Issues with lm_sensors on Intel SE7501cw2

Marc Rieffel marc at paracel.com
Tue Oct 21 22:28:41 CEST 2003


Yes, pwmconfig seems to confirm the cross-connection of fans.  The output is below.  On this particular system max6650/fan1 is disconnected, which is correctly detected.  

It found that max6650/fan2 is controlled by w83627hf/pwm1, and that w83627hf/fan2 is controlled by w83627hf/pwm2, but it didn't detect that w83627hf/fan1 is also controlled by w83627hf/pwm2.  It may have gotten confused when the pwm setting was mysteriously modified by some other process (or the bios?).  

Also, the fancontrol file doesn't seem to reflect the configuration that it detected.

******************

[root at gb0007 lm_sensors-2.8.1]# prog/pwm/pwmconfig                              This program will search your sensors for pulse width modulation (pwm)
controls, and test each one to see if it controls a fan on
your motherboard. Note that many motherboards do not have pwm
circuitry installed, even if your sensor chip supports pwm.

We will attempt to briefly stop each fan using the pwm controls.
The program will attempt to restore each fan to full speed
after testing. However, it is ** very important ** that you
physically verify that the fans have been to full speed
after the program has completed.

Found the following PWM controls:
   w83627hf-isa-0290/pwm1
   w83627hf-isa-0290/pwm2

Found the following fan sensors:
   max6650-i2c-0-1b/fan1     current speed: 0 ... skipping!
   max6650-i2c-0-1b/fan2     current speed: 3510 RPM
   max6650-i2c-0-1b/fan3     current speed: 6570 RPM
   max6650-i2c-0-1b/fan4     current speed: 6330 RPM
   w83627hf-isa-0290/fan1     current speed: 3214 RPM
   w83627hf-isa-0290/fan2     current speed: 3183 RPM
   w83627hf-isa-0290/fan3     current speed: 3183 RPM

Warning!!! This program will stop your fans, one at a time,
for approximately 5 seconds each!!!
This may cause your processor temperature to rise!!!
If you do not want to do this hit control-C now!!!
Hit return to continue:

Testing pwm control w83627hf-isa-0290/pwm1 ...
  max6650-i2c-0-1b/fan2 ... speed was 3510 now 1680
    It appears that fan max6650-i2c-0-1b/fan2
    is controlled by pwm w83627hf-isa-0290/pwm1
    Would you like to generate a detailed correlation (y) ?
    PWM 255 FAN 3540
    PWM 240 FAN 3540
    PWM 225 FAN 3540
    PWM 210 FAN 3540
    PWM 195 FAN 3510
    PWM 180 FAN 3510
    PWM 165 FAN 3540
    PWM 150 FAN 3540
    PWM 135 FAN 3540
    PWM 120 FAN 3510
    PWM 105 FAN 3510
    PWM 90 FAN 3510
    PWM 75 FAN 3510
    PWM 60 FAN 3510
    PWM 45 FAN 3540
    PWM 30 FAN 3540
    PWM 15 FAN 3510
    PWM 0 FAN 2160

  max6650-i2c-0-1b/fan3 ... speed was 6570 now 6600
    no correlation
  max6650-i2c-0-1b/fan4 ... speed was 6330 now 6330
    no correlation
  w83627hf-isa-0290/fan1 ... speed was 3214 now 0
    It appears that fan w83627hf-isa-0290/fan1
    is controlled by pwm w83627hf-isa-0290/pwm1
    Fan w83627hf-isa-0290/fan1 has not returned to speed, please investigate!
  w83627hf-isa-0290/fan2 ... speed was 3183 now 0
    It appears that fan w83627hf-isa-0290/fan2
    is controlled by pwm w83627hf-isa-0290/pwm1
    Fan w83627hf-isa-0290/fan2 has not returned to speed, please investigate!
  w83627hf-isa-0290/fan3 ... speed was 3183 now 3183
    no correlation

