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.
Tested-by: Dhruva Gole <d-gole@ti.com>
Reviewed-by: Kevin Hilman <khilman@baylibre.com>
Tested-by: Markus Schneider-Pargmann <msp@baylibre.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20240213112510.6334-1-tony@atomide.comSigned-off-by: Vignesh Raghavendra <vigneshr@ti.com>

arch/arm64/boot/dts/ti/k3-am62-wakeup.dtsi

@@ -5,6 +5,8 @@
  * Copyright (C) 2020-2024 Texas Instruments Incorporated - https://www.ti.com/
  */
 
+#include <dt-bindings/bus/ti-sysc.h>
+
 &cbass_wakeup {
 	wkup_conf: syscon@43000000 {
 		bootph-all;
@@ -21,15 +23,35 @@ chipid: chipid@14 {
 		};
 	};
 
-	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 = <0x00 0x2b300050 0x00 0x4>,
+		      <0x00 0x2b300054 0x00 0x4>,
+		      <0x00 0x2b300058 0x00 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";
+		clock-names = "fck";
+		#address-cells = <1>;
+		#size-cells = <1>;
+		ranges = <0x0 0x00 0x2b300000 0x100000>;
+
+		wkup_uart0: serial@0 {
+			compatible = "ti,am64-uart", "ti,am654-uart";
+			reg = <0x0 0x100>;
+			interrupts = <GIC_SPI 186 IRQ_TYPE_LEVEL_HIGH>;
 			status = "disabled";
 		};
+	};
 
 	wkup_i2c0: i2c@2b200000 {
 		compatible = "ti,am64-i2c", "ti,omap4-i2c";