From owner-cvs-src@FreeBSD.ORG Wed Feb 1 13:43:29 2006 Return-Path: X-Original-To: cvs-src@freebsd.org Delivered-To: cvs-src@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 7444816A420; Wed, 1 Feb 2006 13:43:29 +0000 (GMT) (envelope-from martin@gneto.com) Received: from av9-2-sn2.hy.skanova.net (av9-2-sn2.hy.skanova.net [81.228.8.180]) by mx1.FreeBSD.org (Postfix) with ESMTP id C8B7143D46; Wed, 1 Feb 2006 13:43:28 +0000 (GMT) (envelope-from martin@gneto.com) Received: by av9-2-sn2.hy.skanova.net (Postfix, from userid 502) id E466F3818B; Wed, 1 Feb 2006 14:43:26 +0100 (CET) Received: from smtp4-2-sn2.hy.skanova.net (smtp4-2-sn2.hy.skanova.net [81.228.8.93]) by av9-2-sn2.hy.skanova.net (Postfix) with ESMTP id BFF3A37FC7; Wed, 1 Feb 2006 14:43:26 +0100 (CET) Received: from [192.168.2.30] (h99n2fls34o985.telia.com [213.66.202.99]) by smtp4-2-sn2.hy.skanova.net (Postfix) with ESMTP id 5075337E4D; Wed, 1 Feb 2006 14:43:25 +0100 (CET) Message-ID: <43E0BAF6.4080501@gneto.com> Date: Wed, 01 Feb 2006 14:43:18 +0100 From: Martin Nilsson User-Agent: Thunderbird 1.5 (Windows/20051201) MIME-Version: 1.0 To: babkin@users.sf.net References: <3362285.1138799355022.JavaMail.root@vms170.mailsrvcs.net> In-Reply-To: <3362285.1138799355022.JavaMail.root@vms170.mailsrvcs.net> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Peter Jeremy , src-committers@freebsd.org, cvs-all@freebsd.org, cvs-src@freebsd.org, Scott Long Subject: Re: cvs commit: src/release Makefile X-BeenThere: cvs-src@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: CVS commit messages for the src tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 01 Feb 2006 13:43:29 -0000 Sergey Babkin skrev: >> From: Peter Jeremy > >> Some time ago, I was surprised to find that my son's oldish (mid 2003) >> system was happy to try and boot off a USB memory stick. > > The BIOSes have been able to do this feat for a while now. There are two caveats though: > > 1. It's slow, since BIOSes tend to use USB 1.x speeds, > and even that not in a really fast way. So the big > images are best to be avoided. Though probably it's > still faster than floppies. > > 2. Accessing the root filesystem - the USB drivers > have to be either statically compiled into the > kernel or be loaded by the boot loader through BIOS > (maybe through an analog of initrd ram disk - I'm > not sure what advances have been done to the FreeBSD > boot loader nowadays). There is another major caveat for some BIOSes: 3. The BTX loader is a 32-bit program that calls the BIOS functions via v86 calls, these calls fails on some BIOSes when a disk/cd is attached with USB resulting in the infamous BTX halted error. I've been told that this is due to the fact that the BIOS tries to enter 32-bit mode again not realizing that the CPU already is in this mode. I recently found out that there is something called BIOS32, a 32-bit interface to the BIOS functions. More info here: http://www.mega-tokyo.com/osfaq2/index.php/I%20heard%20you%20can%20do%20PCI%20calls%20with%20the%20BIOS%20in%20Protected%20Mode%3F I haven't had time to see if calling the function that blows up when booting from USB-CD (check which drives are available) thru BIOS32 is going to work or not. I have lots of boards that have this problem (Supermicro P8SCi for one), if someone wants to have any changes tested. I thought using a USB thumb drive instead of a CD-RW would be easier but I haven't had time to do anything with yet. /Martin