From owner-freebsd-net@FreeBSD.ORG Mon Nov 7 16:18:59 2005 Return-Path: X-Original-To: freebsd-net@freebsd.org Delivered-To: freebsd-net@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id B882916A420; Mon, 7 Nov 2005 16:18:59 +0000 (GMT) (envelope-from jhb@freebsd.org) Received: from speedfactory.net (mail5.speedfactory.net [66.23.216.218]) by mx1.FreeBSD.org (Postfix) with ESMTP id CAA5A43D86; Mon, 7 Nov 2005 16:18:42 +0000 (GMT) (envelope-from jhb@freebsd.org) Received: from server.baldwin.cx (unverified [66.23.211.162]) by speedfactory.net (SurgeMail 3.5b3) with ESMTP id 1523317 for multiple; Mon, 07 Nov 2005 11:20:40 -0500 Received: from localhost.baldwin.cx (john@localhost [127.0.0.1]) by server.baldwin.cx (8.13.1/8.13.1) with ESMTP id jA7GIXrN011431; Mon, 7 Nov 2005 11:18:33 -0500 (EST) (envelope-from jhb@freebsd.org) From: John Baldwin To: freebsd-acpi@freebsd.org Date: Mon, 7 Nov 2005 11:05:56 -0500 User-Agent: KMail/1.8.2 References: <20051027233636.GA39380@dmw.hopto.org> <436E874E.4010305@root.org> In-Reply-To: <436E874E.4010305@root.org> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200511071105.58729.jhb@freebsd.org> X-Spam-Status: No, score=-2.8 required=4.2 tests=ALL_TRUSTED autolearn=failed version=3.0.2 X-Spam-Checker-Version: SpamAssassin 3.0.2 (2004-11-16) on server.baldwin.cx X-Server: High Performance Mail Server - http://surgemail.com r=100 Cc: freebsd-net@freebsd.org, Vaibhave Agarwal , current@freebsd.org, chris@gnome.co.uk, Nate Lawson Subject: Re: Freebsd 6.0 doesnt detect local APIC on a Pentium 3 machine X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 07 Nov 2005 16:18:59 -0000 On Sunday 06 November 2005 05:44 pm, Nate Lawson wrote: > Vaibhave Agarwal wrote: > > On Sun, 6 Nov 2005, John Baldwin wrote: > >>We don't detect the local APIC via MSR's or the APIC bit in cpu_features, > >> but rely on a working MP Table or MADT table to setup both the local > >> APIC(s) and I/O APIC(s). Does your machine have a valid MP Table or an > >> APIC table in its acpidump? Many UP machine BIOSes don't include those > >> tables. > > > > I think you are right. > > There is no valid APIC table in the acpidump. > > The only place where APIC is mentioned in the acpidump(8) is in > > following: > > > > Scope (\_SB) > > { > > Name (APIC, 0x00) > > Method (_PIC, 1, NotSerialized) > > { > > Store (Arg0, APIC) > > } > > } > > > > > > And I suppose APIC is disabled in the BIOS too. > > Is there a way to enable APIC using software, without changing the BIOS, > > since I dont have access to the BIOS, as it is a remote machine (with > > root access) ? > > The above references to APIC just store a value in a convenience > variable. If there's nothing else in the AML that references the > \_SB.APIC variable, then it has no effect on the system. In that case, > the only way to get APIC support on that machine is to implement another > way of enumerating it. And even then it can't be used for any device interrupts since there aren't any I/O APICs. On a UP machine without I/O APICs, it's actually probably more optimal to just use irq0 and irq8 for clocks rather than the lapic timer anyway. The only real possible gain is the ability to use the profiling interrupt from the local APIC. -- John Baldwin <>< http://www.FreeBSD.org/~jhb/ "Power Users Use the Power to Serve" = http://www.FreeBSD.org