feat(stm32mp2-fdts): add stm32mp257f-ev1 board

Add STM32MP257F Evaluation board support. It embeds a STM32MP257FAI
SoC, with 4GB of DDR4, TSN switch (2+1 ports), 2*USB typeA, 1*USB2
typeC, SNOR OctoSPI, mini PCIe, STPMIC2 for power distribution ...

Signed-off-by: Alexandre Torgue <alexandre.torgue@foss.st.com>
Signed-off-by: Yann Gautier <yann.gautier@st.com>
Change-Id: I92da3a7085a4d2f2d606777c4215aed55f77c589
diff --git a/fdts/stm32mp25-bl2.dtsi b/fdts/stm32mp25-bl2.dtsi
new file mode 100644
index 0000000..7a6bbbe
--- /dev/null
+++ b/fdts/stm32mp25-bl2.dtsi
@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-3-Clause)
+/*
+ * Copyright (C) 2023, STMicroelectronics - All Rights Reserved
+ */
+
+/omit-if-no-ref/ &usart2_pins_a;
diff --git a/fdts/stm32mp25-pinctrl.dtsi b/fdts/stm32mp25-pinctrl.dtsi
index 4147449..8d0eaaf 100644
--- a/fdts/stm32mp25-pinctrl.dtsi
+++ b/fdts/stm32mp25-pinctrl.dtsi
@@ -4,3 +4,18 @@
  * Author: Alexandre Torgue <alexandre.torgue@foss.st.com> for STMicroelectronics.
  */
 #include <dt-bindings/pinctrl/stm32-pinfunc.h>
+
+&pinctrl {
+	usart2_pins_a: usart2-0 {
+		pins1 {
+			pinmux = <STM32_PINMUX('A', 4, AF6)>; /* USART2_TX */
+			bias-disable;
+			drive-push-pull;
+			slew-rate = <0>;
+		};
+		pins2 {
+			pinmux = <STM32_PINMUX('A', 8, AF8)>; /* USART2_RX */
+			bias-disable;
+		};
+	};
+};
diff --git a/fdts/stm32mp257f-ev1.dts b/fdts/stm32mp257f-ev1.dts
new file mode 100644
index 0000000..916d1e2
--- /dev/null
+++ b/fdts/stm32mp257f-ev1.dts
@@ -0,0 +1,36 @@
+// SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-3-Clause)
+/*
+ * Copyright (C) 2023, STMicroelectronics - All Rights Reserved
+ * Author: Alexandre Torgue <alexandre.torgue@foss.st.com> for STMicroelectronics.
+ */
+
+/dts-v1/;
+
+#include "stm32mp257.dtsi"
+#include "stm32mp25xf.dtsi"
+#include "stm32mp25-pinctrl.dtsi"
+#include "stm32mp25xxai-pinctrl.dtsi"
+
+/ {
+	model = "STMicroelectronics STM32MP257F-EV1 Evaluation Board";
+	compatible = "st,stm32mp257f-ev1", "st,stm32mp257";
+
+	aliases {
+		serial0 = &usart2;
+	};
+
+	chosen {
+		stdout-path = "serial0:115200n8";
+	};
+
+	memory@80000000 {
+		device_type = "memory";
+		reg = <0x0 0x80000000 0x1 0x00000000>;
+	};
+};
+
+&usart2 {
+	pinctrl-names = "default";
+	pinctrl-0 = <&usart2_pins_a>;
+	status = "okay";
+};