On Tuesday 10 December 2013, Mark Brown wrote:

On Tue, Dec 10, 2013 at 04:28:52AM +0100, Arnd Bergmann wrote:

quoted

On Monday 09 December 2013, Matthew Garrett wrote:

quoted

quoted

People are trying to deploy ACPI-based embedded x86, and most of the 
ACPI/DT integration discussion seems to have been based on the idea that 
this is a worthwhile thing to support. If we're not interested in doing 
so then we should probably make that a whole kernel decision rather than 
a per architecture one.

quoted

Well, except it's not an architecture independent decision. An embedded
x86 SoC will still be very much like a PC, just with a few things added
in and some other bits left out, and you can already describe it mostly

It's not just the SoC, it's also the rest of the board.  The patches the
Intel guys are submitting at the minute are mainly for the off-SoC
devices at least as far as I noticed.  This'll impact anyone who ends up
using ACPI, we need to at least pay attention to what's going on there.

Yes, but I'm not that worried about off-soc stuff, which tends to be
off the much simpler variety: a few MMIO or PIO registers, IRQs,
GPIOs or (with ACPI-5.0) devices on i2c and spi buses.

quoted

with plain ACPI-5.0. Also, there are only a couple of different non-PC style
devices that Intel is integrating into their SoCs, so we're talking
about a few dozen device drivers here.

It's going to be way more than that for the whole system, and you can't
assume that all the system integrators are going to pay a blind bit of
notice to the reference designs.  Some will just clone them but others
will bin them and do their own thing.

They won't be able to change the on-chip components for obvious reasons.

	Arnd