Re: [ACPI] _PDC method in DSDT

Ducrot Bruno
2003-06-23T16:11:36Z

On Mon, Jun 23, 2003 at 03:38:34PM +0200, Dominik Brodowski wrote:
> On Mon, Jun 23, 2003 at 02:19:27AM -0700, Grover, Andrew wrote:
> > The spec intended FixedFunctionalHW registers to be an "escape hatch".
> > FFH means that while ACPI is used for perf state enumeration, the
> > transitions will be handled in a CPU-specific driver, not via methods
> > described in the ACPI spec. This division (use ACPI for enum, x for
> > control) isn't currently supported by cpufreq; ACPI either does both
> > enum and control, or neither.
>
> But it could easily be added to the cpufreq drivers. For example, the
> speedstep-centrino driver could call a
>
> int acpi_get_frequency_table(struct cpufreq_frequency_table **freq_table)
>
> which returns an array with the frequency in freq_table[i].frequency, and
> some sort of "index" in freq_table[i].index, e.g. what needs to be written
> into the IA32_PERF_CTL MSR.
>

Yes. It can be added. But do we want to add it? That's the real
question.

--
Ducrot Bruno

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