firmware is a pretty common term for things like this (code on chip that manages low level startup)

It’s still a stupid term no matter how common it is. It has little to nothing to do with firms.

Linux Distro from Scratch, LDS. 😜

No, mormon.

We pray for pacman to deliver as he often does.

All hail to pacman!

Oh wait, I see that vmlinuz file has a version to it. I couldn’t remember if vmlinuz was the kernel or not, because I used to have multiples of them, but these days I only have one.

GRUB gets installed on your harddisk in your root partition, it’s configuration file on the boot partition and finally into your boot sector if I’m correct. UEFI is a standard for your firmware located outside your harddisk. You go from firmware -> partition layout -> bootloader (grub) -> kernel.

The firmware is closed source under BIOS or UEFI or if you’re hardcore open source, libreboot/coreboot/‘other options’ and is located somewhere on your motherboard on some chip.
Then there’s the partition layout and bootloader that are located inside /dev/sda I believe, so inside the device itself, which can be read if you want to take a peek at it.

Now the bootloader located in the boot sector /dev/sda loaded by the firmware located in some chip in the motherboard, has access to the boot partition, where it loads the bootloader’s configuration file usually located at /boot/grub/grub.cfg for GRUB. I remember UEFI having some kind of standard bootloader by itself, so it doesn’t even need a bootloader if I can remember correctly.

This what I recall as it was quite complicated for me too. Especially with software being called firmware and not being called motherbootware or pre-bootware or anything that indicates that this piece of software is the very first thing that starts running during boot.

But you look at /boot and what you can find there. There will be at least two files there called initramfs and vmlinuz, which were also part of the boot process, but I forgot what role those two played.