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[Brad Figg <brad.figg@xxxxxxxxxxxxx>]

This bug is missing log files that will aid in diagnosing the problem.
>From a terminal window please run:

apport-collect 1457781

and then change the status of the bug to 'Confirmed'.

If, due to the nature of the issue you have encountered, you are unable
to run this command, please add a comment stating that fact and change
the bug status to 'Confirmed'.

This change has been made by an automated script, maintained by the
Ubuntu Kernel Team.

** Changed in: linux (Ubuntu)
       Status: New => Incomplete

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https://bugs.launchpad.net/bugs/1457781

Title:
  armhf: cpufreq doesn't autoload by default

Status in linux package in Ubuntu:
  Incomplete

Bug description:
  SRU Justification:

      Impact: upon boot, frequency scaling is not working.

      Fix: Apply the patches, recompile and reboot.

      Testcase: Try booting a beaglebone with and without a patched
  kernel.

  With this series applied there should be:

  ubuntu@beaglebone:~$ ls -la /sys/devices/system/cpu/cpu0/cpufreq/
  total 0
  drwxr-xr-x 3 root root    0 May 22 07:03 .
  drwxr-xr-x 5 root root    0 May 22 07:03 ..
  -r--r--r-- 1 root root 4096 May 22 07:03 affected_cpus
  -r-------- 1 root root 4096 May 22 07:03 cpuinfo_cur_freq
  -r--r--r-- 1 root root 4096 May 22 07:03 cpuinfo_max_freq
  -r--r--r-- 1 root root 4096 May 22 07:03 cpuinfo_min_freq
  -r--r--r-- 1 root root 4096 May 22 07:03 cpuinfo_transition_latency
  -r--r--r-- 1 root root 4096 May 22 07:03 related_cpus
  -r--r--r-- 1 root root 4096 May 22 07:03 scaling_available_frequencies
  -r--r--r-- 1 root root 4096 May 22 07:03 scaling_available_governors
  -r--r--r-- 1 root root 4096 May 22 07:03 scaling_cur_freq
  -r--r--r-- 1 root root 4096 May 22 07:03 scaling_driver
  -rw-r--r-- 1 root root 4096 May 22 04:43 scaling_governor
  -rw-r--r-- 1 root root 4096 May 22 07:03 scaling_max_freq
  -rw-r--r-- 1 root root 4096 May 22 07:03 scaling_min_freq
  -rw-r--r-- 1 root root 4096 May 22 07:03 scaling_setspeed
  drwxr-xr-x 2 root root    0 May 22 07:03 stats
  ubuntu@beaglebone:~$

  With an unpatched kernel, until the cpufreq module is loaded, that
  directory doesn't exist.

  ...

  While cpufreq support on armhf is available for a while, if support is
  compiled as a kernel module, the corresponding module doesn't autoload
  by default, and thus frequency scaling is not active upon boot until a
  user manually load it (or until /etc/modules is modified to forcibly
  load it).

  While in Trusty cpufreq was built-in on armhf, starting with Utopic we
  made support available as a kernel module, making people think that
  cpufreq was either broken or missing in their new kernels.

  To fix it, revert back that decision and make cpufreq compiled-in
  again on armhf - it affects Utopic and Vivid kernels.

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