From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lin Ming Subject: Re: [PATCH] ACPI: evaluate _PS3 when entering D3 Cold Date: Sun, 01 Apr 2012 14:28:57 +0800 Message-ID: <1333261737.2939.84.camel@minggr> References: <1333217910-29579-1-git-send-email-aaron.lu@amd.com> <1333258053.2939.22.camel@minggr> <20120401055603.GA11505@localhost.amd.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from mga09.intel.com ([134.134.136.24]:49236 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750843Ab2DAG3A (ORCPT ); Sun, 1 Apr 2012 02:29:00 -0400 In-Reply-To: <20120401055603.GA11505@localhost.amd.com> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Aaron Lu Cc: Len Brown , "Rafeal J. Wysocki" , linux-acpi@vger.kernel.org, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, Zhang Rui , Andiry Xu , Alex He On Sun, 2012-04-01 at 13:56 +0800, Aaron Lu wrote: > Hi, >=20 > On Sun, Apr 01, 2012 at 01:27:33PM +0800, Lin Ming wrote: > > > - if (device->power.states[state].flags.explicit_set) { > > > + /* If state is D3 Cold, try to evaluate _PS3 first */ > > > + if (state =3D=3D ACPI_STATE_D3_COLD) { > > > + explicit_set =3D (ps - 1)->flags.explicit_set; > > > + object_name[3] -=3D 1; > > > + } > >=20 > > I'm not sure whether this works or not. > >=20 > > From ACPI spec, > >=20 > > _PS3 "is used to put the specific device into its D3hot or D3 state= " > >=20 > > D3 neither means D3hot nor D3cold. It's an old term before D3hot an= d > > D3cold were introduced. > I guess D3 has to mean something, right? :-) >=20 > Here is the problem, there is no _PR3 in AMD's implementation, just _= PS3. > And since _S0W evaluates 4, I've to put this device into D3 cold stat= e > with _PS3. >=20 > And the ACPI does have some words like: >=20 > ------ > Platform/drivers must assume that the device will have power complete= ly > removed when the device is place into =E2=80=9CD3=E2=80=9D via _PS3 > ------ >=20 > This is in section 7.2.11: _PR3. >=20 > >=20 > > Another problem: > >=20 > > With your patch, both D3hot and D3cold will evaluate _PS3, right? > >=20 > Yes. >=20 > > Will it have problem on AMD platform if you try to put ODD into D3h= ot > > state? _PS3 is evaluated, so it actually enters D3Cold state. >=20 > There is no D3 hot support for this device(from the firmware's > perspective), either it is at D0(via _PS0), or it will be at D3 cold(= via > _PS3). But this is the generic code. We can't only consider some special device. Maybe we need some flag to tell which D3 state _PS3 is used for. Lin Ming >=20 >=20 > Thanks for the review. >=20 > -Aaron >=20 -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html