Booting an x86-64 BIOS Machine

[Desone Burns]

Hello,

I have an application in which I need to boot an x86-64 machine with a
legacy BIOS. I've read about the U-Boot executable, the SPL, and the
TPL. I'm just having a bit of trouble figuring out which pieces are
supposed to go where. Looking to Grub, I see there exists a minimal
"boot.img" file, which gets installed into the MBR of the drive and
subsequently bootstraps the rest of the sequence. My impression was
that either the TPL or the SPL would play that same role, but even
removing basically all options, the binary produced is still too large
to fit in this 512 Byte area. Syslinux also works on my device, and
the "mbr.bin" and "gptmbr.bin" files play the same role for that
bootloader. How can I make optimizations to generate an image small
enough to fit into the MBR of my device to allow BIOS to load the rest
of the bootloader?

-- 
Desone Burns II
Software Engineer III
seegrid.com  •  412-379-4500
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