/*
 * Marvell 10G 88x3310 PHY driver
 *
 * Based upon the ID registers, this PHY appears to be a mixture of IPs
 * from two different companies.
 *
 * There appears to be several different data paths through the PHY which
 * are automatically managed by the PHY.  The following has been determined
 * via observation and experimentation:
 *
 *       SGMII PHYXS -- BASE-T PCS -- 10G PMA -- AN -- Copper (for <= 1G)
 *  10GBASE-KR PHYXS -- BASE-T PCS -- 10G PMA -- AN -- Copper (for 10G)
 *  10GBASE-KR PHYXS -- BASE-R PCS -- Fiber
 *
 * If both the fiber and copper ports are connected, the first to gain
 * link takes priority and the other port is completely locked out.
 */
#include <linux/of.h>
#include <linux/phy.h>
#include <linux/sfp.h>

enum {
	MV_PCS_BASE_T		= 0x0000,
	MV_PCS_BASE_R		= 0x1000,
	MV_PCS_1000BASEX	= 0x2000,

	/* These registers appear at 0x800X and 0xa00X - the 0xa00X control
	 * registers appear to set themselves to the 0x800X when AN is
	 * restarted, but status registers appear readable from either.
	 */
	MV_AN_CTRL1000		= 0x8000, /* 1000base-T control register */
	MV_AN_STAT1000		= 0x8001, /* 1000base-T status register */

	/* This register appears to reflect the copper status */
	MV_AN_RESULT		= 0xa016,
	MV_AN_RESULT_SPD_10	= BIT(12),
	MV_AN_RESULT_SPD_100	= BIT(13),
	MV_AN_RESULT_SPD_1000	= BIT(14),
	MV_AN_RESULT_SPD_10000	= BIT(15),
};

struct mv3310_priv {
	struct device_node *sfp_node;
	struct sfp_bus *sfp_bus;
};

static int mv3310_modify(struct phy_device *phydev, int devad, u16 reg,
			 u16 mask, u16 bits)
{
	int old, val, ret;

	old = phy_read_mmd(phydev, devad, reg);
	if (old < 0)
		return old;

	val = (old & ~mask) | (bits & mask);
	if (val == old)
		return 0;

	ret = phy_write_mmd(phydev, devad, reg, val);

	return ret < 0 ? ret : 1;
}

static int mv3310_sfp_insert(void *upstream, const struct sfp_eeprom_id *id)
{
	struct phy_device *phydev = upstream;
	struct mv3310_priv *priv = dev_get_drvdata(&phydev->mdio.dev);

	if (sfp_parse_interface(priv->sfp_bus, id) != PHY_INTERFACE_MODE_10GKR) {
		dev_err(&phydev->mdio.dev, "incompatible SFP module inserted\n");
		return -EINVAL;
	}
	return 0;
}

static const struct sfp_upstream_ops mv3310_sfp_ops = {
	.module_insert = mv3310_sfp_insert,
};

static int mv3310_probe(struct phy_device *phydev)
{
	struct mv3310_priv *priv;
	u32 mmd_mask = MDIO_DEVS_PMAPMD | MDIO_DEVS_AN;

	if (!phydev->is_c45 ||
	    (phydev->c45_ids.devices_in_package & mmd_mask) != mmd_mask)
		return -ENODEV;

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

	dev_set_drvdata(&phydev->mdio.dev, priv);

	if (phydev->mdio.dev.of_node)
		priv->sfp_node = of_parse_phandle(phydev->mdio.dev.of_node,
						  "sfp", 0);

	return 0;
}

static void mv3310_remove(struct phy_device *phydev)
{
	struct mv3310_priv *priv = dev_get_drvdata(&phydev->mdio.dev);

	if (priv->sfp_bus)
		sfp_unregister_upstream(priv->sfp_bus);
}

/*
 * Resetting the MV88X3310 causes it to become non-responsive.  Avoid
 * setting the reset bit(s).
 */
static int mv3310_soft_reset(struct phy_device *phydev)
{
	return 0;
}

static int mv3310_config_init(struct phy_device *phydev)
{
	struct mv3310_priv *priv = dev_get_drvdata(&phydev->mdio.dev);
	__ETHTOOL_DECLARE_LINK_MODE_MASK(supported) = { 0, };
	u32 mask;
	int val;

