path: root/drivers/net/ethernet/intel/igc/igc_main.c

// SPDX-License-Identifier: GPL-2.0
/* Copyright (c)  2018 Intel Corporation */

#include <linux/module.h>
#include <linux/types.h>
#include <linux/if_vlan.h>
#include <linux/aer.h>

#include "igc.h"
#include "igc_hw.h"

#define DRV_VERSION	"0.0.1-k"
#define DRV_SUMMARY	"Intel(R) 2.5G Ethernet Linux Driver"

static int debug = -1;

MODULE_AUTHOR("Intel Corporation, <linux.nics@intel.com>");
MODULE_DESCRIPTION(DRV_SUMMARY);
MODULE_LICENSE("GPL v2");
MODULE_VERSION(DRV_VERSION);
module_param(debug, int, 0);
MODULE_PARM_DESC(debug, "Debug level (0=none,...,16=all)");

char igc_driver_name[] = "igc";
char igc_driver_version[] = DRV_VERSION;
static const char igc_driver_string[] = DRV_SUMMARY;
static const char igc_copyright[] =
	"Copyright(c) 2018 Intel Corporation.";

static const struct pci_device_id igc_pci_tbl[] = {
	{ PCI_VDEVICE(INTEL, IGC_DEV_ID_I225_LM) },
	{ PCI_VDEVICE(INTEL, IGC_DEV_ID_I225_V) },
	/* required last entry */
	{0, }
};

MODULE_DEVICE_TABLE(pci, igc_pci_tbl);

/* forward declaration */
static int igc_sw_init(struct igc_adapter *);
static void igc_configure(struct igc_adapter *adapter);
static void igc_power_down_link(struct igc_adapter *adapter);
static void igc_set_default_mac_filter(struct igc_adapter *adapter);
static void igc_write_itr(struct igc_q_vector *q_vector);
static void igc_assign_vector(struct igc_q_vector *q_vector, int msix_vector);
static void igc_free_q_vector(struct igc_adapter *adapter, int v_idx);
static void igc_set_interrupt_capability(struct igc_adapter *adapter,
					 bool msix);
static void igc_free_q_vectors(struct igc_adapter *adapter);
static void igc_irq_disable(struct igc_adapter *adapter);
static void igc_irq_enable(struct igc_adapter *adapter);
static void igc_configure_msix(struct igc_adapter *adapter);

enum latency_range {
	lowest_latency = 0,
	low_latency = 1,
	bulk_latency = 2,
	latency_invalid = 255
};

static void igc_reset(struct igc_adapter *adapter)
{
	if (!netif_running(adapter->netdev))
		igc_power_down_link(adapter);
}

/**
 * igc_power_up_link - Power up the phy/serdes link
 * @adapter: address of board private structure
 */
static void igc_power_up_link(struct igc_adapter *adapter)
{
}

/**
 * igc_power_down_link - Power down the phy/serdes link
 * @adapter: address of board private structure
 */
static void igc_power_down_link(struct igc_adapter *adapter)
{
}

/**
 * igc_release_hw_control - release control of the h/w to f/w
 * @adapter: address of board private structure
 *
 * igc_release_hw_control resets CTRL_EXT:DRV_LOAD bit.
 * For ASF and Pass Through versions of f/w this means that the
 * driver is no longer loaded.
 */
static void igc_release_hw_control(struct igc_adapter *adapter)
{
	struct igc_hw *hw = &adapter->hw;
	u32 ctrl_ext;

	/* Let firmware take over control of h/w */
	ctrl_ext = rd32(IGC_CTRL_EXT);
	wr32(IGC_CTRL_EXT,
	     ctrl_ext & ~IGC_CTRL_EXT_DRV_LOAD);
}

/**
 * igc_get_hw_control - get control of the h/w from f/w
 * @adapter: address of board private structure
 *
 * igc_get_hw_control sets CTRL_EXT:DRV_LOAD bit.
 * For ASF and Pass Through versions of f/w this means that
 * the driver is loaded.
 */
static void igc_get_hw_control(struct igc_adapter *adapter)
{
	struct igc_hw *hw = &adapter->hw;
	u32 ctrl_ext;

	/* Let firmware know the driver has taken over */
	ctrl_ext = rd32(IGC_CTRL_EXT);
	wr32(IGC_CTRL_EXT,
	     ctrl_ext | IGC_CTRL_EXT_DRV_LOAD);
}

/**
 * igc_set_mac - Change the Ethernet Address of the NIC
 * @netdev: network interface device structure
 * @p: pointer to an address structure
 *
 * Returns 0 on success, negative on failure
 */
static int igc_set_mac(struct net_device *netdev, void *p)
{
	struct igc_adapter *adapter = netdev_priv(netdev);
	struct igc_hw *hw = &adapter->hw;
	struct sockaddr *addr = p;

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

	memcpy(netdev->dev_addr, addr->sa_data, netdev->addr_len);
	memcpy(hw->mac.addr, addr->sa_data, netdev->addr_len);

	/* set the correct pool for the new PF MAC address in entry 0 */
	igc_set_default_mac_filter(adapter);

	return 0;
}

static netdev_tx_t igc_xmit_frame(struct sk_buff *skb,
				  struct net_device *netdev)
{
	dev_kfree_skb_any(skb);
	return NETDEV_TX_OK;
}

/**
 * igc_ioctl - I/O control method
 * @netdev: network interface device structure
 * @ifreq: frequency
 * @cmd: command
 */
static int igc_ioctl(struct net_device *netdev, struct ifreq *ifr, int cmd)
{
	switch (cmd) {
	default:
		return -EOPNOTSUPP;
	}
}

/**
 * igc_up - Open the interface and prepare it to handle traffic
 * @adapter: board private structure
 */
static void igc_up(struct igc_adapter *adapter)
{
	struct igc_hw *hw = &adapter->hw;
	int i = 0;

	/* hardware has been reset, we need to reload some things */
	igc_configure(adapter);

	clear_bit(__IGC_DOWN, &adapter->state);

	for (i = 0; i < adapter->num_q_vectors; i++)
		napi_enable(&adapter->q_vector[i]->napi);

	if (adapter->msix_entries)
		igc_configure_msix(adapter);
	else
		igc_assign_vector(adapter->q_vector[0], 0);

	/* Clear any pending interrupts. */
	rd32(IGC_ICR);
	igc_irq_enable(adapter);
}

/**
 * igc_update_stats - Update the board statistics counters
 * @adapter: board private structure
 */
static void igc_update_stats(struct igc_adapter *adapter)
{
}

/**
 * igc_down - Close the interface
 * @adapter: board private structure
 */
static void igc_down(struct igc_adapter *adapter)
{
	struct net_device *netdev = adapter->netdev;
	int i = 0;

	set_bit(__IGC_DOWN, &adapter->state);

