PROBLEM: Enabling CPU freq scaling on VIA Cyrix 3 causes kernel l ockup / divide error

PROBLEM: Enabling CPU freq scaling on VIA Cyrix 3 causes kernel l ockup / divide error

[Hassard, Stephen]

System: VIA Epia 800 Motherboard w/ VIA C3 Processor @ 800 MHz.

Kernel: 2.6.0-test1

Problem: When I enable CPUFreq scaling with longhaul, the kernel crashes on
startup with the following error:

>>
longhaul: VIA CPU detected. Longhaul version 2 supportred
longhaul: VRM 8.5 : Min VID=1.250 Max VID=1.250, 0 possible voltage scales
longhaul: MinMult(x10)=30 MaxMult(x10)=60
longhaul: Lowestspeed=0 Highestspeed=0
longhaul: FSB:0 Mult(x10):100
divide error: 0000 [#1]
CPU:    0
<<

Thanks,
Stephen Hassard

Re: PROBLEM: Enabling CPU freq scaling on VIA Cyrix 3 causes kernel l ockup / divide error

[Dave Jones]

On Mon, Jul 14, 2003 at 08:46:19AM -0700, Hassard, Stephen wrote:
 > longhaul: VIA CPU detected. Longhaul version 2 supportred
 > longhaul: VRM 8.5 : Min VID=1.250 Max VID=1.250, 0 possible voltage scales
                           ^^^^^^^^^^^^^^^^^^^^^^^

Erk, it should default into the 'voltage scaling unavailable' mode when
this happens, but the code is missing. I'll push that out to Linus
along with a large bunch of other cpufreq changes tonight/tomorrow.

Strange how your CPU seems to claim to support voltage scaling, but
erm.. doesn't. Can you also mail me the output of x86info -a -v
(Get the snapshot from http://www.codemonkey.org.uk/cvs/ )

 > longhaul: MinMult(x10)=30 MaxMult(x10)=60
 > longhaul: Lowestspeed=0 Highestspeed=0
 > longhaul: FSB:0 Mult(x10):100

Something also went horribly wrong when trying to determine your FSB.

 > divide error: 0000 [#1]

Leading to this tradegy. I'll take a look over the longhaul code later
too, as it could use some cleanups in more than a few areas.
I've also fallen behind in adding support for the newer C3s to it.

		Dave