	/* Check that the PHY interface type is compatible */
	if (phydev->interface != PHY_INTERFACE_MODE_SGMII &&
	    phydev->interface != PHY_INTERFACE_MODE_XGMII &&
	    phydev->interface != PHY_INTERFACE_MODE_XAUI &&
	    phydev->interface != PHY_INTERFACE_MODE_RXAUI &&
	    phydev->interface != PHY_INTERFACE_MODE_10GKR)
		return -ENODEV;

	__set_bit(ETHTOOL_LINK_MODE_Pause_BIT, supported);
	__set_bit(ETHTOOL_LINK_MODE_Asym_Pause_BIT, supported);

	if (phydev->c45_ids.devices_in_package & MDIO_DEVS_AN) {
		val = phy_read_mmd(phydev, MDIO_MMD_AN, MDIO_STAT1);
		if (val < 0)
			return val;

		if (val & MDIO_AN_STAT1_ABLE)
			__set_bit(ETHTOOL_LINK_MODE_Autoneg_BIT, supported);
	}

	val = phy_read_mmd(phydev, MDIO_MMD_PMAPMD, MDIO_STAT2);
	if (val < 0)
		return val;

	/* Ethtool does not support the WAN mode bits */
	if (val & (MDIO_PMA_STAT2_10GBSR | MDIO_PMA_STAT2_10GBLR |
		   MDIO_PMA_STAT2_10GBER | MDIO_PMA_STAT2_10GBLX4 |
		   MDIO_PMA_STAT2_10GBSW | MDIO_PMA_STAT2_10GBLW |
		   MDIO_PMA_STAT2_10GBEW))
		__set_bit(ETHTOOL_LINK_MODE_FIBRE_BIT, supported);
	if (val & MDIO_PMA_STAT2_10GBSR)
		__set_bit(ETHTOOL_LINK_MODE_10000baseSR_Full_BIT, supported);
	if (val & MDIO_PMA_STAT2_10GBLR)
		__set_bit(ETHTOOL_LINK_MODE_10000baseLR_Full_BIT, supported);
	if (val & MDIO_PMA_STAT2_10GBER)
		__set_bit(ETHTOOL_LINK_MODE_10000baseER_Full_BIT, supported);

	if (val & MDIO_PMA_STAT2_EXTABLE) {
		val = phy_read_mmd(phydev, MDIO_MMD_PMAPMD, MDIO_PMA_EXTABLE);
		if (val < 0)
			return val;

		if (val & (MDIO_PMA_EXTABLE_10GBT | MDIO_PMA_EXTABLE_1000BT |
			   MDIO_PMA_EXTABLE_100BTX | MDIO_PMA_EXTABLE_10BT))
			__set_bit(ETHTOOL_LINK_MODE_TP_BIT, supported);
		if (val & MDIO_PMA_EXTABLE_10GBLRM)
			__set_bit(ETHTOOL_LINK_MODE_FIBRE_BIT, supported);
		if (val & (MDIO_PMA_EXTABLE_10GBKX4 | MDIO_PMA_EXTABLE_10GBKR |
			   MDIO_PMA_EXTABLE_1000BKX))
			__set_bit(ETHTOOL_LINK_MODE_Backplane_BIT, supported);
		if (val & MDIO_PMA_EXTABLE_10GBLRM)
			__set_bit(ETHTOOL_LINK_MODE_10000baseLRM_Full_BIT,
				  supported);
		if (val & MDIO_PMA_EXTABLE_10GBT)
			__set_bit(ETHTOOL_LINK_MODE_10000baseT_Full_BIT,
				  supported);
		if (val & MDIO_PMA_EXTABLE_10GBKX4)
			__set_bit(ETHTOOL_LINK_MODE_10000baseKX4_Full_BIT,
				  supported);
		if (val & MDIO_PMA_EXTABLE_10GBKR)
			__set_bit(ETHTOOL_LINK_MODE_10000baseKR_Full_BIT,
				  supported);
		if (val & MDIO_PMA_EXTABLE_1000BT)
			__set_bit(ETHTOOL_LINK_MODE_1000baseT_Full_BIT,
				  supported);
		if (val & MDIO_PMA_EXTABLE_1000BKX)
			__set_bit(ETHTOOL_LINK_MODE_1000baseKX_Full_BIT,
				  supported);
		if (val & MDIO_PMA_EXTABLE_100BTX)
			__set_bit(ETHTOOL_LINK_MODE_100baseT_Full_BIT,
				  supported);
		if (val & MDIO_PMA_EXTABLE_10BT)
			__set_bit(ETHTOOL_LINK_MODE_10baseT_Full_BIT,
				  supported);
	}

