Hi Gijs, On Wed, 25 Dec 2024 at 02:59, Gijs Peskens <gijs.pesk...@munisense.com> wrote: > > I'm working on getting a compute module working with Yocto using U-Boot > as bootloader, which mostly works thanks to previous work to get RPi 5 > working. > However I'm running into a strange issue: if I turn on the CM5 without > the debug UART (which requires soldering a header onto the CM5) > attached, the Pi doesn't boot beyond showing the submarine splash > screen, if I boot it with the console attached it autoboots correctly. > If I attach the UART after the boot halted and press enter I get a > U-Boot console, and giving the boot command boots it normally. > And setting bootdelay=-2 in the env allows it to correctly boot. > > Which leads me to believe there is perhaps a spurious input registered > by U-Boot which interrupts autobooting. > > Is there a command that allows me to extract why U-Boot didn't continue > autobooting? > > And anyone have a hint how this could perhaps be fixed in a more elegant > way (allowing interruptable autoboot). > > The hardware I'm testing on is the CM5 devkit, I needed to make small > changes to yocto to get it working: > https://github.com/agherzan/meta-raspberrypi/pull/1397 > > No changes were needed in U-Boot to get it to boot >
I see the same thing. I wonder if we need to be able to silently disable the UART. I made a few attempts at [1] and [2]. Tom specifically mentioned the rpi at [3]. At least for the case where I saw it in my lab, the board continued to boot OK, even though no console output appeared on the display. I haven't actually made time to investigate this though. Regards, Simon [1] https://patchwork.ozlabs.org/project/uboot/patch/20231101180447.99361-1-...@chromium.org/ [2] https://patchwork.ozlabs.org/project/uboot/list/?series=433605 [3] https://patchwork.ozlabs.org/project/uboot/cover/20241120153554.860710-1-...@chromium.org/
