kernel/linux.git/drivers/cpufreq, branch v4.14.85

cpufreq: imx6q: add return value check for voltage scale

2018-12-01T08:42:53+00:00

[ Upstream commit 6ef28a04d1ccf718eee069b72132ce4aa1e52ab9 ] Add return value check for voltage scale when ARM clock rate change fail. Signed-off-by: Anson Huang Acked-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin

cpufreq: dt: Try freeing static OPPs only if we have added them

2018-11-13T19:14:54+00:00

[ Upstream commit 51c99dd2c06b234575661fa1e0a1dea6c3ef566f ] We can not call dev_pm_opp_of_cpumask_remove_table() freely anymore since the latest OPP core updates as that uses reference counting to free resources. There are cases where no static OPPs are added (using DT) for a platform and trying to remove the OPP table may end up decrementing refcount which is already zero and hence generating warnings. Lets track if we were able to add static OPPs or not and then only remove the table based on that. Some reshuffling of code is also done to do that. Reported-by: Niklas Cassel Tested-by: Niklas Cassel Signed-off-by: Viresh Kumar Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

cpufreq: conservative: Take limits changes into account properly

2018-11-13T19:14:45+00:00

commit da5e79bc70b84971d2b3a55fb252e34e51d81d48 upstream. If the policy limits change between invocations of cs_dbs_update(), the requested frequency value stored in dbs_info may not be updated and the function may use a stale value of it next time. Moreover, if idle periods are takem into account by cs_dbs_update(), the requested frequency value stored in dbs_info may be below the min policy limit, which is incorrect. To fix these problems, always update the requested frequency value in dbs_info along with the local copy of it when the previous requested frequency is beyond the policy limits and avoid decreasing the requested frequency below the min policy limit when taking idle periods into account. Fixes: abb6627910a1 (cpufreq: conservative: Fix next frequency selection) Fixes: 00bfe05889e9 (cpufreq: conservative: Decrease frequency faster for deferred updates) Reported-by: Waldemar Rymarkiewicz Cc: All applicable Signed-off-by: Rafael J. Wysocki Acked-by: Waldemar Rymarkiewicz Acked-by: Viresh Kumar Signed-off-by: Greg Kroah-Hartman

cpufreq: governor: Avoid accessing invalid governor_data

2018-09-09T17:55:58+00:00

commit 2a3eb51e30b9ac66fe1b75877627a7e4aaeca24a upstream. If cppc_cpufreq.ko is deleted at the same time that tuned-adm is changing profiles, there is a small chance that a race can occur between cpufreq_dbs_governor_exit() and cpufreq_dbs_governor_limits() resulting in a system failure when the latter tries to use policy->governor_data that has been freed by the former. This patch uses gov_dbs_data_mutex to synchronize access. Fixes: e788892ba3cc (cpufreq: governor: Get rid of governor events) Signed-off-by: Henry Willard [ rjw: Subject, minor white space adjustment ] Cc: 4.8+ # 4.8+ Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

cpufreq: intel_pstate: Register when ACPI PCCH is present

2018-07-25T09:25:08+00:00

commit 95d6c0857e54b788982746071130d822a795026b upstream. Currently, intel_pstate doesn't register if _PSS is not present on HP Proliant systems, because it expects the firmware to take over CPU performance scaling in that case. However, if ACPI PCCH is present, the firmware expects the kernel to use it for CPU performance scaling and the pcc-cpufreq driver is loaded for that. Unfortunately, the firmware interface used by that driver is not scalable for fundamental reasons, so pcc-cpufreq is way suboptimal on systems with more than just a few CPUs. In fact, it is better to avoid using it at all. For this reason, modify intel_pstate to look for ACPI PCCH if _PSS is not present and register if it is there. Also prevent the pcc-cpufreq driver from trying to initialize itself if intel_pstate has been registered already. Fixes: fbbcdc0744da (intel_pstate: skip the driver if ACPI has power mgmt option) Reported-by: Andreas Herrmann Reviewed-by: Andreas Herrmann Acked-by: Srinivas Pandruvada Tested-by: Andreas Herrmann Cc: 4.16+ # 4.16+ Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

