD                0
#define HASH_DELETE             1
#define HASH_ADDR_TABLE_SIZE    0x4000  /* 16K (1/2K address - PCR_HS == 1) */
#define HOP_NUMBER              12

/* Bit definitions for Port status */
#define PORT_SPEED_100          (1 << 0)
#define FULL_DUPLEX             (1 << 1)
#define FLOW_CONTROL_DISABLED   (1 << 2)
#define LINK_UP                 (1 << 3)

/* Bit definitions for work to be done */
#define WORK_TX_DONE            (1 << 1)

/*
 * Misc definitions.
 */
#define SKB_DMA_REALIGN         ((PAGE_SIZE - NET_SKB_PAD) % SMP_CACHE_BYTES)

struct rx_desc {
        u32 cmd_sts;            /* Descriptor command status            */
        u16 byte_cnt;           /* Descriptor buffer byte count         */
        u16 buf_size;           /* Buffer size                          */
        u32 buf_ptr;            /* Descriptor buffer pointer            */
        u32 next_desc_ptr;      /* Next descriptor pointer              */
};

struct tx_desc {
        u32 cmd_sts;            /* Command/status field                 */
        u16 reserved;
        u16 byte_cnt;           /* buffer byte count                    */
        u32 buf_ptr;            /* pointer to buffer for this descriptor */
        u32 next_desc_ptr;      /* Pointer to next descriptor           */
};

struct pxa168_eth_private {
        struct platform_device *pdev;
        int port_num;           /* User Ethernet port number    */
        int phy_addr;
        int phy_speed;
        int phy_duplex;
        phy_interface_t phy_intf;

        int rx_resource_err;    /* Rx ring resource error flag */

        /* Next available and first returning Rx resource */
        int rx_curr_desc_q, rx_used_desc_q;

        /* Next available and first returning Tx resource */
        int tx_curr_desc_q, tx_used_desc_q;

        struct rx_desc *p_rx_desc_area;
        dma_addr_t rx_desc_dma;
        int rx_desc_area_size;
        struct sk_buff **rx_skb;

        struct tx_desc *p_tx_desc_area;
        dma_addr_t tx_desc_dma;
        int tx_desc_area_size;
        struct sk_buff **tx_skb;

        struct work_struct tx_timeout_task;

        struct net_device *dev;
        struct napi_struct napi;
        u8 work_todo;
        int skb_size;

        /* Size of Tx Ring per queue */
        int tx_ring_size;
        /* Number of tx descriptors in use */
        int tx_desc_count;
        /* Size of Rx Ring per queue */
        int rx_ring_size;
        /* Number of rx descriptors in use */
        int rx_desc_count;

        /*
         * Used in case RX Ring is empty, which can occur when
         * system does not have resources (skb's)
         */
        struct timer_list timeout;
        struct mii_bus *smi_bus;

        /* clock */
        struct clk *clk;
        struct pxa168_eth_platform_data *pd;
        /*
         * Ethernet controller base address.
         */
        void __iomem *base;

        /* Pointer to the hardware address filter table */
        void *htpr;
        dma_addr_t htpr_dma;
};

struct addr_table_entry {
        __le32 lo;
        __le32 hi;
};

/* Bit fields of a Hash Table Entry */
enum hash_table_entry {
        HASH_ENTRY_VALID = 1,
        SKIP = 2,
        HASH_ENTRY_RECEIVE_DISCARD = 4,
        HASH_ENTRY_RECEIVE_DISCARD_BIT = 2
};

static int pxa168_init_hw(struct pxa168_eth_private *pep);
static int pxa168_init_phy(struct net_device *dev);
static void eth_port_reset(struct net_device *dev);
static void eth_port_start(struct net_device *dev);
static int pxa168_eth_open(struct net_device *dev);
static int pxa168_eth_stop(struct net_device *dev);

static inline u32 rdl(struct pxa168_eth_private *pep, int offset)
{
        return readl_relaxed(pep->base + offset);
}

static inline void wrl(struct pxa168_eth_private *pep, int offset, u32 data)
{
        writel_relaxed(data, pep->base + offset);
}

static void abort_dma(struct pxa168_eth_private *pep)
{
        int delay;
        int max_retries = 40;

        do {
                wrl(pep, SDMA_CMD, SDMA_CMD_AR | SDMA_CMD_AT);
                udelay(100);

                delay = 10;
                while ((rdl(pep, SDMA_CMD) & (SDMA_CMD_AR | SDMA_CMD_AT))
                       && delay-- > 0) {
                        udelay(10);
                }
        } while (max_retries-- > 0 && delay <= 0);

        if (max_retries <= 0)
                netdev_err(pep->dev, "%s : DMA Stuck\n", __func__);
}

static void rxq_refill(struct net_device *dev)
{
        struct pxa168_eth_private *pep = netdev_priv(dev);
        struct sk_buff *skb;
        struct rx_desc *p_used_rx_desc;
        int used_rx_desc;

        while (pep->rx_desc_count < pep->rx_ring_size) {
                int size;

                skb = netdev_alloc_skb(dev, pep->skb_size);
                if (!skb)
                        break;
                if (SKB_DMA_REALIGN)
                        skb_reserve(skb, SKB_DMA_REALIGN);
                pep->rx_desc_count++;
                /* Get 'used' Rx descriptor */
                used_rx_desc = pep->rx_used_desc_q;
                p_used_rx_desc = &pep->p_rx_desc_area[used_rx_desc];
                size = skb_end_pointer(skb) - skb->data;
                p_used_rx_desc->buf_ptr = dma_map_single(&pep->pdev->dev,
                                                         skb->data,
                                                         size,
                                                         DMA_FROM_DEVICE);
                p_used_rx_desc->buf_size = size;
                pep->rx_skb[used_rx_desc] = skb;

                /* Return the descriptor to DMA ownership */
                dma_wmb();
                p_used_rx_desc->cmd_sts = BUF_OWNED_BY_DMA | RX_EN_INT;
                dma_wmb();

                /* Move the used descriptor pointer to the next descriptor */
                pep->rx_used_desc_q = (used_rx_desc + 1) % pep->rx_ring_size;

