Hi all,
I have successfully gotten a Raspberry Pi 4 booting over the network with the 32-bit version of Arch Linux ARM, however after experiencing some issues (no USB support due to host controller drivers failing with an error, hardware accelerated decoding not working due to missing /dev/vchiq) I am trying to give the 64-bit version a go to see if it supports the Pi4 hardware a bit better.
However for some reason the 64-bit version no longer seems to boot the kernel directly, instead launching U-Boot. This means that I only get as far as U-Boot loading over the network, but then it complains that it can't find any kernel files.
It tries to download a file called "pxelinux.cfg/default" from the TFTP server so I put a KERNEL and APPEND command in there and U-Boot picks this up, downloads the initramfs-linux.img file but then complains that "kernel_comp_addr_r or kernel_comp_size is not provided". It then tries to download "boot.scr.uimg" which isn't included in the original files, just "boot.scr" which has references to the SD card so doesn't seem relevant to my network booting process.
So at this point I'm a bit lost as I'm not sure what sort of memory addresses I'm supposed to pass or how to get the device tree overlay files specified since the included "boot.scr" seems to refer to them.
Are there any instructions or a guide on how to get the 64-bit Arch Linux ARM U-Boot to boot a Pi4 over the network? I presume it would be relatively standard U-Boot commands but the kernel addresses and device tree stuff seems to be Pi specific and has me a bit stumped.