linux-stable.git/drivers/cpufreq, branch linux-4.6.y

Revert "cpufreq: pcc-cpufreq: update default value of cpuinfo_transition_latency"

2016-08-16T07:33:19+00:00

commit da7d3abe1c9e5ebac2cf86f97e9e89888a5e2094 upstream.

This reverts commit 790d849bf811a8ab5d4cd2cce0f6fda92f6aebf2.

Using a v4.7-rc7 kernel on a HP ProLiant triggered following messages

 pcc-cpufreq: (v1.10.00) driver loaded with frequency limits: 1200 MHz, 2800 MHz
 cpufreq: ondemand governor failed, too long transition latency of HW, fallback to performance governor

The last line was shown for each CPU in the system.
Testing v4.5 (where commit 790d849b was integrated) triggered
similar messages. Same behaviour on a 2nd HP Proliant system.

So commit 790d849bf (cpufreq: pcc-cpufreq: update default value of
cpuinfo_transition_latency) causes the system to use performance
governor which, I guess, was not the intention of the patch.

Enabling debug output in pcc-cpufreq provides following verbose output:

 pcc-cpufreq: (v1.10.00) driver loaded with frequency limits: 1200 MHz, 2800 MHz
 pcc_get_offset: for CPU 0: pcc_cpu_data input_offset: 0x44, pcc_cpu_data output_offset: 0x48
 init: policy->max is 2800000, policy->min is 1200000
 get: get_freq for CPU 0
 get: SUCCESS: (virtual) output_offset for cpu 0 is 0xffffc9000d7c0048, contains a value of: 0xff06. Speed is: 168000 MHz
 cpufreq: ondemand governor failed, too long transition latency of HW, fallback to performance governor
 target: CPU 0 should go to target freq: 2800000 (virtual) input_offset is 0xffffc9000d7c0044
 target: was SUCCESSFUL for cpu 0

I am asking to revert 790d849bf to re-enable usage of ondemand
governor with pcc-cpufreq.

Fixes: 790d849bf (cpufreq: pcc-cpufreq: update default value of cpuinfo_transition_latency)
Signed-off-by: Andreas Herrmann 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman

cpufreq: Avoid false-positive WARN_ON()s in cpufreq_update_policy()

2016-08-10T10:54:46+00:00

commit 742c87bf27d3b715820da6f8a81d6357adbf18f8 upstream.

CPU notifications from the firmware coming in when cpufreq is
suspended cause cpufreq_update_current_freq() to return 0 which
triggers the WARN_ON() in cpufreq_update_policy() for no reason.

Avoid that by checking cpufreq_suspended before calling
cpufreq_update_current_freq().

Fixes: c9d9c929e674 (cpufreq: Abort cpufreq_update_current_freq() for cpufreq_suspended set)
Signed-off-by: Rafael J. Wysocki 
Acked-by: Viresh Kumar 
Signed-off-by: Greg Kroah-Hartman

Merge branches 'pm-opp-fixes', 'pm-cpufreq-fixes' and 'pm-cpuidle-fixes'

2016-05-06T11:16:22+00:00

* pm-opp-fixes:
  PM / OPP: Remove useless check

* pm-cpufreq-fixes:
  intel_pstate: Fix intel_pstate_get()
  cpufreq: intel_pstate: Fix HWP on boot CPU after system resume
  cpufreq: st: enable selective initialization based on the platform

* pm-cpuidle-fixes:
  ARM: cpuidle: Pass on arm_cpuidle_suspend()'s return value

intel_pstate: Fix intel_pstate_get()

2016-05-04T12:09:16+00:00

After commit 8fa520af5081 "intel_pstate: Remove freq calculation from
intel_pstate_calc_busy()" intel_pstate_get() calls get_avg_frequency()
to compute the average frequency, which is problematic for two reasons.

First, intel_pstate_get() may be invoked before the driver reads the
CPU feedback registers for the first time and if that happens,
get_avg_frequency() will attempt to divide by zero.

Second, the get_avg_frequency() call in intel_pstate_get() is racy
with respect to intel_pstate_sample() and it may end up returning
completely meaningless values for this reason.

Moreover, after commit 7349ec0470b6 "intel_pstate: Move
intel_pstate_calc_busy() into get_target_pstate_use_performance()"
sample.core_pct_busy is never computed on Atom, but it is used in
intel_pstate_adjust_busy_pstate() in that case too.

To address those problems notice that if sample.core_pct_busy
was used in the average frequency computation carried out by
get_avg_frequency(), both the divide by zero problem and the
race with respect to intel_pstate_sample() would be avoided.

Accordingly, move the invocation of intel_pstate_calc_busy() from
get_target_pstate_use_performance() to intel_pstate_update_util(),
which also will take care of the uninitialized sample.core_pct_busy
on Atom, and modify get_avg_frequency() to use sample.core_pct_busy
as per the above.

