Re: [Xen-devel] HVMLite / PVHv2 - using x86 EFI boot entry

[Matt Fleming <matt@codeblueprint.co.uk>]

On Wed, 13 Apr, at 12:03:12PM, Roger Pau Monné wrote:
> 
> I don't get this, the "reset/shutdown" hypercall requires the following 
> steps from Dom0 (it's not as simple as calling a hypercall):
> 
> The way to perform a full system power off from Dom0 is different than 
> what's done in a DomU guest. In order to perform a power off from Dom0 the 
> native ACPI path should be followed, but the guest should not write the 
> `SLP_EN` bit to the Pm1Control register. Instead the 
> `XENPF_enter_acpi_sleep` hypercall should be used, filling the following 
> data in the `xen_platform_op` struct:
> 
>     cmd = XENPF_enter_acpi_sleep
>     interface_version = XENPF_INTERFACE_VERSION
>     u.enter_acpi_sleep.pm1a_cnt_val = Pm1aControlValue
>     u.enter_acpi_sleep.pm1b_cnt_val = Pm1bControlValue
> 
> At which point it means that we are either going to duplicate ACPICA code 
> into the HVMlite's custom EfiReset() service, or we are going to call into 
> ACPICA, which is what we already do now.

Fair enough, I wasn't aware that you needed to call into ACPI to
perform the reset.