Re: watchdog timeout on Wandboard Quad

Michael Tuexen <[email protected]> writes:

>> On 20. May 2026, at 17:38, Rodney W. Grimes <[email protected]> wrote:
>> 
>>> Dear all,
>>> 
>>> I want to run FreeBSD current on a Wandboard Quad. I installed
>>> https://download.freebsd.org/snapshots/arm/armv7/ISO-IMAGES/16.0/FreeBSD-16.0-CURRENT-arm-armv7-GENERICSD-20260518-ca67cfa5237f-285947.img.xz
>>> on a SD card and also installed /usr/local/share/u-boot/u-boot-wandboard/u-boot.imx as described
>>> in /usr/local/share/u-boot/u-boot-wandboard/README
>>> 
>>> FreeBSD boots fine but every two minutes the watchdog timer fire and uboot boots again.
>>> 
>>> The message is:
>>> 
>>> U-Boot SPL 2025.10 (May 03 2026 - 12:17:39 +0000)
>>> Trying to boot from MMC1
>>> 
>>> 
>>> U-Boot 2025.10 (May 03 2026 - 12:17:39 +0000)
>>> 
>>> CPU:   Freescale i.MX6Q rev1.2 at 792 MHz
>>> Reset cause: WDOG
>>> DRAM:  2 GiB
>>> Core:  65 devices, 19 uclasses, devicetree: separate
>>> WDT:   Started watchdog@20bc000 with servicing every 1000ms (128s timeout)
>>> MMC:   FSL_SDHC: 4, FSL_SDHC: 1, FSL_SDHC: 0
>>> Loading Environment from MMC... Reading from MMC(0)... *** Warning - bad CRC, using default environment
>>> 
>>> i2c_mxc i2c@21a4000: i2c bus 1 at 0x21a4000, fail to request scl/sda gpio
>>> auto-detected panel FWBADAPT-LCD-F07A-0102
>>> Display: FWBADAPT-LCD-F07A-0102 (800x480)
>>> In:    serial
>>> Out:   serial
>>> Err:   serial
>>> Board: Wandboard rev C1
>>> Net:   eth0: ethernet@2188000
>>> 
>>> Hit any key to stop autoboot: 0
>>> 
>>> How can I avoid this periodic reboot?
>>> 
>> 
>> Best way would be to find out how to disable the WDT:  Started you show above,
>> but I am not sure how to do that.
>> 
>> So.....
>> watchdog -t 0
>> should disable it, put this in /etc/rc.local, hopefully that gits run before the 128 seconds.
> I can log in after boot as root (for a short time ) and get
>
> root@generic:~ # watchdog -t 0
> watchdog: patting the dog: Operation not supported
> root@generic:~ # 
>
> Then the machine reboots...

I'm thinking loudly, but you'd try to look at the device tree, find this
watchdog and disable it with an overlay. I've a couple of links with DTS
manipulation (but for BBB, not Wandboard):

https://www.bidouilliste.com/blog/2015/11/28/Porting-FreeBSD-to-a-new-ARM-Board-Part-2/
https://www.righto.com/2016/08/pru-tips-understanding-beaglebones.html

Regards,
Dmitry

>
> Best regards
> Michael
>> 
>>> Best regards
>>> Michael
>> 
>> -- 
>> Rod Grimes                                                 [email protected]

-- 
https://wiki.freebsd.org/DmitrySalychev