diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-intel.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-intel.c
index 2ecf93c84b9d..6a9a19b0844c 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac-intel.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-intel.c
@@ -102,6 +102,22 @@ static int intel_serdes_powerup(struct net_device *ndev, void *priv_data)
 
 	serdes_phy_addr = intel_priv->mdio_adhoc_addr;
 
+	/* Set the serdes rate and the PCLK rate */
+	data = mdiobus_read(priv->mii, serdes_phy_addr,
+			    SERDES_GCR0);
+
+	data &= ~SERDES_RATE_MASK;
+	data &= ~SERDES_PCLK_MASK;
+
+	if (priv->plat->max_speed == 2500)
+		data |= SERDES_RATE_PCIE_GEN2 << SERDES_RATE_PCIE_SHIFT |
+			SERDES_PCLK_37p5MHZ << SERDES_PCLK_SHIFT;
+	else
+		data |= SERDES_RATE_PCIE_GEN1 << SERDES_RATE_PCIE_SHIFT |
+			SERDES_PCLK_70MHZ << SERDES_PCLK_SHIFT;
+
+	mdiobus_write(priv->mii, serdes_phy_addr, SERDES_GCR0, data);
+
 	/* assert clk_req */
 	data = mdiobus_read(priv->mii, serdes_phy_addr, SERDES_GCR0);
 	data |= SERDES_PLL_CLK;
@@ -230,6 +246,32 @@ static void intel_serdes_powerdown(struct net_device *ndev, void *intel_data)
 	}
 }
 
+static void intel_speed_mode_2500(struct net_device *ndev, void *intel_data)
+{
+	struct intel_priv_data *intel_priv = intel_data;
+	struct stmmac_priv *priv = netdev_priv(ndev);
+	int serdes_phy_addr = 0;
+	u32 data = 0;
+
+	serdes_phy_addr = intel_priv->mdio_adhoc_addr;
+
+	/* Determine the link speed mode: 2.5Gbps/1Gbps */
+	data = mdiobus_read(priv->mii, serdes_phy_addr,
+			    SERDES_GCR);
+
+	if (((data & SERDES_LINK_MODE_MASK) >> SERDES_LINK_MODE_SHIFT) ==
+	    SERDES_LINK_MODE_2G5) {
+		dev_info(priv->device, "Link Speed Mode: 2.5Gbps\n");
+		priv->plat->max_speed = 2500;
+		priv->plat->phy_interface = PHY_INTERFACE_MODE_2500BASEX;
+		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;
+	}
+}
+
 /* Program PTP Clock Frequency for different variant of
  * Intel mGBE that has slightly different GPO mapping
  */
@@ -586,7 +628,7 @@ static int ehl_sgmii_data(struct pci_dev *pdev,
 {
 	plat->bus_id = 1;
 	plat->phy_interface = PHY_INTERFACE_MODE_SGMII;
-
+	plat->speed_mode_2500 = intel_speed_mode_2500;
 	plat->serdes_powerup = intel_serdes_powerup;
 	plat->serdes_powerdown = intel_serdes_powerdown;
 
@@ -639,6 +681,7 @@ static int ehl_pse0_sgmii1g_data(struct pci_dev *pdev,
 				 struct plat_stmmacenet_data *plat)
 {
 	plat->phy_interface = PHY_INTERFACE_MODE_SGMII;
+	plat->speed_mode_2500 = intel_speed_mode_2500;
 	plat->serdes_powerup = intel_serdes_powerup;
 	plat->serdes_powerdown = intel_serdes_powerdown;
 	return ehl_pse0_common_data(pdev, plat);
@@ -677,6 +720,7 @@ static int ehl_pse1_sgmii1g_data(struct pci_dev *pdev,
 				 struct plat_stmmacenet_data *plat)
 {
 	plat->phy_interface = PHY_INTERFACE_MODE_SGMII;
+	plat->speed_mode_2500 = intel_speed_mode_2500;
 	plat->serdes_powerup = intel_serdes_powerup;
 	plat->serdes_powerdown = intel_serdes_powerdown;
 	return ehl_pse1_common_data(pdev, plat);
@@ -711,6 +755,7 @@ static int tgl_sgmii_phy0_data(struct pci_dev *pdev,
 {
 	plat->bus_id = 1;
 	plat->phy_interface = PHY_INTERFACE_MODE_SGMII;
+	plat->speed_mode_2500 = intel_speed_mode_2500;
 	plat->serdes_powerup = intel_serdes_powerup;
 	plat->serdes_powerdown = intel_serdes_powerdown;
 	return tgl_common_data(pdev, plat);
@@ -725,6 +770,7 @@ static int tgl_sgmii_phy1_data(struct pci_dev *pdev,
 {
 	plat->bus_id = 2;
 	plat->phy_interface = PHY_INTERFACE_MODE_SGMII;
+	plat->speed_mode_2500 = intel_speed_mode_2500;
 	plat->serdes_powerup = intel_serdes_powerup;
 	plat->serdes_powerdown = intel_serdes_powerdown;
 	return tgl_common_data(pdev, plat);
diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-intel.h b/drivers/net/ethernet/stmicro/stmmac/dwmac-intel.h
index 542acb8ce467..20d14e588044 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac-intel.h
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-intel.h
@@ -9,6 +9,7 @@
 #define POLL_DELAY_US 8
 
