/*
 * Keystone NetCP Core driver
 *
 * Copyright (C) 2014 Texas Instruments Incorporated
 * Authors:     Sandeep Nair <sandeep_n@ti.com>
 *              Sandeep Paulraj <s-paulraj@ti.com>
 *              Cyril Chemparathy <cyril@ti.com>
 *              Santosh Shilimkar <santosh.shilimkar@ti.com>
 *              Murali Karicheri <m-karicheri2@ti.com>
 *              Wingman Kwok <w-kwok2@ti.com>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation version 2.
 *
 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
 * kind, whether express or implied; without even the implied warranty
 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */

#include <linux/io.h>
#include <linux/module.h>
#include <linux/of_net.h>
#include <linux/of_address.h>
#include <linux/if_vlan.h>
#include <linux/pm_runtime.h>
#include <linux/platform_device.h>
#include <linux/soc/ti/knav_qmss.h>
#include <linux/soc/ti/knav_dma.h>

#include "netcp.h"

#define NETCP_SOP_OFFSET        (NET_IP_ALIGN + NET_SKB_PAD)
#define NETCP_NAPI_WEIGHT       64
#define NETCP_TX_TIMEOUT        (5 * HZ)
#define NETCP_PACKET_SIZE       (ETH_FRAME_LEN + ETH_FCS_LEN)
#define NETCP_MIN_PACKET_SIZE   ETH_ZLEN
#define NETCP_MAX_MCAST_ADDR    16

#define NETCP_EFUSE_REG_INDEX   0

#define NETCP_MOD_PROBE_SKIPPED 1
#define NETCP_MOD_PROBE_FAILED  2

#define NETCP_DEBUG (NETIF_MSG_HW       | NETIF_MSG_WOL         |       \
                    NETIF_MSG_DRV       | NETIF_MSG_LINK        |       \
                    NETIF_MSG_IFUP      | NETIF_MSG_INTR        |       \
                    NETIF_MSG_PROBE     | NETIF_MSG_TIMER       |       \
                    NETIF_MSG_IFDOWN    | NETIF_MSG_RX_ERR      |       \
                    NETIF_MSG_TX_ERR    | NETIF_MSG_TX_DONE     |       \
                    NETIF_MSG_PKTDATA   | NETIF_MSG_TX_QUEUED   |       \
                    NETIF_MSG_RX_STATUS)

#define NETCP_EFUSE_ADDR_SWAP   2

#define knav_queue_get_id(q)    knav_queue_device_control(q, \
                                KNAV_QUEUE_GET_ID, (unsigned long)NULL)

#define knav_queue_enable_notify(q) knav_queue_device_control(q,        \
                                        KNAV_QUEUE_ENABLE_NOTIFY,       \
                                        (unsigned long)NULL)

#define knav_queue_disable_notify(q) knav_queue_device_control(q,       \
                                        KNAV_QUEUE_DISABLE_NOTIFY,      \
                                        (unsigned long)NULL)

#define knav_queue_get_count(q) knav_queue_device_control(q, \
                                KNAV_QUEUE_GET_COUNT, (unsigned long)NULL)

#define for_each_netcp_module(module)                   \
        list_for_each_entry(module, &netcp_modules, module_list)

#define for_each_netcp_device_module(netcp_device, inst_modpriv) \
        list_for_each_entry(inst_modpriv, \
                &((netcp_device)->modpriv_head), inst_list)

#define for_each_module(netcp, intf_modpriv)                    \
        list_for_each_entry(intf_modpriv, &netcp->module_head, intf_list)

/* Module management structures */
struct netcp_device {
        struct list_head        device_list;
        struct list_head        interface_head;
        struct list_head        modpriv_head;
        struct device           *device;
};

struct netcp_inst_modpriv {
        struct netcp_device     *netcp_device;
        struct netcp_module     *netcp_module;
        struct list_head        inst_list;
        void                    *module_priv;
};

struct netcp_intf_modpriv {
        struct netcp_intf       *netcp_priv;
        struct netcp_module     *netcp_module;
        struct list_head        intf_list;
        void                    *module_priv;
};

struct netcp_tx_cb {
        void    *ts_context;
        void    (*txtstamp)(void *context, struct sk_buff *skb);
};

static LIST_HEAD(netcp_devices);
static LIST_HEAD(netcp_modules);
static DEFINE_MUTEX(netcp_modules_lock);

static int netcp_debug_level = -1;
module_param(netcp_debug_level, int, 0);
MODULE_PARM_DESC(netcp_debug_level, "Netcp debug level (NETIF_MSG bits) (0=none,...,16=all)");

/* Helper functions - Get/Set */
static void get_pkt_info(dma_addr_t *buff, u32 *buff_len, dma_addr_t *ndesc,
                         struct knav_dma_desc *desc)
{
        *buff_len = le32_to_cpu(desc->buff_len);
        *buff = le32_to_cpu(desc->buff);
        *ndesc = le32_to_cpu(desc->next_desc);
}

static void get_desc_info(u32 *desc_info, u32 *pkt_info,
                          struct knav_dma_desc *desc)
{
        *desc_info = le32_to_cpu(desc->desc_info);
        *pkt_info = le32_to_cpu(desc->packet_info);
}

static u32 get_sw_data(int index, struct knav_dma_desc *desc)
{
        /* No Endian conversion needed as this data is untouched by hw */
        return desc->sw_data[index];
}

/* use these macros to get sw data */
#define GET_SW_DATA0(desc) get_sw_data(0, desc)
#define GET_SW_DATA1(desc) get_sw_data(1, desc)
#define GET_SW_DATA2(desc) get_sw_data(2, desc)
#define GET_SW_DATA3(desc) get_sw_data(3, desc)

static void get_org_pkt_info(dma_addr_t *buff, u32 *buff_len,
                             struct knav_dma_desc *desc)
{
        *buff = le32_to_cpu(desc->orig_buff);
        *buff_len = le32_to_cpu(desc->orig_len);
}

static void get_words(dma_addr_t *words, int num_words, __le32 *desc)
{
        int i;

        for (i = 0; i < num_words; i++)
                words[i] = le32_to_cpu(desc[i]);
}

static void set_pkt_info(dma_addr_t buff, u32 buff_len, u32 ndesc,
                         struct knav_dma_desc *desc)
{
        desc->buff_len = cpu_to_le32(buff_len);
        desc->buff = cpu_to_le32(buff);
        desc->next_desc = cpu_to_le32(ndesc);
}

static void set_desc_info(u32 desc_info, u32 pkt_info,
                          struct knav_dma_desc *desc)
{
        desc->desc_info = cpu_to_le32(desc_info);
        desc->packet_info = cpu_to_le32(pkt_info);
}

static void set_sw_data(int index, u32 data, struct knav_dma_desc *desc)
{
        /* No Endian conversion needed as this data is untouched by hw */
        desc->sw_data[index] = data;
}

/* use these macros to set sw data */
#define SET_SW_DATA0(data, desc) set_sw_data(0, data, desc)
#define SET_SW_DATA1(data, desc) set_sw_data(1, data, desc)
#define SET_SW_DATA2(data, desc) set_sw_data(2, data, desc)
#define SET_SW_DATA3(data, desc) set_sw_data(3, data, desc)

static void set_org_pkt_info(dma_addr_t buff, u32 buff_len,
                             struct knav_dma_desc *desc)
{
        desc->orig_buff = cpu_to_le32(buff);
        desc->orig_len = cpu_to_le32(buff_len);
}

static void set_words(u32 *words, int num_words, __le32 *desc)
{
        int i;

        for (i = 0; i < num_words; i++)
                desc[i] = cpu_to_le32(words[i]);
}

/* Read the e-fuse value as 32 bit values to be endian independent */
static int emac_arch_get_mac_addr(char *x, void __iomem *efuse_mac, u32 swap)
{
        unsigned int addr0, addr1;

        addr1 = readl(efuse_mac + 4);
        addr0 = readl(efuse_mac);

        switch (swap) {
        case NETCP_EFUSE_ADDR_SWAP:
                addr0 = addr1;
                addr1 = readl(efuse_mac);
                break;
        default:
                break;
        }

        x[0] = (addr1 & 0x0000ff00) >> 8;
        x[1] = addr1 & 0x000000ff;
        x[2] = (addr0 & 0xff000000) >> 24;
        x[3] = (addr0 & 0x00ff0000) >> 16;
        x[4] = (addr0 & 0x0000ff00) >> 8;
        x[5] = addr0 & 0x000000ff;

        return 0;
}

static const char *netcp_node_name(struct device_node *node)
{
        const char *name;

        if (of_property_read_string(node, "label", &name) < 0)
                name = node->name;
        if (!name)
                name = "unknown";
        return name;
}

/* Module management routines */
static int netcp_register_interface(struct netcp_intf *netcp)
{
        int ret;

        ret = register_netdev(netcp->ndev);
        if (!ret)
                netcp->netdev_registered = true;
        return ret;
}

static int netcp_module_probe(struct netcp_device *netcp_device,
                              struct netcp_module *module)
{
        struct device *dev = netcp_device->device;
        struct device_node *devices, *interface, *node = dev->of_node;
        struct device_node *child;
        struct netcp_inst_modpriv *inst_modpriv;
        struct netcp_intf *netcp_intf;
        struct netcp_module *tmp;
        bool primary_module_registered = false;
        int ret;

        /* Find this module in the sub-tree for this device */
        devices = of_get_child_by_name(node, "netcp-devices");
        if (!devices) {
                dev_err(dev, "could not find netcp-devices node\n");
                return NETCP_MOD_PROBE_SKIPPED;
        }

        for_each_available_child_of_node(devices, child) {
                const char *name = netcp_node_name(child);

                if (!strcasecmp(module->name, name))
                        break;
        }

        of_node_put(devices);
        /* If module not used for this device, skip it */
        if (!child) {
                dev_warn(dev, "module(%s) not used for device\n", module->name);
                return NETCP_MOD_PROBE_SKIPPED;
        }

        inst_modpriv = devm_kzalloc(dev, sizeof(*inst_modpriv), GFP_KERNEL);
        if (!inst_modpriv) {
                of_node_put(child);
                return -ENOMEM;
        }

        inst_modpriv->netcp_device = netcp_device;
        inst_modpriv->netcp_module = module;
        list_add_tail(&inst_modpriv->inst_list, &netcp_device->modpriv_head);

        ret = module->probe(netcp_device, dev, child,
                            &inst_modpriv->module_priv);
        of_node_put(child);
        if (ret) {
                dev_err(dev, "Probe of module(%s) failed with %d\n",
                        module->name, ret);
                list_del(&inst_modpriv->inst_list);
                devm_kfree(dev, inst_modpriv);
                return NETCP_MOD_PROBE_FAILED;
        }

