/*      $NetBSD: if_axen.c,v 1.96 2023/12/19 08:19:42 skrll Exp $       */
/*      $OpenBSD: if_axen.c,v 1.3 2013/10/21 10:10:22 yuo Exp $ */

/*
 * Copyright (c) 2013 Yojiro UO <yuo@openbsd.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

/*
 * ASIX Electronics AX88178a USB 2.0 ethernet and AX88179 USB 3.0 Ethernet
 * driver.
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: if_axen.c,v 1.96 2023/12/19 08:19:42 skrll Exp $");

#ifdef _KERNEL_OPT
#include "opt_usb.h"
#endif

#include <sys/param.h>

#include <netinet/in.h>         /* XXX for netinet/ip.h */
#include <netinet/ip.h>         /* XXX for IP_MAXPACKET */

#include <dev/usb/usbnet.h>

#include <dev/usb/if_axenreg.h>

#ifdef AXEN_DEBUG
#define DPRINTF(x)      do { if (axendebug) printf x; } while (/*CONSTCOND*/0)
#define DPRINTFN(n, x)  do { if (axendebug >= (n)) printf x; } while (/*CONSTCOND*/0)
int     axendebug = 0;
#else
#define DPRINTF(x)
#define DPRINTFN(n, x)
#endif

struct axen_type {
        struct usb_devno        axen_devno;
        uint16_t                axen_flags;
#define AX178A  0x0001          /* AX88178a */
#define AX179   0x0002          /* AX88179 */
#define AX179A  0x0004          /* AX88179A */
};

/*
 * Various supported device vendors/products.
 */
static const struct axen_type axen_devs[] = {
#if 0 /* not tested */
        { { USB_VENDOR_ASIX, USB_PRODUCT_ASIX_AX88178A}, AX178A },
#endif
        { { USB_VENDOR_ASIX, USB_PRODUCT_ASIX_AX88179}, AX179 },
        { { USB_VENDOR_DLINK, USB_PRODUCT_DLINK_DUB1312}, AX179 }
};

#define axen_lookup(v, p) ((const struct axen_type *)usb_lookup(axen_devs, v, p))

static int      axen_match(device_t, cfdata_t, void *);
static void     axen_attach(device_t, device_t, void *);

CFATTACH_DECL_NEW(axen, sizeof(struct usbnet),
        axen_match, axen_attach, usbnet_detach, usbnet_activate);

static int      axen_cmd(struct usbnet *, int, int, int, void *);
static void     axen_reset(struct usbnet *);
static int      axen_get_eaddr(struct usbnet *, void *);
static void     axen_ax88179_init(struct usbnet *);

static void     axen_uno_stop(struct ifnet *, int);
static int      axen_uno_ioctl(struct ifnet *, u_long, void *);
static void     axen_uno_mcast(struct ifnet *);
static int      axen_uno_mii_read_reg(struct usbnet *, int, int, uint16_t *);
static int      axen_uno_mii_write_reg(struct usbnet *, int, int, uint16_t);
static void     axen_uno_mii_statchg(struct ifnet *);
static void     axen_uno_rx_loop(struct usbnet *, struct usbnet_chain *,
                                 uint32_t);
static unsigned axen_uno_tx_prepare(struct usbnet *, struct mbuf *,
                                    struct usbnet_chain *);
static int      axen_uno_init(struct ifnet *);

static const struct usbnet_ops axen_ops = {
        .uno_stop = axen_uno_stop,
        .uno_ioctl = axen_uno_ioctl,
        .uno_mcast = axen_uno_mcast,
        .uno_read_reg = axen_uno_mii_read_reg,
        .uno_write_reg = axen_uno_mii_write_reg,
        .uno_statchg = axen_uno_mii_statchg,
        .uno_tx_prepare = axen_uno_tx_prepare,
        .uno_rx_loop = axen_uno_rx_loop,
        .uno_init = axen_uno_init,
};

static int
axen_cmd(struct usbnet *un, int cmd, int index, int val, void *buf)
{
        usb_device_request_t req;
        usbd_status err;

        if (usbnet_isdying(un))
                return 0;

        if (AXEN_CMD_DIR(cmd))
                req.bmRequestType = UT_WRITE_VENDOR_DEVICE;
        else
                req.bmRequestType = UT_READ_VENDOR_DEVICE;
        req.bRequest = AXEN_CMD_CMD(cmd);
        USETW(req.wValue, val);
        USETW(req.wIndex, index);
        USETW(req.wLength, AXEN_CMD_LEN(cmd));

        err = usbd_do_request(un->un_udev, &req, buf);
        DPRINTFN(5, ("axen_cmd: cmd 0x%04x val 0x%04x len %d\n",
            cmd, val, AXEN_CMD_LEN(cmd)));

        if (err) {
                DPRINTF(("%s: cmd: %d, error: %d\n", __func__, cmd, err));
                return -1;
        }

        return 0;
}

static int
axen_uno_mii_read_reg(struct usbnet *un, int phy, int reg, uint16_t *val)
{
        uint16_t data;

        if (un->un_phyno != phy) {
                *val = 0;
                return EINVAL;
        }

        usbd_status err = axen_cmd(un, AXEN_CMD_MII_READ_REG, reg, phy, &data);
        if (err) {
                *val = 0;
                return EIO;
        }

