cpufreq change appears to cause ps2 mouse hangs

cpufreq change appears to cause ps2 mouse hangs

[Eric Oosting]

I wanted to bring a problem I am having to your
attention in hopes that
you might be able to help me correct my problem.

I have a dell latitude C600 laptop with a PIII 1Ghz
proc running the
latest Ubuntu (5.04) release and 2.6.10. Ubuntu uses
powernowd to adjust
frequency scaling.

My problem is that whenever powernowd changes the
frequency on my cpu my
mouse hangs for about a second with the following
error to
/var/log/messages:

Apr 22 20:58:44 localhost kernel: psmouse.c: TouchPad
at isa0060/serio1/input0 lost synchronization,
throwing 4 bytes away.
Apr 22 20:58:44 localhost kernel: psmouse.c: TouchPad
at isa0060/serio1/input0 lost sync at byte 1
Apr 22 20:58:44 localhost kernel: psmouse.c: TouchPad
at isa0060/serio1/input0 lost sync at byte 1
Apr 22 20:58:44 localhost kernel: psmouse.c: TouchPad
at isa0060/serio1/input0 - driver resynched.
Apr 22 21:06:34 localhost kernel: psmouse.c: TouchPad
at isa0060/serio1/input0 lost synchronization,
throwing 1 bytes away.
Apr 22 21:06:34 localhost kernel: psmouse.c: TouchPad
at isa0060/serio1/input0 lost sync at byte 1

This also happens if I have a standard USB mouse
plugged in. If I disable
powernowd I don't get any hickups. I don't believe the
problem is directly
because of powernowd because I am able to reproduce
the problem by running
"echo 700000 >
/sys/device/system/cpu/cpu0/cpufreq/scaling_setspeed"
or
setting it back to 1000000.   

Have you any ideas on how I might solve or mitigate
the problems I am
having? The cpu frequency scaling capabilities of the
2.6 kernel are
wonderful and I would much prefer to fix the problem
then disable any
tools that would change the scaling dynamically.

Thanks,
Eric


__________________________________________________
Do You Yahoo!?
Tired of spam?  Yahoo! Mail has the best spam protection around 
http://mail.yahoo.com 

Re: cpufreq change appears to cause ps2 mouse hangs

[Dmitry Torokhov]

On 4/25/05, Eric Oosting <eoosting@yahoo.com> wrote:
> 
> My problem is that whenever powernowd changes the
> frequency on my cpu my
> mouse hangs for about a second with the following
> error to
> /var/log/messages:
> 
> Apr 22 20:58:44 localhost kernel: psmouse.c: TouchPad
> at isa0060/serio1/input0 lost synchronization,
> throwing 4 bytes away.

I don't think it is cpufreq that is to blame, but rather because (I am
speculating here) powernowd reads /proc/acpi/battery/BATX/info which
is known to take a _long_ time and mess up KBC...

Do you see the same messages if you switch frequency directly through
sysfs without powernowd involved?

-- 
Dmitry

Re: cpufreq change appears to cause ps2 mouse hangs

[Bruno Ducrot]

On Mon, Apr 25, 2005 at 12:04:59PM -0700, Eric Oosting wrote:
> I wanted to bring a problem I am having to your
> attention in hopes that
> you might be able to help me correct my problem.
> 
> I have a dell latitude C600 laptop with a PIII 1Ghz
> proc running the
> latest Ubuntu (5.04) release and 2.6.10. Ubuntu uses
> powernowd to adjust
> frequency scaling.
> 
> My problem is that whenever powernowd changes the
> frequency on my cpu my
> mouse hangs for about a second with the following
> error to
> /var/log/messages:
> 
> Apr 22 20:58:44 localhost kernel: psmouse.c: TouchPad
> at isa0060/serio1/input0 lost synchronization,
> throwing 4 bytes away.
> Apr 22 20:58:44 localhost kernel: psmouse.c: TouchPad
> at isa0060/serio1/input0 lost sync at byte 1
> Apr 22 20:58:44 localhost kernel: psmouse.c: TouchPad
> at isa0060/serio1/input0 lost sync at byte 1
> Apr 22 20:58:44 localhost kernel: psmouse.c: TouchPad
> at isa0060/serio1/input0 - driver resynched.
> Apr 22 21:06:34 localhost kernel: psmouse.c: TouchPad
> at isa0060/serio1/input0 lost synchronization,
> throwing 1 bytes away.
> Apr 22 21:06:34 localhost kernel: psmouse.c: TouchPad
> at isa0060/serio1/input0 lost sync at byte 1
> 
> This also happens if I have a standard USB mouse
> plugged in. If I disable
> powernowd I don't get any hickups. I don't believe the
> problem is directly
> because of powernowd because I am able to reproduce
> the problem by running
> "echo 700000 >
> /sys/device/system/cpu/cpu0/cpufreq/scaling_setspeed"
> or
> setting it back to 1000000.   
> 
> Have you any ideas on how I might solve or mitigate
> the problems I am
> having? The cpu frequency scaling capabilities of the
> 2.6 kernel are
> wonderful and I would much prefer to fix the problem
> then disable any
> tools that would change the scaling dynamically.
> 

What cpufreq driver are you using (speedstep-ich, speedstep-smi)?
What kind of southbridge (ich or piix4 or whatever)?
Could you post a dmesg and a lspci -v?
Also have you the same problem but without ACPI? (I suspect actually
a problem with the power state, a cat /proc/acpi/processor/*/power may
help also)

Cheers,

-- 
Bruno Ducrot

--  Which is worse:  ignorance or apathy?
--  Don't know.  Don't care.