Re: kernel won't boot on a Cyrix MediaGXm (Geode )

Juergen Beisert
2008-08-20T09:44:27Z

On Mittwoch, 20. August 2008, Ingo Molnar wrote:
> * Samuel Sieb <samuel@sieb.net> wrote:
> > Ingo Molnar wrote:
> >> any patch we should pick up to make your box boot?
> >
> > I've looked through various datasheets and found that the GXm and GXLV
> > Geode processors don't have an incrementor. I attached two patches. One
> > only calls the incrementor setup for GX1 or better. The other one
> > removes the incrementor setup entirely. As the incrementor value
> > differs according to clock speed and we would hope that the BIOS
> > configures it correctly, it is probably the better one to choose. But I
> > will leave that choice up to you. Either one works for me. :-)
>
> i went for the commit below and queued it up in tip/x86/urgent - thanks
> Samuel.
>
> what happens if the incrementor is not set up correctly by the BIOS

The system can freeze. The clock the incrementor modifies is used for the
external SDRAM (something like a delay line or jitter reduction). Thats why
its setting depends on the core clock speed.

Juergen
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