        *val = le16toh(data);
        if (reg == MII_BMSR)
                *val &= ~BMSR_EXTCAP;

        return 0;
}

static int
axen_uno_mii_write_reg(struct usbnet *un, int phy, int reg, uint16_t val)
{
        uint16_t uval = htole16(val);

        if (un->un_phyno != phy)
                return EINVAL;

        usbd_status err = axen_cmd(un, AXEN_CMD_MII_WRITE_REG, reg, phy, &uval);
        if (err)
                return EIO;

        return 0;
}

static void
axen_uno_mii_statchg(struct ifnet *ifp)
{
        struct usbnet * const un = ifp->if_softc;
        struct mii_data * const mii = usbnet_mii(un);
        int err;
        uint16_t val;
        uint16_t wval;

        if (usbnet_isdying(un))
                return;

        if ((mii->mii_media_status & (IFM_ACTIVE | IFM_AVALID)) ==
            (IFM_ACTIVE | IFM_AVALID)) {
                switch (IFM_SUBTYPE(mii->mii_media_active)) {
                case IFM_10_T:
                case IFM_100_TX:
                        usbnet_set_link(un, true);
                        break;
                case IFM_1000_T:
                        usbnet_set_link(un, true);
                        break;
                default:
                        break;
                }
        }

        /* Lost link, do nothing. */
        if (!usbnet_havelink(un))
                return;

        val = 0;
        if ((mii->mii_media_active & IFM_FDX) != 0)
                val |= AXEN_MEDIUM_FDX;

        val |= AXEN_MEDIUM_RXFLOW_CTRL_EN | AXEN_MEDIUM_TXFLOW_CTRL_EN |
            AXEN_MEDIUM_RECV_EN;
        switch (IFM_SUBTYPE(mii->mii_media_active)) {
        case IFM_1000_T:
                val |= AXEN_MEDIUM_GIGA | AXEN_MEDIUM_EN_125MHZ;
                break;
        case IFM_100_TX:
                val |= AXEN_MEDIUM_PS;
                break;
        case IFM_10_T:
                /* doesn't need to be handled */
                break;
        }

        DPRINTF(("%s: val=%#x\n", __func__, val));
        wval = htole16(val);
        err = axen_cmd(un, AXEN_CMD_MAC_WRITE2, 2, AXEN_MEDIUM_STATUS, &wval);
        if (err)
                aprint_error_dev(un->un_dev, "media change failed\n");
}

static void
axen_uno_mcast(struct ifnet *ifp)
{
        struct usbnet * const un = ifp->if_softc;
        struct ethercom *ec = usbnet_ec(un);
        struct ether_multi *enm;
        struct ether_multistep step;
        uint32_t h = 0;
        uint16_t rxmode;
        uint8_t hashtbl[8] = { 0, 0, 0, 0, 0, 0, 0, 0 };
        uint16_t wval;

        if (usbnet_isdying(un))
                return;

        rxmode = 0;

        /* Enable receiver, set RX mode */
        axen_cmd(un, AXEN_CMD_MAC_READ2, 2, AXEN_MAC_RXCTL, &wval);
        rxmode = le16toh(wval);
        rxmode &= ~(AXEN_RXCTL_ACPT_ALL_MCAST | AXEN_RXCTL_PROMISC |
            AXEN_RXCTL_ACPT_MCAST);

        if (usbnet_ispromisc(un)) {
                DPRINTF(("%s: promisc\n", device_xname(un->un_dev)));
                rxmode |= AXEN_RXCTL_PROMISC;
allmulti:
                ETHER_LOCK(ec);
                ec->ec_flags |= ETHER_F_ALLMULTI;
                ETHER_UNLOCK(ec);
                rxmode |= AXEN_RXCTL_ACPT_ALL_MCAST
                /* | AXEN_RXCTL_ACPT_PHY_MCAST */;
        } else {
                /* now program new ones */
                DPRINTF(("%s: initializing hash table\n",
                    device_xname(un->un_dev)));
                ETHER_LOCK(ec);
                ec->ec_flags &= ~ETHER_F_ALLMULTI;

