arm64: dts: renesas: rzg3s-smarc-som: Enable the Ethernet interfaces

The RZ/G3S Smarc Module has Ethernet PHYs (KSZ9131) connected to each
Ethernet IP.  For this, add proper DT descriptions to enable Ethernet
communication through these PHYs.

The interface b/w PHYs and MACs is RGMII.  The skew settings were set to
zero as based on phy-mode (rgmii-id) the KSZ9131 driver enables internal
DLL, which adds a 2ns delay b/w clocks (TX/RX) and data signals.

Different pin settings were applied to TXC and TX_CTL compared with the
rest of the RGMII pins to comply with requirements for these pins
imposed by HW manual of RZ/G3S (see chapters "Ether Ch0 Voltage Mode
Control Register (ETH0_POC)", "Ether Ch1 Voltage Mode Control Register
(ETH1_POC)", for power source selection, "Ether MII/RGMII Mode Control
Register (ETH_MODE)" for output-enable and "Input Enable Control
Register (IEN_m)" for input-enable configurations).

Also enable the Ethernet interfaces by selecting SW_CONFIG3 = SW_ON.
Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20231207070700.4156557-12-claudiu.beznea.uj@bp.renesas.comSigned-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

arch/arm64/boot/dts/renesas/rzg3s-smarc-som.dtsi

@@ -26,7 +26,7 @@
  *	SW_ON  - SCIF1, SSI0, IRQ0, IRQ1 connected to SoC
  */
 #define SW_CONFIG2	SW_ON
-#define SW_CONFIG3	SW_OFF
+#define SW_CONFIG3	SW_ON
 
 / {
 	compatible = "renesas,rzg3s-smarcm", "renesas,r9a08g045s33", "renesas,r9a08g045";
@@ -35,6 +35,9 @@ aliases {
 		mmc0 = &sdhi0;
 #if SW_CONFIG3 == SW_OFF
 		mmc2 = &sdhi2;
+#else
+		eth0 = &eth0;
+		eth1 = &eth1;
 #endif
 	};
 
@@ -89,6 +92,60 @@ vcc_sdhi2: regulator2 {
 	};
 };
 
+#if SW_CONFIG3 == SW_ON
+&eth0 {
+	pinctrl-0 = <&eth0_pins>;
+	pinctrl-names = "default";
+	phy-handle = <&phy0>;
+	phy-mode = "rgmii-id";
+	status = "okay";
+
+	phy0: ethernet-phy@7 {
+		reg = <7>;
+		interrupt-parent = <&pinctrl>;
+		interrupts = <RZG2L_GPIO(12, 0) IRQ_TYPE_EDGE_FALLING>;
+		rxc-skew-psec = <0>;
+		txc-skew-psec = <0>;
+		rxdv-skew-psec = <0>;
+		txen-skew-psec = <0>;
+		rxd0-skew-psec = <0>;
+		rxd1-skew-psec = <0>;
+		rxd2-skew-psec = <0>;
+		rxd3-skew-psec = <0>;
+		txd0-skew-psec = <0>;
+		txd1-skew-psec = <0>;
+		txd2-skew-psec = <0>;
+		txd3-skew-psec = <0>;
+	};
+};
+
+&eth1 {
+	pinctrl-0 = <&eth1_pins>;
+	pinctrl-names = "default";
+	phy-handle = <&phy1>;
+	phy-mode = "rgmii-id";
+	status = "okay";
+
+	phy1: ethernet-phy@7 {
+		reg = <7>;
+		interrupt-parent = <&pinctrl>;
+		interrupts = <RZG2L_GPIO(12, 1) IRQ_TYPE_EDGE_FALLING>;
+		rxc-skew-psec = <0>;
+		txc-skew-psec = <0>;
+		rxdv-skew-psec = <0>;
+		txen-skew-psec = <0>;
+		rxd0-skew-psec = <0>;
+		rxd1-skew-psec = <0>;
+		rxd2-skew-psec = <0>;
+		rxd3-skew-psec = <0>;
+		txd0-skew-psec = <0>;
+		txd1-skew-psec = <0>;
+		txd2-skew-psec = <0>;
+		txd3-skew-psec = <0>;
+	};
+};
+#endif
+
 &extal_clk {
 	clock-frequency = <24000000>;
 };
@@ -136,6 +193,88 @@ &sdhi2 {
 #endif
 