                /* Any Rx return cancels the Rx resource error status */
                pep->rx_resource_err = 0;

                skb_reserve(skb, ETH_HW_IP_ALIGN);
        }

        /*
         * If RX ring is empty of SKB, set a timer to try allocating
         * again at a later time.
         */
        if (pep->rx_desc_count == 0) {
                pep->timeout.expires = jiffies + (HZ / 10);
                add_timer(&pep->timeout);
        }
}

static inline void rxq_refill_timer_wrapper(struct timer_list *t)
{
        struct pxa168_eth_private *pep = from_timer(pep, t, timeout);
        napi_schedule(&pep->napi);
}

static inline u8 flip_8_bits(u8 x)
{
        return (((x) & 0x01) << 3) | (((x) & 0x02) << 1)
            | (((x) & 0x04) >> 1) | (((x) & 0x08) >> 3)
            | (((x) & 0x10) << 3) | (((x) & 0x20) << 1)
            | (((x) & 0x40) >> 1) | (((x) & 0x80) >> 3);
}

static void nibble_swap_every_byte(unsigned char *mac_addr)
{
        int i;
        for (i = 0; i < ETH_ALEN; i++) {
                mac_addr[i] = ((mac_addr[i] & 0x0f) << 4) |
                                ((mac_addr[i] & 0xf0) >> 4);
        }
}

static void inverse_every_nibble(unsigned char *mac_addr)
{
        int i;
        for (i = 0; i < ETH_ALEN; i++)
                mac_addr[i] = flip_8_bits(mac_addr[i]);
}

/*
 * ----------------------------------------------------------------------------
 * This function will calculate the hash function of the address.
 * Inputs
 * mac_addr_orig    - MAC address.
 * Outputs
 * return the calculated entry.
 */
static u32 hash_function(unsigned char *mac_addr_orig)
{
        u32 hash_result;
        u32 addr0;
        u32 addr1;
        u32 addr2;
        u32 addr3;
        unsigned char mac_addr[ETH_ALEN];

        /* Make a copy of MAC address since we are going to performe bit
         * operations on it
         */
        memcpy(mac_addr, mac_addr_orig, ETH_ALEN);

        nibble_swap_every_byte(mac_addr);
        inverse_every_nibble(mac_addr);

        addr0 = (mac_addr[5] >> 2) & 0x3f;
        addr1 = (mac_addr[5] & 0x03) | (((mac_addr[4] & 0x7f)) << 2);
        addr2 = ((mac_addr[4] & 0x80) >> 7) | mac_addr[3] << 1;
        addr3 = (mac_addr[2] & 0xff) | ((mac_addr[1] & 1) << 8);

        hash_result = (addr0 << 9) | (addr1 ^ addr2 ^ addr3);
        hash_result = hash_result & 0x07ff;
        return hash_result;
}

/*
 * ----------------------------------------------------------------------------
 * This function will add/del an entry to the address table.
 * Inputs
 * pep - ETHERNET .
 * mac_addr - MAC address.
 * skip - if 1, skip this address.Used in case of deleting an entry which is a
 *        part of chain in the hash table.We can't just delete the entry since
 *        that will break the chain.We need to defragment the tables time to
 *        time.
 * rd   - 0 Discard packet upon match.
 *      - 1 Receive packet upon match.
 * Outputs
 * address table entry is added/deleted.
 * 0 if success.
 * -ENOSPC if table full
 */
static int add_del_hash_entry(struct pxa168_eth_private *pep,
                              unsigned char *mac_addr,
                              u32 rd, u32 skip, int del)
{
        struct addr_table_entry *entry, *start;
        u32 new_high;
        u32 new_low;
        u32 i;

        new_low = (((mac_addr[1] >> 4) & 0xf) << 15)
            | (((mac_addr[1] >> 0) & 0xf) << 11)
            | (((mac_addr[0] >> 4) & 0xf) << 7)
            | (((mac_addr[0] >> 0) & 0xf) << 3)
            | (((mac_addr[3] >> 4) & 0x1) << 31)
            | (((mac_addr[3] >> 0) & 0xf) << 27)
            | (((mac_addr[2] >> 4) & 0xf) << 23)
            | (((mac_addr[2] >> 0) & 0xf) << 19)
            | (skip << SKIP) | (rd << HASH_ENTRY_RECEIVE_DISCARD_BIT)
            | HASH_ENTRY_VALID;

        new_high = (((mac_addr[5] >> 4) & 0xf) << 15)
            | (((mac_addr[5] >> 0) & 0xf) << 11)
            | (((mac_addr[4] >> 4) & 0xf) << 7)
            | (((mac_addr[4] >> 0) & 0xf) << 3)
            | (((mac_addr[3] >> 5) & 0x7) << 0);

        /*
         * Pick the appropriate table, start scanning for free/reusable
         * entries at the index obtained by hashing the specified MAC address
         */
        start = pep->htpr;
        entry = start + hash_function(mac_addr);
        for (i = 0; i < HOP_NUMBER; i++) {
                if (!(le32_to_cpu(entry->lo) & HASH_ENTRY_VALID)) {
                        break;
                } else {
                        /* if same address put in same position */
                        if (((le32_to_cpu(entry->lo) & 0xfffffff8) ==
                                (new_low & 0xfffffff8)) &&
                                (le32_to_cpu(entry->hi) == new_high)) {
                                break;
                        }
                }
                if (entry == start + 0x7ff)
                        entry = start;
                else
                        entry++;
        }

        if (((le32_to_cpu(entry->lo) & 0xfffffff8) != (new_low & 0xfffffff8)) &&
            (le32_to_cpu(entry->hi) != new_high) && del)
                return 0;

        if (i == HOP_NUMBER) {
                if (!del) {
                        netdev_info(pep->dev,
                                    "%s: table section is full, need to "
                                    "move to 16kB implementation?\n",
                                    __FILE__);
                        return -ENOSPC;
                } else
                        return 0;
        }

