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. -- MST
