Installing UEFI

ACCEPT_KEYWORDS="~amd64" emerge -av =sys-boot/syslinux-6.02_pre16 

Prepare Partition

The first partition will be the EFI storage, make sure it's at least 512M (this is a FAT32 restriction). In the example below we've made the first one 1G.

cfdisk /dev/sda
mkfs.msdos -F 32 -n 'Boot' /dev/sda1
sfdisk -l -u M /dev/sda

Disk /dev/sda: 121601 cylinders, 255 heads, 63 sectors/track
Units: 1MiB = 1024*1024 bytes, blocks of 1024 bytes, counting from 0

   Device Boot Start   End    MiB    #blocks   Id  System
/dev/sda1   *     0+   972-   973-    995998+  ef  EFI (FAT-12/16/32)
/dev/sda2       972+  2925-  1954-   2000092+  82  Linux swap / Solaris
/dev/sda3      2925+ 34177- 31252-  32001480   83  Linux
/dev/sda4     34177+ 953869- 919693- 941764981+  83  Linux

Install Bootloader

mount /dev/sda3 /mnt/gentoo
mkdir -p /mnt/gentoo/boot/efi
mount /dev/sda1 /boot/efi

Registering with EFI

efibootmgr -c -d /dev/sda -p 1 -l \\EFI\\Path\\syslinux.efi -L Gentoo

See Also