Raspberry Pi 3 Network Boot

[Greg V]

Hi. I'm looking to boot an RPi3 over the network. Has anyone here done 
that successfully?

I managed to netboot into loader.efi using an updated U-boot (2018.01) 
after doing some terrible hacks in U-boot:

- removing the check that results in EFI_OUT_OF_RESOURCES 
https://github.com/u-boot/u-boot/blob/3dde8f20377c3a051dda64497bdf0cdb23e03a2d/lib/efi_loader/efi_memory.c#L317-L322 
when allocating memory in here: 
https://github.com/freebsd/freebsd/blob/3f5e0fe8f422cbcf092ee1ad453acdb01c560543/stand/efi/loader/copy.c#L202-L203 
— that error never happened with SD card boot though, WTF is going on here?

- changing the receive_filters function 
https://github.com/u-boot/u-boot/blob/3dde8f20377c3a051dda64497bdf0cdb23e03a2d/lib/efi_loader/efi_net.c#L90 
from returning EFI_UNSUPPORTED to EFI_SUCCESS (this probably should 
actually be handled on the loader side?)

But loader.efi could not fetch a kernel to boot. TFTP or NFS, it just 
blinks the ethernet LEDs and errors, no packets are visible on the server…


Also, new U-boot doesn't seem to boot from SD card correctly. Nothing 
happens after the loader (?) displays framebuffer parameters. Has anyone 
else looked into upgrading the U-boot in ports?