/*
 * (C) Copyright 2001
 * Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com.
 *
 * See file CREDITS for list of people who contributed to this
 * project.
 *
 * 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
 */

/*
 * This provides a bit-banged interface to the ethernet MII management
 * channel.
 */

#include <common.h>
#include <miiphy.h>

#include <asm/types.h>
#include <linux/list.h>
#include <malloc.h>
#include <net.h>

/* local debug macro */
#undef MII_DEBUG

#undef debug
#ifdef MII_DEBUG
#define debug(fmt,args...)      printf (fmt ,##args)
#else
#define debug(fmt,args...)
#endif /* MII_DEBUG */

struct mii_dev {
        struct list_head link;
        const char *name;
        int (*read) (const char *devname, unsigned char addr,
                     unsigned char reg, unsigned short *value);
        int (*write) (const char *devname, unsigned char addr,
                      unsigned char reg, unsigned short value);
};

static struct list_head mii_devs;
static struct mii_dev *current_mii;

/*
 * Lookup the mii_dev struct by the registered device name.
 */
static struct mii_dev *miiphy_get_dev_by_name(const char *devname, int quiet)
{
        struct list_head *entry;
        struct mii_dev *dev;

        if (!devname) {
                printf("NULL device name!\n");
                return NULL;
        }

        list_for_each(entry, &mii_devs) {
                dev = list_entry(entry, struct mii_dev, link);
                if (strcmp(dev->name, devname) == 0)
                        return dev;
        }

        if (!quiet)
                printf("No such device: %s\n", devname);
        return NULL;
}

/*****************************************************************************
 *
 * Initialize global data. Need to be called before any other miiphy routine.
 */
void miiphy_init(void)
{
        INIT_LIST_HEAD (&mii_devs);
        current_mii = NULL;
}

/*****************************************************************************
 *
 * Register read and write MII access routines for the device <name>.
 */
void miiphy_register(const char *name,
                      int (*read) (const char *devname, unsigned char addr,
                                   unsigned char reg, unsigned short *value),
                      int (*write) (const char *devname, unsigned char addr,
                                    unsigned char reg, unsigned short value))
{
        struct mii_dev *new_dev;
        unsigned int name_len;
        char *new_name;

        /* check if we have unique name */
        new_dev = miiphy_get_dev_by_name(name, 1);
        if (new_dev) {
                printf("miiphy_register: non unique device name '%s'\n", name);
                return;
        }

        /* allocate memory */
        name_len = strlen (name);
        new_dev =
            (struct mii_dev *)malloc (sizeof (struct mii_dev) + name_len + 1);

        if (new_dev == NULL) {
                printf ("miiphy_register: cannot allocate memory for '%s'\n",
                        name);
                return;
        }
        memset (new_dev, 0, sizeof (struct mii_dev) + name_len);

        /* initalize mii_dev struct fields */
        INIT_LIST_HEAD (&new_dev->link);
        new_dev->read = read;
        new_dev->write = write;
        new_dev->name = new_name = (char *)(new_dev + 1);
        strncpy (new_name, name, name_len);
        new_name[name_len] = '\0';

        debug ("miiphy_register: added '%s', read=0x%08lx, write=0x%08lx\n",
               new_dev->name, new_dev->read, new_dev->write);

        /* add it to the list */
        list_add_tail (&new_dev->link, &mii_devs);

        if (!current_mii)
                current_mii = new_dev;
}

int miiphy_set_current_dev(const char *devname)
{
        struct mii_dev *dev;

        dev = miiphy_get_dev_by_name(devname, 0);
        if (dev) {
                current_mii = dev;
                return 0;
        }

        return 1;
}

const char *miiphy_get_current_dev(void)
{
        if (current_mii)
                return current_mii->name;

        return NULL;
}

static struct mii_dev *miiphy_get_active_dev(const char *devname)
{
        /* If the current mii is the one we want, return it */
        if (current_mii)
                if (strcmp(current_mii->name, devname) == 0)
                        return current_mii;

        /* Otherwise, set the active one to the one we want */
        if (miiphy_set_current_dev(devname))
                return NULL;
        else
                return current_mii;
}

