Multiboot2 magic number

I could use some help getting RTEMS-6.2 booting with GRUB.

When booting with:
qemu-system-x86_64 -m 512 -serial stdio --bios $OVMF_LOCATION -drive format=raw,file=rtems-qemu.img

I see the following errors:
error: no multiboot header found.
error: you need to load the kernel first.

When attempting to boot the elf file directly like this:
qemu-system-x86_64 -kernel rtems-epics-cr12 -nographic -serial mon:stdio

I see the following error:
qemu-system-x86_64: Error loading uncompressed kernel without PVH ELF Note

A search for the multiboot2 magic number(0xE85250D6) in the ELF file returns no results. Any thoughts on how to resolve this?