Created attachment 17169 [details]
The support for Intel ATOM

OK, I'll test this today

I'm sorry it will take additional time I failed at installing kernel from ubuntu... 
going back to gentoo...

It will take a few more days.

OK, here we go, I installed a Fedora Core 9, after multiple failings on Gentoo, Debian, Ubuntu... I haven't try Mandriva yet, but building a kernel on Mandrake gave me headaches many years ago...
So after having the r8169 now well-known Kernel Oops I achieved building and installing, and booting on a patched 2.6.27-rc2 kernel.
Here is my first output, I haven't tryed sensors or anything else yet :

# uname -a
Linux localhost.localdomain 2.6.27-rc2 #1 SMP Thu Aug 14 02:07:37 CEST 2008 i686 i686 i386 GNU/Linux

# modprobe coretemp && dmesg -c
coretemp coretemp.0: Unable to read IA32_TEMPERATURE_TARGET MSR
coretemp coretemp.1: Unable to read IA32_TEMPERATURE_TARGET MSR

Hello,

Ok, so it means it has no IA32_TEMPERATURE_TARGET, you may continue the test. This error is OK.

Well, good job, it seems to work, temperature moves correctly depending on cpu load.

#sensors
coretemp-isa-0000
Adapter: ISA adapter
Core 0:      +29.0°C  (crit = +95.0°C)                  

coretemp-isa-0001
Adapter: ISA adapter
Core 1:      +29.0°C  (crit = +95.0°C)                  

Is there something more to do to get it patched in 2.6.27-rc4 ?
Changing resolution?

This is way too late for 2.6.27. This patch is 2.6.28 material.

I tested this patch on 2.6.27-rc4 and 2.6.26.
This 2 messages are appearing in the log:

coretemp coretemp.0: Unable to read IA32_TEMPERATURE_TARGET MSR
coretemp coretemp.1: Unable to read IA32_TEMPERATURE_TARGET MSR

Reading the temperature works as expected on Atom Z530.
Thanks for this patch!

As of 2.6.28-rc9 this patch still isn't in the mainline tree.

The patch in comment #1 no longer applies to the upstream kernel. Rudolf, can we have an updated patch? Then post it to the lm-sensors list with proper description and your S-o-B and I'll pick it there. Thanks.

Perhaps the bug I just submitted is related to this one, or even a duplicate:
http://bugzilla.kernel.org/show_bug.cgi?id=13747

I get the same error attempting to load coretemp in 2.6.30.1 with a dual-core Atom N270 (supposedly) processor: "Unknown CPU model 1c".

Well it seems the patch was never applied to the upstream kernel :x

I wonder if that patch is safe for later kernels.........

I guess not.  I'd be nice if someone could update the patch (and get it into the kernel tree).

Rudolf Marek and myself are working on this right now:

http://lists.lm-sensors.org/pipermail/lm-sensors/2009-July/026263.html

We will attach the latest version of the patch to this bug soon. Please test it and report.

That patch seems to work.  Upon loading the patched coretemp module, dmesg tells me:
[220204.631910] coretemp coretemp.0: Using relative temperature scale!
[220204.631933] coretemp coretemp.0: Unable to read IA32_TEMPERATURE_TARGET MSR
[220204.633260] coretemp coretemp.1: Using relative temperature scale!
[220204.633286] coretemp coretemp.1: Unable to read IA32_TEMPERATURE_TARGET MSR

But I get correct-looking and appropriately changing temperature readouts for both processor cores.

Which patch did you test exactly? Rudolf sent an updated patch:

http://lists.lm-sensors.org/pipermail/lm-sensors/2009-July/026271.html

and there should be another update soon.

I'd tried the patch linked to at the url you posted before.  I just tried the more recent one, which doesn't output any warnings, and also seems to work.

However, the thermal driver still creates a thermal zone which is always 27°C.

The thermal driver is an ACPI thing, it has nothing to do with the coretemp driver. If ACPI reports a bogus temperature, you either have to get it fixed, or ignore it (blacklisting the thermal driver may or may not work depending on your distribution, and may or may not be a good idea depending on your BIOS implementation.)

Any news on a new patch from Rudolf?  Maybe something that works with 2.6.31?

Patch merged:
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=708a62bcd5f699756bae81491e64648fbf19e2a4

coretemp doesn't work (again?) with Intel Atom N280. 

Hardware Environment: 
Acer Aspire One AOD250-1613

lspci, lsmod, acpidump, and sensors-detect: http://drop.io/j3clgnv

uname -a: 
Linux aod250 2.6.31-ARCH #1 SMP PREEMPT Tue Nov 10 19:48:17 CET 2009 i686 Intel(R) Atom(TM) CPU N280 @ 1.66GHz GenuineIntel GNU/Linux

Problem Description:
drivers/hwmon/coretemp.c doesn't support Intel Atom N280 in Acer AOD250-1613

Error message:
* modprobe: FATAL: Error inserting coretemp (/lib/modules/2.6.31-ARCH/kernel/drivers/hwmon/coretemp.ko): No such device
* dmesg: coretemp: Unknown CPU model 1c
coretemp: Unknown CPU model 1c

Support for the Atom went in kernel 2.6.32, you're running 2.6.31. No surprise it doesn't work. If you really want support, you have to backport the 2.6.32 coretemp driver to your 2.6.31 kernel.