        /*
         * Update the selected entry
         */
        if (del) {
                entry->hi = 0;
                entry->lo = 0;
        } else {
                entry->hi = cpu_to_le32(new_high);
                entry->lo = cpu_to_le32(new_low);
        }

        return 0;
}

/*
 * ----------------------------------------------------------------------------
 *  Create an addressTable entry from MAC address info
 *  found in the specifed net_device struct
 *
 *  Input : pointer to ethernet interface network device structure
 *  Output : N/A
 */
static void update_hash_table_mac_address(struct pxa168_eth_private *pep,
                                          unsigned char *oaddr,
                                          unsigned char *addr)
{
        /* Delete old entry */
        if (oaddr)
                add_del_hash_entry(pep, oaddr, 1, 0, HASH_DELETE);
        /* Add new entry */
        add_del_hash_entry(pep, addr, 1, 0, HASH_ADD);
}

static int init_hash_table(struct pxa168_eth_private *pep)
{
        /*
         * Hardware expects CPU to build a hash table based on a predefined
         * hash function and populate it based on hardware address. The
         * location of the hash table is identified by 32-bit pointer stored
         * in HTPR internal register. Two possible sizes exists for the hash
         * table 8kB (256kB of DRAM required (4 x 64 kB banks)) and 1/2kB
         * (16kB of DRAM required (4 x 4 kB banks)).We currently only support
         * 1/2kB.
         */
        /* TODO: Add support for 8kB hash table and alternative hash
         * function.Driver can dynamically switch to them if the 1/2kB hash
         * table is full.
         */
        if (!pep->htpr) {
                pep->htpr = dma_alloc_coherent(pep->dev->dev.parent,
                                               HASH_ADDR_TABLE_SIZE,
                                               &pep->htpr_dma, GFP_KERNEL);
                if (!pep->htpr)
                        return -ENOMEM;
        } else {
                memset(pep->htpr, 0, HASH_ADDR_TABLE_SIZE);
        }
        wrl(pep, HTPR, pep->htpr_dma);
        return 0;
}

static void pxa168_eth_set_rx_mode(struct net_device *dev)
{
        struct pxa168_eth_private *pep = netdev_priv(dev);
        struct netdev_hw_addr *ha;
        u32 val;

        val = rdl(pep, PORT_CONFIG);
        if (dev->flags & IFF_PROMISC)
                val |= PCR_PM;
        else
                val &= ~PCR_PM;
        wrl(pep, PORT_CONFIG, val);

        /*
         * Remove the old list of MAC address and add dev->addr
         * and multicast address.
         */
        memset(pep->htpr, 0, HASH_ADDR_TABLE_SIZE);
        update_hash_table_mac_address(pep, NULL, dev->dev_addr);

        netdev_for_each_mc_addr(ha, dev)
                update_hash_table_mac_address(pep, NULL, ha->addr);
}

static void pxa168_eth_get_mac_address(struct net_device *dev,
                                       unsigned char *addr)
{
        struct pxa168_eth_private *pep = netdev_priv(dev);
        unsigned int mac_h = rdl(pep, MAC_ADDR_HIGH);
        unsigned int mac_l = rdl(pep, MAC_ADDR_LOW);

        addr[0] = (mac_h >> 24) & 0xff;
        addr[1] = (mac_h >> 16) & 0xff;
        addr[2] = (mac_h >> 8) & 0xff;
        addr[3] = mac_h & 0xff;
        addr[4] = (mac_l >> 8) & 0xff;
        addr[5] = mac_l & 0xff;
}

static int pxa168_eth_set_mac_address(struct net_device *dev, void *addr)
{
        struct sockaddr *sa = addr;
        struct pxa168_eth_private *pep = netdev_priv(dev);
        unsigned char oldMac[ETH_ALEN];
        u32 mac_h, mac_l;

        if (!is_valid_ether_addr(sa->sa_data))
                return -EADDRNOTAVAIL;
        memcpy(oldMac, dev->dev_addr, ETH_ALEN);
        memcpy(dev->dev_addr, sa->sa_data, ETH_ALEN);

        mac_h = dev->dev_addr[0] << 24;
        mac_h |= dev->dev_addr[1] << 16;
        mac_h |= dev->dev_addr[2] << 8;
        mac_h |= dev->dev_addr[3];
        mac_l = dev->dev_addr[4] << 8;
        mac_l |= dev->dev_addr[5];
        wrl(pep, MAC_ADDR_HIGH, mac_h);
        wrl(pep, MAC_ADDR_LOW, mac_l);

        netif_addr_lock_bh(dev);
        update_hash_table_mac_address(pep, oldMac, dev->dev_addr);
        netif_addr_unlock_bh(dev);
        return 0;
}

static void eth_port_start(struct net_device *dev)
{
        unsigned int val = 0;
        struct pxa168_eth_private *pep = netdev_priv(dev);
        int tx_curr_desc, rx_curr_desc;

        phy_start(dev->phydev);

        /* Assignment of Tx CTRP of given queue */
        tx_curr_desc = pep->tx_curr_desc_q;
        wrl(pep, ETH_C_TX_DESC_1,
            (u32) (pep->tx_desc_dma + tx_curr_desc * sizeof(struct tx_desc)));

        /* Assignment of Rx CRDP of given queue */
        rx_curr_desc = pep->rx_curr_desc_q;
        wrl(pep, ETH_C_RX_DESC_0,
            (u32) (pep->rx_desc_dma + rx_curr_desc * sizeof(struct rx_desc)));

        wrl(pep, ETH_F_RX_DESC_0,
            (u32) (pep->rx_desc_dma + rx_curr_desc * sizeof(struct rx_desc)));

        /* Clear all interrupts */
        wrl(pep, INT_CAUSE, 0);

        /* Enable all interrupts for receive, transmit and error. */
        wrl(pep, INT_MASK, ALL_INTS);

        val = rdl(pep, PORT_CONFIG);
        val |= PCR_EN;
        wrl(pep, PORT_CONFIG, val);

        /* Start RX DMA engine */
        val = rdl(pep, SDMA_CMD);
        val |= SDMA_CMD_ERD;
        wrl(pep, SDMA_CMD, val);
}

static void eth_port_reset(struct net_device *dev)
{
        struct pxa168_eth_private *pep = netdev_priv(dev);
        unsigned int val = 0;

        /* Stop all interrupts for receive, transmit and error. */
        wrl(pep, INT_MASK, 0);

        /* Clear all interrupts */
        wrl(pep, INT_CAUSE, 0);

        /* Stop RX DMA */
        val = rdl(pep, SDMA_CMD);
        val &= ~SDMA_CMD_ERD;   /* abort dma command */

        /* Abort any transmit and receive operations and put DMA
         * in idle state.
         */
        abort_dma(pep);

