[PATCH 2/3] riscv: milkv_duo: Use upstream devicetree

[Zhuxu Ran]

Switch Milk-V Duo to the upstream CV1800B devicetree by enabling
CONFIG_OF_UPSTREAM and selecting sophgo/cv1800b-milkv-duo.

The upstream devicetree keeps the Ethernet MAC disabled. Add a
small U-Boot override to keep the existing U-Boot networking
support enabled.

Signed-off-by: Zhuxu Ran <zhuxu_ran at zohomail.com>
---
 arch/riscv/dts/cv1800b-milkv-duo-u-boot.dtsi | 12 ++++++++++++
 configs/milkv_duo_defconfig                  |  3 ++-
 2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/arch/riscv/dts/cv1800b-milkv-duo-u-boot.dtsi b/arch/riscv/dts/cv1800b-milkv-duo-u-boot.dtsi
new file mode 100644
index 00000000000..158b02a543a
--- /dev/null
+++ b/arch/riscv/dts/cv1800b-milkv-duo-u-boot.dtsi
@@ -0,0 +1,12 @@
+// SPDX-License-Identifier: (GPL-2.0 OR MIT)
+/*
+ * U-Boot overrides for Milk-V Duo.
+ *
+ * The upstream Linux device tree describes the CV1800B Ethernet MAC, but
+ * keeps it disabled. Enable it here to preserve the existing U-Boot
+ * networking support when using the upstream device tree.
+ */
+
+&gmac0 {
+	status = "okay";
+};
diff --git a/configs/milkv_duo_defconfig b/configs/milkv_duo_defconfig
index f1f3930564b..9d6b80362d5 100644
--- a/configs/milkv_duo_defconfig
+++ b/configs/milkv_duo_defconfig
@@ -4,7 +4,8 @@ CONFIG_SYS_MALLOC_F_LEN=0x8000
 CONFIG_NR_DRAM_BANKS=1
 CONFIG_HAS_CUSTOM_SYS_INIT_SP_ADDR=y
 CONFIG_CUSTOM_SYS_INIT_SP_ADDR=0x82300000
-CONFIG_DEFAULT_DEVICE_TREE="cv1800b-milkv-duo"
+CONFIG_DEFAULT_DEVICE_TREE="sophgo/cv1800b-milkv-duo"
+CONFIG_OF_UPSTREAM=y
 CONFIG_SYS_LOAD_ADDR=0x80080000
 CONFIG_IDENT_STRING="milkv_duo"
 CONFIG_TARGET_MILKV_DUO=y

-- 
2.55.0