| // SPDX-License-Identifier: GPL-2.0 | 
 | // Broadcom BCM84881 NBASE-T PHY driver, as found on a SFP+ module. | 
 | // Copyright (C) 2019 Russell King, Deep Blue Solutions Ltd. | 
 | // | 
 | // Like the Marvell 88x3310, the Broadcom 84881 changes its host-side | 
 | // interface according to the operating speed between 10GBASE-R, | 
 | // 2500BASE-X and SGMII (but unlike the 88x3310, without the control | 
 | // word). | 
 | // | 
 | // This driver only supports those aspects of the PHY that I'm able to | 
 | // observe and test with the SFP+ module, which is an incomplete subset | 
 | // of what this PHY is able to support. For example, I only assume it | 
 | // supports a single lane Serdes connection, but it may be that the PHY | 
 | // is able to support more than that. | 
 | #include <linux/delay.h> | 
 | #include <linux/module.h> | 
 | #include <linux/phy.h> | 
 |  | 
 | enum { | 
 | 	MDIO_AN_C22 = 0xffe0, | 
 | }; | 
 |  | 
 | static int bcm84881_wait_init(struct phy_device *phydev) | 
 | { | 
 | 	unsigned int tries = 20; | 
 | 	int ret, val; | 
 |  | 
 | 	do { | 
 | 		val = phy_read_mmd(phydev, MDIO_MMD_PMAPMD, MDIO_CTRL1); | 
 | 		if (val < 0) { | 
 | 			ret = val; | 
 | 			break; | 
 | 		} | 
 | 		if (!(val & MDIO_CTRL1_RESET)) { | 
 | 			ret = 0; | 
 | 			break; | 
 | 		} | 
 | 		if (!--tries) { | 
 | 			ret = -ETIMEDOUT; | 
 | 			break; | 
 | 		} | 
 | 		msleep(100); | 
 | 	} while (1); | 
 |  | 
 | 	if (ret) | 
 | 		phydev_err(phydev, "%s failed: %d\n", __func__, ret); | 
 |  | 
 | 	return ret; | 
 | } | 
 |  | 
 | static int bcm84881_config_init(struct phy_device *phydev) | 
 | { | 
 | 	switch (phydev->interface) { | 
 | 	case PHY_INTERFACE_MODE_SGMII: | 
 | 	case PHY_INTERFACE_MODE_2500BASEX: | 
 | 	case PHY_INTERFACE_MODE_10GKR: | 
 | 		break; | 
 | 	default: | 
 | 		return -ENODEV; | 
 | 	} | 
 | 	return 0; | 
 | } | 
 |  | 
 | static int bcm84881_probe(struct phy_device *phydev) | 
 | { | 
 | 	/* This driver requires PMAPMD and AN blocks */ | 
 | 	const 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; | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | static int genphy_c45_an_config_aneg(struct phy_device *phydev) | 
 | { | 
 | 	bool changed = false; | 
 | 	u32 advertising; | 
 | 	int ret; | 
 |  | 
 | 	phydev->advertising &= phydev->supported; | 
 | 	advertising = phydev->advertising; | 
 |  | 
 | 	ret = phy_modify_mmd_changed(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 = phy_modify_mmd_changed(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; | 
 |  | 
 | 	return genphy_c45_check_and_restart_aneg(phydev, changed); | 
 | } | 
 |  | 
 | static int bcm84881_config_aneg(struct phy_device *phydev) | 
 | { | 
