From owner-freebsd-acpi@FreeBSD.ORG  Thu Feb  4 22:13:33 2010
Return-Path: <owner-freebsd-acpi@FreeBSD.ORG>
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 BC4A0106566C;
	Thu,  4 Feb 2010 22:13:33 +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 95F938FC18;
	Thu,  4 Feb 2010 22:13:32 +0000 (UTC)
Received: from porto.topspin.kiev.ua (porto-e.starpoint.kiev.ua
	[212.40.38.100])
	by citadel.icyb.net.ua (8.8.8p3/ICyb-2.3exp) with ESMTP id AAA02026;
	Fri, 05 Feb 2010 00:13:31 +0200 (EET) (envelope-from avg@icyb.net.ua)
Received: from localhost.topspin.kiev.ua ([127.0.0.1])
	by porto.topspin.kiev.ua with esmtp (Exim 4.34 (FreeBSD))
	id 1Nd9x4-0004KK-SM; Fri, 05 Feb 2010 00:13:30 +0200
Message-ID: <4B6B4689.4020708@icyb.net.ua>
Date: Fri, 05 Feb 2010 00:13:29 +0200
From: Andriy Gapon <avg@icyb.net.ua>
User-Agent: Thunderbird 2.0.0.23 (X11/20091128)
MIME-Version: 1.0
To: John Baldwin <jhb@freebsd.org>
References: <4B698DD8.4010404@icyb.net.ua> <4B69E0BA.4080104@root.org>
	<4B6B2337.8070404@icyb.net.ua> <201002041657.52232.jhb@freebsd.org>
In-Reply-To: <201002041657.52232.jhb@freebsd.org>
X-Enigmail-Version: 0.96.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 7bit
Cc: freebsd-acpi@freebsd.org
Subject: Re: 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 <freebsd-acpi.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-acpi>,
	<mailto:freebsd-acpi-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-acpi>
List-Post: <mailto:freebsd-acpi@freebsd.org>
List-Help: <mailto:freebsd-acpi-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-acpi>,
	<mailto:freebsd-acpi-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Thu, 04 Feb 2010 22:13:33 -0000

on 04/02/2010 23:57 John Baldwin said the following:
> On Thursday 04 February 2010 2:42:47 pm Andriy Gapon wrote:
>> -	 * TODO: evaluate failure of _OSC.
>> +	 * On some systems evaluation of _OSC/_PDC dynamically
>> +	 * loads the _PSS and other methods.
>>  	 */
> 
> I would only say _OSC here.  I don't think we've seen any systems that load 
> something when _PDC is invoked, only when _OSC is invoked.

Actually, I think that the way it's written should be OK.
I've seen a few DSDTs where both are present and both do the same thing.
E.g.:

    Scope (\_PR.CPU0)
    {
        Name (HI0, Zero)
        Name (HC0, Zero)
        Method (_PDC, 1, NotSerialized)
        {
            Store (CPDC (Arg0), Local0)
            GCAP (Local0)
            Return (Local0)
        }

        Method (_OSC, 4, NotSerialized)
        {
            Store (COSC (Arg0, Arg1, Arg2, Arg3), Local0)
            GCAP (Local0)
            Return (Local0)
        }
...

Looks like CPDC is "Convert _PDC" and COSC is "Convert _OSC" and GCAP is "G...
capabilities", whatever "G..." could mean.

-- 
Andriy Gapon