dts: arm: renesas: ra: Add battery backup node for Renesas

RA8 family

Add a battery backup (VBAT) node to the device tree for the Renesas
RA8 family. This enables support for RTC VBAT domain switching when main
power is lost.

Signed-off-by: Khoa Tran <[email protected]>

Author: khoatranyj

dts/arm/renesas/ra/ra8/r7fa8t1xh.dtsi

@@ -10,6 +10,7 @@
 
 /delete-node/ &i2s0;
 /delete-node/ &i2s1;
+/delete-node/ &battery_backup;
 
 / {
 	clocks: clocks {

dts/arm/renesas/ra/ra8/ra8x1.dtsi

@@ -57,7 +57,29 @@
 		system: system@4001e000 {
 			compatible = "renesas,ra-system";
 			reg = <0x4001e000 0x1000>;
+			#address-cells = <1>;
+			#size-cells = <1>;
 			status = "okay";
+
+			battery_backup: battery-backup@3b0{
+				compatible = "renesas,ra-battery-backup";
+				reg = <0x3b0 0x2>, <0x3d0 0x4>,
+				      <0xa84 0x1>, <0xa88 0x1>,
+				      <0xc40 0x1>, <0xc45 0x1>,
+				      <0xc46 0x1>, <0xc48 0x1>,
+				      <0xc49 0x1>, <0xc4a 0x1>,
+				      <0xc4c 0x1>, <0xc4d 0x1>,
+				      <0xc4e 0x1>, <0xd00 0x80>;
+				reg-names = "vbrsabar", "bbfsar",
+					    "vbattmnselr", "vbtbpcr1",
+					    "vbtber", "vbtbpcr2",
+					    "vbtbpsr", "vbtadsr",
+					    "vbtadcr1", "vbtadcr2",
+					    "vbtictlr", "vbtictlr2",
+					    "vbtimonr" , "vbtbkrn";
+				manual-configure;
+				status = "disabled";
+			};
 		};
 
 		elc: elc@40201000 {

dts/arm/renesas/ra/ra8/ra8x2.dtsi

@@ -69,7 +69,29 @@
 		system: system@4001e000 {
 			compatible = "renesas,ra-system";
 			reg = <0x4001e000 0x1000>;
+			#address-cells = <1>;
+			#size-cells = <1>;
 			status = "okay";
+
+			battery_backup: battery-backup@3b0{
+				compatible = "renesas,ra-battery-backup";
+				reg = <0x3b0 0x2>, <0x3d0 0x4>,
+				      <0xa84 0x1>, <0xa88 0x1>,
+				      <0xc40 0x1>, <0xc45 0x1>,
+				      <0xc46 0x1>, <0xc48 0x1>,
+				      <0xc49 0x1>, <0xc4a 0x1>,
+				      <0xc4c 0x1>, <0xc4d 0x1>,
+				      <0xc4e 0x1>, <0xd00 0x80>;
+				reg-names = "vbrsabar", "bbfsar",
+					    "vbattmnselr", "vbtbpcr1",
+					    "vbtber", "vbtbpcr2",
+					    "vbtbpsr", "vbtadsr",
+					    "vbtadcr1", "vbtadcr2",
+					    "vbtictlr", "vbtictlr2",
+					    "vbtimonr" , "vbtbkrn";
+				manual-configure;
+				status = "disabled";
+			};
 		};
 
 		pinctrl: pin-controller@40400800 {