lkml.org 
[lkml]   [2005]   [Mar]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: PowerNow-K8 and Winchester CPUs
Hi!

Paul, can you comment on this one? I know that pn-k8 logic is quite
tricky... And BIOS tables are often wrong.
Pavel

> I have a machine with an Athlon64 with a Winchester core. It has a max
> frequency of 2GHz, vid 0x6. The maximum vid allowed is 0x4. It has an
> intermediate vid 0x8. RVO is 3.
>
> When transitioning (phase1) from vid 0x8 to vid 0x6, it first increases
> the vid to 6, and then proceeds increasing it three more steps. This of
> course fails, because it overflows the maximum allowed vid 0x4.
>
> My first attempt to fix this was to limit the vid to the max vid while
> doing the rvo bump-up.
>
> However, I believe that the real reason for the problem is that the
> condition to start doing the rvo bump is wrong.
>
> This patch should fix it:
>
> diff -Nru a/arch/i386/kernel/cpu/cpufreq/powernow-k8.c b/arch/i386/kernel/cpu/cpufreq/powernow-k8.c
> --- a/arch/i386/kernel/cpu/cpufreq/powernow-k8.c 2005-03-14 17:20:17 +01:00
> +++ b/arch/i386/kernel/cpu/cpufreq/powernow-k8.c 2005-03-14 17:20:17 +01:00
> @@ -286,7 +286,7 @@
> return 1;
> }
>
> - while ((rvosteps > 0) && ((data->rvo + data->currvid) > reqvid)) {
> + while ((rvosteps > 0) && ((data->currvid - data->rvo) > reqvid)) {
> if (data->currvid == 0) {
> rvosteps = 0;
> } else {
>
> if I understand the original intent of the second test in the while()
> statement.
>
> Any comments? Is my understanding of that bit of code correct?
>

--
People were complaining that M$ turns users into beta-testers...
...jr ghea gurz vagb qrirybcref, naq gurl frrz gb yvxr vg gung jnl!
-
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/

\
 
 \ /
  Last update: 2005-03-22 14:11    [W:0.089 / U:0.840 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site