Several TI K3 SoCs like J7200, J721E, J721S2, J784S4 and J742S2 have a
R5F cluster in the MCU domain which is configured for LockStep mode at
the moment. The necessary support to use MCU R5F cluster in split mode
has been added in the bootloader. And the TI IPC firmware for the split
processors is already available public.

Now that the firmware dependent configs have been isolated out from
board level DTS to the TI IPC Firmware DTSI since
commit c5b645dbecd6 ("arm64: dts: ti: k3-j7200-ti-ipc-firmware: Refactor
IPC cfg into new dtsi"), switch this R5F cluster to Split mode by
default in all the boards using TI IPC Firmware config. This gives out
an extra general purpose R5F core free to run any applications as
required. Lockstep mode remains default in the SoC level dtsi, so
downstream board dts which do not use TI IPC Firmware config should not
be impacted by this switch.

Users who prefer to use the fault-tolerant lockstep mode with TI IPC
firmware config, can do that by setting `ti,cluster-mode` property to 1.

Signed-off-by: Beleswar Padhi <b-padhi@ti.com>
---
v2: Changelog:
[Andrew]:
 1. Posted this as a separate patch from the DT refactoring series[0]
[General]:
 2. Updated commit message to indicate the refactoring series has been
    merged, and now its time to switch the R5 Clusters into Split mode
    in the TI IPC Firmware config.

Link to v1:
https://lore.kernel.org/all/20250814223839.3256046-34-b-padhi@ti.com/

Testing Done:
1. Tested that this patch does not introduce any new warnings/errors.
2. Tested Split core functionality of MCU R5F Cluster in TI J784S4 EVM.

[0]: https://lore.kernel.org/all/32d4b3c2-4017-4ad2-8527-493b6d3b7ecb@ti.com

 arch/arm64/boot/dts/ti/k3-j7200-ti-ipc-firmware.dtsi             | 1 +
 arch/arm64/boot/dts/ti/k3-j721e-ti-ipc-firmware.dtsi             | 1 +
 arch/arm64/boot/dts/ti/k3-j721s2-ti-ipc-firmware.dtsi            | 1 +
 .../boot/dts/ti/k3-j784s4-j742s2-ti-ipc-firmware-common.dtsi     | 1 +
 4 files changed, 4 insertions(+)

diff --git a/arch/arm64/boot/dts/ti/k3-j7200-ti-ipc-firmware.dtsi b/arch/arm64/boot/dts/ti/k3-j7200-ti-ipc-firmware.dtsi
index 9477f1efbbc61..b66faa2543f71 100644
--- a/arch/arm64/boot/dts/ti/k3-j7200-ti-ipc-firmware.dtsi
+++ b/arch/arm64/boot/dts/ti/k3-j7200-ti-ipc-firmware.dtsi
@@ -94,6 +94,7 @@ &main_timer2 {
 
 &mcu_r5fss0 {
 	status = "okay";
+	ti,cluster-mode = <0>;
 };
 
 &mcu_r5fss0_core0 {
diff --git a/arch/arm64/boot/dts/ti/k3-j721e-ti-ipc-firmware.dtsi b/arch/arm64/boot/dts/ti/k3-j721e-ti-ipc-firmware.dtsi
index 40c6cc99c4056..abd0d137d860d 100644
--- a/arch/arm64/boot/dts/ti/k3-j721e-ti-ipc-firmware.dtsi
+++ b/arch/arm64/boot/dts/ti/k3-j721e-ti-ipc-firmware.dtsi
@@ -211,6 +211,7 @@ &main_timer15 {
 };
 
 &mcu_r5fss0 {
+	ti,cluster-mode = <0>;
 	status = "okay";
 };
 
diff --git a/arch/arm64/boot/dts/ti/k3-j721s2-ti-ipc-firmware.dtsi b/arch/arm64/boot/dts/ti/k3-j721s2-ti-ipc-firmware.dtsi
index ebab0cc580bbb..54ae8c86901ec 100644
--- a/arch/arm64/boot/dts/ti/k3-j721s2-ti-ipc-firmware.dtsi
+++ b/arch/arm64/boot/dts/ti/k3-j721s2-ti-ipc-firmware.dtsi
@@ -183,6 +183,7 @@ &main_timer5 {
 };
 
 &mcu_r5fss0 {
+	ti,cluster-mode = <0>;
 	status = "okay";
 };
 
diff --git a/arch/arm64/boot/dts/ti/k3-j784s4-j742s2-ti-ipc-firmware-common.dtsi b/arch/arm64/boot/dts/ti/k3-j784s4-j742s2-ti-ipc-firmware-common.dtsi
index 455397227d4a1..ff9a296b927a8 100644
--- a/arch/arm64/boot/dts/ti/k3-j784s4-j742s2-ti-ipc-firmware-common.dtsi
+++ b/arch/arm64/boot/dts/ti/k3-j784s4-j742s2-ti-ipc-firmware-common.dtsi
@@ -254,6 +254,7 @@ &main_timer9 {
 };
 
 &mcu_r5fss0 {
+	ti,cluster-mode = <0>;
 	status = "okay";
 };
 
-- 
2.34.1