From 130d90114c5255a7a729158da8fd8298a02017f1 Mon Sep 17 00:00:00 2001
From: Annette Kobou <annette.kobou@kontron.de>
Date: Mon, 9 Mar 2026 09:57:43 +0100
Subject: arm64: dts: imx8mp-kontron: Fix boot order for PMIC and RTC

The PMIC provides a level-shifter for the I2C lines to the RTC. As the
level shifter needs to be enabled before the RTC can be accessed, make sure
that the PMIC driver is probed first.

As the PMIC also provides the supply voltage for the RTC through the 3.3V
regulator, simply express this in the DT to create the required dependency.

Avoid sporadic boot hangs that occurred when the RTC was accessed before
the level-shifter was enabled.

Fixes: 946ab10e3f40f ("arm64: dts: Add support for Kontron OSM-S i.MX8MP SoM and BL carrier board")
Signed-off-by: Annette Kobou <annette.kobou@kontron.de>
Signed-off-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
 arch/arm64/boot/dts/freescale/imx8mp-kontron-osm-s.dtsi | 6 ++++++
 1 file changed, 6 insertions(+)

--- a/arch/arm64/boot/dts/freescale/imx8mp-kontron-osm-s.dtsi
+++ b/arch/arm64/boot/dts/freescale/imx8mp-kontron-osm-s.dtsi
@@ -330,6 +330,12 @@
 		pinctrl-names = "default";
 		pinctrl-0 = <&pinctrl_rtc>;
 		interrupts-extended = <&gpio3 24 IRQ_TYPE_LEVEL_LOW>;
+		/*
+		 * While specifying the vdd-supply is normally not strictly necessary,
+		 * here it also makes sure that the PMIC driver enables the level-
+		 * shifter for the RTC before the RTC is probed.
+		 */
+		vdd-supply = <&reg_vdd_3v3>;
 	};
 };
 
