Public bug reported:

[Impact]
Some HiSilicon SoCs do not implement registers that the cpufreq subsystem uses 
to calculate current performance. This can result in undefined data being used 
in internal calculations, and being exposed to userspace via sysfs. 

[Test Case]

[Fix]

[Regression Risk]
The fix is a quirk restricted to specific SoCs. It does rely on firmware 
behaving (overloading the desired_perf register w/ a correct actual perf 
value), so changes in firmware could lead to regressions.

** Affects: linux (Ubuntu)
     Importance: Undecided
     Assignee: dann frazier (dannf)
         Status: In Progress

** Affects: linux (Ubuntu Bionic)
     Importance: Undecided
         Status: New

** Affects: linux (Ubuntu Cosmic)
     Importance: Undecided
         Status: New

** Affects: linux (Ubuntu Disco)
     Importance: Undecided
     Assignee: dann frazier (dannf)
         Status: In Progress

** Also affects: linux (Ubuntu Disco)
   Importance: Undecided
       Status: New

** Also affects: linux (Ubuntu Bionic)
   Importance: Undecided
       Status: New

** Also affects: linux (Ubuntu Cosmic)
   Importance: Undecided
       Status: New

** Changed in: linux (Ubuntu Disco)
       Status: New => In Progress

** Changed in: linux (Ubuntu Disco)
     Assignee: (unassigned) => dann frazier (dannf)

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https://bugs.launchpad.net/bugs/1821620

Title:
  Add HiSilicon SoC quirk for cpufreq

Status in linux package in Ubuntu:
  In Progress
Status in linux source package in Bionic:
  New
Status in linux source package in Cosmic:
  New
Status in linux source package in Disco:
  In Progress

Bug description:
  [Impact]
  Some HiSilicon SoCs do not implement registers that the cpufreq subsystem 
uses to calculate current performance. This can result in undefined data being 
used in internal calculations, and being exposed to userspace via sysfs. 

  [Test Case]

  [Fix]

  [Regression Risk]
  The fix is a quirk restricted to specific SoCs. It does rely on firmware 
behaving (overloading the desired_perf register w/ a correct actual perf 
value), so changes in firmware could lead to regressions.

To manage notifications about this bug go to:
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