From owner-freebsd-hackers@FreeBSD.ORG Tue Nov 30 14:43:52 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 012AB106575E for ; Tue, 30 Nov 2010 14:43:52 +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 C7CD28FC17 for ; Tue, 30 Nov 2010 14:43:51 +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 7F20F46B06; Tue, 30 Nov 2010 09:43:51 -0500 (EST) Received: from jhbbsd.localnet (smtp.hudson-trading.com [209.249.190.9]) by bigwig.baldwin.cx (Postfix) with ESMTPSA id AC6068A01D; Tue, 30 Nov 2010 09:43:50 -0500 (EST) From: John Baldwin To: freebsd-hackers@freebsd.org Date: Tue, 30 Nov 2010 09:38:52 -0500 User-Agent: KMail/1.13.5 (FreeBSD/7.3-CBSD-20101102; KDE/4.4.5; amd64; ; ) References: <187702.21471.qm@web76808.mail.sg1.yahoo.com> In-Reply-To: <187702.21471.qm@web76808.mail.sg1.yahoo.com> MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201011300938.53006.jhb@freebsd.org> X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.2.6 (bigwig.baldwin.cx); Tue, 30 Nov 2010 09:43:50 -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: Tue, 30 Nov 2010 14:43:52 -0000 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.). -- John Baldwin