source: mainline/uspace/drv/nic/e1k/e1k.c@ 815b244a

/*
 * Copyright (c) 2011 Zdenek Bouska
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/** @file e1k.c
 *
 * Driver for Intel Pro/1000 8254x Family of Gigabit Ethernet Controllers
 *
 */

#include <assert.h>
#include <stdio.h>
#include <errno.h>
#include <adt/list.h>
#include <align.h>
#include <byteorder.h>
#include <sysinfo.h>
#include <ipc/irc.h>
#include <ipc/ns.h>
#include <libarch/ddi.h>
#include <as.h>
#include <ddf/log.h>
#include <ddf/interrupt.h>
#include <devman.h>
#include <device/hw_res_parsed.h>
#include <device/pci.h>
#include <nic.h>
#include <nil_remote.h>
#include <ops/nic.h>
#include "e1k.h"

#define NAME  "e1k"

#define E1000_DEFAULT_INTERRUPT_INTERVAL_USEC  250

/* Must be power of 8 */
#define E1000_RX_FRAME_COUNT  128
#define E1000_TX_FRAME_COUNT  128

#define E1000_RECEIVE_ADDRESS  16

/** Maximum sending frame size */
#define E1000_MAX_SEND_FRAME_SIZE  2048
/** Maximum receiving frame size */
#define E1000_MAX_RECEIVE_FRAME_SIZE  2048

/** nic_driver_data_t* -> e1000_t* cast */
#define DRIVER_DATA_NIC(nic) \
        ((e1000_t *) nic_get_specific(nic))

/** device_t* -> nic_driver_data_t* cast */
#define NIC_DATA_DEV(dev) \
        ((nic_t *) ((dev)->driver_data))

/** device_t* -> e1000_t* cast */
#define DRIVER_DATA_DEV(dev) \
        (DRIVER_DATA_NIC(NIC_DATA_DEV(dev)))

/** Cast pointer to uint64_t
 *
 * @param ptr Pointer to cast
 *
 * @return The uint64_t pointer representation.
 *
 */
#define PTR_TO_U64(ptr)  ((uint64_t) ((uintptr_t) (ptr)))

/** Cast the memaddr part to the void*
 *
 * @param memaddr The memaddr value
 *
 */
#define MEMADDR_TO_PTR(memaddr)  ((void *) ((size_t) (memaddr)))

#define E1000_REG_BASE(e1000) \
        ((e1000)->reg_base_virt)

#define E1000_REG_ADDR(e1000, reg) \
        ((uint32_t *) (E1000_REG_BASE(e1000) + reg))

#define E1000_REG_READ(e1000, reg) \
        (pio_read_32(E1000_REG_ADDR(e1000, reg)))

#define E1000_REG_WRITE(e1000, reg, value) \
        (pio_write_32(E1000_REG_ADDR(e1000, reg), value))

/** E1000 device data */
typedef struct {
        /** Device configuration */
        e1000_info_t info;
        
        /** Physical registers base address */
        void *reg_base_phys;
        /** Virtual registers base address */
        void *reg_base_virt;
        
        /** Physical tx ring address */
        void *tx_ring_phys;
        /** Virtual tx ring address */
        void *tx_ring_virt;
        
        /** Ring of TX frames, physical address */
        void **tx_frame_phys;
        /** Ring of TX frames, virtual address */
        void **tx_frame_virt;
        
        /** Physical rx ring address */
        void *rx_ring_phys;
        /** Virtual rx ring address */
        void *rx_ring_virt;
        
        /** Ring of RX frames, physical address */
        void **rx_frame_phys;
        /** Ring of RX frames, virtual address */
        void **rx_frame_virt;
        
        /** VLAN tag */
        uint16_t vlan_tag;
        
        /** Add VLAN tag to frame */
        bool vlan_tag_add;
        
        /** Used unicast Receive Address count */
        unsigned int unicast_ra_count;
        
        /** Used milticast Receive addrress count */
        unsigned int multicast_ra_count;
        
        /** The irq assigned */
        int irq;
        
        /** Lock for CTRL register */
        fibril_mutex_t ctrl_lock;
        
        /** Lock for receiver */
        fibril_mutex_t rx_lock;
        
        /** Lock for transmitter */
        fibril_mutex_t tx_lock;
        
        /** Lock for EEPROM access */
        fibril_mutex_t eeprom_lock;
} e1000_t;

/** Global mutex for work with shared irq structure */
FIBRIL_MUTEX_INITIALIZE(irq_reg_mutex);

static int e1000_get_address(e1000_t *, nic_address_t *);
static void e1000_eeprom_get_address(e1000_t *, nic_address_t *);
static int e1000_set_addr(ddf_fun_t *, const nic_address_t *);

static int e1000_defective_get_mode(ddf_fun_t *, uint32_t *);
static int e1000_defective_set_mode(ddf_fun_t *, uint32_t);

static int e1000_get_cable_state(ddf_fun_t *, nic_cable_state_t *);
static int e1000_get_device_info(ddf_fun_t *, nic_device_info_t *);
static int e1000_get_operation_mode(ddf_fun_t *, int *,
    nic_channel_mode_t *, nic_role_t *);
static int e1000_set_operation_mode(ddf_fun_t *, int,
    nic_channel_mode_t, nic_role_t);
static int e1000_autoneg_enable(ddf_fun_t *, uint32_t);
static int e1000_autoneg_disable(ddf_fun_t *);
static int e1000_autoneg_restart(ddf_fun_t *);

static int e1000_vlan_set_tag(ddf_fun_t *, uint16_t, bool, bool);

/** Network interface options for E1000 card driver */
static nic_iface_t e1000_nic_iface;

/** Network interface options for E1000 card driver */
static nic_iface_t e1000_nic_iface = {
        .set_address = &e1000_set_addr,
        .get_device_info = &e1000_get_device_info,
        .get_cable_state = &e1000_get_cable_state,
        .get_operation_mode = &e1000_get_operation_mode,
        .set_operation_mode = &e1000_set_operation_mode,
        .autoneg_enable = &e1000_autoneg_enable,
        .autoneg_disable = &e1000_autoneg_disable,
        .autoneg_restart = &e1000_autoneg_restart,
        .vlan_set_tag = &e1000_vlan_set_tag,
        .defective_get_mode = &e1000_defective_get_mode,
        .defective_set_mode = &e1000_defective_set_mode,
};

/** Basic device operations for E1000 driver */
static ddf_dev_ops_t e1000_dev_ops;

static int e1000_dev_add(ddf_dev_t *);

/** Basic driver operations for E1000 driver */
static driver_ops_t e1000_driver_ops = {
        .dev_add = e1000_dev_add
};

/** Driver structure for E1000 driver */
static driver_t e1000_driver = {
        .name = NAME,
        .driver_ops = &e1000_driver_ops
};

/* The default implementation callbacks */
static int e1000_on_activating(nic_t *);
static int e1000_on_stopping(nic_t *);
static void e1000_send_frame(nic_t *, void *, size_t);

/** Commands to deal with interrupt
 *
 */
irq_cmd_t e1000_irq_commands[] = {
        {
                /* Get the interrupt status */
                .cmd = CMD_PIO_READ_32,
                .addr = NULL,
                .dstarg = 2
        },
        {
                .cmd = CMD_PREDICATE,
                .value = 2,
                .srcarg = 2
        },
        {
                /* Disable interrupts until interrupt routine is finished */
                .cmd = CMD_PIO_WRITE_32,
                .addr = NULL,
                .value = 0xffffffff
        },
        {
                .cmd = CMD_ACCEPT
        }
};

/** Interrupt code definition */
irq_code_t e1000_irq_code = {
        .cmdcount = sizeof(e1000_irq_commands) / sizeof(irq_cmd_t),
        .cmds = e1000_irq_commands
};

/** Get the device information
 *
 * @param dev  NIC device
 * @param info Information to fill
 *
 * @return EOK
 *
 */
static int e1000_get_device_info(ddf_fun_t *dev, nic_device_info_t *info)
{
        assert(dev);
        assert(info);
        
        bzero(info, sizeof(nic_device_info_t));
        
        info->vendor_id = 0x8086;
        str_cpy(info->vendor_name, NIC_VENDOR_MAX_LENGTH,
            "Intel Corporation");
        str_cpy(info->model_name, NIC_MODEL_MAX_LENGTH,
            "Intel Pro");
        
        info->ethernet_support[ETH_10M] = ETH_10BASE_T;
        info->ethernet_support[ETH_100M] = ETH_100BASE_TX;
        info->ethernet_support[ETH_1000M] = ETH_1000BASE_T;
        
        return EOK;
}

/** Check the cable state
 *
 * @param[in]  dev   device
 * @param[out] state state to fill
 *
 * @return EOK
 *
 */
static int e1000_get_cable_state(ddf_fun_t *dev, nic_cable_state_t *state)
{
        assert(dev);
        assert(DRIVER_DATA_DEV(dev));
        assert(state);
        
        e1000_t *e1000 = DRIVER_DATA_DEV(dev);
        if (E1000_REG_READ(e1000, E1000_STATUS) & (STATUS_LU))
                *state = NIC_CS_PLUGGED;
        else
                *state = NIC_CS_UNPLUGGED;
        
        return EOK;
}

static uint16_t e1000_calculate_itr_interval_from_usecs(suseconds_t useconds)
{
        return useconds * 4;
}

