riscv: dts: spacemit: add DeepComputing FML13V05 board device tree

The FML13V05 board from DeepComputing incorporates a SpacemiT K3 RISC-V
SoC.It is a mainboard designed for the Framework Laptop 13 Chassis,
which has (Framework) SKU FRANHQ0001.

The FML13V05 board features:
- SpacemiT K3 RISC-V SoC
- LPDDR5 16GB or 32GB
- eMMC 32GB ~128GB (Optional)
- UFS 3.1 256G (Optional)
- QSPI Flash
- MicroSD Slot
- PCIe-based Wi-Fi
- 4 USB-C Ports
 - Port 1: PD 3.0 (65W Max), USB 3.2 Gen 1
 - Port 2: PD 3.0 (65W Max), USB 3.2 Gen 1, DP 1.4 (4K@60Hz)
 - Port 3 & 4: USB 3.2 Gen 1

This minimal device tree enables booting into a serial console with UART
output.

Signed-off-by: Sandie Cao <sandie.cao@deepcomputing.io>
Reviewed-by: Troy Mitchell <troy.mitchell@linux.spacemit.com>
Reviewed-by: Yixun Lan <dlan@kernel.org>
Link: https://lore.kernel.org/r/20260421064306.1583888-1-sandie.cao@deepcomputing.io
Signed-off-by: Yixun Lan <dlan@kernel.org>

arch/riscv/boot/dts/spacemit/Makefile

@@ -4,4 +4,5 @@ dtb-$(CONFIG_ARCH_SPACEMIT) += k1-milkv-jupiter.dtb
 dtb-$(CONFIG_ARCH_SPACEMIT) += k1-musepi-pro.dtb
 dtb-$(CONFIG_ARCH_SPACEMIT) += k1-orangepi-r2s.dtb
 dtb-$(CONFIG_ARCH_SPACEMIT) += k1-orangepi-rv2.dtb
+dtb-$(CONFIG_ARCH_SPACEMIT) += k3-deepcomputing-fml13v05.dtb
 dtb-$(CONFIG_ARCH_SPACEMIT) += k3-pico-itx.dtb

arch/riscv/boot/dts/spacemit/k3-deepcomputing-fml13v05.dts

@@ -0,0 +1,31 @@
+// SPDX-License-Identifier: (GPL-2.0 OR MIT)
+/*
+ * Copyright (C) 2026 DeepComputing (HK) Limited
+ */
+
+#include "k3.dtsi"
+#include "k3-pinctrl.dtsi"
+
+/ {
+	model = "DeepComputing FML13V05";
+	compatible = "deepcomputing,fml13v05", "spacemit,k3";
+
+	aliases {
+		serial0 = &uart0;
+	};
+
+	chosen {
+		stdout-path = "serial0";
+	};
+
+	memory@100000000 {
+		device_type = "memory";
+		reg = <0x1 0x00000000 0x4 0x00000000>;
+	};
+};
+
+&uart0 {
+	pinctrl-names = "default";
+	pinctrl-0 = <&uart0_0_cfg>;
+	status = "okay";
+};