	if (!ethtool_convert_link_mode_to_legacy_u32(&mask, supported))
		dev_warn(&phydev->mdio.dev,
			 "PHY supports (%*pb) more modes than phylib supports, some modes not supported.\n",
			 __ETHTOOL_LINK_MODE_MASK_NBITS, supported);

	phydev->supported &= mask;
	phydev->advertising &= phydev->supported;

	/* Would be nice to do this in the probe function, but unfortunately,
	 * phylib doesn't have phydev->attached_dev set there.
	 */
	if (priv->sfp_node && !priv->sfp_bus)
		priv->sfp_bus = sfp_register_upstream(priv->sfp_node,
						      phydev->attached_dev,
						      phydev, &mv3310_sfp_ops);

	return 0;
}

static int mv3310_config_aneg(struct phy_device *phydev)
{
	bool changed = false;
	u32 advertising;
	int ret;

	if (phydev->autoneg == AUTONEG_DISABLE) {
		ret = genphy_c45_pma_setup_forced(phydev);
		if (ret < 0)
			return ret;

		return genphy_c45_an_disable_aneg(phydev);
	}

	phydev->advertising &= phydev->supported;
	advertising = phydev->advertising;

	ret = mv3310_modify(phydev, MDIO_MMD_AN, MDIO_AN_ADVERTISE,
			    ADVERTISE_ALL | ADVERTISE_100BASE4 |
			    ADVERTISE_PAUSE_CAP | ADVERTISE_PAUSE_ASYM,
			    ethtool_adv_to_mii_adv_t(advertising));
	if (ret < 0)
		return ret;
	if (ret > 0)
		changed = true;

	ret = mv3310_modify(phydev, MDIO_MMD_AN, MV_AN_CTRL1000,
			    ADVERTISE_1000FULL | ADVERTISE_1000HALF,
			    ethtool_adv_to_mii_ctrl1000_t(advertising));
	if (ret < 0)
		return ret;
	if (ret > 0)
		changed = true;

	/* 10G control register */
	ret = mv3310_modify(phydev, MDIO_MMD_AN, MDIO_AN_10GBT_CTRL,
			    MDIO_AN_10GBT_CTRL_ADV10G,
			    advertising & ADVERTISED_10000baseT_Full ?
				MDIO_AN_10GBT_CTRL_ADV10G : 0);
	if (ret < 0)
		return ret;
	if (ret > 0)
		changed = true;

	if (changed)
		ret = genphy_c45_restart_aneg(phydev);

	return ret;
}

static int mv3310_aneg_done(struct phy_device *phydev)
{
	int val;

	val = phy_read_mmd(phydev, MDIO_MMD_PCS, MV_PCS_BASE_R + MDIO_STAT1);
	if (val < 0)
		return val;

	if (val & MDIO_STAT1_LSTATUS)
		return 1;

	return genphy_c45_aneg_done(phydev);
}

/* 10GBASE-ER,LR,LRM,SR do not support autonegotiation. */
static int mv3310_read_10gbr_status(struct phy_device *phydev)
{
	phydev->link = 1;
	phydev->speed = SPEED_10000;
	phydev->duplex = DUPLEX_FULL;

	if (phydev->interface == PHY_INTERFACE_MODE_SGMII)
		phydev->interface = PHY_INTERFACE_MODE_10GKR;

	return 0;
}

static int mv3310_read_status(struct phy_device *phydev)
{
	u32 mmd_mask = phydev->c45_ids.devices_in_package;
	int val;