	/* set trans_start so we don't get spurious watchdogs during reset */
	netif_trans_update(netdev);

	netif_carrier_off(netdev);
	netif_tx_stop_all_queues(netdev);

	for (i = 0; i < adapter->num_q_vectors; i++)
		napi_disable(&adapter->q_vector[i]->napi);

	adapter->link_speed = 0;
	adapter->link_duplex = 0;
}

/**
 * igc_change_mtu - Change the Maximum Transfer Unit
 * @netdev: network interface device structure
 * @new_mtu: new value for maximum frame size
 *
 * Returns 0 on success, negative on failure
 */
static int igc_change_mtu(struct net_device *netdev, int new_mtu)
{
	int max_frame = new_mtu + ETH_HLEN + ETH_FCS_LEN + VLAN_HLEN;
	struct igc_adapter *adapter = netdev_priv(netdev);
	struct pci_dev *pdev = adapter->pdev;

	/* adjust max frame to be at least the size of a standard frame */
	if (max_frame < (ETH_FRAME_LEN + ETH_FCS_LEN))
		max_frame = ETH_FRAME_LEN + ETH_FCS_LEN;

	while (test_and_set_bit(__IGC_RESETTING, &adapter->state))
		usleep_range(1000, 2000);

	/* igc_down has a dependency on max_frame_size */
	adapter->max_frame_size = max_frame;

	if (netif_running(netdev))
		igc_down(adapter);

	dev_info(&pdev->dev, "changing MTU from %d to %d\n",
		 netdev->mtu, new_mtu);
	netdev->mtu = new_mtu;

	if (netif_running(netdev))
		igc_up(adapter);
	else
		igc_reset(adapter);

	clear_bit(__IGC_RESETTING, &adapter->state);

	return 0;
}

/**
 * igc_get_stats - Get System Network Statistics
 * @netdev: network interface device structure
 *
 * Returns the address of the device statistics structure.
 * The statistics are updated here and also from the timer callback.
 */
static struct net_device_stats *igc_get_stats(struct net_device *netdev)
{
	struct igc_adapter *adapter = netdev_priv(netdev);

	if (!test_bit(__IGC_RESETTING, &adapter->state))
		igc_update_stats(adapter);

	/* only return the current stats */
	return &netdev->stats;
}

/**
 * igc_configure - configure the hardware for RX and TX
 * @adapter: private board structure
 */
static void igc_configure(struct igc_adapter *adapter)
{
	igc_get_hw_control(adapter);
}

/**
 * igc_rar_set_index - Sync RAL[index] and RAH[index] registers with MAC table
 * @adapter: Pointer to adapter structure
 * @index: Index of the RAR entry which need to be synced with MAC table
 */
static void igc_rar_set_index(struct igc_adapter *adapter, u32 index)
{
	u8 *addr = adapter->mac_table[index].addr;
	struct igc_hw *hw = &adapter->hw;
	u32 rar_low, rar_high;

	/* HW expects these to be in network order when they are plugged
	 * into the registers which are little endian.  In order to guarantee
	 * that ordering we need to do an leXX_to_cpup here in order to be
	 * ready for the byteswap that occurs with writel
	 */
	rar_low = le32_to_cpup((__le32 *)(addr));
	rar_high = le16_to_cpup((__le16 *)(addr + 4));

	/* Indicate to hardware the Address is Valid. */
	if (adapter->mac_table[index].state & IGC_MAC_STATE_IN_USE) {
		if (is_valid_ether_addr(addr))
			rar_high |= IGC_RAH_AV;

		rar_high |= IGC_RAH_POOL_1 <<
			adapter->mac_table[index].queue;
	}

	wr32(IGC_RAL(index), rar_low);
	wrfl();
	wr32(IGC_RAH(index), rar_high);
	wrfl();
}

/* Set default MAC address for the PF in the first RAR entry */
static void igc_set_default_mac_filter(struct igc_adapter *adapter)
{
	struct igc_mac_addr *mac_table = &adapter->mac_table[0];

	ether_addr_copy(mac_table->addr, adapter->hw.mac.addr);
	mac_table->state = IGC_MAC_STATE_DEFAULT | IGC_MAC_STATE_IN_USE;

	igc_rar_set_index(adapter, 0);
}

/**
 * igc_msix_other - msix other interrupt handler
 * @irq: interrupt number
 * @data: pointer to a q_vector
 */
static irqreturn_t igc_msix_other(int irq, void *data)
{
	struct igc_adapter *adapter = data;
	struct igc_hw *hw = &adapter->hw;
	u32 icr = rd32(IGC_ICR);

	/* reading ICR causes bit 31 of EICR to be cleared */
	if (icr & IGC_ICR_DRSTA)
		schedule_work(&adapter->reset_task);

	if (icr & IGC_ICR_DOUTSYNC) {
		/* HW is reporting DMA is out of sync */
		adapter->stats.doosync++;
	}

	if (icr & IGC_ICR_LSC) {
		hw->mac.get_link_status = 1;
		/* guard against interrupt when we're going down */
		if (!test_bit(__IGC_DOWN, &adapter->state))
			mod_timer(&adapter->watchdog_timer, jiffies + 1);
	}

	wr32(IGC_EIMS, adapter->eims_other);

	return IRQ_HANDLED;
}

/**
 * igc_write_ivar - configure ivar for given MSI-X vector
 * @hw: pointer to the HW structure
 * @msix_vector: vector number we are allocating to a given ring
 * @index: row index of IVAR register to write within IVAR table
 * @offset: column offset of in IVAR, should be multiple of 8
 *
 * The IVAR table consists of 2 columns,
 * each containing an cause allocation for an Rx and Tx ring, and a
 * variable number of rows depending on the number of queues supported.
 */
static void igc_write_ivar(struct igc_hw *hw, int msix_vector,
			   int index, int offset)
{
	u32 ivar = array_rd32(IGC_IVAR0, index);

	/* clear any bits that are currently set */
	ivar &= ~((u32)0xFF << offset);

	/* write vector and valid bit */
	ivar |= (msix_vector | IGC_IVAR_VALID) << offset;

	array_wr32(IGC_IVAR0, index, ivar);
}

static void igc_assign_vector(struct igc_q_vector *q_vector, int msix_vector)
{
	struct igc_adapter *adapter = q_vector->adapter;
	struct igc_hw *hw = &adapter->hw;
	int rx_queue = IGC_N0_QUEUE;
	int tx_queue = IGC_N0_QUEUE;

	if (q_vector->rx.ring)
		rx_queue = q_vector->rx.ring->reg_idx;
	if (q_vector->tx.ring)
		tx_queue = q_vector->tx.ring->reg_idx;

	switch (hw->mac.type) {
	case igc_i225:
		if (rx_queue > IGC_N0_QUEUE)
			igc_write_ivar(hw, msix_vector,
				       rx_queue >> 1,
				       (rx_queue & 0x1) << 4);
		if (tx_queue > IGC_N0_QUEUE)
			igc_write_ivar(hw, msix_vector,
				       tx_queue >> 1,
				       ((tx_queue & 0x1) << 4) + 8);
		q_vector->eims_value = BIT(msix_vector);
		break;
	default:
		WARN_ONCE(hw->mac.type != igc_i225, "Wrong MAC type\n");
		break;
	}

