On Sun, Dec 8, 2013 at 3:44 AM, Arnd Bergmann [off-list ref] wrote:

I'd agree as soon as someone can convince me that we actually want ACPI
support in the kernel for ARM64 servers. As far as I'm concerned it's quite
possible that the people who have worked on this for the past couple of
years behind closed doors know what they are doing and it will all be
good, but it's also possible that it turns into a huge trainwreck once
we see multiple implementations that have fundamentally incompatible
requirements regarding what they want from ACPI and we end up not doing
it at all.

Here is a piece I've noticed very clearly in the GPIO subsystem:

ACPI is persued for x86 servers, desktops by all vendors. For
embedded x86 it is persued by Intel *ONLY*. We still get several
embedded GPIO drivers for x86 that use ISA-style portmapped I/O
probing (!)

So, hehe, in init/Kconfig there is still the much-debated Kconfig
option "EMBEDDED"...

Should ACPI for ARM64 be depends on !EMBEDDED?

Yours,
Linus Walleij