        /* Attach modules only if the primary module is probed */
        for_each_netcp_module(tmp) {
                if (tmp->primary)
                        primary_module_registered = true;
        }

        if (!primary_module_registered)
                return 0;

        /* Attach module to interfaces */
        list_for_each_entry(netcp_intf, &netcp_device->interface_head,
                            interface_list) {
                struct netcp_intf_modpriv *intf_modpriv;

                intf_modpriv = devm_kzalloc(dev, sizeof(*intf_modpriv),
                                            GFP_KERNEL);
                if (!intf_modpriv)
                        return -ENOMEM;

                interface = of_parse_phandle(netcp_intf->node_interface,
                                             module->name, 0);

                if (!interface) {
                        devm_kfree(dev, intf_modpriv);
                        continue;
                }

                intf_modpriv->netcp_priv = netcp_intf;
                intf_modpriv->netcp_module = module;
                list_add_tail(&intf_modpriv->intf_list,
                              &netcp_intf->module_head);

                ret = module->attach(inst_modpriv->module_priv,
                                     netcp_intf->ndev, interface,
                                     &intf_modpriv->module_priv);
                of_node_put(interface);
                if (ret) {
                        dev_dbg(dev, "Attach of module %s declined with %d\n",
                                module->name, ret);
                        list_del(&intf_modpriv->intf_list);
                        devm_kfree(dev, intf_modpriv);
                        continue;
                }
        }

        /* Now register the interface with netdev */
        list_for_each_entry(netcp_intf,
                            &netcp_device->interface_head,
                            interface_list) {
                /* If interface not registered then register now */
                if (!netcp_intf->netdev_registered) {
                        ret = netcp_register_interface(netcp_intf);
                        if (ret)
                                return -ENODEV;
                }
        }
        return 0;
}

int netcp_register_module(struct netcp_module *module)
{
        struct netcp_device *netcp_device;
        struct netcp_module *tmp;
        int ret;

        if (!module->name) {
                WARN(1, "error registering netcp module: no name\n");
                return -EINVAL;
        }

        if (!module->probe) {
                WARN(1, "error registering netcp module: no probe\n");
                return -EINVAL;
        }

        mutex_lock(&netcp_modules_lock);

        for_each_netcp_module(tmp) {
                if (!strcasecmp(tmp->name, module->name)) {
                        mutex_unlock(&netcp_modules_lock);
                        return -EEXIST;
                }
        }
        list_add_tail(&module->module_list, &netcp_modules);

        list_for_each_entry(netcp_device, &netcp_devices, device_list) {
                ret = netcp_module_probe(netcp_device, module);
                if (ret < 0)
                        goto fail;
        }
        mutex_unlock(&netcp_modules_lock);
        return 0;

fail:
        mutex_unlock(&netcp_modules_lock);
        netcp_unregister_module(module);
        return ret;
}
EXPORT_SYMBOL_GPL(netcp_register_module);

static void netcp_release_module(struct netcp_device *netcp_device,
                                 struct netcp_module *module)
{
        struct netcp_inst_modpriv *inst_modpriv, *inst_tmp;
        struct netcp_intf *netcp_intf, *netcp_tmp;
        struct device *dev = netcp_device->device;

        /* Release the module from each interface */
        list_for_each_entry_safe(netcp_intf, netcp_tmp,
                                 &netcp_device->interface_head,
                                 interface_list) {
                struct netcp_intf_modpriv *intf_modpriv, *intf_tmp;

                list_for_each_entry_safe(intf_modpriv, intf_tmp,
                                         &netcp_intf->module_head,
                                         intf_list) {
                        if (intf_modpriv->netcp_module == module) {
                                module->release(intf_modpriv->module_priv);
                                list_del(&intf_modpriv->intf_list);
                                devm_kfree(dev, intf_modpriv);
                                break;
                        }
                }
        }

        /* Remove the module from each instance */
        list_for_each_entry_safe(inst_modpriv, inst_tmp,
                                 &netcp_device->modpriv_head, inst_list) {
                if (inst_modpriv->netcp_module == module) {
                        module->remove(netcp_device,
                                       inst_modpriv->module_priv);
                        list_del(&inst_modpriv->inst_list);
                        devm_kfree(dev, inst_modpriv);
                        break;
                }
        }
}

void netcp_unregister_module(struct netcp_module *module)
{
        struct netcp_device *netcp_device;
        struct netcp_module *module_tmp;

        mutex_lock(&netcp_modules_lock);

        list_for_each_entry(netcp_device, &netcp_devices, device_list) {
                netcp_release_module(netcp_device, module);
        }

        /* Remove the module from the module list */
        for_each_netcp_module(module_tmp) {
                if (module == module_tmp) {
                        list_del(&module->module_list);
                        break;
                }
        }

        mutex_unlock(&netcp_modules_lock);
}
EXPORT_SYMBOL_GPL(netcp_unregister_module);

void *netcp_module_get_intf_data(struct netcp_module *module,
                                 struct netcp_intf *intf)
{
        struct netcp_intf_modpriv *intf_modpriv;

        list_for_each_entry(intf_modpriv, &intf->module_head, intf_list)
                if (intf_modpriv->netcp_module == module)
                        return intf_modpriv->module_priv;
        return NULL;
}
EXPORT_SYMBOL_GPL(netcp_module_get_intf_data);

/* Module TX and RX Hook management */
struct netcp_hook_list {
        struct list_head         list;
        netcp_hook_rtn          *hook_rtn;
        void                    *hook_data;
        int                      order;
};

int netcp_register_txhook(struct netcp_intf *netcp_priv, int order,
                          netcp_hook_rtn *hook_rtn, void *hook_data)
{
        struct netcp_hook_list *entry;
        struct netcp_hook_list *next;
        unsigned long flags;

        entry = devm_kzalloc(netcp_priv->dev, sizeof(*entry), GFP_KERNEL);
        if (!entry)
                return -ENOMEM;

        entry->hook_rtn  = hook_rtn;
        entry->hook_data = hook_data;
        entry->order     = order;

        spin_lock_irqsave(&netcp_priv->lock, flags);
        list_for_each_entry(next, &netcp_priv->txhook_list_head, list) {
                if (next->order > order)
                        break;
        }
        __list_add(&entry->list, next->list.prev, &next->list);
        spin_unlock_irqrestore(&netcp_priv->lock, flags);

        return 0;
}
EXPORT_SYMBOL_GPL(netcp_register_txhook);

int netcp_unregister_txhook(struct netcp_intf *netcp_priv, int order,
                            netcp_hook_rtn *hook_rtn, void *hook_data)
{
        struct netcp_hook_list *next, *n;
        unsigned long flags;

        spin_lock_irqsave(&netcp_priv->lock, flags);
        list_for_each_entry_safe(next, n, &netcp_priv->txhook_list_head, list) {
                if ((next->order     == order) &&
                    (next->hook_rtn  == hook_rtn) &&
                    (next->hook_data == hook_data)) {
                        list_del(&next->list);
                        spin_unlock_irqrestore(&netcp_priv->lock, flags);
                        devm_kfree(netcp_priv->dev, next);
                        return 0;
                }
        }
        spin_unlock_irqrestore(&netcp_priv->lock, flags);
        return -ENOENT;
}
EXPORT_SYMBOL_GPL(netcp_unregister_txhook);

int netcp_register_rxhook(struct netcp_intf *netcp_priv, int order,
                          netcp_hook_rtn *hook_rtn, void *hook_data)
{
        struct netcp_hook_list *entry;
        struct netcp_hook_list *next;
        unsigned long flags;

        entry = devm_kzalloc(netcp_priv->dev, sizeof(*entry), GFP_KERNEL);
        if (!entry)
                return -ENOMEM;

        entry->hook_rtn  = hook_rtn;
        entry->hook_data = hook_data;
        entry->order     = order;

        spin_lock_irqsave(&netcp_priv->lock, flags);
        list_for_each_entry(next, &netcp_priv->rxhook_list_head, list) {
                if (next->order > order)
                        break;
        }
        __list_add(&entry->list, next->list.prev, &next->list);
        spin_unlock_irqrestore(&netcp_priv->lock, flags);

        return 0;
}
EXPORT_SYMBOL_GPL(netcp_register_rxhook);

int netcp_unregister_rxhook(struct netcp_intf *netcp_priv, int order,
                            netcp_hook_rtn *hook_rtn, void *hook_data)
{
        struct netcp_hook_list *next, *n;
        unsigned long flags;

        spin_lock_irqsave(&netcp_priv->lock, flags);
        list_for_each_entry_safe(next, n, &netcp_priv->rxhook_list_head, list) {
                if ((next->order     == order) &&
                    (next->hook_rtn  == hook_rtn) &&
                    (next->hook_data == hook_data)) {
                        list_del(&next->list);
                        spin_unlock_irqrestore(&netcp_priv->lock, flags);
                        devm_kfree(netcp_priv->dev, next);
                        return 0;
                }
        }
        spin_unlock_irqrestore(&netcp_priv->lock, flags);

        return -ENOENT;
}
EXPORT_SYMBOL_GPL(netcp_unregister_rxhook);

static void netcp_frag_free(bool is_frag, void *ptr)
{
        if (is_frag)
                skb_free_frag(ptr);
        else
                kfree(ptr);
}

static void netcp_free_rx_desc_chain(struct netcp_intf *netcp,
                                     struct knav_dma_desc *desc)
{
        struct knav_dma_desc *ndesc;
        dma_addr_t dma_desc, dma_buf;
        unsigned int buf_len, dma_sz = sizeof(*ndesc);
        void *buf_ptr;
        u32 tmp;

        get_words(&dma_desc, 1, &desc->next_desc);

