[Qemu-devel] [PATCH RFC 0/7] pass cpu online/offline event bewteen QEMU and linux kernel by ACPI Embedded Controller

[liguang]

patch 1 adds ACPI Embedded Controller (EC),
refer-to:
ACPI SPEC v5 chapter 12
"ACPI Embedded Controller Interface Specification"

EC is a standard ACPI device, it plays flexible roles,
especially be event carrier, it can pass events between platform
and OS, so OS can execute _Qxx method which defined
by yourself and query EC's ACPI space which can be a buffer for
many purposes

here, I want to deliver CPU online/offline event between
OS and QEMU for CPU hotplug feature, then we will don't
need to "echo 1 > /sys/devices/system/cpu/cpu1/online"
again after 'cpu-add' and also for offline to do real cpu
removal.
what I am trying to do is emulated physical addition/removal
(like described by linux kernel document for cpu hotplug --
linux-2.6/Documentation/cpu-hotplug.txt) for QEMU.

these RFC patches are sent for demo what I am trying to do.

the design process simply like following:

cpu-add/del --> EC space & sci setting --> kernel EC driver gpe handler
                                                  I
                                                  V
                                      listen cpu hotplug event
                                                  I
                                                  V
                                      query EC space for cpu status
                                                  I
                                                  V
                                                                        trigger 
cpu online/offline process


Li Guang (7)
         acpi: add ACPI Embedded Controller support
         ich9: add notifer for ec to generate sci
         ec: add operations for _Qxx events
         piix4: add notifer for ec to generate sci
         piix4: add events for cpu hotplug
         qmp: add 'cpu-del' command
         pc: add EC qdev init for piix & q35

default-configs/x86_64-softmmu.mak |   1 +
hw/acpi/Makefile.objs              |   1 +
hw/acpi/ec.c                       | 225 ++++++++++++++++++++++++++++++++++++
hw/acpi/ich9.c                     |  15 +++++++++++++++
hw/acpi/piix4.c                    |  22 ++++++++++++++
hw/i386/pc.c                       |  30 ++++++++++++++++++++++++++++--
hw/i386/pc_piix.c                  |   7 +
hw/i386/pc_q35.c                   |   6 +
include/hw/acpi/ec.h               |  39 ++++++
include/hw/acpi/ich9.h             |   1 +
include/hw/boards.h                |   5 +++--
include/hw/i386/pc.h               |   1 +
qapi-schema.json                   |  13 +++++++++++++
qmp-commands.hx                    |  23 +++++++++++++++++++++++
qmp.c                              |   9 +++++++++
15 files changed, 390 insertions(+), 8 deletions(-)
 create mode 100644 hw/acpi/ec.c
 create mode 100644 include/hw/acpi/ec.h