/*
 * Generic PHY Management code
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of
 * the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
 * MA 02111-1307 USA
 *
 *
 * Copyright 2011 Freescale Semiconductor, Inc.
 * author Andy Fleming
 *
 * Based loosely off of Linux's PHY Lib
 */

#include <config.h>
#include <common.h>
#include <malloc.h>
#include <net.h>
#include <command.h>
#include <miiphy.h>
#include <phy.h>
#include <errno.h>
#include <linux/err.h>

/* Generic PHY support and helper functions */

/**
 * genphy_config_advert - sanitize and advertise auto-negotation parameters
 * @phydev: target phy_device struct
 *
 * Description: Writes MII_ADVERTISE with the appropriate values,
 *   after sanitizing the values to make sure we only advertise
 *   what is supported.  Returns < 0 on error, 0 if the PHY's advertisement
 *   hasn't changed, and > 0 if it has changed.
 */
static int genphy_config_advert(struct phy_device *phydev)
{
        u32 advertise;
        int oldadv, adv;
        int err, changed = 0;

        /* Only allow advertising what
         * this PHY supports */
        phydev->advertising &= phydev->supported;
        advertise = phydev->advertising;

        /* Setup standard advertisement */
        oldadv = adv = phy_read(phydev, MDIO_DEVAD_NONE, MII_ADVERTISE);

        if (adv < 0)
                return adv;

        adv &= ~(ADVERTISE_ALL | ADVERTISE_100BASE4 | ADVERTISE_PAUSE_CAP |
                 ADVERTISE_PAUSE_ASYM);
        if (advertise & ADVERTISED_10baseT_Half)
                adv |= ADVERTISE_10HALF;
        if (advertise & ADVERTISED_10baseT_Full)
                adv |= ADVERTISE_10FULL;
        if (advertise & ADVERTISED_100baseT_Half)
                adv |= ADVERTISE_100HALF;
        if (advertise & ADVERTISED_100baseT_Full)
                adv |= ADVERTISE_100FULL;
        if (advertise & ADVERTISED_Pause)
                adv |= ADVERTISE_PAUSE_CAP;
        if (advertise & ADVERTISED_Asym_Pause)
                adv |= ADVERTISE_PAUSE_ASYM;

        if (adv != oldadv) {
                err = phy_write(phydev, MDIO_DEVAD_NONE, MII_ADVERTISE, adv);

                if (err < 0)
                        return err;
                changed = 1;
        }

        /* Configure gigabit if it's supported */
        if (phydev->supported & (SUPPORTED_1000baseT_Half |
                                SUPPORTED_1000baseT_Full)) {
                oldadv = adv = phy_read(phydev, MDIO_DEVAD_NONE, MII_CTRL1000);

                if (adv < 0)
                        return adv;

                adv &= ~(ADVERTISE_1000FULL | ADVERTISE_1000HALF);
                if (advertise & SUPPORTED_1000baseT_Half)
                        adv |= ADVERTISE_1000HALF;
                if (advertise & SUPPORTED_1000baseT_Full)
                        adv |= ADVERTISE_1000FULL;

                if (adv != oldadv) {
                        err = phy_write(phydev, MDIO_DEVAD_NONE, MII_CTRL1000,
                                        adv);

                        if (err < 0)
                                return err;
                        changed = 1;
                }
        }

        return changed;
}


/**
 * genphy_setup_forced - configures/forces speed/duplex from @phydev
 * @phydev: target phy_device struct
 *
 * Description: Configures MII_BMCR to force speed/duplex
 *   to the values in phydev. Assumes that the values are valid.
 */
static int genphy_setup_forced(struct phy_device *phydev)
{
        int err;
        int ctl = 0;

        phydev->pause = phydev->asym_pause = 0;

        if (SPEED_1000 == phydev->speed)
                ctl |= BMCR_SPEED1000;
        else if (SPEED_100 == phydev->speed)
                ctl |= BMCR_SPEED100;

