From owner-freebsd-current@FreeBSD.ORG Thu Jun 1 18:20:00 2006 Return-Path: X-Original-To: current@freebsd.org Delivered-To: freebsd-current@FreeBSD.ORG Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id E88DF16A649 for ; Thu, 1 Jun 2006 18:20:00 +0000 (UTC) (envelope-from imp@bsdimp.com) Received: from harmony.bsdimp.com (vc4-2-0-87.dsl.netrack.net [199.45.160.85]) by mx1.FreeBSD.org (Postfix) with ESMTP id 2CAD843D49 for ; Thu, 1 Jun 2006 18:19:59 +0000 (GMT) (envelope-from imp@bsdimp.com) Received: from localhost (localhost.village.org [IPv6:::1] (may be forged)) by harmony.bsdimp.com (8.13.4/8.13.4) with ESMTP id k51IGWLG077937; Thu, 1 Jun 2006 12:16:33 -0600 (MDT) (envelope-from imp@bsdimp.com) Date: Thu, 01 Jun 2006 12:16:38 -0600 (MDT) Message-Id: <20060601.121638.1273920169.imp@bsdimp.com> To: jb@what-creek.com From: "M. Warner Losh" In-Reply-To: <20060530051455.GA60261@what-creek.com> References: <20060530040220.GA59831@what-creek.com> <9f7850090605292201x570d93b4v8a7dd3ea0c70f841@mail.gmail.com> <20060530051455.GA60261@what-creek.com> X-Mailer: Mew version 4.2 on Emacs 21.3 / Mule 5.0 (SAKAKI) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: atrens@nortel.com, current@freebsd.org, mf.danger@gmail.com, phk@phk.freebsd.dk, Alexander@leidinger.net, small@freebsd.org Subject: Re: FreeBSD's embedded agenda X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 01 Jun 2006 18:20:05 -0000 In message: <20060530051455.GA60261@what-creek.com> John Birrell writes: : As I said, writing a NAND driver under geom on FreeBSD is a trivial matter. : That is what I did. The driver wasn't committed to FreeBSD because it : is hardware specific to the board due to the way the the processor I/O : is mapped. If you study the NAND implementations on embedded hardware, : you will see that making a general operating system support them all with : drivers is hard to do because of the different ways that the NAND chips : are mapped in I/O. It's not like they are on a general bus that makes : access to them the same. Yes. This driver does have a number of issues. There needs to be some additional layers of abstraction to make it generic. The driver you wrote works very well (we only had to fix a one or two minor bugs). Warner