diff --git a/Documentation/devicetree/bindings/net/dsa/ocelot.txt b/Documentation/devicetree/bindings/net/dsa/ocelot.txt
new file mode 100644
index 000000000000..66a129fea705
--- /dev/null
+++ b/Documentation/devicetree/bindings/net/dsa/ocelot.txt
@@ -0,0 +1,116 @@
+Microchip Ocelot switch driver family
+=====================================
+
+Felix
+-----
+
+The VSC9959 core is currently the only switch supported by the driver, and is
+found in the NXP LS1028A. It is a PCI device, part of the larger ENETC root
+complex. As a result, the ethernet-switch node is a sub-node of the PCIe root
+complex node and its "reg" property conforms to the parent node bindings:
+
+* reg: Specifies PCIe Device Number and Function Number of the endpoint device,
+  in this case for the Ethernet L2Switch it is PF5 (of device 0, bus 0).
+
+It does not require a "compatible" string.
+
+The interrupt line is used to signal availability of PTP TX timestamps and for
+TSN frame preemption.
+
+For the external switch ports, depending on board configuration, "phy-mode" and
+"phy-handle" are populated by board specific device tree instances. Ports 4 and
+5 are fixed as internal ports in the NXP LS1028A instantiation.
+
+The CPU port property ("ethernet") configures the feature called "NPI port" in
+the Ocelot hardware core. The CPU port in Ocelot is a set of queues, which are
+connected, in the Node Processor Interface (NPI) mode, to an Ethernet port.
+By default, in fsl-ls1028a.dtsi, the NPI port is assigned to the internal
+2.5Gbps port@4, but can be moved to the 1Gbps port@5, depending on the specific
+use case.  Moving the NPI port to an external switch port is hardware possible,
+but there is no platform support for the Linux system on the LS1028A chip to
+operate as an entire slave DSA chip.  NPI functionality (and therefore DSA
+tagging) is supported on a single port at a time.
+
+Any port can be disabled (and in fsl-ls1028a.dtsi, they are indeed all disabled
+by default, and should be enabled on a per-board basis). But if any external
+switch port is enabled at all, the ENETC PF2 (enetc_port2) should be enabled as
+well, regardless of whether it is configured as the DSA master or not. This is
+because the Felix PHYLINK implementation accesses the MAC PCS registers, which
+in hardware truly belong to the ENETC port #2 and not to Felix.
+
+Supported PHY interface types (appropriate SerDes protocol setting changes are
+needed in the RCW binary):
+
+* phy_mode = "internal": on ports 4 and 5
+* phy_mode = "sgmii": on ports 0, 1, 2, 3
+* phy_mode = "qsgmii": on ports 0, 1, 2, 3
+* phy_mode = "usxgmii": on ports 0, 1, 2, 3
+* phy_mode = "2500base-x": on ports 0, 1, 2, 3
+
+For the rest of the device tree binding definitions, which are standard DSA and
+PCI, refer to the following documents:
+
+Documentation/devicetree/bindings/net/dsa/dsa.txt
+Documentation/devicetree/bindings/pci/pci.txt
+
+Example:
+
+&soc {
+	pcie@1f0000000 { /* Integrated Endpoint Root Complex */
+		ethernet-switch@0,5 {
+			reg = <0x000500 0 0 0 0>;
+			/* IEP INT_B */
+			interrupts = <GIC_SPI 95 IRQ_TYPE_LEVEL_HIGH>;
+
+			ports {
+				#address-cells = <1>;
+				#size-cells = <0>;
+
+				/* External ports */
+				port@0 {
+					reg = <0>;
+					label = "swp0";
+				};
+
+				port@1 {
+					reg = <1>;
+					label = "swp1";
+				};
+
+				port@2 {
+					reg = <2>;
+					label = "swp2";
+				};
+
+				port@3 {
+					reg = <3>;
+					label = "swp3";
+				};
+
+				/* Tagging CPU port */
+				port@4 {
+					reg = <4>;
+					ethernet = <&enetc_port2>;
+					phy-mode = "internal";
+
+					fixed-link {
+						speed = <2500>;
+						full-duplex;
+					};
+				};
+
+				/* Non-tagging CPU port */
+				port@5 {
+					reg = <5>;
+					phy-mode = "internal";
+					status = "disabled";
+
+					fixed-link {
+						speed = <1000>;
+						full-duplex;
+					};
+				};
+			};
+		};
+	};
+};
diff --git a/drivers/net/dsa/ocelot/felix.c b/drivers/net/dsa/ocelot/felix.c
index 3257962c147e..35124ef7e75b 100644
--- a/drivers/net/dsa/ocelot/felix.c
+++ b/drivers/net/dsa/ocelot/felix.c
@@ -176,8 +176,7 @@ static void felix_phylink_validate(struct dsa_switch *ds, int port,
 	phylink_set(mask, 100baseT_Full);
 	phylink_set(mask, 1000baseT_Full);
 
-	/* The internal ports that run at 2.5G are overclocked GMII */
-	if (state->interface == PHY_INTERFACE_MODE_GMII ||
+	if (state->interface == PHY_INTERFACE_MODE_INTERNAL ||
 	    state->interface == PHY_INTERFACE_MODE_2500BASEX ||
 	    state->interface == PHY_INTERFACE_MODE_USXGMII) {
 		phylink_set(mask, 2500baseT_Full);
diff --git a/drivers/net/dsa/ocelot/felix_vsc9959.c b/drivers/net/dsa/ocelot/felix_vsc9959.c
index 2c812b481778..93800e81cdd4 100644
--- a/drivers/net/dsa/ocelot/felix_vsc9959.c
+++ b/drivers/net/dsa/ocelot/felix_vsc9959.c
@@ -955,8 +955,7 @@ static int vsc9959_prevalidate_phy_mode(struct ocelot *ocelot, int port,
 					phy_interface_t phy_mode)
 {
 	switch (phy_mode) {
-	case PHY_INTERFACE_MODE_GMII:
-		/* Only supported on internal to-CPU ports */
+	case PHY_INTERFACE_MODE_INTERNAL:
 		if (port != 4 && port != 5)
 			return -ENOTSUPP;
 		return 0;