Merge branch 'pcs-xpcs-stmmac-add-1000BASE-X-AN-for-network-switch'

Ong Boon Leong says:

====================
pcs-xpcs, stmmac: add 1000BASE-X AN for network switch

Thanks for v4 review feedback in [1] and [2]. I have changed the v5
implementation as follow.

v5 changes:
1/5 - No change from v4.
2/5 - No change from v4.
3/5 - [Fix] make xpcs_modify_changed() static and use
      mdiodev_modify_changed() for cleaner code as suggested by
      Russell King.
4/5 - [Fix] Use fwnode_get_phy_mode() as recommended by Andrew Lunn.
5/5 - [Fix] Make fwnode = of_fwnode_handle(priv->plat->phylink_node)
      order after priv = netdev_priv(dev).

v4 changes:
1/5 - Squash v3:1/7 & 2/7 patches into v4:1/6 so that it passes build.
2/5 - [No change] same as v3:3/7
3/5 - [Fix] Fix issues identified by Russell in [1]
4/5 - [Fix] Drop v3:5/7 patch per input by Russell in [2] and make
            dwmac-intel clear the ovr_an_inband flag if fixed-link
            is used in ACPI _DSD.
5/5 - [No change] same as v3:7/7

For the steps to setup ACPI _DSD and checking, they are the same
as in [3]

Reference:
[1] https://patchwork.kernel.org/comment/24894239/
[2] https://patchwork.kernel.org/comment/24895330/
[3] https://patchwork.kernel.org/project/netdevbpf/cover/20220610033610.114084-1-boon.leong.ong@intel.com/
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/dsa/sja1105/sja1105_main.c

@@ -2330,7 +2330,7 @@ int sja1105_static_config_reload(struct sja1105_private *priv,
 		else
 			mode = MLO_AN_PHY;
 
-		rc = xpcs_do_config(xpcs, priv->phy_mode[i], mode);
+		rc = xpcs_do_config(xpcs, priv->phy_mode[i], mode, NULL);
 		if (rc < 0)
 			goto out;
 

drivers/net/ethernet/stmicro/stmmac/dwmac-intel.c

@@ -251,7 +251,6 @@ static void intel_speed_mode_2500(struct net_device *ndev, void *intel_data)
 		priv->plat->mdio_bus_data->xpcs_an_inband = false;
 	} else {
 		priv->plat->max_speed = 1000;
-		priv->plat->phy_interface = PHY_INTERFACE_MODE_SGMII;
 		priv->plat->mdio_bus_data->xpcs_an_inband = true;
 	}
 }
@@ -443,6 +442,7 @@ static void common_default_data(struct plat_stmmacenet_data *plat)
 static int intel_mgbe_common_data(struct pci_dev *pdev,
 				  struct plat_stmmacenet_data *plat)
 {
+	struct fwnode_handle *fwnode;
 	char clk_name[20];
 	int ret;
 	int i;
@@ -561,12 +561,42 @@ static int intel_mgbe_common_data(struct pci_dev *pdev,
 	/* Use the last Rx queue */
 	plat->vlan_fail_q = plat->rx_queues_to_use - 1;
 
+	/* For fixed-link setup, we allow phy-mode setting */
+	fwnode = dev_fwnode(&pdev->dev);
+	if (fwnode) {
+		int phy_mode;
+
+		/* "phy-mode" setting is optional. If it is set,
+		 *  we allow either sgmii or 1000base-x for now.
+		 */
+		phy_mode = fwnode_get_phy_mode(fwnode);
+		if (phy_mode >= 0) {
+			if (phy_mode == PHY_INTERFACE_MODE_SGMII ||
+			    phy_mode == PHY_INTERFACE_MODE_1000BASEX)
+				plat->phy_interface = phy_mode;
+			else
+				dev_warn(&pdev->dev, "Invalid phy-mode\n");
+		}
+	}
+
 	/* Intel mgbe SGMII interface uses pcs-xcps */
-	if (plat->phy_interface == PHY_INTERFACE_MODE_SGMII) {
+	if (plat->phy_interface == PHY_INTERFACE_MODE_SGMII ||
+	    plat->phy_interface == PHY_INTERFACE_MODE_1000BASEX) {
 		plat->mdio_bus_data->has_xpcs = true;
 		plat->mdio_bus_data->xpcs_an_inband = true;
 	}
 