        /* Disable port */
        val = rdl(pep, PORT_CONFIG);
        val &= ~PCR_EN;
        wrl(pep, PORT_CONFIG, val);

        phy_stop(dev->phydev);
}

/*
 * txq_reclaim - Free the tx desc data for completed descriptors
 * If force is non-zero, frees uncompleted descriptors as well
 */
static int txq_reclaim(struct net_device *dev, int force)
{
        struct pxa168_eth_private *pep = netdev_priv(dev);
        struct tx_desc *desc;
        u32 cmd_sts;
        struct sk_buff *skb;
        int tx_index;
        dma_addr_t addr;
        int count;
        int released = 0;

        netif_tx_lock(dev);

        pep->work_todo &= ~WORK_TX_DONE;
        while (pep->tx_desc_count > 0) {
                tx_index = pep->tx_used_desc_q;
                desc = &pep->p_tx_desc_area[tx_index];
                cmd_sts = desc->cmd_sts;
                if (!force && (cmd_sts & BUF_OWNED_BY_DMA)) {
                        if (released > 0) {
                                goto txq_reclaim_end;
                        } else {
                                released = -1;
                                goto txq_reclaim_end;
                        }
                }
                pep->tx_used_desc_q = (tx_index + 1) % pep->tx_ring_size;
                pep->tx_desc_count--;
                addr = desc->buf_ptr;
                count = desc->byte_cnt;
                skb = pep->tx_skb[tx_index];
                if (skb)
                        pep->tx_skb[tx_index] = NULL;

                if (cmd_sts & TX_ERROR) {
                        if (net_ratelimit())
                                netdev_err(dev, "Error in TX\n");
                        dev->stats.tx_errors++;
                }
                dma_unmap_single(&pep->pdev->dev, addr, count, DMA_TO_DEVICE);
                if (skb)
                        dev_kfree_skb_irq(skb);
                released++;
        }
txq_reclaim_end:
        netif_tx_unlock(dev);
        return released;
}

static void pxa168_eth_tx_timeout(struct net_device *dev, unsigned int txqueue)
{
        struct pxa168_eth_private *pep = netdev_priv(dev);

        netdev_info(dev, "TX timeout  desc_count %d\n", pep->tx_desc_count);

        schedule_work(&pep->tx_timeout_task);
}

static void pxa168_eth_tx_timeout_task(struct work_struct *work)
{
        struct pxa168_eth_private *pep = container_of(work,
                                                 struct pxa168_eth_private,
                                                 tx_timeout_task);
        struct net_device *dev = pep->dev;
        pxa168_eth_stop(dev);
        pxa168_eth_open(dev);
}

static int rxq_process(struct net_device *dev, int budget)
{
        struct pxa168_eth_private *pep = netdev_priv(dev);
        struct net_device_stats *stats = &dev->stats;
        unsigned int received_packets = 0;
        struct sk_buff *skb;

        while (budget-- > 0) {
                int rx_next_curr_desc, rx_curr_desc, rx_used_desc;
                struct rx_desc *rx_desc;
                unsigned int cmd_sts;

                /* Do not process Rx ring in case of Rx ring resource error */
                if (pep->rx_resource_err)
                        break;
                rx_curr_desc = pep->rx_curr_desc_q;
                rx_used_desc = pep->rx_used_desc_q;
                rx_desc = &pep->p_rx_desc_area[rx_curr_desc];
                cmd_sts = rx_desc->cmd_sts;
                dma_rmb();
                if (cmd_sts & (BUF_OWNED_BY_DMA))
                        break;
                skb = pep->rx_skb[rx_curr_desc];
                pep->rx_skb[rx_curr_desc] = NULL;

                rx_next_curr_desc = (rx_curr_desc + 1) % pep->rx_ring_size;
                pep->rx_curr_desc_q = rx_next_curr_desc;

                /* Rx descriptors exhausted. */
                /* Set the Rx ring resource error flag */
                if (rx_next_curr_desc == rx_used_desc)
                        pep->rx_resource_err = 1;
                pep->rx_desc_count--;
                dma_unmap_single(&pep->pdev->dev, rx_desc->buf_ptr,
                                 rx_desc->buf_size,
                                 DMA_FROM_DEVICE);
                received_packets++;
                /*
                 * Update statistics.
                 * Note byte count includes 4 byte CRC count
                 */
                stats->rx_packets++;
                stats->rx_bytes += rx_desc->byte_cnt;
                /*
                 * In case received a packet without first / last bits on OR
                 * the error summary bit is on, the packets needs to be droped.
                 */
                if (((cmd_sts & (RX_FIRST_DESC | RX_LAST_DESC)) !=
                     (RX_FIRST_DESC | RX_LAST_DESC))
                    || (cmd_sts & RX_ERROR)) {

                        stats->rx_dropped++;
                        if ((cmd_sts & (RX_FIRST_DESC | RX_LAST_DESC)) !=
                            (RX_FIRST_DESC | RX_LAST_DESC)) {
                                if (net_ratelimit())
                                        netdev_err(dev,
                                                   "Rx pkt on multiple desc\n");
                        }
                        if (cmd_sts & RX_ERROR)
                                stats->rx_errors++;
                        dev_kfree_skb_irq(skb);
                } else {
                        /*
                         * The -4 is for the CRC in the trailer of the
                         * received packet
                         */
                        skb_put(skb, rx_desc->byte_cnt - 4);
                        skb->protocol = eth_type_trans(skb, dev);
                        netif_receive_skb(skb);
                }
        }
        /* Fill RX ring with skb's */
        rxq_refill(dev);
        return received_packets;
}

static int pxa168_eth_collect_events(struct pxa168_eth_private *pep,
                                     struct net_device *dev)
{
        u32 icr;
        int ret = 0;

        icr = rdl(pep, INT_CAUSE);
        if (icr == 0)
                return IRQ_NONE;

        wrl(pep, INT_CAUSE, ~icr);
        if (icr & (ICR_TXBUF_H | ICR_TXBUF_L)) {
                pep->work_todo |= WORK_TX_DONE;
                ret = 1;
        }
        if (icr & ICR_RXBUF)
                ret = 1;
        return ret;
}

static irqreturn_t pxa168_eth_int_handler(int irq, void *dev_id)
{
        struct net_device *dev = (struct net_device *)dev_id;
        struct pxa168_eth_private *pep = netdev_priv(dev);

        if (unlikely(!pxa168_eth_collect_events(pep, dev)))
                return IRQ_NONE;
        /* Disable interrupts */
        wrl(pep, INT_MASK, 0);
        napi_schedule(&pep->napi);
        return IRQ_HANDLED;
}

static void pxa168_eth_recalc_skb_size(struct pxa168_eth_private *pep)
{
        int skb_size;

        /*
         * Reserve 2+14 bytes for an ethernet header (the hardware
         * automatically prepends 2 bytes of dummy data to each
         * received packet), 16 bytes for up to four VLAN tags, and
         * 4 bytes for the trailing FCS -- 36 bytes total.
         */
        skb_size = pep->dev->mtu + 36;