                ETHER_FIRST_MULTI(step, ec, enm);
                while (enm != NULL) {
                        if (memcmp(enm->enm_addrlo, enm->enm_addrhi,
                            ETHER_ADDR_LEN)) {
                                DPRINTF(("%s: allmulti\n",
                                    device_xname(un->un_dev)));
                                memset(hashtbl, 0, sizeof(hashtbl));
                                ETHER_UNLOCK(ec);
                                goto allmulti;
                        }
                        h = ether_crc32_be(enm->enm_addrlo,
                            ETHER_ADDR_LEN) >> 26;
                        hashtbl[h / 8] |= 1 << (h % 8);
                        DPRINTF(("%s: %s added\n",
                            device_xname(un->un_dev),
                            ether_sprintf(enm->enm_addrlo)));
                        ETHER_NEXT_MULTI(step, enm);
                }
                ETHER_UNLOCK(ec);
                rxmode |= AXEN_RXCTL_ACPT_MCAST;
        }

        axen_cmd(un, AXEN_CMD_MAC_WRITE_FILTER, 8, AXEN_FILTER_MULTI, hashtbl);
        wval = htole16(rxmode);
        axen_cmd(un, AXEN_CMD_MAC_WRITE2, 2, AXEN_MAC_RXCTL, &wval);
}

static void
axen_reset(struct usbnet *un)
{
        if (usbnet_isdying(un))
                return;
        /* XXX What to reset? */

        /* Wait a little while for the chip to get its brains in order. */
        DELAY(1000);
}

static int
axen_get_eaddr(struct usbnet *un, void *addr)
{
#if 1
        return axen_cmd(un, AXEN_CMD_MAC_READ_ETHER, 6, AXEN_CMD_MAC_NODE_ID,
            addr);
#else
        int i, retry;
        uint8_t eeprom[20];
        uint16_t csum;
        uint16_t buf;

        for (i = 0; i < 6; i++) {
                /* set eeprom address */
                buf = htole16(i);
                axen_cmd(un, AXEN_CMD_MAC_WRITE, 1, AXEN_MAC_EEPROM_ADDR, &buf);

                /* set eeprom command */
                buf = htole16(AXEN_EEPROM_READ);
                axen_cmd(un, AXEN_CMD_MAC_WRITE, 1, AXEN_MAC_EEPROM_CMD, &buf);

                /* check the value is ready */
                retry = 3;
                do {
                        buf = htole16(AXEN_EEPROM_READ);
                        usbd_delay_ms(un->un_udev, 10);
                        axen_cmd(un, AXEN_CMD_MAC_READ, 1, AXEN_MAC_EEPROM_CMD,
                            &buf);
                        retry--;
                        if (retry < 0)
                                return EINVAL;
                } while ((le16toh(buf) & 0xff) & AXEN_EEPROM_BUSY);

                /* read data */
                axen_cmd(un, AXEN_CMD_MAC_READ2, 2, AXEN_EEPROM_READ,
                    &eeprom[i * 2]);

                /* sanity check */
                if ((i == 0) && (eeprom[0] == 0xff))
                        return EINVAL;
        }

        /* check checksum */
        csum = eeprom[6] + eeprom[7] + eeprom[8] + eeprom[9];
        csum = (csum >> 8) + (csum & 0xff) + eeprom[10];
        if (csum != 0xff) {
                printf("eeprom checksum mismatch(0x%02x)\n", csum);
                return EINVAL;
        }

        memcpy(addr, eeprom, ETHER_ADDR_LEN);
        return 0;
#endif
}

static void
axen_ax88179_init(struct usbnet *un)
{
        struct axen_qctrl qctrl;
        uint16_t ctl, temp;
        uint16_t wval;
        uint8_t val;

        /* XXX: ? */
        axen_cmd(un, AXEN_CMD_MAC_READ, 1, AXEN_UNK_05, &val);
        DPRINTFN(5, ("AXEN_CMD_MAC_READ(0x05): 0x%02x\n", val));

        /* check AX88179 version, UA1 / UA2 */
        axen_cmd(un, AXEN_CMD_MAC_READ, 1, AXEN_GENERAL_STATUS, &val);
        /* UA1 */
        if (!(val & AXEN_GENERAL_STATUS_MASK)) {
                DPRINTF(("AX88179 ver. UA1\n"));
        } else {
                DPRINTF(("AX88179 ver. UA2\n"));
        }

        /* power up ethernet PHY */
        wval = htole16(0);
        axen_cmd(un, AXEN_CMD_MAC_WRITE2, 2, AXEN_PHYPWR_RSTCTL, &wval);

        wval = htole16(AXEN_PHYPWR_RSTCTL_IPRL);
        axen_cmd(un, AXEN_CMD_MAC_WRITE2, 2, AXEN_PHYPWR_RSTCTL, &wval);
        usbd_delay_ms(un->un_udev, 200);

        /* set clock mode */
        val = AXEN_PHYCLK_ACS | AXEN_PHYCLK_BCS;
        axen_cmd(un, AXEN_CMD_MAC_WRITE, 1, AXEN_PHYCLK, &val);
        usbd_delay_ms(un->un_udev, 100);