+	/* For fixed-link setup, we clear xpcs_an_inband */
+	if (fwnode) {
+		struct fwnode_handle *fixed_node;
+
+		fixed_node = fwnode_get_named_child_node(fwnode, "fixed-link");
+		if (fixed_node)
+			plat->mdio_bus_data->xpcs_an_inband = false;
+
+		fwnode_handle_put(fixed_node);
+	}
+
 	/* Ensure mdio bus scan skips intel serdes and pcs-xpcs */
 	plat->mdio_bus_data->phy_mask = 1 << INTEL_MGBE_ADHOC_ADDR;
 	plat->mdio_bus_data->phy_mask |= 1 << INTEL_MGBE_XPCS_ADDR;

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

@@ -1128,18 +1128,20 @@ static void stmmac_check_pcs_mode(struct stmmac_priv *priv)
 static int stmmac_init_phy(struct net_device *dev)
 {
 	struct stmmac_priv *priv = netdev_priv(dev);
-	struct device_node *node;
+	struct fwnode_handle *fwnode;
 	int ret;
 
-	node = priv->plat->phylink_node;
+	fwnode = of_fwnode_handle(priv->plat->phylink_node);
+	if (!fwnode)
+		fwnode = dev_fwnode(priv->device);
 
-	if (node)
-		ret = phylink_of_phy_connect(priv->phylink, node, 0);
+	if (fwnode)
+		ret = phylink_fwnode_phy_connect(priv->phylink, fwnode, 0);
 
 	/* Some DT bindings do not set-up the PHY handle. Let's try to
 	 * manually parse it
 	 */
-	if (!node || ret) {
+	if (!fwnode || ret) {
 		int addr = priv->plat->phy_addr;
 		struct phy_device *phydev;
 

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

@@ -434,9 +434,11 @@ int stmmac_mdio_register(struct net_device *ndev)
 	int err = 0;
 	struct mii_bus *new_bus;
 	struct stmmac_priv *priv = netdev_priv(ndev);
+	struct fwnode_handle *fwnode = of_fwnode_handle(priv->plat->phylink_node);
 	struct stmmac_mdio_bus_data *mdio_bus_data = priv->plat->mdio_bus_data;
 	struct device_node *mdio_node = priv->plat->mdio_node;
 	struct device *dev = ndev->dev.parent;
+	struct fwnode_handle *fixed_node;
 	int addr, found, max_addr;
 
 	if (!mdio_bus_data)
@@ -490,6 +492,18 @@ int stmmac_mdio_register(struct net_device *ndev)
 	if (priv->plat->has_xgmac)
 		stmmac_xgmac2_mdio_read(new_bus, 0, MII_ADDR_C45);
 
+	/* If fixed-link is set, skip PHY scanning */
+	if (!fwnode)
+		fwnode = dev_fwnode(priv->device);
+
+	if (fwnode) {
+		fixed_node = fwnode_get_named_child_node(fwnode, "fixed-link");
+		if (fixed_node) {
+			fwnode_handle_put(fixed_node);
+			goto bus_register_done;
+		}
+	}
+
 	if (priv->plat->phy_node || mdio_node)
 		goto bus_register_done;
 

drivers/net/pcs/pcs-xpcs.c

@@ -77,6 +77,14 @@ static const int xpcs_sgmii_features[] = {
 	__ETHTOOL_LINK_MODE_MASK_NBITS,
 };
 
+static const int xpcs_1000basex_features[] = {
+	ETHTOOL_LINK_MODE_Pause_BIT,
+	ETHTOOL_LINK_MODE_Asym_Pause_BIT,
+	ETHTOOL_LINK_MODE_Autoneg_BIT,
+	ETHTOOL_LINK_MODE_1000baseX_Full_BIT,
+	__ETHTOOL_LINK_MODE_MASK_NBITS,
+};
+
 static const int xpcs_2500basex_features[] = {
 	ETHTOOL_LINK_MODE_Pause_BIT,
 	ETHTOOL_LINK_MODE_Asym_Pause_BIT,
@@ -102,6 +110,10 @@ static const phy_interface_t xpcs_sgmii_interfaces[] = {
 	PHY_INTERFACE_MODE_SGMII,
 };
 
