Hi Chris, > I have a couple of Raspberry Pi 4Bs with a couple of different GPS HATs. > Both GPS HATs work similar - they use the main serial port pins to > transmit the NMEA sentences, several every second once they have GPS > sync. Since u-boot stops on serial input, this keeps them from booting > unattended. This a problem we've sadly had for ever [1], and it's been discussed upstream in U-Boot too (I have tagged messages in my inbox somewhere). There's not yet a good solution, although I was thinking about it the other day. > With a fresh Fedora 41 install, I see u-boot start and then get the EFI > boot menu, which stops until I hit ENTER when the GPS HAT is attached. > > I tried setting bootdelay to -2 but that seems to stop the EFI boot menu > from autobooting no matter what (e.g. pulled the HAT off and it still > stopped there). Why -2? That might be something worth looking into separately. > I also changed stdin/stdout/stderr to remove serial, that didn't seem to > have any effect. No, it doesn't, U-boot very much wants a serial console, there has been a little improvement upstream here though which should be in 2025.01 (I think). > I assume people don't have these problems with the "official" Raspberry > Pi OS - do they build u-boot with different options from Fedora that > allow fully disabling the u-boot serial console mode? They don't use U-Boot, they boot directly from the VC firmware to the kernel using ancient interfaces. This would be solved with the RPi5 as it uses a completely different serial port for the console (and has about 16 serial interfaces on the SoC) but of course that doesn't help with older devices. [1] https://bugzilla.redhat.com/show_bug.cgi?id=1643714 -- _______________________________________________ arm mailing list -- arm@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to arm-leave@xxxxxxxxxxxxxxxxxxxxxxx Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/arm@xxxxxxxxxxxxxxxxxxxxxxx Do not reply to spam, report it: https://pagure.io/fedora-infrastructure/new_issue