        if (DUPLEX_FULL == phydev->duplex)
                ctl |= BMCR_FULLDPLX;

        err = phy_write(phydev, MDIO_DEVAD_NONE, MII_BMCR, ctl);

        return err;
}


/**
 * genphy_restart_aneg - Enable and Restart Autonegotiation
 * @phydev: target phy_device struct
 */
int genphy_restart_aneg(struct phy_device *phydev)
{
        int ctl;

        ctl = phy_read(phydev, MDIO_DEVAD_NONE, MII_BMCR);

        if (ctl < 0)
                return ctl;

        ctl |= (BMCR_ANENABLE | BMCR_ANRESTART);

        /* Don't isolate the PHY if we're negotiating */
        ctl &= ~(BMCR_ISOLATE);

        ctl = phy_write(phydev, MDIO_DEVAD_NONE, MII_BMCR, ctl);

        return ctl;
}


/**
 * genphy_config_aneg - restart auto-negotiation or write BMCR
 * @phydev: target phy_device struct
 *
 * Description: If auto-negotiation is enabled, we configure the
 *   advertising, and then restart auto-negotiation.  If it is not
 *   enabled, then we write the BMCR.
 */
int genphy_config_aneg(struct phy_device *phydev)
{
        int result;

        if (AUTONEG_ENABLE != phydev->autoneg)
                return genphy_setup_forced(phydev);

        result = genphy_config_advert(phydev);

        if (result < 0) /* error */
                return result;

        if (result == 0) {
                /* Advertisment hasn't changed, but maybe aneg was never on to
                 * begin with?  Or maybe phy was isolated? */
                int ctl = phy_read(phydev, MDIO_DEVAD_NONE, MII_BMCR);

                if (ctl < 0)
                        return ctl;

                if (!(ctl & BMCR_ANENABLE) || (ctl & BMCR_ISOLATE))
                        result = 1; /* do restart aneg */
        }

        /* Only restart aneg if we are advertising something different
         * than we were before.  */
        if (result > 0)
                result = genphy_restart_aneg(phydev);

        return result;
}

/**
 * genphy_update_link - update link status in @phydev
 * @phydev: target phy_device struct
 *
 * Description: Update the value in phydev->link to reflect the
 *   current link value.  In order to do this, we need to read
 *   the status register twice, keeping the second value.
 */
int genphy_update_link(struct phy_device *phydev)
{
        unsigned int mii_reg;

        /*
         * Wait if the link is up, and autonegotiation is in progress
         * (ie - we're capable and it's not done)
         */
        mii_reg = phy_read(phydev, MDIO_DEVAD_NONE, MII_BMSR);

        /*
         * If we already saw the link up, and it hasn't gone down, then
         * we don't need to wait for autoneg again
         */
        if (phydev->link && mii_reg & BMSR_LSTATUS)
                return 0;

        if ((mii_reg & BMSR_ANEGCAPABLE) && !(mii_reg & BMSR_ANEGCOMPLETE)) {
                int i = 0;

                printf("%s Waiting for PHY auto negotiation to complete",
                        phydev->dev->name);
                while (!(mii_reg & BMSR_ANEGCOMPLETE)) {
                        /*
                         * Timeout reached ?
                         */
                        if (i > PHY_ANEG_TIMEOUT) {
                                printf(" TIMEOUT !\n");
                                phydev->link = 0;
                                return 0;
                        }

                        if (ctrlc()) {
                                puts("user interrupt!\n");
                                phydev->link = 0;
                                return -EINTR;
                        }

                        if ((i++ % 500) == 0)
                                printf(".");

