Does not reboot after WDOG reset.

[bamkrs]

If the linux watchdog /etc/watchdog is used and the WDOG triggers an reset, uboot stops after unpacking the kernel - where it should load the DTB - and prints:

ERROR: Did not find a cmdline Flattened Device Tree

After powercycling, the device/uboot boots just fine.

[lw-karo]

Moin moin,

If the linux watchdog `/etc/watchdog` is used and the WDOG triggers an reset, uboot stops after unpacking the kernel - where it should load the DTB - and prints: ``` ERROR: Did not find a cmdline Flattened Device Tree ``` After powercycling, the device/uboot boots just fine.

see: U-Boot/sources/TX*/README: |The following variables are automatically created by U-Boot under |certain circumstances (these are unset otherwise and won't be created |from the saved environment upon boot): | |safeboot=1 signifies, that <CTRL-C> has been detected early during | boot and the above noted safety measures have been | taken. | |wdreset=1 signifies, that the module has been booted due to a | watchdog reset. This can be used to change the booting | behaviour depending on the reset source. | | You can use these variables in boot scripts e.g. to | select a fallback boot script when a watchdog reset | occured: |setenv bootcmd 'run run bootcmd_${boot_mode}${wdreset} bootm_cmd' |With the default setting of 'boot_mode=nand' this will run either the |commands stored in 'bootcmd_nand' if no watchdog reset happened or |'bootcmd_nand1' when a watchdog reset was detected. | |Note: If a watchdog reset occured, a soft reset should be performed |before booting the actual OS, to make sure that the board is correctly |configured (PMIC, cpu_clk, splash image). Lothar Waßmann --

…

___________________________________________________________ Ka-Ro electronics GmbH | Pascalstraße 22 | D - 52076 Aachen Phone: +49 2408 1402-0 | Fax: +49 2408 1402-10 Geschäftsführer: Matthias Kaussen Handelsregistereintrag: Amtsgericht Aachen, HRB 4996 www.karo-electronics.de | [email protected]

___________________________________________________________

[dargo600]

I have had seen this issue as well on the Sept 18th 2020 release of uboot for tx6 specifically the TX6U-8030 hardware. The reproduce scenario was have watchdog enabled in the kernel but with no daemon running. Then sudo touch /dev/watchdog0.

I would sometimes observe that it repeatedly attempts to reboot more than 3 times and then switches to the rescue partition. Sometimes it reboots so frequently and change the reboot cause from WDOG to POR. Though this doesn't always happen. I think when that happens the wdreset=1 uenv variable will no longer be set.
bootcount will either be 3 or 4 because it reboots so many times after failing to find the flattened device tree.