diff --git a/drivers/net/dsa/realtek/rtl8365mb.c b/drivers/net/dsa/realtek/rtl8365mb.c
index b411b620fec1..8bffdcb99a3d 100644
--- a/drivers/net/dsa/realtek/rtl8365mb.c
+++ b/drivers/net/dsa/realtek/rtl8365mb.c
@@ -105,6 +105,7 @@
 #define RTL8365MB_CHIP_ID_8365MB_VC		0x6367
 #define RTL8365MB_CPU_PORT_NUM_8365MB_VC	6
 #define RTL8365MB_LEARN_LIMIT_MAX_8365MB_VC	2112
+static const int rtl8365mb_extint_port_map[] = { -1, -1, -1, -1, -1, -1, 1 };
 
 /* Family-specific data and limits */
 #define RTL8365MB_PHYADDRMAX	7
@@ -191,7 +192,7 @@
 /* The PHY OCP addresses of PHY registers 0~31 start here */
 #define RTL8365MB_PHY_OCP_ADDR_PHYREG_BASE		0xA400
 
-/* EXT port interface mode values - used in DIGITAL_INTERFACE_SELECT */
+/* EXT interface port mode values - used in DIGITAL_INTERFACE_SELECT */
 #define RTL8365MB_EXT_PORT_MODE_DISABLE		0
 #define RTL8365MB_EXT_PORT_MODE_RGMII		1
 #define RTL8365MB_EXT_PORT_MODE_MII_MAC		2
@@ -207,39 +208,56 @@
 #define RTL8365MB_EXT_PORT_MODE_1000X		12
 #define RTL8365MB_EXT_PORT_MODE_100FX		13
 
-/* EXT port interface mode configuration registers 0~1 */
-#define RTL8365MB_DIGITAL_INTERFACE_SELECT_REG0		0x1305
-#define RTL8365MB_DIGITAL_INTERFACE_SELECT_REG1		0x13C3
-#define RTL8365MB_DIGITAL_INTERFACE_SELECT_REG(_extport)   \
-		(RTL8365MB_DIGITAL_INTERFACE_SELECT_REG0 + \
-		 ((_extport) >> 1) * (0x13C3 - 0x1305))
-#define   RTL8365MB_DIGITAL_INTERFACE_SELECT_MODE_MASK(_extport) \
-		(0xF << (((_extport) % 2)))
-#define   RTL8365MB_DIGITAL_INTERFACE_SELECT_MODE_OFFSET(_extport) \
-		(((_extport) % 2) * 4)
-
-/* EXT port RGMII TX/RX delay configuration registers 1~2 */
-#define RTL8365MB_EXT_RGMXF_REG1		0x1307
-#define RTL8365MB_EXT_RGMXF_REG2		0x13C5
-#define RTL8365MB_EXT_RGMXF_REG(_extport)   \
-		(RTL8365MB_EXT_RGMXF_REG1 + \
-		 (((_extport) >> 1) * (0x13C5 - 0x1307)))
+/* Realtek docs and driver uses logic number as EXT_PORT0=16, EXT_PORT1=17,
+ * EXT_PORT2=18, to interact with switch ports. That logic number is internally
+ * converted to either a physical port number (0..9) or an external interface id (0..2),
+ * depending on which function was called. The external interface id is calculated as
+ * (ext_id=logic_port-15), while the logical to physical map depends on the chip id/version.
+ *
+ * EXT_PORT0 mentioned in datasheets and rtl8367c driver is used in this driver
+ * as extid==1, EXT_PORT2, mentioned in Realtek rtl8367c driver for 10-port switches,
+ * would have an ext_id of 3 (out of range for most extint macros) and ext_id 0 does
+ * not seem to be used as well for this family.
+ */
+
+/* EXT interface mode configuration registers 0~1 */
+#define RTL8365MB_DIGITAL_INTERFACE_SELECT_REG0		0x1305 /* EXT1 */
+#define RTL8365MB_DIGITAL_INTERFACE_SELECT_REG1		0x13C3 /* EXT2 */
+#define RTL8365MB_DIGITAL_INTERFACE_SELECT_REG(_extint) \
+		((_extint) == 1 ? RTL8365MB_DIGITAL_INTERFACE_SELECT_REG0 : \
+		 (_extint) == 2 ? RTL8365MB_DIGITAL_INTERFACE_SELECT_REG1 : \
+		 0x0)
+#define   RTL8365MB_DIGITAL_INTERFACE_SELECT_MODE_MASK(_extint) \
+		(0xF << (((_extint) % 2)))
+#define   RTL8365MB_DIGITAL_INTERFACE_SELECT_MODE_OFFSET(_extint) \
+		(((_extint) % 2) * 4)
+
+/* EXT interface RGMII TX/RX delay configuration registers 0~2 */
+#define RTL8365MB_EXT_RGMXF_REG0		0x1306 /* EXT0 */
+#define RTL8365MB_EXT_RGMXF_REG1		0x1307 /* EXT1 */
+#define RTL8365MB_EXT_RGMXF_REG2		0x13C5 /* EXT2 */
+#define RTL8365MB_EXT_RGMXF_REG(_extint) \
+		((_extint) == 0 ? RTL8365MB_EXT_RGMXF_REG0 : \
+		 (_extint) == 1 ? RTL8365MB_EXT_RGMXF_REG1 : \
+		 (_extint) == 2 ? RTL8365MB_EXT_RGMXF_REG2 : \
+		 0x0)
 #define   RTL8365MB_EXT_RGMXF_RXDELAY_MASK	0x0007
 #define   RTL8365MB_EXT_RGMXF_TXDELAY_MASK	0x0008
 