 | 	bool changed = false; | 
 | 	u32 adv; | 
 | 	int ret; | 
 |  | 
 | 	/* Wait for the PHY to finish initialising, otherwise our | 
 | 	 * advertisement may be overwritten. | 
 | 	 */ | 
 | 	ret = bcm84881_wait_init(phydev); | 
 | 	if (ret) | 
 | 		return ret; | 
 |  | 
 | 	/* We don't support manual MDI control */ | 
 | 	phydev->mdix_ctrl = ETH_TP_MDI_AUTO; | 
 |  | 
 | 	/* disabled autoneg doesn't seem to work with this PHY */ | 
 | 	if (phydev->autoneg == AUTONEG_DISABLE) | 
 | 		return -EINVAL; | 
 |  | 
 | 	ret = genphy_c45_an_config_aneg(phydev); | 
 | 	if (ret < 0) | 
 | 		return ret; | 
 | 	if (ret > 0) | 
 | 		changed = true; | 
 |  | 
 | 	adv = ethtool_adv_to_mii_ctrl1000_t(phydev->advertising); | 
 | 	ret = phy_modify_mmd_changed(phydev, MDIO_MMD_AN, | 
 | 				     MDIO_AN_C22 + MII_CTRL1000, | 
 | 				     ADVERTISE_1000FULL | ADVERTISE_1000HALF, | 
 | 				     adv); | 
 | 	if (ret < 0) | 
 | 		return ret; | 
 | 	if (ret > 0) | 
 | 		changed = true; | 
 |  | 
 | 	return genphy_c45_check_and_restart_aneg(phydev, changed); | 
 | } | 
 |  | 
 | static int bcm84881_aneg_done(struct phy_device *phydev) | 
 | { | 
 | 	int bmsr, val; | 
 |  | 
 | 	val = phy_read_mmd(phydev, MDIO_MMD_AN, MDIO_STAT1); | 
 | 	if (val < 0) | 
 | 		return val; | 
 |  | 
 | 	bmsr = phy_read_mmd(phydev, MDIO_MMD_AN, MDIO_AN_C22 + MII_BMSR); | 
 | 	if (bmsr < 0) | 
 | 		return val; | 
 |  | 
 | 	return !!(val & MDIO_AN_STAT1_COMPLETE) && | 
 | 	       !!(bmsr & BMSR_ANEGCOMPLETE); | 
 | } | 
 |  | 
 | static int bcm84881_read_status(struct phy_device *phydev) | 
 | { | 
 | 	bool autoneg_complete; | 
 | 	unsigned int mode; | 
 | 	int bmsr, val; | 
 |  | 
 | 	val = phy_read_mmd(phydev, MDIO_MMD_AN, MDIO_CTRL1); | 
 | 	if (val < 0) | 
 | 		return val; | 
 |  | 
 | 	if (val & MDIO_AN_CTRL1_RESTART) { | 
 | 		phydev->link = 0; | 
 | 		return 0; | 
 | 	} | 
 |  | 
 | 	val = phy_read_mmd(phydev, MDIO_MMD_AN, MDIO_STAT1); | 
 | 	if (val < 0) | 
 | 		return val; | 
 |  | 
 | 	bmsr = phy_read_mmd(phydev, MDIO_MMD_AN, MDIO_AN_C22 + MII_BMSR); | 
 | 	if (bmsr < 0) | 
 | 		return val; | 
 |  | 
 | 	autoneg_complete = !!(val & MDIO_AN_STAT1_COMPLETE) && | 
 | 			   !!(bmsr & BMSR_ANEGCOMPLETE); | 
 | 	phydev->link = !!(val & MDIO_STAT1_LSTATUS) && | 
 | 		       !!(bmsr & BMSR_LSTATUS); | 
 | 	if (phydev->autoneg == AUTONEG_ENABLE && !autoneg_complete) | 
 | 		phydev->link = false; | 
 |  | 
 | 	if (!phydev->link) | 
 | 		return 0; | 
 |  | 
 | 	phydev->lp_advertising = 0; | 
 | 	phydev->speed = SPEED_UNKNOWN; | 
 | 	phydev->duplex = DUPLEX_UNKNOWN; | 
 | 	phydev->pause = 0; | 
 | 	phydev->asym_pause = 0; | 
 | 	phydev->mdix = 0; | 
 |  | 
 | 	if (autoneg_complete) { | 
 | 		val = genphy_c45_read_lpa(phydev); | 
