diff options
Diffstat (limited to 'drivers/net/phy/dp83tg720.c')
-rw-r--r-- | drivers/net/phy/dp83tg720.c | 188 |
1 files changed, 188 insertions, 0 deletions
diff --git a/drivers/net/phy/dp83tg720.c b/drivers/net/phy/dp83tg720.c new file mode 100644 index 0000000000..326c9770a6 --- /dev/null +++ b/drivers/net/phy/dp83tg720.c @@ -0,0 +1,188 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Driver for the Texas Instruments DP83TG720 PHY + * Copyright (c) 2023 Pengutronix, Oleksij Rempel <kernel@pengutronix.de> + */ +#include <linux/bitfield.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/phy.h> + +#define DP83TG720S_PHY_ID 0x2000a284 + +/* MDIO_MMD_VEND2 registers */ +#define DP83TG720S_MII_REG_10 0x10 +#define DP83TG720S_STS_MII_INT BIT(7) +#define DP83TG720S_LINK_STATUS BIT(0) + +#define DP83TG720S_PHY_RESET 0x1f +#define DP83TG720S_HW_RESET BIT(15) + +#define DP83TG720S_RGMII_DELAY_CTRL 0x602 +/* In RGMII mode, Enable or disable the internal delay for RXD */ +#define DP83TG720S_RGMII_RX_CLK_SEL BIT(1) +/* In RGMII mode, Enable or disable the internal delay for TXD */ +#define DP83TG720S_RGMII_TX_CLK_SEL BIT(0) + +#define DP83TG720S_SQI_REG_1 0x871 +#define DP83TG720S_SQI_OUT_WORST GENMASK(7, 5) +#define DP83TG720S_SQI_OUT GENMASK(3, 1) + +#define DP83TG720_SQI_MAX 7 + +static int dp83tg720_config_aneg(struct phy_device *phydev) +{ + /* Autoneg is not supported and this PHY supports only one speed. + * We need to care only about master/slave configuration if it was + * changed by user. + */ + return genphy_c45_pma_baset1_setup_master_slave(phydev); +} + +static int dp83tg720_read_status(struct phy_device *phydev) +{ + u16 phy_sts; + int ret; + + phydev->pause = 0; + phydev->asym_pause = 0; + + /* Most of Clause 45 registers are not present, so we can't use + * genphy_c45_read_status() here. + */ + phy_sts = phy_read(phydev, DP83TG720S_MII_REG_10); + phydev->link = !!(phy_sts & DP83TG720S_LINK_STATUS); + if (!phydev->link) { + /* According to the "DP83TC81x, DP83TG72x Software + * Implementation Guide", the PHY needs to be reset after a + * link loss or if no link is created after at least 100ms. + * + * Currently we are polling with the PHY_STATE_TIME (1000ms) + * interval, which is still enough for not automotive use cases. + */ + ret = phy_init_hw(phydev); + if (ret) + return ret; + + /* After HW reset we need to restore master/slave configuration. + */ + ret = dp83tg720_config_aneg(phydev); + if (ret) + return ret; + + phydev->speed = SPEED_UNKNOWN; + phydev->duplex = DUPLEX_UNKNOWN; + } else { + /* PMA/PMD control 1 register (Register 1.0) is present, but it + * doesn't contain the link speed information. + * So genphy_c45_read_pma() can't be used here. + */ + ret = genphy_c45_pma_baset1_read_master_slave(phydev); + if (ret) + return ret; + + phydev->duplex = DUPLEX_FULL; + phydev->speed = SPEED_1000; + } + + return 0; +} + +static int dp83tg720_get_sqi(struct phy_device *phydev) +{ + int ret; + + if (!phydev->link) + return 0; + + ret = phy_read_mmd(phydev, MDIO_MMD_VEND2, DP83TG720S_SQI_REG_1); + if (ret < 0) + return ret; + + return FIELD_GET(DP83TG720S_SQI_OUT, ret); +} + +static int dp83tg720_get_sqi_max(struct phy_device *phydev) +{ + return DP83TG720_SQI_MAX; +} + +static int dp83tg720_config_rgmii_delay(struct phy_device *phydev) +{ + u16 rgmii_delay_mask; + u16 rgmii_delay = 0; + + switch (phydev->interface) { + case PHY_INTERFACE_MODE_RGMII: + rgmii_delay = 0; + break; + case PHY_INTERFACE_MODE_RGMII_ID: + rgmii_delay = DP83TG720S_RGMII_RX_CLK_SEL | + DP83TG720S_RGMII_TX_CLK_SEL; + break; + case PHY_INTERFACE_MODE_RGMII_RXID: + rgmii_delay = DP83TG720S_RGMII_RX_CLK_SEL; + break; + case PHY_INTERFACE_MODE_RGMII_TXID: + rgmii_delay = DP83TG720S_RGMII_TX_CLK_SEL; + break; + default: + return 0; + } + + rgmii_delay_mask = DP83TG720S_RGMII_RX_CLK_SEL | + DP83TG720S_RGMII_TX_CLK_SEL; + + return phy_modify_mmd(phydev, MDIO_MMD_VEND2, + DP83TG720S_RGMII_DELAY_CTRL, rgmii_delay_mask, + rgmii_delay); +} + +static int dp83tg720_config_init(struct phy_device *phydev) +{ + int ret; + + /* Software Restart is not enough to recover from a link failure. + * Using Hardware Reset instead. + */ + ret = phy_write(phydev, DP83TG720S_PHY_RESET, DP83TG720S_HW_RESET); + if (ret) + return ret; + + /* Wait until MDC can be used again. + * The wait value of one 1ms is documented in "DP83TG720S-Q1 1000BASE-T1 + * Automotive Ethernet PHY with SGMII and RGMII" datasheet. + */ + usleep_range(1000, 2000); + + if (phy_interface_is_rgmii(phydev)) + return dp83tg720_config_rgmii_delay(phydev); + + return 0; +} + +static struct phy_driver dp83tg720_driver[] = { +{ + PHY_ID_MATCH_MODEL(DP83TG720S_PHY_ID), + .name = "TI DP83TG720S", + + .config_aneg = dp83tg720_config_aneg, + .read_status = dp83tg720_read_status, + .get_features = genphy_c45_pma_read_ext_abilities, + .config_init = dp83tg720_config_init, + .get_sqi = dp83tg720_get_sqi, + .get_sqi_max = dp83tg720_get_sqi_max, + + .suspend = genphy_suspend, + .resume = genphy_resume, +} }; +module_phy_driver(dp83tg720_driver); + +static struct mdio_device_id __maybe_unused dp83tg720_tbl[] = { + { PHY_ID_MATCH_MODEL(DP83TG720S_PHY_ID) }, + { } +}; +MODULE_DEVICE_TABLE(mdio, dp83tg720_tbl); + +MODULE_DESCRIPTION("Texas Instruments DP83TG720S PHY driver"); +MODULE_AUTHOR("Oleksij Rempel <kernel@pengutronix.de>"); +MODULE_LICENSE("GPL"); |