        while (dma_desc) {
                ndesc = knav_pool_desc_unmap(netcp->rx_pool, dma_desc, dma_sz);
                if (unlikely(!ndesc)) {
                        dev_err(netcp->ndev_dev, "failed to unmap Rx desc\n");
                        break;
                }
                get_pkt_info(&dma_buf, &tmp, &dma_desc, ndesc);
                /* warning!!!! We are retrieving the virtual ptr in the sw_data
                 * field as a 32bit value. Will not work on 64bit machines
                 */
                buf_ptr = (void *)GET_SW_DATA0(ndesc);
                buf_len = (int)GET_SW_DATA1(desc);
                dma_unmap_page(netcp->dev, dma_buf, PAGE_SIZE, DMA_FROM_DEVICE);
                __free_page(buf_ptr);
                knav_pool_desc_put(netcp->rx_pool, desc);
        }
        /* warning!!!! We are retrieving the virtual ptr in the sw_data
         * field as a 32bit value. Will not work on 64bit machines
         */
        buf_ptr = (void *)GET_SW_DATA0(desc);
        buf_len = (int)GET_SW_DATA1(desc);

        if (buf_ptr)
                netcp_frag_free(buf_len <= PAGE_SIZE, buf_ptr);
        knav_pool_desc_put(netcp->rx_pool, desc);
}

static void netcp_empty_rx_queue(struct netcp_intf *netcp)
{
        struct netcp_stats *rx_stats = &netcp->stats;
        struct knav_dma_desc *desc;
        unsigned int dma_sz;
        dma_addr_t dma;

        for (; ;) {
                dma = knav_queue_pop(netcp->rx_queue, &dma_sz);
                if (!dma)
                        break;

                desc = knav_pool_desc_unmap(netcp->rx_pool, dma, dma_sz);
                if (unlikely(!desc)) {
                        dev_err(netcp->ndev_dev, "%s: failed to unmap Rx desc\n",
                                __func__);
                        rx_stats->rx_errors++;
                        continue;
                }
                netcp_free_rx_desc_chain(netcp, desc);
                rx_stats->rx_dropped++;
        }
}

static int netcp_process_one_rx_packet(struct netcp_intf *netcp)
{
        struct netcp_stats *rx_stats = &netcp->stats;
        unsigned int dma_sz, buf_len, org_buf_len;
        struct knav_dma_desc *desc, *ndesc;
        unsigned int pkt_sz = 0, accum_sz;
        struct netcp_hook_list *rx_hook;
        dma_addr_t dma_desc, dma_buff;
        struct netcp_packet p_info;
        struct sk_buff *skb;
        void *org_buf_ptr;
        u32 tmp;

        dma_desc = knav_queue_pop(netcp->rx_queue, &dma_sz);
        if (!dma_desc)
                return -1;

        desc = knav_pool_desc_unmap(netcp->rx_pool, dma_desc, dma_sz);
        if (unlikely(!desc)) {
                dev_err(netcp->ndev_dev, "failed to unmap Rx desc\n");
                return 0;
        }

        get_pkt_info(&dma_buff, &buf_len, &dma_desc, desc);
        /* warning!!!! We are retrieving the virtual ptr in the sw_data
         * field as a 32bit value. Will not work on 64bit machines
         */
        org_buf_ptr = (void *)GET_SW_DATA0(desc);
        org_buf_len = (int)GET_SW_DATA1(desc);

        if (unlikely(!org_buf_ptr)) {
                dev_err(netcp->ndev_dev, "NULL bufptr in desc\n");
                goto free_desc;
        }

        pkt_sz &= KNAV_DMA_DESC_PKT_LEN_MASK;
        accum_sz = buf_len;
        dma_unmap_single(netcp->dev, dma_buff, buf_len, DMA_FROM_DEVICE);

        /* Build a new sk_buff for the primary buffer */
        skb = build_skb(org_buf_ptr, org_buf_len);
        if (unlikely(!skb)) {
                dev_err(netcp->ndev_dev, "build_skb() failed\n");
                goto free_desc;
        }

        /* update data, tail and len */
        skb_reserve(skb, NETCP_SOP_OFFSET);
        __skb_put(skb, buf_len);

        /* Fill in the page fragment list */
        while (dma_desc) {
                struct page *page;

                ndesc = knav_pool_desc_unmap(netcp->rx_pool, dma_desc, dma_sz);
                if (unlikely(!ndesc)) {
                        dev_err(netcp->ndev_dev, "failed to unmap Rx desc\n");
                        goto free_desc;
                }

                get_pkt_info(&dma_buff, &buf_len, &dma_desc, ndesc);
                /* warning!!!! We are retrieving the virtual ptr in the sw_data
                 * field as a 32bit value. Will not work on 64bit machines
                 */
                page = (struct page *)GET_SW_DATA0(ndesc);

                if (likely(dma_buff && buf_len && page)) {
                        dma_unmap_page(netcp->dev, dma_buff, PAGE_SIZE,
                                       DMA_FROM_DEVICE);
                } else {
                        dev_err(netcp->ndev_dev, "Bad Rx desc dma_buff(%pad), len(%d), page(%p)\n",
                                &dma_buff, buf_len, page);
                        goto free_desc;
                }

                skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page,
                                offset_in_page(dma_buff), buf_len, PAGE_SIZE);
                accum_sz += buf_len;

                /* Free the descriptor */
                knav_pool_desc_put(netcp->rx_pool, ndesc);
        }

        /* check for packet len and warn */
        if (unlikely(pkt_sz != accum_sz))
                dev_dbg(netcp->ndev_dev, "mismatch in packet size(%d) & sum of fragments(%d)\n",
                        pkt_sz, accum_sz);

        /* Newer version of the Ethernet switch can trim the Ethernet FCS
         * from the packet and is indicated in hw_cap. So trim it only for
         * older h/w
         */
        if (!(netcp->hw_cap & ETH_SW_CAN_REMOVE_ETH_FCS))
                __pskb_trim(skb, skb->len - ETH_FCS_LEN);

        /* Call each of the RX hooks */
        p_info.skb = skb;
        skb->dev = netcp->ndev;
        p_info.rxtstamp_complete = false;
        get_desc_info(&tmp, &p_info.eflags, desc);
        p_info.epib = desc->epib;
        p_info.psdata = (u32 __force *)desc->psdata;
        p_info.eflags = ((p_info.eflags >> KNAV_DMA_DESC_EFLAGS_SHIFT) &
                         KNAV_DMA_DESC_EFLAGS_MASK);
        list_for_each_entry(rx_hook, &netcp->rxhook_list_head, list) {
                int ret;

                ret = rx_hook->hook_rtn(rx_hook->order, rx_hook->hook_data,
                                        &p_info);
                if (unlikely(ret)) {
                        dev_err(netcp->ndev_dev, "RX hook %d failed: %d\n",
                                rx_hook->order, ret);
                        /* Free the primary descriptor */
                        rx_stats->rx_dropped++;
                        knav_pool_desc_put(netcp->rx_pool, desc);
                        dev_kfree_skb(skb);
                        return 0;
                }
        }
        /* Free the primary descriptor */
        knav_pool_desc_put(netcp->rx_pool, desc);

        u64_stats_update_begin(&rx_stats->syncp_rx);
        rx_stats->rx_packets++;
        rx_stats->rx_bytes += skb->len;
        u64_stats_update_end(&rx_stats->syncp_rx);

        /* push skb up the stack */
        skb->protocol = eth_type_trans(skb, netcp->ndev);
        netif_receive_skb(skb);
        return 0;

free_desc:
        netcp_free_rx_desc_chain(netcp, desc);
        rx_stats->rx_errors++;
        return 0;
}

static int netcp_process_rx_packets(struct netcp_intf *netcp,
                                    unsigned int budget)
{
        int i;

        for (i = 0; (i < budget) && !netcp_process_one_rx_packet(netcp); i++)
                ;
        return i;
}

/* Release descriptors and attached buffers from Rx FDQ */
static void netcp_free_rx_buf(struct netcp_intf *netcp, int fdq)
{
        struct knav_dma_desc *desc;
        unsigned int buf_len, dma_sz;
        dma_addr_t dma;
        void *buf_ptr;

        /* Allocate descriptor */
        while ((dma = knav_queue_pop(netcp->rx_fdq[fdq], &dma_sz))) {
                desc = knav_pool_desc_unmap(netcp->rx_pool, dma, dma_sz);
                if (unlikely(!desc)) {
                        dev_err(netcp->ndev_dev, "failed to unmap Rx desc\n");
                        continue;
                }

                get_org_pkt_info(&dma, &buf_len, desc);
                /* warning!!!! We are retrieving the virtual ptr in the sw_data
                 * field as a 32bit value. Will not work on 64bit machines
                 */
                buf_ptr = (void *)GET_SW_DATA0(desc);

                if (unlikely(!dma)) {
                        dev_err(netcp->ndev_dev, "NULL orig_buff in desc\n");
                        knav_pool_desc_put(netcp->rx_pool, desc);
                        continue;
                }

                if (unlikely(!buf_ptr)) {
                        dev_err(netcp->ndev_dev, "NULL bufptr in desc\n");
                        knav_pool_desc_put(netcp->rx_pool, desc);
                        continue;
                }

                if (fdq == 0) {
                        dma_unmap_single(netcp->dev, dma, buf_len,
                                         DMA_FROM_DEVICE);
                        netcp_frag_free((buf_len <= PAGE_SIZE), buf_ptr);
                } else {
                        dma_unmap_page(netcp->dev, dma, buf_len,
                                       DMA_FROM_DEVICE);
                        __free_page(buf_ptr);
                }

                knav_pool_desc_put(netcp->rx_pool, desc);
        }
}

static void netcp_rxpool_free(struct netcp_intf *netcp)
{
        int i;

        for (i = 0; i < KNAV_DMA_FDQ_PER_CHAN &&
             !IS_ERR_OR_NULL(netcp->rx_fdq[i]); i++)
                netcp_free_rx_buf(netcp, i);

        if (knav_pool_count(netcp->rx_pool) != netcp->rx_pool_size)
                dev_err(netcp->ndev_dev, "Lost Rx (%d) descriptors\n",
                        netcp->rx_pool_size - knav_pool_count(netcp->rx_pool));

        knav_pool_destroy(netcp->rx_pool);
        netcp->rx_pool = NULL;
}

static int netcp_allocate_rx_buf(struct netcp_intf *netcp, int fdq)
{
        struct knav_dma_desc *hwdesc;
        unsigned int buf_len, dma_sz;
        u32 desc_info, pkt_info;
        struct page *page;
        dma_addr_t dma;
        void *bufptr;
        u32 sw_data[2];