/** Get operation mode of the device
 *
 */
static int e1000_get_operation_mode(ddf_fun_t *dev, int *speed,
    nic_channel_mode_t *duplex, nic_role_t *role)
{
        e1000_t *e1000 = DRIVER_DATA_DEV(dev);
        uint32_t status = E1000_REG_READ(e1000, E1000_STATUS);
        
        if (status & STATUS_FD)
                *duplex = NIC_CM_FULL_DUPLEX;
        else
                *duplex = NIC_CM_HALF_DUPLEX;
        
        uint32_t speed_bits =
            (status >> STATUS_SPEED_SHIFT) & STATUS_SPEED_ALL;
        
        if (speed_bits == STATUS_SPEED_10)
                *speed = 10;
        else if (speed_bits == STATUS_SPEED_100)
                *speed = 100;
        else if ((speed_bits == STATUS_SPEED_1000A) ||
            (speed_bits == STATUS_SPEED_1000B))
                *speed = 1000;
        
        *role = NIC_ROLE_UNKNOWN;
        return EOK;
}

static void e1000_link_restart(e1000_t *e1000)
{
        fibril_mutex_lock(&e1000->ctrl_lock);
        
        uint32_t ctrl = E1000_REG_READ(e1000, E1000_CTRL);
        
        if (ctrl & CTRL_SLU) {
                ctrl &= ~(CTRL_SLU);
                fibril_mutex_unlock(&e1000->ctrl_lock);
                usleep(10);
                fibril_mutex_lock(&e1000->ctrl_lock);
                ctrl |= CTRL_SLU;
        }
        
        fibril_mutex_unlock(&e1000->ctrl_lock);
        
        e1000_link_restart(e1000);
}

/** Set operation mode of the device
 *
 */
static int e1000_set_operation_mode(ddf_fun_t *dev, int speed,
    nic_channel_mode_t duplex, nic_role_t role)
{
        if ((speed != 10) && (speed != 100) && (speed != 1000))
                return EINVAL;
        
        if ((duplex != NIC_CM_HALF_DUPLEX) && (duplex != NIC_CM_FULL_DUPLEX))
                return EINVAL;
        
        e1000_t *e1000 = DRIVER_DATA_DEV(dev);
        
        fibril_mutex_lock(&e1000->ctrl_lock);
        uint32_t ctrl = E1000_REG_READ(e1000, E1000_CTRL);
        
        ctrl |= CTRL_FRCSPD;
        ctrl |= CTRL_FRCDPLX;
        ctrl &= ~(CTRL_ASDE);
        
        if (duplex == NIC_CM_FULL_DUPLEX)
                ctrl |= CTRL_FD;
        else
                ctrl &= ~(CTRL_FD);
        
        ctrl &= ~(CTRL_SPEED_MASK);
        if (speed == 1000)
                ctrl |= CTRL_SPEED_1000 << CTRL_SPEED_SHIFT;
        else if (speed == 100)
                ctrl |= CTRL_SPEED_100 << CTRL_SPEED_SHIFT;
        else
                ctrl |= CTRL_SPEED_10 << CTRL_SPEED_SHIFT;
        
        E1000_REG_WRITE(e1000, E1000_CTRL, ctrl);
        
        fibril_mutex_unlock(&e1000->ctrl_lock);
        
        e1000_link_restart(e1000);
        
        return EOK;
}

/** Enable auto-negotiation
 *
 * @param dev           Device to update
 * @param advertisement Ignored on E1000
 *
 * @return EOK if advertisement mode set successfully
 *
 */
static int e1000_autoneg_enable(ddf_fun_t *dev, uint32_t advertisement)
{
        e1000_t *e1000 = DRIVER_DATA_DEV(dev);
        
        fibril_mutex_lock(&e1000->ctrl_lock);
        
        uint32_t ctrl = E1000_REG_READ(e1000, E1000_CTRL);
        
        ctrl &= ~(CTRL_FRCSPD);
        ctrl &= ~(CTRL_FRCDPLX);
        ctrl |= CTRL_ASDE;
        
        E1000_REG_WRITE(e1000, E1000_CTRL, ctrl);
        
        fibril_mutex_unlock(&e1000->ctrl_lock);
        
        e1000_link_restart(e1000);
        
        return EOK;
}

/** Disable auto-negotiation
 *
 * @param dev Device to update
 *
 * @return EOK
 *
 */
static int e1000_autoneg_disable(ddf_fun_t *dev)
{
        e1000_t *e1000 = DRIVER_DATA_DEV(dev);
        
        fibril_mutex_lock(&e1000->ctrl_lock);
        
        uint32_t ctrl = E1000_REG_READ(e1000, E1000_CTRL);
        
        ctrl |= CTRL_FRCSPD;
        ctrl |= CTRL_FRCDPLX;
        ctrl &= ~(CTRL_ASDE);
        
        E1000_REG_WRITE(e1000, E1000_CTRL, ctrl);
        
        fibril_mutex_unlock(&e1000->ctrl_lock);
        
        e1000_link_restart(e1000);
        
        return EOK;
}

/** Restart auto-negotiation
 *
 * @param dev Device to update
 *
 * @return EOK if advertisement mode set successfully
 *
 */
static int e1000_autoneg_restart(ddf_fun_t *dev)
{
        return e1000_autoneg_enable(dev, 0);
}

/** Get state of acceptance of weird frames
 *
 * @param      device Device to check
 * @param[out] mode   Current mode
 *
 */
static int e1000_defective_get_mode(ddf_fun_t *device, uint32_t *mode)
{
        e1000_t *e1000 = DRIVER_DATA_DEV(device);
        
        *mode = 0;
        uint32_t rctl = E1000_REG_READ(e1000, E1000_RCTL);
        if (rctl & RCTL_SBP)
                *mode = NIC_DEFECTIVE_BAD_CRC | NIC_DEFECTIVE_SHORT;
        
        return EOK;
};

/** Set acceptance of weird frames
 *
 * @param device Device to update
 * @param mode   Mode to set
 *
 * @return ENOTSUP if the mode is not supported
 * @return EOK of mode was set
 *
 */
static int e1000_defective_set_mode(ddf_fun_t *device, uint32_t mode)
{
        e1000_t *e1000 = DRIVER_DATA_DEV(device);
        int rc = EOK;
        
        fibril_mutex_lock(&e1000->rx_lock);
        
        uint32_t rctl = E1000_REG_READ(e1000, E1000_RCTL);
        bool short_mode = (mode & NIC_DEFECTIVE_SHORT ? true : false);
        bool bad_mode = (mode & NIC_DEFECTIVE_BAD_CRC ? true : false);
        
        if (short_mode && bad_mode)
                rctl |= RCTL_SBP;
        else if ((!short_mode) && (!bad_mode))
                rctl &= ~RCTL_SBP;
        else
                rc = ENOTSUP;
        
        E1000_REG_WRITE(e1000, E1000_RCTL, rctl);
        
        fibril_mutex_unlock(&e1000->rx_lock);
        return rc;
};

/** Write receive address to RA registr
 *
 * @param e1000      E1000 data structure
 * @param position   RA register position
 * @param address    Ethernet address
 * @param set_av_bit Set the Addtess Valid bit
 *
 */
static void e1000_write_receive_address(e1000_t *e1000, unsigned int position,
    const nic_address_t * address, bool set_av_bit)
{
        uint8_t *mac0 = (uint8_t *) address->address;
        uint8_t *mac1 = (uint8_t *) address->address + 1;
        uint8_t *mac2 = (uint8_t *) address->address + 2;
        uint8_t *mac3 = (uint8_t *) address->address + 3;
        uint8_t *mac4 = (uint8_t *) address->address + 4;
        uint8_t *mac5 = (uint8_t *) address->address + 5;
        
        uint32_t rah;
        uint32_t ral;
        
        ral = ((*mac3) << 24) | ((*mac2) << 16) | ((*mac1) << 8) | (*mac0);
        rah = ((*mac5) << 8) | ((*mac4));
        
        if (set_av_bit)
                rah |= RAH_AV;
        else
                rah |= E1000_REG_READ(e1000, E1000_RAH_ARRAY(position)) & RAH_AV;
        
        E1000_REG_WRITE(e1000, E1000_RAH_ARRAY(position), rah);
        E1000_REG_WRITE(e1000, E1000_RAL_ARRAY(position), ral);
}

/** Disable receive address in RA registr
 *
 *  Clear Address Valid bit
 *
 * @param e1000    E1000 data structure
 * @param position RA register position
 *
 */
static void e1000_disable_receive_address(e1000_t *e1000, unsigned int position)
{
        uint32_t rah = E1000_REG_READ(e1000, E1000_RAH_ARRAY(position));
        rah = rah & ~RAH_AV;
        E1000_REG_WRITE(e1000, E1000_RAH_ARRAY(position), rah);
}

/** Clear all unicast addresses from RA registers
 *
 * @param e1000 E1000 data structure
 *
 */
static void e1000_clear_unicast_receive_addresses(e1000_t *e1000)
{
        for (unsigned int ra_num = 1;
            ra_num <= e1000->unicast_ra_count;
            ra_num++)
                e1000_disable_receive_address(e1000, ra_num);
        
        e1000->unicast_ra_count = 0;
}

/** Clear all multicast addresses from RA registers
 *
 * @param e1000 E1000 data structure
 *
 */
static void e1000_clear_multicast_receive_addresses(e1000_t *e1000)
{
        unsigned int first_multicast_ra_num =
            E1000_RECEIVE_ADDRESS - e1000->multicast_ra_count;
        
        for (unsigned int ra_num = E1000_RECEIVE_ADDRESS - 1;
            ra_num >= first_multicast_ra_num;
            ra_num--)
                e1000_disable_receive_address(e1000, ra_num);
        
        e1000->multicast_ra_count = 0;
}

/** Return receive address filter positions count usable for unicast
 *
 * @param e1000 E1000 data structure
 *
 * @return receive address filter positions count usable for unicast
 *
 */
static unsigned int get_free_unicast_address_count(e1000_t *e1000)
{
        return E1000_RECEIVE_ADDRESS - 1 - e1000->multicast_ra_count;
}

