From owner-freebsd-acpi@FreeBSD.ORG Wed Feb 3 14:53:17 2010 Return-Path: Delivered-To: freebsd-acpi@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 9BCE31065679; Wed, 3 Feb 2010 14:53:17 +0000 (UTC) (envelope-from avg@icyb.net.ua) Received: from citadel.icyb.net.ua (citadel.icyb.net.ua [212.40.38.140]) by mx1.freebsd.org (Postfix) with ESMTP id 69DC08FC12; Wed, 3 Feb 2010 14:53:15 +0000 (UTC) Received: from odyssey.starpoint.kiev.ua (alpha-e.starpoint.kiev.ua [212.40.38.101]) by citadel.icyb.net.ua (8.8.8p3/ICyb-2.3exp) with ESMTP id QAA08273; Wed, 03 Feb 2010 16:53:13 +0200 (EET) (envelope-from avg@icyb.net.ua) Message-ID: <4B698DD8.4010404@icyb.net.ua> Date: Wed, 03 Feb 2010 16:53:12 +0200 From: Andriy Gapon User-Agent: Thunderbird 2.0.0.23 (X11/20091206) MIME-Version: 1.0 To: freebsd-acpi@FreeBSD.org X-Enigmail-Version: 0.95.7 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Cc: Rui Paulo , John Baldwin Subject: acpi_cpu: _PDC vs _OSC X-BeenThere: freebsd-acpi@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: ACPI and power management development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 03 Feb 2010 14:53:17 -0000 What do you think about changing logic of evaluating _PDC and _OSC for Processor object in acpi_cpu_attach? It seems that later versions of ACPI standard deprecate _PDC in favor of _OSC. Although, in practice they seem to be present or not present together, sometimes _PDC being only a wrappper around _OSC. There are still, of course, systems with only _PDC present. I assume that there are systems with only _OSC too. I would like to change the order, so that _OSC evaluation is attempted first and only if it fails then proceed with _PDC. Also, I would like to print status returned by _OSC (in case of successful evaluation) if it is not zero. (Note: this is not the same as status of evaluating _OSC). And I am going to fix the following comment: * On some systems we need to evaluate _OSC so that the ASL * loads the _PSS and/or _PDC methods at runtime. Although on many systems either _PDC or _OSC or both dynamically load SSDTs that contain additional Processor objects like _PSS and _PCT, I haven't seen any system where _OSC would load _PDC. And, honestly, that wouldn't make any sense. Perhaps, comment's author meant _PCT in place of _PDC, or something like that. Please let me know what you think. Thanks! Convenience link: http://download.intel.com/technology/IAPC/acpi/downloads/30222305.pdf -- Andriy Gapon