+static const phy_interface_t xpcs_1000basex_interfaces[] = {
+	PHY_INTERFACE_MODE_1000BASEX,
+};
+
 static const phy_interface_t xpcs_2500basex_interfaces[] = {
 	PHY_INTERFACE_MODE_2500BASEX,
 	PHY_INTERFACE_MODE_MAX,
@@ -112,6 +124,7 @@ enum {
 	DW_XPCS_10GKR,
 	DW_XPCS_XLGMII,
 	DW_XPCS_SGMII,
+	DW_XPCS_1000BASEX,
 	DW_XPCS_2500BASEX,
 	DW_XPCS_INTERFACE_MAX,
 };
@@ -189,6 +202,14 @@ int xpcs_write(struct dw_xpcs *xpcs, int dev, u32 reg, u16 val)
 	return mdiobus_c45_write(bus, addr, dev, reg, val);
 }
 
+static int xpcs_modify_changed(struct dw_xpcs *xpcs, int dev, u32 reg,
+			       u16 mask, u16 set)
+{
+	u32 reg_addr = mdiobus_c45_addr(dev, reg);
+
+	return mdiodev_modify_changed(xpcs->mdiodev, reg_addr, mask, set);
+}
+
 static int xpcs_read_vendor(struct dw_xpcs *xpcs, int dev, u32 reg)
 {
 	return xpcs_read(xpcs, dev, DW_VENDOR | reg);
@@ -237,6 +258,7 @@ static int xpcs_soft_reset(struct dw_xpcs *xpcs,
 		break;
 	case DW_AN_C37_SGMII:
 	case DW_2500BASEX:
+	case DW_AN_C37_1000BASEX:
 		dev = MDIO_MMD_VEND2;
 		break;
 	default:
@@ -772,6 +794,68 @@ static int xpcs_config_aneg_c37_sgmii(struct dw_xpcs *xpcs, unsigned int mode)
 	return ret;
 }
 
+static int xpcs_config_aneg_c37_1000basex(struct dw_xpcs *xpcs, unsigned int mode,
+					  const unsigned long *advertising)
+{
+	phy_interface_t interface = PHY_INTERFACE_MODE_1000BASEX;
+	int ret, mdio_ctrl, adv;
+	bool changed = 0;
+
+	/* According to Chap 7.12, to set 1000BASE-X C37 AN, AN must
+	 * be disabled first:-
+	 * 1) VR_MII_MMD_CTRL Bit(12)[AN_ENABLE] = 0b
+	 * 2) VR_MII_AN_CTRL Bit(2:1)[PCS_MODE] = 00b (1000BASE-X C37)
+	 */
+	mdio_ctrl = xpcs_read(xpcs, MDIO_MMD_VEND2, DW_VR_MII_MMD_CTRL);
+	if (mdio_ctrl < 0)
+		return mdio_ctrl;
+
+	if (mdio_ctrl & AN_CL37_EN) {
+		ret = xpcs_write(xpcs, MDIO_MMD_VEND2, DW_VR_MII_MMD_CTRL,
+				 mdio_ctrl & ~AN_CL37_EN);
+		if (ret < 0)
+			return ret;
+	}
+
+	ret = xpcs_read(xpcs, MDIO_MMD_VEND2, DW_VR_MII_AN_CTRL);
+	if (ret < 0)
+		return ret;
+
+	ret &= ~DW_VR_MII_PCS_MODE_MASK;
+	ret = xpcs_write(xpcs, MDIO_MMD_VEND2, DW_VR_MII_AN_CTRL, ret);
+	if (ret < 0)
+		return ret;
+
+	/* Check for advertising changes and update the C45 MII ADV
+	 * register accordingly.
+	 */
+	adv = phylink_mii_c22_pcs_encode_advertisement(interface,
+						       advertising);
+	if (adv >= 0) {
+		ret = xpcs_modify_changed(xpcs, MDIO_MMD_VEND2,
+					  MII_ADVERTISE, 0xffff, adv);
+		if (ret < 0)
+			return ret;
+
+		changed = ret;
+	}
+
+	/* Clear CL37 AN complete status */
+	ret = xpcs_write(xpcs, MDIO_MMD_VEND2, DW_VR_MII_AN_INTR_STS, 0);
+	if (ret < 0)
+		return ret;
+
+	if (phylink_autoneg_inband(mode) &&
+	    linkmode_test_bit(ETHTOOL_LINK_MODE_Autoneg_BIT, advertising)) {
+		ret = xpcs_write(xpcs, MDIO_MMD_VEND2, DW_VR_MII_MMD_CTRL,
+				 mdio_ctrl | AN_CL37_EN);
+		if (ret < 0)
+			return ret;
+	}
+
+	return changed;
+}
+
 static int xpcs_config_2500basex(struct dw_xpcs *xpcs)
 {
 	int ret;
@@ -795,7 +879,7 @@ static int xpcs_config_2500basex(struct dw_xpcs *xpcs)
 }
 
