xen/acpi: implement hook to notify Xen about entering sleep stateHEADmain

This is required so that ACPI power-off (entering S5) works as expected, as
the ACPI PM1a and PM1b blocks might not be accessible by dom0 directly.
Additionally, Xen also needs to do cleanup before entering a sleep state,
so it needs to be notified about it.

With this patch FreeBSD dom0 now powers off the host correctly:

acpi0: Powering system off...
(XEN) [   85.686598] arch/x86/hvm/emulate.c:415:d0v0 fixup p2m mapping for page fedc6 added
(XEN) [   85.687606] arch/x86/hvm/emulate.c:415:d0v0 fixup p2m mapping for page fbc10 added
(XEN) [   85.692357] Preparing system for ACPI S5 state.
(XEN) [   85.692702] Disabling non-boot CPUs ...
(XEN) [   85.694471] Broke affinity for IRQ9, new: {0-7}
[...]
(XEN) [   85.903118] Entering ACPI S5 state.

Should be a non-functional change when not running as a Xen dom0.

Reviewed by: kib
Sponsored by: Citrix Systems R&D
MFC after: 2 weeks
Differential revision: https://reviews.freebsd.org/D55504

0 files changed, 0 insertions, 0 deletions