Re: [Qemu-devel] [PATCH v2 0/8] Add system_powerdown support on ARM for ACPI and DT

[Shannon Zhao]

On 2015/10/30 2:17, Wei Huang wrote:
> On 10/29/2015 09:27 AM, Shannon Zhao wrote:
>> ACPI SPEC 5.0 defines GPIO-signaled ACPI Events for Hardware-reduced
>> platforms(like ARM). It uses GPIO pin to trigger an event to the guest.
>> For QEMU, here we add PL061 GPIO controller and use PIN 3 for
>> system_powerdown, reserving PIN 0, 1, 2 for PCI hotplug, CPU hotplug and
>> memory hotplug.
>>
>> This patchset adds system_powerdown support on ARM through both ACPI and
>> DT ways. It adds a GPIO controller(here is PL061) in machine virt and
>> uses GPIO-singled event for ACPI while gpio-keys for DT. It can be
>> fetched from [1] and has been tested for the guests starting by ACPI or
>> DT while guests use systemd or acpid.
>>
>> a) ACPI way. Since Graeme send a patchset to make ACPI on ARM64 support
>> amba device[2], it could use PL061 directly without modification to its
>> kernel driver code. In addition, we should use ACPI to start VM,
>> referring to below script. QEMU_EFI.fd can be fetched from [3]. 
> 
> Hi Shannon,
> 
> Thanks for re-sending it. This is a desired feature because we don't
> want to rely on tricks (such as guest-agent) for external VM power
> management. I have tested V1 recently by back-porting to my in-house
> kernel; it worked well.
> 
> I will help review this new version.
> 
Thanks for your help:)

-- 
Shannon