On Friday, August 10, 2007 11:37 AM, Mark.Haywood at Sun.COM wrote:

> Li, Aubrey wrote:
>> On Friday, August 10, 2007 10:55 AM, Dana.Myers at Sun.COM wrote:
>> 
>>> Li, Aubrey wrote:
>>>> On Friday, August 10, 2007 4:42 AM, Dana.Myers at Sun.COM wrote:
>>>> 
>>>>> Aubrey wrote:
>>>>> 
>>>>>> For P-state driver, I have one suggestion. There are still some
>>>>>> old machines which support early ACPI specs but not support
>>>>>> P-state. We should not ignore this kind of machine. So IMHO
>>>>>> P-state driver should check the version of ACPI and doesn't make
>>>>>> unnecessary warning.
>>>>> It's a bit difficult to tell what version of ACPI a BIOS has been
>>>>> "written for"; there's no version stamp on a BIOS saying
>>>>> "compliant with ACPI version x.xx".  Certainly we shouldn't
>>>>> generate warnings when a feature simply isn't supported, though.
>>>> Well, there is a structure member "Revision" in the RSDP structure.
>>>> The ACPI version 1.0 revision number of this table is zero. Later
>>>> the value for this field is 2. That's enough for PSS object
>>>> checking. I'll come up with a patch against it if it's acceptable.
>>> That field is the revision of the RSDP structure itself, not
>>> of the ACPI
>>> tables.
>>> It's been '2' in both the ACPI 2.x and 3.x specs and '0' in
>>> the 1.x spec,
>>> so I suppose we could infer from it that a BIOS written in the
>>> pre-2.0 era is present,  but I'm afraid I don't understand the
>>> exact error case we're
>>> discussing in the first place.  What is the problem we're
>>> trying to solve?
>>> I'd prefer to solve the root-cause of the problem rather use the
>>> RSDP structure version in a way not intended by the spec.
>>> 
>> 
>> I think it's PSS object not found. I checked ACPI spec and found PSS
>> object is introduced since ACPI2.0.
> 
> Right. In cpu_acpi.c we try to evaluate the _PSS object and
> AcpiEvaluateObjectTyped() fails to evaluate it because the _PSS is not
> there. This results in a call to cmn_err(). As I said previously, this
> messages is being displayed on the console. A bug was filed
> against this
> a couple of days ago:
> 
> 6589662 Error messages from cpu_acpi on install boot w/snv_70
> 
> I'm changing the behavior so that the message only gets logged to the
> system log. I'm not sure that I see a reason for checking the version
> and I'm not if there is a reliable way to do this. I didn't
> believe that
> it was the case that a BIOS implemented a specific ACPI version.
> 
> Regardless, we're going to want to log a message saying that we can't
> manage the P-states because we don't have a _PSS object (for whatever
> reason). 

OK, that makes sense to me.

Thanks,
-Aubrey
> 
>> So the machine wih ACPI1.0 don't have this object.
>> IMHO, that means speedstep driver would only work on the machines
>> with ACPI2.0 and later. So, for those ACPI1.0 machine, PSS warning
>> message is not necessary. But I need some time to verify the root
>> cause. 
>> 
>>>>> What version did you find on the Intel website?  We're
>>>>> currently at 20060721 in Solaris Nevada.
>>>>> 
>>>>> Dana
>>>> The current version is 20061109, here is the changelog.
>>>> http://www.intel.com/technology/iapc/acpi/downloads/changes.txt
>>>> I'm new to solaris, just want to know when and how this package is
>>>> updated into solaris.
>>> Thanks; we currently have a later source drop in-house, but there's
>>> an issue in 20070508 and later which results in a dead-lock when
>>> delivering GPE events. Do you know when Bob Moore will be back from
>>> sabbatical? 
>> 
>> Sorry, I have no idea, ;-)
>> 
>> Best Regards,
>> -Aubrey
>> Intel OpenSolaris Team
>> _______________________________________________
>> tesla-dev mailing list
>> tesla-dev at opensolaris.org
>> http://mail.opensolaris.org/mailman/listinfo/tesla-dev

Reply via email to