        /*
         * Make sure that the skb size is a multiple of 8 bytes, as
         * the lower three bits of the receive descriptor's buffer
         * size field are ignored by the hardware.
         */
        pep->skb_size = (skb_size + 7) & ~7;

        /*
         * If NET_SKB_PAD is smaller than a cache line,
         * netdev_alloc_skb() will cause skb->data to be misaligned
         * to a cache line boundary.  If this is the case, include
         * some extra space to allow re-aligning the data area.
         */
        pep->skb_size += SKB_DMA_REALIGN;

}

static int set_port_config_ext(struct pxa168_eth_private *pep)
{
        int skb_size;

        pxa168_eth_recalc_skb_size(pep);
        if  (pep->skb_size <= 1518)
                skb_size = PCXR_MFL_1518;
        else if (pep->skb_size <= 1536)
                skb_size = PCXR_MFL_1536;
        else if (pep->skb_size <= 2048)
                skb_size = PCXR_MFL_2048;
        else
                skb_size = PCXR_MFL_64K;

        /* Extended Port Configuration */
        wrl(pep, PORT_CONFIG_EXT,
            PCXR_AN_SPEED_DIS |          /* Disable HW AN */
            PCXR_AN_DUPLEX_DIS |
            PCXR_AN_FLOWCTL_DIS |
            PCXR_2BSM |                  /* Two byte prefix aligns IP hdr */
            PCXR_DSCP_EN |               /* Enable DSCP in IP */
            skb_size | PCXR_FLP |        /* do not force link pass */
            PCXR_TX_HIGH_PRI);           /* Transmit - high priority queue */

        return 0;
}

static void pxa168_eth_adjust_link(struct net_device *dev)
{
        struct pxa168_eth_private *pep = netdev_priv(dev);
        struct phy_device *phy = dev->phydev;
        u32 cfg, cfg_o = rdl(pep, PORT_CONFIG);
        u32 cfgext, cfgext_o = rdl(pep, PORT_CONFIG_EXT);

        cfg = cfg_o & ~PCR_DUPLEX_FULL;
        cfgext = cfgext_o & ~(PCXR_SPEED_100 | PCXR_FLOWCTL_DIS | PCXR_RMII_EN);

        if (phy->interface == PHY_INTERFACE_MODE_RMII)
                cfgext |= PCXR_RMII_EN;
        if (phy->speed == SPEED_100)
                cfgext |= PCXR_SPEED_100;
        if (phy->duplex)
                cfg |= PCR_DUPLEX_FULL;
        if (!phy->pause)
                cfgext |= PCXR_FLOWCTL_DIS;

        /* Bail out if there has nothing changed */
        if (cfg == cfg_o && cfgext == cfgext_o)
                return;

        wrl(pep, PORT_CONFIG, cfg);
        wrl(pep, PORT_CONFIG_EXT, cfgext);

        phy_print_status(phy);
}

static int pxa168_init_phy(struct net_device *dev)
{
        struct pxa168_eth_private *pep = netdev_priv(dev);
        struct ethtool_link_ksettings cmd;
        struct phy_device *phy = NULL;
        int err;

        if (dev->phydev)
                return 0;

        phy = mdiobus_scan(pep->smi_bus, pep->phy_addr);
        if (IS_ERR(phy))
                return PTR_ERR(phy);

        err = phy_connect_direct(dev, phy, pxa168_eth_adjust_link,
                                 pep->phy_intf);
        if (err)
                return err;

        cmd.base.phy_address = pep->phy_addr;
        cmd.base.speed = pep->phy_speed;
        cmd.base.duplex = pep->phy_duplex;
        bitmap_copy(cmd.link_modes.advertising, PHY_BASIC_FEATURES,
                    __ETHTOOL_LINK_MODE_MASK_NBITS);
        cmd.base.autoneg = AUTONEG_ENABLE;

        if (cmd.base.speed != 0)
                cmd.base.autoneg = AUTONEG_DISABLE;

        return phy_ethtool_set_link_ksettings(dev, &cmd);
}

static int pxa168_init_hw(struct pxa168_eth_private *pep)
{
        int err = 0;

        /* Disable interrupts */
        wrl(pep, INT_MASK, 0);
        wrl(pep, INT_CAUSE, 0);
        /* Write to ICR to clear interrupts. */
        wrl(pep, INT_W_CLEAR, 0);
        /* Abort any transmit and receive operations and put DMA
         * in idle state.

         */
        abort_dma(pep);
        /* Initialize address hash table */
        err = init_hash_table(pep);
        if (err)
                return err;
        /* SDMA configuration */
        wrl(pep, SDMA_CONFIG, SDCR_BSZ8 |       /* Burst size = 32 bytes */
            SDCR_RIFB |                         /* Rx interrupt on frame */
            SDCR_BLMT |                         /* Little endian transmit */
            SDCR_BLMR |                         /* Little endian receive */
            SDCR_RC_MAX_RETRANS);               /* Max retransmit count */
        /* Port Configuration */
        wrl(pep, PORT_CONFIG, PCR_HS);          /* Hash size is 1/2kb */
        set_port_config_ext(pep);

        return err;
}

static int rxq_init(struct net_device *dev)
{
        struct pxa168_eth_private *pep = netdev_priv(dev);
        struct rx_desc *p_rx_desc;
        int size = 0, i = 0;
        int rx_desc_num = pep->rx_ring_size;

        /* Allocate RX skb rings */
        pep->rx_skb = kcalloc(rx_desc_num, sizeof(*pep->rx_skb), GFP_KERNEL);
        if (!pep->rx_skb)
                return -ENOMEM;

        /* Allocate RX ring */
        pep->rx_desc_count = 0;
        size = pep->rx_ring_size * sizeof(struct rx_desc);
        pep->rx_desc_area_size = size;
        pep->p_rx_desc_area = dma_alloc_coherent(pep->dev->dev.parent, size,
                                                 &pep->rx_desc_dma,
                                                 GFP_KERNEL);
        if (!pep->p_rx_desc_area)
                goto out;

