From 6fdc64ef7abea4b39ace5c25564ee50a49e7e403 Mon Sep 17 00:00:00 2001 From: Russell King Date: Mon, 9 Dec 2019 23:13:51 +0000 Subject: net: add helpers to resolve negotiated flow control Add a couple of helpers to resolve negotiated flow control. Two helpers are provided: - linkmode_resolve_pause() which takes the link partner and local advertisements, and decodes whether we should enable TX or RX pause at the MAC. This is useful outside of phylib, e.g. in phylink. - phy_get_pause(), which returns the TX/RX enablement status for the current negotiation results of the PHY. This allows us to centralise the flow control resolution, rather than spreading it around. Signed-off-by: Russell King --- drivers/net/phy/Makefile | 3 ++- drivers/net/phy/linkmode.c | 44 ++++++++++++++++++++++++++++++++++++++++++++ drivers/net/phy/phy_device.c | 26 ++++++++++++++++++++++++++ include/linux/linkmode.h | 4 ++++ include/linux/phy.h | 3 +++ 5 files changed, 79 insertions(+), 1 deletion(-) create mode 100644 drivers/net/phy/linkmode.c diff --git a/drivers/net/phy/Makefile b/drivers/net/phy/Makefile index d846b4dc1c68..bd7367de6d69 100644 --- a/drivers/net/phy/Makefile +++ b/drivers/net/phy/Makefile @@ -1,7 +1,8 @@ # SPDX-License-Identifier: GPL-2.0 # Makefile for Linux PHY drivers and MDIO bus drivers -libphy-y := phy.o phy-c45.o phy-core.o phy_device.o +libphy-y := phy.o phy-c45.o phy-core.o phy_device.o \ + linkmode.o mdio-bus-y += mdio_bus.o mdio_device.o ifdef CONFIG_MDIO_DEVICE diff --git a/drivers/net/phy/linkmode.c b/drivers/net/phy/linkmode.c new file mode 100644 index 000000000000..969918795228 --- /dev/null +++ b/drivers/net/phy/linkmode.c @@ -0,0 +1,44 @@ +// SPDX-License-Identifier: GPL-2.0+ +#include + +/** + * linkmode_resolve_pause - resolve the allowable pause modes + * @local_adv: local advertisement in ethtool format + * @partner_adv: partner advertisement in ethtool format + * @tx_pause: pointer to bool to indicate whether transmit pause should be + * enabled. + * @rx_pause: pointer to bool to indicate whether receive pause should be + * enabled. + * + * Flow control is resolved according to our and the link partners + * advertisements using the following drawn from the 802.3 specs: + * Local device Link partner + * Pause AsymDir Pause AsymDir Result + * 0 X 0 X Disabled + * 0 1 1 0 Disabled + * 0 1 1 1 TX + * 1 0 0 X Disabled + * 1 X 1 X TX+RX + * 1 1 0 1 RX + */ +void linkmode_resolve_pause(const unsigned long *local_adv, + const unsigned long *partner_adv, + bool *tx_pause, bool *rx_pause) +{ + __ETHTOOL_DECLARE_LINK_MODE_MASK(m); + + linkmode_and(m, local_adv, partner_adv); + if (linkmode_test_bit(ETHTOOL_LINK_MODE_Pause_BIT, m)) { + *tx_pause = true; + *rx_pause = true; + } else if (linkmode_test_bit(ETHTOOL_LINK_MODE_Asym_Pause_BIT, m)) { + *tx_pause = linkmode_test_bit(ETHTOOL_LINK_MODE_Pause_BIT, + partner_adv); + *rx_pause = linkmode_test_bit(ETHTOOL_LINK_MODE_Pause_BIT, + local_adv); + } else { + *tx_pause = false; + *rx_pause = false; + } +} +EXPORT_SYMBOL_GPL(linkmode_resolve_pause); diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c index 2e23ed762111..a59bf4bd6cd3 100644 --- a/drivers/net/phy/phy_device.c +++ b/drivers/net/phy/phy_device.c @@ -2404,6 +2404,32 @@ bool phy_validate_pause(struct phy_device *phydev, } EXPORT_SYMBOL(phy_validate_pause); +/** + * phy_get_pause - resolve negotiated pause modes + * @phydev: phy_device struct + * @tx_pause: pointer to bool to indicate whether transmit pause should be + * enabled. + * @rx_pause: pointer to bool to indicate whether receive pause should be + * enabled. + * + * Resolve and return the flow control modes according to the negotiation + * result. This includes checking that we are operating in full duplex mode. + * See linkmode_resolve_pause() for further details. + */ +void phy_get_pause(struct phy_device *phydev, bool *tx_pause, bool *rx_pause) +{ + if (phydev->duplex != DUPLEX_FULL) { + *tx_pause = false; + *rx_pause = false; + return; + } + + return linkmode_resolve_pause(phydev->advertising, + phydev->lp_advertising, + tx_pause, rx_pause); +} +EXPORT_SYMBOL(phy_get_pause); + static bool phy_drv_supports_irq(struct phy_driver *phydrv) { return phydrv->config_intr && phydrv->ack_interrupt; diff --git a/include/linux/linkmode.h b/include/linux/linkmode.h index 8e5b352e44f2..9ec210f31d06 100644 --- a/include/linux/linkmode.h +++ b/include/linux/linkmode.h @@ -88,4 +88,8 @@ static inline int linkmode_subset(const unsigned long *src1, return bitmap_subset(src1, src2, __ETHTOOL_LINK_MODE_MASK_NBITS); } +void linkmode_resolve_pause(const unsigned long *local_adv, + const unsigned long *partner_adv, + bool *tx_pause, bool *rx_pause); + #endif /* __LINKMODE_H */ diff --git a/include/linux/phy.h b/include/linux/phy.h index 8492aaa97d0a..398aab718114 100644 --- a/include/linux/phy.h +++ b/include/linux/phy.h @@ -1196,6 +1196,9 @@ void phy_set_sym_pause(struct phy_device *phydev, bool rx, bool tx, void phy_set_asym_pause(struct phy_device *phydev, bool rx, bool tx); bool phy_validate_pause(struct phy_device *phydev, struct ethtool_pauseparam *pp); +void phy_get_pause(struct phy_device *phydev, bool *tx_pause, bool *rx_pause); +void phy_resolve_pause(unsigned long *local_adv, unsigned long *partner_adv, + bool *tx_pause, bool *rx_pause); int phy_register_fixup(const char *bus_id, u32 phy_uid, u32 phy_uid_mask, int (*run)(struct phy_device *)); -- cgit