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  1. 02 9月, 2009 2 次提交
    • N
      [CPUFREQ] update Doc for cpuinfo_cur_freq and scaling_cur_freq · da470db1
      由 Naga Chumbalkar 提交于 
      I think the way "cpuinfo_cur_info" and "scaling_cur_info" are defined under
./Documentation/cpu-freq/user-guide.txt can be enhanced. Currently, they are
both defined the same way: "Current speed/frequency" of the CPU, in KHz".

Below is a patch that distinguishes one from the other.

Regards,
- naga -

-----------------------------------------
Update description for "cpuinfo_cur_freq" and "scaling_cur_freq".

Some of the wording is drawn from comments found in
./drivers/cpufreq/cpufreq.c: cpufreq_out_of_sync():

 *      @old_freq: CPU frequency the kernel thinks the CPU runs at
 *      @new_freq: CPU frequency the CPU actually runs at
Signed-off-by: NNaga Chumbalkar <nagananda.chumbalkar@hp.com>
Signed-off-by: NDave Jones <davej@redhat.com>
      da470db1
    • D
      [CPUFREQ] Re-enable cpufreq suspend and resume code · ce6c3997
      由 Dominik Brodowski 提交于 
      Commit 4bc5d341 is broken and causes regressions:

(1) cpufreq_driver->resume() and ->suspend() were only called on
__powerpc__, but you could set them on all architectures. In fact,
->resume() was defined and used before the PPC-related commit
42d4dc3f complained about in 4bc5d341.

(2) Therfore, the resume functions in acpi_cpufreq and speedstep-smi
would never be called.

(3) This means speedstep-smi would be unusuable after suspend or resume.

The _real_ problem was calling cpufreq_driver->get() with interrupts
off, but it re-enabling interrupts on some platforms. Why is ->get()
necessary?

Some systems like to change the CPU frequency behind our
back, especially during BIOS-intensive operations like suspend or
resume. If such systems also use a CPU frequency-dependant timing loop,
delays might be off by large factors. Therefore, we need to ascertain
as soon as possible that the CPU frequency is indeed at the speed we
think it is. You can do this two ways: either setting it anew, or trying
to get it. The latter is what was done, the former also has the same IRQ
issue.

So, let's try something different: defer the checking to after interrupts
are re-enabled, by calling cpufreq_update_policy() (via schedule_work()).
Timings may be off until this later stage, so let's watch out for
resume regressions caused by the deferred handling of frequency changes
behind the kernel's back.
Signed-off-by: NDominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: NDave Jones <davej@redhat.com>
      ce6c3997
  3. 01 9月, 2009 6 次提交
  5. 31 8月, 2009 10 次提交
  7. 30 8月, 2009 2 次提交
  9. 29 8月, 2009 10 次提交
  11. 28 8月, 2009 10 次提交