// SPDX-License-Identifier: GPL-2.0
/* Marvell Octeon EP (EndPoint) Ethernet Driver
 *
 * Copyright (C) 2020 Marvell.
 *
 */

#include <linux/types.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/rtnetlink.h>
#include <linux/vmalloc.h>

#include "octep_config.h"
#include "octep_main.h"
#include "octep_ctrl_net.h"
#include "octep_pfvf_mbox.h"

#define OCTEP_INTR_POLL_TIME_MSECS    100
struct workqueue_struct *octep_wq;

/* Supported Devices */
static const struct pci_device_id octep_pci_id_tbl[] = {
        {PCI_DEVICE(PCI_VENDOR_ID_CAVIUM, OCTEP_PCI_DEVICE_ID_CN98_PF)},
        {PCI_DEVICE(PCI_VENDOR_ID_CAVIUM, OCTEP_PCI_DEVICE_ID_CN93_PF)},
        {PCI_DEVICE(PCI_VENDOR_ID_CAVIUM, OCTEP_PCI_DEVICE_ID_CNF95N_PF)},
        {PCI_DEVICE(PCI_VENDOR_ID_CAVIUM, OCTEP_PCI_DEVICE_ID_CN10KA_PF)},
        {PCI_DEVICE(PCI_VENDOR_ID_CAVIUM, OCTEP_PCI_DEVICE_ID_CNF10KA_PF)},
        {PCI_DEVICE(PCI_VENDOR_ID_CAVIUM, OCTEP_PCI_DEVICE_ID_CNF10KB_PF)},
        {PCI_DEVICE(PCI_VENDOR_ID_CAVIUM, OCTEP_PCI_DEVICE_ID_CN10KB_PF)},
        {0, },
};
MODULE_DEVICE_TABLE(pci, octep_pci_id_tbl);

MODULE_AUTHOR("Veerasenareddy Burru <vburru@marvell.com>");
MODULE_DESCRIPTION(OCTEP_DRV_STRING);
MODULE_LICENSE("GPL");

/**
 * octep_alloc_ioq_vectors() - Allocate Tx/Rx Queue interrupt info.
 *
 * @oct: Octeon device private data structure.
 *
 * Allocate resources to hold per Tx/Rx queue interrupt info.
 * This is the information passed to interrupt handler, from which napi poll
 * is scheduled and includes quick access to private data of Tx/Rx queue
 * corresponding to the interrupt being handled.
 *
 * Return: 0, on successful allocation of resources for all queue interrupts.
 *         -1, if failed to allocate any resource.
 */
static int octep_alloc_ioq_vectors(struct octep_device *oct)
{
        int i;
        struct octep_ioq_vector *ioq_vector;

        for (i = 0; i < oct->num_oqs; i++) {
                oct->ioq_vector[i] = vzalloc(sizeof(*oct->ioq_vector[i]));
                if (!oct->ioq_vector[i])
                        goto free_ioq_vector;

                ioq_vector = oct->ioq_vector[i];
                ioq_vector->iq = oct->iq[i];
                ioq_vector->oq = oct->oq[i];
                ioq_vector->octep_dev = oct;
        }

        dev_info(&oct->pdev->dev, "Allocated %d IOQ vectors\n", oct->num_oqs);
        return 0;

free_ioq_vector:
        while (i) {
                i--;
                vfree(oct->ioq_vector[i]);
                oct->ioq_vector[i] = NULL;
        }
        return -1;
}

/**
 * octep_free_ioq_vectors() - Free Tx/Rx Queue interrupt vector info.
 *
 * @oct: Octeon device private data structure.
 */
static void octep_free_ioq_vectors(struct octep_device *oct)
{
        int i;

        for (i = 0; i < oct->num_oqs; i++) {
                if (oct->ioq_vector[i]) {
                        vfree(oct->ioq_vector[i]);
                        oct->ioq_vector[i] = NULL;
                }
        }
        netdev_info(oct->netdev, "Freed IOQ Vectors\n");
}

/**
 * octep_enable_msix_range() - enable MSI-x interrupts.
 *
 * @oct: Octeon device private data structure.
 *
 * Allocate and enable all MSI-x interrupts (queue and non-queue interrupts)
 * for the Octeon device.
 *
 * Return: 0, on successfully enabling all MSI-x interrupts.
 *         -1, if failed to enable any MSI-x interrupt.
 */
static int octep_enable_msix_range(struct octep_device *oct)
{
        int num_msix, msix_allocated;
        int i;

        /* Generic interrupts apart from input/output queues */
        num_msix = oct->num_oqs + CFG_GET_NON_IOQ_MSIX(oct->conf);
        oct->msix_entries = kzalloc_objs(struct msix_entry, num_msix);
        if (!oct->msix_entries)
                goto msix_alloc_err;

        for (i = 0; i < num_msix; i++)
                oct->msix_entries[i].entry = i;

        msix_allocated = pci_enable_msix_range(oct->pdev, oct->msix_entries,
                                               num_msix, num_msix);
        if (msix_allocated != num_msix) {
                dev_err(&oct->pdev->dev,
                        "Failed to enable %d msix irqs; got only %d\n",
                        num_msix, msix_allocated);
                goto enable_msix_err;
        }
        oct->num_irqs = msix_allocated;
        dev_info(&oct->pdev->dev, "MSI-X enabled successfully\n");

        return 0;

enable_msix_err:
        if (msix_allocated > 0)
                pci_disable_msix(oct->pdev);
        kfree(oct->msix_entries);
        oct->msix_entries = NULL;
msix_alloc_err:
        return -1;
}

/**
 * octep_disable_msix() - disable MSI-x interrupts.
 *
 * @oct: Octeon device private data structure.
 *
 * Disable MSI-x on the Octeon device.
 */
static void octep_disable_msix(struct octep_device *oct)
{
        pci_disable_msix(oct->pdev);
        kfree(oct->msix_entries);
        oct->msix_entries = NULL;
        dev_info(&oct->pdev->dev, "Disabled MSI-X\n");
}

/**
 * octep_mbox_intr_handler() - common handler for pfvf mbox interrupts.
 *
 * @irq: Interrupt number.
 * @data: interrupt data.
 *
 * this is common handler for pfvf mbox interrupts.
 */
static irqreturn_t octep_mbox_intr_handler(int irq, void *data)
{
        struct octep_device *oct = data;

        return oct->hw_ops.mbox_intr_handler(oct);
}

/**
 * octep_oei_intr_handler() - common handler for output endpoint interrupts.
 *
 * @irq: Interrupt number.
 * @data: interrupt data.
 *
 * this is common handler for all output endpoint interrupts.
 */
static irqreturn_t octep_oei_intr_handler(int irq, void *data)
{
        struct octep_device *oct = data;

        return oct->hw_ops.oei_intr_handler(oct);
}

/**
 * octep_ire_intr_handler() - common handler for input ring error interrupts.
 *
 * @irq: Interrupt number.
 * @data: interrupt data.
 *
 * this is common handler for input ring error interrupts.
 */
static irqreturn_t octep_ire_intr_handler(int irq, void *data)
{
        struct octep_device *oct = data;

        return oct->hw_ops.ire_intr_handler(oct);
}

/**
 * octep_ore_intr_handler() - common handler for output ring error interrupts.
 *
 * @irq: Interrupt number.
 * @data: interrupt data.
 *
 * this is common handler for output ring error interrupts.
 */
static irqreturn_t octep_ore_intr_handler(int irq, void *data)
{
        struct octep_device *oct = data;

