EFI Variable Support via sysfs

modulename: efivars.ko

configname: CONFIG_EFI_VARS

Linux Kernel Configuration
└─>Firmware Drivers
└─>EFI (Extensible Firmware Interface) Support
└─>EFI Variable Support via sysfs
In linux kernel since version 3.10 (release Date: 2013-06-30)  
If you say Y here, you are able to get EFI (Extensible Firmware
Interface) variable information via sysfs. You may read,
write, create, and destroy EFI variables through this interface.

Note that using this driver in concert with efibootmgr requires
at least test release version 0.5.0-test3 or later, which is
available from:
<http://linux.dell.com/efibootmgr/testing/efibootmgr-0.5.0-test3.tar.gz>

Subsequent efibootmgr releases may be found at:
<http://github.com/vathpela/efibootmgr>

source code:
depends
CONFIG_EFI