	/* add q_vector eims value to global eims_enable_mask */
	adapter->eims_enable_mask |= q_vector->eims_value;

	/* configure q_vector to set itr on first interrupt */
	q_vector->set_itr = 1;
}

/**
 * igc_configure_msix - Configure MSI-X hardware
 * @adapter: Pointer to adapter structure
 *
 * igc_configure_msix sets up the hardware to properly
 * generate MSI-X interrupts.
 */
static void igc_configure_msix(struct igc_adapter *adapter)
{
	struct igc_hw *hw = &adapter->hw;
	int i, vector = 0;
	u32 tmp;

	adapter->eims_enable_mask = 0;

	/* set vector for other causes, i.e. link changes */
	switch (hw->mac.type) {
	case igc_i225:
		/* Turn on MSI-X capability first, or our settings
		 * won't stick.  And it will take days to debug.
		 */
		wr32(IGC_GPIE, IGC_GPIE_MSIX_MODE |
		     IGC_GPIE_PBA | IGC_GPIE_EIAME |
		     IGC_GPIE_NSICR);

		/* enable msix_other interrupt */
		adapter->eims_other = BIT(vector);
		tmp = (vector++ | IGC_IVAR_VALID) << 8;

		wr32(IGC_IVAR_MISC, tmp);
		break;
	default:
		/* do nothing, since nothing else supports MSI-X */
		break;
	} /* switch (hw->mac.type) */

	adapter->eims_enable_mask |= adapter->eims_other;

	for (i = 0; i < adapter->num_q_vectors; i++)
		igc_assign_vector(adapter->q_vector[i], vector++);

	wrfl();
}

static irqreturn_t igc_msix_ring(int irq, void *data)
{
	struct igc_q_vector *q_vector = data;

	/* Write the ITR value calculated from the previous interrupt. */
	igc_write_itr(q_vector);

	napi_schedule(&q_vector->napi);

	return IRQ_HANDLED;
}

/**
 * igc_request_msix - Initialize MSI-X interrupts
 * @adapter: Pointer to adapter structure
 *
 * igc_request_msix allocates MSI-X vectors and requests interrupts from the
 * kernel.
 */
static int igc_request_msix(struct igc_adapter *adapter)
{
	int i = 0, err = 0, vector = 0, free_vector = 0;
	struct net_device *netdev = adapter->netdev;

	err = request_irq(adapter->msix_entries[vector].vector,
			  &igc_msix_other, 0, netdev->name, adapter);
	if (err)
		goto err_out;

	for (i = 0; i < adapter->num_q_vectors; i++) {
		struct igc_q_vector *q_vector = adapter->q_vector[i];

		vector++;

		q_vector->itr_register = adapter->io_addr + IGC_EITR(vector);

		if (q_vector->rx.ring && q_vector->tx.ring)
			sprintf(q_vector->name, "%s-TxRx-%u", netdev->name,
				q_vector->rx.ring->queue_index);
		else if (q_vector->tx.ring)
			sprintf(q_vector->name, "%s-tx-%u", netdev->name,
				q_vector->tx.ring->queue_index);
		else if (q_vector->rx.ring)
			sprintf(q_vector->name, "%s-rx-%u", netdev->name,
				q_vector->rx.ring->queue_index);
		else
			sprintf(q_vector->name, "%s-unused", netdev->name);

		err = request_irq(adapter->msix_entries[vector].vector,
				  igc_msix_ring, 0, q_vector->name,
				  q_vector);
		if (err)
			goto err_free;
	}

	igc_configure_msix(adapter);
	return 0;

err_free:
	/* free already assigned IRQs */
	free_irq(adapter->msix_entries[free_vector++].vector, adapter);

	vector--;
	for (i = 0; i < vector; i++) {
		free_irq(adapter->msix_entries[free_vector++].vector,
			 adapter->q_vector[i]);
	}
err_out:
	return err;
}

/**
 * igc_reset_q_vector - Reset config for interrupt vector
 * @adapter: board private structure to initialize
 * @v_idx: Index of vector to be reset
 *
 * If NAPI is enabled it will delete any references to the
 * NAPI struct. This is preparation for igc_free_q_vector.
 */
static void igc_reset_q_vector(struct igc_adapter *adapter, int v_idx)
{
	struct igc_q_vector *q_vector = adapter->q_vector[v_idx];

	/* if we're coming from igc_set_interrupt_capability, the vectors are
	 * not yet allocated
	 */
	if (!q_vector)
		return;

	if (q_vector->tx.ring)
		adapter->tx_ring[q_vector->tx.ring->queue_index] = NULL;

	if (q_vector->rx.ring)
		adapter->rx_ring[q_vector->rx.ring->queue_index] = NULL;

	netif_napi_del(&q_vector->napi);
}

static void igc_reset_interrupt_capability(struct igc_adapter *adapter)
{
	int v_idx = adapter->num_q_vectors;

	if (adapter->msix_entries) {
		pci_disable_msix(adapter->pdev);
		kfree(adapter->msix_entries);
		adapter->msix_entries = NULL;
	} else if (adapter->flags & IGC_FLAG_HAS_MSI) {
		pci_disable_msi(adapter->pdev);
	}

	while (v_idx--)
		igc_reset_q_vector(adapter, v_idx);
}

/**
 * igc_clear_interrupt_scheme - reset the device to a state of no interrupts
 * @adapter: Pointer to adapter structure
 *
 * This function resets the device so that it has 0 rx queues, tx queues, and
 * MSI-X interrupts allocated.
 */
static void igc_clear_interrupt_scheme(struct igc_adapter *adapter)
{
	igc_free_q_vectors(adapter);
	igc_reset_interrupt_capability(adapter);
}

/**
 * igc_free_q_vectors - Free memory allocated for interrupt vectors
 * @adapter: board private structure to initialize
 *
 * This function frees the memory allocated to the q_vectors.  In addition if
 * NAPI is enabled it will delete any references to the NAPI struct prior
 * to freeing the q_vector.
 */
static void igc_free_q_vectors(struct igc_adapter *adapter)
{
	int v_idx = adapter->num_q_vectors;

	adapter->num_tx_queues = 0;
	adapter->num_rx_queues = 0;
	adapter->num_q_vectors = 0;

	while (v_idx--) {
		igc_reset_q_vector(adapter, v_idx);
		igc_free_q_vector(adapter, v_idx);
	}
}