Testing pwm control w83627hf-isa-0290/pwm2 ...
  max6650-i2c-0-1b/fan2 ... speed was 3510 now 3540
    no correlation
  max6650-i2c-0-1b/fan3 ... speed was 6570 now 6600
    no correlation
  max6650-i2c-0-1b/fan4 ... speed was 6330 now 6330
    no correlation
  w83627hf-isa-0290/fan1 ... speed was 3214 now 0
    It appears that fan w83627hf-isa-0290/fan1
    is controlled by pwm w83627hf-isa-0290/pwm2
    Fan w83627hf-isa-0290/fan1 has not returned to speed, please investigate!
  w83627hf-isa-0290/fan2 ... speed was 3183 now 0
    It appears that fan w83627hf-isa-0290/fan2
    is controlled by pwm w83627hf-isa-0290/pwm2
    Would you like to generate a detailed correlation (y) ?
    PWM 255 FAN 3169
    PWM 240 FAN 3169
    PWM 225 FAN 3169
    PWM 210 FAN 3276
    PWM 195 FAN 3183
    PWM 180 FAN 3169
    PWM 165 FAN 3169
    PWM 150 FAN 3169
    PWM 135 FAN 3260
    PWM 120 FAN 3276
    PWM 105 FAN 3169
    PWM 90 FAN 3169
    PWM 75 FAN 3154
    PWM 60 FAN 3169
    PWM 45 FAN 3169
    PWM 30 FAN 3245
    PWM 15 FAN 0
    Fan Stopped at PWM = 15

  w83627hf-isa-0290/fan3 ... speed was 3183 now 3245
    no correlation

Testing is complete.
Please verify that all fans have returned to their normal speed.

The fancontrol script can automatically respond to temperature changes
of your system by changing fanspeeds. Do you want to set up its
configuration file now? (y)

What should be the path to your fancontrol config file? (/etc/fancontrol)

Loading configuration from /etc/fancontrol ...

Select fan output to configure:
1) w83627hf-isa-0290/pwm2  6) Change INTERVAL
2) w83627hf-isa-0290/pwm2  7) Just quit
3) w83627hf-isa-0290/pwm1  8) Save and quit
4) w83627hf-isa-0290/pwm1  9) Show configuration
5) w83627hf-isa-0290/pwm1
#? 9

Common Settings:
INTERVAL=10

Settings of w83627hf-isa-0290/pwm2:
  Depends on
  MINTEMP=
  MAXTEMP=
  MINSTART=
  MINSTOP=

Settings of w83627hf-isa-0290/pwm2:
  Depends on
  MINTEMP=
  MAXTEMP=
  MINSTART=
  MINSTOP=

Settings of w83627hf-isa-0290/pwm1:
  Depends on
  MINTEMP=
  MAXTEMP=
  MINSTART=
  MINSTOP=

Settings of w83627hf-isa-0290/pwm1:
  Depends on
  MINTEMP=
  MAXTEMP=
  MINSTART=
  MINSTOP=

Settings of w83627hf-isa-0290/pwm1:
  Depends on
  MINTEMP=
  MAXTEMP=
  MINSTART=
  MINSTOP=

