ACPI vs DT at runtime

[Olof Johansson]

On Thu, Nov 21, 2013 at 11:01 AM, Russell King - ARM Linux
<linux at arm.linux.org.uk> wrote:
> On Thu, Nov 21, 2013 at 10:59:41AM -0800, Olof Johansson wrote:
>> On Thu, Nov 21, 2013 at 10:54 AM, Russell King - ARM Linux
>> <linux at arm.linux.org.uk> wrote:
>> > This depends what you want from ACPI, and what market ACPI is being
>> > targetted at.
>>
>> We're talking ACPI on servers here.
>
> Now read the rest of my email, thanks.

Yes, there are use cases for ACPI on embedded, which is what Intel is
getting into and the standard is changing accordingly. On embedded ARM
we're quite comfortable with DT for now, so it doesn't make sense to
consider ACPI there just for the sake of it, as far as I am concerned.

And, on servers, using the embedded-targeted bindings that expose all
hardware details (and leaving implementation to the kernel) seems
counter to the main target of forwards- and backwards compatibility.
That can only really be achieved by getting rid of hardware diversity
and reaching standardized hardware platforms with discoverable
devices. Keeping the complex parts of power management out of the
kernel on those platforms is going to be important too.


-Olof