arm: dts: add U-Boot overrides for Genio 520 and 720 SD card

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.

Reviewed-by: Julien Stephan <jstephan@baylibre.com>
Link: https://patch.msgid.link/20260316-mtk-ext-mmc-boot-v1-2-1aae51a44705@baylibre.com
Signed-off-by: David Lechner <dlechner@baylibre.com>

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 (file)
index 0000000..a69e2db
--- /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 (file)
index 0000000..b7a0c0a
--- /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 (file)
index 0000000..a69e2db
--- /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 113e48a67f00a037b6a70cafdf0a6334be2a5ba7..c342ff2433068a8334e7bc01fd62ac68d2f49543 100644 (file)
--- a/board/mediatek/MAINTAINERS
+++ b/board/mediatek/MAINTAINERS
@@ -1,6 +1,9 @@
 MT8189/MT8371/MT8391 EVK
 M:     Macpaul Lin <macpaul.lin@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