                        udelay(1000);   /* 1 ms */
                        mii_reg = phy_read(phydev, MDIO_DEVAD_NONE, MII_BMSR);
                }
                printf(" done\n");
                phydev->link = 1;
        } else {
                /* Read the link a second time to clear the latched state */
                mii_reg = phy_read(phydev, MDIO_DEVAD_NONE, MII_BMSR);

                if (mii_reg & BMSR_LSTATUS)
                        phydev->link = 1;
                else
                        phydev->link = 0;
        }

        return 0;
}

/*
 * Generic function which updates the speed and duplex.  If
 * autonegotiation is enabled, it uses the AND of the link
 * partner's advertised capabilities and our advertised
 * capabilities.  If autonegotiation is disabled, we use the
 * appropriate bits in the control register.
 *
 * Stolen from Linux's mii.c and phy_device.c
 */
static int genphy_parse_link(struct phy_device *phydev)
{
        int mii_reg = phy_read(phydev, MDIO_DEVAD_NONE, MII_BMSR);

        /* We're using autonegotiation */
        if (mii_reg & BMSR_ANEGCAPABLE) {
                u32 lpa = 0;
                u32 gblpa = 0;

                /* Check for gigabit capability */
                if (mii_reg & BMSR_ERCAP) {
                        /* We want a list of states supported by
                         * both PHYs in the link
                         */
                        gblpa = phy_read(phydev, MDIO_DEVAD_NONE, MII_STAT1000);
                        gblpa &= phy_read(phydev,
                                        MDIO_DEVAD_NONE, MII_CTRL1000) << 2;
                }

                /* Set the baseline so we only have to set them
                 * if they're different
                 */
                phydev->speed = SPEED_10;
                phydev->duplex = DUPLEX_HALF;

                /* Check the gigabit fields */
                if (gblpa & (PHY_1000BTSR_1000FD | PHY_1000BTSR_1000HD)) {
                        phydev->speed = SPEED_1000;

                        if (gblpa & PHY_1000BTSR_1000FD)
                                phydev->duplex = DUPLEX_FULL;

                        /* We're done! */
                        return 0;
                }

                lpa = phy_read(phydev, MDIO_DEVAD_NONE, MII_ADVERTISE);
                lpa &= phy_read(phydev, MDIO_DEVAD_NONE, MII_LPA);

                if (lpa & (LPA_100FULL | LPA_100HALF)) {
                        phydev->speed = SPEED_100;

                        if (lpa & LPA_100FULL)
                                phydev->duplex = DUPLEX_FULL;

                } else if (lpa & LPA_10FULL)
                        phydev->duplex = DUPLEX_FULL;
        } else {
                u32 bmcr = phy_read(phydev, MDIO_DEVAD_NONE, MII_BMCR);

                phydev->speed = SPEED_10;
                phydev->duplex = DUPLEX_HALF;

                if (bmcr & BMCR_FULLDPLX)
                        phydev->duplex = DUPLEX_FULL;

                if (bmcr & BMCR_SPEED1000)
                        phydev->speed = SPEED_1000;
                else if (bmcr & BMCR_SPEED100)
                        phydev->speed = SPEED_100;
        }

        return 0;
}

int genphy_config(struct phy_device *phydev)
{
        int val;
        u32 features;

        /* For now, I'll claim that the generic driver supports
         * all possible port types */
        features = (SUPPORTED_TP | SUPPORTED_MII
                        | SUPPORTED_AUI | SUPPORTED_FIBRE |
                        SUPPORTED_BNC);

        /* Do we support autonegotiation? */
        val = phy_read(phydev, MDIO_DEVAD_NONE, MII_BMSR);

        if (val < 0)
                return val;

        if (val & BMSR_ANEGCAPABLE)
                features |= SUPPORTED_Autoneg;

        if (val & BMSR_100FULL)
                features |= SUPPORTED_100baseT_Full;
        if (val & BMSR_100HALF)
                features |= SUPPORTED_100baseT_Half;
        if (val & BMSR_10FULL)
                features |= SUPPORTED_10baseT_Full;
        if (val & BMSR_10HALF)
                features |= SUPPORTED_10baseT_Half;

