Re: [PATCH] ArmVirtPkg/PlatformHasAcpiDtDxe: allow manual override for DT installation

[Laszlo Ersek <lersek@redhat.com>]

On 03/29/17 18:17, Ard Biesheuvel wrote:
> On 29 March 2017 at 17:09, Jon Masters <jcm@redhat.com> wrote:
>> Thanks Laszlo. A quick note from me that regardless of this discussion I will be pushing to ensure the version Red Hat ships makes ACPI the default with it being extremely painful to use DT. It is time the ecosystem got with the program we all agreed upon and there will be no more excuses.
>>
> 
> This has *nothing* to do with the ecosystem. This has to do with
> existing users of ArmVirtQemu (admittedly, a small fraction) that will
> be forced to compile their UEFI images from source because we made a
> backwards incompatible change.
> 
> I am 100% on board with making ACPI and DT mutually exclusive. But I
> don't believe for a second that 'everybody just exposes ACPI and DT at
> the same time' if this gets merged.

That's where we disagree, 100%.

> That happens because people are
> clueless, not because they are deliberately spending time and effort
> on producing two hardware descriptions.

If this were true, then the kernel's preference would have been changed
to ACPI aeons ago (assuming both DT and ACPI were present). ACPI is
superior to DT (cue again Grant Likely's blog post), yet kernel people
resist it. That's not cluelessness. If the kernel's DT camp has any
influence on platform vendors (and that's rather more a "given that"
than an "if"), when they find out about this loophole, I expect them to
actively recommend it as a way to perpetuate the status quo.

IMO, with this patch you are eviscerating the work we've been doing in
the last few weeks. Well, politics is nasty.

Laszlo