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

From: Samuel Sieb
Date: Wed Jul 23 2008 - 03:14:47 EST

Juergen Beisert wrote:
On Dienstag, 22. Juli 2008, Samuel Sieb wrote:
Juergen Beisert wrote:
linux-2.6.25/arch/x86/kernel/cyrix.c, line 151. Disable this line or
change the value 0x04 according to the speed of your CPU. This tweak
helps others with random hangs of their system.
I tried various values and various combinations of commenting out lines
and the only one that worked for me was to comment out the PCR1 line
just above it. With that line commented out (or both of them), it

Hmm, then your BIOS does know more about your hardware than the kernel. ;-)
The PCR1 line enables the incrementor. If disabled the value in PCR0 doesn't matter.

I did some more testing and the end result is that you can't enable the incrementor on this cpu. I tried values from 0 to 7 for the PCR0 and it always crashed or hung (0 also gave noise all over the screen). The values set by the BIOS are PCR1: 1 and PCR0: 0.
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