From owner-freebsd-hackers@FreeBSD.ORG Thu Dec 2 14:05:29 2010 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id A45091065670 for ; Thu, 2 Dec 2010 14:05:29 +0000 (UTC) (envelope-from jhb@freebsd.org) Received: from cyrus.watson.org (cyrus.watson.org [65.122.17.42]) by mx1.freebsd.org (Postfix) with ESMTP id 77E118FC08 for ; Thu, 2 Dec 2010 14:05:29 +0000 (UTC) Received: from bigwig.baldwin.cx (66.111.2.69.static.nyinternet.net [66.111.2.69]) by cyrus.watson.org (Postfix) with ESMTPSA id 3251046B35; Thu, 2 Dec 2010 09:05:29 -0500 (EST) Received: from jhbbsd.localnet (smtp.hudson-trading.com [209.249.190.9]) by bigwig.baldwin.cx (Postfix) with ESMTPSA id 085BF8A01D; Thu, 2 Dec 2010 09:05:28 -0500 (EST) From: John Baldwin To: freebsd-hackers@freebsd.org Date: Thu, 2 Dec 2010 08:58:13 -0500 User-Agent: KMail/1.13.5 (FreeBSD/7.3-CBSD-20101102; KDE/4.4.5; amd64; ; ) References: <948728.57388.qm@web76807.mail.sg1.yahoo.com> In-Reply-To: <948728.57388.qm@web76807.mail.sg1.yahoo.com> MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-15" Content-Transfer-Encoding: 7bit Message-Id: <201012020858.13914.jhb@freebsd.org> X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.2.6 (bigwig.baldwin.cx); Thu, 02 Dec 2010 09:05:28 -0500 (EST) X-Virus-Scanned: clamav-milter 0.96.3 at bigwig.baldwin.cx X-Virus-Status: Clean X-Spam-Status: No, score=-1.9 required=4.2 tests=BAYES_00 autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on bigwig.baldwin.cx Cc: Darmawan Salihun Subject: Re: How to debug BTX loader? X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 02 Dec 2010 14:05:29 -0000 On Wednesday, December 01, 2010 4:09:42 pm Darmawan Salihun wrote: > Hi John, > > --- On Tue, 11/30/10, John Baldwin wrote: > > > From: John Baldwin > > Subject: Re: How to debug BTX loader? > > To: freebsd-hackers@freebsd.org > > Cc: "Darmawan Salihun" > > Date: Tuesday, November 30, 2010, 9:38 AM > > On Monday, November 29, 2010 1:01:27 > > pm Darmawan Salihun wrote: > > > Hi guys, > > > > > > I'm currently working on a BIOS for a custom Single > > Board Computer (SBC). > > > I have the required BIOS source code and tools at > > hand. > > > However, the boot process always stuck in the BTX > > loader > > > (the infamous "ACPI autoload failed") when I booted > > out of USB stick > > > (with the FreeBSD 8.1 USB stick image). > > > > > > I could get the system to boot into FreeBSD 8.1 > > > (by keeping the CDROM tray open and close it when the > > board looks for > > > boot device, otherwise BTX will reboot instantly). > > > > Are you getting an actual BTX error message or a > > freeze? BTX is just a > > minikernel written all in assembly. It doesn't handle > > loading the kernel, > > etc. All that work is done by the /boot/loader > > program (which is written in > > C). You can find all the source to the boot code in > > src/sys/boot. The BTX > > kernel is in src/sys/boot/i386/btx/btx/. > > > > However, to debug this further we would need more info such > > as what exactly > > you are seeing (a hang, a BTX fault with a register dump, > > etc.). > > One of the BTX fault shows the register dump in the attachment. > I hope this could help. Anyway, If I were to try to interpret > such register dump, where should I start? I understand x86/x86_64 > assembly pretty much, but I'm not quite well versed with the > FreeBSD code using it. Looks like the mailing list stripped the attachment. Can you post the attachment at a URL? -- John Baldwin