[coreboot] vboot

[David Hendricks]

On Fri, Jul 6, 2018 at 8:21 AM, Akendo <akendo at akendo.eu> wrote:
> Awesome Thanks!
>
> Can you tell me what the state is with vboot for a x220 is (as an example)?
>
> I did ask in the IRC and someone told me, that there is some work done
> on this topic. Also that no code contribution are necessary, but rather
> review (and testing I guess).
>
> From what I have seen in the code only google based laptop are supported
> for vboot. More might be possible, but I wasn't able to quickly identify
> them all.
>
> From what I have seen on the review pages, most changes there for vboot
> should not affect the x220, or do I get it wrong?

Although vboot is agnostic to CPU/SoC, it has a few system
requirements. Off the top of my head:
- There must be a read-only copy of the firmware stored on the boot
ROM. This requires a write-protection mechanism (present in SPI flash
parts) and enough capacity to store both read-only and rewriteable
copies.
- There are some variables (inputs) which vboot needs to read at
runtime, such as write-protect enabled/disabled and which mode
(normal/dev) you're in. These can come reading GPIOs, from querying an
EC, etc.

I don't know off-hand if anybody has put serious effort into using
vboot on the x220 or similar laptops. Chromebooks are designed with
the necessary capabilities in mind, so you may need to get creative to
find substitutes on hardware that was not designed with vboot in mind.
It would be a really neat project to try if you have time :-)