// 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 #include #include enum { MDIO_AN_C22 = 0xffe0, }; static int bcm84881_wait_init(struct phy_device *phydev) { int val; return phy_read_mmd_poll_timeout(phydev, MDIO_MMD_PMAPMD, MDIO_CTRL1, val, !(val & MDIO_CTRL1_RESET), 100000, 2000000, false); } 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_10GBASER: 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 bcm84881_get_features(struct phy_device *phydev) { int ret; ret = genphy_c45_pma_read_abilities(phydev); if (ret) return ret; /* Although the PHY sets bit 1.11.8, it does not support 10M modes */ linkmode_clear_bit(ETHTOOL_LINK_MODE_10baseT_Half_BIT, phydev->supported); linkmode_clear_bit(ETHTOOL_LINK_MODE_10baseT_Full_BIT, phydev->supported); return 0; } 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 = linkmode_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) { 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; phydev->autoneg_complete = !!(val & MDIO_AN_STAT1_COMPLETE) && !!(bmsr & BMSR_ANEGCOMPLETE); phydev->link = !!(val & MDIO_STAT1_LSTATUS) && !!(bmsr & BMSR_LSTATUS); if (phydev->autoneg == AUTONEG_ENABLE && !phydev->autoneg_complete) phydev->link = false; linkmode_zero(phydev->lp_advertising); phydev->speed = SPEED_UNKNOWN; phydev->duplex = DUPLEX_UNKNOWN; phydev->pause = 0; phydev->asym_pause = 0; phydev->mdix = 0; if (!phydev->link) return 0; if (phydev->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; mii_stat1000_mod_linkmode_lpa_t(phydev->lp_advertising, 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_10GBASER; 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", .config_init = bcm84881_config_init, .probe = bcm84881_probe, .get_features = bcm84881_get_features, .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");