[PATCH v5 7/7] riscv: dts: spacemit: add K3 Pico-ITX board support

[Guodong Xu <guodong@riscstar.com>]

K3 Pico-ITX is a 2.5-inch single-board computer equipted with a SpacemiT
K3 SoC.

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

Signed-off-by: Guodong Xu <guodong@riscstar.com>
---
v5: Update the commit message subject per Yixun's suggestion.
    Remove the unused aliases.
    Update the copyright year to 2026.
v4: No change.
v3: No change.
v2: Add aliases node in this board DT.
    Update the memory node to reflect the hardware truth. Address
     starts at 0x100000000 (4G) boundary.
---
 arch/riscv/boot/dts/spacemit/Makefile        |  1 +
 arch/riscv/boot/dts/spacemit/k3-pico-itx.dts | 29 ++++++++++++++++++++++++++++
 2 files changed, 30 insertions(+)

diff --git a/arch/riscv/boot/dts/spacemit/Makefile b/arch/riscv/boot/dts/spacemit/Makefile
index 95889e7269d1..7e2b87702571 100644
--- a/arch/riscv/boot/dts/spacemit/Makefile
+++ b/arch/riscv/boot/dts/spacemit/Makefile
@@ -4,3 +4,4 @@ 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-pico-itx.dtb
diff --git a/arch/riscv/boot/dts/spacemit/k3-pico-itx.dts b/arch/riscv/boot/dts/spacemit/k3-pico-itx.dts
new file mode 100644
index 000000000000..b691304d4b74
--- /dev/null
+++ b/arch/riscv/boot/dts/spacemit/k3-pico-itx.dts
@@ -0,0 +1,29 @@
+// SPDX-License-Identifier: (GPL-2.0 OR MIT)
+/*
+ * Copyright (c) 2026 SpacemiT (Hangzhou) Technology Co. Ltd
+ * Copyright (c) 2026 Guodong Xu <guodong@riscstar.com>
+ */
+
+#include "k3.dtsi"
+
+/ {
+	model = "SpacemiT K3 Pico-ITX";
+	compatible = "spacemit,k3-pico-itx", "spacemit,k3";
+
+	aliases {
+		serial0 = &uart0;
+	};
+
+	chosen {
+		stdout-path = "serial0";
+	};
+
+	memory@100000000 {
+		device_type = "memory";
+		reg = <0x1 0x00000000 0x4 0x00000000>;
+	};
+};
+
+&uart0 {
+	status = "okay";
+};

-- 
2.43.0