From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Renninger Subject: Re: _CST implementation Date: Mon, 18 Apr 2005 19:25:54 +0200 Message-ID: <4263EDA2.4030106@suse.de> References: <1113598244.8367.30.camel@scotchmobil> <20050418120744.GG2298@poupinou.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20050418120744.GG2298-kk6yZipjEM5g9hUCZPvPmw@public.gmane.org> Sender: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Errors-To: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , List-Archive: To: Bruno Ducrot Cc: Janosch Machowinski , acpi-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: linux-acpi@vger.kernel.org Bruno Ducrot wrote: > On Fri, Apr 15, 2005 at 10:50:44PM +0200, Janosch Machowinski wrote: ... > >>Oh I almost forgot another question : >>About the validation of the C states. At the moment it is tested if the >>latency of C2 if under 100 and if C3 latency is under 1000 but the >>ACPI-Spec says that "There is no latency restrictions" so why do you do >>this ? (My notebook hat a C3 latency of 1001) > > Normally you are right, but unfortunately there are still some strange > misread of the specification by bios writters in that regard. Therefore > if for C3 the latency is 1001 even if given by _CST, we should disable > it. > My spec says (Revision 3.0, September 2, 2004): The worst-case hardware latency for this state is declared in the FADT (p. 257). And there they say (p. 98): The worst-case hardware latency, in microseconds, to enter and exit a C2 state. A value > 100 indicates the system does not support a C2 state. The worst-case hardware latency, in microseconds, to enter and exit a C3 state. A value > 1000 indicates the system does not support a C3 state. Thomas ------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click