        /* set monitor mode (disable) */
        val = AXEN_MONITOR_NONE;
        axen_cmd(un, AXEN_CMD_MAC_WRITE, 1, AXEN_MONITOR_MODE, &val);

        /* enable auto detach */
        axen_cmd(un, AXEN_CMD_EEPROM_READ, 2, AXEN_EEPROM_STAT, &wval);
        temp = le16toh(wval);
        DPRINTFN(2,("EEPROM0x43 = 0x%04x\n", temp));
        if (!(temp == 0xffff) && !(temp & 0x0100)) {
                /* Enable auto detach bit */
                val = 0;
                axen_cmd(un, AXEN_CMD_MAC_WRITE, 1, AXEN_PHYCLK, &val);
                val = AXEN_PHYCLK_ULR;
                axen_cmd(un, AXEN_CMD_MAC_WRITE, 1, AXEN_PHYCLK, &val);
                usbd_delay_ms(un->un_udev, 100);

                axen_cmd(un, AXEN_CMD_MAC_READ2, 2, AXEN_PHYPWR_RSTCTL, &wval);
                ctl = le16toh(wval);
                ctl |= AXEN_PHYPWR_RSTCTL_AUTODETACH;
                wval = htole16(ctl);
                axen_cmd(un, AXEN_CMD_MAC_WRITE2, 2, AXEN_PHYPWR_RSTCTL, &wval);
                usbd_delay_ms(un->un_udev, 200);
                aprint_error_dev(un->un_dev, "enable auto detach (0x%04x)\n",
                    ctl);
        }

        /* bulkin queue setting */
        axen_cmd(un, AXEN_CMD_MAC_READ, 1, AXEN_USB_UPLINK, &val);
        switch (val) {
        case AXEN_USB_FS:
                DPRINTF(("uplink: USB1.1\n"));
                qctrl.ctrl       = 0x07;
                qctrl.timer_low  = 0xcc;
                qctrl.timer_high = 0x4c;
                qctrl.bufsize    = AXEN_BUFSZ_LS - 1;
                qctrl.ifg        = 0x08;
                break;
        case AXEN_USB_HS:
                DPRINTF(("uplink: USB2.0\n"));
                qctrl.ctrl       = 0x07;
                qctrl.timer_low  = 0x02;
                qctrl.timer_high = 0xa0;
                qctrl.bufsize    = AXEN_BUFSZ_HS - 1;
                qctrl.ifg        = 0xff;
                break;
        case AXEN_USB_SS:
                DPRINTF(("uplink: USB3.0\n"));
                qctrl.ctrl       = 0x07;
                qctrl.timer_low  = 0x4f;
                qctrl.timer_high = 0x00;
                qctrl.bufsize    = AXEN_BUFSZ_SS - 1;
                qctrl.ifg        = 0xff;
                break;
        default:
                aprint_error_dev(un->un_dev, "unknown uplink bus:0x%02x\n",
                    val);
                return;
        }
        axen_cmd(un, AXEN_CMD_MAC_SET_RXSR, 5, AXEN_RX_BULKIN_QCTRL, &qctrl);

        /*
         * set buffer high/low watermark to pause/resume.
         * write 2byte will set high/log simultaneous with AXEN_PAUSE_HIGH.
         * XXX: what is the best value? OSX driver uses 0x3c-0x4c as LOW-HIGH
         * watermark parameters.
         */
        val = 0x34;
        axen_cmd(un, AXEN_CMD_MAC_WRITE, 1, AXEN_PAUSE_LOW_WATERMARK, &val);
        val = 0x52;
        axen_cmd(un, AXEN_CMD_MAC_WRITE, 1, AXEN_PAUSE_HIGH_WATERMARK, &val);

        /* Set RX/TX configuration. */
        /* Set RX control register */
        ctl = AXEN_RXCTL_IPE | AXEN_RXCTL_DROPCRCERR | AXEN_RXCTL_AUTOB;
        wval = htole16(ctl);
        axen_cmd(un, AXEN_CMD_MAC_WRITE2, 2, AXEN_MAC_RXCTL, &wval);

        /* set monitor mode (enable) */
        val = AXEN_MONITOR_PMETYPE | AXEN_MONITOR_PMEPOL | AXEN_MONITOR_RWMP;
        axen_cmd(un, AXEN_CMD_MAC_WRITE, 1, AXEN_MONITOR_MODE, &val);
        axen_cmd(un, AXEN_CMD_MAC_READ, 1, AXEN_MONITOR_MODE, &val);
        DPRINTF(("axen: Monitor mode = 0x%02x\n", val));

