arm64: dts: ti: k3-am62a-wakeup: Configure ti-sysc for wkup_uart0

Similar to the TI K3-AM62x SoC commit ce27f7f
("arm64: dts: ti: k3-am62-wakeup: Configure ti-sysc for wkup_uart0"),
The devices in the wkup domain are capable of waking up the system from
suspend. We can configure the wkup domain devices in a generic way using
the ti-sysc interconnect target module driver like we have done with the
earlier TI SoCs.

As ti-sysc manages the SYSCONFIG related registers independent of the
child hardware device, the wake-up configuration is also set even if
wkup_uart0 is reserved by sysfw.

The wkup_uart0 device has interconnect target module register mapping like
dra7 wkup uart. There is a 1 MB interconnect target range with one uart IP
block in the target module. The power domain and clock affects the whole
interconnect target module.

Note we change the functional clock name to follow the ti-sysc binding
and use "fck" instead of "fclk".

Also note that we need to disable the target module reset as noted by
Markus. Otherwise the sysfw using wkup_uart0 can get confused on some
devices leading to boot time issues such as mbox timeouts.

Signed-off-by: Vibhore Vardhan <[email protected]>
Signed-off-by: Markus Schneider-Pargmann <[email protected]>
[[email protected]: Reworded the entire commit message]
Signed-off-by: Dhruva Gole <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Nishanth Menon <[email protected]>

Author: Vibhore Vardhan

arch/arm64/boot/dts/ti/k3-am62a-wakeup.dtsi

@@ -2,9 +2,11 @@
 /*
  * Device Tree Source for AM62A SoC Family Wakeup Domain peripherals
  *
- * Copyright (C) 2022-2024 Texas Instruments Incorporated - https://www.ti.com/
+ * Copyright (C) 2022-2025 Texas Instruments Incorporated - https://www.ti.com/
  */
 
+#include <dt-bindings/bus/ti-sysc.h>
+
 &cbass_wakeup {
 	wkup_conf: bus@43000000 {
 		compatible = "simple-bus";
@@ -38,14 +40,34 @@
 		};
 	};
 
-	wkup_uart0: serial@2b300000 {
-		compatible = "ti,am64-uart", "ti,am654-uart";
-		reg = <0x00 0x2b300000 0x00 0x100>;
-		interrupts = <GIC_SPI 186 IRQ_TYPE_LEVEL_HIGH>;
+	target-module@2b300050 {
+		compatible = "ti,sysc-omap2", "ti,sysc";
+		reg = <0 0x2b300050 0 0x4>,
+		      <0 0x2b300054 0 0x4>,
+		      <0 0x2b300058 0 0x4>;
+		reg-names = "rev", "sysc", "syss";
+		ti,sysc-mask = <(SYSC_OMAP2_ENAWAKEUP |
+				 SYSC_OMAP2_SOFTRESET |
+				 SYSC_OMAP2_AUTOIDLE)>;
+		ti,sysc-sidle = <SYSC_IDLE_FORCE>,
+				<SYSC_IDLE_NO>,
+				<SYSC_IDLE_SMART>,
+				<SYSC_IDLE_SMART_WKUP>;
+		ti,syss-mask = <1>;
+		ti,no-reset-on-init;
 		power-domains = <&k3_pds 114 TI_SCI_PD_EXCLUSIVE>;
 		clocks = <&k3_clks 114 0>;
-		clock-names = "fclk";
-		status = "disabled";
+		clock-names = "fck";
+		#address-cells = <1>;
+		#size-cells = <1>;
+		ranges = <0 0 0x2b300000 0x100000>;
+
+		wkup_uart0: serial@0 {
+			compatible = "ti,am64-uart", "ti,am654-uart";
+			reg = <0 0x100>;
+			interrupts = <GIC_SPI 186 IRQ_TYPE_LEVEL_HIGH>;
+			status = "disabled";
+	       };
 	};
 
 	wkup_i2c0: i2c@2b200000 {