Missing PSB or _PSS in BIOS

Missing PSB or _PSS in BIOS

[Vince]

Hello,

I'm using an opteron 165 (dual-core) which frequency/voltage should
be able to be scaled, but unfortunately the latest BIOS for my motherboard
lacks the frequency transition tables needed by powernow-k8.c

as shown by the boot message:
powernow-k8: MP systems not supported by PSB BIOS structure
powernow-k8:  BIOS error - no PSB or ACPI _PSS objects

Would it be possible to write suitable ACPI _PSS from AMD processor 
documentation ?
Or take the infos from some other ACPI BIOS which has support, and put 
it in mine ?

And use the "ACPI load custom DSDT" kernel option to get the patched one 
used by the
powernow-k8 driver ?

I found a lot of infos about fixing glitches in DSDT but could not find 
anything
about adding missing  _PSS entries...

Would that be dangerous ?

Is there something else I could do ?
I don't think I'll get an answer from the vendor, even if I tried...

Please, keep me on the CC list

-- 
Vincent Legoll

Re: Missing PSB or _PSS in BIOS

[Bruno Ducrot]

On Sun, Feb 19, 2006 at 02:45:06AM +0100, Vince wrote:
> Hello,
> 
> I'm using an opteron 165 (dual-core) which frequency/voltage should
> be able to be scaled, but unfortunately the latest BIOS for my motherboard
> lacks the frequency transition tables needed by powernow-k8.c
> 
> as shown by the boot message:
> powernow-k8: MP systems not supported by PSB BIOS structure
> powernow-k8:  BIOS error - no PSB or ACPI _PSS objects
> 
> Would it be possible to write suitable ACPI _PSS from AMD processor 
> documentation ?
> Or take the infos from some other ACPI BIOS which has support, and put 
> it in mine ?
> 
> And use the "ACPI load custom DSDT" kernel option to get the patched one 
> used by the
> powernow-k8 driver ?
> 
> I found a lot of infos about fixing glitches in DSDT but could not find 
> anything
> about adding missing  _PSS entries...
> 
> Would that be dangerous ?
> 
> Is there something else I could do ?
> I don't think I'll get an answer from the vendor, even if I tried...
> 

First, check if 'Cool'n Quiet' is enabled in the bios.  Second, if that
do not work, try to upgrade your bios.  I had a similar problem with a
HP Proliant 385, and after upgrading it was (almost) ok (they just
forgot one p-state, but it was easy to add it afterward).

-- 
Bruno Ducrot

--  Which is worse:  ignorance or apathy?
--  Don't know.  Don't care.

RE: Missing PSB or _PSS in BIOS

[Brown, Len]

>I'm using an opteron 165 (dual-core) which frequency/voltage should
>be able to be scaled, but unfortunately the latest BIOS for my 
>motherboard
>lacks the frequency transition tables needed by powernow-k8.c
>
>as shown by the boot message:
>powernow-k8: MP systems not supported by PSB BIOS structure
>powernow-k8:  BIOS error - no PSB or ACPI _PSS objects
>
>Would it be possible to write suitable ACPI _PSS from AMD processor 
>documentation ?
>Or take the infos from some other ACPI BIOS which has support, and put 
>it in mine ?
>
>And use the "ACPI load custom DSDT" kernel option to get the 
>patched one 
>used by the
>powernow-k8 driver ?
>
>I found a lot of infos about fixing glitches in DSDT but could 
>not find 
>anything
>about adding missing  _PSS entries...
>
>Would that be dangerous ?
>
>Is there something else I could do ?
>I don't think I'll get an answer from the vendor, even if I tried...

Sure it is possible.

It is only dangerous if you care about the data on the machine.
Presumably the vendor had a reason not to enable this feature...

-Len

Re: Missing PSB or _PSS in BIOS

[Vince]

Brown, Len wrote:
 >> I'm using an opteron 165 (dual-core) which frequency/voltage should
 >> be able to be scaled, but unfortunately the latest BIOS for my
 >> motherboard
 >> lacks the frequency transition tables needed by powernow-k8.c
 >>
 >> as shown by the boot message:
 >> powernow-k8: MP systems not supported by PSB BIOS structure
 >> powernow-k8:  BIOS error - no PSB or ACPI _PSS objects
 >>
 >> Would it be possible to write suitable ACPI _PSS from AMD processor
 >> documentation ?
 >> Or take the infos from some other ACPI BIOS which has support, and put
 >> it in mine ?
 >>
 >> And use the "ACPI load custom DSDT" kernel option to get the
 >> patched one
 >> used by the
 >> powernow-k8 driver ?
 >>
 >> I found a lot of infos about fixing glitches in DSDT but could
 >> not find
 >> anything
 >> about adding missing  _PSS entries...
 >>
 >> Would that be dangerous ?
 >>
 >> Is there something else I could do ?
 >> I don't think I'll get an answer from the vendor, even if I tried...
 >
 > Sure it is possible.

 > It is only dangerous if you care about the data on the machine.
 > Presumably the vendor had a reason not to enable this feature...

I suspected the reason would be 'do not care', but you are making it sound
this is not right for this processor, or something... Care to elaborate 
a bit,
or could you point me at a CPU errata or any other source of information
that will enlighten me as to why enabling this feature would eat my data...

The powernow driver has got patches to enable dual core CPUs, the CPU report
the feature as present (/proc/cpuinfo), so I had the impression this was not
working only because the BIOS is crappy, not because of it being a dangerous
feature...

Sorry if you think I'm silly, but I'm new to ACPI / powernow internals, 
so please,
excuse my ignorance...

-- 
Vincent Legoll