cvs commit: src/sys/i386/cpufreq est.c

[Renato Botelho]

On Mon, Aug 25, 2008 at 5:21 PM, Dimitry Andric <dimitry at andric.com> wrote:

> On 2008-08-25 21:27, Renato Botelho wrote:
> > cpu0: <ACPI CPU> on acpi0
> > est0: <Enhanced SpeedStep Frequency Control> on cpu0
> > est0: Guessed bus clock (high) of 200 MHz
> >
> > Fatal trap 18: integer divide fault while in kernel mode
> > cpuid = 0; acpi id = 00
> > ...
> > panic: integer divide fault
>
> Unfortunately, there are CPU models around that have MSR_PERF_STATUS
> bits that are inconsistent, e.g:
>
> - The low and high multipliers (bits 31:24 and 15:8) are equal, so if
>  you subtract them and then divide... boom :)
> - Either the low or high multipliers (or both) are zero, which is also
>  not good, at least not with the current code.
>
> As an example, I originally added some multiplier sanity checks here:
> http://www.openbsd.org/cgi-bin/cvsweb/src/sys/arch/i386/i386/est.c#rev1.27
>
>
John,

Is this information good enough or you still need I collect some data? I'm
just
asking because i don't have a serial console at this machine and it's not so
easy
to get this kind of data.

Thanks
-- 
Renato Botelho