        /* Allocate descriptor */
        hwdesc = knav_pool_desc_get(netcp->rx_pool);
        if (IS_ERR_OR_NULL(hwdesc)) {
                dev_dbg(netcp->ndev_dev, "out of rx pool desc\n");
                return -ENOMEM;
        }

        if (likely(fdq == 0)) {
                unsigned int primary_buf_len;
                /* Allocate a primary receive queue entry */
                buf_len = NETCP_PACKET_SIZE + NETCP_SOP_OFFSET;
                primary_buf_len = SKB_DATA_ALIGN(buf_len) +
                                SKB_DATA_ALIGN(sizeof(struct skb_shared_info));

                bufptr = netdev_alloc_frag(primary_buf_len);
                sw_data[1] = primary_buf_len;

                if (unlikely(!bufptr)) {
                        dev_warn_ratelimited(netcp->ndev_dev,
                                             "Primary RX buffer alloc failed\n");
                        goto fail;
                }
                dma = dma_map_single(netcp->dev, bufptr, buf_len,
                                     DMA_TO_DEVICE);
                if (unlikely(dma_mapping_error(netcp->dev, dma)))
                        goto fail;

                /* warning!!!! We are saving the virtual ptr in the sw_data
                 * field as a 32bit value. Will not work on 64bit machines
                 */
                sw_data[0] = (u32)bufptr;
        } else {
                /* Allocate a secondary receive queue entry */
                page = alloc_page(GFP_ATOMIC | GFP_DMA);
                if (unlikely(!page)) {
                        dev_warn_ratelimited(netcp->ndev_dev, "Secondary page alloc failed\n");
                        goto fail;
                }
                buf_len = PAGE_SIZE;
                dma = dma_map_page(netcp->dev, page, 0, buf_len, DMA_TO_DEVICE);
                /* warning!!!! We are saving the virtual ptr in the sw_data
                 * field as a 32bit value. Will not work on 64bit machines
                 */
                sw_data[0] = (u32)page;
                sw_data[1] = 0;
        }

        desc_info =  KNAV_DMA_DESC_PS_INFO_IN_DESC;
        desc_info |= buf_len & KNAV_DMA_DESC_PKT_LEN_MASK;
        pkt_info =  KNAV_DMA_DESC_HAS_EPIB;
        pkt_info |= KNAV_DMA_NUM_PS_WORDS << KNAV_DMA_DESC_PSLEN_SHIFT;
        pkt_info |= (netcp->rx_queue_id & KNAV_DMA_DESC_RETQ_MASK) <<
                    KNAV_DMA_DESC_RETQ_SHIFT;
        set_org_pkt_info(dma, buf_len, hwdesc);
        SET_SW_DATA0(sw_data[0], hwdesc);
        SET_SW_DATA1(sw_data[1], hwdesc);
        set_desc_info(desc_info, pkt_info, hwdesc);

        /* Push to FDQs */
        knav_pool_desc_map(netcp->rx_pool, hwdesc, sizeof(*hwdesc), &dma,
                           &dma_sz);
        knav_queue_push(netcp->rx_fdq[fdq], dma, sizeof(*hwdesc), 0);
        return 0;

fail:
        knav_pool_desc_put(netcp->rx_pool, hwdesc);
        return -ENOMEM;
}

/* Refill Rx FDQ with descriptors & attached buffers */
static void netcp_rxpool_refill(struct netcp_intf *netcp)
{
        u32 fdq_deficit[KNAV_DMA_FDQ_PER_CHAN] = {0};
        int i, ret = 0;

        /* Calculate the FDQ deficit and refill */
        for (i = 0; i < KNAV_DMA_FDQ_PER_CHAN && netcp->rx_fdq[i]; i++) {
                fdq_deficit[i] = netcp->rx_queue_depths[i] -
                                 knav_queue_get_count(netcp->rx_fdq[i]);

                while (fdq_deficit[i]-- && !ret)
                        ret = netcp_allocate_rx_buf(netcp, i);
        } /* end for fdqs */
}

/* NAPI poll */
static int netcp_rx_poll(struct napi_struct *napi, int budget)
{
        struct netcp_intf *netcp = container_of(napi, struct netcp_intf,
                                                rx_napi);
        unsigned int packets;

        packets = netcp_process_rx_packets(netcp, budget);

        netcp_rxpool_refill(netcp);
        if (packets < budget) {
                napi_complete_done(&netcp->rx_napi, packets);
                knav_queue_enable_notify(netcp->rx_queue);
        }

        return packets;
}

static void netcp_rx_notify(void *arg)
{
        struct netcp_intf *netcp = arg;

        knav_queue_disable_notify(netcp->rx_queue);
        napi_schedule(&netcp->rx_napi);
}

static void netcp_free_tx_desc_chain(struct netcp_intf *netcp,
                                     struct knav_dma_desc *desc,
                                     unsigned int desc_sz)
{
        struct knav_dma_desc *ndesc = desc;
        dma_addr_t dma_desc, dma_buf;
        unsigned int buf_len;

        while (ndesc) {
                get_pkt_info(&dma_buf, &buf_len, &dma_desc, ndesc);

                if (dma_buf && buf_len)
                        dma_unmap_single(netcp->dev, dma_buf, buf_len,
                                         DMA_TO_DEVICE);

                else
                        dev_warn(netcp->ndev_dev, "bad Tx desc buf(%pad), len(%d)\n",
                                 &dma_buf, buf_len);

                knav_pool_desc_put(netcp->tx_pool, ndesc);
                ndesc = NULL;
                if (dma_desc) {
                        ndesc = knav_pool_desc_unmap(netcp->tx_pool, dma_desc,
                                                     desc_sz);
                        if (!ndesc)
                                dev_err(netcp->ndev_dev, "failed to unmap Tx desc\n");
                }
        }
}

static int netcp_process_tx_compl_packets(struct netcp_intf *netcp,
                                          unsigned int budget)
{
        struct netcp_stats *tx_stats = &netcp->stats;
        struct knav_dma_desc *desc;
        struct netcp_tx_cb *tx_cb;
        struct sk_buff *skb;
        unsigned int dma_sz;
        dma_addr_t dma;
        int pkts = 0;

        while (budget--) {
                dma = knav_queue_pop(netcp->tx_compl_q, &dma_sz);
                if (!dma)
                        break;
                desc = knav_pool_desc_unmap(netcp->tx_pool, dma, dma_sz);
                if (unlikely(!desc)) {
                        dev_err(netcp->ndev_dev, "failed to unmap Tx desc\n");
                        tx_stats->tx_errors++;
                        continue;
                }

                /* warning!!!! We are retrieving the virtual ptr in the sw_data
                 * field as a 32bit value. Will not work on 64bit machines
                 */
                skb = (struct sk_buff *)GET_SW_DATA0(desc);
                netcp_free_tx_desc_chain(netcp, desc, dma_sz);
                if (!skb) {
                        dev_err(netcp->ndev_dev, "No skb in Tx desc\n");
                        tx_stats->tx_errors++;
                        continue;
                }

                tx_cb = (struct netcp_tx_cb *)skb->cb;
                if (tx_cb->txtstamp)
                        tx_cb->txtstamp(tx_cb->ts_context, skb);

                if (netif_subqueue_stopped(netcp->ndev, skb) &&
                    netif_running(netcp->ndev) &&
                    (knav_pool_count(netcp->tx_pool) >
                    netcp->tx_resume_threshold)) {
                        u16 subqueue = skb_get_queue_mapping(skb);

                        netif_wake_subqueue(netcp->ndev, subqueue);
                }

                u64_stats_update_begin(&tx_stats->syncp_tx);
                tx_stats->tx_packets++;
                tx_stats->tx_bytes += skb->len;
                u64_stats_update_end(&tx_stats->syncp_tx);
                dev_kfree_skb(skb);
                pkts++;
        }
        return pkts;
}

static int netcp_tx_poll(struct napi_struct *napi, int budget)
{
        int packets;
        struct netcp_intf *netcp = container_of(napi, struct netcp_intf,
                                                tx_napi);

        packets = netcp_process_tx_compl_packets(netcp, budget);
        if (packets < budget) {
                napi_complete(&netcp->tx_napi);
                knav_queue_enable_notify(netcp->tx_compl_q);
        }

        return packets;
}

static void netcp_tx_notify(void *arg)
{
        struct netcp_intf *netcp = arg;

        knav_queue_disable_notify(netcp->tx_compl_q);
        napi_schedule(&netcp->tx_napi);
}

static struct knav_dma_desc*
netcp_tx_map_skb(struct sk_buff *skb, struct netcp_intf *netcp)
{
        struct knav_dma_desc *desc, *ndesc, *pdesc;
        unsigned int pkt_len = skb_headlen(skb);
        struct device *dev = netcp->dev;
        dma_addr_t dma_addr;
        unsigned int dma_sz;
        int i;

        /* Map the linear buffer */
        dma_addr = dma_map_single(dev, skb->data, pkt_len, DMA_TO_DEVICE);
        if (unlikely(dma_mapping_error(dev, dma_addr))) {
                dev_err(netcp->ndev_dev, "Failed to map skb buffer\n");
                return NULL;
        }

        desc = knav_pool_desc_get(netcp->tx_pool);
        if (IS_ERR_OR_NULL(desc)) {
                dev_err(netcp->ndev_dev, "out of TX desc\n");
                dma_unmap_single(dev, dma_addr, pkt_len, DMA_TO_DEVICE);
                return NULL;
        }

        set_pkt_info(dma_addr, pkt_len, 0, desc);
        if (skb_is_nonlinear(skb)) {
                prefetchw(skb_shinfo(skb));
        } else {
                desc->next_desc = 0;
                goto upd_pkt_len;
        }

        pdesc = desc;

        /* Handle the case where skb is fragmented in pages */
        for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
                skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
                struct page *page = skb_frag_page(frag);
                u32 page_offset = frag->page_offset;
                u32 buf_len = skb_frag_size(frag);
                dma_addr_t desc_dma;
                u32 desc_dma_32;

                dma_addr = dma_map_page(dev, page, page_offset, buf_len,
                                        DMA_TO_DEVICE);
                if (unlikely(!dma_addr)) {
                        dev_err(netcp->ndev_dev, "Failed to map skb page\n");
                        goto free_descs;
                }

                ndesc = knav_pool_desc_get(netcp->tx_pool);
                if (IS_ERR_OR_NULL(ndesc)) {
                        dev_err(netcp->ndev_dev, "out of TX desc for frags\n");
                        dma_unmap_page(dev, dma_addr, buf_len, DMA_TO_DEVICE);
                        goto free_descs;
                }

                desc_dma = knav_pool_desc_virt_to_dma(netcp->tx_pool, ndesc);
                set_pkt_info(dma_addr, buf_len, 0, ndesc);
                desc_dma_32 = (u32)desc_dma;
                set_words(&desc_dma_32, 1, &pdesc->next_desc);
                pkt_len += buf_len;
                if (pdesc != desc)
                        knav_pool_desc_map(netcp->tx_pool, pdesc,
                                           sizeof(*pdesc), &desc_dma, &dma_sz);
                pdesc = ndesc;
        }
        if (pdesc != desc)
                knav_pool_desc_map(netcp->tx_pool, pdesc, sizeof(*pdesc),
                                   &dma_addr, &dma_sz);