/** Return receive address filter positions count usable for multicast
 *
 * @param e1000 E1000 data structure
 *
 * @return receive address filter positions count usable for multicast
 *
 */
static unsigned int get_free_multicast_address_count(e1000_t *e1000)
{
        return E1000_RECEIVE_ADDRESS - 1 - e1000->unicast_ra_count;
}

/** Write unicast receive addresses to receive address filter registers
 *
 * @param e1000    E1000 data structure
 * @param addr     Pointer to address array
 * @param addr_cnt Address array count
 *
 */
static void e1000_add_unicast_receive_addresses(e1000_t *e1000,
    const nic_address_t *addr, size_t addr_cnt)
{
        assert(addr_cnt <= get_free_unicast_address_count(e1000));
        
        nic_address_t *addr_iterator = (nic_address_t *) addr;
        
        /* ra_num = 0 is primary address */
        for (unsigned int ra_num = 1;
            ra_num <= addr_cnt;
            ra_num++) {
                e1000_write_receive_address(e1000, ra_num, addr_iterator, true);
                addr_iterator++;
        }
}

/** Write multicast receive addresses to receive address filter registers
 *
 * @param e1000    E1000 data structure
 * @param addr     Pointer to address array
 * @param addr_cnt Address array count
 *
 */
static void e1000_add_multicast_receive_addresses(e1000_t *e1000,
    const nic_address_t *addr, size_t addr_cnt)
{
        assert(addr_cnt <= get_free_multicast_address_count(e1000));
        
        nic_address_t *addr_iterator = (nic_address_t *) addr;
        
        unsigned int first_multicast_ra_num = E1000_RECEIVE_ADDRESS - addr_cnt;
        for (unsigned int ra_num = E1000_RECEIVE_ADDRESS - 1;
            ra_num >= first_multicast_ra_num;
            ra_num--) {
                e1000_write_receive_address(e1000, ra_num, addr_iterator, true);
                addr_iterator++;
        }
}

/** Disable receiving frames for default address
 *
 * @param e1000 E1000 data structure
 *
 */
static void disable_ra0_address_filter(e1000_t *e1000)
{
        uint32_t rah0 = E1000_REG_READ(e1000, E1000_RAH_ARRAY(0));
        rah0 = rah0 & ~RAH_AV;
        E1000_REG_WRITE(e1000, E1000_RAH_ARRAY(0), rah0);
}

/** Enable receiving frames for default address
 *
 * @param e1000 E1000 data structure
 *
 */
static void enable_ra0_address_filter(e1000_t *e1000)
{
        uint32_t rah0 = E1000_REG_READ(e1000, E1000_RAH_ARRAY(0));
        rah0 = rah0 | RAH_AV;
        E1000_REG_WRITE(e1000, E1000_RAH_ARRAY(0), rah0);
}

/** Disable unicast promiscuous mode
 *
 * @param e1000 E1000 data structure
 *
 */
static void e1000_disable_unicast_promisc(e1000_t *e1000)
{
        uint32_t rctl = E1000_REG_READ(e1000, E1000_RCTL);
        rctl = rctl & ~RCTL_UPE;
        E1000_REG_WRITE(e1000, E1000_RCTL, rctl);
}

/** Enable unicast promiscuous mode
 *
 * @param e1000 E1000 data structure
 *
 */
static void e1000_enable_unicast_promisc(e1000_t *e1000)
{
        uint32_t rctl = E1000_REG_READ(e1000, E1000_RCTL);
        rctl = rctl | RCTL_UPE;
        E1000_REG_WRITE(e1000, E1000_RCTL, rctl);
}

/** Disable multicast promiscuous mode
 *
 * @param e1000 E1000 data structure
 *
 */
static void e1000_disable_multicast_promisc(e1000_t *e1000)
{
        uint32_t rctl = E1000_REG_READ(e1000, E1000_RCTL);
        rctl = rctl & ~RCTL_MPE;
        E1000_REG_WRITE(e1000, E1000_RCTL, rctl);
}

/** Enable multicast promiscuous mode
 *
 * @param e1000 E1000 data structure
 *
 */
static void e1000_enable_multicast_promisc(e1000_t *e1000)
{
        uint32_t rctl = E1000_REG_READ(e1000, E1000_RCTL);
        rctl = rctl | RCTL_MPE;
        E1000_REG_WRITE(e1000, E1000_RCTL, rctl);
}

/** Enable accepting of broadcast frames
 *
 * @param e1000 E1000 data structure
 *
 */
static void e1000_enable_broadcast_accept(e1000_t *e1000)
{
        uint32_t rctl = E1000_REG_READ(e1000, E1000_RCTL);
        rctl = rctl | RCTL_BAM;
        E1000_REG_WRITE(e1000, E1000_RCTL, rctl);
}

/** Disable accepting of broadcast frames
 *
 * @param e1000 E1000 data structure
 *
 */
static void e1000_disable_broadcast_accept(e1000_t *e1000)
{
        uint32_t rctl = E1000_REG_READ(e1000, E1000_RCTL);
        rctl = rctl & ~RCTL_BAM;
        E1000_REG_WRITE(e1000, E1000_RCTL, rctl);
}

/** Enable VLAN filtering according to VFTA registers
 *
 * @param e1000 E1000 data structure
 *
 */
static void e1000_enable_vlan_filter(e1000_t *e1000)
{
        uint32_t rctl = E1000_REG_READ(e1000, E1000_RCTL);
        rctl = rctl | RCTL_VFE;
        E1000_REG_WRITE(e1000, E1000_RCTL, rctl);
}

/** Disable VLAN filtering
 *
 * @param e1000 E1000 data structure
 *
 */
static void e1000_disable_vlan_filter(e1000_t *e1000)
{
        uint32_t rctl = E1000_REG_READ(e1000, E1000_RCTL);
        rctl = rctl & ~RCTL_VFE;
        E1000_REG_WRITE(e1000, E1000_RCTL, rctl);
}

/** Set multicast frames acceptance mode
 *
 * @param nic      NIC device to update
 * @param mode     Mode to set
 * @param addr     Address list (used in mode = NIC_MULTICAST_LIST)
 * @param addr_cnt Length of address list (used in mode = NIC_MULTICAST_LIST)
 *
 * @return EOK
 *
 */
static int e1000_on_multicast_mode_change(nic_t *nic, nic_multicast_mode_t mode,
    const nic_address_t *addr, size_t addr_cnt)
{
        e1000_t *e1000 = DRIVER_DATA_NIC(nic);
        int rc = EOK;
        
        fibril_mutex_lock(&e1000->rx_lock);
        
        switch (mode) {
        case NIC_MULTICAST_BLOCKED:
                e1000_clear_multicast_receive_addresses(e1000);
                e1000_disable_multicast_promisc(e1000);
                nic_report_hw_filtering(nic, -1, 1, -1);
                break;
        case NIC_MULTICAST_LIST:
                e1000_clear_multicast_receive_addresses(e1000);
                if (addr_cnt > get_free_multicast_address_count(e1000)) {
                        /*
                         * Future work: fill MTA table
                         * Not strictly neccessary, it only saves some compares
                         * in the NIC library.
                         */
                        e1000_enable_multicast_promisc(e1000);
                        nic_report_hw_filtering(nic, -1, 0, -1);
                } else {
                        e1000_disable_multicast_promisc(e1000);
                        e1000_add_multicast_receive_addresses(e1000, addr, addr_cnt);
                        nic_report_hw_filtering(nic, -1, 1, -1);
                }
                break;
        case NIC_MULTICAST_PROMISC:
                e1000_enable_multicast_promisc(e1000);
                e1000_clear_multicast_receive_addresses(e1000);
                nic_report_hw_filtering(nic, -1, 1, -1);
                break;
        default:
                rc = ENOTSUP;
                break;
        }
        
        fibril_mutex_unlock(&e1000->rx_lock);
        return rc;
}

/** Set unicast frames acceptance mode
 *
 * @param nic      NIC device to update
 * @param mode     Mode to set
 * @param addr     Address list (used in mode = NIC_MULTICAST_LIST)
 * @param addr_cnt Length of address list (used in mode = NIC_MULTICAST_LIST)
 *
 * @return EOK
 *
 */
static int e1000_on_unicast_mode_change(nic_t *nic, nic_unicast_mode_t mode,
    const nic_address_t *addr, size_t addr_cnt)
{
        e1000_t *e1000 = DRIVER_DATA_NIC(nic);
        int rc = EOK;
        
        fibril_mutex_lock(&e1000->rx_lock);
        
        switch (mode) {
        case NIC_UNICAST_BLOCKED:
                disable_ra0_address_filter(e1000);
                e1000_clear_unicast_receive_addresses(e1000);
                e1000_disable_unicast_promisc(e1000);
                nic_report_hw_filtering(nic, 1, -1, -1);
                break;
        case NIC_UNICAST_DEFAULT:
                enable_ra0_address_filter(e1000);
                e1000_clear_unicast_receive_addresses(e1000);
                e1000_disable_unicast_promisc(e1000);
                nic_report_hw_filtering(nic, 1, -1, -1);
                break;
        case NIC_UNICAST_LIST:
                enable_ra0_address_filter(e1000);
                e1000_clear_unicast_receive_addresses(e1000);
                if (addr_cnt > get_free_unicast_address_count(e1000)) {
                        e1000_enable_unicast_promisc(e1000);
                        nic_report_hw_filtering(nic, 0, -1, -1);
                } else {
                        e1000_disable_unicast_promisc(e1000);
                        e1000_add_unicast_receive_addresses(e1000, addr, addr_cnt);
                        nic_report_hw_filtering(nic, 1, -1, -1);
                }
                break;
        case NIC_UNICAST_PROMISC:
                e1000_enable_unicast_promisc(e1000);
                enable_ra0_address_filter(e1000);
                e1000_clear_unicast_receive_addresses(e1000);
                nic_report_hw_filtering(nic, 1, -1, -1);
                break;
        default:
                rc = ENOTSUP;
                break;
        }
        