        if (val & BMSR_ESTATEN) {
                val = phy_read(phydev, MDIO_DEVAD_NONE, MII_ESTATUS);

                if (val < 0)
                        return val;

                if (val & ESTATUS_1000_TFULL)
                        features |= SUPPORTED_1000baseT_Full;
                if (val & ESTATUS_1000_THALF)
                        features |= SUPPORTED_1000baseT_Half;
        }

        phydev->supported = features;
        phydev->advertising = features;

        genphy_config_aneg(phydev);

        return 0;
}

int genphy_startup(struct phy_device *phydev)
{
        genphy_update_link(phydev);
        genphy_parse_link(phydev);

        return 0;
}

int genphy_shutdown(struct phy_device *phydev)
{
        return 0;
}

static struct phy_driver genphy_driver = {
        .uid            = 0xffffffff,
        .mask           = 0xffffffff,
        .name           = "Generic PHY",
        .features       = 0,
        .config         = genphy_config,
        .startup        = genphy_startup,
        .shutdown       = genphy_shutdown,
};

static LIST_HEAD(phy_drivers);

int phy_init(void)
{
#ifdef CONFIG_PHY_ATHEROS
        phy_atheros_init();
#endif
#ifdef CONFIG_PHY_BROADCOM
        phy_broadcom_init();
#endif
#ifdef CONFIG_PHY_DAVICOM
        phy_davicom_init();
#endif
#ifdef CONFIG_PHY_LXT
        phy_lxt_init();
#endif
#ifdef CONFIG_PHY_MARVELL
        phy_marvell_init();
#endif
#ifdef CONFIG_PHY_MICREL
        phy_micrel_init();
#endif
#ifdef CONFIG_PHY_NATSEMI
        phy_natsemi_init();
#endif
#ifdef CONFIG_PHY_REALTEK
        phy_realtek_init();
#endif
#ifdef CONFIG_PHY_SMSC
        phy_smsc_init();
#endif
#ifdef CONFIG_PHY_TERANETICS
        phy_teranetics_init();
#endif
#ifdef CONFIG_PHY_VITESSE
        phy_vitesse_init();
#endif

        return 0;
}

int phy_register(struct phy_driver *drv)
{
        INIT_LIST_HEAD(&drv->list);
        list_add_tail(&drv->list, &phy_drivers);

        return 0;
}

static int phy_probe(struct phy_device *phydev)
{
        int err = 0;

        phydev->advertising = phydev->supported = phydev->drv->features;
        phydev->mmds = phydev->drv->mmds;

        if (phydev->drv->probe)
                err = phydev->drv->probe(phydev);

        return err;
}

static struct phy_driver *generic_for_interface(phy_interface_t interface)
{
#ifdef CONFIG_PHYLIB_10G
        if (is_10g_interface(interface))
                return &gen10g_driver;
#endif

        return &genphy_driver;
}

static struct phy_driver *get_phy_driver(struct phy_device *phydev,
                                phy_interface_t interface)
{
        struct list_head *entry;
        int phy_id = phydev->phy_id;
        struct phy_driver *drv = NULL;

        list_for_each(entry, &phy_drivers) {
                drv = list_entry(entry, struct phy_driver, list);
                if ((drv->uid & drv->mask) == (phy_id & drv->mask))
                        return drv;
        }

        /* If we made it here, there's no driver for this PHY */
        return generic_for_interface(interface);
}

static struct phy_device *phy_device_create(struct mii_dev *bus, int addr,
                                            int phy_id,
                                            phy_interface_t interface)
{
        struct phy_device *dev;