        /* frag list based linkage is not supported for now. */
        if (skb_shinfo(skb)->frag_list) {
                dev_err_ratelimited(netcp->ndev_dev, "NETIF_F_FRAGLIST not supported\n");
                goto free_descs;
        }

upd_pkt_len:
        WARN_ON(pkt_len != skb->len);

        pkt_len &= KNAV_DMA_DESC_PKT_LEN_MASK;
        set_words(&pkt_len, 1, &desc->desc_info);
        return desc;

free_descs:
        netcp_free_tx_desc_chain(netcp, desc, sizeof(*desc));
        return NULL;
}

static int netcp_tx_submit_skb(struct netcp_intf *netcp,
                               struct sk_buff *skb,
                               struct knav_dma_desc *desc)
{
        struct netcp_tx_pipe *tx_pipe = NULL;
        struct netcp_hook_list *tx_hook;
        struct netcp_packet p_info;
        struct netcp_tx_cb *tx_cb;
        unsigned int dma_sz;
        dma_addr_t dma;
        u32 tmp = 0;
        int ret = 0;

        p_info.netcp = netcp;
        p_info.skb = skb;
        p_info.tx_pipe = NULL;
        p_info.psdata_len = 0;
        p_info.ts_context = NULL;
        p_info.txtstamp = NULL;
        p_info.epib = desc->epib;
        p_info.psdata = (u32 __force *)desc->psdata;
        memset(p_info.epib, 0, KNAV_DMA_NUM_EPIB_WORDS * sizeof(__le32));

        /* Find out where to inject the packet for transmission */
        list_for_each_entry(tx_hook, &netcp->txhook_list_head, list) {
                ret = tx_hook->hook_rtn(tx_hook->order, tx_hook->hook_data,
                                        &p_info);
                if (unlikely(ret != 0)) {
                        dev_err(netcp->ndev_dev, "TX hook %d rejected the packet with reason(%d)\n",
                                tx_hook->order, ret);
                        ret = (ret < 0) ? ret : NETDEV_TX_OK;
                        goto out;
                }
        }

        /* Make sure some TX hook claimed the packet */
        tx_pipe = p_info.tx_pipe;
        if (!tx_pipe) {
                dev_err(netcp->ndev_dev, "No TX hook claimed the packet!\n");
                ret = -ENXIO;
                goto out;
        }

        tx_cb = (struct netcp_tx_cb *)skb->cb;
        tx_cb->ts_context = p_info.ts_context;
        tx_cb->txtstamp = p_info.txtstamp;

        /* update descriptor */
        if (p_info.psdata_len) {
                /* psdata points to both native-endian and device-endian data */
                __le32 *psdata = (void __force *)p_info.psdata;

                set_words((u32 *)psdata +
                          (KNAV_DMA_NUM_PS_WORDS - p_info.psdata_len),
                          p_info.psdata_len, psdata);
                tmp |= (p_info.psdata_len & KNAV_DMA_DESC_PSLEN_MASK) <<
                        KNAV_DMA_DESC_PSLEN_SHIFT;
        }

        tmp |= KNAV_DMA_DESC_HAS_EPIB |
                ((netcp->tx_compl_qid & KNAV_DMA_DESC_RETQ_MASK) <<
                KNAV_DMA_DESC_RETQ_SHIFT);

        if (!(tx_pipe->flags & SWITCH_TO_PORT_IN_TAGINFO)) {
                tmp |= ((tx_pipe->switch_to_port & KNAV_DMA_DESC_PSFLAG_MASK) <<
                        KNAV_DMA_DESC_PSFLAG_SHIFT);
        }

        set_words(&tmp, 1, &desc->packet_info);
        /* warning!!!! We are saving the virtual ptr in the sw_data
         * field as a 32bit value. Will not work on 64bit machines
         */
        SET_SW_DATA0((u32)skb, desc);

        if (tx_pipe->flags & SWITCH_TO_PORT_IN_TAGINFO) {
                tmp = tx_pipe->switch_to_port;
                set_words(&tmp, 1, &desc->tag_info);
        }

        /* submit packet descriptor */
        ret = knav_pool_desc_map(netcp->tx_pool, desc, sizeof(*desc), &dma,
                                 &dma_sz);
        if (unlikely(ret)) {
                dev_err(netcp->ndev_dev, "%s() failed to map desc\n", __func__);
                ret = -ENOMEM;
                goto out;
        }
        skb_tx_timestamp(skb);
        knav_queue_push(tx_pipe->dma_queue, dma, dma_sz, 0);

out:
        return ret;
}

/* Submit the packet */
static int netcp_ndo_start_xmit(struct sk_buff *skb, struct net_device *ndev)
{
        struct netcp_intf *netcp = netdev_priv(ndev);
        struct netcp_stats *tx_stats = &netcp->stats;
        int subqueue = skb_get_queue_mapping(skb);
        struct knav_dma_desc *desc;
        int desc_count, ret = 0;

        if (unlikely(skb->len <= 0)) {
                dev_kfree_skb(skb);
                return NETDEV_TX_OK;
        }

        if (unlikely(skb->len < NETCP_MIN_PACKET_SIZE)) {
                ret = skb_padto(skb, NETCP_MIN_PACKET_SIZE);
                if (ret < 0) {
                        /* If we get here, the skb has already been dropped */
                        dev_warn(netcp->ndev_dev, "padding failed (%d), packet dropped\n",
                                 ret);
                        tx_stats->tx_dropped++;
                        return ret;
                }
                skb->len = NETCP_MIN_PACKET_SIZE;
        }

        desc = netcp_tx_map_skb(skb, netcp);
        if (unlikely(!desc)) {
                netif_stop_subqueue(ndev, subqueue);
                ret = -ENOBUFS;
                goto drop;
        }

        ret = netcp_tx_submit_skb(netcp, skb, desc);
        if (ret)
                goto drop;

        /* Check Tx pool count & stop subqueue if needed */
        desc_count = knav_pool_count(netcp->tx_pool);
        if (desc_count < netcp->tx_pause_threshold) {
                dev_dbg(netcp->ndev_dev, "pausing tx, count(%d)\n", desc_count);
                netif_stop_subqueue(ndev, subqueue);
        }
        return NETDEV_TX_OK;

drop:
        tx_stats->tx_dropped++;
        if (desc)
                netcp_free_tx_desc_chain(netcp, desc, sizeof(*desc));
        dev_kfree_skb(skb);
        return ret;
}

int netcp_txpipe_close(struct netcp_tx_pipe *tx_pipe)
{
        if (tx_pipe->dma_channel) {
                knav_dma_close_channel(tx_pipe->dma_channel);
                tx_pipe->dma_channel = NULL;
        }
        return 0;
}
EXPORT_SYMBOL_GPL(netcp_txpipe_close);

int netcp_txpipe_open(struct netcp_tx_pipe *tx_pipe)
{
        struct device *dev = tx_pipe->netcp_device->device;
        struct knav_dma_cfg config;
        int ret = 0;
        u8 name[16];

        memset(&config, 0, sizeof(config));
        config.direction = DMA_MEM_TO_DEV;
        config.u.tx.filt_einfo = false;
        config.u.tx.filt_pswords = false;
        config.u.tx.priority = DMA_PRIO_MED_L;

        tx_pipe->dma_channel = knav_dma_open_channel(dev,
                                tx_pipe->dma_chan_name, &config);
        if (IS_ERR(tx_pipe->dma_channel)) {
                dev_err(dev, "failed opening tx chan(%s)\n",
                        tx_pipe->dma_chan_name);
                ret = PTR_ERR(tx_pipe->dma_channel);
                goto err;
        }

        snprintf(name, sizeof(name), "tx-pipe-%s", dev_name(dev));
        tx_pipe->dma_queue = knav_queue_open(name, tx_pipe->dma_queue_id,
                                             KNAV_QUEUE_SHARED);
        if (IS_ERR(tx_pipe->dma_queue)) {
                dev_err(dev, "Could not open DMA queue for channel \"%s\": %d\n",
                        name, ret);
                ret = PTR_ERR(tx_pipe->dma_queue);
                goto err;
        }

        dev_dbg(dev, "opened tx pipe %s\n", name);
        return 0;

err:
        if (!IS_ERR_OR_NULL(tx_pipe->dma_channel))
                knav_dma_close_channel(tx_pipe->dma_channel);
        tx_pipe->dma_channel = NULL;
        return ret;
}
EXPORT_SYMBOL_GPL(netcp_txpipe_open);

int netcp_txpipe_init(struct netcp_tx_pipe *tx_pipe,
                      struct netcp_device *netcp_device,
                      const char *dma_chan_name, unsigned int dma_queue_id)
{
        memset(tx_pipe, 0, sizeof(*tx_pipe));
        tx_pipe->netcp_device = netcp_device;
        tx_pipe->dma_chan_name = dma_chan_name;
        tx_pipe->dma_queue_id = dma_queue_id;
        return 0;
}
EXPORT_SYMBOL_GPL(netcp_txpipe_init);

static struct netcp_addr *netcp_addr_find(struct netcp_intf *netcp,
                                          const u8 *addr,
                                          enum netcp_addr_type type)
{
        struct netcp_addr *naddr;

        list_for_each_entry(naddr, &netcp->addr_list, node) {
                if (naddr->type != type)
                        continue;
                if (addr && memcmp(addr, naddr->addr, ETH_ALEN))
                        continue;
                return naddr;
        }

        return NULL;
}

static struct netcp_addr *netcp_addr_add(struct netcp_intf *netcp,
                                         const u8 *addr,
                                         enum netcp_addr_type type)
{
        struct netcp_addr *naddr;