        fibril_mutex_unlock(&e1000->rx_lock);
        return rc;
}

/** Set broadcast frames acceptance mode
 *
 * @param nic  NIC device to update
 * @param mode Mode to set
 *
 * @return EOK
 *
 */
static int e1000_on_broadcast_mode_change(nic_t *nic, nic_broadcast_mode_t mode)
{
        e1000_t *e1000 = DRIVER_DATA_NIC(nic);
        int rc = EOK;
        
        fibril_mutex_lock(&e1000->rx_lock);
        
        switch (mode) {
        case NIC_BROADCAST_BLOCKED:
                e1000_disable_broadcast_accept(e1000);
                break;
        case NIC_BROADCAST_ACCEPTED:
                e1000_enable_broadcast_accept(e1000);
                break;
        default:
                rc = ENOTSUP;
                break;
        }
        
        fibril_mutex_unlock(&e1000->rx_lock);
        return rc;
}

/** Check if receiving is enabled
 *
 * @param e1000 E1000 data structure
 *
 * @return true if receiving is enabled
 *
 */
static bool e1000_is_rx_enabled(e1000_t *e1000)
{
        if (E1000_REG_READ(e1000, E1000_RCTL) & (RCTL_EN))
                return true;
        
        return false;
}

/** Enable receiving
 *
 * @param e1000 E1000 data structure
 *
 */
static void e1000_enable_rx(e1000_t *e1000)
{
        /* Set Receive Enable Bit */
        E1000_REG_WRITE(e1000, E1000_RCTL,
            E1000_REG_READ(e1000, E1000_RCTL) | (RCTL_EN));
}

/** Disable receiving
 *
 * @param e1000 E1000 data structure
 *
 */
static void e1000_disable_rx(e1000_t *e1000)
{
        /* Clear Receive Enable Bit */
        E1000_REG_WRITE(e1000, E1000_RCTL,
            E1000_REG_READ(e1000, E1000_RCTL) & ~(RCTL_EN));
}

/** Set VLAN mask
 *
 * @param nic       NIC device to update
 * @param vlan_mask VLAN mask
 *
 */
static void e1000_on_vlan_mask_change(nic_t *nic,
    const nic_vlan_mask_t *vlan_mask)
{
        e1000_t *e1000 = DRIVER_DATA_NIC(nic);
        
        fibril_mutex_lock(&e1000->rx_lock);
        
        if (vlan_mask) {
                /*
                 * Disable receiving, so that frame matching
                 * partially written VLAN is not received.
                 */
                bool rx_enabled = e1000_is_rx_enabled(e1000);
                if (rx_enabled)
                        e1000_disable_rx(e1000);
                
                for (unsigned int i = 0; i < NIC_VLAN_BITMAP_SIZE; i += 4) {
                        uint32_t bitmap_part =
                            ((uint32_t) vlan_mask->bitmap[i]) |
                            (((uint32_t) vlan_mask->bitmap[i + 1]) << 8) |
                            (((uint32_t) vlan_mask->bitmap[i + 2]) << 16) |
                            (((uint32_t) vlan_mask->bitmap[i + 3]) << 24);
                        E1000_REG_WRITE(e1000, E1000_VFTA_ARRAY(i / 4), bitmap_part);
                }
                
                e1000_enable_vlan_filter(e1000);
                if (rx_enabled)
                        e1000_enable_rx(e1000);
        } else
                e1000_disable_vlan_filter(e1000);
        
        fibril_mutex_unlock(&e1000->rx_lock);
}

/** Set VLAN mask
 *
 * @param device E1000 device
 * @param tag    VLAN tag
 *
 * @return EOK
 * @return ENOTSUP
 *
 */
static int e1000_vlan_set_tag(ddf_fun_t *device, uint16_t tag, bool add,
    bool strip)
{
        /* VLAN CFI bit cannot be set */
        if (tag & VLANTAG_CFI)
                return ENOTSUP;
        
        /*
         * CTRL.VME is neccessary for both strip and add
         * but CTRL.VME means stripping tags on receive.
         */
        if (!strip && add)
                return ENOTSUP;
        
        e1000_t *e1000 = DRIVER_DATA_DEV(device);
        
        e1000->vlan_tag = tag;
        e1000->vlan_tag_add = add;
        
        fibril_mutex_lock(&e1000->ctrl_lock);
        
        uint32_t ctrl = E1000_REG_READ(e1000, E1000_CTRL);
        if (strip)
                ctrl |= CTRL_VME;
        else
                ctrl &= ~CTRL_VME;
        
        E1000_REG_WRITE(e1000, E1000_CTRL, ctrl);
        
        fibril_mutex_unlock(&e1000->ctrl_lock);
        return EOK;
}

/** Fill receive descriptor with new empty buffer
 *
 * Store frame in e1000->rx_frame_phys
 *
 * @param nic    NIC data stricture
 * @param offset Receive descriptor offset
 *
 */
static void e1000_fill_new_rx_descriptor(nic_t *nic, size_t offset)
{
        e1000_t *e1000 = DRIVER_DATA_NIC(nic);
        
        e1000_rx_descriptor_t *rx_descriptor = (e1000_rx_descriptor_t *)
            (e1000->rx_ring_virt + offset * sizeof(e1000_rx_descriptor_t));
        
        rx_descriptor->phys_addr = PTR_TO_U64(e1000->rx_frame_phys[offset]);
        rx_descriptor->length = 0;
        rx_descriptor->checksum = 0;
        rx_descriptor->status = 0;
        rx_descriptor->errors = 0;
        rx_descriptor->special = 0;
}

/** Clear receive descriptor
 *
 * @param e1000  E1000 data
 * @param offset Receive descriptor offset
 *
 */
static void e1000_clear_rx_descriptor(e1000_t *e1000, unsigned int offset)
{
        e1000_rx_descriptor_t *rx_descriptor = (e1000_rx_descriptor_t *)
            (e1000->rx_ring_virt + offset * sizeof(e1000_rx_descriptor_t));
        
        rx_descriptor->length = 0;
        rx_descriptor->checksum = 0;
        rx_descriptor->status = 0;
        rx_descriptor->errors = 0;
        rx_descriptor->special = 0;
}

/** Clear receive descriptor
 *
 * @param nic    NIC data
 * @param offset Receive descriptor offset
 *
 */
static void e1000_clear_tx_descriptor(nic_t *nic, unsigned int offset)
{
        e1000_t *e1000 = DRIVER_DATA_NIC(nic);
        
        e1000_tx_descriptor_t *tx_descriptor = (e1000_tx_descriptor_t *)
            (e1000->tx_ring_virt + offset * sizeof(e1000_tx_descriptor_t));
        
        tx_descriptor->phys_addr = 0;
        tx_descriptor->length = 0;
        tx_descriptor->checksum_offset = 0;
        tx_descriptor->command = 0;
        tx_descriptor->status = 0;
        tx_descriptor->checksum_start_field = 0;
        tx_descriptor->special = 0;
}

/** Increment tail pointer for receive or transmit ring
 *
 * @param tail              Old Tail
 * @param descriptors_count Ring length
 *
 * @return New tail
 *
 */
static uint32_t e1000_inc_tail(uint32_t tail, uint32_t descriptors_count)
{
        if (tail + 1 == descriptors_count)
                return 0;
        else
                return tail + 1;
}

/** Receive frames
 *
 * @param nic NIC data
 *
 */
static void e1000_receive_frames(nic_t *nic)
{
        e1000_t *e1000 = DRIVER_DATA_NIC(nic);
        
        fibril_mutex_lock(&e1000->rx_lock);
        
        uint32_t *tail_addr = E1000_REG_ADDR(e1000, E1000_RDT);
        uint32_t next_tail = e1000_inc_tail(*tail_addr, E1000_RX_FRAME_COUNT);
        
        e1000_rx_descriptor_t *rx_descriptor = (e1000_rx_descriptor_t *)
            (e1000->rx_ring_virt + next_tail * sizeof(e1000_rx_descriptor_t));
        
        while (rx_descriptor->status & 0x01) {
                uint32_t frame_size = rx_descriptor->length - E1000_CRC_SIZE;
                
                nic_frame_t *frame = nic_alloc_frame(nic, frame_size);
                if (frame != NULL) {
                        memcpy(frame->data, e1000->rx_frame_virt[next_tail], frame_size);
                        nic_received_frame(nic, frame);
                } else {
                        ddf_msg(LVL_ERROR, "Memory allocation failed. Frame dropped.");
                }
                
                e1000_fill_new_rx_descriptor(nic, next_tail);
                
                *tail_addr = e1000_inc_tail(*tail_addr, E1000_RX_FRAME_COUNT);
                next_tail = e1000_inc_tail(*tail_addr, E1000_RX_FRAME_COUNT);
                
                rx_descriptor = (e1000_rx_descriptor_t *)
                    (e1000->rx_ring_virt + next_tail * sizeof(e1000_rx_descriptor_t));
        }
        
        fibril_mutex_unlock(&e1000->rx_lock);
}

/** Enable E1000 interupts
 *
 * @param e1000 E1000 data structure
 *
 */
static void e1000_enable_interrupts(e1000_t *e1000)
{
        E1000_REG_WRITE(e1000, E1000_IMS, ICR_RXT0);
}