 &pinctrl {
+	eth0-phy-irq-hog {
+		gpio-hog;
+		gpios = <RZG2L_GPIO(12, 0) GPIO_ACTIVE_LOW>;
+		input;
+		line-name = "eth0-phy-irq";
+	};
+
+	eth0_pins: eth0 {
+		txc {
+			pinmux = <RZG2L_PORT_PINMUX(1, 0, 1)>;  /* ET0_TXC */
+			power-source = <1800>;
+			output-enable;
+			input-enable;
+			drive-strength-microamp = <5200>;
+		};
+
+		tx_ctl {
+			pinmux = <RZG2L_PORT_PINMUX(1, 1, 1)>;  /* ET0_TX_CTL */
+			power-source = <1800>;
+			output-enable;
+			drive-strength-microamp = <5200>;
+		};
+
+		mux {
+			pinmux = <RZG2L_PORT_PINMUX(1, 2, 1)>,	/* ET0_TXD0 */
+				 <RZG2L_PORT_PINMUX(1, 3, 1)>,	/* ET0_TXD1 */
+				 <RZG2L_PORT_PINMUX(1, 4, 1)>,	/* ET0_TXD2 */
+				 <RZG2L_PORT_PINMUX(2, 0, 1)>,	/* ET0_TXD3 */
+				 <RZG2L_PORT_PINMUX(3, 0, 1)>,	/* ET0_RXC */
+				 <RZG2L_PORT_PINMUX(3, 1, 1)>,	/* ET0_RX_CTL */
+				 <RZG2L_PORT_PINMUX(3, 2, 1)>,	/* ET0_RXD0 */
+				 <RZG2L_PORT_PINMUX(3, 3, 1)>,	/* ET0_RXD1 */
+				 <RZG2L_PORT_PINMUX(4, 0, 1)>,	/* ET0_RXD2 */
+				 <RZG2L_PORT_PINMUX(4, 1, 1)>,	/* ET0_RXD3 */
+				 <RZG2L_PORT_PINMUX(4, 3, 1)>,	/* ET0_MDC */
+				 <RZG2L_PORT_PINMUX(4, 4, 1)>,	/* ET0_MDIO */
+				 <RZG2L_PORT_PINMUX(4, 5, 1)>;	/* ET0_LINKSTA */
+			power-source = <1800>;
+		};
+	};
+
+	eth1-phy-irq-hog {
+		gpio-hog;
+		gpios = <RZG2L_GPIO(12, 1) GPIO_ACTIVE_LOW>;
+		input;
+		line-name = "eth1-phy-irq";
+	};
+
+	eth1_pins: eth1 {
+		txc {
+			pinmux = <RZG2L_PORT_PINMUX(7, 0, 1)>;	/* ET1_TXC */
+			power-source = <1800>;
+			output-enable;
+			input-enable;
+			drive-strength-microamp = <5200>;
+		};
+
+		tx_ctl {
+			pinmux = <RZG2L_PORT_PINMUX(7, 1, 1)>;	/* ET1_TX_CTL */
+			power-source = <1800>;
+			output-enable;
+			drive-strength-microamp = <5200>;
+		};
+
+		mux {
+			pinmux = <RZG2L_PORT_PINMUX(7, 2, 1)>,	/* ET1_TXD0 */
+				 <RZG2L_PORT_PINMUX(7, 3, 1)>,	/* ET1_TXD1 */
+				 <RZG2L_PORT_PINMUX(7, 4, 1)>,	/* ET1_TXD2 */
+				 <RZG2L_PORT_PINMUX(8, 0, 1)>,	/* ET1_TXD3 */
+				 <RZG2L_PORT_PINMUX(8, 4, 1)>,	/* ET1_RXC */
+				 <RZG2L_PORT_PINMUX(9, 0, 1)>,	/* ET1_RX_CTL */
+				 <RZG2L_PORT_PINMUX(9, 1, 1)>,	/* ET1_RXD0 */
+				 <RZG2L_PORT_PINMUX(9, 2, 1)>,	/* ET1_RXD1 */
+				 <RZG2L_PORT_PINMUX(9, 3, 1)>,	/* ET1_RXD2 */
+				 <RZG2L_PORT_PINMUX(10, 0, 1)>,	/* ET1_RXD3 */
+				 <RZG2L_PORT_PINMUX(10, 2, 1)>,	/* ET1_MDC */
+				 <RZG2L_PORT_PINMUX(10, 3, 1)>,	/* ET1_MDIO */
+				 <RZG2L_PORT_PINMUX(10, 4, 1)>;	/* ET1_LINKSTA */
+			power-source = <1800>;
+		};
+	};
+
 	sdhi0_pins: sd0 {
 		data {
 			pins = "SD0_DATA0", "SD0_DATA1", "SD0_DATA2", "SD0_DATA3";