        naddr = devm_kmalloc(netcp->dev, sizeof(*naddr), GFP_ATOMIC);
        if (!naddr)
                return NULL;

        naddr->type = type;
        naddr->flags = 0;
        naddr->netcp = netcp;
        if (addr)
                ether_addr_copy(naddr->addr, addr);
        else
                eth_zero_addr(naddr->addr);
        list_add_tail(&naddr->node, &netcp->addr_list);

        return naddr;
}

static void netcp_addr_del(struct netcp_intf *netcp, struct netcp_addr *naddr)
{
        list_del(&naddr->node);
        devm_kfree(netcp->dev, naddr);
}

static void netcp_addr_clear_mark(struct netcp_intf *netcp)
{
        struct netcp_addr *naddr;

        list_for_each_entry(naddr, &netcp->addr_list, node)
                naddr->flags = 0;
}

static void netcp_addr_add_mark(struct netcp_intf *netcp, const u8 *addr,
                                enum netcp_addr_type type)
{
        struct netcp_addr *naddr;

        naddr = netcp_addr_find(netcp, addr, type);
        if (naddr) {
                naddr->flags |= ADDR_VALID;
                return;
        }

        naddr = netcp_addr_add(netcp, addr, type);
        if (!WARN_ON(!naddr))
                naddr->flags |= ADDR_NEW;
}

static void netcp_addr_sweep_del(struct netcp_intf *netcp)
{
        struct netcp_addr *naddr, *tmp;
        struct netcp_intf_modpriv *priv;
        struct netcp_module *module;
        int error;

        list_for_each_entry_safe(naddr, tmp, &netcp->addr_list, node) {
                if (naddr->flags & (ADDR_VALID | ADDR_NEW))
                        continue;
                dev_dbg(netcp->ndev_dev, "deleting address %pM, type %x\n",
                        naddr->addr, naddr->type);
                for_each_module(netcp, priv) {
                        module = priv->netcp_module;
                        if (!module->del_addr)
                                continue;
                        error = module->del_addr(priv->module_priv,
                                                 naddr);
                        WARN_ON(error);
                }
                netcp_addr_del(netcp, naddr);
        }
}

static void netcp_addr_sweep_add(struct netcp_intf *netcp)
{
        struct netcp_addr *naddr, *tmp;
        struct netcp_intf_modpriv *priv;
        struct netcp_module *module;
        int error;

        list_for_each_entry_safe(naddr, tmp, &netcp->addr_list, node) {
                if (!(naddr->flags & ADDR_NEW))
                        continue;
                dev_dbg(netcp->ndev_dev, "adding address %pM, type %x\n",
                        naddr->addr, naddr->type);

                for_each_module(netcp, priv) {
                        module = priv->netcp_module;
                        if (!module->add_addr)
                                continue;
                        error = module->add_addr(priv->module_priv, naddr);
                        WARN_ON(error);
                }
        }
}

static void netcp_set_rx_mode(struct net_device *ndev)
{
        struct netcp_intf *netcp = netdev_priv(ndev);
        struct netdev_hw_addr *ndev_addr;
        bool promisc;

        promisc = (ndev->flags & IFF_PROMISC ||
                   ndev->flags & IFF_ALLMULTI ||
                   netdev_mc_count(ndev) > NETCP_MAX_MCAST_ADDR);

        spin_lock(&netcp->lock);
        /* first clear all marks */
        netcp_addr_clear_mark(netcp);

        /* next add new entries, mark existing ones */
        netcp_addr_add_mark(netcp, ndev->broadcast, ADDR_BCAST);
        for_each_dev_addr(ndev, ndev_addr)
                netcp_addr_add_mark(netcp, ndev_addr->addr, ADDR_DEV);
        netdev_for_each_uc_addr(ndev_addr, ndev)
                netcp_addr_add_mark(netcp, ndev_addr->addr, ADDR_UCAST);
        netdev_for_each_mc_addr(ndev_addr, ndev)
                netcp_addr_add_mark(netcp, ndev_addr->addr, ADDR_MCAST);

        if (promisc)
                netcp_addr_add_mark(netcp, NULL, ADDR_ANY);

        /* finally sweep and callout into modules */
        netcp_addr_sweep_del(netcp);
        netcp_addr_sweep_add(netcp);
        spin_unlock(&netcp->lock);
}

static void netcp_free_navigator_resources(struct netcp_intf *netcp)
{
        int i;

        if (netcp->rx_channel) {
                knav_dma_close_channel(netcp->rx_channel);
                netcp->rx_channel = NULL;
        }

        if (!IS_ERR_OR_NULL(netcp->rx_pool))
                netcp_rxpool_free(netcp);

        if (!IS_ERR_OR_NULL(netcp->rx_queue)) {
                knav_queue_close(netcp->rx_queue);
                netcp->rx_queue = NULL;
        }

        for (i = 0; i < KNAV_DMA_FDQ_PER_CHAN &&
             !IS_ERR_OR_NULL(netcp->rx_fdq[i]) ; ++i) {
                knav_queue_close(netcp->rx_fdq[i]);
                netcp->rx_fdq[i] = NULL;
        }

        if (!IS_ERR_OR_NULL(netcp->tx_compl_q)) {
                knav_queue_close(netcp->tx_compl_q);
                netcp->tx_compl_q = NULL;
        }

        if (!IS_ERR_OR_NULL(netcp->tx_pool)) {
                knav_pool_destroy(netcp->tx_pool);
                netcp->tx_pool = NULL;
        }
}

static int netcp_setup_navigator_resources(struct net_device *ndev)
{
        struct netcp_intf *netcp = netdev_priv(ndev);
        struct knav_queue_notify_config notify_cfg;
        struct knav_dma_cfg config;
        u32 last_fdq = 0;
        u8 name[16];
        int ret;
        int i;

        /* Create Rx/Tx descriptor pools */
        snprintf(name, sizeof(name), "rx-pool-%s", ndev->name);
        netcp->rx_pool = knav_pool_create(name, netcp->rx_pool_size,
                                                netcp->rx_pool_region_id);
        if (IS_ERR_OR_NULL(netcp->rx_pool)) {
                dev_err(netcp->ndev_dev, "Couldn't create rx pool\n");
                ret = PTR_ERR(netcp->rx_pool);
                goto fail;
        }

        snprintf(name, sizeof(name), "tx-pool-%s", ndev->name);
        netcp->tx_pool = knav_pool_create(name, netcp->tx_pool_size,
                                                netcp->tx_pool_region_id);
        if (IS_ERR_OR_NULL(netcp->tx_pool)) {
                dev_err(netcp->ndev_dev, "Couldn't create tx pool\n");
                ret = PTR_ERR(netcp->tx_pool);
                goto fail;
        }

        /* open Tx completion queue */
        snprintf(name, sizeof(name), "tx-compl-%s", ndev->name);
        netcp->tx_compl_q = knav_queue_open(name, netcp->tx_compl_qid, 0);
        if (IS_ERR(netcp->tx_compl_q)) {
                ret = PTR_ERR(netcp->tx_compl_q);
                goto fail;
        }
        netcp->tx_compl_qid = knav_queue_get_id(netcp->tx_compl_q);

        /* Set notification for Tx completion */
        notify_cfg.fn = netcp_tx_notify;
        notify_cfg.fn_arg = netcp;
        ret = knav_queue_device_control(netcp->tx_compl_q,
                                        KNAV_QUEUE_SET_NOTIFIER,
                                        (unsigned long)&notify_cfg);
        if (ret)
                goto fail;

        knav_queue_disable_notify(netcp->tx_compl_q);

        /* open Rx completion queue */
        snprintf(name, sizeof(name), "rx-compl-%s", ndev->name);
        netcp->rx_queue = knav_queue_open(name, netcp->rx_queue_id, 0);
        if (IS_ERR(netcp->rx_queue)) {
                ret = PTR_ERR(netcp->rx_queue);
                goto fail;
        }
        netcp->rx_queue_id = knav_queue_get_id(netcp->rx_queue);

        /* Set notification for Rx completion */
        notify_cfg.fn = netcp_rx_notify;
        notify_cfg.fn_arg = netcp;
        ret = knav_queue_device_control(netcp->rx_queue,
                                        KNAV_QUEUE_SET_NOTIFIER,
                                        (unsigned long)&notify_cfg);
        if (ret)
                goto fail;

        knav_queue_disable_notify(netcp->rx_queue);

        /* open Rx FDQs */
        for (i = 0; i < KNAV_DMA_FDQ_PER_CHAN && netcp->rx_queue_depths[i];
             ++i) {
                snprintf(name, sizeof(name), "rx-fdq-%s-%d", ndev->name, i);
                netcp->rx_fdq[i] = knav_queue_open(name, KNAV_QUEUE_GP, 0);
                if (IS_ERR(netcp->rx_fdq[i])) {
                        ret = PTR_ERR(netcp->rx_fdq[i]);
                        goto fail;
                }
        }

        memset(&config, 0, sizeof(config));
        config.direction                = DMA_DEV_TO_MEM;
        config.u.rx.einfo_present       = true;
        config.u.rx.psinfo_present      = true;
        config.u.rx.err_mode            = DMA_DROP;
        config.u.rx.desc_type           = DMA_DESC_HOST;
        config.u.rx.psinfo_at_sop       = false;
        config.u.rx.sop_offset          = NETCP_SOP_OFFSET;
        config.u.rx.dst_q               = netcp->rx_queue_id;
        config.u.rx.thresh              = DMA_THRESH_NONE;

        for (i = 0; i < KNAV_DMA_FDQ_PER_CHAN; ++i) {
                if (netcp->rx_fdq[i])
                        last_fdq = knav_queue_get_id(netcp->rx_fdq[i]);
                config.u.rx.fdq[i] = last_fdq;
        }

        netcp->rx_channel = knav_dma_open_channel(netcp->netcp_device->device,
                                        netcp->dma_chan_name, &config);
        if (IS_ERR(netcp->rx_channel)) {
                dev_err(netcp->ndev_dev, "failed opening rx chan(%s\n",
                        netcp->dma_chan_name);
                ret = PTR_ERR(netcp->rx_channel);
                goto fail;
        }

        dev_dbg(netcp->ndev_dev, "opened RX channel: %p\n", netcp->rx_channel);
        return 0;

