From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Moore Subject: _PDC method in DSDT Date: 22 Jun 2003 17:45:31 -0700 Sender: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Message-ID: <1056329130.10322.36.camel@aldebaran.caltech.edu> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Return-path: Errors-To: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Help: List-Post: List-Subscribe: , List-Unsubscribe: , List-Archive: To: acpi-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: linux-acpi@vger.kernel.org Hi, Does anyone know the purpose or specification of the _PDC method of the DSDT? It's a reserved method that exists on my laptop (a Dell Latitude D600) but does not seem to be documented in the ACPI specification on the web. The reason I ask is that I'm interested in porting the cpufreq driver for Enhanced Speedstep to ACPI. Right now, the cpufreq driver has the tables of proper MSR register values encoded into the source, but a more elegant solution would be to get this information from ACPI. In my DSDT source I notice that when the _PDC method is called properly, the _PCT method will return FixedHardware addresses for the Enhanced Speedstep MSRs instead of its normal SystemIO ports. To get this to work on more than just my system, I should probably use the proper specification for calling _PDC rather than just making it work. Anyone have any suggestions? Regards, David ------------------------------------------------------- This SF.Net email is sponsored by: INetU Attention Web Developers & Consultants: Become An INetU Hosting Partner. Refer Dedicated Servers. We Manage Them. You Get 10% Monthly Commission! INetU Dedicated Managed Hosting http://www.inetu.net/partner/index.php