        /* set medium type */
        ctl = AXEN_MEDIUM_GIGA | AXEN_MEDIUM_FDX | AXEN_MEDIUM_EN_125MHZ |
            AXEN_MEDIUM_RXFLOW_CTRL_EN | AXEN_MEDIUM_TXFLOW_CTRL_EN |
            AXEN_MEDIUM_RECV_EN;
        wval = htole16(ctl);
        DPRINTF(("axen: set to medium mode: 0x%04x\n", ctl));
        axen_cmd(un, AXEN_CMD_MAC_WRITE2, 2, AXEN_MEDIUM_STATUS, &wval);
        usbd_delay_ms(un->un_udev, 100);

        axen_cmd(un, AXEN_CMD_MAC_READ2, 2, AXEN_MEDIUM_STATUS, &wval);
        DPRINTF(("axen: current medium mode: 0x%04x\n", le16toh(wval)));

#if 0 /* XXX: TBD.... */
#define GMII_LED_ACTIVE         0x1a
#define GMII_PHY_PAGE_SEL       0x1e
#define GMII_PHY_PAGE_SEL       0x1f
#define GMII_PAGE_EXT           0x0007
        axen_uno_mii_write_reg(un, un->un_phyno, GMII_PHY_PAGE_SEL,
            GMII_PAGE_EXT);
        axen_uno_mii_write_reg(un, un->un_phyno, GMII_PHY_PAGE,
            0x002c);
#endif

#if 1 /* XXX: phy hack ? */
        axen_uno_mii_write_reg(un, un->un_phyno, 0x1F, 0x0005);
        axen_uno_mii_write_reg(un, un->un_phyno, 0x0C, 0x0000);
        axen_uno_mii_read_reg(un, un->un_phyno, 0x0001, &wval);
        axen_uno_mii_write_reg(un, un->un_phyno, 0x01, wval | 0x0080);
        axen_uno_mii_write_reg(un, un->un_phyno, 0x1F, 0x0000);
#endif
}

static void
axen_setoe_locked(struct usbnet *un)
{
        struct ifnet * const ifp = usbnet_ifp(un);
        uint64_t enabled = ifp->if_capenable;
        uint8_t val;

        KASSERT(IFNET_LOCKED(ifp));

        val = AXEN_RXCOE_OFF;
        if (enabled & IFCAP_CSUM_IPv4_Rx)
                val |= AXEN_RXCOE_IPv4;
        if (enabled & IFCAP_CSUM_TCPv4_Rx)
                val |= AXEN_RXCOE_TCPv4;
        if (enabled & IFCAP_CSUM_UDPv4_Rx)
                val |= AXEN_RXCOE_UDPv4;
        if (enabled & IFCAP_CSUM_TCPv6_Rx)
                val |= AXEN_RXCOE_TCPv6;
        if (enabled & IFCAP_CSUM_UDPv6_Rx)
                val |= AXEN_RXCOE_UDPv6;
        axen_cmd(un, AXEN_CMD_MAC_WRITE, 1, AXEN_RX_COE, &val);

        val = AXEN_TXCOE_OFF;
        if (enabled & IFCAP_CSUM_IPv4_Tx)
                val |= AXEN_TXCOE_IPv4;
        if (enabled & IFCAP_CSUM_TCPv4_Tx)
                val |= AXEN_TXCOE_TCPv4;
        if (enabled & IFCAP_CSUM_UDPv4_Tx)
                val |= AXEN_TXCOE_UDPv4;
        if (enabled & IFCAP_CSUM_TCPv6_Tx)
                val |= AXEN_TXCOE_TCPv6;
        if (enabled & IFCAP_CSUM_UDPv6_Tx)
                val |= AXEN_TXCOE_UDPv6;
        axen_cmd(un, AXEN_CMD_MAC_WRITE, 1, AXEN_TX_COE, &val);
}

static int
axen_uno_ioctl(struct ifnet *ifp, u_long cmd, void *data)
{
        struct usbnet * const un = ifp->if_softc;

        switch (cmd) {
        case SIOCSIFCAP:
                axen_setoe_locked(un);
                break;
        default:
                break;
        }

        return 0;
}

static int
axen_match(device_t parent, cfdata_t match, void *aux)
{
        struct usb_attach_arg *uaa = aux;

        return axen_lookup(uaa->uaa_vendor, uaa->uaa_product) != NULL ?
                UMATCH_VENDOR_PRODUCT : UMATCH_NONE;
}

static void
axen_attach(device_t parent, device_t self, void *aux)
{
        USBNET_MII_DECL_DEFAULT(unm);
        struct usbnet * const un = device_private(self);
        struct usb_attach_arg *uaa = aux;
        struct usbd_device *dev = uaa->uaa_device;
        usbd_status err;
        usb_interface_descriptor_t *id;
        usb_endpoint_descriptor_t *ed;
        char *devinfop;
        int i;

        aprint_naive("\n");
        aprint_normal("\n");
        devinfop = usbd_devinfo_alloc(dev, 0);
        aprint_normal_dev(self, "%s\n", devinfop);
        usbd_devinfo_free(devinfop);

