Originally Posted by qwertius
I found the following U-Boot port for Galaxy Nexus:
github . com / Ksys-labs / uboot-tuna
But when I try to flash the bootloader via fastboot, the device refuses to accept it because the magic number in the header is different. Makes sense. But according to the docs of Ksys-labs, this bootloader can replace Samsung's stock bootloader and there's even a video on Youtube which claims to demostrate a device booting with this bootloader instead of Samsung's.
How do I make the device (maguro) safely accept the U-Boot bootloader like they did? (I asked them, no respose so far)
You will need an older version of xloader (I think PRIMEKK14 did work) if you want to replace the stock bootloader because that version did not check the bootloader signature. Moreover, you need to edit the file "include/configs/omap4_tuna.h" and uncomment the "#define TUNA_SPL_BUILD" line. Either way, before experimenting, find and download the OMAPFlash for Galaxy Nexus and ensure it works for you.
As for flashing it, I just used "cat /sdcard/bootloader.bin > /dev/...." from Android and "sync". Under /dev/block, you'll find something named like "platform/omap-something/by-name/bootloader".
And take a look at the thread nearby