        return oct->hw_ops.ore_intr_handler(oct);
}

/**
 * octep_vfire_intr_handler() - common handler for vf input ring error interrupts.
 *
 * @irq: Interrupt number.
 * @data: interrupt data.
 *
 * this is common handler for vf input ring error interrupts.
 */
static irqreturn_t octep_vfire_intr_handler(int irq, void *data)
{
        struct octep_device *oct = data;

        return oct->hw_ops.vfire_intr_handler(oct);
}

/**
 * octep_vfore_intr_handler() - common handler for vf output ring error interrupts.
 *
 * @irq: Interrupt number.
 * @data: interrupt data.
 *
 * this is common handler for vf output ring error interrupts.
 */
static irqreturn_t octep_vfore_intr_handler(int irq, void *data)
{
        struct octep_device *oct = data;

        return oct->hw_ops.vfore_intr_handler(oct);
}

/**
 * octep_dma_intr_handler() - common handler for dpi dma related interrupts.
 *
 * @irq: Interrupt number.
 * @data: interrupt data.
 *
 * this is common handler for dpi dma related interrupts.
 */
static irqreturn_t octep_dma_intr_handler(int irq, void *data)
{
        struct octep_device *oct = data;

        return oct->hw_ops.dma_intr_handler(oct);
}

/**
 * octep_dma_vf_intr_handler() - common handler for dpi dma transaction error interrupts for VFs.
 *
 * @irq: Interrupt number.
 * @data: interrupt data.
 *
 * this is common handler for dpi dma transaction error interrupts for VFs.
 */
static irqreturn_t octep_dma_vf_intr_handler(int irq, void *data)
{
        struct octep_device *oct = data;

        return oct->hw_ops.dma_vf_intr_handler(oct);
}

/**
 * octep_pp_vf_intr_handler() - common handler for pp transaction error interrupts for VFs.
 *
 * @irq: Interrupt number.
 * @data: interrupt data.
 *
 * this is common handler for pp transaction error interrupts for VFs.
 */
static irqreturn_t octep_pp_vf_intr_handler(int irq, void *data)
{
        struct octep_device *oct = data;

        return oct->hw_ops.pp_vf_intr_handler(oct);
}

/**
 * octep_misc_intr_handler() - common handler for mac related interrupts.
 *
 * @irq: Interrupt number.
 * @data: interrupt data.
 *
 * this is common handler for mac related interrupts.
 */
static irqreturn_t octep_misc_intr_handler(int irq, void *data)
{
        struct octep_device *oct = data;

        return oct->hw_ops.misc_intr_handler(oct);
}

/**
 * octep_rsvd_intr_handler() - common handler for reserved interrupts (future use).
 *
 * @irq: Interrupt number.
 * @data: interrupt data.
 *
 * this is common handler for all reserved interrupts.
 */
static irqreturn_t octep_rsvd_intr_handler(int irq, void *data)
{
        struct octep_device *oct = data;

        return oct->hw_ops.rsvd_intr_handler(oct);
}

/**
 * octep_ioq_intr_handler() - handler for all Tx/Rx queue interrupts.
 *
 * @irq: Interrupt number.
 * @data: interrupt data contains pointers to Tx/Rx queue private data
 *         and correspong NAPI context.
 *
 * this is common handler for all non-queue (generic) interrupts.
 */
static irqreturn_t octep_ioq_intr_handler(int irq, void *data)
{
        struct octep_ioq_vector *ioq_vector = data;
        struct octep_device *oct = ioq_vector->octep_dev;

        return oct->hw_ops.ioq_intr_handler(ioq_vector);
}

/**
 * octep_request_irqs() - Register interrupt handlers.
 *
 * @oct: Octeon device private data structure.
 *
 * Register handlers for all queue and non-queue interrupts.
 *
 * Return: 0, on successful registration of all interrupt handlers.
 *         -1, on any error.
 */
static int octep_request_irqs(struct octep_device *oct)
{
        struct net_device *netdev = oct->netdev;
        struct octep_ioq_vector *ioq_vector;
        struct msix_entry *msix_entry;
        char **non_ioq_msix_names;
        int num_non_ioq_msix;
        int ret, i, j;

        num_non_ioq_msix = CFG_GET_NON_IOQ_MSIX(oct->conf);
        non_ioq_msix_names = CFG_GET_NON_IOQ_MSIX_NAMES(oct->conf);

        oct->non_ioq_irq_names = kcalloc(num_non_ioq_msix,
                                         OCTEP_MSIX_NAME_SIZE, GFP_KERNEL);
        if (!oct->non_ioq_irq_names)
                goto alloc_err;

        /* First few MSI-X interrupts are non-queue interrupts */
        for (i = 0; i < num_non_ioq_msix; i++) {
                char *irq_name;

                irq_name = &oct->non_ioq_irq_names[i * OCTEP_MSIX_NAME_SIZE];
                msix_entry = &oct->msix_entries[i];

                snprintf(irq_name, OCTEP_MSIX_NAME_SIZE,
                         "%s-%s", netdev->name, non_ioq_msix_names[i]);
                if (!strncmp(non_ioq_msix_names[i], "epf_mbox_rint", strlen("epf_mbox_rint"))) {
                        ret = request_irq(msix_entry->vector,
                                          octep_mbox_intr_handler, 0,
                                          irq_name, oct);
                } else if (!strncmp(non_ioq_msix_names[i], "epf_oei_rint",
                           strlen("epf_oei_rint"))) {
                        ret = request_irq(msix_entry->vector,
                                          octep_oei_intr_handler, 0,
                                          irq_name, oct);
                } else if (!strncmp(non_ioq_msix_names[i], "epf_ire_rint",
                           strlen("epf_ire_rint"))) {
                        ret = request_irq(msix_entry->vector,
                                          octep_ire_intr_handler, 0,
                                          irq_name, oct);
                } else if (!strncmp(non_ioq_msix_names[i], "epf_ore_rint",
                           strlen("epf_ore_rint"))) {
                        ret = request_irq(msix_entry->vector,
                                          octep_ore_intr_handler, 0,
                                          irq_name, oct);
                } else if (!strncmp(non_ioq_msix_names[i], "epf_vfire_rint",
                           strlen("epf_vfire_rint"))) {
                        ret = request_irq(msix_entry->vector,
                                          octep_vfire_intr_handler, 0,
                                          irq_name, oct);
                } else if (!strncmp(non_ioq_msix_names[i], "epf_vfore_rint",
                           strlen("epf_vfore_rint"))) {
                        ret = request_irq(msix_entry->vector,
                                          octep_vfore_intr_handler, 0,
                                          irq_name, oct);
                } else if (!strncmp(non_ioq_msix_names[i], "epf_dma_rint",
                           strlen("epf_dma_rint"))) {
                        ret = request_irq(msix_entry->vector,
                                          octep_dma_intr_handler, 0,
                                          irq_name, oct);
                } else if (!strncmp(non_ioq_msix_names[i], "epf_dma_vf_rint",
                           strlen("epf_dma_vf_rint"))) {
                        ret = request_irq(msix_entry->vector,
                                          octep_dma_vf_intr_handler, 0,
                                          irq_name, oct);
                } else if (!strncmp(non_ioq_msix_names[i], "epf_pp_vf_rint",
                           strlen("epf_pp_vf_rint"))) {
                        ret = request_irq(msix_entry->vector,
                                          octep_pp_vf_intr_handler, 0,
                                          irq_name, oct);
                } else if (!strncmp(non_ioq_msix_names[i], "epf_misc_rint",
                           strlen("epf_misc_rint"))) {
                        ret = request_irq(msix_entry->vector,
                                          octep_misc_intr_handler, 0,
                                          irq_name, oct);
                } else {
                        ret = request_irq(msix_entry->vector,
                                          octep_rsvd_intr_handler, 0,
                                          irq_name, oct);
                }

                if (ret) {
                        netdev_err(netdev,
                                   "request_irq failed for %s; err=%d",
                                   irq_name, ret);
                        goto non_ioq_irq_err;
                }
        }