/**
 * igc_free_q_vector - Free memory allocated for specific interrupt vector
 * @adapter: board private structure to initialize
 * @v_idx: Index of vector to be freed
 *
 * This function frees the memory allocated to the q_vector.
 */
static void igc_free_q_vector(struct igc_adapter *adapter, int v_idx)
{
	struct igc_q_vector *q_vector = adapter->q_vector[v_idx];

	adapter->q_vector[v_idx] = NULL;

	/* igc_get_stats64() might access the rings on this vector,
	 * we must wait a grace period before freeing it.
	 */
	if (q_vector)
		kfree_rcu(q_vector, rcu);
}

/**
 * igc_update_ring_itr - update the dynamic ITR value based on packet size
 * @q_vector: pointer to q_vector
 *
 * Stores a new ITR value based on strictly on packet size.  This
 * algorithm is less sophisticated than that used in igc_update_itr,
 * due to the difficulty of synchronizing statistics across multiple
 * receive rings.  The divisors and thresholds used by this function
 * were determined based on theoretical maximum wire speed and testing
 * data, in order to minimize response time while increasing bulk
 * throughput.
 * NOTE: This function is called only when operating in a multiqueue
 * receive environment.
 */
static void igc_update_ring_itr(struct igc_q_vector *q_vector)
{
	struct igc_adapter *adapter = q_vector->adapter;
	int new_val = q_vector->itr_val;
	int avg_wire_size = 0;
	unsigned int packets;

	/* For non-gigabit speeds, just fix the interrupt rate at 4000
	 * ints/sec - ITR timer value of 120 ticks.
	 */
	switch (adapter->link_speed) {
	case SPEED_10:
	case SPEED_100:
		new_val = IGC_4K_ITR;
		goto set_itr_val;
	default:
		break;
	}

	packets = q_vector->rx.total_packets;
	if (packets)
		avg_wire_size = q_vector->rx.total_bytes / packets;

	packets = q_vector->tx.total_packets;
	if (packets)
		avg_wire_size = max_t(u32, avg_wire_size,
				      q_vector->tx.total_bytes / packets);

	/* if avg_wire_size isn't set no work was done */
	if (!avg_wire_size)
		goto clear_counts;

	/* Add 24 bytes to size to account for CRC, preamble, and gap */
	avg_wire_size += 24;

	/* Don't starve jumbo frames */
	avg_wire_size = min(avg_wire_size, 3000);

	/* Give a little boost to mid-size frames */
	if (avg_wire_size > 300 && avg_wire_size < 1200)
		new_val = avg_wire_size / 3;
	else
		new_val = avg_wire_size / 2;

	/* conservative mode (itr 3) eliminates the lowest_latency setting */
	if (new_val < IGC_20K_ITR &&
	    ((q_vector->rx.ring && adapter->rx_itr_setting == 3) ||
	    (!q_vector->rx.ring && adapter->tx_itr_setting == 3)))
		new_val = IGC_20K_ITR;

set_itr_val:
	if (new_val != q_vector->itr_val) {
		q_vector->itr_val = new_val;
		q_vector->set_itr = 1;
	}
clear_counts:
	q_vector->rx.total_bytes = 0;
	q_vector->rx.total_packets = 0;
	q_vector->tx.total_bytes = 0;
	q_vector->tx.total_packets = 0;
}

/**
 * igc_update_itr - update the dynamic ITR value based on statistics
 * @q_vector: pointer to q_vector
 * @ring_container: ring info to update the itr for
 *
 * Stores a new ITR value based on packets and byte
 * counts during the last interrupt.  The advantage of per interrupt
 * computation is faster updates and more accurate ITR for the current
 * traffic pattern.  Constants in this function were computed
 * based on theoretical maximum wire speed and thresholds were set based
 * on testing data as well as attempting to minimize response time
 * while increasing bulk throughput.
 * NOTE: These calculations are only valid when operating in a single-
 * queue environment.
 */
static void igc_update_itr(struct igc_q_vector *q_vector,
			   struct igc_ring_container *ring_container)
{
	unsigned int packets = ring_container->total_packets;
	unsigned int bytes = ring_container->total_bytes;
	u8 itrval = ring_container->itr;

	/* no packets, exit with status unchanged */
	if (packets == 0)
		return;

	switch (itrval) {
	case lowest_latency:
		/* handle TSO and jumbo frames */
		if (bytes / packets > 8000)
			itrval = bulk_latency;
		else if ((packets < 5) && (bytes > 512))
			itrval = low_latency;
		break;
	case low_latency:  /* 50 usec aka 20000 ints/s */
		if (bytes > 10000) {
			/* this if handles the TSO accounting */
			if (bytes / packets > 8000)
				itrval = bulk_latency;
			else if ((packets < 10) || ((bytes / packets) > 1200))
				itrval = bulk_latency;
			else if ((packets > 35))
				itrval = lowest_latency;
		} else if (bytes / packets > 2000) {
			itrval = bulk_latency;
		} else if (packets <= 2 && bytes < 512) {
			itrval = lowest_latency;
		}
		break;
	case bulk_latency: /* 250 usec aka 4000 ints/s */
		if (bytes > 25000) {
			if (packets > 35)
				itrval = low_latency;
		} else if (bytes < 1500) {
			itrval = low_latency;
		}
		break;
	}

	/* clear work counters since we have the values we need */
	ring_container->total_bytes = 0;
	ring_container->total_packets = 0;

	/* write updated itr to ring container */
	ring_container->itr = itrval;
}

static void igc_set_itr(struct igc_q_vector *q_vector)
{
	struct igc_adapter *adapter = q_vector->adapter;
	u32 new_itr = q_vector->itr_val;
	u8 current_itr = 0;

	/* for non-gigabit speeds, just fix the interrupt rate at 4000 */
	switch (adapter->link_speed) {
	case SPEED_10:
	case SPEED_100:
		current_itr = 0;
		new_itr = IGC_4K_ITR;
		goto set_itr_now;
	default:
		break;
	}

	igc_update_itr(q_vector, &q_vector->tx);
	igc_update_itr(q_vector, &q_vector->rx);

	current_itr = max(q_vector->rx.itr, q_vector->tx.itr);

