Re: [ACPI] _PDC method in DSDT

Dominik Brodowski
2003-06-23T13:42:43Z

On Mon, Jun 23, 2003 at 12:53:27AM -0700, David Moore wrote:
> My intention was not for processor.c and cpufreq to cooperate, but
> rather for processor.c to be able to control Enhanced Speedstep solely
> with P-states -- no cpufreq necessary. Cpufreq is certainly useful for
> those systems not running the ACPI driver, but in the long run, ACPI and
> processor.c seem to be the right way to get maximum compatibility with
> many platforms.

Actually, in 2.5. ACPI provides one of several cpufreq drivers. The user can
choose which one best suits his needs [e.g. speedstep-centrino for the
faster wrmsr method instead of the slow io-based ACPI-2.0 module -
arch/i386/cpu/cpufreq]. Also I doubt that ACPI will allow maximum
compatibility: this new _PCT method again tries to implement things
in a "proprietary", "legacy", "secret" way, supported only by
reverse-engineered or binary-only drivers.

Dominik