 /* SERDES Register */
+#define SERDES_GCR	0x0	/* Global Conguration */
 #define SERDES_GSR0	0x5	/* Global Status Reg0 */
 #define SERDES_GCR0	0xb	/* Global Configuration Reg0 */
 
@@ -17,8 +18,20 @@
 #define SERDES_PHY_RX_CLK	BIT(1)		/* PSE SGMII PHY rx clk */
 #define SERDES_RST		BIT(2)		/* Serdes Reset */
 #define SERDES_PWR_ST_MASK	GENMASK(6, 4)	/* Serdes Power state*/
+#define SERDES_RATE_MASK	GENMASK(9, 8)
+#define SERDES_PCLK_MASK	GENMASK(14, 12)	/* PCLK rate to PHY */
+#define SERDES_LINK_MODE_MASK	GENMASK(2, 1)
+#define SERDES_LINK_MODE_SHIFT	1
 #define SERDES_PWR_ST_SHIFT	4
 #define SERDES_PWR_ST_P0	0x0
 #define SERDES_PWR_ST_P3	0x3
+#define SERDES_LINK_MODE_2G5	0x3
+#define SERSED_LINK_MODE_1G	0x2
+#define SERDES_PCLK_37p5MHZ	0x0
+#define SERDES_PCLK_70MHZ	0x1
+#define SERDES_RATE_PCIE_GEN1	0x0
+#define SERDES_RATE_PCIE_GEN2	0x1
+#define SERDES_RATE_PCIE_SHIFT	8
+#define SERDES_PCLK_SHIFT	12
 
 #endif /* __DWMAC_INTEL_H__ */
diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c b/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c
index f35c03c9f91e..67ba083eb90c 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c
@@ -1358,6 +1358,7 @@ int dwmac4_setup(struct stmmac_priv *priv)
 	mac->link.speed10 = GMAC_CONFIG_PS;
 	mac->link.speed100 = GMAC_CONFIG_FES | GMAC_CONFIG_PS;
 	mac->link.speed1000 = 0;
+	mac->link.speed2500 = GMAC_CONFIG_FES;
 	mac->link.speed_mask = GMAC_CONFIG_FES | GMAC_CONFIG_PS;
 	mac->mii.addr = GMAC_MDIO_ADDR;
 	mac->mii.data = GMAC_MDIO_DATA;
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index af406ea3dd46..1b12a2f8bfb5 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -931,6 +931,10 @@ static void stmmac_validate(struct phylink_config *config,
 	if ((max_speed > 0) && (max_speed < 1000)) {
 		phylink_set(mask, 1000baseT_Full);
 		phylink_set(mask, 1000baseX_Full);
+	} else if (priv->plat->has_gmac4) {
+		if (!max_speed || max_speed >= 2500)
+			phylink_set(mac_supported, 2500baseT_Full);
+			phylink_set(mac_supported, 2500baseX_Full);
 	} else if (priv->plat->has_xgmac) {
 		if (!max_speed || (max_speed >= 2500)) {
 			phylink_set(mac_supported, 2500baseT_Full);
@@ -6993,6 +6997,9 @@ int stmmac_dvr_probe(struct device *device,
 		}
 	}
 
+	if (priv->plat->speed_mode_2500)
+		priv->plat->speed_mode_2500(ndev, priv->plat->bsp_priv);
+
 	if (priv->plat->mdio_bus_data) {
 		if (priv->plat->mdio_bus_data->has_xpcs) {
 			ret = stmmac_xpcs_setup(priv->mii);
diff --git a/include/linux/stmmac.h b/include/linux/stmmac.h
index e55a4807e3ea..b10be3385a30 100644
--- a/include/linux/stmmac.h
+++ b/include/linux/stmmac.h
@@ -223,6 +223,7 @@ struct plat_stmmacenet_data {
 	void (*fix_mac_speed)(void *priv, unsigned int speed);
 	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);
 	void (*ptp_clk_freq_config)(void *priv);
 	int (*init)(struct platform_device *pdev, void *priv);
 	void (*exit)(struct platform_device *pdev, void *priv);