/** Disable E1000 interupts
 *
 * @param e1000 E1000 data structure
 *
 */
static void e1000_disable_interrupts(e1000_t *e1000)
{
        E1000_REG_WRITE(e1000, E1000_IMS, 0);
}

/** Interrupt handler implementation
 *
 * This function is called from e1000_interrupt_handler()
 * and e1000_poll()
 *
 * @param nic NIC data
 * @param icr ICR register value
 *
 */
static void e1000_interrupt_handler_impl(nic_t *nic, uint32_t icr)
{
        if (icr & ICR_RXT0)
                e1000_receive_frames(nic);
}

/** Handle device interrupt
 *
 * @param dev   E1000 device
 * @param iid   IPC call id
 * @param icall IPC call structure
 *
 */
static void e1000_interrupt_handler(ddf_dev_t *dev, ipc_callid_t iid,
    ipc_call_t *icall)
{
        uint32_t icr = (uint32_t) IPC_GET_ARG2(*icall);
        nic_t *nic = NIC_DATA_DEV(dev);
        e1000_t *e1000 = DRIVER_DATA_NIC(nic);
        
        e1000_interrupt_handler_impl(nic, icr);
        e1000_enable_interrupts(e1000);
}

/** Register interrupt handler for the card in the system
 *
 * Note: The global irq_reg_mutex is locked because of work with global
 * structure.
 *
 * @param nic Driver data
 *
 * @return EOK if the handler was registered
 * @return Negative error code otherwise
 *
 */
inline static int e1000_register_int_handler(nic_t *nic)
{
        e1000_t *e1000 = DRIVER_DATA_NIC(nic);
        
        /* Lock the mutex in whole driver while working with global structure */
        fibril_mutex_lock(&irq_reg_mutex);
        
        e1000_irq_code.cmds[0].addr = e1000->reg_base_virt + E1000_ICR;
        e1000_irq_code.cmds[2].addr = e1000->reg_base_virt + E1000_IMC;
        
        int rc = register_interrupt_handler(nic_get_ddf_dev(nic),
            e1000->irq, e1000_interrupt_handler, &e1000_irq_code);
        
        fibril_mutex_unlock(&irq_reg_mutex);
        return rc;
}

/** Force receiving all frames in the receive buffer
 *
 * @param nic NIC data
 *
 */
static void e1000_poll(nic_t *nic)
{
        assert(nic);
        
        e1000_t *e1000 = nic_get_specific(nic);
        assert(e1000);
        
        uint32_t icr = E1000_REG_READ(e1000, E1000_ICR);
        e1000_interrupt_handler_impl(nic, icr);
}

/** Calculates ITR register interrupt from timeval structure
 *
 * @param period Period
 *
 */
static uint16_t e1000_calculate_itr_interval(const struct timeval *period)
{
        // TODO: use also tv_sec
        return e1000_calculate_itr_interval_from_usecs(period->tv_usec);
}

/** Set polling mode
 *
 * @param device  Device to set
 * @param mode    Mode to set
 * @param period  Period for NIC_POLL_PERIODIC
 *
 * @return EOK if succeed
 * @return ENOTSUP if the mode is not supported
 *
 */
static int e1000_poll_mode_change(nic_t *nic, nic_poll_mode_t mode,
    const struct timeval *period)
{
        assert(nic);
        
        e1000_t *e1000 = nic_get_specific(nic);
        assert(e1000);
        
        switch (mode) {
        case NIC_POLL_IMMEDIATE:
                E1000_REG_WRITE(e1000, E1000_ITR, 0);
                e1000_enable_interrupts(e1000);
                break;
        case NIC_POLL_ON_DEMAND:
                e1000_disable_interrupts(e1000);
                break;
        case NIC_POLL_PERIODIC:
                assert(period);
                uint16_t itr_interval = e1000_calculate_itr_interval(period);
                E1000_REG_WRITE(e1000, E1000_ITR, (uint32_t) itr_interval);
                e1000_enable_interrupts(e1000);
                break;
        default:
                return ENOTSUP;
        }
        
        return EOK;
}

/** Initialize receive registers
 *
 * @param e1000 E1000 data structure
 *
 */
static void e1000_initialize_rx_registers(e1000_t *e1000)
{
        E1000_REG_WRITE(e1000, E1000_RDLEN, E1000_RX_FRAME_COUNT * 16);
        E1000_REG_WRITE(e1000, E1000_RDH, 0);
        
        /* It is not posible to let HW use all descriptors */
        E1000_REG_WRITE(e1000, E1000_RDT, E1000_RX_FRAME_COUNT - 1);
        
        /* Set Broadcast Enable Bit */
        E1000_REG_WRITE(e1000, E1000_RCTL, RCTL_BAM);
}

/** Initialize receive structure
 *
 * @param nic NIC data
 *
 * @return EOK if succeed
 * @return Negative error code otherwise
 *
 */
static int e1000_initialize_rx_structure(nic_t *nic)
{
        e1000_t *e1000 = DRIVER_DATA_NIC(nic);
        fibril_mutex_lock(&e1000->rx_lock);
        
        int rc = dmamem_map_anonymous(
            E1000_RX_FRAME_COUNT * sizeof(e1000_rx_descriptor_t),
            AS_AREA_READ | AS_AREA_WRITE, 0, &e1000->rx_ring_phys,
            &e1000->rx_ring_virt);
        if (rc != EOK)
                return rc;
        
        E1000_REG_WRITE(e1000, E1000_RDBAH,
            (uint32_t) (PTR_TO_U64(e1000->rx_ring_phys) >> 32));
        E1000_REG_WRITE(e1000, E1000_RDBAL,
            (uint32_t) PTR_TO_U64(e1000->rx_ring_phys));
        
        e1000->rx_frame_phys =
            calloc(E1000_RX_FRAME_COUNT, sizeof(void *));
        e1000->rx_frame_virt =
            calloc(E1000_RX_FRAME_COUNT, sizeof(void *));
        if (e1000->rx_frame_phys == NULL || e1000->rx_frame_virt == NULL) {
                rc = ENOMEM;
                goto error;
        }
        
        size_t i;
        void *frame_virt;
        void *frame_phys;
        
        for (i = 0; i < E1000_RX_FRAME_COUNT; i++) {
                rc = dmamem_map_anonymous(
                    E1000_MAX_SEND_FRAME_SIZE, AS_AREA_READ | AS_AREA_WRITE,
                    0, &frame_phys, &frame_virt);
                if (rc != EOK)
                        goto error;
                
                e1000->rx_frame_virt[i] = frame_virt;
                e1000->rx_frame_phys[i] = frame_phys;
        }
        
        /* Write descriptor */
        for (i = 0; i < E1000_RX_FRAME_COUNT; i++)
                e1000_fill_new_rx_descriptor(nic, i);
        
        e1000_initialize_rx_registers(e1000);
        
        fibril_mutex_unlock(&e1000->rx_lock);
        return EOK;
        
error:
        for (i = 0; i < E1000_RX_FRAME_COUNT; i++) {
                if (e1000->rx_frame_virt[i] != NULL) {
                        dmamem_unmap_anonymous(e1000->rx_frame_virt[i]);
                        e1000->rx_frame_virt[i] = NULL;
                        e1000->rx_frame_phys[i] = NULL;
                }
        }
        
        if (e1000->rx_frame_phys != NULL) {
                free(e1000->rx_frame_phys);
                e1000->rx_frame_phys = NULL;
        }
        
        if (e1000->rx_frame_virt != NULL) {
                free(e1000->rx_frame_virt);
                e1000->rx_frame_phys = NULL;
        }
        
        return rc;
}

/** Uninitialize receive structure
 *
 * @param nic NIC data
 *
 */
static void e1000_uninitialize_rx_structure(nic_t *nic)
{
        e1000_t *e1000 = DRIVER_DATA_NIC(nic);
        
        /* Write descriptor */
        for (unsigned int offset = 0; offset < E1000_RX_FRAME_COUNT; offset++) {
                dmamem_unmap_anonymous(e1000->rx_frame_virt[offset]);
                e1000->rx_frame_virt[offset] = NULL;
                e1000->rx_frame_phys[offset] = NULL;
        }
        
        free(e1000->rx_frame_virt);
        free(e1000->rx_frame_phys);
        e1000->rx_frame_virt = NULL;
        e1000->rx_frame_phys = NULL;
        dmamem_unmap_anonymous(e1000->rx_ring_virt);
}

/** Clear receive descriptor ring
 *
 * @param e1000 E1000 data
 *
 */
static void e1000_clear_rx_ring(e1000_t *e1000)
{
        /* Write descriptor */
        for (unsigned int offset = 0;
            offset < E1000_RX_FRAME_COUNT;
            offset++)
                e1000_clear_rx_descriptor(e1000, offset);
}

/** Initialize filters
 *
 * @param e1000 E1000 data
 *
 */
static void e1000_initialize_filters(e1000_t *e1000)
{
        /* Initialize address filter */
        e1000->unicast_ra_count = 0;
        e1000->multicast_ra_count = 0;
        e1000_clear_unicast_receive_addresses(e1000);
}

/** Initialize VLAN
 *
 * @param e1000 E1000 data
 *
 */
static void e1000_initialize_vlan(e1000_t *e1000)
{
        e1000->vlan_tag_add = false;
}

