arm64: dts: rockchip: Add Edgeble NCM6A-IO M.2 M-Key

Edgeble NCM6A-IO board has M.2 M-Key via PCI3x4.

Add support for it.
Signed-off-by: Jagan Teki <jagan@edgeble.ai>
Link: https://lore.kernel.org/r/20231125190522.87607-8-jagan@edgeble.aiSigned-off-by: Heiko Stuebner <heiko@sntech.de>

arch/arm64/boot/dts/rockchip/rk3588-edgeble-neu6a-io.dtsi

@@ -18,6 +18,19 @@ vcc3v3_pcie2x1l0: vcc3v3-pcie2x1l0-regulator {
 		startup-delay-us = <5000>;
 		vin-supply = <&vcc_3v3_s3>;
 	};
+
+	vcc3v3_pcie3x4: vcc3v3-pcie3x4-regulator {
+		compatible = "regulator-fixed";
+		enable-active-high;
+		gpios = <&gpio2 RK_PC5 GPIO_ACTIVE_HIGH>; /* PCIE30x4_PWREN_H */
+		pinctrl-names = "default";
+		pinctrl-0 = <&pcie3x4_vcc3v3_en>;
+		regulator-name = "vcc3v3_pcie3x4";
+		regulator-min-microvolt = <3300000>;
+		regulator-max-microvolt = <3300000>;
+		startup-delay-us = <5000>;
+		vin-supply = <&vcc5v0_sys>;
+	};
 };
 
 &combphy0_ps {
@@ -53,6 +66,19 @@ &pcie2x1l0 {
 	status = "okay";
 };
 
+&pcie30phy {
+	status = "okay";
+};
+
+/* M-Key */
+&pcie3x4 {
+	pinctrl-names = "default";
+	pinctrl-0 = <&pcie3x4_rst>;
+	reset-gpios = <&gpio4 RK_PB0 GPIO_ACTIVE_HIGH>; /* PCIE30X2_PERSTn_M1_L */
+	vpcie3v3-supply = <&vcc3v3_pcie3x4>;
+	status = "okay";
+};
+
 &pinctrl {
 	pcie2 {
 		pcie2_0_rst: pcie2-0-rst {
@@ -60,6 +86,16 @@ pcie2_0_rst: pcie2-0-rst {
 		};
 	};
 
+	pcie3 {
+		pcie3x4_rst: pcie3x4-rst {
+			rockchip,pins = <4 RK_PB0 RK_FUNC_GPIO &pcfg_pull_none>;
+		};
+
+		pcie3x4_vcc3v3_en: pcie3x4-vcc3v3-en {
+			rockchip,pins = <2 RK_PC5 RK_FUNC_GPIO &pcfg_pull_none>;
+		};
+	};
+
 	hym8563 {
 		hym8563_int: hym8563-int {
 			rockchip,pins = <0 RK_PB0 RK_FUNC_GPIO &pcfg_pull_none>;