Re: 2.4.19-pre10-ac1: Hardcoded cpu_khz in powernow-k6.c

Dave Jones (davej@suse.de)
Wed, 5 Jun 2002 03:02:23 +0200


On Wed, Jun 05, 2002 at 02:52:15AM +0200, Adrian Bunk wrote:
> Hi Dave,
>
> while reading through powernow-k6.c in 2.4.19-pre10-ac1 I found the
> following that seems to be a bug:
>
> static unsigned long cpu_khz=350000;
>
> Not every K6-2/3 runs at 350 MHz...

iirc, there aren't any MSRs[*] on the K6-2 where we can read
the current FSB. I think 350MHz was used as it was probably
the slowest K6-2 to be found at the time. You can override
it with boot time arguments.

Dave.

[*] The K6 style powernow was reverse engineered, as there were
no publically available documents explaining it. All we can
do is scale multipliers. No voltage scaling, no FSB decoding.

-- 
| Dave Jones.        http://www.codemonkey.org.uk
| SuSE Labs
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/