Merge branch 'net-Add-support-for-Synopsys-DesignWare-XPCS'

Jose Abreu says:

====================
net: Add support for Synopsys DesignWare XPCS

This adds support for Synopsys DesignWare XPCS in net subsystem and
integrates it into stmmac.

At 1/8, we start by removing the limitation of stmmac selftests that needed
a PHY to pass all the tests.

Then at 2/8 we use some helpers in stmmac so that some code can be
simplified.

At 3/8, we fallback to dev_fwnode() so that PCI based setups wich may
not have CONFIG_OF can still use FW node.

At 4/8, we adapt stmmac to the new PHYLINK changes as suggested by Russell
King.

We proceed by doing changes in PHYLINK in order to support XPCS: At 5/8 we
add some missing speeds that USXGMII supports and at 6/8 we check if
Autoneg is supported after initial parameters are validated.

Support for XPCS is finally introduced at 7/8, along with the usage of it
in stmmac driver at 8/8.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

MAINTAINERS

@@ -16117,6 +16117,13 @@ L:	netdev@vger.kernel.org
 S:	Supported
 F:	drivers/net/ethernet/synopsys/
 
+SYNOPSYS DESIGNWARE ETHERNET XPCS DRIVER
+M:	Jose Abreu <Jose.Abreu@synopsys.com>
+L:	netdev@vger.kernel.org
+S:	Supported
+F:	drivers/net/phy/mdio-xpcs.c
+F:	include/linux/mdio-xpcs.h
+
 SYNOPSYS DESIGNWARE I2C DRIVER
 M:	Jarkko Nikula <jarkko.nikula@linux.intel.com>
 R:	Andy Shevchenko <andriy.shevchenko@linux.intel.com>

drivers/net/ethernet/stmicro/stmmac/Kconfig

@@ -3,6 +3,7 @@ config STMMAC_ETH
 	tristate "STMicroelectronics Multi-Gigabit Ethernet driver"
 	depends on HAS_IOMEM && HAS_DMA
 	select MII
+	select MDIO_XPCS
 	select PAGE_POOL
 	select PHYLINK
 	select CRC32

drivers/net/ethernet/stmicro/stmmac/common.h

@@ -15,6 +15,7 @@
 #include <linux/netdevice.h>
 #include <linux/stmmac.h>
 #include <linux/phy.h>
+#include <linux/mdio-xpcs.h>
 #include <linux/module.h>
 #if IS_ENABLED(CONFIG_VLAN_8021Q)
 #define STMMAC_VLAN_TAG_USED
@@ -446,6 +447,8 @@ struct mac_device_info {
 	const struct stmmac_hwtimestamp *ptp;
 	const struct stmmac_tc_ops *tc;
 	const struct stmmac_mmc_ops *mmc;
+	const struct mdio_xpcs_ops *xpcs;
+	struct mdio_xpcs_args xpcs_args;
 	struct mii_regs mii;	/* MII register Addresses */
 	struct mac_link link;
 	void __iomem *pcsr;     /* vpointer to device CSRs */

drivers/net/ethernet/stmicro/stmmac/hwif.h

@@ -577,6 +577,18 @@ struct stmmac_mmc_ops {
 #define stmmac_mmc_read(__priv, __args...) \
 	stmmac_do_void_callback(__priv, mmc, read, __args)
 
+/* XPCS callbacks */
+#define stmmac_xpcs_validate(__priv, __args...) \
+	stmmac_do_callback(__priv, xpcs, validate, __args)
+#define stmmac_xpcs_config(__priv, __args...) \
+	stmmac_do_callback(__priv, xpcs, config, __args)
+#define stmmac_xpcs_get_state(__priv, __args...) \
+	stmmac_do_callback(__priv, xpcs, get_state, __args)
+#define stmmac_xpcs_link_up(__priv, __args...) \
+	stmmac_do_callback(__priv, xpcs, link_up, __args)
+#define stmmac_xpcs_probe(__priv, __args...) \
+	stmmac_do_callback(__priv, xpcs, probe, __args)
+
 struct stmmac_regs_off {
 	u32 ptp_off;
 	u32 mmc_off;

drivers/net/ethernet/stmicro/stmmac/stmmac_main.c

@@ -858,33 +858,65 @@ static void stmmac_validate(struct phylink_config *config,
 		phylink_set(mask, 1000baseT_Half);
 	}
 
