Restore broken ThunderX support in 12 by MFCing r343764?

[Ed Maste]

On Sun, 17 Feb 2019 at 20:29, <kraileth at elderlinux.org> wrote:
>
> Not being a developer though, I cannot judge if [r343764] cannot be MFC'd
> into 12-STABLE due to making invasive changes or if it simply never
> was because it was thought to be an improvement for 13 only and not an
> actually pretty vital fix for 12.

I suspect jchandra@ just didn't realize it's needed also on ThunderX,
and I did not encounter any trouble with the ThunderX systems I have.
It could just be that our (older) ThunderX reference firmware has
fewer regions in its ACPI info and so works fine without r343764.
Anyhow I've now merged the change to stable/12.

With respect to vt_efifb the tunable is a simple workaround, but we
really need this to work out-of-the-box. Do you have any further
details on the failure when vt_efifb is enabled?

Also, if you're aware of any other ThunderX issues please let me know.