        un->un_dev = self;
        un->un_udev = dev;
        un->un_sc = un;
        un->un_ops = &axen_ops;
        un->un_rx_xfer_flags = USBD_SHORT_XFER_OK;
        un->un_tx_xfer_flags = USBD_FORCE_SHORT_XFER;
        un->un_rx_list_cnt = AXEN_RX_LIST_CNT;
        un->un_tx_list_cnt = AXEN_TX_LIST_CNT;

        err = usbd_set_config_no(dev, AXEN_CONFIG_NO, 1);
        if (err) {
                aprint_error_dev(self, "failed to set configuration"
                    ", err=%s\n", usbd_errstr(err));
                return;
        }

        un->un_flags =
            axen_lookup(uaa->uaa_vendor, uaa->uaa_product)->axen_flags;
        if (UGETW(usbd_get_device_descriptor(dev)->bcdDevice) == 0x0200) {
                un->un_flags &= ~(AX178A | AX179);
                un->un_flags |= AX179A;
        }

        err = usbd_device2interface_handle(dev, AXEN_IFACE_IDX, &un->un_iface);
        if (err) {
                aprint_error_dev(self, "getting interface handle failed\n");
                return;
        }

        /* decide on what our bufsize will be */
        switch (dev->ud_speed) {
        case USB_SPEED_SUPER:
                un->un_rx_bufsz = AXEN_BUFSZ_SS * 1024;
                break;
        case USB_SPEED_HIGH:
                un->un_rx_bufsz = AXEN_BUFSZ_HS * 1024;
                break;
        default:
                un->un_rx_bufsz = AXEN_BUFSZ_LS * 1024;
                break;
        }
        un->un_tx_bufsz = IP_MAXPACKET + ETHER_HDR_LEN + ETHER_CRC_LEN +
            ETHER_VLAN_ENCAP_LEN + sizeof(struct axen_sframe_hdr);

        /* Find endpoints. */
        id = usbd_get_interface_descriptor(un->un_iface);
        for (i = 0; i < id->bNumEndpoints; i++) {
                ed = usbd_interface2endpoint_descriptor(un->un_iface, i);
                if (!ed) {
                        aprint_error_dev(self, "couldn't get ep %d\n", i);
                        return;
                }
                if (UE_GET_DIR(ed->bEndpointAddress) == UE_DIR_IN &&
                    UE_GET_XFERTYPE(ed->bmAttributes) == UE_BULK) {
                        un->un_ed[USBNET_ENDPT_RX] = ed->bEndpointAddress;
                } else if (UE_GET_DIR(ed->bEndpointAddress) == UE_DIR_OUT &&
                           UE_GET_XFERTYPE(ed->bmAttributes) == UE_BULK) {
                        un->un_ed[USBNET_ENDPT_TX] = ed->bEndpointAddress;
#if 0 /* not used yet */
                } else if (UE_GET_DIR(ed->bEndpointAddress) == UE_DIR_IN &&
                           UE_GET_XFERTYPE(ed->bmAttributes) == UE_INTERRUPT) {
                        un->un_ed[USBNET_ENDPT_INTR] = ed->bEndpointAddress;
#endif
                }
        }

        /* Set these up now for axen_cmd().  */
        usbnet_attach(un);

        un->un_phyno = AXEN_PHY_ID;
        DPRINTF(("%s: phyno %d\n", device_xname(self), un->un_phyno));

        /* Get station address.  */
        if (axen_get_eaddr(un, &un->un_eaddr)) {
                printf("EEPROM checksum error\n");
                return;
        }

        axen_ax88179_init(un);

#if 0
#define   AXEN_FW_MODE                          0x08
#define     AXEN_FW_MODE_178A179                0x0000
#define     AXEN_FW_MODE_179A                   0x0001
        if (un->un_flags & AX179A) {
                uint8_t bval = 0;
                /*          len         dir       cmd */
                int cmd = (1 << 12) | (1 << 8) | (AXEN_FW_MODE & 0x00FF);
                axen_cmd(un, cmd, 1, AXEN_FW_MODE_178A179, &bval);
        }
#endif

        /* An ASIX chip was detected. Inform the world.  */
        if (un->un_flags & AX178A)
                aprint_normal_dev(self, "AX88178a\n");
        else if (un->un_flags & AX179)
                aprint_normal_dev(self, "AX88179\n");
        else if (un->un_flags & AX179A)
                aprint_normal_dev(self, "AX88179A\n");
        else
                aprint_normal_dev(self, "(unknown)\n");

        struct ethercom *ec = usbnet_ec(un);
        ec->ec_capabilities = ETHERCAP_VLAN_MTU;