-/* External port speed values - used in DIGITAL_INTERFACE_FORCE */
+/* External interface port speed values - used in DIGITAL_INTERFACE_FORCE */
 #define RTL8365MB_PORT_SPEED_10M	0
 #define RTL8365MB_PORT_SPEED_100M	1
 #define RTL8365MB_PORT_SPEED_1000M	2
 
-/* EXT port force configuration registers 0~2 */
-#define RTL8365MB_DIGITAL_INTERFACE_FORCE_REG0			0x1310
-#define RTL8365MB_DIGITAL_INTERFACE_FORCE_REG1			0x1311
-#define RTL8365MB_DIGITAL_INTERFACE_FORCE_REG2			0x13C4
-#define RTL8365MB_DIGITAL_INTERFACE_FORCE_REG(_extport)   \
-		(RTL8365MB_DIGITAL_INTERFACE_FORCE_REG0 + \
-		 ((_extport) & 0x1) +                     \
-		 ((((_extport) >> 1) & 0x1) * (0x13C4 - 0x1310)))
+/* EXT interface force configuration registers 0~2 */
+#define RTL8365MB_DIGITAL_INTERFACE_FORCE_REG0		0x1310 /* EXT0 */
+#define RTL8365MB_DIGITAL_INTERFACE_FORCE_REG1		0x1311 /* EXT1 */
+#define RTL8365MB_DIGITAL_INTERFACE_FORCE_REG2		0x13C4 /* EXT2 */
+#define RTL8365MB_DIGITAL_INTERFACE_FORCE_REG(_extint) \
+		((_extint) == 0 ? RTL8365MB_DIGITAL_INTERFACE_FORCE_REG0 : \
+		 (_extint) == 1 ? RTL8365MB_DIGITAL_INTERFACE_FORCE_REG1 : \
+		 (_extint) == 2 ? RTL8365MB_DIGITAL_INTERFACE_FORCE_REG2 : \
+		 0x0)
 #define   RTL8365MB_DIGITAL_INTERFACE_FORCE_EN_MASK		0x1000
 #define   RTL8365MB_DIGITAL_INTERFACE_FORCE_NWAY_MASK		0x0080
 #define   RTL8365MB_DIGITAL_INTERFACE_FORCE_TXPAUSE_MASK	0x0040
@@ -755,20 +773,25 @@ static int rtl8365mb_ext_config_rgmii(struct realtek_priv *priv, int port,
 	struct dsa_port *dp;
 	int tx_delay = 0;
 	int rx_delay = 0;
-	int ext_port;
+	int ext_int;
 	u32 val;
 	int ret;
 
-	if (port == priv->cpu_port) {
-		ext_port = 1;
-	} else {
-		dev_err(priv->dev, "only one EXT port is currently supported\n");
+	if (port != priv->cpu_port) {
+		dev_err(priv->dev, "only one EXT interface is currently supported\n");
 		return -EINVAL;
 	}
 
 	dp = dsa_to_port(priv->ds, port);
 	dn = dp->dn;
 
