Comment 12 for bug 1497520

For your Intel(R) Core(TM) i5-2520M CPU @ 2.50GHz processor, what is the normal minimum pstate? I ask because I have only seen on battery power resume from suspend issues that are related to Clock Modulation becoming enabled. i.e. I am wondering if 800MHz is a normal minimum frequency or below the normal minimum.

One way, would be to do:

cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_min_freq
1600000
1600000
1600000
1600000
1600000
1600000
1600000
1600000

and you can see that on my computer ( Intel(R) Core(TM) i7-2600K CPU @ 3.40GHz ), the minimum pstate is 16.

I'm not sure yet if our issues are related, but on my computer, I also am seeing odd stuff on resume from suspend (I didn't used to), but my CPU frequencies are not stuck low, but rather never go below pstate 24, even though the driver is asking for lower. I also get the same lack of restoring the proper governor on all the CPUs except CPU 0 (and note that for an S3 suspend CPU 0 is the one that never goes off line).

Example (no load):

pstate being asked for:

# rdmsr --bitfield 15:8 -d -a 0x199
16
16
16
16
16
16
16
16

pstate that I am getting:

# rdmsr --bitfield 15:8 -d -a 0x198
24
24
24
24
24
24
24
24

CPU freqs:

# grep MHz /proc/cpuinfo
cpu MHz : 2400.054
cpu MHz : 2399.921
cpu MHz : 2399.921
cpu MHz : 2399.921
cpu MHz : 2399.789
cpu MHz : 2399.789
cpu MHz : 2399.921
cpu MHz : 2399.921