	/* The vendor devads do not report link status.  Avoid the PHYXS
	 * instance as there are three, and its status depends on the MAC
	 * being appropriately configured for the negotiated speed.
	 */
	mmd_mask &= ~(BIT(MDIO_MMD_VEND1) | BIT(MDIO_MMD_VEND2) |
		      BIT(MDIO_MMD_PHYXS));

	phydev->speed = SPEED_UNKNOWN;
	phydev->duplex = DUPLEX_UNKNOWN;
	phydev->lp_advertising = 0;
	phydev->link = 0;
	phydev->pause = 0;
	phydev->asym_pause = 0;

	val = phy_read_mmd(phydev, MDIO_MMD_PCS, MV_PCS_BASE_R + MDIO_STAT1);
	if (val < 0)
		return val;

	if (val & MDIO_STAT1_LSTATUS)
		return mv3310_read_10gbr_status(phydev);

	val = genphy_c45_read_link(phydev, mmd_mask);
	if (val < 0)
		return val;

	phydev->link = val > 0 ? 1 : 0;

	val = phy_read_mmd(phydev, MDIO_MMD_AN, MDIO_STAT1);
	if (val < 0)
		return val;

	if (val & MDIO_AN_STAT1_COMPLETE) {
		val = genphy_c45_read_lpa(phydev);
		if (val < 0)
			return val;

		/* Read the link partner's 1G advertisment */
		val = phy_read_mmd(phydev, MDIO_MMD_AN, MV_AN_STAT1000);
		if (val < 0)
			return val;

		phydev->lp_advertising |= mii_stat1000_to_ethtool_lpa_t(val);

		if (phydev->autoneg == AUTONEG_ENABLE) {
			val = phy_read_mmd(phydev, MDIO_MMD_AN, MV_AN_RESULT);
			if (val < 0)
				return val;

			if (val & MV_AN_RESULT_SPD_10000)
				phydev->speed = SPEED_10000;
			else if (val & MV_AN_RESULT_SPD_1000)
				phydev->speed = SPEED_1000;
			else if (val & MV_AN_RESULT_SPD_100)
				phydev->speed = SPEED_100;
			else if (val & MV_AN_RESULT_SPD_10)
				phydev->speed = SPEED_10;

			phydev->duplex = DUPLEX_FULL;
		}
	}

	if (phydev->autoneg != AUTONEG_ENABLE) {
		val = genphy_c45_read_pma(phydev);
		if (val < 0)
			return val;
	}

	if ((phydev->interface == PHY_INTERFACE_MODE_SGMII ||
	     phydev->interface == PHY_INTERFACE_MODE_10GKR) && phydev->link) {
		/* The PHY automatically switches its serdes interface (and
		 * active PHYXS instance) between Cisco SGMII and 10GBase-KR
		 * modes according to the speed.  Florian suggests setting
		 * phydev->interface to communicate this to the MAC. Only do
		 * this if we are already in either SGMII or 10GBase-KR mode.
		 */
		if (phydev->speed == SPEED_10000)
			phydev->interface = PHY_INTERFACE_MODE_10GKR;
		else if (phydev->speed >= SPEED_10 &&
			 phydev->speed < SPEED_10000)
			phydev->interface = PHY_INTERFACE_MODE_SGMII;
	}

	return 0;
}

static struct phy_driver mv3310_drivers[] = {
	{
		.phy_id		= 0x002b09aa,
		.phy_id_mask	= 0xffffffff,
		.name		= "mv88x3310",
		.features	= SUPPORTED_10baseT_Full |
				  SUPPORTED_100baseT_Full |
				  SUPPORTED_1000baseT_Full |
				  SUPPORTED_Autoneg |
				  SUPPORTED_TP |
				  SUPPORTED_FIBRE |
				  SUPPORTED_10000baseT_Full |
				  SUPPORTED_Backplane,
		.soft_reset	= mv3310_soft_reset,
		.config_init	= mv3310_config_init,
		.probe		= mv3310_probe,
		.config_aneg	= mv3310_config_aneg,
		.aneg_done	= mv3310_aneg_done,
		.read_status	= mv3310_read_status,
		.remove		= mv3310_remove,
	},
};

module_phy_driver(mv3310_drivers);

static struct mdio_device_id __maybe_unused mv3310_tbl[] = {
	{ 0x002b09aa, 0xffffffff },
	{ },
};
MODULE_DEVICE_TABLE(mdio, mv3310_tbl);
MODULE_DESCRIPTION("Marvell Alaska X 10Gigabit Ethernet PHY driver (MV88X3310)");
MODULE_LICENSE("GPL");