/** Fill MAC address from EEPROM to RA[0] register
 *
 * @param e1000 E1000 data
 *
 */
static void e1000_fill_mac_from_eeprom(e1000_t *e1000)
{
        /* MAC address from eeprom to RA[0] */
        nic_address_t address;
        e1000_eeprom_get_address(e1000, &address);
        e1000_write_receive_address(e1000, 0, &address, true);
}

/** Initialize other registers
 *
 * @param dev E1000 data.
 *
 * @return EOK if succeed
 * @return Negative error code otherwise
 *
 */
static void e1000_initialize_registers(e1000_t *e1000)
{
        E1000_REG_WRITE(e1000, E1000_ITR,
            e1000_calculate_itr_interval_from_usecs(
            E1000_DEFAULT_INTERRUPT_INTERVAL_USEC));
        E1000_REG_WRITE(e1000, E1000_FCAH, 0);
        E1000_REG_WRITE(e1000, E1000_FCAL, 0);
        E1000_REG_WRITE(e1000, E1000_FCT, 0);
        E1000_REG_WRITE(e1000, E1000_FCTTV, 0);
        E1000_REG_WRITE(e1000, E1000_VET, VET_VALUE);
        E1000_REG_WRITE(e1000, E1000_CTRL, CTRL_ASDE);
}

/** Initialize transmit registers
 *
 * @param e1000 E1000 data.
 *
 */
static void e1000_initialize_tx_registers(e1000_t *e1000)
{
        E1000_REG_WRITE(e1000, E1000_TDLEN, E1000_TX_FRAME_COUNT * 16);
        E1000_REG_WRITE(e1000, E1000_TDH, 0);
        E1000_REG_WRITE(e1000, E1000_TDT, 0);
        
        E1000_REG_WRITE(e1000, E1000_TIPG,
            10 << TIPG_IPGT_SHIFT |
            8 << TIPG_IPGR1_SHIFT |
            6 << TIPG_IPGR2_SHIFT);
        
        E1000_REG_WRITE(e1000, E1000_TCTL,
            0x0F << TCTL_CT_SHIFT /* Collision Threshold */ |
            0x40 << TCTL_COLD_SHIFT /* Collision Distance */ |
            TCTL_PSP /* Pad Short Packets */);
}

/** Initialize transmit structure
 *
 * @param e1000 E1000 data.
 *
 */
static int e1000_initialize_tx_structure(e1000_t *e1000)
{
        size_t i;
        
        fibril_mutex_lock(&e1000->tx_lock);
        
        e1000->tx_ring_phys = NULL;
        e1000->tx_ring_virt = NULL;
        e1000->tx_frame_phys = NULL;
        e1000->tx_frame_virt = NULL;
        
        int rc = dmamem_map_anonymous(
            E1000_TX_FRAME_COUNT * sizeof(e1000_tx_descriptor_t),
            AS_AREA_READ | AS_AREA_WRITE, 0, &e1000->tx_ring_phys,
            &e1000->tx_ring_virt);
        if (rc != EOK)
                goto error;
        
        bzero(e1000->tx_ring_virt,
            E1000_TX_FRAME_COUNT * sizeof(e1000_tx_descriptor_t));
        
        e1000->tx_frame_phys = calloc(E1000_TX_FRAME_COUNT, sizeof(void *));
        e1000->tx_frame_virt = calloc(E1000_TX_FRAME_COUNT, sizeof(void *));

        if (e1000->tx_frame_phys == NULL || e1000->tx_frame_virt == NULL) {
                rc = ENOMEM;
                goto error;
        }
        
        for (i = 0; i < E1000_TX_FRAME_COUNT; i++) {
                rc = dmamem_map_anonymous(
                    E1000_MAX_SEND_FRAME_SIZE, AS_AREA_READ | AS_AREA_WRITE,
                    0, &e1000->tx_frame_phys[i], &e1000->tx_frame_virt[i]);
                if (rc != EOK)
                        goto error;
        }
        
        E1000_REG_WRITE(e1000, E1000_TDBAH,
            (uint32_t) (PTR_TO_U64(e1000->tx_ring_phys) >> 32));
        E1000_REG_WRITE(e1000, E1000_TDBAL,
            (uint32_t) PTR_TO_U64(e1000->tx_ring_phys));
        
        e1000_initialize_tx_registers(e1000);
        
        fibril_mutex_unlock(&e1000->tx_lock);
        return EOK;
        
error:
        if (e1000->tx_ring_virt != NULL) {
                dmamem_unmap_anonymous(e1000->tx_ring_virt);
                e1000->tx_ring_virt = NULL;
        }
        
        if (e1000->tx_frame_phys != NULL && e1000->tx_frame_virt != NULL) {
                for (i = 0; i < E1000_TX_FRAME_COUNT; i++) {
                        if (e1000->tx_frame_virt[i] != NULL) {
                                dmamem_unmap_anonymous(e1000->tx_frame_virt[i]);
                                e1000->tx_frame_virt[i] = NULL;
                                e1000->tx_frame_phys[i] = NULL;
                        }
                }
        }
        
        if (e1000->tx_frame_phys != NULL) {
                free(e1000->tx_frame_phys);
                e1000->tx_frame_phys = NULL;
        }
        
        if (e1000->tx_frame_virt != NULL) {
                free(e1000->tx_frame_virt);
                e1000->tx_frame_phys = NULL;
        }
        
        return rc;
}

/** Uninitialize transmit structure
 *
 * @param nic NIC data
 *
 */
static void e1000_uninitialize_tx_structure(e1000_t *e1000)
{
        size_t i;
        
        for (i = 0; i < E1000_TX_FRAME_COUNT; i++) {
                dmamem_unmap_anonymous(e1000->tx_frame_virt[i]);
                e1000->tx_frame_virt[i] = NULL;
                e1000->tx_frame_phys[i] = NULL;
        }
        
        if (e1000->tx_frame_phys != NULL) {
                free(e1000->tx_frame_phys);
                e1000->tx_frame_phys = NULL;
        }
        
        if (e1000->tx_frame_virt != NULL) {
                free(e1000->tx_frame_virt);
                e1000->tx_frame_phys = NULL;
        }
        
        dmamem_unmap_anonymous(e1000->tx_ring_virt);
}

/** Clear transmit descriptor ring
 *
 * @param nic NIC data
 *
 */
static void e1000_clear_tx_ring(nic_t *nic)
{
        /* Write descriptor */
        for (unsigned int offset = 0;
            offset < E1000_TX_FRAME_COUNT;
            offset++)
                e1000_clear_tx_descriptor(nic, offset);
}

/** Enable transmit
 *
 * @param e1000 E1000 data
 *
 */
static void e1000_enable_tx(e1000_t *e1000)
{
        /* Set Transmit Enable Bit */
        E1000_REG_WRITE(e1000, E1000_TCTL,
            E1000_REG_READ(e1000, E1000_TCTL) | (TCTL_EN));
}

/** Disable transmit
 *
 * @param e1000 E1000 data
 *
 */
static void e1000_disable_tx(e1000_t *e1000)
{
        /* Clear Transmit Enable Bit */
        E1000_REG_WRITE(e1000, E1000_TCTL,
            E1000_REG_READ(e1000, E1000_TCTL) & ~(TCTL_EN));
}

/** Reset E1000 device
 *
 * @param e1000 The E1000 data
 *
 */
static int e1000_reset(nic_t *nic)
{
        e1000_t *e1000 = DRIVER_DATA_NIC(nic);
        
        E1000_REG_WRITE(e1000, E1000_CTRL, CTRL_RST);
        
        /* Wait for the reset */
        usleep(20);
        
        /* check if RST_BIT cleared */
        if (E1000_REG_READ(e1000, E1000_CTRL) & (CTRL_RST))
                return EINVAL;
        
        e1000_initialize_registers(e1000);
        e1000_initialize_rx_registers(e1000);
        e1000_initialize_tx_registers(e1000);
        e1000_fill_mac_from_eeprom(e1000);
        e1000_initialize_filters(e1000);
        e1000_initialize_vlan(e1000);
        
        return EOK;
}

/** Activate the device to receive and transmit frames
 *
 * @param nic NIC driver data
 *
 * @return EOK if activated successfully
 * @return Error code otherwise
 *
 */
static int e1000_on_activating(nic_t *nic)
{
        assert(nic);
        
        e1000_t *e1000 = DRIVER_DATA_NIC(nic);
        
        fibril_mutex_lock(&e1000->rx_lock);
        fibril_mutex_lock(&e1000->tx_lock);
        fibril_mutex_lock(&e1000->ctrl_lock);
        
        e1000_enable_interrupts(e1000);
        
        nic_enable_interrupt(nic, e1000->irq);
        
        e1000_clear_rx_ring(e1000);
        e1000_enable_rx(e1000);
        
        e1000_clear_tx_ring(nic);
        e1000_enable_tx(e1000);
        
        uint32_t ctrl = E1000_REG_READ(e1000, E1000_CTRL);
        ctrl |= CTRL_SLU;
        E1000_REG_WRITE(e1000, E1000_CTRL, ctrl);
        
        fibril_mutex_unlock(&e1000->ctrl_lock);
        fibril_mutex_unlock(&e1000->tx_lock);
        fibril_mutex_unlock(&e1000->rx_lock);
        
        return EOK;
}

/** Callback for NIC_STATE_DOWN change
 *
 * @param nic NIC driver data
 *
 * @return EOK if succeed
 * @return Error code otherwise
 *
 */
static int e1000_on_down_unlocked(nic_t *nic)
{
        e1000_t *e1000 = DRIVER_DATA_NIC(nic);
        
        uint32_t ctrl = E1000_REG_READ(e1000, E1000_CTRL);
        ctrl &= ~CTRL_SLU;
        E1000_REG_WRITE(e1000, E1000_CTRL, ctrl);
        
        e1000_disable_tx(e1000);
        e1000_disable_rx(e1000);
        
        nic_disable_interrupt(nic, e1000->irq);
        e1000_disable_interrupts(e1000);
        
