Re: PATCH: Allow user to force 'tsc' to be treated as stable.

From: Ben Greear
Date: Fri Feb 06 2009 - 12:52:34 EST


Jiri Kosina wrote:
On Thu, 5 Feb 2009, Ben Greear wrote:

Allow user to force TSC as stable clock-source. Works around BIOS issues in the FWA-7304 (Via CN700 chipset) system, and possibly others.

How do you know that the TSC is stable on such system? What was the reason for kernel marking it unstable?

I've used it for a timing source in my own modules and it has
worked well. It could still be broken in some way, but if so,
I'm not sure how to detect it. Ingo sent me a program to test
the tsc, and at least for short runs, it showed no problem.

Another person suggested the system might think it is unstable
because I have ACPI disabled in my BIOS and that might cause
the kernel not to have a 'PM timer' that it uses to check the
tsc?

Other than that, I have no idea why the kernel thinks the tsc
is unstable.

Thanks,
Ben

--
Ben Greear <greearb@xxxxxxxxxxxxxxx>
Candela Technologies Inc http://www.candelatech.com

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