 int xpcs_do_config(struct dw_xpcs *xpcs, phy_interface_t interface,
-		   unsigned int mode)
+		   unsigned int mode, const unsigned long *advertising)
 {
 	const struct xpcs_compat *compat;
 	int ret;
@@ -817,6 +901,12 @@ int xpcs_do_config(struct dw_xpcs *xpcs, phy_interface_t interface,
 		if (ret)
 			return ret;
 		break;
+	case DW_AN_C37_1000BASEX:
+		ret = xpcs_config_aneg_c37_1000basex(xpcs, mode,
+						     advertising);
+		if (ret)
+			return ret;
+		break;
 	case DW_2500BASEX:
 		ret = xpcs_config_2500basex(xpcs);
 		if (ret)
@@ -843,7 +933,7 @@ static int xpcs_config(struct phylink_pcs *pcs, unsigned int mode,
 {
 	struct dw_xpcs *xpcs = phylink_pcs_to_xpcs(pcs);
 
-	return xpcs_do_config(xpcs, interface, mode);
+	return xpcs_do_config(xpcs, interface, mode, advertising);
 }
 
 static int xpcs_get_state_c73(struct dw_xpcs *xpcs,
@@ -864,7 +954,7 @@ static int xpcs_get_state_c73(struct dw_xpcs *xpcs,
 
 		state->link = 0;
 
-		return xpcs_do_config(xpcs, state->interface, MLO_AN_INBAND);
+		return xpcs_do_config(xpcs, state->interface, MLO_AN_INBAND, NULL);
 	}
 
 	if (state->an_enabled && xpcs_aneg_done_c73(xpcs, state, compat)) {
@@ -921,6 +1011,29 @@ static int xpcs_get_state_c37_sgmii(struct dw_xpcs *xpcs,
 	return 0;
 }
 
+static int xpcs_get_state_c37_1000basex(struct dw_xpcs *xpcs,
+					struct phylink_link_state *state)
+{
+	int lpa, bmsr;
+
+	if (state->an_enabled) {
+		/* Reset link state */
+		state->link = false;
+
+		lpa = xpcs_read(xpcs, MDIO_MMD_VEND2, MII_LPA);
+		if (lpa < 0 || lpa & LPA_RFAULT)
+			return lpa;
+
+		bmsr = xpcs_read(xpcs, MDIO_MMD_VEND2, MII_BMSR);
+		if (bmsr < 0)
+			return bmsr;
+
+		phylink_mii_c22_pcs_decode_state(state, bmsr, lpa);
+	}
+
+	return 0;
+}
+
 static void xpcs_get_state(struct phylink_pcs *pcs,
 			   struct phylink_link_state *state)
 {
@@ -948,6 +1061,13 @@ static void xpcs_get_state(struct phylink_pcs *pcs,
 			       ERR_PTR(ret));
 		}
 		break;
+	case DW_AN_C37_1000BASEX:
+		ret = xpcs_get_state_c37_1000basex(xpcs, state);
+		if (ret) {
+			pr_err("xpcs_get_state_c37_1000basex returned %pe\n",
+			       ERR_PTR(ret));
+		}
+		break;
 	default:
 		return;
 	}
@@ -983,6 +1103,35 @@ static void xpcs_link_up_sgmii(struct dw_xpcs *xpcs, unsigned int mode,
 		pr_err("%s: xpcs_write returned %pe\n", __func__, ERR_PTR(ret));
 }
 