/*****************************************************************************
 *
 * Read to variable <value> from the PHY attached to device <devname>,
 * use PHY address <addr> and register <reg>.
 *
 * Returns:
 *   0 on success
 */
int miiphy_read(const char *devname, unsigned char addr, unsigned char reg,
                 unsigned short *value)
{
        struct mii_dev *dev;

        dev = miiphy_get_active_dev(devname);
        if (dev)
                return dev->read(devname, addr, reg, value);

        return 1;
}

/*****************************************************************************
 *
 * Write <value> to the PHY attached to device <devname>,
 * use PHY address <addr> and register <reg>.
 *
 * Returns:
 *   0 on success
 */
int miiphy_write(const char *devname, unsigned char addr, unsigned char reg,
                  unsigned short value)
{
        struct mii_dev *dev;

        dev = miiphy_get_active_dev(devname);
        if (dev)
                return dev->write(devname, addr, reg, value);

        return 1;
}

/*****************************************************************************
 *
 * Print out list of registered MII capable devices.
 */
void miiphy_listdev (void)
{
        struct list_head *entry;
        struct mii_dev *dev;

        puts ("MII devices: ");
        list_for_each (entry, &mii_devs) {
                dev = list_entry (entry, struct mii_dev, link);
                printf ("'%s' ", dev->name);
        }
        puts ("\n");

        if (current_mii)
                printf ("Current device: '%s'\n", current_mii->name);
}

/*****************************************************************************
 *
 * Read the OUI, manufacture's model number, and revision number.
 *
 * OUI:     22 bits (unsigned int)
 * Model:    6 bits (unsigned char)
 * Revision: 4 bits (unsigned char)
 *
 * Returns:
 *   0 on success
 */
int miiphy_info(const char *devname, unsigned char addr, unsigned int *oui,
                 unsigned char *model, unsigned char *rev)
{
        unsigned int reg = 0;
        unsigned short tmp;

        if (miiphy_read (devname, addr, PHY_PHYIDR2, &tmp) != 0) {
                debug ("PHY ID register 2 read failed\n");
                return (-1);
        }
        reg = tmp;

        debug ("PHY_PHYIDR2 @ 0x%x = 0x%04x\n", addr, reg);

        if (reg == 0xFFFF) {
                /* No physical device present at this address */
                return (-1);
        }

        if (miiphy_read (devname, addr, PHY_PHYIDR1, &tmp) != 0) {
                debug ("PHY ID register 1 read failed\n");
                return (-1);
        }
        reg |= tmp << 16;
        debug ("PHY_PHYIDR[1,2] @ 0x%x = 0x%08x\n", addr, reg);

        *oui = (reg >> 10);
        *model = (unsigned char)((reg >> 4) & 0x0000003F);
        *rev = (unsigned char)(reg & 0x0000000F);
        return (0);
}

/*****************************************************************************
 *
 * Reset the PHY.
 * Returns:
 *   0 on success
 */
int miiphy_reset(const char *devname, unsigned char addr)
{
        unsigned short reg;
        int timeout = 500;

        if (miiphy_read (devname, addr, PHY_BMCR, &reg) != 0) {
                debug ("PHY status read failed\n");
                return (-1);
        }
        if (miiphy_write (devname, addr, PHY_BMCR, reg | PHY_BMCR_RESET) != 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.
         */
        reg = 0x8000;
        while (((reg & 0x8000) != 0) && timeout--) {
                if (miiphy_read(devname, addr, PHY_BMCR, &reg) != 0) {
                        debug("PHY status read failed\n");
                        return -1;
                }
                udelay(1000);
        }
        if ((reg & 0x8000) == 0) {
                return (0);
        } else {
                puts ("PHY reset timed out\n");
                return (-1);
        }
        return (0);
}

/*****************************************************************************
 *
 * Determine the ethernet speed (10/100/1000).  Return 10 on error.
 */
int miiphy_speed(const char *devname, unsigned char addr)
{
        u16 bmcr, anlpar;

#if defined(CONFIG_PHY_GIGE)
        u16 btsr;

        /*
         * Check for 1000BASE-X.  If it is supported, then assume that the speed
         * is 1000.
         */
        if (miiphy_is_1000base_x (devname, addr)) {
                return _1000BASET;
        }
        /*
         * No 1000BASE-X, so assume 1000BASE-T/100BASE-TX/10BASE-T register set.
         */
        /* Check for 1000BASE-T. */
        if (miiphy_read (devname, addr, PHY_1000BTSR, &btsr)) {
                printf ("PHY 1000BT status");
                goto miiphy_read_failed;
        }
        if (btsr != 0xFFFF &&
            (btsr & (PHY_1000BTSR_1000FD | PHY_1000BTSR_1000HD))) {
                return _1000BASET;
        }
#endif /* CONFIG_PHY_GIGE */