        /* Adapter does not support TSOv6 (They call it LSOv2). */
        struct ifnet *ifp = usbnet_ifp(un);
        ifp->if_capabilities |= IFCAP_TSOv4 |
            IFCAP_CSUM_IPv4_Rx  | IFCAP_CSUM_IPv4_Tx  |
            IFCAP_CSUM_TCPv4_Rx | IFCAP_CSUM_TCPv4_Tx |
            IFCAP_CSUM_UDPv4_Rx | IFCAP_CSUM_UDPv4_Tx |
            IFCAP_CSUM_TCPv6_Rx | IFCAP_CSUM_TCPv6_Tx |
            IFCAP_CSUM_UDPv6_Rx | IFCAP_CSUM_UDPv6_Tx;

        usbnet_attach_ifp(un, IFF_SIMPLEX | IFF_BROADCAST | IFF_MULTICAST,
            0, &unm);
}

static int
axen_csum_flags_rx(struct ifnet *ifp, uint32_t pkt_hdr)
{
        int enabled_flags = ifp->if_csum_flags_rx;
        int csum_flags = 0;
        int l3_type, l4_type;

        if (enabled_flags == 0)
                return 0;

        l3_type = (pkt_hdr & AXEN_RXHDR_L3_TYPE_MASK) >>
            AXEN_RXHDR_L3_TYPE_OFFSET;

        if (l3_type == AXEN_RXHDR_L3_TYPE_IPV4)
                csum_flags |= M_CSUM_IPv4;

        l4_type = (pkt_hdr & AXEN_RXHDR_L4_TYPE_MASK) >>
            AXEN_RXHDR_L4_TYPE_OFFSET;

        switch (l4_type) {
        case AXEN_RXHDR_L4_TYPE_TCP:
                if (l3_type == AXEN_RXHDR_L3_TYPE_IPV4)
                        csum_flags |= M_CSUM_TCPv4;
                else
                        csum_flags |= M_CSUM_TCPv6;
                break;
        case AXEN_RXHDR_L4_TYPE_UDP:
                if (l3_type == AXEN_RXHDR_L3_TYPE_IPV4)
                        csum_flags |= M_CSUM_UDPv4;
                else
                        csum_flags |= M_CSUM_UDPv6;
                break;
        default:
                break;
        }

        csum_flags &= enabled_flags;
        if ((csum_flags & M_CSUM_IPv4) && (pkt_hdr & AXEN_RXHDR_L3CSUM_ERR))
                csum_flags |= M_CSUM_IPv4_BAD;
        if ((csum_flags & ~M_CSUM_IPv4) && (pkt_hdr & AXEN_RXHDR_L4CSUM_ERR))
                csum_flags |= M_CSUM_TCP_UDP_BAD;

        return csum_flags;
}

static void
axen_uno_rx_loop(struct usbnet *un, struct usbnet_chain *c, uint32_t total_len)
{
        struct ifnet *ifp = usbnet_ifp(un);
        uint8_t *buf = c->unc_buf;
        uint32_t rx_hdr, pkt_hdr;
        uint32_t *hdr_p;
        uint16_t hdr_offset, pkt_count;
        size_t pkt_len;
        size_t temp;

        if (total_len < sizeof(pkt_hdr)) {
                aprint_error_dev(un->un_dev, "rxeof: too short transfer\n");
                if_statinc(ifp, if_ierrors);
                return;
        }

        /*
         * buffer map
         * [packet #0]...[packet #n][pkt hdr#0]..[pkt hdr#n][recv_hdr]
         * each packet has 0xeeee as pseudo header..
         */
        hdr_p = (uint32_t *)(buf + total_len - sizeof(uint32_t));
        rx_hdr = le32toh(*hdr_p);
        hdr_offset = (uint16_t)(rx_hdr >> 16);
        pkt_count  = (uint16_t)(rx_hdr & 0xffff);

        /* sanity check */
        if (hdr_offset > total_len) {
                aprint_error_dev(un->un_dev,
                    "rxeof: invalid hdr offset (%u > %u)\n",
                    hdr_offset, total_len);
                if_statinc(ifp, if_ierrors);
                usbd_delay_ms(un->un_udev, 100);
                return;
        }

        /* point first packet header */
        hdr_p = (uint32_t *)(buf + hdr_offset);

        /*
         * ax88179 will pack multiple ip packet to a USB transaction.
         * process all of packets in the buffer
         */

#if 1 /* XXX: paranoiac check. need to remove later */
#define AXEN_MAX_PACKED_PACKET 200
        if (pkt_count > AXEN_MAX_PACKED_PACKET) {
                DPRINTF(("%s: Too many packets (%d) in a transaction, discard.\n",
                    device_xname(un->un_dev), pkt_count));
                return;
        }
#endif

        if (pkt_count)
                rnd_add_uint32(usbnet_rndsrc(un), pkt_count);

        while (pkt_count > 0) {
                if ((buf[0] != 0xee) || (buf[1] != 0xee)) {
                        aprint_error_dev(un->un_dev,
                            "invalid buffer(pkt#%d), continue\n", pkt_count);
                        if_statadd(ifp, if_ierrors, pkt_count);
                        return;
                }

