_GTS and _BFS were added to the suspend/resume flow
in the ACPI 2.0 specification.

Linux dutifully implemented _GTS and _BFS.
We discovered that it was rarely seen in systems
in the field.  Further, some of those systems had
AML so bogus that it could never work -- proof that
no other operating system supports _GTS and _BFS.
So we made _GTS and _BFS optional via modparam,
and disabled them by default.

But we've had to complicate some code to keep
this support in the kernel, as these methods are defined
to be evaluated very close to sleep entry and exit.
Indeed, no other AML is ever evaluated with interrupts off.

We have submitted a proposal for _GTS and _BFS
to be officially removed from the ACPI specification
on the next revision.  Here we remove it from Linux.
Signed-off-by: Len Brown <len.brown@intel.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>