intel_idle: Update support for Silvermont Core in Baytrail SOC
authorLen Brown <len.brown@intel.com>
Wed, 25 Mar 2015 03:23:20 +0000 (23:23 -0400)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 6 May 2015 20:03:50 +0000 (22:03 +0200)
commit64b22d90114136c3f66fef541c844bc2deb539c5
tree1369d165d7e935c4e3006d5f35df1c2161a2e5f2
parent12ea13bf83f15c5cf59b4039295f98b0d7a83881
intel_idle: Update support for Silvermont Core in Baytrail SOC

commit d7ef76717322c8e2df7d4360b33faa9466cb1a0d upstream.

On some Silvermont-Core/Baytrail-SOC systems,
C1E latency is higher than original specifications.
Although C1E is still enumerated in CPUID.MWAIT.EDX,
we delete the state from intel_idle to avoid latency impact.

Under some conditions, the latency of the C6N-BYT and C6S-BYT states
may exceed the specified values of 40 and 140 usec, respectively.
Increase those values to 300 and 500 usec; to assure
that the hardware does not violate constraints that may be set
by the Linux PM_QOS sub-system.

Also increase the C7-BYT target residency to 4.0 ms from 1.5 ms.

Signed-off-by: Len Brown <len.brown@intel.com>
Cc: Kumar P Mahesh <mahesh.kumar.p@intel.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/idle/intel_idle.c