	/* conservative mode (itr 3) eliminates the lowest_latency setting */
	if (current_itr == lowest_latency &&
	    ((q_vector->rx.ring && adapter->rx_itr_setting == 3) ||
	    (!q_vector->rx.ring && adapter->tx_itr_setting == 3)))
		current_itr = low_latency;

	switch (current_itr) {
	/* counts and packets in update_itr are dependent on these numbers */
	case lowest_latency:
		new_itr = IGC_70K_ITR; /* 70,000 ints/sec */
		break;
	case low_latency:
		new_itr = IGC_20K_ITR; /* 20,000 ints/sec */
		break;
	case bulk_latency:
		new_itr = IGC_4K_ITR;  /* 4,000 ints/sec */
		break;
	default:
		break;
	}

set_itr_now:
	if (new_itr != q_vector->itr_val) {
		/* this attempts to bias the interrupt rate towards Bulk
		 * by adding intermediate steps when interrupt rate is
		 * increasing
		 */
		new_itr = new_itr > q_vector->itr_val ?
			  max((new_itr * q_vector->itr_val) /
			  (new_itr + (q_vector->itr_val >> 2)),
			  new_itr) : new_itr;
		/* Don't write the value here; it resets the adapter's
		 * internal timer, and causes us to delay far longer than
		 * we should between interrupts.  Instead, we write the ITR
		 * value at the beginning of the next interrupt so the timing
		 * ends up being correct.
		 */
		q_vector->itr_val = new_itr;
		q_vector->set_itr = 1;
	}
}

static void igc_ring_irq_enable(struct igc_q_vector *q_vector)
{
	struct igc_adapter *adapter = q_vector->adapter;
	struct igc_hw *hw = &adapter->hw;

	if ((q_vector->rx.ring && (adapter->rx_itr_setting & 3)) ||
	    (!q_vector->rx.ring && (adapter->tx_itr_setting & 3))) {
		if (adapter->num_q_vectors == 1)
			igc_set_itr(q_vector);
		else
			igc_update_ring_itr(q_vector);
	}

	if (!test_bit(__IGC_DOWN, &adapter->state)) {
		if (adapter->msix_entries)
			wr32(IGC_EIMS, q_vector->eims_value);
		else
			igc_irq_enable(adapter);
	}
}

/**
 * igc_poll - NAPI Rx polling callback
 * @napi: napi polling structure
 * @budget: count of how many packets we should handle
 */
static int igc_poll(struct napi_struct *napi, int budget)
{
	struct igc_q_vector *q_vector = container_of(napi,
						     struct igc_q_vector,
						     napi);
	bool clean_complete = true;
	int work_done = 0;
	int cleaned = 0;

	if (q_vector->rx.ring) {
		work_done += cleaned;
		if (cleaned >= budget)
			clean_complete = false;
	}

	/* If all work not completed, return budget and keep polling */
	if (!clean_complete)
		return budget;

	/* If not enough Rx work done, exit the polling mode */
	napi_complete_done(napi, work_done);
	igc_ring_irq_enable(q_vector);

	return 0;
}

/**
 * igc_set_interrupt_capability - set MSI or MSI-X if supported
 * @adapter: Pointer to adapter structure
 *
 * Attempt to configure interrupts using the best available
 * capabilities of the hardware and kernel.
 */
static void igc_set_interrupt_capability(struct igc_adapter *adapter,
					 bool msix)
{
	int numvecs, i;
	int err;

	if (!msix)
		goto msi_only;
	adapter->flags |= IGC_FLAG_HAS_MSIX;

	/* Number of supported queues. */
	adapter->num_rx_queues = adapter->rss_queues;

	adapter->num_tx_queues = adapter->rss_queues;

	/* start with one vector for every Rx queue */
	numvecs = adapter->num_rx_queues;

	/* if Tx handler is separate add 1 for every Tx queue */
	if (!(adapter->flags & IGC_FLAG_QUEUE_PAIRS))
		numvecs += adapter->num_tx_queues;

	/* store the number of vectors reserved for queues */
	adapter->num_q_vectors = numvecs;

	/* add 1 vector for link status interrupts */
	numvecs++;

	adapter->msix_entries = kcalloc(numvecs, sizeof(struct msix_entry),
					GFP_KERNEL);

	if (!adapter->msix_entries)
		return;

	/* populate entry values */
	for (i = 0; i < numvecs; i++)
		adapter->msix_entries[i].entry = i;

	err = pci_enable_msix_range(adapter->pdev,
				    adapter->msix_entries,
				    numvecs,
				    numvecs);
	if (err > 0)
		return;

	kfree(adapter->msix_entries);
	adapter->msix_entries = NULL;

	igc_reset_interrupt_capability(adapter);

msi_only:
	adapter->flags &= ~IGC_FLAG_HAS_MSIX;

	adapter->rss_queues = 1;
	adapter->flags |= IGC_FLAG_QUEUE_PAIRS;
	adapter->num_rx_queues = 1;
	adapter->num_tx_queues = 1;
	adapter->num_q_vectors = 1;
	if (!pci_enable_msi(adapter->pdev))
		adapter->flags |= IGC_FLAG_HAS_MSI;
}

static void igc_add_ring(struct igc_ring *ring,
			 struct igc_ring_container *head)
{
	head->ring = ring;
	head->count++;
}

/**
 * igc_alloc_q_vector - Allocate memory for a single interrupt vector
 * @adapter: board private structure to initialize
 * @v_count: q_vectors allocated on adapter, used for ring interleaving
 * @v_idx: index of vector in adapter struct
 * @txr_count: total number of Tx rings to allocate
 * @txr_idx: index of first Tx ring to allocate
 * @rxr_count: total number of Rx rings to allocate
 * @rxr_idx: index of first Rx ring to allocate
 *
 * We allocate one q_vector.  If allocation fails we return -ENOMEM.
 */
static int igc_alloc_q_vector(struct igc_adapter *adapter,
			      unsigned int v_count, unsigned int v_idx,
			      unsigned int txr_count, unsigned int txr_idx,
			      unsigned int rxr_count, unsigned int rxr_idx)
{
	struct igc_q_vector *q_vector;
	struct igc_ring *ring;
	int ring_count, size;

	/* igc only supports 1 Tx and/or 1 Rx queue per vector */
	if (txr_count > 1 || rxr_count > 1)
		return -ENOMEM;

	ring_count = txr_count + rxr_count;
	size = sizeof(struct igc_q_vector) +
		(sizeof(struct igc_ring) * ring_count);

	/* allocate q_vector and rings */
	q_vector = adapter->q_vector[v_idx];
	if (!q_vector)
		q_vector = kzalloc(size, GFP_KERNEL);
	else
		memset(q_vector, 0, size);
	if (!q_vector)
		return -ENOMEM;

	/* initialize NAPI */
	netif_napi_add(adapter->netdev, &q_vector->napi,
		       igc_poll, 64);

	/* tie q_vector and adapter together */
	adapter->q_vector[v_idx] = q_vector;
	q_vector->adapter = adapter;

	/* initialize work limits */
	q_vector->tx.work_limit = adapter->tx_work_limit;

	/* initialize ITR configuration */
	q_vector->itr_register = adapter->io_addr + IGC_EITR(0);
	q_vector->itr_val = IGC_START_ITR;

	/* initialize pointer to rings */
	ring = q_vector->ring;

	/* initialize ITR */
	if (rxr_count) {
		/* rx or rx/tx vector */
		if (!adapter->rx_itr_setting || adapter->rx_itr_setting > 3)
			q_vector->itr_val = adapter->rx_itr_setting;
	} else {
		/* tx only vector */
		if (!adapter->tx_itr_setting || adapter->tx_itr_setting > 3)
			q_vector->itr_val = adapter->tx_itr_setting;
	}

	if (txr_count) {
		/* assign generic ring traits */
		ring->dev = &adapter->pdev->dev;
		ring->netdev = adapter->netdev;

