Arch Linux

Fauveboy

Member

Registered: 2019-08-03

Posts: 33

booting in BIOS or CSM mode

While installing Arch Im on the following step.

"Verify the boot mode

If UEFI mode is enabled on an UEFI motherboard, Archiso will boot Arch Linux accordingly via systemd-boot. To verify this, list the efivars directory:

# ls /sys/firmware/efi/efivars
If the directory does not exist, the system may be booted in BIOS or CSM mode. Refer to your motherboard's manual for details."

the efivars directory does not exist on the x220t.

I don't know what the instruction means when it says "the system may be booted in BIOS or CSM mode".  Is this saying this is something I need to do or is it saying that its something that is there?....

jasonwryan

Anarchist

From: .nz

Registered: 2009-05-09

Posts: 30,426

Website

Re: booting in BIOS or CSM mode

Read your motherboard's manual, as per the instructions. If you aren't booted in UEFI mode, you can proceed with a standard BIOS install. If your motherboard is capable of UEFI mode, then you should determine why it is not registering. Read this: https://www.happyassassin.net/2014/01/2 … work-then/

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Arch + dwm   •   Mercurial repos  •   Surfraw

Registered Linux User #482438

loqs

Member

Registered: 2014-03-06

Posts: 19,097

Re: booting in BIOS or CSM mode

CSM (Compatibility Support Module) emulates bios functionality on top of EFI while hiding EFI capabilities so can be considered equivalent to BIOS mode.
You would follow steps for installation on a BIOS based system or in the system's firmware search for options that may be preventing EFI boot such as Secure Boot being enabled.
Edit:
beaten by Jason

Last edited by loqs (2019-12-26 18:34:05)

liewkj

Member

Registered: 2019-07-08

Posts: 210

Re: booting in BIOS or CSM mode

While I have never seen such a system myself, some early laptops with InsydeH2O implementation depends on a GPT + EFI System partition on the disk layout to boot in UEFI mode. If the disk layout is blank, with MBR and without EFI system partition, it will boot in Legacy Mode. There may not be user selectable option in the UEFI/BIOS setup utility. I have an old laptop with InsydeH2O implementation but always as UEFI Class 2, ie. It always loads CSM and boots in Legacy Mode.