-	bitmap_and(supported, supported, mac_supported,
-		   __ETHTOOL_LINK_MODE_MASK_NBITS);
-	bitmap_andnot(supported, supported, mask,
-		      __ETHTOOL_LINK_MODE_MASK_NBITS);
-	bitmap_and(state->advertising, state->advertising, mac_supported,
-		   __ETHTOOL_LINK_MODE_MASK_NBITS);
-	bitmap_andnot(state->advertising, state->advertising, mask,
-		      __ETHTOOL_LINK_MODE_MASK_NBITS);
+	linkmode_and(supported, supported, mac_supported);
+	linkmode_andnot(supported, supported, mask);
+
+	linkmode_and(state->advertising, state->advertising, mac_supported);
+	linkmode_andnot(state->advertising, state->advertising, mask);
+
+	/* If PCS is supported, check which modes it supports. */
+	stmmac_xpcs_validate(priv, &priv->hw->xpcs_args, supported, state);
 }
 
 static void stmmac_mac_pcs_get_state(struct phylink_config *config,
 				     struct phylink_link_state *state)
 {
+	struct stmmac_priv *priv = netdev_priv(to_net_dev(config->dev));
+
 	state->link = 0;
+	stmmac_xpcs_get_state(priv, &priv->hw->xpcs_args, state);
 }
 
 static void stmmac_mac_config(struct phylink_config *config, unsigned int mode,
 			      const struct phylink_link_state *state)
 {
 	struct stmmac_priv *priv = netdev_priv(to_net_dev(config->dev));
+
+	stmmac_xpcs_config(priv, &priv->hw->xpcs_args, state);
+}
+
+static void stmmac_mac_an_restart(struct phylink_config *config)
+{
+	/* Not Supported */
+}
+
+static void stmmac_mac_link_down(struct phylink_config *config,
+				 unsigned int mode, phy_interface_t interface)
+{
+	struct stmmac_priv *priv = netdev_priv(to_net_dev(config->dev));
+
+	stmmac_mac_set(priv, priv->ioaddr, false);
+	priv->eee_active = false;
+	stmmac_eee_init(priv);
+	stmmac_set_eee_pls(priv, priv->hw, false);
+}
+
+static void stmmac_mac_link_up(struct phylink_config *config,
+			       struct phy_device *phy,
+			       unsigned int mode, phy_interface_t interface,
+			       int speed, int duplex,
+			       bool tx_pause, bool rx_pause)
+{
+	struct stmmac_priv *priv = netdev_priv(to_net_dev(config->dev));
 	u32 ctrl;
 
+	stmmac_xpcs_link_up(priv, &priv->hw->xpcs_args, speed, interface);
+
 	ctrl = readl(priv->ioaddr + MAC_CTRL_REG);
 	ctrl &= ~priv->hw->link.speed_mask;
 
-	if (state->interface == PHY_INTERFACE_MODE_USXGMII) {
-		switch (state->speed) {
+	if (interface == PHY_INTERFACE_MODE_USXGMII) {
+		switch (speed) {
 		case SPEED_10000:
 			ctrl |= priv->hw->link.xgmii.speed10000;
 			break;
@@ -898,7 +930,7 @@ static void stmmac_mac_config(struct phylink_config *config, unsigned int mode,
 			return;
 		}
 	} else {
-		switch (state->speed) {
+		switch (speed) {
 		case SPEED_2500:
 			ctrl |= priv->hw->link.speed2500;
 			break;
@@ -916,46 +948,21 @@ static void stmmac_mac_config(struct phylink_config *config, unsigned int mode,
 		}
 	}
 
-	priv->speed = state->speed;
+	priv->speed = speed;
 
 	if (priv->plat->fix_mac_speed)
-		priv->plat->fix_mac_speed(priv->plat->bsp_priv, state->speed);
+		priv->plat->fix_mac_speed(priv->plat->bsp_priv, speed);
 
-	if (!state->duplex)
+	if (!duplex)
 		ctrl &= ~priv->hw->link.duplex;
 	else
 		ctrl |= priv->hw->link.duplex;
 
