From: Oleksij Rempel Date: Wed, 18 Jun 2025 12:26:01 +0000 (+0200) Subject: net: usb: lan78xx: Integrate EEE support with phylink LPI API X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=673d455bbb1db1b242c502ef551d4cc8f45b00ce;p=thirdparty%2Flinux.git net: usb: lan78xx: Integrate EEE support with phylink LPI API Refactor Energy-Efficient Ethernet (EEE) support in the LAN78xx driver to fully integrate with the phylink Low Power Idle (LPI) API. This includes: - Replacing direct calls to `phy_ethtool_get_eee` and `phy_ethtool_set_eee` with `phylink_ethtool_get_eee` and `phylink_ethtool_set_eee`. - Implementing `.mac_enable_tx_lpi` and `.mac_disable_tx_lpi` to control LPI transitions via phylink. - Configuring `lpi_timer_default` to align with recommended values from LAN7800 documentation. - ensure EEE is disabled on controller reset Signed-off-by: Oleksij Rempel Reviewed-by: Russell King (Oracle) Link: https://patch.msgid.link/20250618122602.3156678-6-o.rempel@pengutronix.de Signed-off-by: Jakub Kicinski --- diff --git a/drivers/net/usb/lan78xx.c b/drivers/net/usb/lan78xx.c index 8df0a2323fb9a..3bff1e72a89f5 100644 --- a/drivers/net/usb/lan78xx.c +++ b/drivers/net/usb/lan78xx.c @@ -1789,54 +1789,15 @@ exit_pm_put: static int lan78xx_get_eee(struct net_device *net, struct ethtool_keee *edata) { struct lan78xx_net *dev = netdev_priv(net); - struct phy_device *phydev = net->phydev; - int ret; - u32 buf; - - ret = usb_autopm_get_interface(dev->intf); - if (ret < 0) - return ret; - - ret = phy_ethtool_get_eee(phydev, edata); - if (ret < 0) - goto exit; - ret = lan78xx_read_reg(dev, MAC_CR, &buf); - if (buf & MAC_CR_EEE_EN_) { - /* EEE_TX_LPI_REQ_DLY & tx_lpi_timer are same uSec unit */ - ret = lan78xx_read_reg(dev, EEE_TX_LPI_REQ_DLY, &buf); - edata->tx_lpi_timer = buf; - } else { - edata->tx_lpi_timer = 0; - } - - ret = 0; -exit: - usb_autopm_put_interface(dev->intf); - - return ret; + return phylink_ethtool_get_eee(dev->phylink, edata); } static int lan78xx_set_eee(struct net_device *net, struct ethtool_keee *edata) { struct lan78xx_net *dev = netdev_priv(net); - int ret; - u32 buf; - - ret = usb_autopm_get_interface(dev->intf); - if (ret < 0) - return ret; - ret = phy_ethtool_set_eee(net->phydev, edata); - if (ret < 0) - goto out; - - buf = (u32)edata->tx_lpi_timer; - ret = lan78xx_write_reg(dev, EEE_TX_LPI_REQ_DLY, buf); -out: - usb_autopm_put_interface(dev->intf); - - return ret; + return phylink_ethtool_set_eee(dev->phylink, edata); } static void lan78xx_get_drvinfo(struct net_device *net, @@ -2557,10 +2518,62 @@ link_up_fail: ERR_PTR(ret)); } +/** + * lan78xx_mac_eee_enable - Enable or disable MAC-side EEE support + * @dev: LAN78xx device + * @enable: true to enable EEE, false to disable + * + * This function sets or clears the MAC_CR_EEE_EN_ bit to control Energy + * Efficient Ethernet (EEE) operation. According to current understanding + * of the LAN7800 documentation, this bit can be modified while TX and RX + * are enabled. No explicit requirement was found to disable data paths + * before changing this bit. + * + * Return: 0 on success or a negative error code + */ +static int lan78xx_mac_eee_enable(struct lan78xx_net *dev, bool enable) +{ + u32 mac_cr = 0; + + if (enable) + mac_cr |= MAC_CR_EEE_EN_; + + return lan78xx_update_reg(dev, MAC_CR, MAC_CR_EEE_EN_, mac_cr); +} + +static void lan78xx_mac_disable_tx_lpi(struct phylink_config *config) +{ + struct net_device *net = to_net_dev(config->dev); + struct lan78xx_net *dev = netdev_priv(net); + + lan78xx_mac_eee_enable(dev, false); +} + +static int lan78xx_mac_enable_tx_lpi(struct phylink_config *config, u32 timer, + bool tx_clk_stop) +{ + struct net_device *net = to_net_dev(config->dev); + struct lan78xx_net *dev = netdev_priv(net); + int ret; + + /* Software should only change this field when Energy Efficient + * Ethernet Enable (EEEEN) is cleared. We ensure that by clearing + * EEEEN during probe, and phylink itself guarantees that + * mac_disable_tx_lpi() will have been previously called. + */ + ret = lan78xx_write_reg(dev, EEE_TX_LPI_REQ_DLY, timer); + if (ret < 0) + return ret; + + return lan78xx_mac_eee_enable(dev, true); +} + static const struct phylink_mac_ops lan78xx_phylink_mac_ops = { .mac_config = lan78xx_mac_config, .mac_link_down = lan78xx_mac_link_down, .mac_link_up = lan78xx_mac_link_up, + .mac_disable_tx_lpi = lan78xx_mac_disable_tx_lpi, + .mac_enable_tx_lpi = lan78xx_mac_enable_tx_lpi, }; /** @@ -2756,12 +2769,36 @@ static int lan78xx_phylink_setup(struct lan78xx_net *dev) pc->mac_capabilities = MAC_SYM_PAUSE | MAC_ASYM_PAUSE | MAC_10 | MAC_100 | MAC_1000FD; pc->mac_managed_pm = true; + pc->lpi_capabilities = MAC_100FD | MAC_1000FD; + /* + * Default TX LPI (Low Power Idle) request delay count is set to 50us. + * + * Source: LAN7800 Documentation, DS00001992H, Section 15.1.57, Page 204. + * + * Reasoning: + * According to the application note in the LAN7800 documentation, a + * zero delay may negatively impact the TX data path’s ability to + * support Gigabit operation. A value of 50us is recommended as a + * reasonable default when the part operates at Gigabit speeds, + * balancing stability and power efficiency in EEE mode. This delay can + * be increased based on performance testing, as EEE is designed for + * scenarios with mostly idle links and occasional bursts of full + * bandwidth transmission. The goal is to ensure reliable Gigabit + * performance without overly aggressive power optimization during + * inactive periods. + */ + pc->lpi_timer_default = 50; + pc->eee_enabled_default = true; if (dev->chipid == ID_REV_CHIP_ID_7801_) phy_interface_set_rgmii(pc->supported_interfaces); else __set_bit(PHY_INTERFACE_MODE_GMII, pc->supported_interfaces); + memcpy(dev->phylink_config.lpi_interfaces, + dev->phylink_config.supported_interfaces, + sizeof(dev->phylink_config.lpi_interfaces)); + phylink = phylink_create(pc, dev->net->dev.fwnode, dev->interface, &lan78xx_phylink_mac_ops); if (IS_ERR(phylink)) @@ -2827,8 +2864,6 @@ static int lan78xx_phy_init(struct lan78xx_net *dev) goto phylink_uninit; } - phy_support_eee(phydev); - ret = lan78xx_configure_leds_from_dt(dev, phydev); if (ret < 0) goto phylink_uninit; @@ -3333,7 +3368,7 @@ static int lan78xx_reset(struct lan78xx_net *dev) if (ret < 0) return ret; - buf &= ~(MAC_CR_AUTO_DUPLEX_ | MAC_CR_AUTO_SPEED_); + buf &= ~(MAC_CR_AUTO_DUPLEX_ | MAC_CR_AUTO_SPEED_ | MAC_CR_EEE_EN_); /* LAN7801 only has RGMII mode */ if (dev->chipid == ID_REV_CHIP_ID_7801_)