From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S265069AbTFYVAP (ORCPT ); Wed, 25 Jun 2003 17:00:15 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S265080AbTFYVAP (ORCPT ); Wed, 25 Jun 2003 17:00:15 -0400 Received: from e35.co.us.ibm.com ([32.97.110.133]:63742 "EHLO e35.co.us.ibm.com") by vger.kernel.org with ESMTP id S265069AbTFYVAJ (ORCPT ); Wed, 25 Jun 2003 17:00:09 -0400 Subject: [PATCH] linux_2.4.22-pre2_clear-smi-fix_A0 From: john stultz To: marcelo Cc: Alan Cox , lkml Content-Type: text/plain Organization: Message-Id: <1056575114.27508.13.camel@w-jstultz2.beaverton.ibm.com> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.2.4 Date: 25 Jun 2003 14:05:14 -0700 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Marcelo, all, This is a backported fix from 2.5. Some of our more recent hardware requires that SMIs are routed through the IOAPIC, thus when we clear_IO_APIC() at boot time, we clear the BIOS initialized SMI pin. This basically clobbers the SMI so we can then never make the transition into ACPI mode. Additionally various other SMI functions cease to work. This patch simply reads the apic entry in clear_IO_APIC to make sure the delivery_mode isn't dest_SMI. If it is, we leave the apic entry alone and return. With this patch, the box boots and SMIs function properly. Please consider for inclusion. thanks -john diff -Nru a/arch/i386/kernel/io_apic.c b/arch/i386/kernel/io_apic.c --- a/arch/i386/kernel/io_apic.c Wed Jun 25 13:27:07 2003 +++ b/arch/i386/kernel/io_apic.c Wed Jun 25 13:27:07 2003 @@ -169,6 +169,14 @@ { struct IO_APIC_route_entry entry; unsigned long flags; + + /* Check delivery_mode to be sure we're not clearing an SMI pin */ + spin_lock_irqsave(&ioapic_lock, flags); + *(((int*)&entry) + 0) = io_apic_read(apic, 0x10 + 2 * pin); + *(((int*)&entry) + 1) = io_apic_read(apic, 0x11 + 2 * pin); + spin_unlock_irqrestore(&ioapic_lock, flags); + if (entry.delivery_mode == dest_SMI) + return; /* * Disable it in the IO-APIC irq-routing table: