UEFI Install Guide

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Revision as of 01:50, 16 January 2014 by 24.181.212.141 (Talk)

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This tutorial will show you how to install Funtoo on a UEFI system. UEFI, also known as the Unified Extensible Firmware Interface, is a new firmware interface that is used on some newer computers as a replacement for the traditional PC BIOS. It has an integrated boot loader, so setting up booting is different.

This tutorial is meant to be an "overlay" over the Regular Funtoo Installation. Follow the normal installation and only follow steps in this tutorial when dealing with partitioning and configuring the boot loader (GRUB). All steps are otherwise identical to the regular installation process.

Contents

What Are We Doing?

This guide will show you how to set up your UEFI system to load the GRUB boot loader, which will then load your Funtoo Linux kernel and initramfs. This is the "UEFI + GRUB" method as described on the Boot Methods page.

First Steps

To install Funtoo Linux on a UEFI system, first you need to boot SysRescueCD in UEFI mode. To do this, enable UEFI in your BIOS, and if necessary disable legacy booting. After some fiddling, you should be able to boot SysRescueCD and get a black and white text menu instead of the traditional aqua/cyan-colored menu. The black and white menu indicates that you booted SysRescueCD in UEFI mode. Once you've accomplished this, you're ready to continue with your Funtoo Linux installation and partition your drive. See below for details.

If the /sys/firmware/efi directory exists, then you have successfully booted in EFI mode and will be able to configure your Funtoo system to boot in EFI mode. If the directory doesn't exist, fix this first. It is a requirement for setting up EFI booting.

Partitioning

To set up your partitions for UEFI booting, you will create a ~500MB FAT32 partition on /dev/sda1, and set it to type EF00 using gdisk.

Command: n ↵
Partition Number: 1 ↵
First sector: 
Last sector: +500M ↵
Hex Code: EF00

This partition will serve as your Funtoo /boot filesystem as well as the partition that the UEFI firmware can read to load GRUB. Then you will set up swap on /dev/sda2 and your root filesystem on /dev/sda3. To create the FAT32 filesystem, type:

# mkfs.vfat -F 32 /dev/sda1

Your /etc/fstab entry for this filesystem will also differ, and will look like this:

/dev/sda1		/boot		vfat		noatime	1 2

Make sure you add VFAT support to your kernel if you are building it manually.

Boot Loader

Emerging GRUB

You will still use GRUB as a boot loader, but before emerging grub, you will need to enable EFI booting. To do this, add the following line to /etc/portage/make.conf:

GRUB_PLATFORMS="efi-64"

Then, emerge grub. You will notice efibootmgr getting pulled in as a dependency. This is expected and good.

Installing GRUB

Now, for the magic of getting everything in place for booting. You should copy your kernel and initramfs (if you have one -- you will if you are following the default install) to /boot. GRUB will boot those. But how do we get UEFI to boot GRUB? Well, we need to run the following command:

# grub-install --target=x86_64-efi --efi-directory=/boot /dev/sda

This command will simply install all the stuff to /boot/EFI and /boot/grub that your system needs to boot. In particular, the /boot/EFI/grub/grubx64.efi file will be created. This is the GRUB boot image that UEFI will load and start.

Configuring GRUB

OK, now UEFI has the GRUB image it needs to boot. But we still need to configure GRUB itself so it finds and boots your kernel and initramfs. This is done by performing the following steps. Since boot-update doesn't yet support UEFI, we will not use boot-update directly and will create a /boot/grub/grub.cfg file manually that looks like this:

set timeout=3
set gfxmode=auto
insmod efi_gop
insmod efi_uga

menuentry "Funtoo Linux genkernel - kernel-debian-sources-x86_64-3.2.35-2" {  
    insmod part_gpt
    insmod fat  
    set root=(hostdisk//dev/sda,gpt1)  
    search --no-floppy --fs-uuid --set __REPLACE_UUID_OF_SDA1__
    linux /kernel-debian-sources-x86_64-3.2.35-2 real_root=/dev/sda3
    initrd /initramfs-debian-sources-x86_64-3.2.35-2  
    set gfxpayload=keep
}
set default=0

Note the search line where it says __REPLACE_UUID_OF_SDA1__ above. You will need to run blkid /dev/sda1 and use the UUID value that is displayed. For example, on my system, I need to use C34B-19CF. You can also change the menuentry line text in quotes to say whatever you want, and the linux and initrd lines should reference your kernel versions in /boot. As above, use the path / instead of /boot as the path should be relative to the root of the VFAT filesystem.

Known Issues

With pure UEFI boot mode, with legacy mode disabled, following error expected:

  • video driver not supported, boot hangs, hard reboot required.

Choose UEFI first, next legacy driver. It depends on motherboard vendor and efi bios version. In UEFI bios choose grub option, if your succeeded with above guide, additional menu should appear in Boot Menu, otherwise it boots into EFI shell:

  • grub:NAME of you hard drive

Done!

Remember to follow all other steps in the regular Funtoo Install Guide. Assuming you did everything correctly, your system should now boot via UEFI! We will be adding UEFI support to boot-update soon to make this process easier.