boards: imx8mp_evk: add i2c support

Added i2c3 support on imx8mp_evk A53 board.

Signed-off-by: Jiafei Pan <[email protected]>

Author: JiafeiPan

boards/nxp/imx8mp_evk/imx8mp_evk-pinctrl.dtsi

@@ -66,4 +66,16 @@
 			drive-strength = "x1";
 		};
 	};
+
+	pinmux_i2c3: pinmux_i2c3 {
+		group0 {
+			pinmux = <&iomuxc_i2c3_scl_i2c_scl_i2c3_scl>,
+				<&iomuxc_i2c3_sda_i2c_sda_i2c3_sda>;
+			bias-pull-up;
+			input-schmitt-enable;
+			slew-rate = "slow";
+			drive-strength = "x4";
+			input-enable;
+		};
+	};
 };

boards/nxp/imx8mp_evk/imx8mp_evk_mimx8ml8_a53.dts

@@ -6,6 +6,7 @@
 
 /dts-v1/;
 
+#include <zephyr/dt-bindings/i2c/i2c.h>
 #include <nxp/nxp_mimx8mp_a53.dtsi>
 #include "imx8mp_evk-pinctrl.dtsi"
 
@@ -69,3 +70,10 @@
 	pinctrl-0 = <&uart4_default>;
 	pinctrl-names = "default";
 };
+
+&i2c3 {
+	status = "okay";
+	pinctrl-0 = <&pinmux_i2c3>;
+	pinctrl-names = "default";
+	clock-frequency = <I2C_BITRATE_STANDARD>;
+};

soc/nxp/imx/imx8m/a53/soc.c

@@ -45,14 +45,32 @@ static void soc_rdc_init(void)
 	periphConfig.policy = RDC_DT_VAL(enet);
 	RDC_SetPeriphAccessConfig(rdc_inst, &periphConfig);
 #endif
+
+#if DT_NODE_HAS_STATUS_OKAY(DT_NODELABEL(i2c3)) && DT_NODE_HAS_PROP(DT_NODELABEL(i2c3), rdc)
+	periphConfig.periph = kRDC_Periph_I2C3;
+	periphConfig.policy = RDC_DT_VAL(i2c3);
+	RDC_SetPeriphAccessConfig(rdc_inst, &periphConfig);
+#endif
 }
 #else
 
 #define soc_rdc_init() do { } while (false)
 
 #endif
 
+static void soc_clock_init(void)
+{
+#if DT_NODE_HAS_STATUS_OKAY(DT_NODELABEL(i2c3))
+	/* Set I2C source to SysPLL1 Div5 160MHZ */
+	CLOCK_SetRootMux(kCLOCK_RootI2c3, kCLOCK_I2cRootmuxSysPll1Div5);
+	/* Set root clock to 160MHZ / 10 = 16MHZ */
+	CLOCK_SetRootDivider(kCLOCK_RootI2c3, 1U, 10U);
+	CLOCK_EnableClock(kCLOCK_I2c3);
+#endif
+}
+
 void soc_prep_hook(void)
 {
 	soc_rdc_init();
+	soc_clock_init();
 }