 	/* Flow Control operation */
-	if (state->pause)
-		stmmac_mac_flow_ctrl(priv, state->duplex);
+	if (tx_pause && rx_pause)
+		stmmac_mac_flow_ctrl(priv, duplex);
 
 	writel(ctrl, priv->ioaddr + MAC_CTRL_REG);
-}
-
-static void stmmac_mac_an_restart(struct phylink_config *config)
-{
-	/* Not Supported */
-}
-
-static void stmmac_mac_link_down(struct phylink_config *config,
-				 unsigned int mode, phy_interface_t interface)
-{
-	struct stmmac_priv *priv = netdev_priv(to_net_dev(config->dev));
-
-	stmmac_mac_set(priv, priv->ioaddr, false);
-	priv->eee_active = false;
-	stmmac_eee_init(priv);
-	stmmac_set_eee_pls(priv, priv->hw, false);
-}
-
-static void stmmac_mac_link_up(struct phylink_config *config,
-			       struct phy_device *phy,
-			       unsigned int mode, phy_interface_t interface,
-			       int speed, int duplex,
-			       bool tx_pause, bool rx_pause)
-{
-	struct stmmac_priv *priv = netdev_priv(to_net_dev(config->dev));
 
 	stmmac_mac_set(priv, priv->ioaddr, true);
 	if (phy && priv->dma_cap.eee) {
@@ -1045,6 +1052,10 @@ static int stmmac_phy_setup(struct stmmac_priv *priv)
 
 	priv->phylink_config.dev = &priv->dev->dev;
 	priv->phylink_config.type = PHYLINK_NETDEV;
+	priv->phylink_config.pcs_poll = true;
+
+	if (!fwnode)
+		fwnode = dev_fwnode(priv->device);
 
 	phylink = phylink_create(&priv->phylink_config, fwnode,
 				 mode, &stmmac_phylink_mac_ops);
@@ -2689,7 +2700,8 @@ static int stmmac_open(struct net_device *dev)
 	int ret;
 
 	if (priv->hw->pcs != STMMAC_PCS_TBI &&
-	    priv->hw->pcs != STMMAC_PCS_RTBI) {
+	    priv->hw->pcs != STMMAC_PCS_RTBI &&
+	    priv->hw->xpcs == NULL) {
 		ret = stmmac_init_phy(dev);
 		if (ret) {
 			netdev_err(priv->dev,

drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c

@@ -382,6 +382,14 @@ int stmmac_mdio_register(struct net_device *ndev)
 		max_addr = PHY_MAX_ADDR;
 	}
 
+	if (mdio_bus_data->has_xpcs) {
+		priv->hw->xpcs = mdio_xpcs_get_ops();
+		if (!priv->hw->xpcs) {
+			err = -ENODEV;
+			goto bus_register_fail;
+		}
+	}
+
 	if (mdio_bus_data->needs_reset)
 		new_bus->reset = &stmmac_mdio_reset;
 
@@ -433,6 +441,25 @@ int stmmac_mdio_register(struct net_device *ndev)
 		found = 1;
 	}
 
+	/* Try to probe the XPCS by scanning all addresses. */
+	if (priv->hw->xpcs) {
+		struct mdio_xpcs_args *xpcs = &priv->hw->xpcs_args;
+		int ret, mode = priv->plat->phy_interface;
+		max_addr = PHY_MAX_ADDR;
+
+		xpcs->bus = new_bus;
+
+		for (addr = 0; addr < max_addr; addr++) {
+			xpcs->addr = addr;
+
+			ret = stmmac_xpcs_probe(priv, xpcs, mode);
+			if (!ret) {
+				found = 1;
+				break;
+			}
+		}
+	}
+
 	if (!found && !mdio_node) {
 		dev_warn(dev, "No PHY found\n");
 		mdiobus_unregister(new_bus);

drivers/net/ethernet/stmicro/stmmac/stmmac_selftests.c

@@ -380,7 +380,7 @@ static int stmmac_test_phy_loopback(struct stmmac_priv *priv)
 	int ret;
 
 	if (!priv->dev->phydev)
-		return -EBUSY;
+		return -EOPNOTSUPP;
 
 	ret = phy_loopback(priv->dev->phydev, true);
 	if (ret)

drivers/net/phy/Kconfig

@@ -214,6 +214,12 @@ config MDIO_XGENE
 	  This module provides a driver for the MDIO busses found in the
 	  APM X-Gene SoC's.
 
