src/arm64/ti/k3-am642-phyboard-electra-pcie-usb2.dtso

// SPDX-License-Identifier: GPL-2.0-only OR MIT
/*
 * DT overlay for PCIe support (limits USB to 2.0/high-speed)
 *
 * Copyright (C) 2021 PHYTEC America, LLC - https://www.phytec.com
 * Author: Matt McKee <mmckee@phytec.com>
 *
 * Copyright (C) 2024 PHYTEC America, LLC - https://www.phytec.com
 * Author: Nathan Morrisson <nmorrisson@phytec.com>
 */

/dts-v1/;
/plugin/;

#include <dt-bindings/gpio/gpio.h>
#include <dt-bindings/phy/phy.h>
#include <dt-bindings/phy/phy-cadence.h>

#include "k3-pinctrl.h"
#include "k3-serdes.h"

&{/} {
	pcie_refclk0: pcie-refclk0 {
		compatible = "gpio-gate-clock";
		pinctrl-names = "default";
		pinctrl-0 = <&pcie_usb_sel_pins_default>;
		clocks = <&serdes_refclk>;
		#clock-cells = <0>;
		enable-gpios = <&main_gpio1 7 GPIO_ACTIVE_HIGH>;
	};
};

&main_pmx0 {
	pcie_usb_sel_pins_default: pcie-usb-sel-default-pins {
		pinctrl-single,pins = <
			AM64X_IOPAD(0x017c, PIN_OUTPUT, 7)	/* (T1) PRG0_PRU0_GPO7.GPIO1_7 */
		>;
	};

	pcie_pins_default: pcie-default-pins {
		pinctrl-single,pins = <
			AM64X_IOPAD(0x0098, PIN_OUTPUT, 7)	/* (W19) GPMC0_WAIT0.GPIO0_37 */
		>;
	};
};

&pcie0_rc {
	pinctrl-names = "default";
	pinctrl-0 = <&pcie_pins_default>;
	reset-gpios = <&main_gpio0 37 GPIO_ACTIVE_HIGH>;
	phys = <&serdes0_pcie_usb_link>;
	phy-names = "pcie-phy";
	num-lanes = <1>;
	status = "okay";
};

&serdes0_pcie_usb_link {
	cdns,phy-type = <PHY_TYPE_PCIE>;
};

&serdes_ln_ctrl {
	idle-states = <AM64_SERDES0_LANE0_PCIE0>;
};

&serdes0 {
	assigned-clock-parents = <&pcie_refclk0>, <&pcie_refclk0>, <&pcie_refclk0>;
};

&serdes_refclk {
	clock-frequency = <100000000>;
};

/*
 * Assign pcie_refclk0 to serdes_wiz0 as ext_ref_clk.
 * This makes sure that the clock generator gets enabled at the right time.
 */
&serdes_wiz0 {
	clocks = <&k3_clks 162 0>, <&k3_clks 162 1>, <&pcie_refclk0>;
};

&usbss0 {
	ti,usb2-only;
};

&usb0 {
	maximum-speed = "high-speed";
};