#? 8

Saving configuration to /etc/fancontrol...
Configuration saved

> -----Original Message-----
> From: Mark Studebaker [mailto:mds at paradyne.com]
> Sent: Monday, October 20, 2003 5:23 PM
> To: Marc Rieffel
> Cc: sensors at stimpy.netroedge.com; John Morris; Bob Y. Hsin
> Subject: Re: Issues with lm_sensors on Intel SE7501cw2
> 
> 
> one program that may be helpful for you is prog/pwm/pwmconfig.
> If it's working well it should confirm the motherboard setup
> you documented below, including the 'cross-connection'.
> 
> 
> Marc Rieffel wrote:
> > 
> > > > [root at gb0007 lm_sensors-2.8.1]# rmmod w83781d
> > >
> > > That module isn't supposed to be loaded at this moment. There's
> > > something unclear here, the rmmod command should return 
> an error. Can
> > > you test that again, checking with lsmod which modules 
> are loaded each
> > > time? Don't you have some kind of module auto-loading 
> making trouble
> > > here? Taking a look at dmesg while loading/unloading the 
> modules could
> > > help.
> > 
> > I tried this again and it worked normally.  With 83781d 
> loaded, I get nothing.  With w83627hf loaded, I see the 
> sensors.  Maybe I cut and pasted the wrong thing in my initial email.
> > 
> > >
> > > > 2. The max6650 fan speed measurement seems to be all or 
> nothing.  If
> > > > there's a (Sunon) fan connected and operational, it reports
> > > 7650RPM.
> > > > If there's no fan connected, it reports 0 RPM.  If I 
> physically slow
> > > > the fan down, it still report 7650 RPM.  (The tachs on 
> the w83627hf
> > > > sensor do show decreased rpm when I impede their fans).
> > 
> > Any thoughts on this?
> > 
> > > > 3. The fan speeds reported (7650 or 18,000-21,000) seem to be
> > > > inconsistent with the advertised speeds.  Changing the divisors
> > > > doesn't seem to affect the reported values.
> > 
> > Or this?
> > 
> > > > 4. The speed control on the max6650 doesn't seem to work.
> > > See below.
> > >
> > > Strange. Could be because the driver assumes too much 
> conditions that
> > > aren't correct for your system. The MAX6650 driver was 
> contributed by
> > > John Morris. John, could you please take a look at Mark's problem?
> > >
> > > > 5. The w83627hf's "pwm1" setting seems to have no effect:
> > >
> > > I think that PWM needs special wiring on the motherboad 
> in order to
> > > work. Could it be that your motherboard doesn't have it?
> > >
> > 
> > Well, I've figured out part of the answer to 4 & 5.  Here's 
> how my motherboard is set up.
> > 
> > Fan             Controlled by           Monitored by
> > J29/sys3        w83627hf pwm1           max6651 fan1
> > J30/sys4        w83627hf pwm1           max6651 fan2
> > J16/cpu1        n/a                             max6651 fan3
> > J14/cpu2        n/a                             max6651 fan4
> > J3/sys2 w83627hf pwm2           w83627hf fan1
> > J1/sys1 w83627hf pwm2           w83627hf fan2
> > J58/sys5        max6651 speed           w83627hf fan3
> > 
> > I can't begin to imagine why they have these chips 
> cross-connected, with one chip controlling a fan and a 
> different chip monitoring it.  The Winbond has two pwm's, 
> each controlling two fans, and it only operates in "open 
> loop" mode.  I read the max6651 data sheet 
> (http://pdfserv.maxim-ic.com/en/ds/MAX6650-MAX6651.pdf), and 
> it supports four modes, always on, always off, open loop (use 
> pwm to achieve a desired voltage), and closed loop (use pwm 
> to achieve a desired fan1 speed).  Reading the configuration 
> register from the driver suggests that it's in closed loop mode.
> > 
> > # cat /proc/sys/dev/sensors/max6650-i2c-0-1b/xdump
> > 38 42 255 0 0 0 31 2
> > 
> > Bits 5 and 4 of 42 are 1 and 0
> > 
> > The fact that changing the "speed" setting affects the 
> speed of the J58 fan suggests that it's actually operating in 
> "open loop" mode.  Given that it isn't wired to monitor the 
> fan that it's controlling, I would think there's no way that 
> it could run in closed loop mode.
> > 
> > Question: Am I interpreting the xdump values correctly?
> > 
> > Request: How about making the xdump values easier to 
> interpret, and making the configuration register writable in 
> software, so that I can try things like setting it to always-off mode?
> > 
> > > > 6. The w83627hf's "pwm2" setting is able to reduce the
> > > speed of fans 1
> > > > and 2, but only to about half.  I can hear them change
> > > speed when I do
> > > > this.  I can't get them to stop completely, though.
> > >
> > > This may be a feature more that a bug. Fully starting a 
> fan requires a
> > > higher current. What's more, stopping a fan completely is somewhat
> > > dangerous, isn't it? Same as for PWM1, I think that PWM2
> > > works thank to
> > > adequate wiring on your motherboard, but maybe the wiring and
> > > electronics are such that the W83627HF isn't allowed to 
