Sysupgrade fails when kernel console is disabled
Username: Koen Vandeputte
Origin: https://bugs.openwrt.org/index.php?do=details&task_id=1071
Hardware used:
- Gateworks Ventana imx6 board (GW5200)
Synopsis:
Running sysupgrade with a valid image fails if the kernel console is disabled in u-boot (setenv console ; saveenv; reset)
As soon as sysupgrade starts, the board reboots immediately.
The detected reboot reason displayed is exactly the same in both cases.
Reset cause: WDOG
WDOG1 Reset cause: SFTW
WDOG2 Reset cause: POR
Basically:
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Kernel console enabled (console = ttymxc1) –> sysupgrade runs normally and succeeds
-
Kernel console disabled (console = ) –> The board reboots within 1 second as soon as sysupgrade starts
Rationale for disabling kernel console:
-
This board exposes 2 UART ports for user applications (ttymxc0, ttymxc1)
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ttymxc1 is shared with the kernel console and needs to be disabled so it does not interfere with the peripheral communication
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Both ports are used in my case (ttymxc0: GPS received ; ttymxc1: Iridium modem)