        /* initialize the next_desc_ptr links in the Rx descriptors ring */
        p_rx_desc = pep->p_rx_desc_area;
        for (i = 0; i < rx_desc_num; i++) {
                p_rx_desc[i].next_desc_ptr = pep->rx_desc_dma +
                    ((i + 1) % rx_desc_num) * sizeof(struct rx_desc);
        }
        /* Save Rx desc pointer to driver struct. */
        pep->rx_curr_desc_q = 0;
        pep->rx_used_desc_q = 0;
        pep->rx_desc_area_size = rx_desc_num * sizeof(struct rx_desc);
        return 0;
out:
        kfree(pep->rx_skb);
        return -ENOMEM;
}

static void rxq_deinit(struct net_device *dev)
{
        struct pxa168_eth_private *pep = netdev_priv(dev);
        int curr;

        /* Free preallocated skb's on RX rings */
        for (curr = 0; pep->rx_desc_count && curr < pep->rx_ring_size; curr++) {
                if (pep->rx_skb[curr]) {
                        dev_kfree_skb(pep->rx_skb[curr]);
                        pep->rx_desc_count--;
                }
        }
        if (pep->rx_desc_count)
                netdev_err(dev, "Error in freeing Rx Ring. %d skb's still\n",
                           pep->rx_desc_count);
        /* Free RX ring */
        if (pep->p_rx_desc_area)
                dma_free_coherent(pep->dev->dev.parent, pep->rx_desc_area_size,
                                  pep->p_rx_desc_area, pep->rx_desc_dma);
        kfree(pep->rx_skb);
}

static int txq_init(struct net_device *dev)
{
        struct pxa168_eth_private *pep = netdev_priv(dev);
        struct tx_desc *p_tx_desc;
        int size = 0, i = 0;
        int tx_desc_num = pep->tx_ring_size;

        pep->tx_skb = kcalloc(tx_desc_num, sizeof(*pep->tx_skb), GFP_KERNEL);
        if (!pep->tx_skb)
                return -ENOMEM;

        /* Allocate TX ring */
        pep->tx_desc_count = 0;
        size = pep->tx_ring_size * sizeof(struct tx_desc);
        pep->tx_desc_area_size = size;
        pep->p_tx_desc_area = dma_alloc_coherent(pep->dev->dev.parent, size,
                                                 &pep->tx_desc_dma,
                                                 GFP_KERNEL);
        if (!pep->p_tx_desc_area)
                goto out;
        /* Initialize the next_desc_ptr links in the Tx descriptors ring */
        p_tx_desc = pep->p_tx_desc_area;
        for (i = 0; i < tx_desc_num; i++) {
                p_tx_desc[i].next_desc_ptr = pep->tx_desc_dma +
                    ((i + 1) % tx_desc_num) * sizeof(struct tx_desc);
        }
        pep->tx_curr_desc_q = 0;
        pep->tx_used_desc_q = 0;
        pep->tx_desc_area_size = tx_desc_num * sizeof(struct tx_desc);
        return 0;
out:
        kfree(pep->tx_skb);
        return -ENOMEM;
}

static void txq_deinit(struct net_device *dev)
{
        struct pxa168_eth_private *pep = netdev_priv(dev);

        /* Free outstanding skb's on TX ring */
        txq_reclaim(dev, 1);
        BUG_ON(pep->tx_used_desc_q != pep->tx_curr_desc_q);
        /* Free TX ring */
        if (pep->p_tx_desc_area)
                dma_free_coherent(pep->dev->dev.parent, pep->tx_desc_area_size,
                                  pep->p_tx_desc_area, pep->tx_desc_dma);
        kfree(pep->tx_skb);
}

static int pxa168_eth_open(struct net_device *dev)
{
        struct pxa168_eth_private *pep = netdev_priv(dev);
        int err;

        err = pxa168_init_phy(dev);
        if (err)
                return err;

        err = request_irq(dev->irq, pxa168_eth_int_handler, 0, dev->name, dev);
        if (err) {
                dev_err(&dev->dev, "can't assign irq\n");
                return -EAGAIN;
        }
        pep->rx_resource_err = 0;
        err = rxq_init(dev);
        if (err != 0)
                goto out_free_irq;
        err = txq_init(dev);
        if (err != 0)
                goto out_free_rx_skb;
        pep->rx_used_desc_q = 0;
        pep->rx_curr_desc_q = 0;

        /* Fill RX ring with skb's */
        rxq_refill(dev);
        pep->rx_used_desc_q = 0;
        pep->rx_curr_desc_q = 0;
        netif_carrier_off(dev);
        napi_enable(&pep->napi);
        eth_port_start(dev);
        return 0;
out_free_rx_skb:
        rxq_deinit(dev);
out_free_irq:
        free_irq(dev->irq, dev);
        return err;
}

static int pxa168_eth_stop(struct net_device *dev)
{
        struct pxa168_eth_private *pep = netdev_priv(dev);
        eth_port_reset(dev);

        /* Disable interrupts */
        wrl(pep, INT_MASK, 0);
        wrl(pep, INT_CAUSE, 0);
        /* Write to ICR to clear interrupts. */
        wrl(pep, INT_W_CLEAR, 0);
        napi_disable(&pep->napi);
        del_timer_sync(&pep->timeout);
        netif_carrier_off(dev);
        free_irq(dev->irq, dev);
        rxq_deinit(dev);
        txq_deinit(dev);

        return 0;
}

static int pxa168_eth_change_mtu(struct net_device *dev, int mtu)
{
        struct pxa168_eth_private *pep = netdev_priv(dev);

        dev->mtu = mtu;
        set_port_config_ext(pep);

        if (!netif_running(dev))
                return 0;

        /*
         * Stop and then re-open the interface. This will allocate RX
         * skbs of the new MTU.
         * There is a possible danger that the open will not succeed,
         * due to memory being full.
         */
        pxa168_eth_stop(dev);
        if (pxa168_eth_open(dev)) {
                dev_err(&dev->dev,
                        "fatal error on re-opening device after MTU change\n");
        }

        return 0;
}

static int eth_alloc_tx_desc_index(struct pxa168_eth_private *pep)
{
        int tx_desc_curr;

        tx_desc_curr = pep->tx_curr_desc_q;
        pep->tx_curr_desc_q = (tx_desc_curr + 1) % pep->tx_ring_size;
        BUG_ON(pep->tx_curr_desc_q == pep->tx_used_desc_q);
        pep->tx_desc_count++;

        return tx_desc_curr;
}

static int pxa168_rx_poll(struct napi_struct *napi, int budget)
{
        struct pxa168_eth_private *pep =
            container_of(napi, struct pxa168_eth_private, napi);
        struct net_device *dev = pep->dev;
        int work_done = 0;

