/*
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * Copyright (C) 2011 - 2012 Cavium, Inc.
 */

#include <linux/module.h>
#include <linux/phy.h>
#include <linux/of.h>

#define PHY_ID_BCM8706  0x0143bdc1
#define PHY_ID_BCM8727  0x0143bff0

#define BCM87XX_PMD_RX_SIGNAL_DETECT    (MII_ADDR_C45 | 0x1000a)
#define BCM87XX_10GBASER_PCS_STATUS     (MII_ADDR_C45 | 0x30020)
#define BCM87XX_XGXS_LANE_STATUS        (MII_ADDR_C45 | 0x40018)

#define BCM87XX_LASI_CONTROL (MII_ADDR_C45 | 0x39002)
#define BCM87XX_LASI_STATUS (MII_ADDR_C45 | 0x39005)

#if IS_ENABLED(CONFIG_OF_MDIO)
/* Set and/or override some configuration registers based on the
 * broadcom,c45-reg-init property stored in the of_node for the phydev.
 *
 * broadcom,c45-reg-init = <devid reg mask value>,...;
 *
 * There may be one or more sets of <devid reg mask value>:
 *
 * devid: which sub-device to use.
 * reg: the register.
 * mask: if non-zero, ANDed with existing register value.
 * value: ORed with the masked value and written to the regiser.
 *
 */
static int bcm87xx_of_reg_init(struct phy_device *phydev)
{
        const __be32 *paddr;
        const __be32 *paddr_end;
        int len, ret;

        if (!phydev->dev.of_node)
                return 0;

        paddr = of_get_property(phydev->dev.of_node,
                                "broadcom,c45-reg-init", &len);
        if (!paddr)
                return 0;

        paddr_end = paddr + (len /= sizeof(*paddr));

        ret = 0;

        while (paddr + 3 < paddr_end) {
                u16 devid       = be32_to_cpup(paddr++);
                u16 reg         = be32_to_cpup(paddr++);
                u16 mask        = be32_to_cpup(paddr++);
                u16 val_bits    = be32_to_cpup(paddr++);
                int val;
                u32 regnum = MII_ADDR_C45 | (devid << 16) | reg;
                val = 0;
                if (mask) {
                        val = phy_read(phydev, regnum);
                        if (val < 0) {
                                ret = val;
                                goto err;
                        }
                        val &= mask;
                }
                val |= val_bits;

                ret = phy_write(phydev, regnum, val);
                if (ret < 0)
                        goto err;
        }
err:
        return ret;
}
#else
static int bcm87xx_of_reg_init(struct phy_device *phydev)
{
        return 0;
}
#endif /* CONFIG_OF_MDIO */

static int bcm87xx_config_init(struct phy_device *phydev)
{
        phydev->supported = SUPPORTED_10000baseR_FEC;
        phydev->advertising = ADVERTISED_10000baseR_FEC;
        phydev->state = PHY_NOLINK;
        phydev->autoneg = AUTONEG_DISABLE;

        bcm87xx_of_reg_init(phydev);

        return 0;
}

static int bcm87xx_config_aneg(struct phy_device *phydev)
{
        return -EINVAL;
}

static int bcm87xx_read_status(struct phy_device *phydev)
{
        int rx_signal_detect;
        int pcs_status;
        int xgxs_lane_status;

        rx_signal_detect = phy_read(phydev, BCM87XX_PMD_RX_SIGNAL_DETECT);
        if (rx_signal_detect < 0)
                return rx_signal_detect;

        if ((rx_signal_detect & 1) == 0)
                goto no_link;

        pcs_status = phy_read(phydev, BCM87XX_10GBASER_PCS_STATUS);
        if (pcs_status < 0)
                return pcs_status;

        if ((pcs_status & 1) == 0)
                goto no_link;

        xgxs_lane_status = phy_read(phydev, BCM87XX_XGXS_LANE_STATUS);
        if (xgxs_lane_status < 0)
                return xgxs_lane_status;

        if ((xgxs_lane_status & 0x1000) == 0)
                goto no_link;

        phydev->speed = 10000;
        phydev->link = 1;
        phydev->duplex = 1;
        return 0;

no_link:
        phydev->link = 0;
        return 0;
}

static int bcm87xx_config_intr(struct phy_device *phydev)
{
        int reg, err;

        reg = phy_read(phydev, BCM87XX_LASI_CONTROL);

        if (reg < 0)
                return reg;

        if (phydev->interrupts == PHY_INTERRUPT_ENABLED)
                reg |= 1;
        else
                reg &= ~1;

        err = phy_write(phydev, BCM87XX_LASI_CONTROL, reg);
        return err;
}

static int bcm87xx_did_interrupt(struct phy_device *phydev)
{
        int reg;

        reg = phy_read(phydev, BCM87XX_LASI_STATUS);

        if (reg < 0) {
                dev_err(&phydev->dev,
                        "Error: Read of BCM87XX_LASI_STATUS failed: %d\n", reg);
                return 0;
        }
        return (reg & 1) != 0;
}

static int bcm87xx_ack_interrupt(struct phy_device *phydev)
{
        /* Reading the LASI status clears it. */
        bcm87xx_did_interrupt(phydev);
        return 0;
}

static int bcm8706_match_phy_device(struct phy_device *phydev)
{
        return phydev->c45_ids.device_ids[4] == PHY_ID_BCM8706;
}

static int bcm8727_match_phy_device(struct phy_device *phydev)
{
        return phydev->c45_ids.device_ids[4] == PHY_ID_BCM8727;
}

static struct phy_driver bcm87xx_driver[] = {
{
        .phy_id         = PHY_ID_BCM8706,
        .phy_id_mask    = 0xffffffff,
        .name           = "Broadcom BCM8706",
        .flags          = PHY_HAS_INTERRUPT,
        .config_init    = bcm87xx_config_init,
        .config_aneg    = bcm87xx_config_aneg,
        .read_status    = bcm87xx_read_status,
        .ack_interrupt  = bcm87xx_ack_interrupt,
        .config_intr    = bcm87xx_config_intr,
        .did_interrupt  = bcm87xx_did_interrupt,
        .match_phy_device = bcm8706_match_phy_device,
        .driver         = { .owner = THIS_MODULE },
}, {
        .phy_id         = PHY_ID_BCM8727,
        .phy_id_mask    = 0xffffffff,
        .name           = "Broadcom BCM8727",
        .flags          = PHY_HAS_INTERRUPT,
        .config_init    = bcm87xx_config_init,
        .config_aneg    = bcm87xx_config_aneg,
        .read_status    = bcm87xx_read_status,
        .ack_interrupt  = bcm87xx_ack_interrupt,
        .config_intr    = bcm87xx_config_intr,
        .did_interrupt  = bcm87xx_did_interrupt,
        .match_phy_device = bcm8727_match_phy_device,
        .driver         = { .owner = THIS_MODULE },
} };

module_phy_driver(bcm87xx_driver);

MODULE_LICENSE("GPL");