The only place where the time is invalid is when the ACPI_CSTATE_FFH entry
method is not set. Otherwise for all the drivers, the time can be correctly
measured.

Instead of duplicating the CPUIDLE_FLAG_TIME_VALID flag in all the drivers
for all the states, just invert the logic by replacing it by the flag
CPUIDLE_FLAG_TIME_INVALID, hence we can set this flag only for the acpi idle
driver, remove the former flag from all the drivers and invert the logic with
this flag in the different governor.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Broadwell (BDW) is similar to Haswell (HSW), the preceding processor generation.

Currently, the only difference in their C-state tables is that PC3 max exit latency
is 33usec on HSW and 40usec on BDW.

Signed-off-by: Len Brown <len.brown@intel.com>

Power efficiency improves on Baytrail (Intel Atom Processor E3000)
when Linux disables C6 auto-demotion.

Based on work by Srinidhi Kasagar <srinidhi.kasagar@intel.com>.

Signed-off-by: Len Brown <len.brown@intel.com>
Cc: x86@kernel.org

Ivy Town idle state table will not be set as intended. Fix it.

Picked up by Coverity - CID 1201420/1201421.

Fixes: 0138d8f075 ("intel_idle: fine-tune IVT residency targets")
Signed-off-by: Christoph Jaeger <christophjaeger@linux.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

* pm-cpuidle:
  cpuidle: sysfs: Export target residency information
  intel_idle: fine-tune IVT residency targets
  tools/power turbostat: Run on Broadwell
  tools/power turbostat: simplify output, add Avg_MHz
  intel_idle: Add CPU model 54 (Atom N2000 series)
  intel_idle: support Bay Trail
  intel_idle: allow sparse sub-state numbering, for Bay Trail
  ACPI idle: permit sparse C-state sub-state numbers

Ivy Town processors have slightly different properties
than Ivy Bridge processors, particuarly as socket count grows.
Here we add dedicated tables covering 1-2 socket,
3-4 socket, and > 4 socket IVT configurations.

This reduces the frequency of deep transitions on those systems,
which can impact throughput.

Signed-off-by: Len Brown <len.brown@intel.com>

Subsystems that want to register CPU hotplug callbacks, as well as perform
initialization for the CPUs that are already online, often do it as shown
below:

	get_online_cpus();

	for_each_online_cpu(cpu)
		init_cpu(cpu);

	register_cpu_notifier(&foobar_cpu_notifier);

	put_online_cpus();

This is wrong, since it is prone to ABBA deadlocks involving the
cpu_add_remove_lock and the cpu_hotplug.lock (when running concurrently
with CPU hotplug operations).

Instead, the correct and race-free way of performing the callback
registration is:

	cpu_notifier_register_begin();

	for_each_online_cpu(cpu)
		init_cpu(cpu);

	/* Note the use of the double underscored version of the API */
	__register_cpu_notifier(&foobar_cpu_notifier);

	cpu_notifier_register_done();

Fix the intel-idle code by using this latter form of callback registration.

Cc: Len Brown <lenb@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Add CPU ID for Atom N2600/N2800 processors. Datasheets indicate support
for this, detailed information about potential quirks or limitations are
missing, though. So we just reuse the definition for the previous ATOM
series. Tests on N2800 systems showed that this addition is fine an can
reduce power consumption by about 0.25 W (personally confirmed on Intel
DN2800MT).

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Len Brown <len.brown@intel.com>

Bay Trail (BYT) is a family of Silvermont-core Atom Processor SOCs,
including the Intel Atom Processor Z36xxx and Z37xxx Series.

Although it shares the Silvermont core with Avoton,
BYT is optimized for mobile, and thus it supports
different power saving CPU idle states.

Note that not all versions of Bay Trail HW support all
of the states listed in the driver.

Signed-off-by: Len Brown <len.brown@intel.com>
Tested-by: Aubrey Li <aubrey.li@linux.intel.com>

Like acpi_idle, intel_idle compared sub-state numbers
to the number of supported sub-states -- discarding
sub-states numbers that were numbered >= the number of states.

But some Bay Trail SOCs use sparse sub-state numbers,
so we can't make such a comparison if we are going
to access those states.

So now we simply check that _some_ sub-states are
supported for the given state, and assume that the
sub-state number in our driver is valid.

In practice, the driver is correct, and even if it were not,
the hardware clips invalid sub-state requests to valid ones.

No entries in the driver require this change,
but Bay Trail will need it.

Signed-off-by: Len Brown <len.brown@intel.com>