From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932250AbWE3OF5 (ORCPT ); Tue, 30 May 2006 10:05:57 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932273AbWE3OF4 (ORCPT ); Tue, 30 May 2006 10:05:56 -0400 Received: from nz-out-0102.google.com ([64.233.162.197]:52567 "EHLO nz-out-0102.google.com") by vger.kernel.org with ESMTP id S932250AbWE3OF4 (ORCPT ); Tue, 30 May 2006 10:05:56 -0400 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=beta; d=gmail.com; h=received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=a0T4EA95So8rrQADpSDKGgwzJsDpyZ45uTElfYzS1TILMYNkBUoEkSQWbPgfkF+ACIPUC2fSOGkEyNQRnuzjBKAcQ2p0TJ92iqUaGTPHShCBjRoYzmDuWzeg1tIs22gsHfoFw8eXvU6whTQXvv3qhrbz5X2f8t9xUCxlc4+M16A= Message-ID: <20f65d530605300705l60bfcca7k47a41c95bf42a0ef@mail.gmail.com> Date: Wed, 31 May 2006 02:05:44 +1200 From: "Keith Chew" To: "Erik Mouw" Subject: Re: IO APIC IRQ assignment Cc: linux-kernel@vger.kernel.org In-Reply-To: <20060530135017.GD5151@harddisk-recovery.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <20f65d530605300521q1d56c3a3t84be3d92f1df0c14@mail.gmail.com> <20060530135017.GD5151@harddisk-recovery.com> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hi Erik > That sounds like a nice MythTV box to me :) > Yes it is! We are using the box as a video surveillance unit for the automotive industry (eg trains, buses). We are using the USB for WIFI, which is causing pain with the bttv drivers in IRQ sharing mode. Increasing the PCI latency of the bttv allow it to not give up the IRQ that often to the WIFI. The bttv FAQ did mention that the drivers works "most of the time" in IRQ sharing, I guess we are seeing the random freezes because our application is 24x7. > > Or the engineer means that in legacy PIC mode the IRQs are shared, but > in APIC mode they can be separated. That is a different thing, cause in > that case the IRQ lines are not physically connected, but put together > in PIC mode and can again be separated by using APIC mode. > Ah, you could be right here. In the BIOS, there an option to enable/disable APIC, which corresponds to what you are suggesting above. Unfortunately, we have tried all the options we know to separate the IRQs in IO APIC mode, but to no avail. Next, we will be testing the unit in Windows to verify the engineer's claims. Thanks again for taking the time to respond to my post. Regards Keith