[PATCH v2] arm: dts: k3-j721e: Fix up MAIN R5FSS cluster mode back to Split-mode

[Suman Anna]

The default U-Boot environment variables and design are all set up for
both the MAIN R5FSS clusters to be in Split-mode. This is the setting
in v2021.01 U-Boot and the dt nodes are synched with the kernel binding
property names in commit 468ec2f3ef8f ("remoteproc: k3_r5: Sync to
upstreamed kernel DT property names") merged in v2021.04-rc2.

The modes for both the clusters got switched back to LockStep mode by
mistake in commit 70e167495ab2 ("arm: dts: k3-j721e: Sync Linux v5.11-rc6
dts into U-Boot") also in v2021.04-rc2. This throws the following warning
messages when early-booting the cores using default env variables,

  k3_r5f_rproc r5f at 5d00000: Invalid op: Trying to start secondary core 7 in lockstep mode
  Load Remote Processor 3 with data at addr=0x82000000 98484 bytes: Failed!
  k3_r5f_rproc r5f at 5f00000: Invalid op: Trying to start secondary core 9 in lockstep mode
  Load Remote Processor 5 with data at addr=0x82000000 98484 bytes: Failed!

Fix this by switching back both the clusters to the expected Split-mode.
Make this mode change in the u-boot specific dtsi file to avoid such
sync overrides in the future until the kernel dts is also switched to
Split-mode by default.

Fixes: 70e167495ab2 ("arm: dts: k3-j721e: Sync Linux v5.11-rc6 dts into U-Boot")
Reported-by: Minas Hambardzumyan <minas at ti.com>
Signed-off-by: Suman Anna <s-anna at ti.com>
---
v2:
 - Move the cluster mode change from k3-j721e-main.dtsi to the u-boot
   board dtsi file, k3-j721e-common-proc-board-u-boot.dtsi
 - Update commit description citing the reason
v1:
http://patchwork.ozlabs.org/project/uboot/patch/20210514003603.13940-1-s-anna@ti.com/

 arch/arm/dts/k3-j721e-common-proc-board-u-boot.dtsi | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/arch/arm/dts/k3-j721e-common-proc-board-u-boot.dtsi b/arch/arm/dts/k3-j721e-common-proc-board-u-boot.dtsi
index 3384ed9f3a1e..fe095a6153ed 100644
--- a/arch/arm/dts/k3-j721e-common-proc-board-u-boot.dtsi
+++ b/arch/arm/dts/k3-j721e-common-proc-board-u-boot.dtsi
@@ -193,3 +193,11 @@
 &mcu_fss0_ospi1_pins_default {
 	u-boot,dm-spl;
 };
+
+&main_r5fss0 {
+	ti,cluster-mode = <0>;
+};
+
+&main_r5fss1 {
+	ti,cluster-mode = <0>;
+};
-- 
2.30.1