fail:
        netcp_free_navigator_resources(netcp);
        return ret;
}

/* Open the device */
static int netcp_ndo_open(struct net_device *ndev)
{
        struct netcp_intf *netcp = netdev_priv(ndev);
        struct netcp_intf_modpriv *intf_modpriv;
        struct netcp_module *module;
        int ret;

        netif_carrier_off(ndev);
        ret = netcp_setup_navigator_resources(ndev);
        if (ret) {
                dev_err(netcp->ndev_dev, "Failed to setup navigator resources\n");
                goto fail;
        }

        for_each_module(netcp, intf_modpriv) {
                module = intf_modpriv->netcp_module;
                if (module->open) {
                        ret = module->open(intf_modpriv->module_priv, ndev);
                        if (ret != 0) {
                                dev_err(netcp->ndev_dev, "module open failed\n");
                                goto fail_open;
                        }
                }
        }

        napi_enable(&netcp->rx_napi);
        napi_enable(&netcp->tx_napi);
        knav_queue_enable_notify(netcp->tx_compl_q);
        knav_queue_enable_notify(netcp->rx_queue);
        netcp_rxpool_refill(netcp);
        netif_tx_wake_all_queues(ndev);
        dev_dbg(netcp->ndev_dev, "netcp device %s opened\n", ndev->name);
        return 0;

fail_open:
        for_each_module(netcp, intf_modpriv) {
                module = intf_modpriv->netcp_module;
                if (module->close)
                        module->close(intf_modpriv->module_priv, ndev);
        }

fail:
        netcp_free_navigator_resources(netcp);
        return ret;
}

/* Close the device */
static int netcp_ndo_stop(struct net_device *ndev)
{
        struct netcp_intf *netcp = netdev_priv(ndev);
        struct netcp_intf_modpriv *intf_modpriv;
        struct netcp_module *module;
        int err = 0;

        netif_tx_stop_all_queues(ndev);
        netif_carrier_off(ndev);
        netcp_addr_clear_mark(netcp);
        netcp_addr_sweep_del(netcp);
        knav_queue_disable_notify(netcp->rx_queue);
        knav_queue_disable_notify(netcp->tx_compl_q);
        napi_disable(&netcp->rx_napi);
        napi_disable(&netcp->tx_napi);

        for_each_module(netcp, intf_modpriv) {
                module = intf_modpriv->netcp_module;
                if (module->close) {
                        err = module->close(intf_modpriv->module_priv, ndev);
                        if (err != 0)
                                dev_err(netcp->ndev_dev, "Close failed\n");
                }
        }

        /* Recycle Rx descriptors from completion queue */
        netcp_empty_rx_queue(netcp);

        /* Recycle Tx descriptors from completion queue */
        netcp_process_tx_compl_packets(netcp, netcp->tx_pool_size);

        if (knav_pool_count(netcp->tx_pool) != netcp->tx_pool_size)
                dev_err(netcp->ndev_dev, "Lost (%d) Tx descs\n",
                        netcp->tx_pool_size - knav_pool_count(netcp->tx_pool));

        netcp_free_navigator_resources(netcp);
        dev_dbg(netcp->ndev_dev, "netcp device %s stopped\n", ndev->name);
        return 0;
}

static int netcp_ndo_ioctl(struct net_device *ndev,
                           struct ifreq *req, int cmd)
{
        struct netcp_intf *netcp = netdev_priv(ndev);
        struct netcp_intf_modpriv *intf_modpriv;
        struct netcp_module *module;
        int ret = -1, err = -EOPNOTSUPP;

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

        for_each_module(netcp, intf_modpriv) {
                module = intf_modpriv->netcp_module;
                if (!module->ioctl)
                        continue;

                err = module->ioctl(intf_modpriv->module_priv, req, cmd);
                if ((err < 0) && (err != -EOPNOTSUPP)) {
                        ret = err;
                        goto out;
                }
                if (err == 0)
                        ret = err;
        }

out:
        return (ret == 0) ? 0 : err;
}

static void netcp_ndo_tx_timeout(struct net_device *ndev)
{
        struct netcp_intf *netcp = netdev_priv(ndev);
        unsigned int descs = knav_pool_count(netcp->tx_pool);

        dev_err(netcp->ndev_dev, "transmit timed out tx descs(%d)\n", descs);
        netcp_process_tx_compl_packets(netcp, netcp->tx_pool_size);
        netif_trans_update(ndev);
        netif_tx_wake_all_queues(ndev);
}

static int netcp_rx_add_vid(struct net_device *ndev, __be16 proto, u16 vid)
{
        struct netcp_intf *netcp = netdev_priv(ndev);
        struct netcp_intf_modpriv *intf_modpriv;
        struct netcp_module *module;
        unsigned long flags;
        int err = 0;

        dev_dbg(netcp->ndev_dev, "adding rx vlan id: %d\n", vid);

        spin_lock_irqsave(&netcp->lock, flags);
        for_each_module(netcp, intf_modpriv) {
                module = intf_modpriv->netcp_module;
                if ((module->add_vid) && (vid != 0)) {
                        err = module->add_vid(intf_modpriv->module_priv, vid);
                        if (err != 0) {
                                dev_err(netcp->ndev_dev, "Could not add vlan id = %d\n",
                                        vid);
                                break;
                        }
                }
        }
        spin_unlock_irqrestore(&netcp->lock, flags);

        return err;
}

static int netcp_rx_kill_vid(struct net_device *ndev, __be16 proto, u16 vid)
{
        struct netcp_intf *netcp = netdev_priv(ndev);
        struct netcp_intf_modpriv *intf_modpriv;
        struct netcp_module *module;
        unsigned long flags;
        int err = 0;

        dev_dbg(netcp->ndev_dev, "removing rx vlan id: %d\n", vid);

        spin_lock_irqsave(&netcp->lock, flags);
        for_each_module(netcp, intf_modpriv) {
                module = intf_modpriv->netcp_module;
                if (module->del_vid) {
                        err = module->del_vid(intf_modpriv->module_priv, vid);
                        if (err != 0) {
                                dev_err(netcp->ndev_dev, "Could not delete vlan id = %d\n",
                                        vid);
                                break;
                        }
                }
        }
        spin_unlock_irqrestore(&netcp->lock, flags);
        return err;
}

static u16 netcp_select_queue(struct net_device *dev, struct sk_buff *skb,
                              void *accel_priv,
                              select_queue_fallback_t fallback)
{
        return 0;
}

static int netcp_setup_tc(struct net_device *dev, enum tc_setup_type type,
                          void *type_data)
{
        struct tc_mqprio_qopt *mqprio = type_data;
        u8 num_tc;
        int i;

        /* setup tc must be called under rtnl lock */
        ASSERT_RTNL();

        if (type != TC_SETUP_QDISC_MQPRIO)
                return -EOPNOTSUPP;

        mqprio->hw = TC_MQPRIO_HW_OFFLOAD_TCS;
        num_tc = mqprio->num_tc;

        /* Sanity-check the number of traffic classes requested */
        if ((dev->real_num_tx_queues <= 1) ||
            (dev->real_num_tx_queues < num_tc))
                return -EINVAL;

        /* Configure traffic class to queue mappings */
        if (num_tc) {
                netdev_set_num_tc(dev, num_tc);
                for (i = 0; i < num_tc; i++)
                        netdev_set_tc_queue(dev, i, 1, i);
        } else {
                netdev_reset_tc(dev);
        }

        return 0;
}

static void
netcp_get_stats(struct net_device *ndev, struct rtnl_link_stats64 *stats)
{
        struct netcp_intf *netcp = netdev_priv(ndev);
        struct netcp_stats *p = &netcp->stats;
        u64 rxpackets, rxbytes, txpackets, txbytes;
        unsigned int start;

        do {
                start = u64_stats_fetch_begin_irq(&p->syncp_rx);
                rxpackets       = p->rx_packets;
                rxbytes         = p->rx_bytes;
        } while (u64_stats_fetch_retry_irq(&p->syncp_rx, start));

        do {
                start = u64_stats_fetch_begin_irq(&p->syncp_tx);
                txpackets       = p->tx_packets;
                txbytes         = p->tx_bytes;
        } while (u64_stats_fetch_retry_irq(&p->syncp_tx, start));

        stats->rx_packets = rxpackets;
        stats->rx_bytes = rxbytes;
        stats->tx_packets = txpackets;
        stats->tx_bytes = txbytes;

        /* The following are stored as 32 bit */
        stats->rx_errors = p->rx_errors;
        stats->rx_dropped = p->rx_dropped;
        stats->tx_dropped = p->tx_dropped;
}

static const struct net_device_ops netcp_netdev_ops = {
        .ndo_open               = netcp_ndo_open,
        .ndo_stop               = netcp_ndo_stop,
        .ndo_start_xmit         = netcp_ndo_start_xmit,
        .ndo_set_rx_mode        = netcp_set_rx_mode,
        .ndo_do_ioctl           = netcp_ndo_ioctl,
        .ndo_get_stats64        = netcp_get_stats,
        .ndo_set_mac_address    = eth_mac_addr,
        .ndo_validate_addr      = eth_validate_addr,
        .ndo_vlan_rx_add_vid    = netcp_rx_add_vid,
        .ndo_vlan_rx_kill_vid   = netcp_rx_kill_vid,
        .ndo_tx_timeout         = netcp_ndo_tx_timeout,
        .ndo_select_queue       = netcp_select_queue,
        .ndo_setup_tc           = netcp_setup_tc,
};

static int netcp_create_interface(struct netcp_device *netcp_device,
                                  struct device_node *node_interface)
{
        struct device *dev = netcp_device->device;
        struct device_node *node = dev->of_node;
        struct netcp_intf *netcp;
        struct net_device *ndev;
        resource_size_t size;
        struct resource res;
        void __iomem *efuse = NULL;
        u32 efuse_mac = 0;
        const void *mac_addr;
        u8 efuse_mac_addr[6];
        u32 temp[2];
        int ret = 0;

        ndev = alloc_etherdev_mqs(sizeof(*netcp), 1, 1);
        if (!ndev) {
                dev_err(dev, "Error allocating netdev\n");
                return -ENOMEM;
        }

        ndev->features |= NETIF_F_SG;
        ndev->features |= NETIF_F_HW_VLAN_CTAG_FILTER;
        ndev->hw_features = ndev->features;
        ndev->vlan_features |=  NETIF_F_SG;

