Hi, I observed strange behaviour on our custom carrier board and colibri imx7.
On our system, if one brings down the interface with ifconfig eth0 down, the system freezes after about 5 seconds with some boards: E.g. I don’t see it with colibri imx7d number 03115176 but with number 03139590.
There are some cases where this behaviour can’t be seen:
If one is fast enough with putting ifconfig eth0 up, everything is fine
Unfortunately I could not reproduce the behaviour on the colibri eval board (with a colibri which causes problems on our carrier board), it seems that there is a hardware issue on our side
I do not observe this behavour if lcdif is “okay” in the devicetree
My workaround for now is to enable lcdif in the devicetree even if we do not use any display and comment out the pins in pincontrols for lcdif (as we use some of them as flextimer or gpio)
Do you have any idea what could cause this strange behaviour on our carrier board? E.g. is there any difference on the colibris which I mentioned, which could give us a hint?
I get the following messages (after ifconfig eth0 down and before system freeze):
Mar 5 13:07:10 DTS480x user.debug kernel: [ 1068.328951]
Mar 5 13:07:10 DTS480x user.debug kernel: [ 1068.328951] Bus freq set to 24000000 start...
Mar 5 13:07:10 DTS480x user.debug kernel: [ 1068.329235] Bus freq set to 24000000 done! cpu=0
Mar 5 13:07:10 DTS480x user.debug kernel: [ 1068.351260]
Mar 5 13:07:10 DTS480x user.debug kernel: [ 1068.351260] Bus freq set to 533000000 start...
Mar 5 13:07:10 DTS480x user.debug kernel: [ 1068.351993] Bus freq set to 533000000 done! cpu=0
I’m not sure if I understand your first question correctly… What I changed to get a working software for my custom carrier board was to set the status property of lcdif to “okay” in the devicetree. Somehow it has an effect if the lcd driver gets started or not… It doesn’t sound logical at all, but I can reproduce it.
I hope this answer is somehow what you expected, otherwise please tell me.
Could you update to Bsp 2.8b5 and check if you still have this Issue?
I think the issue could be related to the pins which are used by lcdif on your custom board. You could measure the output (voltage) of these pins in working and non working conditions. You may also export some of these pins and check if the issue is related to one of these pins.
