legacy BIOS programs were in ROM in the PC. and UEFI is being more used than BIOS.
Where is the UEFI code(compiled binary form) kept?
And are the UEFI drivers provided now by the OS?
I would deeply appreciate it if someone could give me a brief explanation of bootstrap using UEFI.
This is an update after a year with some knowledge I got to know since I posted this question. I understand UEFI firmware is kept in EEPROM(these days they keep it in EEPROM because upgrade is possible in place) or flash memory(I guess they use NAND flash-block device, should be first loaded to RAM, or NOR flash - random access possible, can be directly executed)
When I examine /boot/efi directory which is the ESP(EFI system partition), I see
ubuntu directory under /boot/efi/EFI. In both directories, there are some .efi files and using
file command I can see those are binary executables for PE32 virtual machine(EFI firmwares use this PE32 machine code which is independent of CPU architecture or ISA). So many firmwares are now also in ESP. I understand there some tables (in ESP I guess) for connecting the firmware service with OS runtime or boottime.