        /*
         * Wait for the for the end of all data
         * transfers to descriptors.
         */
        usleep(100);
        
        return EOK;
}

/** Callback for NIC_STATE_DOWN change
 *
 * @param nic NIC driver data
 *
 * @return EOK if succeed
 * @return Error code otherwise
 *
 */
static int e1000_on_down(nic_t *nic)
{
        e1000_t *e1000 = DRIVER_DATA_NIC(nic);
        
        fibril_mutex_lock(&e1000->rx_lock);
        fibril_mutex_lock(&e1000->tx_lock);
        fibril_mutex_lock(&e1000->ctrl_lock);
        
        int rc = e1000_on_down_unlocked(nic);
        
        fibril_mutex_unlock(&e1000->ctrl_lock);
        fibril_mutex_unlock(&e1000->tx_lock);
        fibril_mutex_unlock(&e1000->rx_lock);
        
        return rc;
}

/** Callback for NIC_STATE_STOPPED change
 *
 * @param nic NIC driver data
 *
 * @return EOK if succeed
 * @return Error code otherwise
 *
 */
static int e1000_on_stopping(nic_t *nic)
{
        e1000_t *e1000 = DRIVER_DATA_NIC(nic);
        
        fibril_mutex_lock(&e1000->rx_lock);
        fibril_mutex_lock(&e1000->tx_lock);
        fibril_mutex_lock(&e1000->ctrl_lock);
        
        int rc = e1000_on_down_unlocked(nic);
        if (rc == EOK)
                rc = e1000_reset(nic);
        
        fibril_mutex_unlock(&e1000->ctrl_lock);
        fibril_mutex_unlock(&e1000->tx_lock);
        fibril_mutex_unlock(&e1000->rx_lock);
        
        return rc;
}

/** Create driver data structure
 *
 * @return Intialized device data structure or NULL
 *
 */
static e1000_t *e1000_create_dev_data(ddf_dev_t *dev)
{
        assert(dev);
        assert(!dev->driver_data);
        
        nic_t *nic = nic_create_and_bind(dev);
        if (!nic)
                return NULL;
        
        e1000_t *e1000 = malloc(sizeof(e1000_t));
        if (!e1000) {
                nic_unbind_and_destroy(dev);
                return NULL;
        }
        
        bzero(e1000, sizeof(e1000_t));
        
        nic_set_specific(nic, e1000);
        nic_set_send_frame_handler(nic, e1000_send_frame);
        nic_set_state_change_handlers(nic, e1000_on_activating,
            e1000_on_down, e1000_on_stopping);
        nic_set_filtering_change_handlers(nic,
            e1000_on_unicast_mode_change, e1000_on_multicast_mode_change,
            e1000_on_broadcast_mode_change, NULL, e1000_on_vlan_mask_change);
        nic_set_poll_handlers(nic, e1000_poll_mode_change, e1000_poll);
        
        fibril_mutex_initialize(&e1000->ctrl_lock);
        fibril_mutex_initialize(&e1000->rx_lock);
        fibril_mutex_initialize(&e1000->tx_lock);
        fibril_mutex_initialize(&e1000->eeprom_lock);
        
        return e1000;
}

/** Delete driver data structure
 *
 * @param data E1000 device data structure
 *
 */
inline static void e1000_delete_dev_data(ddf_dev_t *dev)
{
        assert(dev);
        
        if (dev->driver_data != NULL)
                nic_unbind_and_destroy(dev);
}

/** Clean up the E1000 device structure.
 *
 * @param dev Device structure.
 *
 */
static void e1000_dev_cleanup(ddf_dev_t *dev)
{
        assert(dev);
        
        e1000_delete_dev_data(dev);
        
        if (dev->parent_sess != NULL) {
                async_hangup(dev->parent_sess);
                dev->parent_sess = NULL;
        }
}

/** Fill the irq and io_addr part of device data structure
 *
 * The hw_resources must be obtained before calling this function
 *
 * @param dev          Device structure
 * @param hw_resources Hardware resources obtained from the parent device
 *
 * @return EOK if succeed
 * @return Negative error code otherwise
 *
 */
static int e1000_fill_resource_info(ddf_dev_t *dev,
    const hw_res_list_parsed_t *hw_resources)
{
        assert(dev != NULL);
        assert(hw_resources != NULL);
        assert(dev->driver_data != NULL);
        
        e1000_t *e1000 = DRIVER_DATA_DEV(dev);
        
        if (hw_resources->irqs.count != 1)
                return EINVAL;
        
        e1000->irq = hw_resources->irqs.irqs[0];
        e1000->reg_base_phys =
            MEMADDR_TO_PTR(hw_resources->mem_ranges.ranges[0].address);
        
        return EOK;
}

/** Obtain information about hardware resources of the device
 *
 * The device must be connected to the parent
 *
 * @param dev Device structure
 *
 * @return EOK if succeed
 * @return Negative error code otherwise
 *
 */
static int e1000_get_resource_info(ddf_dev_t *dev)
{
        assert(dev != NULL);
        assert(NIC_DATA_DEV(dev) != NULL);
        
        hw_res_list_parsed_t hw_res_parsed;
        hw_res_list_parsed_init(&hw_res_parsed);
        
        /* Get hw resources form parent driver */
        int rc = nic_get_resources(NIC_DATA_DEV(dev), &hw_res_parsed);
        if (rc != EOK)
                return rc;
        
        /* Fill resources information to the device */
        rc = e1000_fill_resource_info(dev, &hw_res_parsed);
        hw_res_list_parsed_clean(&hw_res_parsed);
        
        return rc;
}

/** Initialize the E1000 device structure
 *
 * @param dev Device information
 *
 * @return EOK if succeed
 * @return Negative error code otherwise
 *
 */
static int e1000_device_initialize(ddf_dev_t *dev)
{
        /* Allocate driver data for the device. */
        e1000_t *e1000 = e1000_create_dev_data(dev);
        if (e1000 == NULL) {
                ddf_msg(LVL_ERROR, "Unable to allocate device softstate");
                return ENOMEM;
        }
        
        /* Obtain and fill hardware resources info */
        int rc = e1000_get_resource_info(dev);
        if (rc != EOK) {
                ddf_msg(LVL_ERROR, "Cannot obtain hardware resources");
                e1000_dev_cleanup(dev);
                return rc;
        }
        
        uint16_t device_id;
        rc = pci_config_space_read_16(dev->parent_sess, PCI_DEVICE_ID,
            &device_id);
        if (rc != EOK) {
                ddf_msg(LVL_ERROR, "Cannot access PCI configuration space");
                e1000_dev_cleanup(dev);
                return rc;
        }
        
        e1000_board_t board;
        switch (device_id) {
        case 0x100e:
        case 0x1015:
        case 0x1016:
        case 0x1017:
                board = E1000_82540;
                break;
        case 0x1013:
        case 0x1018:
        case 0x1078:
                board = E1000_82541;
                break;
        case 0x1076:
        case 0x1077:
        case 0x107c:
                board = E1000_82541REV2;
                break;
        case 0x100f:
        case 0x1011:
        case 0x1026:
        case 0x1027:
        case 0x1028:
                board = E1000_82545;
                break;
        case 0x1010:
        case 0x1012:
        case 0x101d:
        case 0x1079:
        case 0x107a:
        case 0x107b:
                board = E1000_82546;
                break;
        case 0x1019:
        case 0x101a:
                board = E1000_82547;
                break;
        case 0x10b9:
                board = E1000_82572;
                break;
        case 0x1096:
                board = E1000_80003ES2;
                break;
        default:
                ddf_msg(LVL_ERROR, "Device not supported (%#" PRIx16 ")",
                    device_id);
                e1000_dev_cleanup(dev);
                return ENOTSUP;
        }
        
        switch (board) {
        case E1000_82540:
        case E1000_82541:
        case E1000_82541REV2:
        case E1000_82545:
        case E1000_82546:
                e1000->info.eerd_start = 0x01;
                e1000->info.eerd_done = 0x10;
                e1000->info.eerd_address_offset = 8;
                e1000->info.eerd_data_offset = 16;
                break;
        case E1000_82547:
        case E1000_82572:
        case E1000_80003ES2:
                e1000->info.eerd_start = 0x01;
                e1000->info.eerd_done = 0x02;
                e1000->info.eerd_address_offset = 2;
                e1000->info.eerd_data_offset = 16;
                break;
        }
        
        return EOK;
}

/** Enable the I/O ports of the device.
 *
 * @param dev E1000 device.
 *
 * @return EOK if successed
 * @return Negative error code otherwise
 *
 */
static int e1000_pio_enable(ddf_dev_t *dev)
{
        e1000_t *e1000 = DRIVER_DATA_DEV(dev);
        
        int rc = pio_enable(e1000->reg_base_phys, 8 * PAGE_SIZE,
            &e1000->reg_base_virt);
        if (rc != EOK)
                return EADDRNOTAVAIL;
        
        return EOK;
}

/** Probe and initialize the newly added device.
 *
 * @param dev E1000 device.
 *
 */
int e1000_dev_add(ddf_dev_t *dev)
{
        ddf_fun_t *fun;
        assert(dev);
        
