[PATCH] ARM: dts: stm32: add reset support to uart nodes on stm32mp15x

[Patrick Delaunay]

STM32 serial IP can be reset via reset controller.
Add the support of reset to uart nodes on stm32mp15-u-boot.dtsi,
the ad-dons file for U-Boot.

This patch fix issues when previous UART configuration, for example
done in TF-A or ROM code, is not handled in U-Boot stm32 serial driver
init.

This reset property won't be not added in Linux kernel device tree
as this reset is not used in Linux STM32 serial driver.

Signed-off-by: Patrick Delaunay <patrick.delaunay at st.com>
---

 arch/arm/dts/stm32mp15-u-boot.dtsi | 32 ++++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/arch/arm/dts/stm32mp15-u-boot.dtsi b/arch/arm/dts/stm32mp15-u-boot.dtsi
index 142ad25c43..c463b49dda 100644
--- a/arch/arm/dts/stm32mp15-u-boot.dtsi
+++ b/arch/arm/dts/stm32mp15-u-boot.dtsi
@@ -179,6 +179,38 @@
 	compatible = "st,stm32-sdmmc2", "arm,pl18x", "arm,primecell";
 };
 
+&usart1 {
+	resets = <&rcc USART1_R>;
+};
+
+&usart2 {
+	resets = <&rcc USART2_R>;
+};
+
+&usart3 {
+	resets = <&rcc USART3_R>;
+};
+
+&uart4 {
+	resets = <&rcc UART4_R>;
+};
+
+&uart5 {
+	resets = <&rcc UART5_R>;
+};
+
+&usart6 {
+	resets = <&rcc USART6_R>;
+};
+
+&uart7 {
+	resets = <&rcc UART7_R>;
+};
+
+&uart8{
+	resets = <&rcc UART8_R>;
+};
+
 &usbotg_hs {
 	compatible = "st,stm32mp1-hsotg", "snps,dwc2";
 };
-- 
2.17.1