arm64: dts: ti: k3-j784s4: Add overlay for dual port USXGMII mode

The CPSW9G instance of the CPSW Ethernet Switch supports USXGMII mode
with MAC Ports 1 and 2 of the instance, which are connected to ENET
Expansion 1 and ENET Expansion 2 slots on the EVM respectively, through
the Serdes2 instance of the SERDES.

Enable CPSW9G MAC Ports 1 and 2 in fixed-link configuration USXGMII mode
at 5 Gbps each.
Signed-off-by: Siddharth Vadapalli <s-vadapalli@ti.com>
Signed-off-by: Chintan Vankar <c-vankar@ti.com>
Link: https://lore.kernel.org/r/20240502091002.3659435-6-c-vankar@ti.comSigned-off-by: Vignesh Raghavendra <vigneshr@ti.com>

arch/arm64/boot/dts/ti/Makefile

@@ -102,6 +102,7 @@ dtb-$(CONFIG_ARCH_K3) += k3-j722s-evm.dtb
 dtb-$(CONFIG_ARCH_K3) += k3-am69-sk.dtb
 dtb-$(CONFIG_ARCH_K3) += k3-j784s4-evm.dtb
 dtb-$(CONFIG_ARCH_K3) += k3-j784s4-evm-quad-port-eth-exp1.dtbo
+dtb-$(CONFIG_ARCH_K3) += k3-j784s4-evm-usxgmii-exp1-exp2.dtbo
 
 # Build time test only, enabled by CONFIG_OF_ALL_DTBS
 k3-am625-beagleplay-csi2-ov5640-dtbs := k3-am625-beagleplay.dtb \
@@ -151,6 +152,8 @@ k3-j721s2-evm-pcie1-ep-dtbs := k3-j721s2-common-proc-board.dtb \
 	k3-j721s2-evm-pcie1-ep.dtbo
 k3-j784s4-evm-quad-port-eth-exp1-dtbs := k3-j784s4-evm.dtb \
 	k3-j784s4-evm-quad-port-eth-exp1.dtbo
+k3-j784s4-evm-usxgmii-exp1-exp2-dtbs := k3-j784s4-evm.dtb \
+	k3-j784s4-evm-usxgmii-exp1-exp2.dtbo
 dtb- += k3-am625-beagleplay-csi2-ov5640.dtb \
 	k3-am625-beagleplay-csi2-tevi-ov5640.dtb \
 	k3-am625-sk-csi2-imx219.dtb \
@@ -172,7 +175,8 @@ dtb- += k3-am625-beagleplay-csi2-ov5640.dtb \
 	k3-j721e-evm-pcie0-ep.dtb \
 	k3-j721e-sk-csi2-dual-imx219.dtb \
 	k3-j721s2-evm-pcie1-ep.dtb \
-	k3-j784s4-evm-quad-port-eth-exp1.dtb
+	k3-j784s4-evm-quad-port-eth-exp1.dtb \
+	k3-j784s4-evm-usxgmii-exp1-exp2.dtb
 
 # Enable support for device-tree overlays
 DTC_FLAGS_k3-am625-beagleplay += -@

arch/arm64/boot/dts/ti/k3-j784s4-evm-usxgmii-exp1-exp2.dtso

+/* SPDX-License-Identifier: GPL-2.0-only OR MIT */
+/**
+ * DT Overlay for CPSW9G in dual port fixed-link USXGMII mode using ENET-1
+ * and ENET-2 Expansion slots of J784S4 EVM.
+ *
+ * Copyright (C) 2024 Texas Instruments Incorporated - https://www.ti.com/
+ */
+
+/dts-v1/;
+/plugin/;
+
+#include <dt-bindings/gpio/gpio.h>
+#include <dt-bindings/phy/phy-cadence.h>
+#include <dt-bindings/phy/phy.h>
+
+#include "k3-serdes.h"
+
+&{/} {
+	aliases {
+		ethernet1 = "/bus@100000/ethernet@c000000/ethernet-ports/port@1";
+		ethernet2 = "/bus@100000/ethernet@c000000/ethernet-ports/port@2";
+		ethernet3 = "/bus@100000/ethernet@c200000/ethernet-ports/port@1";
+	};
+};
+
+&main_cpsw0 {
+	pinctrl-names = "default";
+	status = "okay";
+};
+
+&main_cpsw0_port1 {
+	phy-mode = "usxgmii";
+	mac-address = [00 00 00 00 00 00];
+	phys = <&cpsw0_phy_gmii_sel 1>, <&serdes2_usxgmii_link>;
+	phy-names = "mac", "serdes";
+	status = "okay";
+	fixed-link {
+		speed = <5000>;
+		full-duplex;
+	};
+};
+
+&main_cpsw0_port2 {
+	phy-mode = "usxgmii";
+	mac-address = [00 00 00 00 00 00];
+	phys = <&cpsw0_phy_gmii_sel 2>, <&serdes2_usxgmii_link>;
+	phy-names = "mac", "serdes";
+	status = "okay";
+	fixed-link {
+		speed = <5000>;
+		full-duplex;
+	};
+};
+
+&serdes_wiz2 {
+	assigned-clock-parents = <&k3_clks 406 9>; /* Use 156.25 MHz clock for USXGMII */
+	status = "okay";
+};
+
+&serdes2 {
+	#address-cells = <1>;
+	#size-cells = <0>;
+	status = "okay";
+
+	serdes2_usxgmii_link: phy@2 {
+		reg = <2>;
+		cdns,num-lanes = <2>;
+		#phy-cells = <0>;
+		cdns,phy-type = <PHY_TYPE_USXGMII>;
+		resets = <&serdes_wiz2 3>, <&serdes_wiz2 4>;
+	};
+};
+
+&serdes_ln_ctrl {
+	idle-states = <J784S4_SERDES0_LANE0_PCIE1_LANE0>, <J784S4_SERDES0_LANE1_PCIE1_LANE1>,
+		      <J784S4_SERDES0_LANE2_IP3_UNUSED>, <J784S4_SERDES0_LANE3_USB>,
+		      <J784S4_SERDES1_LANE0_PCIE0_LANE0>, <J784S4_SERDES1_LANE1_PCIE0_LANE1>,
+		      <J784S4_SERDES1_LANE2_PCIE0_LANE2>, <J784S4_SERDES1_LANE3_PCIE0_LANE3>,
+		      <J784S4_SERDES2_LANE0_IP2_UNUSED>, <J784S4_SERDES2_LANE1_IP2_UNUSED>,
+		      <J784S4_SERDES2_LANE2_QSGMII_LANE1>, <J784S4_SERDES2_LANE3_QSGMII_LANE2>;
+};