cpufreq / CPPC: Set platform specific transition_delay_us

2018-07-22T12:28:42+00:00

commit d4f3388afd488ed15368fa7413b8bd6d1f98bb1d upstream. Add support to specify platform specific transition_delay_us instead of using the transition delay derived from PCC. With commit 3d41386d556d (cpufreq: CPPC: Use transition_delay_us depending transition_latency) we are setting transition_delay_us directly and not applying the LATENCY_MULTIPLIER. Because of that, on Qualcomm Centriq we can end up with a very high rate of frequency change requests when using the schedutil governor (default rate_limit_us=10 compared to an earlier value of 10000). The PCC subspace describes the rate at which the platform can accept commands on the CPPC's PCC channel. This includes read and write command on the PCC channel that can be used for reasons other than frequency transitions. Moreover the same PCC subspace can be used by multiple freq domains and deriving transition_delay_us from it as we do now can be sub-optimal. Moreover if a platform does not use PCC for desired_perf register then there is no way to compute the transition latency or the delay_us. CPPC does not have a standard defined mechanism to get the transition rate or the latency at the moment. Given the above limitations, it is simpler to have a platform specific transition_delay_us and rely on PCC derived value only if a platform specific value is not available. Signed-off-by: Prashanth Prakash Cc: 4.14+ # 4.14+ Fixes: 3d41386d556d (cpufreq: CPPC: Use transition_delay_us depending transition_latency) Signed-off-by: Rafael J. Wysocki Signed-off-by: Sudip Mukherjee Signed-off-by: Greg Kroah-Hartman

cpufreq: intel_pstate: Fix scaling max/min limits with Turbo 3.0

2018-07-03T09:24:56+00:00

commit ff7c9917143b3a6cf2fa61212a32d67cf259bf9c upstream. When scaling max/min settings are changed, internally they are converted to a ratio using the max turbo 1 core turbo frequency. This works fine when 1 core max is same irrespective of the core. But under Turbo 3.0, this will not be the case. For example: Core 0: max turbo pstate: 43 (4.3GHz) Core 1: max turbo pstate: 45 (4.5GHz) In this case 1 core turbo ratio will be maximum of all, so it will be 45 (4.5GHz). Suppose scaling max is set to 4GHz (ratio 40) for all cores ,then on core one it will be = max_state * policy->max / max_freq; = 43 * (4000000/4500000) = 38 (3.8GHz) = 38 which is 200MHz less than the desired. On core2, it will be correctly set to ratio 40 (4GHz). Same holds true for scaling min frequency limit. So this requires usage of correct turbo max frequency for core one, which in this case is 4.3GHz. So we need to adjust per CPU cpu->pstate.turbo_freq using the maximum HWP ratio of that core. This change uses the HWP capability of a core to adjust max turbo frequency. But since Broadwell HWP doesn't use ratios in the HWP capabilities, we have to use legacy max 1 core turbo ratio. This is not a problem as the HWP capabilities don't differ among cores in Broadwell. We need to check for non Broadwell CPU model for applying this change, though. Signed-off-by: Srinivas Pandruvada Cc: 4.6+ # 4.6+ Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

cpufreq: governors: Fix long idle detection logic in load calculation

2018-06-26T00:06:32+00:00

commit 7592019634f8473f0b0973ce79297183077bdbc2 upstream. According to current code implementation, detecting the long idle period is done by checking if the interval between two adjacent utilization update handlers is long enough. Although this mechanism can detect if the idle period is long enough (no utilization hooks invoked during idle period), it might not cover a corner case: if the task has occupied the CPU for too long which causes no context switches during that period, then no utilization handler will be launched until this high prio task is scheduled out. As a result, the idle_periods field might be calculated incorrectly because it regards the 100% load as 0% and makes the conservative governor who uses this field confusing. Change the detection to compare the idle_time with sampling_rate directly. Reported-by: Artem S. Tashkinov Signed-off-by: Chen Yu Acked-by: Viresh Kumar Cc: All applicable Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

cpufreq: Fix new policy initialization during limits updates via sysfs

2018-06-26T00:06:32+00:00

commit c7d1f119c48f64bebf0fa1e326af577c6152fe30 upstream. If the policy limits are updated via cpufreq_update_policy() and subsequently via sysfs, the limits stored in user_policy may be set incorrectly. For example, if both min and max are set via sysfs to the maximum available frequency, user_policy.min and user_policy.max will also be the maximum. If a policy notifier triggered by cpufreq_update_policy() lowers both the min and the max at this point, that change is not reflected by the user_policy limits, so if the max is updated again via sysfs to the same lower value, then user_policy.max will be lower than user_policy.min which shouldn't happen. In particular, if one of the policy CPUs is then taken offline and back online, cpufreq_set_policy() will fail for it due to a failing limits check. To prevent that from happening, initialize the min and max fields of the new_policy object to the ones stored in user_policy that were previously set via sysfs. Signed-off-by: Kevin Wangtao Acked-by: Viresh Kumar [ rjw: Subject & changelog ] Cc: All applicable Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

cpufreq: Reorder cpufreq_online() error code path

2018-05-30T05:52:38+00:00

[ Upstream commit b24b6478e65f140610ab1ffaadc7bc6bf0be8aad ] Ideally the de-allocation of resources should happen in the exact opposite order in which they were allocated. It helps maintain the code in long term, even if nothing really breaks with incorrect ordering. That wasn't followed in cpufreq_online() and it has some inconsistencies. For example, the symlinks were created from within the locked region while they are removed only after putting the locks. Also ->exit() should have been called only after the symlinks are removed and the lock is dropped, as that was the case when ->init() was first called. Signed-off-by: Viresh Kumar [ rjw: Subject ] Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman