BDW-X idle workaround: force enable MWAIT

for internal debug only

BDW-X does not currently enable MWAIT, does not export any ACPI C-states,
and so it runs in C0 all the time (doesn't even have C1).

This hack patch forces MWAIT to be enabled
and thus allows intel_idle to load.

This patch has been tested to allow 99% PC6 residency, vs 0% out of box.

Signed-off-by: Len Brown <>
1 file changed