        /* Request IRQs for Tx/Rx queues */
        for (j = 0; j < oct->num_oqs; j++) {
                ioq_vector = oct->ioq_vector[j];
                msix_entry = &oct->msix_entries[j + num_non_ioq_msix];

                snprintf(ioq_vector->name, sizeof(ioq_vector->name),
                         "%s-q%d", netdev->name, j);
                ret = request_irq(msix_entry->vector,
                                  octep_ioq_intr_handler, 0,
                                  ioq_vector->name, ioq_vector);
                if (ret) {
                        netdev_err(netdev,
                                   "request_irq failed for Q-%d; err=%d",
                                   j, ret);
                        goto ioq_irq_err;
                }

                cpumask_set_cpu(j % num_online_cpus(),
                                &ioq_vector->affinity_mask);
                irq_set_affinity_hint(msix_entry->vector,
                                      &ioq_vector->affinity_mask);
        }

        return 0;
ioq_irq_err:
        while (j) {
                --j;
                ioq_vector = oct->ioq_vector[j];
                msix_entry = &oct->msix_entries[j + num_non_ioq_msix];

                irq_set_affinity_hint(msix_entry->vector, NULL);
                free_irq(msix_entry->vector, ioq_vector);
        }
non_ioq_irq_err:
        while (i) {
                --i;
                free_irq(oct->msix_entries[i].vector, oct);
        }
        kfree(oct->non_ioq_irq_names);
        oct->non_ioq_irq_names = NULL;
alloc_err:
        return -1;
}

/**
 * octep_free_irqs() - free all registered interrupts.
 *
 * @oct: Octeon device private data structure.
 *
 * Free all queue and non-queue interrupts of the Octeon device.
 */
static void octep_free_irqs(struct octep_device *oct)
{
        int i;

        /* First few MSI-X interrupts are non queue interrupts; free them */
        for (i = 0; i < CFG_GET_NON_IOQ_MSIX(oct->conf); i++)
                free_irq(oct->msix_entries[i].vector, oct);
        kfree(oct->non_ioq_irq_names);

        /* Free IRQs for Input/Output (Tx/Rx) queues */
        for (i = CFG_GET_NON_IOQ_MSIX(oct->conf); i < oct->num_irqs; i++) {
                irq_set_affinity_hint(oct->msix_entries[i].vector, NULL);
                free_irq(oct->msix_entries[i].vector,
                         oct->ioq_vector[i - CFG_GET_NON_IOQ_MSIX(oct->conf)]);
        }
        netdev_info(oct->netdev, "IRQs freed\n");
}

/**
 * octep_setup_irqs() - setup interrupts for the Octeon device.
 *
 * @oct: Octeon device private data structure.
 *
 * Allocate data structures to hold per interrupt information, allocate/enable
 * MSI-x interrupt and register interrupt handlers.
 *
 * Return: 0, on successful allocation and registration of all interrupts.
 *         -1, on any error.
 */
static int octep_setup_irqs(struct octep_device *oct)
{
        if (octep_alloc_ioq_vectors(oct))
                goto ioq_vector_err;

        if (octep_enable_msix_range(oct))
                goto enable_msix_err;

        if (octep_request_irqs(oct))
                goto request_irq_err;

        return 0;

request_irq_err:
        octep_disable_msix(oct);
enable_msix_err:
        octep_free_ioq_vectors(oct);
ioq_vector_err:
        return -1;
}

/**
 * octep_clean_irqs() - free all interrupts and its resources.
 *
 * @oct: Octeon device private data structure.
 */
static void octep_clean_irqs(struct octep_device *oct)
{
        octep_free_irqs(oct);
        octep_disable_msix(oct);
        octep_free_ioq_vectors(oct);
}

/**
 * octep_update_pkt() - Update IQ/OQ IN/OUT_CNT registers.
 *
 * @iq: Octeon Tx queue data structure.
 * @oq: Octeon Rx queue data structure.
 */
static void octep_update_pkt(struct octep_iq *iq, struct octep_oq *oq)
{
        u32 pkts_pend = READ_ONCE(oq->pkts_pending);
        u32 last_pkt_count = READ_ONCE(oq->last_pkt_count);
        u32 pkts_processed = READ_ONCE(iq->pkts_processed);
        u32 pkt_in_done = READ_ONCE(iq->pkt_in_done);

        netdev_dbg(iq->netdev, "enabling intr for Q-%u\n", iq->q_no);
        if (pkts_processed) {
                writel(pkts_processed, iq->inst_cnt_reg);
                readl(iq->inst_cnt_reg);
                WRITE_ONCE(iq->pkt_in_done, (pkt_in_done - pkts_processed));
                WRITE_ONCE(iq->pkts_processed, 0);
        }
        if (last_pkt_count - pkts_pend) {
                writel(last_pkt_count - pkts_pend, oq->pkts_sent_reg);
                readl(oq->pkts_sent_reg);
                WRITE_ONCE(oq->last_pkt_count, pkts_pend);
        }

        /* Flush the previous wrties before writing to RESEND bit */
        smp_wmb();
}

/**
 * octep_enable_ioq_irq() - Enable MSI-x interrupt of a Tx/Rx queue.
 *
 * @iq: Octeon Tx queue data structure.
 * @oq: Octeon Rx queue data structure.
 */
static void octep_enable_ioq_irq(struct octep_iq *iq, struct octep_oq *oq)
{
        writeq(1UL << OCTEP_OQ_INTR_RESEND_BIT, oq->pkts_sent_reg);
        writeq(1UL << OCTEP_IQ_INTR_RESEND_BIT, iq->inst_cnt_reg);
}

/**
 * octep_napi_poll() - NAPI poll function for Tx/Rx.
 *
 * @napi: pointer to napi context.
 * @budget: max number of packets to be processed in single invocation.
 */
static int octep_napi_poll(struct napi_struct *napi, int budget)
{
        struct octep_ioq_vector *ioq_vector =
                container_of(napi, struct octep_ioq_vector, napi);
        u32 tx_pending, rx_done;

        tx_pending = octep_iq_process_completions(ioq_vector->iq, budget);
        rx_done = octep_oq_process_rx(ioq_vector->oq, budget);

        /* need more polling if tx completion processing is still pending or
         * processed at least 'budget' number of rx packets.
         */
        if (tx_pending || rx_done >= budget)
                return budget;

        octep_update_pkt(ioq_vector->iq, ioq_vector->oq);
        napi_complete_done(napi, rx_done);
        octep_enable_ioq_irq(ioq_vector->iq, ioq_vector->oq);
        return rx_done;
}