+static void xpcs_link_up_1000basex(struct dw_xpcs *xpcs, unsigned int mode,
+				   int speed, int duplex)
+{
+	int val, ret;
+
+	if (phylink_autoneg_inband(mode))
+		return;
+
+	switch (speed) {
+	case SPEED_1000:
+		val = BMCR_SPEED1000;
+		break;
+	case SPEED_100:
+	case SPEED_10:
+	default:
+		pr_err("%s: speed = %d\n", __func__, speed);
+		return;
+	}
+
+	if (duplex == DUPLEX_FULL)
+		val |= BMCR_FULLDPLX;
+	else
+		pr_err("%s: half duplex not supported\n", __func__);
+
+	ret = xpcs_write(xpcs, MDIO_MMD_VEND2, MDIO_CTRL1, val);
+	if (ret)
+		pr_err("%s: xpcs_write returned %pe\n", __func__, ERR_PTR(ret));
+}
+
 void xpcs_link_up(struct phylink_pcs *pcs, unsigned int mode,
 		  phy_interface_t interface, int speed, int duplex)
 {
@@ -992,9 +1141,23 @@ void xpcs_link_up(struct phylink_pcs *pcs, unsigned int mode,
 		return xpcs_config_usxgmii(xpcs, speed);
 	if (interface == PHY_INTERFACE_MODE_SGMII)
 		return xpcs_link_up_sgmii(xpcs, mode, speed, duplex);
+	if (interface == PHY_INTERFACE_MODE_1000BASEX)
+		return xpcs_link_up_1000basex(xpcs, mode, speed, duplex);
 }
 EXPORT_SYMBOL_GPL(xpcs_link_up);
 
+static void xpcs_an_restart(struct phylink_pcs *pcs)
+{
+	struct dw_xpcs *xpcs = phylink_pcs_to_xpcs(pcs);
+	int ret;
+
+	ret = xpcs_read(xpcs, MDIO_MMD_VEND2, MDIO_CTRL1);
+	if (ret >= 0) {
+		ret |= BMCR_ANRESTART;
+		xpcs_write(xpcs, MDIO_MMD_VEND2, MDIO_CTRL1, ret);
+	}
+}
+
 static u32 xpcs_get_id(struct dw_xpcs *xpcs)
 {
 	int ret;
@@ -1060,6 +1223,12 @@ static const struct xpcs_compat synopsys_xpcs_compat[DW_XPCS_INTERFACE_MAX] = {
 		.num_interfaces = ARRAY_SIZE(xpcs_sgmii_interfaces),
 		.an_mode = DW_AN_C37_SGMII,
 	},
+	[DW_XPCS_1000BASEX] = {
+		.supported = xpcs_1000basex_features,
+		.interface = xpcs_1000basex_interfaces,
+		.num_interfaces = ARRAY_SIZE(xpcs_1000basex_interfaces),
+		.an_mode = DW_AN_C37_1000BASEX,
+	},
 	[DW_XPCS_2500BASEX] = {
 		.supported = xpcs_2500basex_features,
 		.interface = xpcs_2500basex_interfaces,
@@ -1115,6 +1284,7 @@ static const struct phylink_pcs_ops xpcs_phylink_ops = {
 	.pcs_validate = xpcs_validate,
 	.pcs_config = xpcs_config,
 	.pcs_get_state = xpcs_get_state,
+	.pcs_an_restart = xpcs_an_restart,
 	.pcs_link_up = xpcs_link_up,
 };
 

drivers/net/pcs/pcs-xpcs.h

@@ -109,7 +109,6 @@
 
 int xpcs_read(struct dw_xpcs *xpcs, int dev, u32 reg);
 int xpcs_write(struct dw_xpcs *xpcs, int dev, u32 reg, u16 val);
-
 int nxp_sja1105_sgmii_pma_config(struct dw_xpcs *xpcs);
 int nxp_sja1110_sgmii_pma_config(struct dw_xpcs *xpcs);
 int nxp_sja1110_2500basex_pma_config(struct dw_xpcs *xpcs);

include/linux/pcs/pcs-xpcs.h

@@ -17,6 +17,7 @@
 #define DW_AN_C73			1
 #define DW_AN_C37_SGMII			2
 #define DW_2500BASEX			3
+#define DW_AN_C37_1000BASEX		4
 
 struct xpcs_id;
 
@@ -30,7 +31,7 @@ int xpcs_get_an_mode(struct dw_xpcs *xpcs, phy_interface_t interface);
 void xpcs_link_up(struct phylink_pcs *pcs, unsigned int mode,
 		  phy_interface_t interface, int speed, int duplex);
 int xpcs_do_config(struct dw_xpcs *xpcs, phy_interface_t interface,
-		   unsigned int mode);
+		   unsigned int mode, const unsigned long *advertising);
 void xpcs_get_interfaces(struct dw_xpcs *xpcs, unsigned long *interfaces);
 int xpcs_config_eee(struct dw_xpcs *xpcs, int mult_fact_100ns,
 		    int enable);