// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Applied Micro X-Gene SoC Ethernet v2 Driver
 *
 * Copyright (c) 2017, Applied Micro Circuits Corporation
 * Author(s): Iyappan Subramanian <isubramanian@apm.com>
 *            Keyur Chudgar <kchudgar@apm.com>
 */

#include "main.h"

static int xge_mdio_write(struct mii_bus *bus, int phy_id, int reg, u16 data)
{
        struct xge_pdata *pdata = bus->priv;
        u32 done, val = 0;
        u8 wait = 10;

        SET_REG_BITS(&val, PHY_ADDR, phy_id);
        SET_REG_BITS(&val, REG_ADDR, reg);
        xge_wr_csr(pdata, MII_MGMT_ADDRESS, val);

        xge_wr_csr(pdata, MII_MGMT_CONTROL, data);
        do {
                usleep_range(5, 10);
                done = xge_rd_csr(pdata, MII_MGMT_INDICATORS);
        } while ((done & MII_MGMT_BUSY) && wait--);

        if (done & MII_MGMT_BUSY) {
                dev_err(&bus->dev, "MII_MGMT write failed\n");
                return -ETIMEDOUT;
        }

        return 0;
}

static int xge_mdio_read(struct mii_bus *bus, int phy_id, int reg)
{
        struct xge_pdata *pdata = bus->priv;
        u32 data, done, val = 0;
        u8 wait = 10;

        SET_REG_BITS(&val, PHY_ADDR, phy_id);
        SET_REG_BITS(&val, REG_ADDR, reg);
        xge_wr_csr(pdata, MII_MGMT_ADDRESS, val);

        xge_wr_csr(pdata, MII_MGMT_COMMAND, MII_READ_CYCLE);
        do {
                usleep_range(5, 10);
                done = xge_rd_csr(pdata, MII_MGMT_INDICATORS);
        } while ((done & MII_MGMT_BUSY) && wait--);

        if (done & MII_MGMT_BUSY) {
                dev_err(&bus->dev, "MII_MGMT read failed\n");
                return -ETIMEDOUT;
        }

        data = xge_rd_csr(pdata, MII_MGMT_STATUS);
        xge_wr_csr(pdata, MII_MGMT_COMMAND, 0);

        return data;
}

static void xge_adjust_link(struct net_device *ndev)
{
        struct xge_pdata *pdata = netdev_priv(ndev);
        struct phy_device *phydev = ndev->phydev;

        if (phydev->link) {
                if (pdata->phy_speed != phydev->speed) {
                        pdata->phy_speed = phydev->speed;
                        xge_mac_set_speed(pdata);
                        xge_mac_enable(pdata);
                        phy_print_status(phydev);
                }
        } else {
                if (pdata->phy_speed != SPEED_UNKNOWN) {
                        pdata->phy_speed = SPEED_UNKNOWN;
                        xge_mac_disable(pdata);
                        phy_print_status(phydev);
                }
        }
}

void xge_mdio_remove(struct net_device *ndev)
{
        struct xge_pdata *pdata = netdev_priv(ndev);
        struct mii_bus *mdio_bus = pdata->mdio_bus;

        if (ndev->phydev)
                phy_disconnect(ndev->phydev);

        if (mdio_bus->state == MDIOBUS_REGISTERED)
                mdiobus_unregister(mdio_bus);

        mdiobus_free(mdio_bus);
}

int xge_mdio_config(struct net_device *ndev)
{
        struct xge_pdata *pdata = netdev_priv(ndev);
        struct device *dev = &pdata->pdev->dev;
        struct mii_bus *mdio_bus;
        struct phy_device *phydev;
        int ret;

        mdio_bus = mdiobus_alloc();
        if (!mdio_bus)
                return -ENOMEM;

        mdio_bus->name = "APM X-Gene Ethernet (v2) MDIO Bus";
        mdio_bus->read = xge_mdio_read;
        mdio_bus->write = xge_mdio_write;
        mdio_bus->priv = pdata;
        mdio_bus->parent = dev;
        snprintf(mdio_bus->id, MII_BUS_ID_SIZE, "%s-mii", dev_name(dev));
        pdata->mdio_bus = mdio_bus;

        mdio_bus->phy_mask = 0x1;
        ret = mdiobus_register(mdio_bus);
        if (ret)
                goto err;

        phydev = phy_find_first(mdio_bus);
        if (!phydev) {
                dev_err(dev, "no PHY found\n");
                ret = -ENODEV;
                goto err;
        }
        phydev = phy_connect(ndev, phydev_name(phydev),
                             &xge_adjust_link,
                             pdata->resources.phy_mode);

        if (IS_ERR(phydev)) {
                netdev_err(ndev, "Could not attach to PHY\n");
                ret = PTR_ERR(phydev);
                goto err;
        }

        phy_remove_link_mode(phydev, ETHTOOL_LINK_MODE_10baseT_Half_BIT);
        phy_remove_link_mode(phydev, ETHTOOL_LINK_MODE_10baseT_Full_BIT);
        phy_remove_link_mode(phydev, ETHTOOL_LINK_MODE_100baseT_Half_BIT);
        phy_remove_link_mode(phydev, ETHTOOL_LINK_MODE_100baseT_Full_BIT);
        phy_remove_link_mode(phydev, ETHTOOL_LINK_MODE_1000baseT_Half_BIT);

        pdata->phy_speed = SPEED_UNKNOWN;

        return 0;
err:
        xge_mdio_remove(ndev);

        return ret;
}