> lower the fan
> > > speed below a given threshold.
> > 
> > The max6651 data sheet says something about how lowering 
> the PWM and therefore the voltage on the fan may result in 
> odd behavior, like the fan stopping completely or the tach 
> signal not reporting at all or reporting too many times.  I 
> suppose that makes sense.  That doesn't explain why setting 
> PWM to zero doesn't stop the fan, though.  If my observations 
> are consistent with those of others, and there's no real way 
> to stop the fans, I can live with that.  I don't really need 
> to stop the fans.  I'm just trying to understand what's going 
> on.  So far everything I've tried has given me a result 
> different from what I've expected, and that makes it hard for 
> me to have much confidence that the system is doing what I 
> think it is.
> > 
> > > > 7.  Changes to the "pwm2" setting seem to be transient. 
>  Something
> > > > happens to change it back to 255.
> > > >
> > > > [root at oscarnode001 root]# cat
> > > > /proc/sys/dev//sensors/w83627hf-isa-0290/pwm2     0 1
> > > > [root at oscarnode001 root]# sleep 60
> > > > [root at oscarnode001 root]# cat
> > > > /proc/sys/dev//sensors/w83627hf-isa-0290/pwm2     255 1
> > >
> > > Don't you by any chance have a monitoring daemon running on
> > > the machine?
> > 
> > I'm not aware of any, but RH9 may have installed something 
> that I don't know about.  How can I tell?  What are the names 
> of some monitoring daemons that I could check for?
> > 
> > >
> > > > 8. Sometimes the "lm75" module loads and detects 
> something.  I'm not
> > > > aware of there being any lm75's or compatible devices on
> > > this system.
> > > > (...)
> > > > 9. The lm75's temperature readings are bogus.  At an 
> earlier point I
> > > > got them to report reasonable values, but I can't get 
> back to that
> > > > state.
> > >
> > > Could you provide the output of "i2cdetect 0"? I'd also be
> > > interested in
> > > the output of "i2cdump 0 0x1f" since you seem to have an 
> unknown chip
> > > there.
> > >
> > 
> > ]# i2cdetect 0
> >   WARNING! This program can confuse your I2C bus, cause 
> data loss and worse!
> >   I will probe file /dev/i2c-0
> >   You have five seconds to reconsider and press CTRL-C!
> > 
> >      0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
> > 00: XX XX XX XX XX XX XX XX XX XX XX XX XX XX XX XX
> > 10: XX XX XX XX XX XX XX XX XX XX XX UU XX XX XX 1f
> > 20: XX XX XX XX XX XX XX XX XX XX XX XX XX XX XX XX
> > 30: 30 31 XX XX 34 35 XX XX XX XX XX XX XX XX XX XX
> > 40: XX XX XX XX XX XX XX XX XX XX XX XX XX XX XX XX
> > 50: UU UU XX XX UU UU XX XX XX XX XX XX XX XX XX XX
> > 60: XX XX XX XX XX XX XX XX XX 69 XX XX XX XX XX XX
> > 70: XX XX XX XX XX XX XX XX XX XX XX XX XX XX XX XX
> > 
> > > Strangely, sensors-detect didn't report any client found at these
> > > addresses (0x48 and 0x49). Could you run sensors-detect 
> again (unload
> > > all client drivers first) and see if it now does? These 
> LM75s could
> > > actually be emulated by your w83627hf, although it's unusual
> > > to see this
> > > behavior when the w83627hf itself is on the ISA (as opposed
> > > to I2C) bus.
> > >
> > 
> > I tried it again.  No lm75's.  Output below.
> > 
> > > > 10.  The default value for the sensor type on the  w83627hf's
> > > > temperature sensor, according to sensors.conf, is
> > > thermistor (3435).
> > > > But for me it seems to be defaulting to "1", PII/Celeron Diode.
> > >
> > > The "defaults" might be confusing, I agree. This refers 
> to power-up
> > > default for the chip. The BIOS may then reconfigure the chip
> > > during the
> > > boot process. I believe that this is what has happened there.
> > >
> > > If you believe that we should say the things differently in the
> > > configuration file, suggestions are welcome.
> > 
> > It would be helpful if you included your clarification 
> about chip vs. bios defaults.
> > 
> > >
> > > Thanks for the long and detailed report. I doubt we'll be able to
> > > quickly solve all the problems you encountered, since 
> there are many,
> > > still this will help us if similar problems are reported in
> > > the future,
> > > plus I hope I clarified some points.
> > 
> > Thanks for your help.
> > 
> > This whole thing has turned out to be much more complicated 
> and difficult than I would have expected.  I've been at it 
> for over a week now, with thermometers, multimeters, 
> oscilliscopes, duct tape and bailing wire.  I finally have 
> the temperature information I want, and I can tell if my fans 
> are running or not, but I'm still not sure if sensors is 
> reporting the correct fan speed.
> > 
> > On the positive side, when I first tried lm_sensors a year 
> or two ago, I got absolutely nowhere, so it's obviously come 
> a long way since then.  Keep up the good work!
> >
> 



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