]> git.kernelconcepts.de Git - karo-tx-linux.git/commit
intel_idle: export both C1 and C1E
authorLen Brown <len.brown@intel.com>
Sat, 2 Feb 2013 06:31:56 +0000 (01:31 -0500)
committerLen Brown <len.brown@intel.com>
Wed, 13 Feb 2013 23:22:08 +0000 (18:22 -0500)
commit32e9518005c8dd9ed668f40f98632c8186df4909
tree277dde14dec62b8734d404f74f55335ce354d43f
parente022e7eb90f3edb83f9ff77825eda3d1b3a2f2e0
intel_idle: export both C1 and C1E

Here we disable HW promotion of C1 to C1E
and export both C1 and C1E and distinct C-states.

This allows a cpuidle governor to choose a lower latency
C-state than C1E when necessary to satisfy performance
and QOS constraints -- and still save power versus polling.
This also corrects the erroneous latency previously reported
for C1E -- it is 10usec, not 1usec.

Note that if you use "intel_idle.max_cstate=N",
then you must increment N by 1 to get the same behavior
after this change.

Signed-off-by: Len Brown <len.brown@intel.com>
drivers/idle/intel_idle.c