From owner-freebsd-embedded@FreeBSD.ORG Fri Dec 5 19:09:06 2008 Return-Path: Delivered-To: freebsd-embedded@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 3CF921065677; Fri, 5 Dec 2008 19:09:06 +0000 (UTC) (envelope-from imp@bsdimp.com) Received: from harmony.bsdimp.com (bsdimp.com [199.45.160.85]) by mx1.freebsd.org (Postfix) with ESMTP id F11438FC0A; Fri, 5 Dec 2008 19:09:05 +0000 (UTC) (envelope-from imp@bsdimp.com) Received: from localhost (localhost [127.0.0.1]) by harmony.bsdimp.com (8.14.2/8.14.1) with ESMTP id mB5J80kA015964; Fri, 5 Dec 2008 12:08:00 -0700 (MST) (envelope-from imp@bsdimp.com) Date: Fri, 05 Dec 2008 12:08:06 -0700 (MST) Message-Id: <20081205.120806.1661913579.imp@bsdimp.com> To: stas@freebsd.org From: "M. Warner Losh" In-Reply-To: <20081205113502.f9871231.stas@FreeBSD.org> References: <0FCFCF6165E968449991746EB91D614D01FF35C9@antipi.jnpr.net> <20081205113502.f9871231.stas@FreeBSD.org> X-Mailer: Mew version 5.2 on Emacs 21.3 / Mule 5.0 (SAKAKI) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: freebsd-embedded@freebsd.org Subject: Re: How to support a TrueIDE (ATA) NANDrive chip X-BeenThere: freebsd-embedded@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Dedicated and Embedded Systems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 05 Dec 2008 19:09:06 -0000 In message: <20081205113502.f9871231.stas@FreeBSD.org> Stanislav Sedov writes: : -----BEGIN PGP SIGNED MESSAGE----- : Hash: SHA1 : : On Thu, 4 Dec 2008 17:23:41 -0500 : Andrew Duane mentioned: : : > We have an SST NANDrive chip on our board that supports the simple ATA : > command set. What's the easiest way to get support for this into our : > kernel so we can partition and mount the device? : > : > Using "da" and "umass" isn't really an option, since it is neither SCSI, : > nor attached to USB. Pulling in all of "ata" seems like overkill; all we : > really need is read/write block and some simple sense commands. They are : > all synchronous, it's low traffic and we are more concerned with : > simplicity than performance. Is there some subset of "ata" I can use : > that won't involve pci bus, controllers, etc? We just want to be able to : > write the LBA, SECT_CNT, and GO command and read the data. : > : : Why not attach the ATA stack to the register space the chip provides. : Doesn't look like an overkill to me. It should work pretty well. : I'm using something like this for AT91 CF controller. I'v attached : it source, it might be useful to you. It's simple enough. I'd concur. I believe that we can configure the ata stuff such that we don't get pci, et al, in this case. If not, we should fix that. Warner