/**
 * octep_napi_add() - Add NAPI poll for all Tx/Rx queues.
 *
 * @oct: Octeon device private data structure.
 */
static void octep_napi_add(struct octep_device *oct)
{
        int i;

        for (i = 0; i < oct->num_oqs; i++) {
                netdev_dbg(oct->netdev, "Adding NAPI on Q-%d\n", i);
                netif_napi_add(oct->netdev, &oct->ioq_vector[i]->napi,
                               octep_napi_poll);
                oct->oq[i]->napi = &oct->ioq_vector[i]->napi;
        }
}

/**
 * octep_napi_delete() - delete NAPI poll callback for all Tx/Rx queues.
 *
 * @oct: Octeon device private data structure.
 */
static void octep_napi_delete(struct octep_device *oct)
{
        int i;

        for (i = 0; i < oct->num_oqs; i++) {
                netdev_dbg(oct->netdev, "Deleting NAPI on Q-%d\n", i);
                netif_napi_del(&oct->ioq_vector[i]->napi);
                oct->oq[i]->napi = NULL;
        }
}

/**
 * octep_napi_enable() - enable NAPI for all Tx/Rx queues.
 *
 * @oct: Octeon device private data structure.
 */
static void octep_napi_enable(struct octep_device *oct)
{
        int i;

        for (i = 0; i < oct->num_oqs; i++) {
                netdev_dbg(oct->netdev, "Enabling NAPI on Q-%d\n", i);
                napi_enable(&oct->ioq_vector[i]->napi);
        }
}

/**
 * octep_napi_disable() - disable NAPI for all Tx/Rx queues.
 *
 * @oct: Octeon device private data structure.
 */
static void octep_napi_disable(struct octep_device *oct)
{
        int i;

        for (i = 0; i < oct->num_oqs; i++) {
                netdev_dbg(oct->netdev, "Disabling NAPI on Q-%d\n", i);
                napi_disable(&oct->ioq_vector[i]->napi);
        }
}

static void octep_link_up(struct net_device *netdev)
{
        netif_carrier_on(netdev);
        netif_tx_start_all_queues(netdev);
}

/**
 * octep_open() - start the octeon network device.
 *
 * @netdev: pointer to kernel network device.
 *
 * setup Tx/Rx queues, interrupts and enable hardware operation of Tx/Rx queues
 * and interrupts..
 *
 * Return: 0, on successfully setting up device and bring it up.
 *         -1, on any error.
 */
static int octep_open(struct net_device *netdev)
{
        struct octep_device *oct = netdev_priv(netdev);
        int err, ret;

        netdev_info(netdev, "Starting netdev ...\n");
        netif_carrier_off(netdev);

        oct->hw_ops.reset_io_queues(oct);

        if (octep_setup_iqs(oct))
                goto setup_iq_err;
        if (octep_setup_oqs(oct))
                goto setup_oq_err;
        if (octep_setup_irqs(oct))
                goto setup_irq_err;

        err = netif_set_real_num_tx_queues(netdev, oct->num_oqs);
        if (err)
                goto set_queues_err;
        err = netif_set_real_num_rx_queues(netdev, oct->num_iqs);
        if (err)
                goto set_queues_err;

        octep_napi_add(oct);
        octep_napi_enable(oct);

        oct->link_info.admin_up = 1;
        octep_ctrl_net_set_rx_state(oct, OCTEP_CTRL_NET_INVALID_VFID, true,
                                    false);
        octep_ctrl_net_set_link_status(oct, OCTEP_CTRL_NET_INVALID_VFID, true,
                                       false);
        oct->poll_non_ioq_intr = false;

        /* Enable the input and output queues for this Octeon device */
        oct->hw_ops.enable_io_queues(oct);

        /* Enable Octeon device interrupts */
        oct->hw_ops.enable_interrupts(oct);

        octep_oq_dbell_init(oct);

        ret = octep_ctrl_net_get_link_status(oct, OCTEP_CTRL_NET_INVALID_VFID);
        if (ret > 0)
                octep_link_up(netdev);

        return 0;

set_queues_err:
        octep_clean_irqs(oct);
setup_irq_err:
        octep_free_oqs(oct);
setup_oq_err:
        octep_free_iqs(oct);
setup_iq_err:
        return -1;
}

/**
 * octep_stop() - stop the octeon network device.
 *
 * @netdev: pointer to kernel network device.
 *
 * stop the device Tx/Rx operations, bring down the link and
 * free up all resources allocated for Tx/Rx queues and interrupts.
 */
static int octep_stop(struct net_device *netdev)
{
        struct octep_device *oct = netdev_priv(netdev);

        netdev_info(netdev, "Stopping the device ...\n");

        octep_ctrl_net_set_link_status(oct, OCTEP_CTRL_NET_INVALID_VFID, false,
                                       false);
        octep_ctrl_net_set_rx_state(oct, OCTEP_CTRL_NET_INVALID_VFID, false,
                                    false);

        /* Stop Tx from stack */
        netif_tx_stop_all_queues(netdev);
        netif_carrier_off(netdev);
        netif_tx_disable(netdev);

        oct->link_info.admin_up = 0;
        oct->link_info.oper_up = 0;

        oct->hw_ops.disable_interrupts(oct);
        octep_napi_disable(oct);
        octep_napi_delete(oct);

        octep_clean_irqs(oct);
        octep_clean_iqs(oct);

        oct->hw_ops.disable_io_queues(oct);
        oct->hw_ops.reset_io_queues(oct);
        octep_free_oqs(oct);
        octep_free_iqs(oct);

        oct->poll_non_ioq_intr = true;
        queue_delayed_work(octep_wq, &oct->intr_poll_task,
                           msecs_to_jiffies(OCTEP_INTR_POLL_TIME_MSECS));

        netdev_info(netdev, "Device stopped !!\n");
        return 0;
}

/**
 * octep_iq_full_check() - check if a Tx queue is full.
 *
 * @iq: Octeon Tx queue data structure.
 *
 * Return: 0, if the Tx queue is not full.
 *         1, if the Tx queue is full.
 */
static inline int octep_iq_full_check(struct octep_iq *iq)
{
        if (likely((IQ_INSTR_SPACE(iq)) >
                   OCTEP_WAKE_QUEUE_THRESHOLD))
                return 0;

        /* Stop the queue if unable to send */
        netif_stop_subqueue(iq->netdev, iq->q_no);

        /* Allow for pending updates in write index
         * from iq_process_completion in other cpus
         * to reflect, in case queue gets free
         * entries.
         */
        smp_mb();

        /* check again and restart the queue, in case NAPI has just freed
         * enough Tx ring entries.
         */
        if (unlikely(IQ_INSTR_SPACE(iq) >
                     OCTEP_WAKE_QUEUE_THRESHOLD)) {
                netif_start_subqueue(iq->netdev, iq->q_no);
                iq->stats->restart_cnt++;
                return 0;
        }

        return 1;
}

/**
 * octep_start_xmit() - Enqueue packet to Octoen hardware Tx Queue.
 *
 * @skb: packet skbuff pointer.
 * @netdev: kernel network device.
 *
 * Return: NETDEV_TX_BUSY, if Tx Queue is full.
 *         NETDEV_TX_OK, if successfully enqueued to hardware Tx queue.
 */
static netdev_tx_t octep_start_xmit(struct sk_buff *skb,
                                    struct net_device *netdev)
{
        struct octep_device *oct = netdev_priv(netdev);
        netdev_features_t feat  = netdev->features;
        struct octep_tx_sglist_desc *sglist;
        struct octep_tx_buffer *tx_buffer;
        struct octep_tx_desc_hw *hw_desc;
        struct skb_shared_info *shinfo;
        struct octep_instr_hdr *ih;
        struct octep_iq *iq;
        skb_frag_t *frag;
        u16 nr_frags, si;
        int xmit_more;
        u16 q_no, wi;

