[elrepo] No ondemand cpuspeed with 3.18.2-1.el6 kernel

[Robert Nichols]

I cannot get CPU ondemand frequency scaling working fully with
kernel-3.18.2-1.el6.elrepo.x86_64.

/sys/devices/system/cpu/cpu0/cpufreq/scaling_available_governors shows
only the "performance" and "powersave" governors available, no
"ondemand".

The driver listed in /sys/devices/system/cpu/cpu0/cpufreq/scaling_driver
is "intel_pstate". The script that starts the cpuspeed service does not
recognize that as compatible with "ondemand" and fails to start. I tried
patching the script to add "intel_pstate" to the list of acceptable
drivers. That allows the service to start, but I still have only the
"performance" and "powersave" drivers available.

Under the 2.6.32-504.3.3.el6.x86_64 kernel, the scaling_driver is
"acpi-cpufreq", so I followed the suggestion to update to acpi-2,
but that has made no difference with the new kernel.

Does anyone have any ideas? The "performance" governor runs my CPU at
"turbo" rate (3.9 GHz on a nominal 3.5GHz CPU), and I'd rather not
do that continuously. I do need the sound support in the 3.18 kernel.
(I suppose my alternative is to hack a backport of the new snd_hda_intel
kernel module into the 2.6 kernel.)

Gigabyte GA-Z97X-UD3H motherboard, Intel Core I5 4690K CPU,
Intel E3-1200 v3/4th Gen Core Processor HD Audio -- 8086:8CA0

-- 
Bob Nichols     "NOSPAM" is really part of my email address.
                 Do NOT delete it.