        /* Initialize device structure for E1000 */
        int rc = e1000_device_initialize(dev);
        if (rc != EOK)
                return rc;
        
        /* Device initialization */
        nic_t *nic = dev->driver_data;
        e1000_t *e1000 = DRIVER_DATA_NIC(nic);
        
        /* Map registers */
        rc = e1000_pio_enable(dev);
        if (rc != EOK)
                goto err_destroy;
        
        e1000_initialize_registers(e1000);
        rc = e1000_initialize_tx_structure(e1000);
        if (rc != EOK)
                goto err_pio;
        
        fibril_mutex_lock(&e1000->rx_lock);
        
        e1000_fill_mac_from_eeprom(e1000);
        e1000_initialize_filters(e1000);
        
        fibril_mutex_unlock(&e1000->rx_lock);
        
        e1000_initialize_vlan(e1000);
        
        fun = ddf_fun_create(nic_get_ddf_dev(nic), fun_exposed, "port0");
        if (fun == NULL)
                goto err_tx_structure;
        nic_set_ddf_fun(nic, fun);
        fun->ops = &e1000_dev_ops;
        fun->driver_data = nic;
        
        rc = e1000_register_int_handler(nic);
        if (rc != EOK)
                goto err_fun_create;
        
        rc = nic_connect_to_services(nic);
        if (rc != EOK)
                goto err_irq;
        
        rc = e1000_initialize_rx_structure(nic);
        if (rc != EOK)
                goto err_irq;
        
        nic_address_t e1000_address;
        e1000_get_address(e1000, &e1000_address);
        rc = nic_report_address(nic, &e1000_address);
        if (rc != EOK)
                goto err_rx_structure;
        
        struct timeval period;
        period.tv_sec = 0;
        period.tv_usec = E1000_DEFAULT_INTERRUPT_INTERVAL_USEC;
        rc = nic_report_poll_mode(nic, NIC_POLL_PERIODIC, &period);
        if (rc != EOK)
                goto err_rx_structure;
        
        rc = ddf_fun_bind(fun);
        if (rc != EOK)
                goto err_fun_bind;
        
        rc = ddf_fun_add_to_category(fun, DEVICE_CATEGORY_NIC);
        if (rc != EOK)
                goto err_add_to_cat;
        
        return EOK;
        
err_add_to_cat:
        ddf_fun_unbind(fun);
err_fun_bind:
err_rx_structure:
        e1000_uninitialize_rx_structure(nic);
err_irq:
        unregister_interrupt_handler(dev, DRIVER_DATA_DEV(dev)->irq);
err_fun_create:
        ddf_fun_destroy(fun);
        nic_set_ddf_fun(nic, NULL);
err_tx_structure:
        e1000_uninitialize_tx_structure(e1000);
err_pio:
        // TODO: e1000_pio_disable(dev);
err_destroy:
        e1000_dev_cleanup(dev);
        return rc;
}

/** Read 16-bit value from EEPROM of E1000 adapter
 *
 * Read using the EERD register.
 *
 * @param device         E1000 device
 * @param eeprom_address 8-bit EEPROM address
 *
 * @return 16-bit value from EEPROM
 *
 */
static uint16_t e1000_eeprom_read(e1000_t *e1000, uint8_t eeprom_address)
{
        fibril_mutex_lock(&e1000->eeprom_lock);
        
        /* Write address and START bit to EERD register */
        uint32_t write_data = e1000->info.eerd_start |
            (((uint32_t) eeprom_address) <<
            e1000->info.eerd_address_offset);
        E1000_REG_WRITE(e1000, E1000_EERD, write_data);
        
        uint32_t eerd = E1000_REG_READ(e1000, E1000_EERD);
        while ((eerd & e1000->info.eerd_done) == 0) {
                usleep(1);
                eerd = E1000_REG_READ(e1000, E1000_EERD);
        }
        
        fibril_mutex_unlock(&e1000->eeprom_lock);
        
        return (uint16_t) (eerd >> e1000->info.eerd_data_offset);
}

/** Get MAC address of the E1000 adapter
 *
 * @param device  E1000 device
 * @param address Place to store the address
 * @param max_len Maximal addresss length to store
 *
 * @return EOK if succeed
 * @return Negative error code otherwise
 *
 */
static int e1000_get_address(e1000_t *e1000, nic_address_t *address)
{
        fibril_mutex_lock(&e1000->rx_lock);
        
        uint8_t *mac0_dest = (uint8_t *) address->address;
        uint8_t *mac1_dest = (uint8_t *) address->address + 1;
        uint8_t *mac2_dest = (uint8_t *) address->address + 2;
        uint8_t *mac3_dest = (uint8_t *) address->address + 3;
        uint8_t *mac4_dest = (uint8_t *) address->address + 4;
        uint8_t *mac5_dest = (uint8_t *) address->address + 5;
        
        uint32_t rah = E1000_REG_READ(e1000, E1000_RAH_ARRAY(0));
        uint32_t ral = E1000_REG_READ(e1000, E1000_RAL_ARRAY(0));
        
        *mac0_dest = (uint8_t) ral;
        *mac1_dest = (uint8_t) (ral >> 8);
        *mac2_dest = (uint8_t) (ral >> 16);
        *mac3_dest = (uint8_t) (ral >> 24);
        *mac4_dest = (uint8_t) rah;
        *mac5_dest = (uint8_t) (rah >> 8);
        
        fibril_mutex_unlock(&e1000->rx_lock);
        return EOK;
};

/** Set card MAC address
 *
 * @param device  E1000 device
 * @param address Address
 *
 * @return EOK if succeed
 * @return Negative error code otherwise
 */
static int e1000_set_addr(ddf_fun_t *dev, const nic_address_t *addr)
{
        nic_t *nic = NIC_DATA_DEV(dev);
        e1000_t *e1000 = DRIVER_DATA_NIC(nic);
        
        fibril_mutex_lock(&e1000->rx_lock);
        fibril_mutex_lock(&e1000->tx_lock);
        
        int rc = nic_report_address(nic, addr);
        if (rc == EOK)
                e1000_write_receive_address(e1000, 0, addr, false);
        
        fibril_mutex_unlock(&e1000->tx_lock);
        fibril_mutex_unlock(&e1000->rx_lock);
        
        return rc;
}

static void e1000_eeprom_get_address(e1000_t *e1000,
    nic_address_t *address)
{
        uint16_t *mac0_dest = (uint16_t *) address->address;
        uint16_t *mac2_dest = (uint16_t *) (address->address + 2);
        uint16_t *mac4_dest = (uint16_t *) (address->address + 4);
        
        *mac0_dest = e1000_eeprom_read(e1000, 0);
        *mac2_dest = e1000_eeprom_read(e1000, 1);
        *mac4_dest = e1000_eeprom_read(e1000, 2);
}

/** Send frame
 *
 * @param nic    NIC driver data structure
 * @param data   Frame data
 * @param size   Frame size in bytes
 *
 * @return EOK if succeed
 * @return Error code in the case of error
 *
 */
static void e1000_send_frame(nic_t *nic, void *data, size_t size)
{
        assert(nic);
        
        e1000_t *e1000 = DRIVER_DATA_NIC(nic);
        fibril_mutex_lock(&e1000->tx_lock);
        
        uint32_t tdt = E1000_REG_READ(e1000, E1000_TDT);
        e1000_tx_descriptor_t *tx_descriptor_addr = (e1000_tx_descriptor_t *)
            (e1000->tx_ring_virt + tdt * sizeof(e1000_tx_descriptor_t));
        
        bool descriptor_available = false;
        
        /* Descriptor never used */
        if (tx_descriptor_addr->length == 0)
                descriptor_available = true;
        
        /* Descriptor done */
        if (tx_descriptor_addr->status & TXDESCRIPTOR_STATUS_DD)
                descriptor_available = true;
        
        if (!descriptor_available) {
                /* Frame lost */
                fibril_mutex_unlock(&e1000->tx_lock);
                return;
        }
        
        memcpy(e1000->tx_frame_virt[tdt], data, size);
        
        tx_descriptor_addr->phys_addr = PTR_TO_U64(e1000->tx_frame_phys[tdt]);
        tx_descriptor_addr->length = size;
        
        /*
         * Report status to STATUS.DD (descriptor done),
         * add ethernet CRC, end of packet.
         */
        tx_descriptor_addr->command = TXDESCRIPTOR_COMMAND_RS |
            TXDESCRIPTOR_COMMAND_IFCS |
            TXDESCRIPTOR_COMMAND_EOP;
        
        tx_descriptor_addr->checksum_offset = 0;
        tx_descriptor_addr->status = 0;
        if (e1000->vlan_tag_add) {
                tx_descriptor_addr->special = e1000->vlan_tag;
                tx_descriptor_addr->command |= TXDESCRIPTOR_COMMAND_VLE;
        } else
                tx_descriptor_addr->special = 0;
        
        tx_descriptor_addr->checksum_start_field = 0;
        
        tdt++;
        if (tdt == E1000_TX_FRAME_COUNT)
                tdt = 0;
        
        E1000_REG_WRITE(e1000, E1000_TDT, tdt);
        
        fibril_mutex_unlock(&e1000->tx_lock);
}

int main(void)
{
        int rc = nic_driver_init(NAME);
        if (rc != EOK)
                return rc;
        
        nic_driver_implement(&e1000_driver_ops, &e1000_dev_ops,
            &e1000_nic_iface);
        
        ddf_log_init(NAME, LVL_ERROR);
        ddf_msg(LVL_NOTE, "HelenOS E1000 driver started");
        return ddf_driver_main(&e1000_driver);
}