        if (skb_put_padto(skb, ETH_ZLEN))
                return NETDEV_TX_OK;

        q_no = skb_get_queue_mapping(skb);
        if (q_no >= oct->num_iqs) {
                netdev_err(netdev, "Invalid Tx skb->queue_mapping=%d\n", q_no);
                q_no = q_no % oct->num_iqs;
        }

        iq = oct->iq[q_no];

        shinfo = skb_shinfo(skb);
        nr_frags = shinfo->nr_frags;

        wi = iq->host_write_index;
        hw_desc = &iq->desc_ring[wi];
        hw_desc->ih64 = 0;

        tx_buffer = iq->buff_info + wi;
        tx_buffer->skb = skb;

        ih = &hw_desc->ih;
        ih->pkind = oct->conf->fw_info.pkind;
        ih->fsz = oct->conf->fw_info.fsz;
        ih->tlen = skb->len + ih->fsz;

        if (!nr_frags) {
                tx_buffer->gather = 0;
                tx_buffer->dma = dma_map_single(iq->dev, skb->data,
                                                skb->len, DMA_TO_DEVICE);
                if (dma_mapping_error(iq->dev, tx_buffer->dma))
                        goto dma_map_err;
                hw_desc->dptr = tx_buffer->dma;
        } else {
                /* Scatter/Gather */
                dma_addr_t dma;
                u16 len;

                sglist = tx_buffer->sglist;

                ih->gsz = nr_frags + 1;
                ih->gather = 1;
                tx_buffer->gather = 1;

                len = skb_headlen(skb);
                dma = dma_map_single(iq->dev, skb->data, len, DMA_TO_DEVICE);
                if (dma_mapping_error(iq->dev, dma))
                        goto dma_map_err;

                memset(sglist, 0, OCTEP_SGLIST_SIZE_PER_PKT);
                sglist[0].len[3] = len;
                sglist[0].dma_ptr[0] = dma;

                si = 1; /* entry 0 is main skb, mapped above */
                frag = &shinfo->frags[0];
                while (nr_frags--) {
                        len = skb_frag_size(frag);
                        dma = skb_frag_dma_map(iq->dev, frag, 0,
                                               len, DMA_TO_DEVICE);
                        if (dma_mapping_error(iq->dev, dma))
                                goto dma_map_sg_err;

                        sglist[si >> 2].len[3 - (si & 3)] = len;
                        sglist[si >> 2].dma_ptr[si & 3] = dma;

                        frag++;
                        si++;
                }
                hw_desc->dptr = tx_buffer->sglist_dma;
        }

        if (oct->conf->fw_info.tx_ol_flags) {
                if ((feat & (NETIF_F_TSO)) && (skb_is_gso(skb))) {
                        hw_desc->txm.ol_flags = OCTEP_TX_OFFLOAD_CKSUM;
                        hw_desc->txm.ol_flags |= OCTEP_TX_OFFLOAD_TSO;
                        hw_desc->txm.gso_size =  skb_shinfo(skb)->gso_size;
                        hw_desc->txm.gso_segs =  skb_shinfo(skb)->gso_segs;
                } else if (feat & (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM)) {
                        hw_desc->txm.ol_flags = OCTEP_TX_OFFLOAD_CKSUM;
                }
                /* due to ESR txm will be swapped by hw */
                hw_desc->txm64[0] = (__force u64)cpu_to_be64(hw_desc->txm64[0]);
        }

        xmit_more = netdev_xmit_more();

        __netdev_tx_sent_queue(iq->netdev_q, skb->len, xmit_more);

        skb_tx_timestamp(skb);
        iq->fill_cnt++;
        wi++;
        iq->host_write_index = wi & iq->ring_size_mask;

        /* octep_iq_full_check stops the queue and returns
         * true if so, in case the queue has become full
         * by inserting current packet. If so, we can
         * go ahead and ring doorbell.
         */
        if (!octep_iq_full_check(iq) && xmit_more &&
            iq->fill_cnt < iq->fill_threshold)
                return NETDEV_TX_OK;

        /* Flush the hw descriptor before writing to doorbell */
        wmb();
        /* Ring Doorbell to notify the NIC of new packets */
        writel(iq->fill_cnt, iq->doorbell_reg);
        iq->stats->instr_posted += iq->fill_cnt;
        iq->fill_cnt = 0;
        return NETDEV_TX_OK;

dma_map_sg_err:
        if (si > 0) {
                dma_unmap_single(iq->dev, sglist[0].dma_ptr[0],
                                 sglist[0].len[3], DMA_TO_DEVICE);
                sglist[0].len[3] = 0;
        }
        while (si > 1) {
                dma_unmap_page(iq->dev, sglist[si >> 2].dma_ptr[si & 3],
                               sglist[si >> 2].len[3 - (si & 3)], DMA_TO_DEVICE);
                sglist[si >> 2].len[3 - (si & 3)] = 0;
                si--;
        }
        tx_buffer->gather = 0;
dma_map_err:
        dev_kfree_skb_any(skb);
        return NETDEV_TX_OK;
}

/**
 * octep_get_stats64() - Get Octeon network device statistics.
 *
 * @netdev: kernel network device.
 * @stats: pointer to stats structure to be filled in.
 */
static void octep_get_stats64(struct net_device *netdev,
                              struct rtnl_link_stats64 *stats)
{
        struct octep_device *oct = netdev_priv(netdev);
        u64 tx_packets, tx_bytes, rx_packets, rx_bytes;
        int q;

        tx_packets = 0;
        tx_bytes = 0;
        rx_packets = 0;
        rx_bytes = 0;
        for (q = 0; q < OCTEP_MAX_QUEUES; q++) {
                tx_packets += oct->stats_iq[q].instr_completed;
                tx_bytes += oct->stats_iq[q].bytes_sent;
                rx_packets += oct->stats_oq[q].packets;
                rx_bytes += oct->stats_oq[q].bytes;
        }
        stats->tx_packets = tx_packets;
        stats->tx_bytes = tx_bytes;
        stats->rx_packets = rx_packets;
        stats->rx_bytes = rx_bytes;
}

/**
 * octep_tx_timeout_task - work queue task to Handle Tx queue timeout.
 *
 * @work: pointer to Tx queue timeout work_struct
 *
 * Stop and start the device so that it frees up all queue resources
 * and restarts the queues, that potentially clears a Tx queue timeout
 * condition.
 **/
static void octep_tx_timeout_task(struct work_struct *work)
{
        struct octep_device *oct = container_of(work, struct octep_device,
                                                tx_timeout_task);
        struct net_device *netdev = oct->netdev;

        rtnl_lock();
        if (netif_running(netdev)) {
                octep_stop(netdev);
                octep_open(netdev);
        }
        rtnl_unlock();
}