        /* MTU range: 68 - 9486 */
        ndev->min_mtu = ETH_MIN_MTU;
        ndev->max_mtu = NETCP_MAX_FRAME_SIZE - (ETH_HLEN + ETH_FCS_LEN);

        netcp = netdev_priv(ndev);
        spin_lock_init(&netcp->lock);
        INIT_LIST_HEAD(&netcp->module_head);
        INIT_LIST_HEAD(&netcp->txhook_list_head);
        INIT_LIST_HEAD(&netcp->rxhook_list_head);
        INIT_LIST_HEAD(&netcp->addr_list);
        u64_stats_init(&netcp->stats.syncp_rx);
        u64_stats_init(&netcp->stats.syncp_tx);
        netcp->netcp_device = netcp_device;
        netcp->dev = netcp_device->device;

        netcp->ndev = ndev;
        netcp->ndev_dev  = &ndev->dev;
        netcp->msg_enable = netif_msg_init(netcp_debug_level, NETCP_DEBUG);
        netcp->tx_pause_threshold = MAX_SKB_FRAGS;
        netcp->tx_resume_threshold = netcp->tx_pause_threshold;
        netcp->node_interface = node_interface;

        ret = of_property_read_u32(node_interface, "efuse-mac", &efuse_mac);
        if (efuse_mac) {
                if (of_address_to_resource(node, NETCP_EFUSE_REG_INDEX, &res)) {
                        dev_err(dev, "could not find efuse-mac reg resource\n");
                        ret = -ENODEV;
                        goto quit;
                }
                size = resource_size(&res);

                if (!devm_request_mem_region(dev, res.start, size,
                                             dev_name(dev))) {
                        dev_err(dev, "could not reserve resource\n");
                        ret = -ENOMEM;
                        goto quit;
                }

                efuse = devm_ioremap_nocache(dev, res.start, size);
                if (!efuse) {
                        dev_err(dev, "could not map resource\n");
                        devm_release_mem_region(dev, res.start, size);
                        ret = -ENOMEM;
                        goto quit;
                }

                emac_arch_get_mac_addr(efuse_mac_addr, efuse, efuse_mac);
                if (is_valid_ether_addr(efuse_mac_addr))
                        ether_addr_copy(ndev->dev_addr, efuse_mac_addr);
                else
                        random_ether_addr(ndev->dev_addr);

                devm_iounmap(dev, efuse);
                devm_release_mem_region(dev, res.start, size);
        } else {
                mac_addr = of_get_mac_address(node_interface);
                if (mac_addr)
                        ether_addr_copy(ndev->dev_addr, mac_addr);
                else
                        random_ether_addr(ndev->dev_addr);
        }

        ret = of_property_read_string(node_interface, "rx-channel",
                                      &netcp->dma_chan_name);
        if (ret < 0) {
                dev_err(dev, "missing \"rx-channel\" parameter\n");
                ret = -ENODEV;
                goto quit;
        }

        ret = of_property_read_u32(node_interface, "rx-queue",
                                   &netcp->rx_queue_id);
        if (ret < 0) {
                dev_warn(dev, "missing \"rx-queue\" parameter\n");
                netcp->rx_queue_id = KNAV_QUEUE_QPEND;
        }

        ret = of_property_read_u32_array(node_interface, "rx-queue-depth",
                                         netcp->rx_queue_depths,
                                         KNAV_DMA_FDQ_PER_CHAN);
        if (ret < 0) {
                dev_err(dev, "missing \"rx-queue-depth\" parameter\n");
                netcp->rx_queue_depths[0] = 128;
        }

        ret = of_property_read_u32_array(node_interface, "rx-pool", temp, 2);
        if (ret < 0) {
                dev_err(dev, "missing \"rx-pool\" parameter\n");
                ret = -ENODEV;
                goto quit;
        }
        netcp->rx_pool_size = temp[0];
        netcp->rx_pool_region_id = temp[1];

        ret = of_property_read_u32_array(node_interface, "tx-pool", temp, 2);
        if (ret < 0) {
                dev_err(dev, "missing \"tx-pool\" parameter\n");
                ret = -ENODEV;
                goto quit;
        }
        netcp->tx_pool_size = temp[0];
        netcp->tx_pool_region_id = temp[1];

        if (netcp->tx_pool_size < MAX_SKB_FRAGS) {
                dev_err(dev, "tx-pool size too small, must be atleast(%ld)\n",
                        MAX_SKB_FRAGS);
                ret = -ENODEV;
                goto quit;
        }

        ret = of_property_read_u32(node_interface, "tx-completion-queue",
                                   &netcp->tx_compl_qid);
        if (ret < 0) {
                dev_warn(dev, "missing \"tx-completion-queue\" parameter\n");
                netcp->tx_compl_qid = KNAV_QUEUE_QPEND;
        }

        /* NAPI register */
        netif_napi_add(ndev, &netcp->rx_napi, netcp_rx_poll, NETCP_NAPI_WEIGHT);
        netif_tx_napi_add(ndev, &netcp->tx_napi, netcp_tx_poll, NETCP_NAPI_WEIGHT);

        /* Register the network device */
        ndev->dev_id            = 0;
        ndev->watchdog_timeo    = NETCP_TX_TIMEOUT;
        ndev->netdev_ops        = &netcp_netdev_ops;
        SET_NETDEV_DEV(ndev, dev);

        list_add_tail(&netcp->interface_list, &netcp_device->interface_head);
        return 0;

quit:
        free_netdev(ndev);
        return ret;
}

static void netcp_delete_interface(struct netcp_device *netcp_device,
                                   struct net_device *ndev)
{
        struct netcp_intf_modpriv *intf_modpriv, *tmp;
        struct netcp_intf *netcp = netdev_priv(ndev);
        struct netcp_module *module;

        dev_dbg(netcp_device->device, "Removing interface \"%s\"\n",
                ndev->name);

        /* Notify each of the modules that the interface is going away */
        list_for_each_entry_safe(intf_modpriv, tmp, &netcp->module_head,
                                 intf_list) {
                module = intf_modpriv->netcp_module;
                dev_dbg(netcp_device->device, "Releasing module \"%s\"\n",
                        module->name);
                if (module->release)
                        module->release(intf_modpriv->module_priv);
                list_del(&intf_modpriv->intf_list);
        }
        WARN(!list_empty(&netcp->module_head), "%s interface module list is not empty!\n",
             ndev->name);

        list_del(&netcp->interface_list);

        of_node_put(netcp->node_interface);
        unregister_netdev(ndev);
        free_netdev(ndev);
}

static int netcp_probe(struct platform_device *pdev)
{
        struct device_node *node = pdev->dev.of_node;
        struct netcp_intf *netcp_intf, *netcp_tmp;
        struct device_node *child, *interfaces;
        struct netcp_device *netcp_device;
        struct device *dev = &pdev->dev;
        int ret;

        if (!node) {
                dev_err(dev, "could not find device info\n");
                return -ENODEV;
        }

        /* Allocate a new NETCP device instance */
        netcp_device = devm_kzalloc(dev, sizeof(*netcp_device), GFP_KERNEL);
        if (!netcp_device)
                return -ENOMEM;

        pm_runtime_enable(&pdev->dev);
        ret = pm_runtime_get_sync(&pdev->dev);
        if (ret < 0) {
                dev_err(dev, "Failed to enable NETCP power-domain\n");
                pm_runtime_disable(&pdev->dev);
                return ret;
        }

        /* Initialize the NETCP device instance */
        INIT_LIST_HEAD(&netcp_device->interface_head);
        INIT_LIST_HEAD(&netcp_device->modpriv_head);
        netcp_device->device = dev;
        platform_set_drvdata(pdev, netcp_device);

        /* create interfaces */
        interfaces = of_get_child_by_name(node, "netcp-interfaces");
        if (!interfaces) {
                dev_err(dev, "could not find netcp-interfaces node\n");
                ret = -ENODEV;
                goto probe_quit;
        }

        for_each_available_child_of_node(interfaces, child) {
                ret = netcp_create_interface(netcp_device, child);
                if (ret) {
                        dev_err(dev, "could not create interface(%s)\n",
                                child->name);
                        goto probe_quit_interface;
                }
        }

        of_node_put(interfaces);

        /* Add the device instance to the list */
        list_add_tail(&netcp_device->device_list, &netcp_devices);

        return 0;

probe_quit_interface:
        list_for_each_entry_safe(netcp_intf, netcp_tmp,
                                 &netcp_device->interface_head,
                                 interface_list) {
                netcp_delete_interface(netcp_device, netcp_intf->ndev);
        }

        of_node_put(interfaces);

probe_quit:
        pm_runtime_put_sync(&pdev->dev);
        pm_runtime_disable(&pdev->dev);
        platform_set_drvdata(pdev, NULL);
        return ret;
}

static int netcp_remove(struct platform_device *pdev)
{
        struct netcp_device *netcp_device = platform_get_drvdata(pdev);
        struct netcp_intf *netcp_intf, *netcp_tmp;
        struct netcp_inst_modpriv *inst_modpriv, *tmp;
        struct netcp_module *module;

        list_for_each_entry_safe(inst_modpriv, tmp, &netcp_device->modpriv_head,
                                 inst_list) {
                module = inst_modpriv->netcp_module;
                dev_dbg(&pdev->dev, "Removing module \"%s\"\n", module->name);
                module->remove(netcp_device, inst_modpriv->module_priv);
                list_del(&inst_modpriv->inst_list);
        }

        /* now that all modules are removed, clean up the interfaces */
        list_for_each_entry_safe(netcp_intf, netcp_tmp,
                                 &netcp_device->interface_head,
                                 interface_list) {
                netcp_delete_interface(netcp_device, netcp_intf->ndev);
        }

        WARN(!list_empty(&netcp_device->interface_head),
             "%s interface list not empty!\n", pdev->name);

        pm_runtime_put_sync(&pdev->dev);
        pm_runtime_disable(&pdev->dev);
        platform_set_drvdata(pdev, NULL);
        return 0;
}

static const struct of_device_id of_match[] = {
        { .compatible = "ti,netcp-1.0", },
        {},
};
MODULE_DEVICE_TABLE(of, of_match);

static struct platform_driver netcp_driver = {
        .driver = {
                .name           = "netcp-1.0",
                .of_match_table = of_match,
        },
        .probe = netcp_probe,
        .remove = netcp_remove,
};
module_platform_driver(netcp_driver);

MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("TI NETCP driver for Keystone SOCs");
MODULE_AUTHOR("Sandeep Nair <sandeep_n@ti.com");