        /*
         * We call txq_reclaim every time since in NAPI interupts are disabled
         * and due to this we miss the TX_DONE interrupt,which is not updated in
         * interrupt status register.
         */
        txq_reclaim(dev, 0);
        if (netif_queue_stopped(dev)
            && pep->tx_ring_size - pep->tx_desc_count > 1) {
                netif_wake_queue(dev);
        }
        work_done = rxq_process(dev, budget);
        if (work_done < budget) {
                napi_complete_done(napi, work_done);
                wrl(pep, INT_MASK, ALL_INTS);
        }

        return work_done;
}

static netdev_tx_t
pxa168_eth_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
        struct pxa168_eth_private *pep = netdev_priv(dev);
        struct net_device_stats *stats = &dev->stats;
        struct tx_desc *desc;
        int tx_index;
        int length;

        tx_index = eth_alloc_tx_desc_index(pep);
        desc = &pep->p_tx_desc_area[tx_index];
        length = skb->len;
        pep->tx_skb[tx_index] = skb;
        desc->byte_cnt = length;
        desc->buf_ptr = dma_map_single(&pep->pdev->dev, skb->data, length,
                                        DMA_TO_DEVICE);

        skb_tx_timestamp(skb);

        dma_wmb();
        desc->cmd_sts = BUF_OWNED_BY_DMA | TX_GEN_CRC | TX_FIRST_DESC |
                        TX_ZERO_PADDING | TX_LAST_DESC | TX_EN_INT;
        wmb();
        wrl(pep, SDMA_CMD, SDMA_CMD_TXDH | SDMA_CMD_ERD);

        stats->tx_bytes += length;
        stats->tx_packets++;
        netif_trans_update(dev);
        if (pep->tx_ring_size - pep->tx_desc_count <= 1) {
                /* We handled the current skb, but now we are out of space.*/
                netif_stop_queue(dev);
        }

        return NETDEV_TX_OK;
}

static int smi_wait_ready(struct pxa168_eth_private *pep)
{
        int i = 0;

        /* wait for the SMI register to become available */
        for (i = 0; rdl(pep, SMI) & SMI_BUSY; i++) {
                if (i == PHY_WAIT_ITERATIONS)
                        return -ETIMEDOUT;
                msleep(10);
        }

        return 0;
}

static int pxa168_smi_read(struct mii_bus *bus, int phy_addr, int regnum)
{
        struct pxa168_eth_private *pep = bus->priv;
        int i = 0;
        int val;

        if (smi_wait_ready(pep)) {
                netdev_warn(pep->dev, "pxa168_eth: SMI bus busy timeout\n");
                return -ETIMEDOUT;
        }
        wrl(pep, SMI, (phy_addr << 16) | (regnum << 21) | SMI_OP_R);
        /* now wait for the data to be valid */
        for (i = 0; !((val = rdl(pep, SMI)) & SMI_R_VALID); i++) {
                if (i == PHY_WAIT_ITERATIONS) {
                        netdev_warn(pep->dev,
                                    "pxa168_eth: SMI bus read not valid\n");
                        return -ENODEV;
                }
                msleep(10);
        }

        return val & 0xffff;
}

static int pxa168_smi_write(struct mii_bus *bus, int phy_addr, int regnum,
                            u16 value)
{
        struct pxa168_eth_private *pep = bus->priv;

        if (smi_wait_ready(pep)) {
                netdev_warn(pep->dev, "pxa168_eth: SMI bus busy timeout\n");
                return -ETIMEDOUT;
        }

        wrl(pep, SMI, (phy_addr << 16) | (regnum << 21) |
            SMI_OP_W | (value & 0xffff));

        if (smi_wait_ready(pep)) {
                netdev_err(pep->dev, "pxa168_eth: SMI bus busy timeout\n");
                return -ETIMEDOUT;
        }

        return 0;
}

#ifdef CONFIG_NET_POLL_CONTROLLER
static void pxa168_eth_netpoll(struct net_device *dev)
{
        disable_irq(dev->irq);
        pxa168_eth_int_handler(dev->irq, dev);
        enable_irq(dev->irq);
}
#endif

static void pxa168_get_drvinfo(struct net_device *dev,
                               struct ethtool_drvinfo *info)
{
        strlcpy(info->driver, DRIVER_NAME, sizeof(info->driver));
        strlcpy(info->version, DRIVER_VERSION, sizeof(info->version));
        strlcpy(info->fw_version, "N/A", sizeof(info->fw_version));
        strlcpy(info->bus_info, "N/A", sizeof(info->bus_info));
}

static const struct ethtool_ops pxa168_ethtool_ops = {
        .get_drvinfo    = pxa168_get_drvinfo,
        .nway_reset     = phy_ethtool_nway_reset,
        .get_link       = ethtool_op_get_link,
        .get_ts_info    = ethtool_op_get_ts_info,
        .get_link_ksettings = phy_ethtool_get_link_ksettings,
        .set_link_ksettings = phy_ethtool_set_link_ksettings,
};

static const struct net_device_ops pxa168_eth_netdev_ops = {
        .ndo_open               = pxa168_eth_open,
        .ndo_stop               = pxa168_eth_stop,
        .ndo_start_xmit         = pxa168_eth_start_xmit,
        .ndo_set_rx_mode        = pxa168_eth_set_rx_mode,
        .ndo_set_mac_address    = pxa168_eth_set_mac_address,
        .ndo_validate_addr      = eth_validate_addr,
        .ndo_do_ioctl           = phy_do_ioctl,
        .ndo_change_mtu         = pxa168_eth_change_mtu,
        .ndo_tx_timeout         = pxa168_eth_tx_timeout,
#ifdef CONFIG_NET_POLL_CONTROLLER
        .ndo_poll_controller    = pxa168_eth_netpoll,
#endif
};

static int pxa168_eth_probe(struct platform_device *pdev)
{
        struct pxa168_eth_private *pep = NULL;
        struct net_device *dev = NULL;
        struct resource *res;
        struct clk *clk;
        struct device_node *np;
        const unsigned char *mac_addr = NULL;
        int err;

        printk(KERN_NOTICE "PXA168 10/100 Ethernet Driver\n");

        clk = devm_clk_get(&pdev->dev, NULL);
        if (IS_ERR(clk)) {
                dev_err(&pdev->dev, "Fast Ethernet failed to get clock\n");
                return -ENODEV;
        }
        clk_prepare_enable(clk);

        dev = alloc_etherdev(sizeof(struct pxa168_eth_private));
        if (!dev) {
                err = -ENOMEM;
                goto err_clk;
        }

        platform_set_drvdata(pdev, dev);
        pep = netdev_priv(dev);
        pep->dev = dev;
        pep->clk = clk;

        pep->base = devm_platform_ioremap_resource(pdev, 0);
        if (IS_ERR(pep->base)) {
                err = PTR_ERR(pep->base);
                goto err_netdev;
        }

        res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
        BUG_ON(!res);
        dev->irq = res->start;
        dev->netdev_ops = &pxa168_eth_netdev_ops;
        dev->watchdog_timeo = 2 * HZ;
        dev->base_addr = 0;
        dev->ethtool_ops = &pxa168_ethtool_ops;