/**
 * octep_tx_timeout() - Handle Tx Queue timeout.
 *
 * @netdev: pointer to kernel network device.
 * @txqueue: Timed out Tx queue number.
 *
 * Schedule a work to handle Tx queue timeout.
 */
static void octep_tx_timeout(struct net_device *netdev, unsigned int txqueue)
{
        struct octep_device *oct = netdev_priv(netdev);

        queue_work(octep_wq, &oct->tx_timeout_task);
}

static int octep_set_mac(struct net_device *netdev, void *p)
{
        struct octep_device *oct = netdev_priv(netdev);
        struct sockaddr *addr = (struct sockaddr *)p;
        int err;

        if (!is_valid_ether_addr(addr->sa_data))
                return -EADDRNOTAVAIL;

        err = octep_ctrl_net_set_mac_addr(oct, OCTEP_CTRL_NET_INVALID_VFID,
                                          addr->sa_data, true);
        if (err)
                return err;

        memcpy(oct->mac_addr, addr->sa_data, ETH_ALEN);
        eth_hw_addr_set(netdev, addr->sa_data);

        return 0;
}

static int octep_change_mtu(struct net_device *netdev, int new_mtu)
{
        struct octep_device *oct = netdev_priv(netdev);
        struct octep_iface_link_info *link_info;
        int err = 0;

        link_info = &oct->link_info;
        if (link_info->mtu == new_mtu)
                return 0;

        err = octep_ctrl_net_set_mtu(oct, OCTEP_CTRL_NET_INVALID_VFID, new_mtu,
                                     true);
        if (!err) {
                oct->link_info.mtu = new_mtu;
                WRITE_ONCE(netdev->mtu, new_mtu);
        }

        return err;
}

static int octep_set_features(struct net_device *dev, netdev_features_t features)
{
        struct octep_ctrl_net_offloads offloads = { 0 };
        struct octep_device *oct = netdev_priv(dev);
        int err;

        /* We only support features received from firmware */
        if ((features & dev->hw_features) != features)
                return -EINVAL;

        if (features & NETIF_F_TSO)
                offloads.tx_offloads |= OCTEP_TX_OFFLOAD_TSO;

        if (features & NETIF_F_TSO6)
                offloads.tx_offloads |= OCTEP_TX_OFFLOAD_TSO;

        if (features & NETIF_F_IP_CSUM)
                offloads.tx_offloads |= OCTEP_TX_OFFLOAD_CKSUM;

        if (features & NETIF_F_IPV6_CSUM)
                offloads.tx_offloads |= OCTEP_TX_OFFLOAD_CKSUM;

        if (features & NETIF_F_RXCSUM)
                offloads.rx_offloads |= OCTEP_RX_OFFLOAD_CKSUM;

        err = octep_ctrl_net_set_offloads(oct,
                                          OCTEP_CTRL_NET_INVALID_VFID,
                                          &offloads,
                                          true);
        if (!err)
                dev->features = features;

        return err;
}

static bool octep_is_vf_valid(struct octep_device *oct, int vf)
{
        if (vf >= CFG_GET_ACTIVE_VFS(oct->conf)) {
                netdev_err(oct->netdev, "Invalid VF ID %d\n", vf);
                return false;
        }

        return true;
}

static int octep_get_vf_config(struct net_device *dev, int vf,
                               struct ifla_vf_info *ivi)
{
        struct octep_device *oct = netdev_priv(dev);

        if (!octep_is_vf_valid(oct, vf))
                return -EINVAL;

        ivi->vf = vf;
        ether_addr_copy(ivi->mac, oct->vf_info[vf].mac_addr);
        ivi->spoofchk = true;
        ivi->linkstate = IFLA_VF_LINK_STATE_ENABLE;
        ivi->trusted = false;

        return 0;
}

static int octep_set_vf_mac(struct net_device *dev, int vf, u8 *mac)
{
        struct octep_device *oct = netdev_priv(dev);
        int err;

        if (!octep_is_vf_valid(oct, vf))
                return -EINVAL;

        if (!is_valid_ether_addr(mac)) {
                dev_err(&oct->pdev->dev, "Invalid  MAC Address %pM\n", mac);
                return -EADDRNOTAVAIL;
        }

        dev_dbg(&oct->pdev->dev, "set vf-%d mac to %pM\n", vf, mac);
        ether_addr_copy(oct->vf_info[vf].mac_addr, mac);
        oct->vf_info[vf].flags |= OCTEON_PFVF_FLAG_MAC_SET_BY_PF;

        err = octep_ctrl_net_set_mac_addr(oct, vf, mac, true);
        if (err)
                dev_err(&oct->pdev->dev,
                        "Set VF%d MAC address failed via host control Mbox\n",
                        vf);

        return err;
}

static const struct net_device_ops octep_netdev_ops = {
        .ndo_open                = octep_open,
        .ndo_stop                = octep_stop,
        .ndo_start_xmit          = octep_start_xmit,
        .ndo_get_stats64         = octep_get_stats64,
        .ndo_tx_timeout          = octep_tx_timeout,
        .ndo_set_mac_address     = octep_set_mac,
        .ndo_change_mtu          = octep_change_mtu,
        .ndo_set_features        = octep_set_features,
        .ndo_get_vf_config       = octep_get_vf_config,
        .ndo_set_vf_mac          = octep_set_vf_mac
};

/**
 * octep_intr_poll_task - work queue task to process non-ioq interrupts.
 *
 * @work: pointer to mbox work_struct
 *
 * Process non-ioq interrupts to handle control mailbox, pfvf mailbox.
 **/
static void octep_intr_poll_task(struct work_struct *work)
{
        struct octep_device *oct = container_of(work, struct octep_device,
                                                intr_poll_task.work);

        if (!oct->poll_non_ioq_intr) {
                dev_info(&oct->pdev->dev, "Interrupt poll task stopped.\n");
                return;
        }

        oct->hw_ops.poll_non_ioq_interrupts(oct);
        queue_delayed_work(octep_wq, &oct->intr_poll_task,
                           msecs_to_jiffies(OCTEP_INTR_POLL_TIME_MSECS));
}

/**
 * octep_hb_timeout_task - work queue task to check firmware heartbeat.
 *
 * @work: pointer to hb work_struct
 *
 * Check for heartbeat miss count. Uninitialize oct device if miss count
 * exceeds configured max heartbeat miss count.
 *
 **/
static void octep_hb_timeout_task(struct work_struct *work)
{
        struct octep_device *oct = container_of(work, struct octep_device,
                                                hb_task.work);

        int miss_cnt;

        miss_cnt = atomic_inc_return(&oct->hb_miss_cnt);
        if (miss_cnt < oct->conf->fw_info.hb_miss_count) {
                queue_delayed_work(octep_wq, &oct->hb_task,
                                   msecs_to_jiffies(oct->conf->fw_info.hb_interval));
                return;
        }

        dev_err(&oct->pdev->dev, "Missed %u heartbeats. Uninitializing\n",
                miss_cnt);
        rtnl_lock();
        if (netif_running(oct->netdev))
                dev_close(oct->netdev);
        rtnl_unlock();
}

/**
 * octep_ctrl_mbox_task - work queue task to handle ctrl mbox messages.
 *
 * @work: pointer to ctrl mbox work_struct
 *
 * Poll ctrl mbox message queue and handle control messages from firmware.
 **/
static void octep_ctrl_mbox_task(struct work_struct *work)
{
        struct octep_device *oct = container_of(work, struct octep_device,
                                                ctrl_mbox_task);

        octep_ctrl_net_recv_fw_messages(oct);
}

static const char *octep_devid_to_str(struct octep_device *oct)
{
        switch (oct->chip_id) {
        case OCTEP_PCI_DEVICE_ID_CN98_PF:
                return "CN98XX";
        case OCTEP_PCI_DEVICE_ID_CN93_PF:
                return "CN93XX";
        case OCTEP_PCI_DEVICE_ID_CNF95N_PF:
                return "CNF95N";
        case OCTEP_PCI_DEVICE_ID_CN10KA_PF:
                return "CN10KA";
        case OCTEP_PCI_DEVICE_ID_CNF10KA_PF:
                return "CNF10KA";
        case OCTEP_PCI_DEVICE_ID_CNF10KB_PF:
                return "CNF10KB";
        case OCTEP_PCI_DEVICE_ID_CN10KB_PF:
                return "CN10KB";
        default:
                return "Unsupported";
        }
}