        /* We allocate the device, and initialize the
         * default values */
        dev = malloc(sizeof(*dev));
        if (!dev) {
                printf("Failed to allocate PHY device for %s:%d\n",
                        bus->name, addr);
                return NULL;
        }

        memset(dev, 0, sizeof(*dev));

        dev->duplex = -1;
        dev->link = 1;
        dev->interface = interface;

        dev->autoneg = AUTONEG_ENABLE;

        dev->addr = addr;
        dev->phy_id = phy_id;
        dev->bus = bus;

        dev->drv = get_phy_driver(dev, interface);

        phy_probe(dev);

        bus->phymap[addr] = dev;

        return dev;
}

/**
 * get_phy_id - reads the specified addr for its ID.
 * @bus: the target MII bus
 * @addr: PHY address on the MII bus
 * @phy_id: where to store the ID retrieved.
 *
 * Description: Reads the ID registers of the PHY at @addr on the
 *   @bus, stores it in @phy_id and returns zero on success.
 */
static int get_phy_id(struct mii_dev *bus, int addr, int devad, u32 *phy_id)
{
        int phy_reg;

        /* Grab the bits from PHYIR1, and put them
         * in the upper half */
        phy_reg = bus->read(bus, addr, devad, MII_PHYSID1);

        if (phy_reg < 0)
                return -EIO;

        *phy_id = (phy_reg & 0xffff) << 16;

        /* Grab the bits from PHYIR2, and put them in the lower half */
        phy_reg = bus->read(bus, addr, devad, MII_PHYSID2);

        if (phy_reg < 0)
                return -EIO;

        *phy_id |= (phy_reg & 0xffff);

        return 0;
}

static struct phy_device *create_phy_by_mask(struct mii_dev *bus,
                unsigned phy_mask, int devad, phy_interface_t interface)
{
        u32 phy_id = 0xffffffff;
        while (phy_mask) {
                int addr = ffs(phy_mask) - 1;
                int r = get_phy_id(bus, addr, devad, &phy_id);
                if (r < 0)
                        return ERR_PTR(r);
                /* If the PHY ID is mostly f's, we didn't find anything */
                if ((phy_id & 0x1fffffff) != 0x1fffffff)
                        return phy_device_create(bus, addr, phy_id, interface);
                phy_mask &= ~(1 << addr);
        }
        return NULL;
}

static struct phy_device *search_for_existing_phy(struct mii_dev *bus,
                unsigned phy_mask, phy_interface_t interface)
{
        /* If we have one, return the existing device, with new interface */
        while (phy_mask) {
                int addr = ffs(phy_mask) - 1;
                if (bus->phymap[addr]) {
                        bus->phymap[addr]->interface = interface;
                        return bus->phymap[addr];
                }
                phy_mask &= ~(1 << addr);
        }
        return NULL;
}

static struct phy_device *get_phy_device_by_mask(struct mii_dev *bus,
                unsigned phy_mask, phy_interface_t interface)
{
        int i;
        struct phy_device *phydev;

        phydev = search_for_existing_phy(bus, phy_mask, interface);
        if (phydev)
                return phydev;
        /* Try Standard (ie Clause 22) access */
        /* Otherwise we have to try Clause 45 */
        for (i = 0; i < 5; i++) {
                phydev = create_phy_by_mask(bus, phy_mask,
                                i ? i : MDIO_DEVAD_NONE, interface);
                if (IS_ERR(phydev))
                        return NULL;
                if (phydev)
                        return phydev;
        }
        printf("Phy not found\n");
        return phy_device_create(bus, ffs(phy_mask) - 1, 0xffffffff, interface);
}

/**
 * get_phy_device - reads the specified PHY device and returns its @phy_device struct
 * @bus: the target MII bus
 * @addr: PHY address on the MII bus
 *
 * Description: Reads the ID registers of the PHY at @addr on the
 *   @bus, then allocates and returns the phy_device to represent it.
 */
static struct phy_device *get_phy_device(struct mii_dev *bus, int addr,
                                         phy_interface_t interface)
{
        return get_phy_device_by_mask(bus, 1 << addr, interface);
}

int phy_reset(struct phy_device *phydev)
{
        int reg;
        int timeout = 500;
        int devad = MDIO_DEVAD_NONE;

