From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew de Quincey Subject: Re: Possible quick fix for ACPI routing problem on Nforce2 Date: Sun, 13 Jul 2003 02:18:44 +0100 Sender: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Message-ID: <200307130218.44398.adq_dvb@lidskialf.net> References: <200307122352.45704.adq_dvb@lidskialf.net> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <200307122352.45704.adq_dvb-fmPXVN3awWJAJAzL26g0SA@public.gmane.org> Content-Disposition: inline Errors-To: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Help: List-Post: List-Subscribe: , List-Unsubscribe: , List-Archive: To: acpi-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: linux-acpi@vger.kernel.org Hi, I've been playing about with this, and I've found what is happening. I've not yet tracked down the reason yet, but if anyone else has this problem, can they try please this fix to see if it is consistent. Anyway, IRQs > 15 get set to Active low/Level Sensitive in the IO-APIC on my board. The fix (No patch as this is NOT a proper fix): Edit arch/i386/kernel/io_apic.c Find the function io_apic_set_pci_routing() (its the last one in 2.5.74). Change the line: entry.polarity = 1; /* Low active */ To: entry.polarity = 0; /* High active */ For me, this makes everything work fine. Originally, I also forced these IRQs to be edge sensitive, but leaving them at level seems to work fine as well. Now, I assume one of the other functions in io_apic.c is _meant_ to be called to set this correctly. My next step is to track down why this is not occurring. A question: Why are these set to level/activelow in a function which is labelled to be setting up PCI IRQs? I'd assumed they were always edge/active high.. or is this not necessarily the case? ------------------------------------------------------- This SF.Net email sponsored by: Parasoft Error proof Web apps, automate testing & more. Download & eval WebKing and get a free book. www.parasoft.com/bulletproofapps1