From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Renninger Subject: Re: [PATCH] ACPI : RSDT is forced to be used when 32/64X address mismatch in FADT Date: Mon, 21 Apr 2008 12:07:53 +0200 Message-ID: <1208772473.1784.482.camel@queen.suse.de> References: <1208515293.4072.3.camel@yakui_zhao.sh.intel.com> <1208518162.1784.418.camel@queen.suse.de> <1208525704.1784.435.camel@queen.suse.de> <20080419042454.GC11635@khazad-dum.debian.net> Reply-To: trenn@suse.de Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Return-path: Received: from ns2.suse.de ([195.135.220.15]:48704 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754823AbYDUKHz (ORCPT ); Mon, 21 Apr 2008 06:07:55 -0400 In-Reply-To: <20080419042454.GC11635@khazad-dum.debian.net> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Henrique de Moraes Holschuh Cc: Zhao Yakui , lenb@kernel.org, linux-acpi@vger.kernel.org On Sat, 2008-04-19 at 01:24 -0300, Henrique de Moraes Holschuh wrote: > On Fri, 18 Apr 2008, Thomas Renninger wrote: > > I'd take DMI_MATCH(DMI_BIOS_VERSION,"1SET") to match for all. > > Agreed, if 1SET70 has a bug, all other versions of that BIOS before 70 > probably have that bug too. > > > These machines might be very similar (ThinkPad R40e is probably wrong as > > not the name, but the BIOS version which could be the same than for e.g. > > R50 is hit). I expect that C states are going to work if you take the > > -EPARSE. The 1S BIOS *is* the R40e BIOS, and don't understand what you > mean with the R50? The BIOS for the R50, T40, T41 and T42 as well as > some R51 models is the same (BIOS 1R). Sorry, I should have been more detailed... - IIRC the physical HW address to switch to C2/C3 is provided through the FADT table. - For "1SET*" ThinkPad BIOSes, C-states are blacklisted as they freeze if C-states are invoked (see drivers/acpi/processor_idle.c). - This patch chooses an alternate FADT table if the content of the other table differs (either the one pointed to by XSDT or RSDT). - The machine which shows different contents of FADTs is a R50e: http://bugzilla.kernel.org/show_bug.cgi?id=8246 - While the bug was opened because of slow booting (due to wrong HW addresses accessed?), I could imagine Yakui has found the root cause why C-states didn't work on some older ThinkPads. -> It should be tested whether ThinkPads which have C-states blacklisted do work with the other FADT and the blacklist in drivers/acpi/processor_idle.c can be removed or what I meant, it can be moved/reused for a kind of force_rsdt flag... All this is theory and needs testing... I can try to find one of the older ThinkPad models... Thomas