		/* configure backlink on ring */
		ring->q_vector = q_vector;

		/* update q_vector Tx values */
		igc_add_ring(ring, &q_vector->tx);

		/* apply Tx specific ring traits */
		ring->count = adapter->tx_ring_count;
		ring->queue_index = txr_idx;

		/* assign ring to adapter */
		adapter->tx_ring[txr_idx] = ring;

		/* push pointer to next ring */
		ring++;
	}

	if (rxr_count) {
		/* assign generic ring traits */
		ring->dev = &adapter->pdev->dev;
		ring->netdev = adapter->netdev;

		/* configure backlink on ring */
		ring->q_vector = q_vector;

		/* update q_vector Rx values */
		igc_add_ring(ring, &q_vector->rx);

		/* apply Rx specific ring traits */
		ring->count = adapter->rx_ring_count;
		ring->queue_index = rxr_idx;

		/* assign ring to adapter */
		adapter->rx_ring[rxr_idx] = ring;
	}

	return 0;
}

/**
 * igc_alloc_q_vectors - Allocate memory for interrupt vectors
 * @adapter: board private structure to initialize
 *
 * We allocate one q_vector per queue interrupt.  If allocation fails we
 * return -ENOMEM.
 */
static int igc_alloc_q_vectors(struct igc_adapter *adapter)
{
	int rxr_remaining = adapter->num_rx_queues;
	int txr_remaining = adapter->num_tx_queues;
	int rxr_idx = 0, txr_idx = 0, v_idx = 0;
	int q_vectors = adapter->num_q_vectors;
	int err;

	if (q_vectors >= (rxr_remaining + txr_remaining)) {
		for (; rxr_remaining; v_idx++) {
			err = igc_alloc_q_vector(adapter, q_vectors, v_idx,
						 0, 0, 1, rxr_idx);

			if (err)
				goto err_out;

			/* update counts and index */
			rxr_remaining--;
			rxr_idx++;
		}
	}

	for (; v_idx < q_vectors; v_idx++) {
		int rqpv = DIV_ROUND_UP(rxr_remaining, q_vectors - v_idx);
		int tqpv = DIV_ROUND_UP(txr_remaining, q_vectors - v_idx);

		err = igc_alloc_q_vector(adapter, q_vectors, v_idx,
					 tqpv, txr_idx, rqpv, rxr_idx);

		if (err)
			goto err_out;

		/* update counts and index */
		rxr_remaining -= rqpv;
		txr_remaining -= tqpv;
		rxr_idx++;
		txr_idx++;
	}

	return 0;

err_out:
	adapter->num_tx_queues = 0;
	adapter->num_rx_queues = 0;
	adapter->num_q_vectors = 0;

	while (v_idx--)
		igc_free_q_vector(adapter, v_idx);

	return -ENOMEM;
}

/**
 * igc_init_interrupt_scheme - initialize interrupts, allocate queues/vectors
 * @adapter: Pointer to adapter structure
 *
 * This function initializes the interrupts and allocates all of the queues.
 */
static int igc_init_interrupt_scheme(struct igc_adapter *adapter, bool msix)
{
	struct pci_dev *pdev = adapter->pdev;
	int err = 0;

	igc_set_interrupt_capability(adapter, msix);

	err = igc_alloc_q_vectors(adapter);
	if (err) {
		dev_err(&pdev->dev, "Unable to allocate memory for vectors\n");
		goto err_alloc_q_vectors;
	}

	return 0;

err_alloc_q_vectors:
	igc_reset_interrupt_capability(adapter);
	return err;
}

static void igc_free_irq(struct igc_adapter *adapter)
{
	if (adapter->msix_entries) {
		int vector = 0, i;

		free_irq(adapter->msix_entries[vector++].vector, adapter);

		for (i = 0; i < adapter->num_q_vectors; i++)
			free_irq(adapter->msix_entries[vector++].vector,
				 adapter->q_vector[i]);
	} else {
		free_irq(adapter->pdev->irq, adapter);
	}
}

/**
 * igc_irq_disable - Mask off interrupt generation on the NIC
 * @adapter: board private structure
 */
static void igc_irq_disable(struct igc_adapter *adapter)
{
	struct igc_hw *hw = &adapter->hw;

	if (adapter->msix_entries) {
		u32 regval = rd32(IGC_EIAM);

		wr32(IGC_EIAM, regval & ~adapter->eims_enable_mask);
		wr32(IGC_EIMC, adapter->eims_enable_mask);
		regval = rd32(IGC_EIAC);
		wr32(IGC_EIAC, regval & ~adapter->eims_enable_mask);
	}

	wr32(IGC_IAM, 0);
	wr32(IGC_IMC, ~0);
	wrfl();

	if (adapter->msix_entries) {
		int vector = 0, i;

		synchronize_irq(adapter->msix_entries[vector++].vector);

		for (i = 0; i < adapter->num_q_vectors; i++)
			synchronize_irq(adapter->msix_entries[vector++].vector);
	} else {
		synchronize_irq(adapter->pdev->irq);
	}
}

/**
 * igc_irq_enable - Enable default interrupt generation settings
 * @adapter: board private structure
 */
static void igc_irq_enable(struct igc_adapter *adapter)
{
	struct igc_hw *hw = &adapter->hw;

	if (adapter->msix_entries) {
		u32 ims = IGC_IMS_LSC | IGC_IMS_DOUTSYNC | IGC_IMS_DRSTA;
		u32 regval = rd32(IGC_EIAC);

		wr32(IGC_EIAC, regval | adapter->eims_enable_mask);
		regval = rd32(IGC_EIAM);
		wr32(IGC_EIAM, regval | adapter->eims_enable_mask);
		wr32(IGC_EIMS, adapter->eims_enable_mask);
		wr32(IGC_IMS, ims);
	} else {
		wr32(IGC_IMS, IMS_ENABLE_MASK | IGC_IMS_DRSTA);
		wr32(IGC_IAM, IMS_ENABLE_MASK | IGC_IMS_DRSTA);
	}
}

