arm64: dts: st: use lptimer3 as tick broadcast source on stm32mp257f-ev1

During the low power modes the generic ARM timer is deactivated, so the
the tick broadcast is used, based on LPTIMER3 which is clocked by LSE on
STMicroelectronics boards.

Signed-off-by: Patrick Delaunay <[email protected]>
Signed-off-by: Fabrice Gasnier <[email protected]>
Signed-off-by: Alexandre Torgue <[email protected]>

Author: Fabrice Gasnier

arch/arm64/boot/dts/st/stm32mp257f-ev1.dts

@@ -222,6 +222,14 @@
 	};
 };
 
+/* use LPTIMER with tick broadcast for suspend mode */
+&lptimer3 {
+	status = "okay";
+	timer {
+		status = "okay";
+	};
+};
+
 &rtc {
 	status = "okay";
 };