+	ext_int = rtl8365mb_extint_port_map[port];
+
+	if (ext_int <= 0) {
+		dev_err(priv->dev, "Port %d is not an external interface port\n", port);
+		return -EINVAL;
+	}
+
 	/* Set the RGMII TX/RX delay
 	 *
 	 * The Realtek vendor driver indicates the following possible
@@ -798,7 +821,7 @@ static int rtl8365mb_ext_config_rgmii(struct realtek_priv *priv, int port,
 			tx_delay = val / 2;
 		else
 			dev_warn(priv->dev,
-				 "EXT port TX delay must be 0 or 2 ns\n");
+				 "EXT interface TX delay must be 0 or 2 ns\n");
 	}
 
 	if (!of_property_read_u32(dn, "rx-internal-delay-ps", &val)) {
@@ -808,11 +831,11 @@ static int rtl8365mb_ext_config_rgmii(struct realtek_priv *priv, int port,
 			rx_delay = val;
 		else
 			dev_warn(priv->dev,
-				 "EXT port RX delay must be 0 to 2.1 ns\n");
+				 "EXT interface RX delay must be 0 to 2.1 ns\n");
 	}
 
 	ret = regmap_update_bits(
-		priv->map, RTL8365MB_EXT_RGMXF_REG(ext_port),
+		priv->map, RTL8365MB_EXT_RGMXF_REG(ext_int),
 		RTL8365MB_EXT_RGMXF_TXDELAY_MASK |
 			RTL8365MB_EXT_RGMXF_RXDELAY_MASK,
 		FIELD_PREP(RTL8365MB_EXT_RGMXF_TXDELAY_MASK, tx_delay) |
@@ -821,11 +844,11 @@ static int rtl8365mb_ext_config_rgmii(struct realtek_priv *priv, int port,
 		return ret;
 
 	ret = regmap_update_bits(
-		priv->map, RTL8365MB_DIGITAL_INTERFACE_SELECT_REG(ext_port),
-		RTL8365MB_DIGITAL_INTERFACE_SELECT_MODE_MASK(ext_port),
+		priv->map, RTL8365MB_DIGITAL_INTERFACE_SELECT_REG(ext_int),
+		RTL8365MB_DIGITAL_INTERFACE_SELECT_MODE_MASK(ext_int),
 		RTL8365MB_EXT_PORT_MODE_RGMII
 			<< RTL8365MB_DIGITAL_INTERFACE_SELECT_MODE_OFFSET(
-				   ext_port));
+				   ext_int));
 	if (ret)
 		return ret;
 
@@ -841,14 +864,19 @@ static int rtl8365mb_ext_config_forcemode(struct realtek_priv *priv, int port,
 	u32 r_duplex;
 	u32 r_speed;
 	u32 r_link;
-	int ext_port;
+	int ext_int;
 	int val;
 	int ret;
 
-	if (port == priv->cpu_port) {
-		ext_port = 1;
-	} else {
-		dev_err(priv->dev, "only one EXT port is currently supported\n");
+	if (port != priv->cpu_port) {
+		dev_err(priv->dev, "only one EXT interface is currently supported\n");
+		return -EINVAL;
+	}
+
+	ext_int = rtl8365mb_extint_port_map[port];
+
+	if (ext_int <= 0) {
+		dev_err(priv->dev, "Port %d is not an external interface port\n", port);
 		return -EINVAL;
 	}
 
@@ -898,7 +926,7 @@ static int rtl8365mb_ext_config_forcemode(struct realtek_priv *priv, int port,
 			 r_duplex) |
 	      FIELD_PREP(RTL8365MB_DIGITAL_INTERFACE_FORCE_SPEED_MASK, r_speed);
 	ret = regmap_write(priv->map,
-			   RTL8365MB_DIGITAL_INTERFACE_FORCE_REG(ext_port),
+			   RTL8365MB_DIGITAL_INTERFACE_FORCE_REG(ext_int),
 			   val);
 	if (ret)
 		return ret;
@@ -1831,10 +1859,6 @@ static int rtl8365mb_setup(struct dsa_switch *ds)
 		if (dsa_is_unused_port(priv->ds, i))
 			continue;
 
-		/* Set up per-port private data */
-		p->priv = priv;
-		p->index = i;
-
 		/* Forward only to the CPU */
 		ret = rtl8365mb_port_set_isolation(priv, i, BIT(priv->cpu_port));
 		if (ret)
@@ -1850,6 +1874,10 @@ static int rtl8365mb_setup(struct dsa_switch *ds)
 		 * administratively down by default.
 		 */
 		rtl8365mb_port_stp_state_set(priv->ds, i, BR_STATE_DISABLED);
+
+		/* Set up per-port private data */
+		p->priv = priv;
+		p->index = i;
 	}
 
 	/* Set maximum packet length to 1536 bytes */
