We've seen some issues with the x530 under extreme conditions where the DDR gets into a bad state. Generally this results in an application crash, kernel panic then a lock-up in u-boot (generally just as the SPL hands off to u-boot proper).
Enabling the watchdog prevents the lock up and will let the DDR training have another go. Sometimes this recovers but even a reboot loop is better than a complete lockup.
Chris Packham (2): watchdog: orion_wdt: support SPL usage arm: mvebu: x530: Enable watchdog in SPL and U-Boot
arch/arm/dts/armada-385-atl-x530-u-boot.dtsi | 4 ++ board/alliedtelesis/x530/x530.c | 48 ++++++++++++++++++++ configs/x530_defconfig | 5 ++ drivers/watchdog/orion_wdt.c | 4 +- 4 files changed, 58 insertions(+), 3 deletions(-)