 | 		if (val < 0) | 
 | 			return val; | 
 |  | 
 | 		val = phy_read_mmd(phydev, MDIO_MMD_AN, | 
 | 				   MDIO_AN_C22 + MII_STAT1000); | 
 | 		if (val < 0) | 
 | 			return val; | 
 |  | 
 | 		phydev->lp_advertising |= mii_stat1000_to_ethtool_lpa_t(val); | 
 |  | 
 | 		if (phydev->autoneg == AUTONEG_ENABLE) | 
 | 			phy_resolve_aneg_linkmode(phydev); | 
 | 	} | 
 |  | 
 | 	if (phydev->autoneg == AUTONEG_DISABLE) { | 
 | 		/* disabled autoneg doesn't seem to work, so force the link | 
 | 		 * down. | 
 | 		 */ | 
 | 		phydev->link = 0; | 
 | 		return 0; | 
 | 	} | 
 |  | 
 | 	/* Set the host link mode - we set the phy interface mode and | 
 | 	 * the speed according to this register so that downshift works. | 
 | 	 * We leave the duplex setting as per the resolution from the | 
 | 	 * above. | 
 | 	 */ | 
 | 	val = phy_read_mmd(phydev, MDIO_MMD_VEND1, 0x4011); | 
 | 	mode = (val & 0x1e) >> 1; | 
 | 	if (mode == 1 || mode == 2) | 
 | 		phydev->interface = PHY_INTERFACE_MODE_SGMII; | 
 | 	else if (mode == 3) | 
 | 		phydev->interface = PHY_INTERFACE_MODE_10GKR; | 
 | 	else if (mode == 4) | 
 | 		phydev->interface = PHY_INTERFACE_MODE_2500BASEX; | 
 | 	switch (mode & 7) { | 
 | 	case 1: | 
 | 		phydev->speed = SPEED_100; | 
 | 		break; | 
 | 	case 2: | 
 | 		phydev->speed = SPEED_1000; | 
 | 		break; | 
 | 	case 3: | 
 | 		phydev->speed = SPEED_10000; | 
 | 		break; | 
 | 	case 4: | 
 | 		phydev->speed = SPEED_2500; | 
 | 		break; | 
 | 	case 5: | 
 | 		phydev->speed = SPEED_5000; | 
 | 		break; | 
 | 	} | 
 |  | 
 | 	return genphy_c45_read_mdix(phydev); | 
 | } | 
 |  | 
 | static struct phy_driver bcm84881_drivers[] = { | 
 | 	{ | 
 | 		.phy_id		= 0xae025150, | 
 | 		.phy_id_mask	= 0xfffffff0, | 
 | 		.name		= "Broadcom BCM84881", | 
 | 		.features	= SUPPORTED_100baseT_Full | | 
 | 				  SUPPORTED_100baseT_Half | | 
 | 				  SUPPORTED_1000baseT_Full | | 
 | 				  SUPPORTED_Autoneg | | 
 | 				  SUPPORTED_TP | | 
 | 				  SUPPORTED_FIBRE | | 
 | 				  SUPPORTED_10000baseT_Full | | 
 | 				  SUPPORTED_Backplane, | 
 | 		.config_init	= bcm84881_config_init, | 
 | 		.probe		= bcm84881_probe, | 
 | 		.config_aneg	= bcm84881_config_aneg, | 
 | 		.aneg_done	= bcm84881_aneg_done, | 
 | 		.read_status	= bcm84881_read_status, | 
 | 	}, | 
 | }; | 
 |  | 
 | module_phy_driver(bcm84881_drivers); | 
 |  | 
 | /* FIXME: module auto-loading for Clause 45 PHYs seems non-functional */ | 
 | static struct mdio_device_id __maybe_unused bcm84881_tbl[] = { | 
 | 	{ 0xae025150, 0xfffffff0 }, | 
 | 	{ }, | 
 | }; | 
 | MODULE_AUTHOR("Russell King"); | 
 | MODULE_DESCRIPTION("Broadcom BCM84881 PHY driver"); | 
 | MODULE_DEVICE_TABLE(mdio, bcm84881_tbl); | 
 | MODULE_LICENSE("GPL"); |