A tiny subset of UEFI would be nice (ability to load files from a fat32/exfat/something partition, framebuffer, memory map). Also a subset of ACPI (enumeration of PCI devices) and XHCI (enumeration of USB devices). That's enough of a starting point where you can load drivers, and show the user an error if there's unknown hardware.
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A tiny subset of UEFI would be nice (ability to load files from a fat32/exfat/something partition, framebuffer, memory map). Also a subset of ACPI (enumeration of PCI devices) and XHCI (enumeration of USB devices). That's enough of a starting point where you can load drivers, and show the user an error if there's unknown hardware.