root/drivers/net/phy/bcm-cygnus.c
// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (C) 2015 Broadcom Corporation
 */

/* Broadcom Cygnus SoC internal transceivers support. */
#include "bcm-phy-lib.h"
#include <linux/brcmphy.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/phy.h>

struct bcm_omega_phy_priv {
        u64     *stats;
};

/* Broadcom Cygnus Phy specific registers */
#define MII_BCM_CYGNUS_AFE_VDAC_ICTRL_0  0x91E5 /* VDAL Control register */

static int bcm_cygnus_afe_config(struct phy_device *phydev)
{
        int rc;

        /* ensure smdspclk is enabled */
        rc = phy_write(phydev, MII_BCM54XX_AUX_CTL, 0x0c30);
        if (rc < 0)
                return rc;

        /* AFE_VDAC_ICTRL_0 bit 7:4 Iq=1100 for 1g 10bt, normal modes */
        rc = bcm_phy_write_misc(phydev, 0x39, 0x01, 0xA7C8);
        if (rc < 0)
                return rc;

        /* AFE_HPF_TRIM_OTHERS bit11=1, short cascode enable for all modes*/
        rc = bcm_phy_write_misc(phydev, 0x3A, 0x00, 0x0803);
        if (rc < 0)
                return rc;

        /* AFE_TX_CONFIG_1 bit 7:4 Iq=1100 for test modes */
        rc = bcm_phy_write_misc(phydev, 0x3A, 0x01, 0xA740);
        if (rc < 0)
                return rc;

        /* AFE TEMPSEN_OTHERS rcal_HT, rcal_LT 10000 */
        rc = bcm_phy_write_misc(phydev, 0x3A, 0x03, 0x8400);
        if (rc < 0)
                return rc;

        /* AFE_FUTURE_RSV bit 2:0 rccal <2:0>=100 */
        rc = bcm_phy_write_misc(phydev, 0x3B, 0x00, 0x0004);
        if (rc < 0)
                return rc;

        /* Adjust bias current trim to overcome digital offSet */
        rc = phy_write(phydev, MII_BRCM_CORE_BASE1E, 0x02);
        if (rc < 0)
                return rc;

        /* make rcal=100, since rdb default is 000 */
        rc = bcm_phy_write_exp_sel(phydev, MII_BRCM_CORE_EXPB1, 0x10);
        if (rc < 0)
                return rc;

        /* CORE_EXPB0, Reset R_CAL/RC_CAL Engine */
        rc = bcm_phy_write_exp_sel(phydev, MII_BRCM_CORE_EXPB0, 0x10);
        if (rc < 0)
                return rc;

        /* CORE_EXPB0, Disable Reset R_CAL/RC_CAL Engine */
        rc = bcm_phy_write_exp_sel(phydev, MII_BRCM_CORE_EXPB0, 0x00);

        return 0;
}

static int bcm_cygnus_config_init(struct phy_device *phydev)
{
        int reg, rc;

        reg = phy_read(phydev, MII_BCM54XX_ECR);
        if (reg < 0)
                return reg;

        /* Mask interrupts globally. */
        reg |= MII_BCM54XX_ECR_IM;
        rc = phy_write(phydev, MII_BCM54XX_ECR, reg);
        if (rc)
                return rc;

        /* Unmask events of interest */
        reg = ~(MII_BCM54XX_INT_DUPLEX |
                MII_BCM54XX_INT_SPEED |
                MII_BCM54XX_INT_LINK);
        rc = phy_write(phydev, MII_BCM54XX_IMR, reg);
        if (rc)
                return rc;

        /* Apply AFE settings for the PHY */
        rc = bcm_cygnus_afe_config(phydev);
        if (rc)
                return rc;

        /* Advertise EEE */
        rc = bcm_phy_set_eee(phydev, true);
        if (rc)
                return rc;

        /* Enable APD */
        return bcm_phy_enable_apd(phydev, false);
}

static int bcm_cygnus_resume(struct phy_device *phydev)
{
        int rc;

        genphy_resume(phydev);

        /* Re-initialize the PHY to apply AFE work-arounds and
         * configurations when coming out of suspend.
         */
        rc = bcm_cygnus_config_init(phydev);
        if (rc)
                return rc;

        /* restart auto negotiation with the new settings */
        return genphy_config_aneg(phydev);
}

static int bcm_omega_config_init(struct phy_device *phydev)
{
        u8 count, rev;
        int ret = 0;

        rev = phydev->phy_id & ~phydev->drv->phy_id_mask;

        pr_info_once("%s: %s PHY revision: 0x%02x\n",
                     phydev_name(phydev), phydev->drv->name, rev);

