[PATCH net-next v4 05/11] net: stmmac: select PCS negotiation mode according to the interface mode

[Choong Yong Liang <yong.liang.choong@xxxxxxxxxxxxxxx>]

The 'stmmac_get_pcs_neg_mode' is invoked during link initialization or
interface mode changes.

In cases where 'priv->plat->get_pcs_neg_mode' is absent, the default
'phylink_pcs_neg_mode' function is utilized.

Additionally, the 'intel_get_pcs_neg_mode' function is available to
determine the PCS negotiation mode based on the provided interface mode.

Signed-off-by: Choong Yong Liang <yong.liang.choong@xxxxxxxxxxxxxxx>
---
 .../net/ethernet/stmicro/stmmac/dwmac-intel.c | 44 +++++++++++++++----
 .../net/ethernet/stmicro/stmmac/stmmac_main.c | 17 +++++++
 include/linux/stmmac.h                        |  2 +
 3 files changed, 54 insertions(+), 9 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-intel.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-intel.c
index 60283543ffc8..5110af776c8f 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac-intel.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-intel.c
@@ -414,6 +414,39 @@ static void intel_mgbe_pse_crossts_adj(struct intel_priv_data *intel_priv,
 	}
 }
 
+static bool is_fixed_link(struct pci_dev *pdev)
+{
+	struct fwnode_handle *fwnode = dev_fwnode(&pdev->dev);
+	bool is_fixed_link = false;
+
+	if (fwnode) {
+		struct fwnode_handle *fixed_node;
+
+		fixed_node = fwnode_get_named_child_node(fwnode, "fixed-link");
+		if (fixed_node)
+			is_fixed_link = true;
+
+		fwnode_handle_put(fixed_node);
+	}
+
+	return is_fixed_link;
+}
+
+static unsigned int intel_get_pcs_neg_mode(phy_interface_t interface,
+					   struct pci_dev *pdev)
+{
+	unsigned int neg_mode;
+
+	if ((interface == PHY_INTERFACE_MODE_SGMII ||
+	     interface == PHY_INTERFACE_MODE_1000BASEX) &&
+	     !is_fixed_link(pdev))
+		neg_mode = PHYLINK_PCS_NEG_INBAND_ENABLED;
+	else
+		neg_mode = PHYLINK_PCS_NEG_OUTBAND;
+
+	return neg_mode;
+}
+
 static void common_default_data(struct plat_stmmacenet_data *plat)
 {
 	plat->clk_csr = 2;	/* clk_csr_i = 20-35MHz & MDC = clk_csr_i/16 */
@@ -590,15 +623,8 @@ static int intel_mgbe_common_data(struct pci_dev *pdev,
 	}
 
 	/* 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);
-	}
+	if (is_fixed_link(pdev))
+		plat->mdio_bus_data->xpcs_an_inband = false;
 
 	/* Ensure mdio bus scan skips intel serdes and pcs-xpcs */
 	plat->mdio_bus_data->phy_mask = 1 << INTEL_MGBE_ADHOC_ADDR;
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index d1ec075ae10a..00af5a4195fd 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -1104,11 +1104,28 @@ static void stmmac_mac_link_up(struct phylink_config *config,
 		stmmac_hwtstamp_correct_latency(priv, priv);
 }
 
+static unsigned int stmmac_get_pcs_neg_mode(struct phylink_config *config,
+					    unsigned int mode,
+					    phy_interface_t interface,
+					    const unsigned long *advertising)
+{
+	struct stmmac_priv *priv = netdev_priv(to_net_dev(config->dev));
+	unsigned int neg_mode;
+
+	if (priv->plat->get_pcs_neg_mode)
+		neg_mode = priv->plat->get_pcs_neg_mode(interface, priv->plat->pdev);
+	else
+		neg_mode = phylink_pcs_neg_mode(mode, interface, advertising);
+
+	return neg_mode;
+}
+
 static const struct phylink_mac_ops stmmac_phylink_mac_ops = {
 	.mac_select_pcs = stmmac_mac_select_pcs,
 	.mac_config = stmmac_mac_config,
 	.mac_link_down = stmmac_mac_link_down,
 	.mac_link_up = stmmac_mac_link_up,
+	.mac_get_pcs_neg_mode = stmmac_get_pcs_neg_mode,
 };
 
 /**
diff --git a/include/linux/stmmac.h b/include/linux/stmmac.h
index b99d11f4ff26..778bdfc3f010 100644
--- a/include/linux/stmmac.h
+++ b/include/linux/stmmac.h
@@ -277,6 +277,8 @@ struct plat_stmmacenet_data {
 	int (*serdes_powerup)(struct net_device *ndev, void *priv);
 	void (*serdes_powerdown)(struct net_device *ndev, void *priv);
 	void (*speed_mode_2500)(struct net_device *ndev, void *priv);
+	unsigned int (*get_pcs_neg_mode)(phy_interface_t interface,
+					 struct pci_dev *pdev);
 	void (*ptp_clk_freq_config)(struct stmmac_priv *priv);
 	int (*init)(struct platform_device *pdev, void *priv);
 	void (*exit)(struct platform_device *pdev, void *priv);
-- 
2.34.1