diff options
Diffstat (limited to 'drivers/net/phy/bcm84881.c')
| -rw-r--r-- | drivers/net/phy/bcm84881.c | 250 |
1 files changed, 250 insertions, 0 deletions
diff --git a/drivers/net/phy/bcm84881.c b/drivers/net/phy/bcm84881.c new file mode 100644 index 000000000..9717a1626 --- /dev/null +++ b/drivers/net/phy/bcm84881.c @@ -0,0 +1,250 @@ +// 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) +{ + 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"); |