+config MDIO_XPCS
+	tristate "Synopsys DesignWare XPCS controller"
+	help
+	  This module provides helper functions for Synopsys DesignWare XPCS
+	  controllers.
+
 endif
 endif
 

drivers/net/phy/Makefile

@@ -44,6 +44,7 @@ obj-$(CONFIG_MDIO_OCTEON)	+= mdio-octeon.o
 obj-$(CONFIG_MDIO_SUN4I)	+= mdio-sun4i.o
 obj-$(CONFIG_MDIO_THUNDER)	+= mdio-thunder.o
 obj-$(CONFIG_MDIO_XGENE)	+= mdio-xgene.o
+obj-$(CONFIG_MDIO_XPCS)		+= mdio-xpcs.o
 
 obj-$(CONFIG_NETWORK_PHY_TIMESTAMPING) += mii_timestamper.o
 

drivers/net/phy/phylink.c

@@ -312,11 +312,13 @@ static int phylink_parse_mode(struct phylink *pl, struct fwnode_handle *fwnode)
 			phylink_set(pl->supported, 1000baseT_Half);
 			phylink_set(pl->supported, 1000baseT_Full);
 			phylink_set(pl->supported, 1000baseX_Full);
+			phylink_set(pl->supported, 1000baseKX_Full);
 			phylink_set(pl->supported, 2500baseT_Full);
 			phylink_set(pl->supported, 2500baseX_Full);
 			phylink_set(pl->supported, 5000baseT_Full);
 			phylink_set(pl->supported, 10000baseT_Full);
 			phylink_set(pl->supported, 10000baseKR_Full);
+			phylink_set(pl->supported, 10000baseKX4_Full);
 			phylink_set(pl->supported, 10000baseCR_Full);
 			phylink_set(pl->supported, 10000baseSR_Full);
 			phylink_set(pl->supported, 10000baseLR_Full);
@@ -338,6 +340,9 @@ static int phylink_parse_mode(struct phylink *pl, struct fwnode_handle *fwnode)
 				    "failed to validate link configuration for in-band status\n");
 			return -EINVAL;
 		}
+
+		/* Check if MAC/PCS also supports Autoneg. */
+		pl->link_config.an_enabled = phylink_test(pl->supported, Autoneg);
 	}
 
 	return 0;

include/linux/mdio-xpcs.h

+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2020 Synopsys, Inc. and/or its affiliates.
+ * Synopsys DesignWare XPCS helpers
+ */
+
+#ifndef __LINUX_MDIO_XPCS_H
+#define __LINUX_MDIO_XPCS_H
+
+#include <linux/phy.h>
+#include <linux/phylink.h>
+
+struct mdio_xpcs_args {
+	__ETHTOOL_DECLARE_LINK_MODE_MASK(supported);
+	struct mii_bus *bus;
+	int addr;
+};
+
+struct mdio_xpcs_ops {
+	int (*validate)(struct mdio_xpcs_args *xpcs,
+			unsigned long *supported,
+			struct phylink_link_state *state);
+	int (*config)(struct mdio_xpcs_args *xpcs,
+		      const struct phylink_link_state *state);
+	int (*get_state)(struct mdio_xpcs_args *xpcs,
+			 struct phylink_link_state *state);
+	int (*link_up)(struct mdio_xpcs_args *xpcs, int speed,
+		       phy_interface_t interface);
+	int (*probe)(struct mdio_xpcs_args *xpcs, phy_interface_t interface);
+};
+
+#if IS_ENABLED(CONFIG_MDIO_XPCS)
+struct mdio_xpcs_ops *mdio_xpcs_get_ops(void);
+#else
+static inline struct mdio_xpcs_ops *mdio_xpcs_get_ops(void)
+{
+	return NULL;
+}
+#endif
+
+#endif /* __LINUX_MDIO_XPCS_H */

include/linux/stmmac.h

@@ -80,6 +80,7 @@
 
 struct stmmac_mdio_bus_data {
 	unsigned int phy_mask;
+	unsigned int has_xpcs;
 	int *irqs;
 	int probed_phy_irq;
 	bool needs_reset;