Re: [PATCH v4 1/5] treewide: Consolidate Apple DMI checks

[Mika Westerberg <mika.westerberg-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>]

On Tue, Aug 01, 2017 at 02:10:41PM +0200, Lukas Wunner wrote:
> We're about to amend ACPI bus scan with DMI checks whether we're running
> on a Mac to support Apple device properties in AML.  The DMI checks are
> performed for every single device, adding overhead for everything x86
> that isn't Apple, which is the majority.  Rafael and Andy therefore
> request to perform the DMI match only once and cache the result.
> 
> Outside of ACPI various other Apple DMI checks exist and it seems
> reasonable to use the cached value there as well.  Rafael, Andy and
> Darren suggest performing the DMI check in arch code and making it
> available with a header in include/linux/platform_data/x86/.
> 
> To this end, add early_platform_quirks() to arch/x86/kernel/quirks.c
> to perform the DMI check and invoke it from setup_arch().  Switch over
> all existing Apple DMI checks, thereby fixing two deficiencies:
> 
> * They are now #defined to false on non-x86 arches and can thus be
>   optimized away if they're located in cross-arch code.
> 
> * Some of them only match "Apple Inc." but not "Apple Computer, Inc.",
>   which is used by BIOSes released between January 2006 (when the first
>   x86 Macs started shipping) and January 2007 (when the company name
>   changed upon introduction of the iPhone).
> 
> Cc: Lv Zheng <lv.zheng-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
> Cc: Ingo Molnar <mingo-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
> Cc: H. Peter Anvin <hpa-YMNOUZJC4hwAvxtiuMwx3w@public.gmane.org>
> Cc: Thomas Gleixner <tglx-hfZtesqFncYOwBW4kG4KsQ@public.gmane.org>
> Cc: Bjorn Helgaas <bhelgaas-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
> Cc: Matt Fleming <matt-mF/unelCI9GS6iBeEJttW/XRex20P6io@public.gmane.org>
> Cc: Ard Biesheuvel <ard.biesheuvel-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
> Cc: Andreas Noever <andreas.noever-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
> Cc: Michael Jamet <michael.jamet-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
> Cc: Yehezkel Bernat <yehezkel.bernat-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
> Cc: Mika Westerberg <mika.westerberg-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>

For the thunderbolt bits:

Acked-by: Mika Westerberg <mika.westerberg-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
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