I grabbed 2.6.32's coretemp, diffed with 2.6.31, changed it as necessary, compiled and inserted to 2.6.31 Was modprobed just fine. 

lm-sensors now shows a temperature; the problem is... it's the hdd's temperature (confirmed thru booting to windows and checking with hwmon), not the cpu's. the cpu is supposed to be around 50C; the reported temp is same as hdd's average temp of 40C. 

output from sensors (ignore 27C at the buttom):

coretemp-isa-0000
Adapter: ISA adapter
Core 0:      +42.0°C  (crit = +90.0°C)                  

coretemp-isa-0001
Adapter: ISA adapter
Core 1:      +41.0°C  (crit = +90.0°C)                  

acpitz-virtual-0
Adapter: Virtual device
temp1:       +26.8°C  (crit = +100.0°C)

Unless I did some very funky thing with how i compiled coretemp (to have it look precisely at hdd temp and report it twice, as if it were a hyperthreaded atom cpu), things aren't working out for me :) See my comment #23 for hardware info (hoping drop.io is ok here). Thanks.

As far as I can tell, 2.6.32's coretemp module supports atom sensors by default.  I could be wrong.  My sensors also idle around 40C, though.  I've noticed that they jump up quickly in times of high CPU activity and drop right down again when the work is done (unless they're going for a while, in which case they take some time to cool down).

How did you check that those were the hard drive sensors via Windows?

> How did you check that those were the hard drive sensors via Windows?

I used the following in Windows: http://www.cpuid.com/hwmonitor.php

It shows 
1. acpi temp (the now-famous 27C, perhaps it gets it from weather.com)
2. Atom core temp (usually around 50C-57C, never went down to 40Cs, was 50-52C in idle)
3. Hdd temp (usually around 35-45C, never went up to 50Cs, was around 36C in idle)
4. battery info (charge stuff)

Basically, wondering whether hwmonitor shows battery voltages (I'm having problems with it), I noted my cpu temperature (I always look at it from time to time) in linux and booted promptly to windows. When I opened up hwmonitor, to my surprise, the temperature I noted (and monitored for a good 2 hours) in linux was shown as hdd temp. I worked on the lappy, trying to stress the cpu a little, then let it go idle for a long period, to make sure what I noted as cpu temp was hdd temp there... Cpu temp never went down under 48C or so (when idle for prolongued time period) according to hwmonitor under windows, while, right now, sensors report it to be 36C (steady). 

I looked up intel's specs for this cpu, and its maximum seems 90C. Accordingly, i would expect its fans to kick in after 50C or so. Right now, it's 36C (pretty much idle) and its fans are up and going. 

As a side note, there is definitely a corrolation between hdd temp and cpu temp. fans stop working when hdd temp goes below (and equal) 35C and kick up afterwards. Around 45C (hdd temp again), they go up a notch. This behavior seems in line with the specifications of my hdd (WD1600BEVT-22ZCT0): Western Digital says its operating temperature is up to 60C ( http://www.westerndigital.com/en/products/products.asp?driveid=513 ).

I'm clueless about hardware, but perhaps cpu's temperature affects hdd's? This is a small thing after all, and I expect the two (cpu & hdd) to be somewhat close to each other physically. 

Please let me know what else I can do to help :)

I now have 2.6.32 installed, coretemp still sees hdd temp as cpu temp as far as I can tell (~40C). should I open a new bug report? 

2.6.32-ARCH #1 SMP PREEMPT Sat Dec 26 08:26:17 UTC 2009 i686 Intel(R) Atom(TM) CPU N280 @ 1.66GHz GenuineIntel GNU/Linux

modinfo: 
filename:       /lib/modules/2.6.32-ARCH/kernel/drivers/hwmon/coretemp.ko
license:        GPL
description:    Intel Core temperature monitor
author:         Rudolf Marek <r.marek@assembler.cz>
depends:        
vermagic:       2.6.32-ARCH SMP preempt mod_unload 686

Please, stop spamming this bug entry. Support for the Intel Atom is in 2.6.32 and it's working. How thermal management is done on your specific laptop is a totally different issue. And it most certainly doesn't deserve an entry in bugzilla. The lm-sensors mailing list is the right place to discuss this kind of thing.

vajorie: If you think the wrong sensors' temperatures are being reported (or the temperature's being misreported, etc), I think one other more appropriate place to discuss it would be to open a new bug under Atom temperature support.  This bug here has the wrong topic and has the wrong people [still] assigned to it at this point for what you're trying to report.

If you do decide to open a new bug, could you CC me to it?  If you are indeed right about this, then my temperature's being misreported too, and I might be able to help debug.  Even if you're not, I'll be interested to see what's going on.