Reported-by: kernel test robot 
Link: http://marc.info/?l=linux-kernel&m=146226437623173&w=4
Fixes: 8fa520af5081 "intel_pstate: Remove freq calculation from intel_pstate_calc_busy()"
Fixes: 7349ec0470b6 "intel_pstate: Move intel_pstate_calc_busy() into get_target_pstate_use_performance()"
Signed-off-by: Rafael J. Wysocki

cpufreq: intel_pstate: Fix HWP on boot CPU after system resume

2016-05-02T11:48:15+00:00

Commit 41cfd64cf49fc "Update frequencies of policy->cpus only from
->set_policy()" changed the way the intel_pstate driver's ->set_policy
callback updates the HWP (hardware-managed P-states) settings.
A side effect of it is that if those settings are modified on the
boot CPU during system suspend and wakeup, they will never be
restored during subsequent system resume.

To address this problem, allow cpufreq drivers that don't provide
->target or ->target_index callbacks to use ->suspend and ->resume
callbacks and add a ->resume callback to intel_pstate to restore
the HWP settings on the CPUs that belong to the given policy.

Fixes: 41cfd64cf49fc "Update frequencies of policy->cpus only from ->set_policy()"
Tested-by: Srinivas Pandruvada 
Signed-off-by: Rafael J. Wysocki 
Acked-by: Viresh Kumar

Merge branch 'pm-cpufreq-fixes'

2016-04-29T12:22:25+00:00

* pm-cpufreq-fixes:
  cpufreq: intel_pstate: Fix processing for turbo activation ratio
  Revert "cpufreq: governor: Fix negative idle_time when configured with CONFIG_HZ_PERIODIC"

cpufreq: st: enable selective initialization based on the platform

2016-04-28T13:25:56+00:00

The sti-cpufreq does unconditional registration of the cpufreq-dt driver
which causes issue on an multi-platform build. For example, on Vexpress
TC2 platform, we get the following error on boot:

cpu cpu0: OPP-v2 not supported
cpu cpu0: Not doing voltage scaling
cpu: dev_pm_opp_of_cpumask_add_table: couldn't find opp table
	for cpu:0, -19
cpu cpu0: dev_pm_opp_get_max_volt_latency: Invalid regulator (-6)
...
arm_big_little: bL_cpufreq_register: Failed registering platform driver:
		vexpress-spc, err: -17

The actual driver fails to initialise as cpufreq-dt is probed
successfully, which is incorrect. This issue can happen to any platform
not using cpufreq-dt in a multi-platform build.

This patch adds a check to do selective initialization of the driver.

Fixes: ab0ea257fc58 (cpufreq: st: Provide runtime initialised driver for ST's platforms)
Signed-off-by: Sudeep Holla 
Acked-by: Viresh Kumar 
Acked-by: Lee Jones 
Cc: 4.5+  # 4.5+
Signed-off-by: Rafael J. Wysocki

cpufreq: intel_pstate: Fix processing for turbo activation ratio

2016-04-25T21:39:09+00:00

When the config TDP level is not nominal (level = 0), the MSR values for
reading level 1 and level 2 ratios contain power in low 14 bits and actual
ratio bits are at bits [23:16]. The current processing for level 1 and
level 2 is wrong as there is no shift done to get actual ratio.

Fixes: 6a35fc2d6c22 (cpufreq: intel_pstate: get P1 from TAR when available)
Signed-off-by: Srinivas Pandruvada 
Cc: 4.4+  # 4.4+
Signed-off-by: Rafael J. Wysocki

Revert "cpufreq: governor: Fix negative idle_time when configured with CONFIG_HZ_PERIODIC"

2016-04-25T00:39:20+00:00

Revert commit 0df35026c6a5 (cpufreq: governor: Fix negative idle_time
when configured with CONFIG_HZ_PERIODIC) that introduced a regression
by causing the ondemand cpufreq governor to misbehave for
CONFIG_TICK_CPU_ACCOUNTING unset (the frequency goes up to the max at
one point and stays there indefinitely).

The revert takes subsequent modifications of the code in question into
account.

Fixes: 0df35026c6a5 (cpufreq: governor: Fix negative idle_time when configured with CONFIG_HZ_PERIODIC)
Link: https://bugzilla.kernel.org/show_bug.cgi?id=115261
Reported-and-tested-by: Timo Valtoaho 
Cc: 4.5+  # 4.5+
Signed-off-by: Rafael J. Wysocki 
Acked-by: Viresh Kumar

Merge branch 'pm-cpufreq-fixes'

2016-04-21T18:57:46+00:00

* pm-cpufreq-fixes:
  cpufreq: Abort cpufreq_update_current_freq() for cpufreq_suspended set
  intel_pstate: Avoid getting stuck in high P-states when idle