                pkt_hdr = le32toh(*hdr_p);
                pkt_len = (pkt_hdr >> 16) & 0x1fff;
                DPRINTFN(10,
                    ("%s: rxeof: packet#%d, pkt_hdr 0x%08x, pkt_len %zu\n",
                   device_xname(un->un_dev), pkt_count, pkt_hdr, pkt_len));

                if (pkt_len < sizeof(struct ether_header) + ETHER_ALIGN)
                        goto nextpkt;

                if (pkt_hdr & (AXEN_RXHDR_CRC_ERR | AXEN_RXHDR_DROP_ERR)) {
                        if_statinc(ifp, if_ierrors);
                        /* move to next pkt header */
                        DPRINTF(("%s: %s err (pkt#%d)\n",
                            device_xname(un->un_dev),
                            (pkt_hdr & AXEN_RXHDR_CRC_ERR) ? "crc" : "drop",
                            pkt_count));
                        goto nextpkt;
                }

                if (un->un_flags & AX179A) {
                        /* each 88179A frame doesn't contain FCS. */
                        usbnet_enqueue(un, buf + ETHER_ALIGN, pkt_len - 2,
                               axen_csum_flags_rx(ifp, pkt_hdr), 0, 0);
                        /* 88179A next pkt_hdr looks bogus, skip it. */
                        hdr_p++;
                        pkt_count--;
                } else
                        usbnet_enqueue(un, buf + ETHER_ALIGN, pkt_len - 6,
                               axen_csum_flags_rx(ifp, pkt_hdr), 0, 0);

nextpkt:
                /*
                 * prepare next packet
                 * as each packet will be aligned 8byte boundary,
                 * need to fix up the start point of the buffer.
                 */
                temp = ((pkt_len + 7) & 0xfff8);
                buf = buf + temp;
                hdr_p++;
                if (pkt_count == 0)
                        break;
                pkt_count--;
        }
}

static unsigned
axen_uno_tx_prepare(struct usbnet *un, struct mbuf *m, struct usbnet_chain *c)
{
        struct axen_sframe_hdr hdr;
        u_int length, boundary;

        if ((unsigned)m->m_pkthdr.len > un->un_tx_bufsz - sizeof(hdr))
                return 0;
        length = m->m_pkthdr.len + sizeof(hdr);

        /* XXX Is this needed?  wMaxPacketSize? */
        switch (un->un_udev->ud_speed) {
        case USB_SPEED_SUPER:
                boundary = 4096;
                break;
        case USB_SPEED_HIGH:
                boundary = 512;
                break;
        default:
                boundary = 64;
                break;
        }

        hdr.plen = htole32(m->m_pkthdr.len);

        hdr.gso = (m->m_pkthdr.csum_flags & M_CSUM_TSOv4) ?
            m->m_pkthdr.segsz : 0;
        if ((length % boundary) == 0) {
                DPRINTF(("%s: boundary hit\n", device_xname(un->un_dev)));
                hdr.gso |= 0x80008000;  /* XXX enable padding */
        }
        hdr.gso = htole32(hdr.gso);

        memcpy(c->unc_buf, &hdr, sizeof(hdr));
        m_copydata(m, 0, m->m_pkthdr.len, c->unc_buf + sizeof(hdr));

        return length;
}

static int
axen_uno_init(struct ifnet *ifp)
{
        struct usbnet * const un = ifp->if_softc;
        uint16_t rxmode;
        uint16_t wval;
        uint8_t bval;

        /* Cancel pending I/O */
        axen_uno_stop(ifp, 1);

        /* Reset the ethernet interface. */
        axen_reset(un);

        /* XXX: ? */
        bval = 0x01;
        axen_cmd(un, AXEN_CMD_MAC_WRITE, 1, AXEN_UNK_28, &bval);

        /* Configure offloading engine. */
        axen_setoe_locked(un);

        /* Enable receiver, set RX mode */
        axen_cmd(un, AXEN_CMD_MAC_READ2, 2, AXEN_MAC_RXCTL, &wval);
        rxmode = le16toh(wval);
        rxmode |= AXEN_RXCTL_START;
        wval = htole16(rxmode);
        axen_cmd(un, AXEN_CMD_MAC_WRITE2, 2, AXEN_MAC_RXCTL, &wval);

        return 0;
}

static void
axen_uno_stop(struct ifnet *ifp, int disable)
{
        struct usbnet * const un = ifp->if_softc;
        uint16_t rxmode, wval;

        axen_reset(un);

        /* Disable receiver, set RX mode */
        axen_cmd(un, AXEN_CMD_MAC_READ2, 2, AXEN_MAC_RXCTL, &wval);
        rxmode = le16toh(wval);
        rxmode &= ~AXEN_RXCTL_START;
        wval = htole16(rxmode);
        axen_cmd(un, AXEN_CMD_MAC_WRITE2, 2, AXEN_MAC_RXCTL, &wval);
}

#ifdef _MODULE
#include "ioconf.c"
#endif

USBNET_MODULE(axen)