How to know your BIOS name and version?

$sudo dmidecode | less

Thank you.

Because of the output of this I wanted to update coreboot and did everything in the "rookie guide lesson 1" [1], restarted, and there was still the same output in $sudo dmidecode | less.
They have no regular forum, just a bug tracker.
Does anybody have a clue?

[1] https://doc.coreboot.org/lessons/lesson1.html

With "did everything" I mean that I followed all the steps on that page.
I'm trying to update the coreboot on my Trisquel laptop.

It's a Lenovo Thinkpad T500.

This is why I'm think I'm running coreboot:
-
dmidecode 3.0
Getting SMBIOS data from sysfs.
SMBIOS 2.7 present.
8 structures occupying 406 bytes.
Table at 0x7FB13020.

Handle 0x0000, DMI type 0, 24 bytes
BIOS Information
Vendor: coreboot
Version: CBET4000 4.6-2030-g3ce678367c-dirty
Release Date: 11/07/2017
ROM Size: 8192 kB
Characteristics:
PCI is supported
PC Card (PCMCIA) is supported
BIOS is upgradeable
Selectable boot is supported
ACPI is supported
Targeted content distribution is supported
BIOS Revision: 4.0
Firmware Revision: 0.0
-
The laptop came with libreboot, as I ordered back then. But later the salesman I bought it from rethought his position about libreboot: coreboot comes with new updates every six months and he thought of libreboot as a "dead project", not expecting new updates as the maintainer is busy with personal occupations, so in his opinion coreboot would be the safer choice. So he grabbed my laptop on a Linux event and said he would provide a necessary update for free. He unpacked some hardware and went his way in some corner while I was having coffee and talked with a fellow Dutch Free Software enthusiast. Later the laptop salesman went out of business so I'm now on my own.