From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Fri, 10 Aug 2001 12:47:29 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Fri, 10 Aug 2001 12:47:19 -0400 Received: from quattro.sventech.com ([205.252.248.110]:12046 "HELO quattro.sventech.com") by vger.kernel.org with SMTP id ; Fri, 10 Aug 2001 12:47:03 -0400 Date: Fri, 10 Aug 2001 12:47:15 -0400 From: Johannes Erdfelt To: "Eric W. Biederman" Cc: Mike Jadon , linux-kernel@vger.kernel.org Subject: Re: PCI NVRAM Memory Card Message-ID: <20010810124715.F1575@sventech.com> In-Reply-To: <5.1.0.14.0.20010622101907.03ac21b0@192.168.0.5> <20010810114011.X3126@sventech.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.3.12i In-Reply-To: ; from ebiederm@xmission.com on Fri, Aug 10, 2001 at 10:31:08AM -0600 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Aug 10, 2001, Eric W. Biederman wrote: > Johannes Erdfelt writes: > > > On Fri, Aug 10, 2001, Eric W. Biederman wrote: > > > Mike Jadon writes: > > > > > > > My company has released a PCI NVRAM memory card but we haven't developed a > > Linux > > > > > > > > > > driver for it yet. We want the driver to be open to developers to build > > upon. > > > > > > Is there a specific path we should follow with this being our goal? > > > > > > You might want to check out the development of the mtd subsystem. > > > http://www.linux-mtd.infradead.org/ > > > > > > This is probably what you want to write a driver for for your NVRAM PCI card. > > > > Not really. > > > > In their case, it's a bunch of standard SDRAM on a PCI card with a > > battery backup. It's not flash. > > > > A block device is all that's needed. > > O.k. that make sense, NVRAM has so many meanings... It still might > make sense to support things like JFFS, and friends, though. So the > reference isn't totally wasted. As a block device, anything is available to be used :) > Somehow I missed the reference to a description of what kind of > hardware is being discussed. I wonder if the card can do DMA. > Without bus mastering it looks tricky to get burts over the PCI bus, > which would intern mean the card would be relatively slow. And for > things like keeping a journal for your filesystem generally the faster > the better. Being able to get 128MB/s would be pretty cool. It can do DMA, even scatter gather. It's 64 bit too. It's pretty nice. JE