        /* Dummy read to a register to workaround an issue upon reset where the
         * internal inverter may not allow the first MDIO transaction to pass
         * the MDIO management controller and make us return 0xffff for such
         * reads.
         */
        phy_read(phydev, MII_BMSR);

        switch (rev) {
        case 0x00:
                ret = bcm_phy_28nm_a0b0_afe_config_init(phydev);
                break;
        default:
                break;
        }

        if (ret)
                return ret;

        ret = bcm_phy_downshift_get(phydev, &count);
        if (ret)
                return ret;

        /* Only enable EEE if Wirespeed/downshift is disabled */
        ret = bcm_phy_set_eee(phydev, count == DOWNSHIFT_DEV_DISABLE);
        if (ret)
                return ret;

        return bcm_phy_enable_apd(phydev, true);
}

static int bcm_omega_resume(struct phy_device *phydev)
{
        int ret;

        /* Re-apply workarounds coming out suspend/resume */
        ret = bcm_omega_config_init(phydev);
        if (ret)
                return ret;

        /* 28nm Gigabit PHYs come out of reset without any half-duplex
         * or "hub" compliant advertised mode, fix that. This does not
         * cause any problems with the PHY library since genphy_config_aneg()
         * gracefully handles auto-negotiated and forced modes.
         */
        return genphy_config_aneg(phydev);
}

static int bcm_omega_get_tunable(struct phy_device *phydev,
                                 struct ethtool_tunable *tuna, void *data)
{
        switch (tuna->id) {
        case ETHTOOL_PHY_DOWNSHIFT:
                return bcm_phy_downshift_get(phydev, (u8 *)data);
        default:
                return -EOPNOTSUPP;
        }
}

static int bcm_omega_set_tunable(struct phy_device *phydev,
                                 struct ethtool_tunable *tuna,
                                 const void *data)
{
        u8 count = *(u8 *)data;
        int ret;

        switch (tuna->id) {
        case ETHTOOL_PHY_DOWNSHIFT:
                ret = bcm_phy_downshift_set(phydev, count);
                break;
        default:
                return -EOPNOTSUPP;
        }

        if (ret)
                return ret;

        /* Disable EEE advertisement since this prevents the PHY
         * from successfully linking up, trigger auto-negotiation restart
         * to let the MAC decide what to do.
         */
        ret = bcm_phy_set_eee(phydev, count == DOWNSHIFT_DEV_DISABLE);
        if (ret)
                return ret;

        return genphy_restart_aneg(phydev);
}

static void bcm_omega_get_phy_stats(struct phy_device *phydev,
                                    struct ethtool_stats *stats, u64 *data)
{
        struct bcm_omega_phy_priv *priv = phydev->priv;

        bcm_phy_get_stats(phydev, priv->stats, stats, data);
}

static int bcm_omega_probe(struct phy_device *phydev)
{
        struct bcm_omega_phy_priv *priv;

        priv = devm_kzalloc(&phydev->mdio.dev, sizeof(*priv), GFP_KERNEL);
        if (!priv)
                return -ENOMEM;

        phydev->priv = priv;

        priv->stats = devm_kcalloc(&phydev->mdio.dev,
                                   bcm_phy_get_sset_count(phydev), sizeof(u64),
                                   GFP_KERNEL);
        if (!priv->stats)
                return -ENOMEM;

        return 0;
}

static struct phy_driver bcm_cygnus_phy_driver[] = {
{
        .phy_id        = PHY_ID_BCM_CYGNUS,
        .phy_id_mask   = 0xfffffff0,
        .name          = "Broadcom Cygnus PHY",
        /* PHY_GBIT_FEATURES */
        .config_init   = bcm_cygnus_config_init,
        .config_intr   = bcm_phy_config_intr,
        .handle_interrupt = bcm_phy_handle_interrupt,
        .suspend       = genphy_suspend,
        .resume        = bcm_cygnus_resume,
}, {
        .phy_id         = PHY_ID_BCM_OMEGA,
        .phy_id_mask    = 0xfffffff0,
        .name           = "Broadcom Omega Combo GPHY",
        /* PHY_GBIT_FEATURES */
        .flags          = PHY_IS_INTERNAL,
        .config_init    = bcm_omega_config_init,
        .suspend        = genphy_suspend,
        .resume         = bcm_omega_resume,
        .get_tunable    = bcm_omega_get_tunable,
        .set_tunable    = bcm_omega_set_tunable,
        .get_sset_count = bcm_phy_get_sset_count,
        .get_strings    = bcm_phy_get_strings,
        .get_stats      = bcm_omega_get_phy_stats,
        .probe          = bcm_omega_probe,
}
};

static const struct mdio_device_id __maybe_unused bcm_cygnus_phy_tbl[] = {
        { PHY_ID_BCM_CYGNUS, 0xfffffff0, },
        { PHY_ID_BCM_OMEGA, 0xfffffff0, },
        { }
};
MODULE_DEVICE_TABLE(mdio, bcm_cygnus_phy_tbl);

module_phy_driver(bcm_cygnus_phy_driver);

MODULE_DESCRIPTION("Broadcom Cygnus internal PHY driver");
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Broadcom Corporation");