On Tue, Jun 11, 2013 at 10:00:36AM +0200, Gerd Hoffmann wrote:
Hi,
Yes and not just because of windows guests. ACPI spec is also very explicit that native hotplug is an optional feature. Test suites such as WHQL are known to test spec compliance.
/me looks a bit surprised.
This pretty much implies that any shpc bridge needs a second interface to the hotplug functionality which can be driven via ACPI. Or the firmware somehow handles this using smm (not sure this works for the IRQ though).
Do you know how this is handled by real hardware?
cheers, Gerd
SHPC is not very widely deployed on a PC.
Since most hardware vendors do care about windows support, the only way is a separate interface that is driven via ACPI. You then need an ACPI specific register to switch to standard SHPC. The SHPC spec even tells you as much.