Pinging to report that I have a similar issue.
Ran pacman -Syu && reboot yesterterday and my pi 3B+ didn't come back online. The ACT LED blinked a pattern of two short pulses and a long pause for 6 times and the device didn't appear on the network.
The dtb files were dated Jan 27, 2020 and the kernel version was linux-aarch64-5.16.3-1.
Trying o boot with HDMI, no dice: black screen and the same blinking pattern. I just copied over the /boot directory from a fresh ArchLinuxARM-rpi-aarch64-latest.tar.gz file and managed to boot the pi to the console, but the only network device available was
lo. At boot, I got a message like
$this->bbcode_second_pass_code('', '
Net: no ethernet found
')
Booting the SD card in qemu and updating raspberrypi-bootloader to version 20220202 just made the HDMI output go black after a few seconds booting (even with hdmi_safe=1 in config.txt).
$this->bbcode_second_pass_quote('lategoodbye', '@')mmoya Thanks a lot. This shows me that the mainline kernel is running with the downstream device tree. This isn't reliable as already said in
viewtopic.php?f=65&t=15791This isn't a kernel regression, it was just luck that it worked until now. The Arch Linux distribution must be fixed instead. Sorry, i cannot help here.
I just booted the SDcard again in qemu and replaced linux-aarch64 with linux-rpi as suggested and was