A few days ago I found out that Dell had released a new version for my XPS13 (9360) BIOS.
Here are the steps I followed to update the BIOS (no USB key or wine or Windows boot required \o/).
Dell has a page that explains some of it.
Check BIOS version
First, check out your BIOS version:
$ sudo dmidecode -s bios-version [sudo] password for etienne: 1.3.5
Check latest BIOS version available online
If your BIOS is not up-to-date, download the latest BIOS (a .exe file named something like
XPS_9360_2.1.0.exe) from the Dell website.
Copy the BIOS file to the EFI folder
Copy this file to your
$ sudo cp ~/Downloads/XPS_930_2.1.0.exe /boot/efi
Update the BIOS with BIOS Flash Update
Reboot your XPS13 and push the F12 key during boot to start the Dell boot menu.
In the boot menu, choose "BIOS Flash Update":
A popup will open and you will be able to select the correct BIOS file (the one you just downloaded and copied to
Begin Flash Update and the new BIOS starts to update (it will only start if the power supply is plugged in):
After a few minutes the computer reboots with the new BIOS!
$ sudo dmidecode -s bios-version [sudo] password for etienne: 2.1.0