/**
 * octep_device_setup() - Setup Octeon Device.
 *
 * @oct: Octeon device private data structure.
 *
 * Setup Octeon device hardware operations, configuration, etc ...
 */
int octep_device_setup(struct octep_device *oct)
{
        struct pci_dev *pdev = oct->pdev;
        int i, ret;

        /* allocate memory for oct->conf */
        oct->conf = kzalloc_obj(*oct->conf);
        if (!oct->conf)
                return -ENOMEM;

        /* Map BAR regions */
        for (i = 0; i < OCTEP_MMIO_REGIONS; i++) {
                oct->mmio[i].hw_addr =
                        ioremap(pci_resource_start(oct->pdev, i * 2),
                                pci_resource_len(oct->pdev, i * 2));
                if (!oct->mmio[i].hw_addr)
                        goto unmap_prev;

                oct->mmio[i].mapped = 1;
        }

        oct->chip_id = pdev->device;
        oct->rev_id = pdev->revision;
        dev_info(&pdev->dev, "chip_id = 0x%x\n", pdev->device);

        switch (oct->chip_id) {
        case OCTEP_PCI_DEVICE_ID_CN98_PF:
        case OCTEP_PCI_DEVICE_ID_CN93_PF:
        case OCTEP_PCI_DEVICE_ID_CNF95N_PF:
                dev_info(&pdev->dev, "Setting up OCTEON %s PF PASS%d.%d\n",
                         octep_devid_to_str(oct), OCTEP_MAJOR_REV(oct),
                         OCTEP_MINOR_REV(oct));
                octep_device_setup_cn93_pf(oct);
                break;
        case OCTEP_PCI_DEVICE_ID_CNF10KA_PF:
        case OCTEP_PCI_DEVICE_ID_CN10KA_PF:
        case OCTEP_PCI_DEVICE_ID_CNF10KB_PF:
        case OCTEP_PCI_DEVICE_ID_CN10KB_PF:
                dev_info(&pdev->dev, "Setting up OCTEON %s PF PASS%d.%d\n",
                         octep_devid_to_str(oct), OCTEP_MAJOR_REV(oct), OCTEP_MINOR_REV(oct));
                octep_device_setup_cnxk_pf(oct);
                break;
        default:
                dev_err(&pdev->dev,
                        "%s: unsupported device\n", __func__);
                goto unsupported_dev;
        }


        ret = octep_ctrl_net_init(oct);
        if (ret)
                goto unsupported_dev;

        INIT_WORK(&oct->tx_timeout_task, octep_tx_timeout_task);
        INIT_WORK(&oct->ctrl_mbox_task, octep_ctrl_mbox_task);
        INIT_DELAYED_WORK(&oct->intr_poll_task, octep_intr_poll_task);
        oct->poll_non_ioq_intr = true;
        queue_delayed_work(octep_wq, &oct->intr_poll_task,
                           msecs_to_jiffies(OCTEP_INTR_POLL_TIME_MSECS));

        atomic_set(&oct->hb_miss_cnt, 0);
        INIT_DELAYED_WORK(&oct->hb_task, octep_hb_timeout_task);

        return 0;

unsupported_dev:
        i = OCTEP_MMIO_REGIONS;
unmap_prev:
        while (i--)
                iounmap(oct->mmio[i].hw_addr);

        kfree(oct->conf);
        return -1;
}

/**
 * octep_device_cleanup() - Cleanup Octeon Device.
 *
 * @oct: Octeon device private data structure.
 *
 * Cleanup Octeon device allocated resources.
 */
static void octep_device_cleanup(struct octep_device *oct)
{
        int i;

        oct->poll_non_ioq_intr = false;
        cancel_delayed_work_sync(&oct->intr_poll_task);
        cancel_work_sync(&oct->ctrl_mbox_task);

        dev_info(&oct->pdev->dev, "Cleaning up Octeon Device ...\n");

        for (i = 0; i < OCTEP_MAX_VF; i++) {
                vfree(oct->mbox[i]);
                oct->mbox[i] = NULL;
        }

        octep_delete_pfvf_mbox(oct);
        octep_ctrl_net_uninit(oct);
        cancel_delayed_work_sync(&oct->hb_task);

        oct->hw_ops.soft_reset(oct);
        for (i = 0; i < OCTEP_MMIO_REGIONS; i++) {
                if (oct->mmio[i].mapped)
                        iounmap(oct->mmio[i].hw_addr);
        }

        kfree(oct->conf);
        oct->conf = NULL;
}

static bool get_fw_ready_status(struct pci_dev *pdev)
{
        u32 pos = 0;
        u16 vsec_id;
        u8 status;

        while ((pos = pci_find_next_ext_capability(pdev, pos,
                                                   PCI_EXT_CAP_ID_VNDR))) {
                pci_read_config_word(pdev, pos + 4, &vsec_id);
#define FW_STATUS_VSEC_ID  0xA3
                if (vsec_id != FW_STATUS_VSEC_ID)
                        continue;

                pci_read_config_byte(pdev, (pos + 8), &status);
                dev_info(&pdev->dev, "Firmware ready status = %u\n", status);
#define FW_STATUS_READY 1ULL
                return status == FW_STATUS_READY;
        }
        return false;
}

/**
 * octep_probe() - Octeon PCI device probe handler.
 *
 * @pdev: PCI device structure.
 * @ent: entry in Octeon PCI device ID table.
 *
 * Initializes and enables the Octeon PCI device for network operations.
 * Initializes Octeon private data structure and registers a network device.
 */
static int octep_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
{
        struct octep_device *octep_dev = NULL;
        struct net_device *netdev;
        int max_rx_pktlen;
        int err;

        err = pci_enable_device(pdev);
        if (err) {
                dev_err(&pdev->dev, "Failed to enable PCI device\n");
                return  err;
        }

        err = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
        if (err) {
                dev_err(&pdev->dev, "Failed to set DMA mask !!\n");
                goto err_dma_mask;
        }

        err = pci_request_mem_regions(pdev, OCTEP_DRV_NAME);
        if (err) {
                dev_err(&pdev->dev, "Failed to map PCI memory regions\n");
                goto err_pci_regions;
        }

        pci_set_master(pdev);

        if (!get_fw_ready_status(pdev)) {
                dev_notice(&pdev->dev, "Firmware not ready; defer probe.\n");
                err = -EPROBE_DEFER;
                goto err_alloc_netdev;
        }

        netdev = alloc_etherdev_mq(sizeof(struct octep_device),
                                   OCTEP_MAX_QUEUES);
        if (!netdev) {
                dev_err(&pdev->dev, "Failed to allocate netdev\n");
                err = -ENOMEM;
                goto err_alloc_netdev;
        }
        SET_NETDEV_DEV(netdev, &pdev->dev);

        octep_dev = netdev_priv(netdev);
        octep_dev->netdev = netdev;
        octep_dev->pdev = pdev;
        octep_dev->dev = &pdev->dev;
        pci_set_drvdata(pdev, octep_dev);

