This is a ThinkPad T480S, running Libreboot. Mate Kukri did it last night for coreboot, based on his ThinkPad T480 port.
And the T480 is also supported by Libreboot!
T480 and T480S both added to Libreboot last night. This is using Mate Kukri's excellent deguard utility, to disable the Intel Boot Guard.
New Libreboot release coming soon. It's the coreboot distro that I maintain, replacing proprietary BIOS/UEFI firmwaer.
https://browse.libreboot.org/lbmk.git/commit/?id=264928c6cdefb0b7a3c3ff01d4fe16fa4cc3cbd8
https://browse.libreboot.org/lbmk.git/commit/?id=c1b73269726a00255aa31ec02b3e55d281b397e6
https://browse.libreboot.org/lbmk.git/commit/?id=9dc3c86ae37db781b6bc4e745a57217c3511074b

