Hello,
I had strange problem reproducible 100% on HP t640 (AMD Ryzen) when booting from usb pendrive - squashfs\efi image.
When kernel has configured "console=ttyS0" in grub it doesn't boot.
The same pendrive boot Intel based laptop to openwrt console.
Similar problem mentioned here (Post #11)
Is there anything that could be done about that in Openwrt?
If there is no serial port hardware available to the system, you may need to disable serial in the GRUB configuration.
First check your BIOS configuration to be sure that at least one serial port (if present in the motherboard chipset) is enabled. It does not need to be actually connected.
No, there is no serial port.
The default configuration that fails the boot looks like a bug to me. It is quite unobvious behaviour.
So remove the console/serial params?
Yes, removing params works.
So far, most PCs had a serial port -somehow-, it usually hasn't been brought out to the outside for the last two decades, but it was there, be it as a header on the board (without the bracket to the outside) or not even that, just part of the southbridge's LPC bus. We're slowly starting to see mainboards that really don't have serial anymore, but that's a relatively new thing.
HP t640 is not so new hardware - 2020.
It has optional double serial addon over HP proprietary port.
But the question is how to save time for users that came problem.
I can see 2 solutions:
document it by adding small note (maybe I just missed something that already in wiki)
or it is possible to configure openwrt to ignore nonexistent serial.
While the note seems to be something I can handle, for the 2nd option I will need guidance.
Thanks.