        err = octep_device_setup(octep_dev);
        if (err) {
                dev_err(&pdev->dev, "Device setup failed\n");
                goto err_octep_config;
        }

        err = octep_setup_pfvf_mbox(octep_dev);
        if (err) {
                dev_err(&pdev->dev, "PF-VF mailbox setup failed\n");
                goto register_dev_err;
        }

        err = octep_ctrl_net_get_info(octep_dev, OCTEP_CTRL_NET_INVALID_VFID,
                                      &octep_dev->conf->fw_info);
        if (err) {
                dev_err(&pdev->dev, "Failed to get firmware info\n");
                goto register_dev_err;
        }
        dev_info(&octep_dev->pdev->dev, "Heartbeat interval %u msecs Heartbeat miss count %u\n",
                 octep_dev->conf->fw_info.hb_interval,
                 octep_dev->conf->fw_info.hb_miss_count);
        queue_delayed_work(octep_wq, &octep_dev->hb_task,
                           msecs_to_jiffies(octep_dev->conf->fw_info.hb_interval));

        netdev->netdev_ops = &octep_netdev_ops;
        octep_set_ethtool_ops(netdev);
        netif_carrier_off(netdev);

        netdev->hw_features = NETIF_F_SG;
        if (OCTEP_TX_IP_CSUM(octep_dev->conf->fw_info.tx_ol_flags))
                netdev->hw_features |= (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM);

        if (OCTEP_RX_IP_CSUM(octep_dev->conf->fw_info.rx_ol_flags))
                netdev->hw_features |= NETIF_F_RXCSUM;

        max_rx_pktlen = octep_ctrl_net_get_mtu(octep_dev, OCTEP_CTRL_NET_INVALID_VFID);
        if (max_rx_pktlen < 0) {
                dev_err(&octep_dev->pdev->dev,
                        "Failed to get max receive packet size; err = %d\n", max_rx_pktlen);
                err = max_rx_pktlen;
                goto register_dev_err;
        }
        netdev->min_mtu = OCTEP_MIN_MTU;
        netdev->max_mtu = max_rx_pktlen - (ETH_HLEN + ETH_FCS_LEN);
        netdev->mtu = OCTEP_DEFAULT_MTU;

        if (OCTEP_TX_TSO(octep_dev->conf->fw_info.tx_ol_flags)) {
                netdev->hw_features |= NETIF_F_TSO;
                netif_set_tso_max_size(netdev, netdev->max_mtu);
        }

        netdev->features |= netdev->hw_features;
        err = octep_ctrl_net_get_mac_addr(octep_dev, OCTEP_CTRL_NET_INVALID_VFID,
                                          octep_dev->mac_addr);
        if (err) {
                dev_err(&pdev->dev, "Failed to get mac address\n");
                goto register_dev_err;
        }
        eth_hw_addr_set(netdev, octep_dev->mac_addr);

        err = register_netdev(netdev);
        if (err) {
                dev_err(&pdev->dev, "Failed to register netdev\n");
                goto register_dev_err;
        }
        dev_info(&pdev->dev, "Device probe successful\n");
        return 0;

register_dev_err:
        octep_device_cleanup(octep_dev);
err_octep_config:
        free_netdev(netdev);
err_alloc_netdev:
        pci_release_mem_regions(pdev);
err_pci_regions:
err_dma_mask:
        pci_disable_device(pdev);
        return err;
}

static int octep_sriov_disable(struct octep_device *oct)
{
        struct pci_dev *pdev = oct->pdev;

        if (pci_vfs_assigned(oct->pdev)) {
                dev_warn(&pdev->dev, "Can't disable SRIOV while VFs are assigned\n");
                return -EPERM;
        }

        pci_disable_sriov(pdev);
        CFG_GET_ACTIVE_VFS(oct->conf) = 0;

        return 0;
}

/**
 * octep_remove() - Remove Octeon PCI device from driver control.
 *
 * @pdev: PCI device structure of the Octeon device.
 *
 * Cleanup all resources allocated for the Octeon device.
 * Unregister from network device and disable the PCI device.
 */
static void octep_remove(struct pci_dev *pdev)
{
        struct octep_device *oct = pci_get_drvdata(pdev);
        struct net_device *netdev;

        if (!oct)
                return;

        netdev = oct->netdev;
        octep_sriov_disable(oct);
        if (netdev->reg_state == NETREG_REGISTERED)
                unregister_netdev(netdev);

        cancel_work_sync(&oct->tx_timeout_task);
        octep_device_cleanup(oct);
        pci_release_mem_regions(pdev);
        free_netdev(netdev);
        pci_disable_device(pdev);
}

static int octep_sriov_enable(struct octep_device *oct, int num_vfs)
{
        struct pci_dev *pdev = oct->pdev;
        int err;

        CFG_GET_ACTIVE_VFS(oct->conf) = num_vfs;
        err = pci_enable_sriov(pdev, num_vfs);
        if (err) {
                dev_warn(&pdev->dev, "Failed to enable SRIOV err=%d\n", err);
                CFG_GET_ACTIVE_VFS(oct->conf) = 0;
                return err;
        }

        return num_vfs;
}

static int octep_sriov_configure(struct pci_dev *pdev, int num_vfs)
{
        struct octep_device *oct = pci_get_drvdata(pdev);
        int max_nvfs;

        if (num_vfs == 0)
                return octep_sriov_disable(oct);

        max_nvfs = CFG_GET_MAX_VFS(oct->conf);

        if (num_vfs > max_nvfs) {
                dev_err(&pdev->dev, "Invalid VF count Max supported VFs = %d\n",
                        max_nvfs);
                return -EINVAL;
        }

        return octep_sriov_enable(oct, num_vfs);
}

static struct pci_driver octep_driver = {
        .name = OCTEP_DRV_NAME,
        .id_table = octep_pci_id_tbl,
        .probe = octep_probe,
        .remove = octep_remove,
        .sriov_configure = octep_sriov_configure,
};

/**
 * octep_init_module() - Module initialiation.
 *
 * create common resource for the driver and register PCI driver.
 */
static int __init octep_init_module(void)
{
        int ret;

        pr_info("%s: Loading %s ...\n", OCTEP_DRV_NAME, OCTEP_DRV_STRING);

        /* work queue for all deferred tasks */
        octep_wq = create_singlethread_workqueue(OCTEP_DRV_NAME);
        if (!octep_wq) {
                pr_err("%s: Failed to create common workqueue\n",
                       OCTEP_DRV_NAME);
                return -ENOMEM;
        }

        ret = pci_register_driver(&octep_driver);
        if (ret < 0) {
                pr_err("%s: Failed to register PCI driver; err=%d\n",
                       OCTEP_DRV_NAME, ret);
                destroy_workqueue(octep_wq);
                return ret;
        }

        pr_info("%s: Loaded successfully !\n", OCTEP_DRV_NAME);

        return ret;
}

/**
 * octep_exit_module() - Module exit routine.
 *
 * unregister the driver with PCI subsystem and cleanup common resources.
 */
static void __exit octep_exit_module(void)
{
        pr_info("%s: Unloading ...\n", OCTEP_DRV_NAME);

        pci_unregister_driver(&octep_driver);
        destroy_workqueue(octep_wq);

        pr_info("%s: Unloading complete\n", OCTEP_DRV_NAME);
}

module_init(octep_init_module);
module_exit(octep_exit_module);