From owner-freebsd-mobile Fri Mar 12 18:34:18 1999 Delivered-To: freebsd-mobile@freebsd.org Received: from netrinsics.com (unknown [210.74.174.104]) by hub.freebsd.org (Postfix) with ESMTP id 504C014DB3 for ; Fri, 12 Mar 1999 18:34:12 -0800 (PST) (envelope-from robinson@netrinsics.com) Received: (from robinson@localhost) by netrinsics.com (8.9.2/8.8.7) id KAA35091 for freebsd-mobile@freebsd.org; Sat, 13 Mar 1999 10:03:44 +0800 (CST) (envelope-from robinson) Date: Sat, 13 Mar 1999 10:03:44 +0800 (CST) From: Michael Robinson Message-Id: <199903130203.KAA35091@netrinsics.com> To: freebsd-mobile@freebsd.org Subject: Re: compatibility list In-Reply-To: <19990313025010.C64180@clear.co.nz> Sender: owner-freebsd-mobile@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org Joe Abley writes: >Is the idea to treat _all_ busses as potentially supporting nomadic devices, >to give maximum genericism? Is there _any_ device that needs to be treated >as permenant? > >If _all_ devices are generically considered removable, does this make a >devfs-type scheme more workable? Or were the previous issues with devfs >different? I see two related issues: First, the controllers that manage removable devices may themselves be removable, or otherwise controlled by controllers with such management features. Consider the pathological case of a docking station with a PCI card slot filled with a PCMCIA controller which has USB PC-CARD connected to a USB SCSI adapter. Any removeable device abstraction has to recurse elegantly. Which brings up the second point, which is how to handle bootstrapping under this abstraction. I haven't had a chance to look at the new three-stage boot, but I wonder whether it can boot a kernel image from a PC-CARD ATA device. I guess my question is, where exactly does one draw the line about "no probing during boot". Are BIOS devices forever and always a special case? What about ROM-assisted "net-boot" and the like? -Michael Robinson To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-mobile" in the body of the message