Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752874AbWLQP6x (ORCPT ); Sun, 17 Dec 2006 10:58:53 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752875AbWLQP6x (ORCPT ); Sun, 17 Dec 2006 10:58:53 -0500 Received: from yumi.tdiedrich.de ([85.10.210.183]:3215 "EHLO yumi.tdiedrich.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752873AbWLQP6w (ORCPT ); Sun, 17 Dec 2006 10:58:52 -0500 Date: Sun, 17 Dec 2006 16:58:50 +0100 From: Tobias Diedrich To: "Pallipadi, Venkatesh" Cc: Len Brown , Ingo Molnar , Andreas Mohr , Thomas Gleixner , linux-kernel@vger.kernel.org, "Van De Ven, Arjan" Subject: Re: CONFIG_NO_HZ: missed ticks, stall (keyb IRQ required) [2.6.18-rc4-mm1] Message-ID: <20061217155850.GA2765@melchior.yamamaya.is-a-geek.org> Mail-Followup-To: Tobias Diedrich , "Pallipadi, Venkatesh" , Len Brown , Ingo Molnar , Andreas Mohr , Thomas Gleixner , linux-kernel@vger.kernel.org, "Van De Ven, Arjan" References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.13 (2006-08-11) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2515 Lines: 61 Pallipadi, Venkatesh wrote: > There are two things that can be happening when OS does not see HPET in > ACPI. > - BIOS did enable HPET in chipset and did not communicate it to OS. > - BIOS did nothing to enable HPET in chipset. > > The quirk below tries to find the HPET base address in case 1. But in > case 2 this will also fail as HPTC will be 0 below (Probably we can > still assume default base address of 0xFED00000 and probe there. But I > am still checking on that). I just added couple of chipset ids that I > could test on... > > On the systems that I tested, HPTC was zero (case 2 above) and patch > below did not really help. > > I am building on this patch to enable HPET in late init stage based on > the the quirk information. Will be interesting to see what this patch > says on other ICH based systems that don't have HPET info in ACPI. In case anyone is interested, here is some information about the HPET on nVidia MCP55: With the recent update to BIOS Version 0609, ASUS has added HPET Support and a Enable/Disable BIOS option for the M2N SLI Deluxe. 00:01.0 0601: 10de:0360 (rev a2) 00:01.0 ISA bridge: nVidia Corporation MCP55 LPC Bridge (rev a2) 00: de 10 60 03 0f 00 a0 00 a2 00 01 06 00 00 80 00 10: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 20: 00 00 00 00 00 00 00 00 00 00 00 00 43 10 39 82 30: 00 00 00 00 00 00 00 00 00 00 00 00 ff 00 00 00 40: 43 10 39 82 00 f0 ff fe fa 3e ff 00 fa 3e ff 00 ^^^^^^^^^^^ HPET base address [ 0.000000] ACPI: HPET id: 0x10de8201 base: 0xfefff000 50: fa 3e ff 00 00 5a 62 02 00 00 00 01 00 00 ff ff 60: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 f9 ff 70: 10 00 ff ff c5 80 00 00 00 00 44 19 40 06 00 03 ^^ c1 => HPET disabled c5 => HPET enabled 80: 09 10 00 00 82 0d 00 00 c0 00 00 01 f0 00 00 00 90: 80 08 00 00 00 00 00 00 21 47 95 86 ef cd ab 00 a0: 01 00 30 c0 00 00 00 00 00 00 00 00 00 00 00 00 b0: 90 02 ef 02 00 08 5f 08 00 00 00 00 00 00 00 00 c0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 d0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 e0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 f0: 00 00 00 00 00 00 00 00 10 00 00 00 00 00 00 00 HTH, -- Tobias PGP: http://9ac7e0bc.uguu.de - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/