/**
 * igc_request_irq - initialize interrupts
 * @adapter: Pointer to adapter structure
 *
 * Attempts to configure interrupts using the best available
 * capabilities of the hardware and kernel.
 */
static int igc_request_irq(struct igc_adapter *adapter)
{
	int err = 0;

	if (adapter->flags & IGC_FLAG_HAS_MSIX) {
		err = igc_request_msix(adapter);
		if (!err)
			goto request_done;
		/* fall back to MSI */

		igc_clear_interrupt_scheme(adapter);
		err = igc_init_interrupt_scheme(adapter, false);
		if (err)
			goto request_done;
		igc_configure(adapter);
	}

request_done:
	return err;
}

static void igc_write_itr(struct igc_q_vector *q_vector)
{
	u32 itr_val = q_vector->itr_val & IGC_QVECTOR_MASK;

	if (!q_vector->set_itr)
		return;

	if (!itr_val)
		itr_val = IGC_ITR_VAL_MASK;

	itr_val |= IGC_EITR_CNT_IGNR;

	writel(itr_val, q_vector->itr_register);
	q_vector->set_itr = 0;
}

/**
 * igc_open - Called when a network interface is made active
 * @netdev: network interface device structure
 *
 * Returns 0 on success, negative value on failure
 *
 * The open entry point is called when a network interface is made
 * active by the system (IFF_UP).  At this point all resources needed
 * for transmit and receive operations are allocated, the interrupt
 * handler is registered with the OS, the watchdog timer is started,
 * and the stack is notified that the interface is ready.
 */
static int __igc_open(struct net_device *netdev, bool resuming)
{
	struct igc_adapter *adapter = netdev_priv(netdev);
	struct igc_hw *hw = &adapter->hw;
	int err = 0;
	int i = 0;

	/* disallow open during test */

	if (test_bit(__IGC_TESTING, &adapter->state)) {
		WARN_ON(resuming);
		return -EBUSY;
	}

	netif_carrier_off(netdev);

	igc_power_up_link(adapter);

	igc_configure(adapter);

	err = igc_request_irq(adapter);
	if (err)
		goto err_req_irq;

	/* Notify the stack of the actual queue counts. */
	netif_set_real_num_tx_queues(netdev, adapter->num_tx_queues);
	if (err)
		goto err_set_queues;

	err = netif_set_real_num_rx_queues(netdev, adapter->num_rx_queues);
	if (err)
		goto err_set_queues;

	clear_bit(__IGC_DOWN, &adapter->state);

	for (i = 0; i < adapter->num_q_vectors; i++)
		napi_enable(&adapter->q_vector[i]->napi);

	/* Clear any pending interrupts. */
	rd32(IGC_ICR);
	igc_irq_enable(adapter);

	/* start the watchdog. */
	hw->mac.get_link_status = 1;

	return IGC_SUCCESS;

err_set_queues:
	igc_free_irq(adapter);
err_req_irq:
	igc_release_hw_control(adapter);
	igc_power_down_link(adapter);

	return err;
}

static int igc_open(struct net_device *netdev)
{
	return __igc_open(netdev, false);
}

/**
 * igc_close - Disables a network interface
 * @netdev: network interface device structure
 *
 * Returns 0, this is not allowed to fail
 *
 * The close entry point is called when an interface is de-activated
 * by the OS.  The hardware is still under the driver's control, but
 * needs to be disabled.  A global MAC reset is issued to stop the
 * hardware, and all transmit and receive resources are freed.
 */
static int __igc_close(struct net_device *netdev, bool suspending)
{
	struct igc_adapter *adapter = netdev_priv(netdev);

	WARN_ON(test_bit(__IGC_RESETTING, &adapter->state));

	igc_down(adapter);

	igc_release_hw_control(adapter);

	igc_free_irq(adapter);

	return 0;
}

static int igc_close(struct net_device *netdev)
{
	if (netif_device_present(netdev) || netdev->dismantle)
		return __igc_close(netdev, false);
	return 0;
}

static const struct net_device_ops igc_netdev_ops = {
	.ndo_open		= igc_open,
	.ndo_stop		= igc_close,
	.ndo_start_xmit		= igc_xmit_frame,
	.ndo_set_mac_address	= igc_set_mac,
	.ndo_change_mtu		= igc_change_mtu,
	.ndo_get_stats		= igc_get_stats,
	.ndo_do_ioctl		= igc_ioctl,
};

/* PCIe configuration access */
void igc_read_pci_cfg(struct igc_hw *hw, u32 reg, u16 *value)
{
	struct igc_adapter *adapter = hw->back;

	pci_read_config_word(adapter->pdev, reg, value);
}

void igc_write_pci_cfg(struct igc_hw *hw, u32 reg, u16 *value)
{
	struct igc_adapter *adapter = hw->back;

	pci_write_config_word(adapter->pdev, reg, *value);
}

s32 igc_read_pcie_cap_reg(struct igc_hw *hw, u32 reg, u16 *value)
{
	struct igc_adapter *adapter = hw->back;
	u16 cap_offset;

	cap_offset = pci_find_capability(adapter->pdev, PCI_CAP_ID_EXP);
	if (!cap_offset)
		return -IGC_ERR_CONFIG;

	pci_read_config_word(adapter->pdev, cap_offset + reg, value);

	return IGC_SUCCESS;
}

s32 igc_write_pcie_cap_reg(struct igc_hw *hw, u32 reg, u16 *value)
{
	struct igc_adapter *adapter = hw->back;
	u16 cap_offset;

	cap_offset = pci_find_capability(adapter->pdev, PCI_CAP_ID_EXP);
	if (!cap_offset)
		return -IGC_ERR_CONFIG;

	pci_write_config_word(adapter->pdev, cap_offset + reg, *value);

	return IGC_SUCCESS;
}

u32 igc_rd32(struct igc_hw *hw, u32 reg)
{
	struct igc_adapter *igc = container_of(hw, struct igc_adapter, hw);
	u8 __iomem *hw_addr = READ_ONCE(hw->hw_addr);
	u32 value = 0;

	if (IGC_REMOVED(hw_addr))
		return ~value;

	value = readl(&hw_addr[reg]);

	/* reads should not return all F's */
	if (!(~value) && (!reg || !(~readl(hw_addr)))) {
		struct net_device *netdev = igc->netdev;

		hw->hw_addr = NULL;
		netif_device_detach(netdev);
		netdev_err(netdev, "PCIe link lost, device now detached\n");
	}

	return value;
}

/**
 * igc_probe - Device Initialization Routine
 * @pdev: PCI device information struct
 * @ent: entry in igc_pci_tbl
 *
 * Returns 0 on success, negative on failure
 *
 * igc_probe initializes an adapter identified by a pci_dev structure.
 * The OS initialization, configuring the adapter private structure,
 * and a hardware reset occur.
 */
static int igc_probe(struct pci_dev *pdev,
		     const struct pci_device_id *ent)
{
	struct igc_adapter *adapter;
	struct net_device *netdev;
	struct igc_hw *hw;
	int err, pci_using_dac;

	err = pci_enable_device_mem(pdev);
	if (err)
		return err;

	pci_using_dac = 0;
	err = dma_set_mask(&pdev->dev, DMA_BIT_MASK(64));
	if (!err) {
		err = dma_set_coherent_mask(&pdev->dev,
					    DMA_BIT_MASK(64));
		if (!err)
			pci_using_dac = 1;
	} else {
		err = dma_set_mask(&pdev->dev, DMA_BIT_MASK(32));
		if (err) {
			err = dma_set_coherent_mask(&pdev->dev,
						    DMA_BIT_MASK(32));
			if (err) {
				IGC_ERR("Wrong DMA configuration, aborting\n");
				goto err_dma;
			}
		}
	}

	err = pci_request_selected_regions(pdev,
					   pci_select_bars(pdev,
							   IORESOURCE_MEM),
					   igc_driver_name);
	if (err)
		goto err_pci_reg;

	pci_enable_pcie_error_reporting(pdev);

	pci_set_master(pdev);

	err = -ENOMEM;
	netdev = alloc_etherdev_mq(sizeof(struct igc_adapter),
				   IGC_MAX_TX_QUEUES);

	if (!netdev)
		goto err_alloc_etherdev;

