I encounter a weird problem with my custom imx6ul board.
The system boot normally (we are using Buildroot based solution) but hangs EXACTLY in 600 seconds after the OS takes its control.
U-Boot does not have such behaviour, it lasts until reset or power off.
I tried to rebuild Linux kernel in different ways, clocks, idle, power modes but there is no effect on it.
Don't think it's a kind of HW issues, all power rails looks stable, clocks are preset.