amdtemp does not find my CPU.

[Jeremy Chadwick]

On Fri, Mar 15, 2013 at 03:16:19PM -0400, Jim Ohlstein wrote:
> On 3/15/13 12:15 PM, Zoran Kolic wrote:
> > After I installed 9.1 amd64 on node with amd 8120,
> > I was not able to read temperatures out of the box.
> > I fetched source for head module and compiled. And
> > loaded module. Still nothing. I assume my cpu is
> > a bit different.
> > Best regards
> 
> The module from head "works" for me with an 8120 on 9.1 stable (r247893)
> though the results are inconsistent. I am not certain of how useful they
> are.
> 
> # sysctl hw.model
> hw.model: AMD FX(tm)-8120 Eight-Core Processor
> 
> # kldstat | grep amd
>  5    1 0xffffffff8183e000 1043     amdtemp.ko
> 
> # sysctl -a | grep dev.amdtemp
> dev.amdtemp.0.%desc: AMD CPU On-Die Thermal Sensors
> dev.amdtemp.0.%driver: amdtemp
> dev.amdtemp.0.%parent: hostb4
> dev.amdtemp.0.sensor_offset: 0
> dev.amdtemp.0.core0.sensor0: 47.7C
> 
> Here are results taken at 0.1 second intervals using a shell script:
> 
> dev.amdtemp.0.core0.sensor0: 42.1C
> dev.amdtemp.0.core0.sensor0: 42.2C
> dev.amdtemp.0.core0.sensor0: 42.0C
> dev.amdtemp.0.core0.sensor0: 42.1C
> dev.amdtemp.0.core0.sensor0: 41.8C
> dev.amdtemp.0.core0.sensor0: 41.7C
> dev.amdtemp.0.core0.sensor0: 51.1C
> dev.amdtemp.0.core0.sensor0: 51.0C
> dev.amdtemp.0.core0.sensor0: 50.7C
> dev.amdtemp.0.core0.sensor0: 50.5C
> dev.amdtemp.0.core0.sensor0: 50.1C
> dev.amdtemp.0.core0.sensor0: 49.8C
> dev.amdtemp.0.core0.sensor0: 49.5C
> dev.amdtemp.0.core0.sensor0: 49.2C
> dev.amdtemp.0.core0.sensor0: 49.2C
> 
> 
> and again:
> 
> dev.amdtemp.0.core0.sensor0: 41.5C
> dev.amdtemp.0.core0.sensor0: 41.2C
> dev.amdtemp.0.core0.sensor0: 40.8C
> dev.amdtemp.0.core0.sensor0: 40.8C
> dev.amdtemp.0.core0.sensor0: 41.0C
> dev.amdtemp.0.core0.sensor0: 41.3C
> dev.amdtemp.0.core0.sensor0: 41.6C
> dev.amdtemp.0.core0.sensor0: 41.3C
> dev.amdtemp.0.core0.sensor0: 54.0C
> dev.amdtemp.0.core0.sensor0: 53.7C
> dev.amdtemp.0.core0.sensor0: 53.3C
> dev.amdtemp.0.core0.sensor0: 53.1C
> dev.amdtemp.0.core0.sensor0: 52.7C
> dev.amdtemp.0.core0.sensor0: 52.3C
> dev.amdtemp.0.core0.sensor0: 52.1C
> dev.amdtemp.0.core0.sensor0: 51.7C
> dev.amdtemp.0.core0.sensor0: 51.5C
> 
> You can see during each series there are sudden increases of over 9C and
> almost 13C respectively.
>
> The same effect is seen if I track any of the individual cores with
> "dev.cpu.[0-7].temperature". Here's an example with a 9C jump in 0.1 second.
> 
> dev.cpu.3.temperature: 41.5C
> dev.cpu.3.temperature: 41.5C
> dev.cpu.3.temperature: 41.7C
> dev.cpu.3.temperature: 41.7C
> dev.cpu.3.temperature: 41.3C
> dev.cpu.3.temperature: 41.0C
> dev.cpu.3.temperature: 40.7C
> dev.cpu.3.temperature: 49.8C
> dev.cpu.3.temperature: 49.5C
> dev.cpu.3.temperature: 49.2C
> dev.cpu.3.temperature: 48.8C
> dev.cpu.3.temperature: 48.6C
> dev.cpu.3.temperature: 48.2C
> dev.cpu.3.temperature: 48.0C
> 
> I don't have hands on access to this box as it's in a datacenter 1000
> miles from me, but the techs there had a look and all "seems to be OK".

1. While it's certainly possible the DTS reading routines and/or the
calculation formulas may be wrong in amdtemp(4), possibly for your model
of CPU, it is also certainly possible that what you're seeing is normal
and fully justified.  This is especially the case for the
dev.cpu.X.temperature nodes on the K8 family.

Respectfully, not combatively nor dismissively: you've not provided a
comparison base to prove there's an issue.  You would need to provide
data from Linux (I forget what daemon/tool they have to get this) or
Windows (Core Temp).

2. I have a gut feeling I know what may be causing what you're seeing,
but I need you to provide verbatim the shell script you're using.

3. Why has no one CC'd the driver maintainers nor individuals who have
committed/touched this driver?  Those people are:

Jung-uk KIM <jkim at FreeBSD.org>
Rui Paulo <rpaulo at FreeBSD.org>
Norikatsu SHIGEMURA <nork at FreeBSD.org>

-- 
| Jeremy Chadwick                                   jdc at koitsu.org |
| UNIX Systems Administrator                http://jdc.koitsu.org/ |
| Mountain View, CA, US                                            |
| Making life hard for others since 1977.             PGP 4BD6C0CB |