	SET_NETDEV_DEV(netdev, &pdev->dev);

	pci_set_drvdata(pdev, netdev);
	adapter = netdev_priv(netdev);
	adapter->netdev = netdev;
	adapter->pdev = pdev;
	hw = &adapter->hw;
	hw->back = adapter;
	adapter->port_num = hw->bus.func;
	adapter->msg_enable = GENMASK(debug - 1, 0);

	err = pci_save_state(pdev);
	if (err)
		goto err_ioremap;

	err = -EIO;
	adapter->io_addr = ioremap(pci_resource_start(pdev, 0),
				   pci_resource_len(pdev, 0));
	if (!adapter->io_addr)
		goto err_ioremap;

	/* hw->hw_addr can be zeroed, so use adapter->io_addr for unmap */
	hw->hw_addr = adapter->io_addr;

	netdev->netdev_ops = &igc_netdev_ops;

	netdev->watchdog_timeo = 5 * HZ;

	netdev->mem_start = pci_resource_start(pdev, 0);
	netdev->mem_end = pci_resource_end(pdev, 0);

	/* PCI config space info */
	hw->vendor_id = pdev->vendor;
	hw->device_id = pdev->device;
	hw->revision_id = pdev->revision;
	hw->subsystem_vendor_id = pdev->subsystem_vendor;
	hw->subsystem_device_id = pdev->subsystem_device;

	/* setup the private structure */
	err = igc_sw_init(adapter);
	if (err)
		goto err_sw_init;

	/* MTU range: 68 - 9216 */
	netdev->min_mtu = ETH_MIN_MTU;
	netdev->max_mtu = MAX_STD_JUMBO_FRAME_SIZE;

	/* reset the hardware with the new settings */
	igc_reset(adapter);

	/* let the f/w know that the h/w is now under the control of the
	 * driver.
	 */
	igc_get_hw_control(adapter);

	strncpy(netdev->name, "eth%d", IFNAMSIZ);
	err = register_netdev(netdev);
	if (err)
		goto err_register;

	 /* carrier off reporting is important to ethtool even BEFORE open */
	netif_carrier_off(netdev);

	/* print pcie link status and MAC address */
	pcie_print_link_status(pdev);
	netdev_info(netdev, "MAC: %pM\n", netdev->dev_addr);

	return 0;

err_register:
	igc_release_hw_control(adapter);
err_sw_init:
	igc_clear_interrupt_scheme(adapter);
	iounmap(adapter->io_addr);
err_ioremap:
	free_netdev(netdev);
err_alloc_etherdev:
	pci_release_selected_regions(pdev,
				     pci_select_bars(pdev, IORESOURCE_MEM));
err_pci_reg:
err_dma:
	pci_disable_device(pdev);
	return err;
}

/**
 * igc_remove - Device Removal Routine
 * @pdev: PCI device information struct
 *
 * igc_remove is called by the PCI subsystem to alert the driver
 * that it should release a PCI device.  This could be caused by a
 * Hot-Plug event, or because the driver is going to be removed from
 * memory.
 */
static void igc_remove(struct pci_dev *pdev)
{
	struct net_device *netdev = pci_get_drvdata(pdev);
	struct igc_adapter *adapter = netdev_priv(netdev);

	set_bit(__IGC_DOWN, &adapter->state);
	flush_scheduled_work();

	/* Release control of h/w to f/w.  If f/w is AMT enabled, this
	 * would have already happened in close and is redundant.
	 */
	igc_release_hw_control(adapter);
	unregister_netdev(netdev);

	pci_release_selected_regions(pdev,
				     pci_select_bars(pdev, IORESOURCE_MEM));

	free_netdev(netdev);
	pci_disable_device(pdev);
}

static struct pci_driver igc_driver = {
	.name     = igc_driver_name,
	.id_table = igc_pci_tbl,
	.probe    = igc_probe,
	.remove   = igc_remove,
};

/**
 * igc_sw_init - Initialize general software structures (struct igc_adapter)
 * @adapter: board private structure to initialize
 *
 * igc_sw_init initializes the Adapter private data structure.
 * Fields are initialized based on PCI device information and
 * OS network device settings (MTU size).
 */
static int igc_sw_init(struct igc_adapter *adapter)
{
	struct net_device *netdev = adapter->netdev;
	struct pci_dev *pdev = adapter->pdev;
	struct igc_hw *hw = &adapter->hw;

	/* PCI config space info */

	hw->vendor_id = pdev->vendor;
	hw->device_id = pdev->device;
	hw->subsystem_vendor_id = pdev->subsystem_vendor;
	hw->subsystem_device_id = pdev->subsystem_device;

	pci_read_config_byte(pdev, PCI_REVISION_ID, &hw->revision_id);

	pci_read_config_word(pdev, PCI_COMMAND, &hw->bus.pci_cmd_word);

	/* adjust max frame to be at least the size of a standard frame */
	adapter->max_frame_size = netdev->mtu + ETH_HLEN + ETH_FCS_LEN +
					VLAN_HLEN;

	if (igc_init_interrupt_scheme(adapter, true)) {
		dev_err(&pdev->dev, "Unable to allocate memory for queues\n");
		return -ENOMEM;
	}

	/* Explicitly disable IRQ since the NIC can be in any state. */
	igc_irq_disable(adapter);

	set_bit(__IGC_DOWN, &adapter->state);

	return 0;
}

/**
 * igc_init_module - Driver Registration Routine
 *
 * igc_init_module is the first routine called when the driver is
 * loaded. All it does is register with the PCI subsystem.
 */
static int __init igc_init_module(void)
{
	int ret;

	pr_info("%s - version %s\n",
		igc_driver_string, igc_driver_version);

	pr_info("%s\n", igc_copyright);

	ret = pci_register_driver(&igc_driver);
	return ret;
}

module_init(igc_init_module);

/**
 * igc_exit_module - Driver Exit Cleanup Routine
 *
 * igc_exit_module is called just before the driver is removed
 * from memory.
 */
static void __exit igc_exit_module(void)
{
	pci_unregister_driver(&igc_driver);
}

module_exit(igc_exit_module);
/* igc_main.c */