        /* Check Basic Management Control Register first. */
        if (miiphy_read (devname, addr, PHY_BMCR, &bmcr)) {
                printf ("PHY speed");
                goto miiphy_read_failed;
        }
        /* Check if auto-negotiation is on. */
        if (bmcr & PHY_BMCR_AUTON) {
                /* Get auto-negotiation results. */
                if (miiphy_read (devname, addr, PHY_ANLPAR, &anlpar)) {
                        printf ("PHY AN speed");
                        goto miiphy_read_failed;
                }
                return (anlpar & PHY_ANLPAR_100) ? _100BASET : _10BASET;
        }
        /* Get speed from basic control settings. */
        return (bmcr & PHY_BMCR_100MB) ? _100BASET : _10BASET;

miiphy_read_failed:
        printf (" read failed, assuming 10BASE-T\n");
        return _10BASET;
}

/*****************************************************************************
 *
 * Determine full/half duplex.  Return half on error.
 */
int miiphy_duplex(const char *devname, unsigned char addr)
{
        u16 bmcr, anlpar;

#if defined(CONFIG_PHY_GIGE)
        u16 btsr;

        /* Check for 1000BASE-X. */
        if (miiphy_is_1000base_x (devname, addr)) {
                /* 1000BASE-X */
                if (miiphy_read (devname, addr, PHY_ANLPAR, &anlpar)) {
                        printf ("1000BASE-X PHY AN duplex");
                        goto miiphy_read_failed;
                }
        }
        /*
         * No 1000BASE-X, so assume 1000BASE-T/100BASE-TX/10BASE-T register set.
         */
        /* Check for 1000BASE-T. */
        if (miiphy_read (devname, addr, PHY_1000BTSR, &btsr)) {
                printf ("PHY 1000BT status");
                goto miiphy_read_failed;
        }
        if (btsr != 0xFFFF) {
                if (btsr & PHY_1000BTSR_1000FD) {
                        return FULL;
                } else if (btsr & PHY_1000BTSR_1000HD) {
                        return HALF;
                }
        }
#endif /* CONFIG_PHY_GIGE */

        /* Check Basic Management Control Register first. */
        if (miiphy_read (devname, addr, PHY_BMCR, &bmcr)) {
                puts ("PHY duplex");
                goto miiphy_read_failed;
        }
        /* Check if auto-negotiation is on. */
        if (bmcr & PHY_BMCR_AUTON) {
                /* Get auto-negotiation results. */
                if (miiphy_read (devname, addr, PHY_ANLPAR, &anlpar)) {
                        puts ("PHY AN duplex");
                        goto miiphy_read_failed;
                }
                return (anlpar & (PHY_ANLPAR_10FD | PHY_ANLPAR_TXFD)) ?
                    FULL : HALF;
        }
        /* Get speed from basic control settings. */
        return (bmcr & PHY_BMCR_DPLX) ? FULL : HALF;

miiphy_read_failed:
        printf (" read failed, assuming half duplex\n");
        return HALF;
}

/*****************************************************************************
 *
 * Return 1 if PHY supports 1000BASE-X, 0 if PHY supports 10BASE-T/100BASE-TX/
 * 1000BASE-T, or on error.
 */
int miiphy_is_1000base_x(const char *devname, unsigned char addr)
{
#if defined(CONFIG_PHY_GIGE)
        u16 exsr;

        if (miiphy_read (devname, addr, PHY_EXSR, &exsr)) {
                printf ("PHY extended status read failed, assuming no "
                        "1000BASE-X\n");
                return 0;
        }
        return 0 != (exsr & (PHY_EXSR_1000XF | PHY_EXSR_1000XH));
#else
        return 0;
#endif
}

#ifdef CONFIG_SYS_FAULT_ECHO_LINK_DOWN
/*****************************************************************************
 *
 * Determine link status
 */
int miiphy_link(const char *devname, unsigned char addr)
{
        unsigned short reg;

        /* dummy read; needed to latch some phys */
        (void)miiphy_read (devname, addr, PHY_BMSR, &reg);
        if (miiphy_read (devname, addr, PHY_BMSR, &reg)) {
                puts ("PHY_BMSR read failed, assuming no link\n");
                return (0);
        }

        /* Determine if a link is active */
        if ((reg & PHY_BMSR_LS) != 0) {
                return (1);
        } else {
                return (0);
        }
}
#endif