cpufreq: Notify governors when cpus are hot-[un]plugged
Because cpufreq core and governors worry only about the online cpus, if a cpu is
hot [un]plugged, we must notify governors about it, otherwise be ready to expect
something unexpected.

We already have notifiers in the form of CPUFREQ_GOV_START/CPUFREQ_GOV_STOP, we
just need to call them now.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpufreq: Save user policy min/max instead of policy min/max during hotplug

When a CPU is hotplugged off, various fields of the policy are saved so
that they can be restored when the CPU is hotplugged back in.

The existing code saves the policy min/max field during hotplug remove and
restores it into user policy min/max during hotplug add. This results in
the loss of the user policy min/max values across a hotplug remove/add.

Fix it by saving the user policy min/max instead of policy min/max during
hotplug remove. During a hotplug add, after user policy min/max is
restored, the policy min/max is already recomputed. So, there's no risk of
going beyound any limits imposed by the CPUFREQ_ADJUST/INCOMPATIBLE
notifiers.

Change-Id: Ib8e09fa324c1f80f095c5754b5dcf2685e8e4a66
Signed-off-by: Saravana Kannan <skannan@codeaurora.org>
msm: cpufreq: Initialize cpufreq driver early at boot

MSM cpufreq driver registering with the CPUFreq framework during
late_initcall() may cause the device to be available a few seconds after
the clock driver is ready for changing frequency. This could be bad for
boot and/or thermal performance, since the cpu will continue to boot at
whatever frequency the bootloaders set it to.

Initialize cpufreq driver as part of device_initcalL() but only after
all the clock drivers have had a chance to initialize their devices.

Change-Id: Iaa4867108f59a368ee5b511d35ea2e8e219d39d3
Signed-off-by: Praveen Chidambaram <pchidamb@codeaurora.org>
msm: cpufreq: Always update frequency limits when core is online

Remove condition in msm_cpufreq_init() so that when cpu is set to
online, it will call set_cpu_freq() and update the frequency limits.

CRs-Fixed: 462816
Change-Id: I40ac33c9cb4b42590a83f9d61b74f23379f5642e
Signed-off-by: Jennifer Liu <chihning@codeaurora.org>
msm: cpufreq: Move cpu_frequency_* trace points from acpuclock to cpufreq

acpuclock is not used on newer targets, so move the trace points
in it up to the generic msm cpufreq driver. Also drop the use of
the 'trace_cpu_frequency' entirely, since it's already present in
generic cpufreq code.

As a side effect of this change, these trace events will no longer
track cpu frequency changes from the power-collapse path. Only
frequency changes coming from cpufreq will be tracked.

CRs-Fixed: 535512
Change-Id: Ib69d92f5d3209a7e36be678997b79bcdac92f953
Signed-off-by: Matt Wagantall <mattw@codeaurora.org>
Perf: Check perf activity on correct CPU

The CPU hotplug notifier is not always preempt safe.
So relying on smp_processor_id() is not correct.

Use the cpu id from the notifier as the target
CPU to check for perf activity before hotplug or power
collapse.

CRs-Fixed: 454688
Change-Id: I1a96b236904a2c8ae2f82bbceab4ca8a195395d1
Signed-off-by: Ashwin Chaugule <ashwinc@codeaurora.org>
Perf: Fix counts across power collapse

After entry and exit from power collapse, the perf pm_notifier was
calling perf_pmu_disable/enable functions from perf core. Perf core
maintains a counter that it uses to match disable and enable calls but
since pm_notifier is invoked asynchronously, the counter was getting a
non-zero value which prevented the pmu from being enabled. As a result of
this, we were seeing zero counts for some cores across power collapse.

Make the architecture specific calls directly from pm_notifier.

Change-Id: I744e190906a20e70e1e4798235215c385018b121
Signed-off-by: Sheetal Sahasrabudhe <sheetals@codeaurora.org>
cpufreq: ondemand: fix timer-related list corruption in store_powersave_bias()

The dbs_timer_init() call in store_powersave_bias() re-initializes the
dbs_info workqueue, call on dbs_timer_exit() to ensure
outstanding work is cleared prior to making this call. Also, grab the
percpu timer_mutex lock to avoid race conditions with respect to the
dbs timer.

Change-Id: I79f3d43eeb51d2d8e21edd0fe043d6583333951f
Signed-off-by: Osvaldo Banuelos <osvaldob@codeaurora.org>
ondemand: add sysfs entry for down_diff_multi_core

This change adds sysfs entry for the ondemand governor's attribute
down_differential_multi_core. This is required to be able to program
this knob to attain better perf/power for use cases like camcorder.

CRs-fixed: 561456
Change-Id: Ib7c1223215c6b714c286c231ed37f3abfae741c6
Signed-off-by: Krishna Vanka <kvanka@codeaurora.org>
msm: boards: Enable Krait Retention.
Add SPM sequences to do Krait retention for 8960,8930
and 8064. Also added a new rpmrs level containing the
latencies and power measurements for this new low power
state.

CRs-Fixed: 369864
Change-Id: Ib30a9a978cf38b35037810a4001c9277837acd4c
Signed-off-by: Girish Mahadevan <girishm@codeaurora.org>
____________________

msm: pm: Update spm retention sequence to support per core retention
On krait revision < 3, power driver is not using full spm sequence and
calling into trustzone as a part of executing krait retention.
Also krait retention is not supported on secondary cores.

krait pass3 is upgraded to use full spm sequence, hence add support
for per core retention and avoid calling into trustzone
while executing retention.

Change-Id: I6a2b3d7c4d0fd5b9a340957b16b940b7a09bbd91
Signed-off-by: Anji Jonnala <anjir@codeaurora.org>
msm: acpuclock-krait: Work-around retention corner-case

The CPU clock source MUXes cannot switch while a CPU is in
retention, but callers of acpuclock APIs may not known that
the CPU is in retention.

Work around this problem be always performing the CPU MUX
switch on the affected CPU using smp_call_function_single()
in cases where cross-calling might otherwise be possible.
The one exception to this is during hotplug code paths,
where cross-calling is expected by design (since the target
CPU is not online and cannot be in retention).

Change-Id: I76b6de436e71da7979f30bdce841f414c26bfe44
Signed-off-by: Matt Wagantall <mattw@codeaurora.org>