#ifdef CONFIG_PHYLIB_10G
        /* If it's 10G, we need to issue reset through one of the MMDs */
        if (is_10g_interface(phydev->interface)) {
                if (!phydev->mmds)
                        gen10g_discover_mmds(phydev);

                devad = ffs(phydev->mmds) - 1;
        }
#endif

        reg = phy_read(phydev, devad, MII_BMCR);
        if (reg < 0) {
                debug("PHY status read failed\n");
                return -1;
        }

        reg |= BMCR_RESET;

        if (phy_write(phydev, devad, MII_BMCR, reg) < 0) {
                debug("PHY reset failed\n");
                return -1;
        }

#ifdef CONFIG_PHY_RESET_DELAY
        udelay(CONFIG_PHY_RESET_DELAY); /* Intel LXT971A needs this */
#endif
        /*
         * Poll the control register for the reset bit to go to 0 (it is
         * auto-clearing).  This should happen within 0.5 seconds per the
         * IEEE spec.
         */
        while ((reg & BMCR_RESET) && timeout--) {
                reg = phy_read(phydev, devad, MII_BMCR);

                if (reg < 0) {
                        debug("PHY status read failed\n");
                        return -1;
                }
                udelay(1000);
        }

        if (reg & BMCR_RESET) {
                puts("PHY reset timed out\n");
                return -1;
        }

        return 0;
}

int miiphy_reset(const char *devname, unsigned char addr)
{
        struct mii_dev *bus = miiphy_get_dev_by_name(devname);
        struct phy_device *phydev;

        /*
         * miiphy_reset was only used on standard PHYs, so we'll fake it here.
         * If later code tries to connect with the right interface, this will
         * be corrected by get_phy_device in phy_connect()
         */
        phydev = get_phy_device(bus, addr, PHY_INTERFACE_MODE_MII);

        return phy_reset(phydev);
}

struct phy_device *phy_find_by_mask(struct mii_dev *bus, unsigned phy_mask,
                phy_interface_t interface)
{
        /* Reset the bus */
        if (bus->reset)
                bus->reset(bus);

        /* Wait 15ms to make sure the PHY has come out of hard reset */
        udelay(15000);
        return get_phy_device_by_mask(bus, phy_mask, interface);
}

void phy_connect_dev(struct phy_device *phydev, struct eth_device *dev)
{
        /* Soft Reset the PHY */
        phy_reset(phydev);
        if (phydev->dev) {
                printf("%s:%d is connected to %s.  Reconnecting to %s\n",
                                phydev->bus->name, phydev->addr,
                                phydev->dev->name, dev->name);
        }
        phydev->dev = dev;
        debug("%s connected to %s\n", dev->name, phydev->drv->name);
}

struct phy_device *phy_connect(struct mii_dev *bus, int addr,
                struct eth_device *dev, phy_interface_t interface)
{
        struct phy_device *phydev;

        phydev = phy_find_by_mask(bus, 1 << addr, interface);
        if (phydev)
                phy_connect_dev(phydev, dev);
        else
                printf("Could not get PHY for %s: addr %d\n", bus->name, addr);
        return phydev;
}

/*
 * Start the PHY.  Returns 0 on success, or a negative error code.
 */
int phy_startup(struct phy_device *phydev)
{
        if (phydev->drv->startup)
                return phydev->drv->startup(phydev);

        return 0;
}

static int __board_phy_config(struct phy_device *phydev)
{
        if (phydev->drv->config)
                return phydev->drv->config(phydev);
        return 0;
}

int board_phy_config(struct phy_device *phydev)
        __attribute__((weak, alias("__board_phy_config")));

int phy_config(struct phy_device *phydev)
{
        /* Invoke an optional board-specific helper */
        board_phy_config(phydev);

        return 0;
}

int phy_shutdown(struct phy_device *phydev)
{
        if (phydev->drv->shutdown)
                phydev->drv->shutdown(phydev);

        return 0;
}