Watchdog reset on imx6ul

[pietercardoen]

Dear

I am facing troubles with the watchdog on imx6ul. I am using u-boot 2016.03.

I configure:

* the WCR register to 0xFF34 (WDT and WDE enabled and timeout 128s)

* the WMCR register to 0x0000 (Power down counter disabled)

* the WSR to 0x5555 and afterwards to 0xaaaa

After 12 seconds, the board reboots and reset cause is WDOG.

If I change the timeout to 60 seconds, nothing changes. Also after 12 seconds, the board reboots.

What could cause this strange behaviour?

Best regards

Pieter

[igorpadykov]

Hi Pieter

reason may be that wdog was already initialized before, for example

in iROM by fuses, note that some wdog fields are write-once only.

Best regards
igor
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[pietercardoen]

Igor

The issue was that the 32kHz clock was missing and apparently, the i.MX6UL behaved unpredictably. By adding this component, the WDOG behaves normal.

Best regards

Pieter Cardoen