ARM: dts: stm32: Add arm,no-tick-in-suspend to STM32MP15xx STGEN timer

STM32MP15xx RM0436 Rev 6 section 46.3 System timer generator (STGEN) states
"
Arm recommends that the system counter is in an always-on power domain.
This is not supported in the current implementation, therefore STGEN should
be saved and restored before Standby mode entry, and restored at Standby
exit by secure software.
...
"
Instead of piling up workarounds in the firmware which is difficult to
update, add "arm,no-tick-in-suspend" DT property into the timer node to
indicate the timer is stopped in suspend, and let the kernel fix the
timer up.

Fixes: 8471a20253eb ("ARM: dts: stm32: add stm32mp157c initial support")
Signed-off-by: Marek Vasut <marex@denx.de>
Signed-off-by: Alexandre Torgue <alexandre.torgue@foss.st.com>

diff --git a/arch/arm/boot/dts/st/stm32mp151.dtsi b/arch/arm/boot/dts/st/stm32mp151.dtsi
index 90c5c72c87ab7e7c7ac74b297922f080cb5ab7c1..4f878ec102c1f681577fe19d766d9dbf4bce1988 100644 (file)
--- a/arch/arm/boot/dts/st/stm32mp151.dtsi
+++ b/arch/arm/boot/dts/st/stm32mp151.dtsi
@@ -50,6 +50,7 @@
                             <GIC_PPI 11 (GIC_CPU_MASK_SIMPLE(1) | IRQ_TYPE_LEVEL_LOW)>,
                             <GIC_PPI 10 (GIC_CPU_MASK_SIMPLE(1) | IRQ_TYPE_LEVEL_LOW)>;
                interrupt-parent = <&intc>;
+               arm,no-tick-in-suspend;
        };
 
        clocks {