Re: watchdog timeout on Wandboard Quad

Dmitry Salychev <[email protected]> writes:

> 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

For example,

src/sys/contrib/device-tree/src/arm/nxp/imx/imx6qdl.dtsi

has

			wdog1: watchdog@20bc000 {
				compatible = "fsl,imx6q-wdt", "fsl,imx21-wdt";
				reg = <0x020bc000 0x4000>;
				interrupts = <0 80 IRQ_TYPE_LEVEL_HIGH>;
				clocks = <&clks IMX6QDL_CLK_IPG>;
			};

			wdog2: watchdog@20c0000 {
				compatible = "fsl,imx6q-wdt", "fsl,imx21-wdt";
				reg = <0x020c0000 0x4000>;
				interrupts = <0 81 IRQ_TYPE_LEVEL_HIGH>;
				clocks = <&clks IMX6QDL_CLK_IPG>;
				status = "disabled";
			};

Regards,
Dmitry

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

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