[PATCH 2/3] arm: dts: add U-Boot overrides for Genio 520 and 720 SD card

[David Lechner]

Add U-Boot-specific device tree overrides for the Genio 520 and 720 EVK
boards. These are needed to enable SD card support in U-Boot due to
current driver limitations. It is expected that these files will remain
after eventually converting these to CONFIG_OF_UPSTREAM, so we use
separate .u-boot.dtsi files for this.

Signed-off-by: David Lechner <dlechner at baylibre.com>
---
 arch/arm/dts/mt8371-genio-520-evk-u-boot.dtsi |  3 +++
 arch/arm/dts/mt8371-genio-common-u-boot.dtsi  | 28 +++++++++++++++++++++++++++
 arch/arm/dts/mt8391-genio-720-evk-u-boot.dtsi |  3 +++
 board/mediatek/MAINTAINERS                    |  3 +++
 4 files changed, 37 insertions(+)

diff --git a/arch/arm/dts/mt8371-genio-520-evk-u-boot.dtsi b/arch/arm/dts/mt8371-genio-520-evk-u-boot.dtsi
new file mode 100644
index 00000000000..a69e2db5a04
--- /dev/null
+++ b/arch/arm/dts/mt8371-genio-520-evk-u-boot.dtsi
@@ -0,0 +1,3 @@
+// SPDX-License-Identifier: (GPL-2.0-only OR MIT)
+
+#include "mt8371-genio-common-u-boot.dtsi"
diff --git a/arch/arm/dts/mt8371-genio-common-u-boot.dtsi b/arch/arm/dts/mt8371-genio-common-u-boot.dtsi
new file mode 100644
index 00000000000..b7a0c0a82a7
--- /dev/null
+++ b/arch/arm/dts/mt8371-genio-common-u-boot.dtsi
@@ -0,0 +1,28 @@
+// SPDX-License-Identifier: (GPL-2.0-only OR MIT)
+/*
+ * Copyright (C) 2026 MediaTek Inc.
+ */
+
+&mmc1 {
+	/* U-Boot driver doesn't support UHS yet. */
+	/delete-property/ sd-uhs-sdr50;
+	/delete-property/ sd-uhs-sdr104;
+	mmc-no-1-8-v;
+};
+
+/*
+ * Needed to trigger U-Boot auto-set-voltage. Default voltages for these
+ * supplies at boot are incorrect and U-Boot MMC drivers don't set them.
+ */
+
+&mt6359_vpa_buck_reg {
+	regulator-min-microvolt = <3000000>;
+	regulator-max-microvolt = <3000000>;
+	regulator-always-on;
+};
+
+&mt6359_vsim1_ldo_reg {
+	regulator-min-microvolt = <3000000>;
+	regulator-max-microvolt = <3000000>;
+	regulator-always-on;
+};
diff --git a/arch/arm/dts/mt8391-genio-720-evk-u-boot.dtsi b/arch/arm/dts/mt8391-genio-720-evk-u-boot.dtsi
new file mode 100644
index 00000000000..a69e2db5a04
--- /dev/null
+++ b/arch/arm/dts/mt8391-genio-720-evk-u-boot.dtsi
@@ -0,0 +1,3 @@
+// SPDX-License-Identifier: (GPL-2.0-only OR MIT)
+
+#include "mt8371-genio-common-u-boot.dtsi"
diff --git a/board/mediatek/MAINTAINERS b/board/mediatek/MAINTAINERS
index 4f371592059..49041c8899b 100644
--- a/board/mediatek/MAINTAINERS
+++ b/board/mediatek/MAINTAINERS
@@ -1,6 +1,9 @@
 MT8189/MT8371/MT8391 EVK
 M:	Macpaul Lin <macpaul.lin at mediatek.com>
 S:	Maintained
+F:	arch/arm/dts/mt8371-genio-520-evk-u-boot.dtsi
+F:	arch/arm/dts/mt8371-genio-common-u-boot.dtsi
+F:	arch/arm/dts/mt8391-genio-720-evk-u-boot.dtsi
 F:	configs/mt8189.config
 F:	configs/mt8371_genio_520_evk_defconfig
 F:	configs/mt8391_genio_720_evk_defconfig

-- 
2.43.0