        /* MTU range: 68 - 9500 */
        dev->min_mtu = ETH_MIN_MTU;
        dev->max_mtu = 9500;

        INIT_WORK(&pep->tx_timeout_task, pxa168_eth_tx_timeout_task);

        if (pdev->dev.of_node)
                mac_addr = of_get_mac_address(pdev->dev.of_node);

        if (!IS_ERR_OR_NULL(mac_addr)) {
                ether_addr_copy(dev->dev_addr, mac_addr);
        } else {
                /* try reading the mac address, if set by the bootloader */
                pxa168_eth_get_mac_address(dev, dev->dev_addr);
                if (!is_valid_ether_addr(dev->dev_addr)) {
                        dev_info(&pdev->dev, "Using random mac address\n");
                        eth_hw_addr_random(dev);
                }
        }

        pep->rx_ring_size = NUM_RX_DESCS;
        pep->tx_ring_size = NUM_TX_DESCS;

        pep->pd = dev_get_platdata(&pdev->dev);
        if (pep->pd) {
                if (pep->pd->rx_queue_size)
                        pep->rx_ring_size = pep->pd->rx_queue_size;

                if (pep->pd->tx_queue_size)
                        pep->tx_ring_size = pep->pd->tx_queue_size;

                pep->port_num = pep->pd->port_number;
                pep->phy_addr = pep->pd->phy_addr;
                pep->phy_speed = pep->pd->speed;
                pep->phy_duplex = pep->pd->duplex;
                pep->phy_intf = pep->pd->intf;

                if (pep->pd->init)
                        pep->pd->init();
        } else if (pdev->dev.of_node) {
                of_property_read_u32(pdev->dev.of_node, "port-id",
                                     &pep->port_num);

                np = of_parse_phandle(pdev->dev.of_node, "phy-handle", 0);
                if (!np) {
                        dev_err(&pdev->dev, "missing phy-handle\n");
                        err = -EINVAL;
                        goto err_netdev;
                }
                of_property_read_u32(np, "reg", &pep->phy_addr);
                of_node_put(np);
                err = of_get_phy_mode(pdev->dev.of_node, &pep->phy_intf);
                if (err && err != -ENODEV)
                        goto err_netdev;
        }

        /* Hardware supports only 3 ports */
        BUG_ON(pep->port_num > 2);
        netif_napi_add(dev, &pep->napi, pxa168_rx_poll, pep->rx_ring_size);

        memset(&pep->timeout, 0, sizeof(struct timer_list));
        timer_setup(&pep->timeout, rxq_refill_timer_wrapper, 0);

        pep->smi_bus = mdiobus_alloc();
        if (!pep->smi_bus) {
                err = -ENOMEM;
                goto err_netdev;
        }
        pep->smi_bus->priv = pep;
        pep->smi_bus->name = "pxa168_eth smi";
        pep->smi_bus->read = pxa168_smi_read;
        pep->smi_bus->write = pxa168_smi_write;
        snprintf(pep->smi_bus->id, MII_BUS_ID_SIZE, "%s-%d",
                pdev->name, pdev->id);
        pep->smi_bus->parent = &pdev->dev;
        pep->smi_bus->phy_mask = 0xffffffff;
        err = mdiobus_register(pep->smi_bus);
        if (err)
                goto err_free_mdio;

        pep->pdev = pdev;
        SET_NETDEV_DEV(dev, &pdev->dev);
        pxa168_init_hw(pep);
        err = register_netdev(dev);
        if (err)
                goto err_mdiobus;
        return 0;

err_mdiobus:
        mdiobus_unregister(pep->smi_bus);
err_free_mdio:
        mdiobus_free(pep->smi_bus);
err_netdev:
        free_netdev(dev);
err_clk:
        clk_disable_unprepare(clk);
        return err;
}

static int pxa168_eth_remove(struct platform_device *pdev)
{
        struct net_device *dev = platform_get_drvdata(pdev);
        struct pxa168_eth_private *pep = netdev_priv(dev);

        if (pep->htpr) {
                dma_free_coherent(pep->dev->dev.parent, HASH_ADDR_TABLE_SIZE,
                                  pep->htpr, pep->htpr_dma);
                pep->htpr = NULL;
        }
        if (dev->phydev)
                phy_disconnect(dev->phydev);

        clk_disable_unprepare(pep->clk);
        mdiobus_unregister(pep->smi_bus);
        mdiobus_free(pep->smi_bus);
        cancel_work_sync(&pep->tx_timeout_task);
        unregister_netdev(dev);
        free_netdev(dev);
        return 0;
}

static void pxa168_eth_shutdown(struct platform_device *pdev)
{
        struct net_device *dev = platform_get_drvdata(pdev);
        eth_port_reset(dev);
}

#ifdef CONFIG_PM
static int pxa168_eth_resume(struct platform_device *pdev)
{
        return -ENOSYS;
}

static int pxa168_eth_suspend(struct platform_device *pdev, pm_message_t state)
{
        return -ENOSYS;
}

#else
#define pxa168_eth_resume NULL
#define pxa168_eth_suspend NULL
#endif

static const struct of_device_id pxa168_eth_of_match[] = {
        { .compatible = "marvell,pxa168-eth" },
        { },
};
MODULE_DEVICE_TABLE(of, pxa168_eth_of_match);

static struct platform_driver pxa168_eth_driver = {
        .probe = pxa168_eth_probe,
        .remove = pxa168_eth_remove,
        .shutdown = pxa168_eth_shutdown,
        .resume = pxa168_eth_resume,
        .suspend = pxa168_eth_suspend,
        .driver = {
                .name           = DRIVER_NAME,
                .of_match_table = of_match_ptr(pxa168_eth_of_match),
        },
};

module_platform_driver(pxa168_eth_driver);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Ethernet driver for Marvell PXA168");
MODULE_ALIAS("platform:pxa168_eth");